Practical Plastic Surgery - part 8 ppsx

It is worth mentioning that the IP joint of the thumb is extended by thecombined actions of all three major nerves: the radial nerve EPL, the median nervethenar muscles and the ulnar ner

465Anatomy of the Hand

The tendon of FDS inserts on the volar aspect of the middle phalanx, and theFDP tendon inserts on the volar aspect of the distal phalanx FDS flexes the PIPjoint and FDP flexes primarily the DIP joint In the digits, the flexor tendons travel

in synovial-lined tunnels called flexor tendon sheaths The sheaths are anchored tothe bones by a series of five annular pulleys, numbered A1-A5 from proximal todistal The odd numbered pulleys are located over the joints; the even pulleys lieover the bones There are three thin cruciate pulleys, numbered C1-C3, that main-tain tendon motion and collapse during flexion The palmer aponeurosis lies proxi-mal to the A1 pulley and is often referred to as the A0 pulley It acts in unison withthe first two annular pulleys Proximal to the entrance into the digital sheath (A1pulley), the FDS tendon lies palmer to the FDP tendon At this point, the FDStendon divides and becomes deep to the FDP tendon The two portions reunite atCamper’s chiasma and go on to attach to the middle phalanx The FDP tendon,after passing through the FDS bifurcation, attaches to the distal phalanx

Flexor pollicis longus (FPL) is the primary flexor of the thumb It is the most radialstructure in the carpal tunnel It travels in its own fibrous sheath in the palm and insertsinto the base of the distal phalanx of the thumb The thumb, unlike the fingers, has twoannular pulleys, A1 and A2, located over the MP and IP joints, respectively Lyingbetween them is an oblique pulley that is the most important of these three pulleys

Fingertip

The fingertip is the end organ for touch, enabling the hand to relay the shape, perature, and texture of an object The skin covering the pulp of the finger is very durableand has a thick epidermis with deep papillary ridges The glabrous skin of the fingertip iswell-suited for pinch and grasp functions Its volar surface consists of a fatty pulp covered

tem-by highly innervated skin The skin of the fingertip is firmly anchored to the underlyingterminal phalanx by multiple fibrous septa that traverse the fatty pulp Hence an infec-tion that develops within the pulp can result in a closed space infection, or felon

Dorsal Anatomy

Wrist

The extrinsic muscles that extend the hand and fingers enter the wrist throughsix synovial-lined, dorsal compartments covered by the extensor retinaculum At thewrist, the tendons are surrounded by a sheath, but this sheath is not present in thehand and fingers The six compartments are numbered 1-6 from radial to ulnar:

1 Abductor pollicis longus (APL), extensor pollicis brevis (EPB)

2 Extensor carpi radialis brevis (ECRB), extensor carpi radialis longus (ECRL)

3 Extensor pollicis longus (EPL)

4 Extensor digitorum communis (EDC), extensor indices proprius (EIP)

5 Extensor digiti minimi (EDM)

6 Extensor carpi ulnaris (ECU)

The first compartment is commonly involved in stenosing tenosynovitis, termed

de Quervain’s disease The second compartment contains the radial extensors of thewrist, and this compartment is located beneath the anatomic snuffbox The hollow

of the snuffbox (so named because it was a common site for the placement of snuff )

is easily created by extending and abducting the thumb The radial artery passesthrough the snuffbox, and the scaphoid bone is deep to it Therefore, tenderness inthe snuffbox can be seen in scaphoid fractures The second and third compartmentsare separated by Lister’s tubercle

Hand and Fingers

The four fingers are extended by EDC; however the communis tendon to thelittle finger is present only 50% of the time The index and little fingers also haveindependent extensor muscles—EIP and EDM, respectively These tendons usuallylie ulnar and deep to the communis tendons to these two fingers

The EDC tendons are joined proximally to the MP joints by the juncturaetendinum They are almost always present between the EDC of the middle, ringand little fingers Thus, lacerations proximal to the juncturae may not impair digitextension due to the connection to the adjacent digits The tendons inserts proxi-mally into the MP joint volar plate through attachments known as the sagittal bands.Distal to the MP joint, the extensor tendons divide into one central and two lateralslips The central slip inserts into the middle phalanx and extends the PIP joint Thelateral slips reunite distally and attach to the distal phalanx, extending the DIP joint.The thumb is extended by three tendons: the first metacarpal by APL, the proxi-mal phalanx by EPB, and the distal phalanx by EPL However, the MP and IP joints

of the thumb can both be extended by EPL due to the attachments of the dorsalapparatus It is worth mentioning that the IP joint of the thumb is extended by thecombined actions of all three major nerves: the radial nerve (EPL), the median nerve(thenar muscles) and the ulnar nerve (adductor pollicis)

Deep to the extensor tendons and proximal to the metacarpals lies the dorsalcarpal arch This is the dorsal anastomosis between the radial and ulnar circulation.The dorsal metacarpal arteries originate from this arch

Fingertip

The fingernail protects the fingertip and has a major role in tactile sensation andfine motor skills The nail complex, or perionychium, includes the nail plate, the nailbed, and the surrounding skin on the dorsum of the fingertip (paronychium) Thefingernail is a plate of flattened cells layered together and adherent to one another.The nail bed lies immediately deep to the fingernail The nail bed is composed of thegerminal matrix, the sterile matrix, and the roof of the nail fold The germinal matrix,which produces over 90% of nail volume, extends from the proximal nail fold to thedistal end of the lunula The lunula represents the transition zone of the proximalgerminal matrix and distal sterile matrix of the nail bed The sterile matrix (ventralnail) contributes additional substance largely responsible for nail adherence The roof

of the nail fold (dorsal nail), which includes the germinal matrix, is responsible forthe smooth, shiny surface of the nail plate The hyponychium is the area immediatelybelow the fingernail at its cut edge which serves as a barrier to subungual infection,and also marks the terminal extension of bone support for the nail bed The epony-chium is the skin covering the dorsal roof of the nail fold The paronychium is theskin at the nail margin, folded over its medial and lateral edges

Innervation of the Hand and Fingers

The median, ulnar and radial nerves are the primary nerves of the hand and fingers.The first two have both motor and sensory fibers, whereas the radial nerve providesonly sensory fibers to the hand Its motor branches terminate in the arm and forearm

467Anatomy of the Hand

thenar region At the wrist it enters the carpal tunnel, where it is the most superficial

of the structures that traverse this tunnel as described above It then gives off themotor branch which innervates the radial side of the thenar muscles: opponenspollicis, abductor pollicis brevis, the superficial part of flexor pollicis brevis, as well

as the two radial lumbricals Finally, it divides into sensory branches whose territoryincludes the palmar surface of the thumb, index, middle, and radial side of the ringfingers, and the radial side of the palm (palmar sensory branch) On the dorsalsurface, it sends sensory branches to the distal third of the above-mentioned fingers.The most consistent sign of median nerve injury is loss of skin sensibility on thepalmer surface of the first three digits and loss of thenar opponens function

Ulnar Nerve

The ulnar nerve travels in the forearm ulnar to the FDP muscle belly It gives offits palmar sensory branch proximal to the wrist At the wrist it travels in Guyon’scanal, after which it begins to branch into many motor and sensory branches Itinnervates all the intrinsic hand muscles except those mentioned above that areinnervated by the median nerve The last muscle innervated by the ulnar nerve is thefirst dorsal interosseus nerve Its sensory territory includes both the palmar anddorsal sides of the little finger and the ulnar side of the ring finger

A common sensory sign of ulnar nerve injury is the loss of sensibility to the smalland ulnar side of the ring fingers Motor signs include FCU paralysis, interosseous andthumb adduction loss with a weak “key pinch,” and FDP paralysis of the small andring fingers A long-standing injury can present with the classic “claw hand” deformity

Radial Nerve

The radial nerve provides all the motor innervation of the extensor muscles ofthe forearm Only the superficial branch of the radial nerve reaches the hand Thispurely sensory nerve travels over the radial side of the wrist It then branches intothe dorsal digital nerves that supply the skin on the dorsum of the thumb, index,middle, and radial side the ring fingers (with the exception of the distal third of eachwhich is supplied by the median nerve)

Signs of injury include loss of sensibility on the dorsum of the hand and in thefirst web space Patients will be unable to extend their fingers

Pearls and Pitfalls

A resource that is highly recommended for understanding hand anatomy and

anatomic relationships is The Interactive Hand CD-ROM (McGrouther DA, Colditz

JC, Harris JM, Eds.) published by Primal Pictures, Inc 2002 The upper extremitycan be rotated and displayed from various angles, and it can be viewed layer by layerfrom bone to skin

Figure 78.1 P-A view

of a normal hand graph

469Radiographic Findings

A Systematic Approach

An organized evaluation is required for all image interpretation The patient’sname, date of exam, correct body part, and laterality (right or left side) should beverified prior to analyzing the image The exam should be assessed for quality andcompleteness Attention can then be turned to film interpretation The bones, jointspaces, and soft tissues should be sequentially inspected Each feature should beevaluated in a systematic fashion (e.g., from proximal to distal) All abnormalitiesshould be confirmed on a second view

Figure 78.2 Oblique view of a normal hand radiograph

Figure 78.3 Osteoarthritis of thehand, with joint space narrowingand adjacent bony sclerosis TheDIP joints and 1st CMC joint(thumb) are characteristically in-volved

Figure 78.4 Osteoarthritis of thefingers Note greater involvement

of the DIP joints compared to the

IP joints

Figure 78.5 Fracture of thescaphoid bone The scaphoid isthe most commonly fractured car-pal bone, accounting for 80% ofall carpal fractures It is often theresult of a fall on an outstretchedhand Scaphoid fractures are athigh risk for nonunion and avas-cular necrosis

471Radiographic Findings

Figure 78.6 Fracture of the dial styloid, also termed achauffeur’s fracture A scapho-lunate ligament tear often ac-companies this fracture

ra-Figure 78.7 Fracture of thefirst metacarpal base, If it isintra-articular, it is referred to

as a Bennett fracture If it alsodemonstrates comminution, it

is called a Rolando fracture

Figure 78.8 Fifth metacarpal fracture,

commonly known as a boxer’s fracture

Figure 78.9 Fracture of the hamatebone Hook fractures commonly occur

in golfers, baseball players or tion workers with a complaint of a dullache when gripping

construc-Figure 78.10 Fracture of the distal phalanx, or a malletfracture Distal phalanx fractures can occur due to avul-sion of a bony fragment attached to the flexor or exten-sor tendon

473Radiographic Findings

Figure 78.11 Dislocation of the lunate bone in the P-A (A) and lateral views (B).Note the normal position of the capitate bone with respect to the distal radius Inmilder cases, the lunate can sublux dorsally after scapholunate ligament disruption(DISI) and will rarely sublux volarly after lunotriquetral ligament disruption (VISI)

Figure 78.12 Triquetrum fracture ally associated with other wrist fracturesafter a fall on an outstretched arm Thisfracture is usually a dorsal cortex chipfracture best seen on a lateral view

Figure 78.13 Avulsion ture of the ulnar collateralligament insertion at thebase of the thumb, com-monly referred to as agamekeeper’s or skier’sthumb If the fragment iswidely displaced, a Stenerlesion can result, requiringsurgical intervention

frac-Figure 78.14 Rheumatoidarthritis of the wrist, demon-strating bony ankylosis ofthe carpus, ulnar deviation

at the MP joints, and ulnarstyloid erosions

Figure 78.15 Late toid arthritis There is marked

rheuma-MP joint destruction and rowing Weakening of theradial sagittal bands causesulnar subluxation of the ex-tensor mechanism and sub-sequent ulnar deviation ofthe MP joints

475Radiographic Findings

Figure 78.16 Rheumatoid tis in the fingers In contrast to os-teoarthritis, the IP joints are nar-rowed with characteristic erosions

arthri-Figure 78.17 An illustration of several of the common clinical features of matoid arthritis: symmetrical joint involvement, rheumatoid nodules, ulnar devia-tion of the MP joints, and swan neck deformity of the digits (IP hyperextensionand DIP flexion)

rheu-Chapter 79

Practical Plastic Surgery, edited by Zol B Kryger and Mark Sisco ©2007 Landes Bioscience.

Examination of the Hand and Wrist

Zol B Kryger

Observation

The hand should be observed in the resting position This is termed the tion of function The wrist will be slightly dorsiflexed, the MP joints will be in

posi-45-75˚ of flexion, the PIP joints in about 10˚ of flexion, and the DIP joints will be

in 0-10˚ of flexion Any alterations in the normal resting position should be noted

A single finger fixed in extension can be due to a flexor tendon laceration or rupture

A single finger in fixed flexion may be due to an extensor tendon injury If theabnormal flexion is chronic, flexor tendon contracture must also be considered.This can be seen in Dupuytren’s disease

The patient should be instructed to slowly make a fist by flexing the fingerstowards the palm The fingertips should point towards the scaphoid A finger frac-ture with rotational deformity can result in one finger overlapping another, or analteration in the axis of convergence

Sensory Exam

The hand receives sensory innervation from the median, ulnar and radial nerves

The most reliable method of testing normal sensory discrimination is the two-point discrimination test The minimal distance at which the patient can distinguish two

distinct points of pressure is recorded Two-point discrimination should be 2-3 mm

on the pulp of the fingers This value can vary based on the individual’s occupation

A measurement of greater than 5 mm is abnormal in most people

To test median nerve sensation, skin sensibility on the palmer surface of the firstthree digits should be evaluated Ulnar nerve injury will result in abnormal sensa-tion of the little finger and ulnar side of the ring finger Loss of radial nerve sensa-tion will result in loss of sensibility on the dorsum of the hand and in the first webspace In addition, any areas of numbness, tingling or other sensory abnormalitiesreported by the patient should be noted as this can provide clues as to the nerve thatmay be involved

Evaluation of Motor Nerve Function

The most consistent sign of median nerve injury is loss of thenar opponensfunction Patients will make a fist without the thumb and index finger folded intothe palm If the flexor pollicus longus (FPL), flexor digitorum superficialis (FDS)and flexor digitorum profundus (FDP) of the index and middle finger are flexingnormally, then the nerve injury has occurred distal to the take off of the anteriorinterosseous nerve

477Examination of the Hand and Wrist

Signs of ulnar nerve injury include flexor carpi ulnaris (FCU) paralysis, terosseous and thumb adduction loss with a weak “key pinch,” and FDP paralysis ofthe small and ring fingers A long-standing injury can present with the classic “clawhand” deformity In a low lesion of the ulnar nerve just above the wrist, there will bemore clawing of the 4th and 5th fingers compared to a high lesion at the elbow This

in-is known as ulnar paradox and in-is due to the fact that in a high lesion the flexors willalso be paralyzed

Patients with a radial nerve injury will be unable to extend their wrist or fingers.This can occur following humeral shaft fractures Injury to the radial nerve in theaxilla will result in paralysis of the extensor carpi radialis longus (ECRL) and brevis(ECRB), triceps and brachioradialis muscles These muscles will atrophy inlong-standing nerve injury Loss of ECRL and ECRB function leads to loss of wristextension

Muscle power is assessed on a scale of 0-5, with a score of 5 indicating full powerand a score of 0 being paralysis 1 is given for just a flicker of muscle contraction, 2for the ability to move with gravity eliminated, and 3 is the muscle strength neces-sary to lift a joint against the force of gravity A score of 4 is for muscle powerbetween 3 and 5

Flexor Tendon Evaluation

Separate evaluation of both FDP and FDS function is important Division ofthe FDS without injury to the FDP will not be noticeable in the resting posture.The FDS is evaluated by immobilizing the surrounding fingers in extension andhaving the patient flex the finger at the PIP joint FDS to the index finger isevaluated by having the patient perform a firm pulp-to-pulp pinch with the thumb

An injured FDS will cause pseudo mallet deformity of the distal phalanx (flexedDIP, extended PIP), whereas an intact FDS will result in a pseudo boutonnieredeformity of the distal phalanx (extended DIP, flexed PIP) FDP is evaluated byimmobilizing the PIP and IP joints and evaluating flexion of the isolated DIPjoint

The palmaris longus is present in 85-90% of patients It courses over the hamateand is identified by having the patient forcibly oppose the thumb and little finger.This tendon is expendable and can be readily used for tendon grafting procedures

Extensor Tendon Evaluation

Extension of each individual digit at each joint should be examined It is tant to remember that the juncturae tendinum located at the level of the MP jointsconnects the extensor tendons of extensor digitorum communis (EDC) Therefore,lacerations proximal to the juncturae may not impair digit extension due to theconnection to the adjacent digits Limitation of extension of the DIP joint of thefinger is most often due to rupture of the insertion of the extensor tendon into thedistal phalanx This type of injury will produce a mallet finger deformity If theextensor tendon is disrupted proximal to the PIP joint, a boutonniere deformitymay be produced due to hyperextension of the DIP joint by the taught lateral slips.Evaluation of extensor pollicus longus (EPL) function is performed by askingthe patient to place his palm flat on the table and to raise the thumb off of the table.Extension of the thumb alone is not an adequate test of EPL function since extensorpollicus brevis (EPB) and the intrinsic muscles of the thumb will contribute to itsextension

Intrinsic Hand Muscle Evaluation

The dorsal interossei are tested by asking the patient to abduct the fingers awayfrom the middle finger, whereas the volar interossei are evaluated by adduction ofthe fingers towards to the middle finger The lumbricals are tested by asking thepatient to flex the fingers at the MP joints while the IP joints are held in extension

Thumb Laxity

Instability of the MP joint of the thumb should be assessed Laxity should bedetermined by abducting the thumb in both extension and flexion Thumb laxity isnormally greater in extension and should be compared between the two hands Rup-ture of the ulnar collateral ligament (UCL) that connects the proximal phalanx ofthe thumb to the first metacarpal will result in excessive MP laxity This injury iscommonly seen in skiers, skateboarders, and anyone who falls on an extended thumbthat is forcefully abducted The acute injury is termed skier’s thumb, and the chronicinjury is referred to as gamekeeper’s thumb

Vascular Exam

The color of the digits should be observed, and any pallor, hyperemia or cyanosisnoted Capillary refill greater than 2 seconds is not normal Arterial inflow to the

hand is determined by palpating the radial and ulnar artery pulses The Allen test is

performed using the thumb and fingers to compress the radial and ulnar arteries atthe wrist The patient exsanguinates the hand by making a fist several times andthen opens the hand so that the fingers are in a relaxed and gently extended posi-tion The examiner then releases pressure from over the ulnar artery Capillary refilltime in the hand is noted A normal Allen test is refill in less than 5 seconds, andgreater than 5 seconds indicates an abnormal Allen test

Wrist Stability and Motion

Pronation and supination of the wrist are examined with the elbow flexed to 90°and held firmly to the sides in order to stop rotation of the shoulder From thisposition, there is usually about 90° of pronation and 90° of supination Flexion,extension, radial and ulnar deviation should all be compared between the two wristssimultaneously, and any discrepancies should be noted

Volar and dorsal stability are determined by the examiner exerting axial tractionwhile holding the patient’s forearm with one hand and the metacarpal heads withthe other Volar and dorsal displacement of the wrist in this position is minimal Ifwrist laxity is present during volar pressure, midcarpal subluxation may be due to aflexion deformity of the first carpal row (the VISI deformity) If laxity is notedduring dorsal pressure, a dorsal deformity (the DISI deformity) may be present

479Examination of the Hand and Wrist

index finger The thumb pulp will rest over the hamate The hook becomes moreprominent with wrist flexion

Dorsal Surface

The anatomic snuff box is located on the radial side of the wrist Its radial border

is EPB and abductor pollicus longus (APL; first dorsal compartment) The ulnarborder is EPL (third dorsal compartment) This structure is important because themost commonly fractured carpal bone, the scaphoid, lies below the snuff box Thedistal pole of the scaphoid can be palpated in the snuff box with the wrist in ulnardeviation The scapholunate (SL) joint is the most common site of carpal disloca-tion The examiner traces the third metacarpal proximally towards the wrist Theexaminer’s finger falls into a depression overlying the SL joint The lunate is thesecond most commonly fractured carpal bone It lies just ulnar to the SL joint It ispalpated with the wrist in flexion during which it is the most prominent area on thedorsum of the wrist Lister’s tubercle is an easily palpable prominence at the distalradius that lines up with the third metacarpal It is easier to palpate it during mildwrist flexion Recall that it separates the second and third compartments

Important Provocative tests

Tinel’s sign is a useful test for neuropathy If percussion at the site of nerve

entrapment produces tingling along the course of the nerve or in the digits supplied

by the nerve, the test is positive At the wrist, the volar carpal ligament can be percussed

to test for median nerve neuropathy (carpal tunnel syndrome) The test has a lowsensitivity (50-70%), but a high specificity (94%)

Phalen’s test is used to provoke median nerve compression It is performed by

having the patient hold both wrists in flexion for a minute by opposing the dorsum

of the two hands If this reproduces the symptoms, the test is positive It has asensitivity of 70-80% and a specificity of 80% The more rapidly the symptoms areproduced, the higher the specificity of the test

Finkelstein’s test is used to test for tenosynovitis of the first dorsal extensor

compartment (de Quervain’s disease) The wrist is braced in ulnar deviation whilethe thumb is passively adducted and flexed A positive test produces pain at the base

of thumb There may also be point tenderness over the radial styloid

The grind test is used to assess for arthritis of the carpometacarpal (CMC) joint

of the thumb, a common condition that produces pain similar to de Quervain’stenosynovitis The examiner exerts axial pressure on the thumb and grinds it againstthe first metacarpal against the trapezium A positive test produces pain In addi-tion, plain radiographs will show arthritic changes—a finding that will be absent in

de Quervain’s disease

The scaphoid shift, or Watson test, is used to test for SL instability or scaphoid

fracture, although it has a low sensitivity and specificity The examiner’s fingers areplaced dorsally on the distal radius, while the thumb is placed firmly on the scaphoidtubercle (on the volar surface) The other hand holds the metacarpals, and the wrist

is deviated ulnarly which places the scaphoid in extension As the wrist is moved inradial deviation, the scaphoid is blocked from flexing by the examiner’s thumb Ifthe SL ligament is injured, the scaphoid will move dorsally under the posterior mar-gin of the radius inducing pain when it touches the examiners fingers When pres-sure on the scaphoid is removed, the scaphoid goes back into position with a thunk

or clunk The test should be performed on the uninjured wrist for comparison

The screwdriver test is used to examine the triangular fibrocartilage complex

(TFCC) The examiner shakes the patient’s hand and performs alternating tion and pronation of the wrist (i.e., screwing and unscrewing motion) This mo-tion will usually cause ulnar-sided pain at the wrist if a TFCC injury is present.Decreased range of motion may also be apparent

supina-Pearls and Pitfalls

– Any patient with an acute injury should be asked the following questions:

• When did the injury occur?

• What was the mechanism of injury?

• What was the position of the hand and/or fingers during the injury?

• Was the environment clean or dirty?

• Have any medications been administered by the ER staff such as a local anesthetic?

• Is there a history of prior injury?

• What is the tetanus status?

– Palpation for specific tender spots is often the most painful part of the physicalassessment and should therefore be reserved for the end of the exam

– A patient complaining of chronic hand or wrist pain should be asked to strate the movements that most accurately replicate the pain

demon-– In order to avoid missing an important finding on the initial physical exam, it isuseful to follow an examination routine such as:

• Observation

• Vascular: Radial and ulnar artery, capillary refill, skin color

• Sensory: Median, ulnar and radial nerves

• Motor: Median, ulnar and radial nerves

• Flexor tendons

• Extensor tendons

• Intrinsic hand muscles

• Wrist stability and range of motion

• Palpation of bony landmarks

Chapter 80

Practical Plastic Surgery, edited by Zol B Kryger and Mark Sisco ©2007 Landes Bioscience.

Soft Tissue Infections

Zol B Kryger and Hongshik Han

Introduction

Infections of the hand can range from minor, superficial cases to infections ofthe deeper spaces of the hand that can potentially become limb-threatening andmust be treated aggressively Trauma is the major cause of hand infections, followed

by human bites and animal bites Staphylococcus aureus (S aureus) accounts for about

two-thirds of all hand infections

Clinical Presentation

Diagnosis

A thorough history is important The exact time and nature of the injury should

be ascertained since this will guide treatment For example, S aureus is often

impli-cated in home and industrial infections, whereas Gram-negative bacteria shouldalso be considered if the infection occurred on a farm setting Determination ofhand position during and after the injury is also important Accompanying symp-toms help determine how extensive the infection has become The age of the patient

is important as well Hand infections in children may involve different bacteria such

as oral flora and Gram-negative rods (e.g., H Influenza or pseudomonas) Table

80.1 lists the common hand infections and antibiotics used to treat them

Differential Diagnosis

There are a number of conditions that can simulate a hand infection: acute cific tendinitis (usually affecting flexor carpi ulnaris), gout or pseudogout, pyogenicgranuloma, pyoderma gangrenosum, metastatic cancer, and the necrosis from thebrown recluse spider bite, to name a few Radiographs are required in all suspectedhand infections to rule out gas in the soft tissue and occult fracture or osteomyelitis.The early hand infection may masquerade as ischemia Findings on exam mightinclude areas of patchy discoloration, edema, slow capillary refill and a mottled,cyanotic appearance Gross purulence and inflammation may not be observed Lateinfections developing 7-10 days after the initial injury indicates an insufficient localhost response against bacterial contamination The wound usually becomes fluctulantwith purulent discharge Late infections are seen more commonly in diabetics orimmunocompromised individuals (e.g., transplant recipients, chemotherapy recipi-ents, HIV, and other immune disorders)

cal-Treatment

The principles of treatment are similar in all hand infections They are rized in Table 80.2

The most common infections and their management are discussed below:

sys-Bites

Animal and human bites account for about a third of all hand infections Theynot only can cause tissue damage but also can lead to serious infections if not treatedproperly Human bites often cause infection due to the virulent microaerophilic

Streptococci, S aureus, and Eikenella corredens found in the human mouth.

Human Bites

Human bite wounds can be devastating The human mouth contains mixedflora that can synergistically infect and destroy soft tissues, tendons, joints, andbones For instance, a clenched fist that strikes a person’s mouth can result in a

Table 80.1 Hand infections and the empiric antibiotics of choice

Human bite S aureus, streptococci, anaerobes Cefazolin and penicillin or

Eikenella corredens amoxicillin/clavulonic acidDog/cat bite S aureus, S viridans, Bacteroides Cefazolin and penicillin or

Pasturella multocida amoxicillin/clavulonic acidTenosynovitis S aureus, streptococci, anaerobes Cefazolin and penicillin or

amoxicillin/clavulonic acidDeep space S aureus, streptococci, anaerobes Amoxicillin/clavulonic acidinfection Gram-negative rods or cefazolin and penicillinCellulitis S aureus, S pyogenes Nafcillin, oxacillin, or

cefazolinFelon or S aureus, anaerobes Cefazolin or dicloxacillinparonychia

Note: emerging bacterial resistance to cephalosporins may require the use of asecond- or third-generation agent

Table 80.2 Principles of hand infection management

• Incision and drainage of pus

• Debridement of necrotic tissue

• Antibiotics-first empiric (usually a two-drug regimen) then targeted based

on cultures

• Tetanus prophylaxis when indicated

• RICE (rest, immobilization, cold, and elevation)

• Early hand therapy

483Soft Tissue Infections

tooth penetrating the extensor tendon, metacarpal head or joint space In suchcases it is important to examine the hand with the fist in the clenched position.Early infections may present with nothing more than minimal swelling anderythema These can often be treated as an outpatient, with exploration, debride-ment, irrigation and oral antibiotics Advanced infections, however, can be severewith purulence and accompanying lymphangitis or lymphadinitis Untreated,irreversable damage to vital structures can occur At the first sign of severe infec-tion, the patient must be hospitalized and the infection treated aggressively withdebridement, drainage, irrigation, antibiotics, immobilization, and elevation Hu-man bite wounds to the hand should not be closed, but rather left open to healsecondarily The wound should be evaluated on a daily basis to ensure that it ishealing

Dog and Cat Bites

Dog bites account for 90% of all animal bites Dog bite wounds are often tions or avulsions of soft tissue, whereas cat bites are usually deep puncture wounds.Not all bites become infected Animal bites are less likely to progress to a clinicalinfection than human bites An infected animal bite presents as rapidly progressingcellulitis and swelling with drainage from the bite wounds The organisms frequently

lacera-seen in dog bites are S aureus, S viridans, Pasturella multocida and Bacteroides cies Cat bites have similar organisms with a large number of Pasturella multocida

spe-often present Treatment is similar to human bites Antibiotic coverage againstPasturella (penicillin) should be included

Paronychia

A paronychia is a soft tissue infection adjacent to the nail Bacteria enter thesurrounding tissue through the nail fold, usually after the patient pulls or bites ahang nail, or secondary to a foreign body at the site (such as a splinter) Conse-

quently, the infection will often contain oral flora in addition to S aureus If

discov-ered early, it can be treated with warm daily soaks, elevation and oral antibiotics.After the first 24 hours of infection, pus may develop under the nail fold In suchcases, treatment consists of elevating the nail fold off the nail to allow it to drain.Paronychia that fail this more conservative approach may require removal of the nailplate for adequate drainage to occur

Chronic paronychia occur in the immunocompromised; Candida albicans is the

most common organims involved It usually involves nail bed destruction with theresulting nail plate fragments acting as a foreign body This condition requires X-rays

to rule out distal phalanx involvement Treatment consists of excision of the mal nail fold with healing by secondary intention or removal of the nail and topicalantifungal therapy Tissue specimens should be sent for culture and pathology torule out an exotic infection or occult carcinoma/melanoma

Felon

A felon is an infection of the distal finger tip pulp, usually due to S aureus It can

develop after a puncture wound or as the result of a proximally-extending paronychia.Patients often complain of dependent pain due to the pressure build up of fluid in theconfined space of the pulp Because of the fibrous septa in the volar pad, a felon is aclosed space infection that must be incised and drained If the infection has not pointed,the incision should be made over the site of greatest tenderness Antibiotics and eleva-tion of the hand are also important When not treated adequately, a felon can spreadinto the phalanx, adjacent joint space, or flexor tendon sheath X-rays should be per-formed to evaluate for the presence of a foreign body

Deep Space Infections

The deep spaces in the hand include the thenar space, midpalmar space, webspaces, and subtendinous (Parona’s) space Deep space infections usually follow a

deep puncture wound, and S aureus is the most commonly cultured organism.

They require incision and drainage, antibiotics, splinting and elevation Care must

be taken not to injure the nearby neurovascular structures These infections are ten contained in a single space, but if neglected and allowed to spread they can form

of-a “horse shoe of-abscess,” involving severof-al deep hof-and spof-aces

Infectious Tenosynovitis

Infections of the tendon sheath are most commonly due to Gram-positive,

aerobic bacteria such as S aureus Human bites predispose to anaerobic organisms

as well Animal bites carry the additional risk of Pasteurella multocida infection.

Gonococcal flexor tenosynovitis is due to hematogenous spread of disseminatedgonorrhea

Diagnosis

Dr Kanavel described the cardinal signs of acute flexor tenosynovitis (Kanavel’ssigns):

1 Pain with passive finger extension

2 Tenderness over the entire length of the flexor sheath

3 Finger held in the semiflexed position

4 Swelling of the finger

Treatment

Acute flexor tenosynovitis is a serious condition that requires immediate ment In cases of nonsuppurative tenosynovitis, 24 hours of broad spectrum antibi-otics, splinting and elevation can be tried If the patient does not improve, tendonsheath irrigation is indicated Suppurative tenosynovitis is a surgical emergency, andtendon sheath irrigation is the mainstay of treatment A proximal incision is made

treat-at the level of the distal palmar crease proximal to the A1 pulley A distal incision ismade over the DIP joint distal to the A5 pulley The sheath is exposed, opened, andvigorously irrigated with antibiotic solution Postoperatively, a catheter can be left

in place distally and proximally to allow irrigation of the sheath Intravenous otics are also used, although the irrigation of the sheath is primary treatment Pa-tients are usually hospitalized for 2-3 days

485Soft Tissue Infections

Outcome and Complications

Two to three days following surgery, active motion exercises are initiated plete functional recovery usually occurs within 1-2 weeks Complications of flexortenonsynovitis include tendon necrosis, rupture, or adhesions, joint complications,osteomyelitis, deep space abscess and even amputation

Com-Pearls and Pitfalls

When performing any incision and drainage procedure, the location of theincision must be carefully considered to optimize the function and aesthetics oncethe wound heals For bite wounds, the site of penetration will often lead directly

to the location of the purulence, and the choice of incision site becomes obvious.For paronychia and eponychia, the space between the nail plate and overlying skinfold is usually the site of drainage In a deep space infection, make the incisionover the most fluctuant, inflamed area The same is true for a felon that has pointed.Otherwise, make a mid-lateral incision deep into the volar pulp to disrupt thesepta Avoid fish-mouth incisions since these can result in a fingertip deformityafter healing For suppurative tenosynovitis, a mid-lateral incision is an excellentchoice, since a Bunnel-type incision that breaks down can expose the underlyingflexor tendon sheath

3 Dellinger EP, Wertz MJ, Miller SD et al Hand infections Bacteriology and treatment:

A prospective study Arch Surg 1988; 123(6):745

4 Goldstein EJ Current concepts on animal bites: Bacteriology and therapy Curr ClinTop Infect Dis 1999; 19:99

5 Hausman MR, Lisser SP Hand infections Orthop Clin North Am 1992; 23:171

6 Moran GJ, Talan DA Hand infections Emerg Med Clin North Am 1993; 11:601

Chapter 81

Practical Plastic Surgery, edited by Zol B Kryger and Mark Sisco ©2007 Landes Bioscience.

Compartment Syndrome of the Upper Extremity

Zol B Kryger and John Y.S Kim

Introduction

Compartment syndrome of the upper extremity can occur in the arm, forearm,wrist or hand It is defined as an increased pressure build-up within an enclosedcompartment sufficient to impair muscle and nerve perfusion within that compart-ment In the upper extremity, it most commonly occurs in the forearm secondary totrauma Fractures of the humerus are the most common etiology

Relevant Anatomy

Arm

The arm contains two compartments: the anterior flexor compartment (biceps

and brachialis) and the posterior extensor compartment (triceps) The fascia ing and separating these two compartments is relatively weak, and consequentlyfluid accumulation in one compartment will usually make its way into the othercompartment and the surrounding subcutaneous tissues Furthermore, the com-partments of the arm communicate with the shoulder girdle, making compartmentsyndrome even more unlikely to occur

encas-Forearm

The forearm structures are contained within three compartments: an anterior

flexor (volar) compartment, a posterior extensor (dorsal) compartment, and the bile wad (superficial radial-dorsal side) These compartments do not communicatefreely with one another nor with the hand distally and the arm proximally Therefore,forearm compartment syndrome is more common than in the arm or hand

mo-Wrist and Hand

The wrist has one main compartment, the carpal tunnel Release of the carpal

tunnel should be performed at the time of forearm compartment release The partments of the hand are more numerous and complex than in the forearm There are

com-ten compartments: four dorsal interosseous, three volar interosseous, one thenar, one

hypothenar, and one adductor pollicis compartment In the fingers, the ligaments(Cleland’s, Grayson’s, and transverse retinacular) can also segregate the digit into com-partments, resulting in a compartment syndrome of the neurovascular bundle

Pathogenesis

A number of factors discussed below can lead to an increase in the pressure of acompartment, such as an accumulation of fluid within the enclosed space As thepressure increases above 35 mm Hg, capillary perfusion becomes compromised andischemia ensues A vicious cycle sets in, worsening the situation: the ischemia leads to

487Compartment Syndrome of the Upper Extremity

impaired venous return, increased capillary permeability and vasodilation, all of whichcause greater fluid accumulation and serve to increase the pressure even further

The tissues most sensitive to the resulting ischemia are nerve and muscle Greaterthan 6-8 hours of ischemia will cause irreversible nerve and muscle damage Thedeeper compartment muscles (such as flexor digitorum profundus) are usually af-fected first, and the central portions of the muscle belly are more susceptible due topoor collateral circulation

Etiology

Causes of compartment syndrome either limit the ability of the compartment toexpand in size or increase its volume In most instances, the etiology is multifacto-rial For example, a displaced supracondylar humeral fracture leading to forearmedema, combined with a circumferential cast that is too tight In the setting oftrauma, multiple injuries substantially increase the risk of developing compartmentsyndrome Compared to an isolated humeral shaft fracture, the combination of ahumeral and radial fracture raises the risk of compartment syndrome significantly Ifthere is a concomitant arterial injury, the risk can approach 50%

Factors that restrict the size of the compartment:

• Constrictive casts and dressings

• Prolonged external pressure during surgery (e.g., tourniquet)

• Prolonged external pressure during unconsciousness

• Eschar from a burn

Factors that increase the volume of the compartment:

• Fractures (usually closed) leading to edema or hemorrhage

• Spontaneous bleeding secondary to a coagulopathy

• Crush injury leading to edema

• Infection or snake bites leading to edema

• Edema from burns

• Edema from reperfusion injury, or following revascularization

• Edema from strenuous exercise

• Iatrogenic fluid infiltration

Clinical Diagnosis

The diagnosis of compartment syndrome is clinical Measurement of ment pressures should be used only as an adjunctive tool The signs and symptomsare usually progressive and include the following:

compart-• A swollen, tense compartment

• Digits in MP extension and PIP flexion

• Pain out of proportion to the underlying injury

• Pain with passive stretching of the involved muscles

• Paresthesias in the distribution of the involved nerves

• Impaired two-point discrimination test

• Motor weakness in the distribution of the involved nerves/muscles

• Intact pulses or dopplerable arterial signals

Compartment Pressure Measurements

As stated above, compartment syndrome is a clinical diagnosis and pressuremeasurements only aid in confirming the diagnosis In the uncooperative orobtunded patient however, an accurate exam is not possible, and objective pressure

determination can be of value if there is a high index of suspicion The normalcapillary perfusion pressure ranges from 20-25 mm Hg Several techniques areavailable for measuring compartment pressure; however they differ on the thresh-old pressure used to make the diagnosis of compartment syndrome

Whitesides’ method describes the use of needle manometery using readily

available supplies This technique considers a pressure within 20 mm Hg of thediastolic pressure as its threshold A modification of this method can be performedusing a standard arterial line connected to an 18 gauge needle inserted into thecompartment

The Matsen technique involves continuous monitoring of the compartment

pressure for up to 3 days It is similar to Whitesides’ technique An absolute pressurethreshold of 45 mm Hg is considered positive

Finally, the Murbarak method directly measures compartment pressure using a

wick (slit) catheter There are a number of hand-held devices available that rely onthis technique Any pressure above 30 mm Hg is considered highly suggestive ofcompartment syndrome

In the forearm, the needle should be inserted in the middle of each ment, which corresponds more or less to the middle third of the forearm In thehand, the pressure should be measured in the four dorsal and three volar interosseouscompartments, as well as in the thenar and hypothenar compartments on the pal-mar surface In the wrist, pressure should be measured in the carpal tunnel

compart-Management

Compartment syndrome is a surgical emergency Without timely compartmentrelease, irreversible damage will ensue Most studies indicated that the fasciotomyshould be performed within 12 hours of compartment syndrome onset It is contro-versial whether to perform a fasciotomy more than 48 hours after injury If the cause

of the compartment syndrome is due to excessive external pressure, this should beimmediately relieved All dressings and cast material should be removed since thisalone can significantly reduce compartment pressure and occasionally eliminate theneed for surgical decompression

Operative Treatment

The surgical release of the compartments is termed a fasciotomy Occasionally

a prophylactic fasciotomy is performed following revascularization of a limb thathas been ischemic for over 4 hours Skin incisions after fasciotomy are generallyleft open They may be loosely approximated to cover any exposed nerves Theincisions can be closed several days later or skin-grafted if direct closure is notpossible

Arm

Two separate incisions are required The flexor compartment is decompressedvia an incision extending from the acromion along a line that lies just medial to thelateral bicipital sulcus The extensor compartment is released using an incision thatextends proximally from the olecranon along the lateral side of the arm over triceps.Alternatively, both compartments can be released through a single incision extend-ing from the shoulder to the elbow crease along a line overlying the medial inter-muscular septum

489Compartment Syndrome of the Upper Extremity

Forearm and Wrist

Release of the flexor compartment and the mobile wad should be performedfirst since often this will reduce the elevated pressure in the dorsal compartment

An S-shaped skin incision is made, extending from proximal to the elbow creaseand into the palm (Fig 81.1) Thus, the carpal tunnel is released along with thevolar compartment After the skin and subcutaneous tissue have been incised,the deeper fascia (including the transverse carpal ligament) is incised and themuscles are mobilized The median nerve is identified and full release of anynerve compression is performed along its entire course If there is suspicion ofulnar or radial nerve compromise, these nerves should also be decompressed

If the dorsal compartment still has elevated pressures after volar release, a dorsalfasciotomy incision is made It begins from a point 2 cm lateral and distal to thelateral epicondyle and extends about 10 cm towards the center of the wrist

Hand

Decompression of all of the hand compartments requires multiple volar anddorsal incisions The dorsal and palmar interosseus compartments are approachedusing two dorsal incisions over the second and fourth metacarpals (Fig 81.2) Thethenar and hypothenar compartments are accessed through a longitudinal incisionalong the radial side of the first metacarpal, and the ulnar side of the fifth metacar-pal, respectively (Fig 81.2) The carpal tunnel is released using either the standardopen approach, or with an extended incision that can also allow Guyon’s canal to bereleased (for ulnar nerve decompression) Access to the adductor compartment can

be gained through the carpal tunnel release

Postoperative Considerations

In the immediate postoperative period, urine myoglobin levels should be tored since elevated levels can produce acute renal failure Myoglobinuria peaks severalhours after circulation is restored Prophylaxis and treatment consist of alkalinizingthe urine and keeping the patient well-hydrated A urine output of at least 1-2 ml/kg/

moni-hr should be maintained Serum creatinine phosphokinase (CPK) levels should also

be followed since extremely high CPK levels are also a risk factor for renal failure

Figure 81.1 The S-shaped fasciotomy incision for release of the volar compartmentand mobile wad of the forearm The incision extends from proximal to the elbowcrease and into the palm, releasing the carpal tunnel along with the forearm

The arm is dressed in a bulky dressing and kept elevated postoperatively Thepatient is brought back to the operating room after 3-5 days for wound inspectionand fasciotomy closure If direct closure is not possible, split-thickness skin graftsare used to cover the defect This can be done immediately or within 1-2 weeks.Active and passive hand motion exercises should be initiated as soon as possible tohelp limit stiffness and contractures

Complications

Unrecognized or undertreated compartment syndrome is likely to result in one

or more complications Even those cases that are recognized and treated in a timelyfashion can be complicated by one of the following:

• Wound complications such as infection, dehiscence, and hypertrophic scarring

• Intrinsic hand contracture secondary to necrosis and fibrosis of intrinsic handmuscles

• Volkman’s contracture of the forearm flexor muscles

• Scar contracture across the elbow or wrist leading to impaired joint motion

• Hand or arm dysfunction secondary to permanent muscle injury

• Renal failure secondary to rhabdomyolysis

• Neurologic sequelae

• Sensory nerve deficits

Pearls and Pitfalls

The diagnosis of compartment syndrome is challenging and requires a high index

of suspicion The clinical exam, underlying mechanism, and pressure measurements

Figure 81.2 Fasciotomy incisions over the second and fourth metacarpals forreleasing the dorsal and palmar interosseus compartments Longitudinal fasciotomyincisions along the radial side of the first metacarpal and the ulnar side of the fifthmetacarpal for release of the thenar and hypothenar compartments, respectively.The carpal tunnel is released via an extended incision which also allows access toGuyon’s canal and the adductor compartment

491Compartment Syndrome of the Upper Extremity

should be considered in making the diagnosis Many factors can contribute to edemaand swelling of the extremity without posing a risk for compartment syndrome Atense, edematous hand or forearm without pain or nerve deficits should be watchedclosely but is unlikely to represent compartment syndrome When in doubt, it is bet-ter to perform a fasciotomy, either prophylactic or therapeutic, than to wait until it istoo late

The fasciotomy should be done with extreme care to avoid injuring nerves thatare otherwise not at risk from the compartment syndrome itself The distal forearmfasciotomy incision at the wrist should be kept ulnar to the palmaris longus tendon

to avoid injury to the palmar cutaneous branch of the median nerve In the palm,the incision should be kept ulnar to the mid-axis of the ring finger

Various “minimal” incision approaches have been described for gaining access tomultiple compartments However, the risk of incomplete compartment release or ia-trogenic neurovascular injury is higher with a limited exposure It is worth noting that

in forearm compartment syndrome, release of the volar compartment will usuallysufficiently decrease the pressure in the dorsal compartment sparing a dorsal incision

4 Serokhan AJ, Eaton RG Volkmann’s ischemia J Hand Surg [Am] 1983; 8:806

5 Whitesides TE, Haney TC et al Tissue pressure measurements as a determinant forthe need of fasciotomy Clin Orthop 1975; 113:43

Contraindications for replantation:

• Significant systemic illness or comorbid conditions

• Concomitant life-threatening injuries

• Self-mutilation injuries

• Severe crush or avulsion injuries

• Extreme contamination

• Multiple level injuries

• Forearm or arm amputations with greater than 6 hours of warm ischemia time

Classification

Some authors classify the amputation by the flexor tendon zone (see Chapter90) An alternative classification of amputation level has been introduced by Tamai:Level I Amputation at the proximal nail fold

Level II Amputation at the DIP joint

Level III Amputation at the middle phalanx

Level IV Amputation at the proximal phalanx

Level V Amputation at the superficial palmar arch

Preoperative Considerations

Ischemia Time

Amputated parts should be cooled as soon as possible since they can toleratesignificantly longer “cold ischemia” than “warm ischemia” time Ideally, the partshould be wrapped in saline-soaked, cold gauze sponge and placed in a bag on ice.Digits can survive for 24-36 hours cold, compared to 8 hours warm A hand hasbeen successfully replanted after 54 hours of cold ischemia time The forearm cantolerate up to 10 hours of cold ischemia and 4-6 hours of warm ischemia.Radiographs of the amputated part and the residual extremity should be ob-tained to determine if there are any missing segments of bone The patient should

be consented for possible tissue grafting or free flap coverage in addition to tation Prior to surgery, the patient should be hydrated and warmed

493Replantation

Intraoperative Considerations

Preparation of the Amputated Part

Devitalized tissue is carefully debrided, and the vessels are dissected out underthe microscope Once a vessel is identified, it is marked with a tag Arteries areclosely inspected for signs of stretching or avulsion, which is suggested by acorkscrew-like appearance termed the “ribbon” sign Bruising along the course ofthe digital vessel can also be a sign of avulsion injury Nerves and tendons are iden-tified and tagged The exposed bone is then minimally debrided

Preparation of the Stump

After identification of the important vessels, nerves and tendons, the devitalizedsoft tissue of the stump is carefully debrided and irrigated with antibiotic solution.Large bone fragments are saved for possible grafting The proximal bone stump isdebrided In the palm or finger, adequate exposure of the structures to be repairedmay require Bruner zigzag incisions

The Order of Repair

The order in which structures are repaired varies The following outlines a monly used progression:

com-1 Bone shortening followed by rigid fixation—if ischemia time is an issue,

cir-culation should be restored prior to bony fixation

2 Flexor tendon repair—some authors will repair only the profundus tendon

3 Extensor tendon repair

4 Arterial anastomosis—at least one artery is usually required

5 Venous anastomosis—at least two veins for more proximal digital amputations.

Level I amputations can be replanted without venous anastomosis

6 Nerve repair—this is optional, and may be delayed for a secondary procedure

7 Soft tissue coverage—skin grafts are sometimes required, especially in avulsion

injuries Vein grafts can be harvested with overlying skin as a composite graft

Bone Fixation

Fixation of an amputated digit can usually be achieved with crossed Kirschnerwires passed retrograde through the amputated digit into the finger stump Ampu-tations through the proximal phalanx (Level IV) may require plate fixation for earlypostoperative mobilization Transmetacarpal, transcarpal, and forearm amputationsalso require screw and plate fixation This should be followed by periosteal repair,when indicated, to minimize tendon adhesion to the plates

Vascular Repair

The arteries and veins must be trimmed back until normal intima is apparent Inorder to minimize spasm, topical papavarine or concentrated lidocaine can be ad-ministered Alternatively, a Fogarty catheter can be used to break a spasm In crush

or avulsion injuries, a vein graft may be required Vein grafts can be taken from thedorsum of the foot, from the volar wrist, or from the dorsum of the hand Alterna-tively, the lesser or greater saphenous systems can be used The length of donor veinsshould be measured in situ since they shrink after harvest Vein grafts should not beexcessively long, since this can lead to kinking

Arterial repair is usually done first Prior to venous repair, the appearance of thereplanted part should be assessed for several minutes after completion of the arterialanastomosis to confirm adequate perfusion After the replant has warmed up, bleed-ing from the veins to be anastomosed should be brisk

Level I digital amputations can be replanted without a venous anastomosis Atleast two veins are required for proximal digital amputations If necessary, digitalveins can be transferred from an adjacent digit Venous drainage can also be achievedwith a proximally based cross-finger flap If the contralateral digital artery has retro-grade blood flow, it can be anastomosed to a vein to provide outflow Finally, if novein can be identified, the nail is removed and a heparin-soaked sponge is placed onthe nail bed, or leeches are applied to the tip of the digit

Tendon Repair

Debridement of the tendon ends should be minimized to avoid the need fortendon grafting Most surgeons repair the extensor tendons first, and many post-pone repair of the flexor tendons In Zone II flexor tendon amputations, some sur-geons will elect to repair only the FDP tendon A core suture technique is used; this

is described in detail in Chapter 90

Nerve Repair

Nerves should be repaired primarily whenever possible with 8-0 or 9-0 suture Adescription of primary nerve repair is discussed in the nerve repair chapter Whennecessary, nerve grafts can be taken from a number of sites: a nonsalvageable digit,the posterior interosseus nerve, the lateral femoral cutaneous nerve, the superficialperoneal nerve, and the sural nerve Vascularized nerve grafts have also been de-scribed Difficult nerve repairs may be delayed after the nerve ends are identifiedand tagged Sensory outcomes of digital replantation are improving Two-point dis-crimination of 10 mm or less has been reported

Soft Tissue Coverage

In order to avoid compression of the vascular anastomoses, the skin must beclosed in a tension-free fashion If this cannot be accomplished, a split-thicknessskin graft should be used In forearm or more proximal amputations, soft tissue lossmay be extensive, requiring local or free flap coverage

deglov-Hand and Forearm Amputations

Amputations through the carpal region have generally good functional outcomes.Transmetacarpal amputations, however, have a much poorer long-term prognosis.This is in part due to the many small vessels that are severed in these injuries In any

495Replantation

case, chronic swelling of the hand is common so many surgeons will release thecarpal tunnel and dorsal interosseous compartments at the time of surgery

Of all the tissue in the upper extremity, muscle is least tolerant of ischemia Inproximal amputations, restoration of blood flow is the first priority since more muscle

is involved Prophylactic forearm fasciotomies are often performed if warm ischemiatime is prolonged Proximal amputations will usually require secondary proceduressuch as nerve grafts and tendon transfers

Postoperative Care and Monitoring

At the completion of the procedure, the extremity should be placed in a well-paddedsplint without any circumferential dressings since swelling is inevitable The fingertipsshould be exposed so that they can be monitored postoperatively

The patient must be kept in a warm room with the extremity elevated above theheart A continuous axillary anesthetic block can help with pain control and act as achemical sympathectomy Aspirin should be given since it has a potent anti-plateleteffect Although many centers use some form of anticoagulation, no randomizedcontrol trials have demonstrated a benefit to any regimen The patient should behydrated with intravenous fluids to avoid hypotension

Monitoring the circulation after replantation is similar to a free-flap as discussed

in the chapter on free-flap monitoring Early detection of microvascular failure iscritical for salvage of the replant The most reliable means of monitoring a replanteddigit is a clinical exam by an experienced individual combined with pulse oximetry

or Doppler monitoring SpO2 values above 95% are normal; a saturation below85% indicates a venous problem, and a complete lack of signal indicates and arterialproblem Arterial and venous Doppler monitoring is used in many centers; bothpencil and laser Doppler can be used Finally, removal of the nail with monitoring ofnail bed bleeding provides a rudimentary means of monitoring arterial circulation

Outcomes

The most common early complications after replantation are bleeding, infectionand loss of the replant Late complications include cold intolerance, bony non-union, nerve or tendon adhesions requiring neurolysis or tenolysis, and late necrosis

of the replanted part

Centers with a highly experienced replantation team report survival rates of90-100% for digital replants Level II amputations generally do better than Level Iamputations In terms of sensory recovery, two-point discrimination of 10 mm orless has been reported in a number of series In both adults and children, persistentcold intolerance is common

Pediatric Replantation

Many surgeons agree that unless a contraindication exists, almost all tions in children should undergo replantation Long-term follow-up at 15 years hasdemonstrated return of normal sensation, strength, and bone growth in up to 90%

amputa-of digital replants in children Distal finger tip amputations have been shown tosurvive with composite grafting when microvascular replantation is not possible.Even in these cases, sensory recovery can be excellent, presumably due to spontane-ous neurotization In children, bone shortening should be undertaken with caution

to protect the epiphyseal growth plate so that the replanted bone will continue togrow normally

Pearls and Pitfalls

Three of the leading replant teams, the Kleinert-Kutz group, the Buncke group,and the Tamai group, have emphasized several important points in replantationtechnique:

• Bone shortening to reduce tension on the vessels, tendons, and nerves

• Repair of both the artery and vein before tourniquet release

• Heparin bolus after completion of the anastomosis

• Washing out the intravascular clots from crushed digits or hands

• The use of “spare parts” from unreplantable digits

• Transposing an amputated digit onto a different stump in cases of multiple digitamputations

Suggested Reading

1 Buncke Jr HJ Microvascular hand surgery—Transplants and replants—Over the past

25 years J Hand Surg 2000; 25A:415

2 Kim JYS, Brown RJ, Jones NF Pediatric upper extremity replantation Clin Plast Surg2005; 32:1

3 Kleinert HE, Jablon M, Tsai TM An overview of replantation and results of 347replants in 245 patients J Trauma 1980; 29:390

4 Lee BI, Chung HY, Kim WK et al The effects of the number and ratio of repairedarteries and veins on the survival in digital replantation Ann Plast Surg 2000; 44:288

5 Pederson WC Replantation Plast Reconstr Surg 2001; 107:823

6 Soucacos PN Indications and selection for digital amputation and replantation J HandSurg (Br) 2001; 26B:572

7 Tamai S, Michon J, Tupper J et al Report of the subcommittee on replantation JHand Surg 1983; 8:730

8 Weinzweig N, Sharzer LA, Startker I Replantation and revascularization at thetransmetacarpal level: Long-term functional results J Hand Surg 1996; 21:877

Chapter 83

Practical Plastic Surgery, edited by Zol B Kryger and Mark Sisco ©2007 Landes Bioscience.

Fractures of the Distal Radius and Ulna

Craig Birgfeld and Benjamin Chang

Introduction

The radius and ulna form the bony structure of the forearm They articulate withthe humerus at the elbow and the proximal carpal row at the wrist These bones formthe framework upon which the long flexor and extensor muscles of the forearm takeorigin The radius lies on the thumb side of the forearm (the “radial” side) and the ulnalies on the little finger side (the “ulnar” side) of the forearm The anatomic shape ofthese bones and their relationship at the joints provides for a high degree of mobility.However, the price of this mobility is propensity for injury and degenerative disorders

Anatomy

The elbow is formed by articulations between the radius and humerus and theulna and humerus The ulnar-humeral joint is a stable hinge joint, allowing onlyflexion and extension from 0-120 degrees The radial-humeral joint is a pivot joint,which allows the radius to rotate on the humerus This joint provides the mobilitywhich allows the pronation and supination of the forearm through 180 degrees.The radius and ulna are joined by an interosseous membrane, which is flexibleenough to allow rotation of the radius around the ulna in pronation and supination,but strong enough to tether the two bones in a stable relationship Pronator andsupinator muscles course between the two bones and the long flexor and extensormuscles of the wrist and fingers originate from these bones in the forearm At thewrist, the radius and ulna support the proximal row of carpal bones The radiusarticulates with the lunate and scaphoid at the lunate fossa and the scaphoid fossa.Ligaments join the scaphoid and lunate to the radius and these articulations can also

be the source of arthritic pain The distal ulna articulates with the triquetrum throughthe triangular fibrocartilage complex (TFCC) The radius and ulna meet at the sig-moid notch and are joined by the TFCC forming the distal-radial-ulnar-joint (DRUJ),

a frequent site of injury and arthritis The ulna styloid lies most distally and laterallyand is frequently involved in fractures of the distal radius

Radiographs

Relationships seen on normal radiographs are important to remember as thesewill be disrupted in fractures to the distal radius and ulna All radiographs of thewrist should be evaluated for ulnar variance, inclination and volar tilt

• Ulnar variance: on the normal AP view, the distal ulna is within ± 1-2 mm of

the distal radius (Fig 83.1)

• Inclination: the radius tilts toward the ulna at an angle of 22˚ when measured

from a line perpendicular to its long axis on AP view (Fig 83.1)

• Volar tilt: on lateral view, the radius tilts in a volar direction 11˚ when measured

from a line perpendicular to its long axis (Fig 83.2)

Traumatic disruptions of these relationships can destroy the normal kinematics

of the wrist and lead to reduced range of motion and degenerative arthritis

Fractures

A variety of fractures can occur in the radius and ulna after the common matic history of, “fall on an outstretched hand” These are amongst the most com-mon skeletal injuries and occur more frequently in children and the elderly Fractures

trau-of the distal radius are best described in terms trau-of their comminution, articular volvement, displacement and angulation with particular attention paid to the mea-surements of ulnar variance, inclination, and volar tilt Eponyms are frequently usedfor expediency, though these can lead to confusion for inexperienced evaluators.Fractures of the ulna are often multiple and can have varying degrees of clinicalsignificance Recall that the radius and ulna essentially form a ring between theelbow and wrist and, as is seen with the mandible, a fracture of one side of the ringwill usually result in a fracture at the other

in-The most common fracture, is a dorsally angulated, extra-articular fracture of the distal radius, otherwise known as a Colles’ fracture A Smith’s fracture is a volarly

Figure 83.1 An AP radiograph showing

normal ulnar variance of +2 mm and

normal radius inclination of 22˚ These

two terms are defined in the text

Figure 83.2 A lateral graph demonstrating the normal

radio-11˚ volar tilt of the radius

when measured from a line pendicular to its long axis