Tổn thương Ramp: Ramp lesion, Forget me not

Ramp lesion (Tổn thương Ramp sụn chêm trong) là một tổn thương rất thường gặp đi kèm với tổn thương Dây chằng chéo trước của gối, có thể lên đến 32% tuỳ thuộc nghiên cứu. Tuy nhiên Ramp lesion rất thường dễ bị bỏ sót. Tổn thương sừng sau sụn chêm trong (tên khác) thường không thể chẩn đoán qua lâm sàng và ngay cả trên MRI, việc chẩn đoán phụ thuộc vào việc Nội soi có thể thống (Systemic arthroscopy). Bỏ sót Ramp lesion có thể gây mất vững khớp gối, gây đau và tăng tỷ lệ mổ lại. Điều trị Ramp lesion thường thách thức về kỹ thuật và dụng cụ. Mong bài share này sẽ hữu ích cho các bạn để điều trị tổn thương sừng sau sụn chêm trong khớp gối tốt hơn.

BE CAUTION!!

Not-Fun Fact

•PHMM + ACL up to 30.9% by arthoscopic findings.

(Chahla, Dean et al 2016, DePhillipo, Moatshe et al 2019, Hatayama, Terauchi

Oh!!! Why ‘Forget me Not’?

Clinical Examination

• neither sensitive nor specific

MRI

• low sensitivity (75.8%); low specificity (71.7%) (Kim et al, 2020)

• Multiple factors cause false negative (Bollen et al, Grief et al, 2017)

Arthroscopy

• Significantly underdiagnosed arthoscopically (40% without

transnotch view) (Sonnery-Cottet et al)

• Arthroscopic exploration: 60% 1st, 23.2% 2nd and 16.8% 3rd

(Sonnery-Cottet et al, 2014)

• Anatomy and Function of PHMM

• What is Ramp lesion ?

• MRI and classification of Ramp lesion

• Sequences of diagnosis

• Treatment of Ramp lesion

• Take home message

What is it?

Semilunar

Posterior horn of medial meniscus

The roots anchor to tibia, the body attaches to capsule and tibia!

DePhillipo et al, AJSM Vol 47, No 2, 2019 Greif et at, Skeletal Radiology, 2020

Mensical sectional 3 zones

Ramp rarely related to zone 2 and 3

What is RAMP?

- Tear or disruption of the

peripheral meniscal

horn of medial meniscus

How does it function?

- 88-N anterior tibial load,

- internal and external rotation torques of

5 Nm

- a simulated pivot-shift test of10-N valgus

f orce coupled with 5-Nm internal rotation

Making the Meniscocapsular lig lesion

Making the Meniscotibial lig lesion

Open posterior approach Identify the MTL Repair the MTL with 2

suture anchors

Anterior tibial translation

IR torque

ER torque

Pivot shift test

Conclusion and Extension

• MCL, MTL increase ATT, IR, ER in ACL-deficiency

• Pivot shift was only restored when performed ACL + meniscocapsular and meniscotibial repairà ACL + high-grade Lachman/pivot shift test

à suspected for Ramp lesion

• Play role in knee stability

• Lesion of the PHMM increases forces in the ACL by 50 %

(Papageorgiou et al, 2001) (unpublished data, C Edgar, MD, PhD, 2015)

To improve preoperative diagnosis

MRI

findings

MRI classification

Type 1: Meniscocapsular tear Type 1: Meniscocapsular ligament tear

Type 2: Partial superior tear Type 2: Partial superior peripheral meniscal horn tear

Type 3: Partial inferior tear Type 3A: Partial inferior peripheral posterior horn

meniscal tearType 3B: Meniscotibial ligament tearType 4: Complete tear Type 4A: Complete peripheral posterior horn meniscal

tearType 4B: Complete meniscojunction tearType 5: Double tear Type 5: Peripheral posterior horn meniscal double tear

Type 1:

Type 1: Meniscocapsular tear Type 1: Meniscocapsular ligament tear

• MC separation, MM, MT intact

• Best seen in T2: vertical line reaching the superior articular surface

• Visible (+), Mobile: Low

• Concominant injuries of contrecoup mechanism

MRI

classification

Type 2 Thaunat et al Grief et al, 2020

Type 2: Partial superior tear Type 2: Partial superior peripheral meniscal horn tear

• Transnotch view: red-red zone MM tear, MC and MT intact

• Vertical line reaching to superior articular surface in redred MM

• Visible (+), Mobile: very low

• suspected when probeà PM portion needed

Type 3 Thaunat et alType 3: Partial inferior Grief et al, 2020

tear Type 3A: Partial inferior peripheral posterior horn meniscal tear

• MT-MM tear, MT and MC intact

• Vertical oblique line to inferior articular surface of MM

• Visible (-), Mobile: High

Histological staining:

Meniscocapsular (*) and meniscotibial ligament (#) PHMM attachments showed similar structure, cell density, and fiber directionality, with no qualitative difference in the makeup of their collagen matrices across all specimens.

Conclusion:

The anatomy of the area where a medial meniscal ramp tear

occurs revealed that the 2 posterior meniscal attachments merged

at a common attachment on the PHMM Histological analysis

validated a shared attachment point of the meniscocapsular and

meniscotibial attachments of the PHMM

Clinical Relevance: The findings of this study provide the anatomic

foundation for an improved understanding of the meniscocapsular

and meniscotibial attachments of the PHMM, which may help

provide a more precise definition of a meniscal ramp lesion

Type 3 Thaunat et alType 3: Partial inferior Grief et al, 2020

tear Type 3B: Meniscotibial ligament tear

• MT ligament is torn, MM and MC intact

• Visible (-), Mobile: High

• Often cocominant with contusion of PM corner of tibia (contrecoup)

• Meniscal extrusion

Type 4 Thaunat et al Grief et al, 2020

Type 4: Complete tear Type 4A: Complete peripheral posterior horn

meniscal tear

• Complete longitudinal vertical tear of redred MM, MT and MC intact

• Linear high T2 extending from superior to inferior articular surface

• High healing potential after repair à aggressive repair

• Visible (+), Mobile: Very high

Type 4 Thaunat et alType 4: Complete tear Grief et al, 2020 Type 4B: Complete meniscojunction tear

• Complete tear of junction the MC and MT attach to the post horn

• Linear high T2 from superior to inferior articular surface with disruption of the capsular ligaments

• Visible (+), Mobile: very high

• Bone marrow edema (PM corner of tibia)

• Not sharing the same healing capacity with 4A à need more extensive repair

Type 5 Thaunat et alType 5: Double tear Grief et al, 2020 Type 5: Peripheral posterior horn

meniscal double tear

• Two tears within redred MM, MT and MC intact

• Two parallel linear high T2 extending from superior to inferior articular surface in redred zone of PHMM

• Visible (+), Mobile: very high

• Conconinant with tibial anterior translation

• Difficulty in repairing

MRI has low sensitivitive

The diagnostic sensitivity of MRI in detecting ramp lesions

is suboptimal, particularly in the presence of ACL rupture,

due to a variety of reasons

First, MRI has long been established to have reduced sensitivity for medial meniscal pathologies

in the context of ACL tears, though this also applies to lateral meniscal pathologies as well [40] Second, because the knee is in near full extension during imaging studies, meniscocapsular separation is reduced to a near minimum, making it difficult to distinguish meniscocapsular separation from non-displaced peripheral vertical longitudinal tears of the posterior horn on MRI [26] This mechanism shares similarity with how reduced bucket-handle tears may also be missed on MRI [41] Finally, the type of MRI interpreter plays a role in diagnosis, as board-

certified musculoskeletal radiologists diagnose ramp lesions more frequently than general radiologists [37] However, a meta-analysis by Koo et al demonstrated that when the knee is in neutral position (30 degrees of flexion) and imaging is read by a musculoskeletal radiologist, the pooled sensitivity for MRI stands at 71%, which presents opportunity for substantial

improvement [37].

Risk factors

2020

• Retrospective cohort btw 6/2011 to 9/2019

• Diagnosed with MRI and tracking on risk factors

• Confirmed by arthroscopic operation with 4 steps

(1) AL portal

(2) trans-notch with 30 degree scope;

(3) with 70 degree scope;

(4) PM portal: direct exploration

Risk factors

Bone contusion • Still CONTROVERSIAL in some reports!!

• Increased the number and location of bone contusion ~ prevalence of MM, LM, MCL injuries

• Bone contusion on the MTP most ~ ramp lesion

(Kaplan et al, ; Dephillipo et al, )

• OR 4.201

• Mechanism: pivot-shift mechanismimpaction MFC

>< MTP by compensatory varus alignment and IR of the femur after initial injury

Varus alignment

• > 3 degree

Time from injury to surgery

• >= 3 months, OR 4.818, 95%CI 2.158-10.757 (Kim et all, 2020)

• Agreement in other reports (Liu et al, Sonnery-Cottet et al)

• Mechanism: ACL injuries -> laxity and ant tibial translation à MM as

a wedge bt posterior tibia and femoral condyle > highstress loading

-> secondary PHMM lesions

Okazaki et al

• Increased medial tibia slope of the MTP ~ decreased resistance to displacement of the tibia à incrasd stressloading to PHMM

Medial tibial slope and Medial meniscus slope

• Cutoff: MT slope >7.1 degree

MM slope > 5 degreeMedial-to-lateral slope asymmetry > 0.4 degree

• As LT slope ~ PL root tear

• Steeper MT slope +/- varus alignment à

Tibiofemoral rotation and anterior

translation à excessive posterior sliding of MFC after initial pivot-shift injury

(contrecoup) à increased stress loading –Ramp

Risk factor equation and UAC

• Risk score= -4.565 + (1.435 x bone contusion on MTP) + (0.85 x varus alignment) + (0.254 x medial tibial slope) + (0.381 x medial meniscal slope) + (–0.255 x lateral tibial slope) + (1.572 x time from injury to surgery)

• 75.8% sen, 71.7% spe, 58,5% PPV, 84.9% NPV, regardless of direct (+) findings in MRI

• Cutoff >-0.492

• A diagnostic tool

Systemic arthroscopic outcome

• Kim et al 2020, found 34.5% rate following systemic

arthroscopic with 4 steps

• Relatively higher than previous studies

• 42%- 52% found via PM explorations after sequential

arthroscopic evaluation

• NECESSARY: sequential arthroscopic exploration

protocol should be routinely performed

PM

70 scope Transnotch

AL

Sequences of diagnosis

2014

• Case series, LOE 4

• Consecutive series of 302 ACL

reconstructions

• Results: 41.4% has medial meniscal tear; 60%

in meniscal body at first stage; 23.2% at

second stage; 16.8% at third stage

70 scope is unnecessary !!!

Clin Sports Med 39 (2020) 69–81 https://doi.org/10.1016/j.csm.2019.08.010

No consensus !!!

Ramp lesion need to be repair?

Left in place

• Stable Ramp lesion:

• repair at the time of ACL reconstruction does not have clinical benefit (Balazs et al,

2020)

• medial meniscal tears associated with ACL rupture can be asymptomatic and can

result in good healing even without meniscal repair (Shelbourne and Rask et al, 2001)

• Ramp lesion <15 mm

• 2-year follow up showed no significant difference in outcomes between

trephination/abrasion and meniscal repair (Liu et al, 2017)

Partial meniscectomy

• Irrepariable ramp lesion (Sonnery-cottet et al, 2014)

• All-inside suture with hook (n =23),

• Hybrid technique (hook + in–out) (n = 16) 4

Li et al, 2015

Chen, 2015 Trans-notch (23)(128)

Thaunat et

al, 2016 Trans-notch view (n= 132)

• All-inside suture with hook (n =81),

• Hybrid technique (hook + out–in or FasTFix (n=51) 4Liu et al,

2017 Posteromedial portal (n= 73)

• All-inside suture with hook with two posterolateral portals (n= 40) 2Keyhani et

al, 2017 Trans-notch view(n=128)

• All-inside suture with hook with posterolateral and

All-inside suture with hook

(Ahn et al, 2004; Sonnery-Cottet et al, 2020)

• For MM-type ramp leasion (Ahn et al, 2004)

• No.0 absorbable monofilament suture (polydioxanone)

Healing after 46 days

Suture sequence in medial meniscus posterior horn double longitudinal tear (Ahn et al,2004)

• Case series, n= 132, LOE 4

• All pts repaired by 25 degree Suture Lasso +/- hybrid (no.2 nonresorbable braided composite suture)

• Within rim <3mm (redred zone & capsulomeniscal

junction)

• 3-5mm unstable redwhite zone

• 2 groups: limited tear, and extended tear

• Success (78/81, 45/51)

• resection or revision of the repair as the endpoint

• No specific complication, except 2 hematoma

Noticable Complication- Failure

• Cleft by the path of Suture

Lasso + no.2 unabsorbable suture in whitewhite zone

All-inside FasT-Fix (Chen et al, 2016)

• Use for peripheral ramp lesion than

meniscal ramp lesion

• Classify into 3 types:

(A) Meniscotibial ligament ~ type IIIB

(B) Meniscocapsular ligament ~ type I

(C) Both ligament ~ type IVB

Technique (Negrin et al, 2018) in case of MLT

Teichnique

(A) Meniscotibial ligament ~ type IIIB

(B) Meniscocapsular ligament ~ type I

• Go above the MM

• First inplant: inserted obliquely to

joint capsule above MM

• Second implant: introduced via

red-red MM to MC lig

(C) Both ligament ~ type IVB

Two sutures were used to repair the superior

and inferior side of the meniscus

simultaneously

• 8/2010 - 12/2014, 46 knees -combined ACL injury and ramp lesion (18 MLT, 13 MCT,

15 combined)

• Secondlook @ 32 months, 87% complete healing, 10.8% incomplete healing, 2.1% failed

• In 10.8% (4 cases),

• 1 had combined with redred zone tear à repeated repair w meniscal fixator

• 3 had a cleft at the repair site à rasp refresh

• 1 had mid-meniscal radial tear à meniscectomy

• 2.1% failed (1 case), due to poor ACL tension à ACL revision and meniscectomy

Postoperative rehabilitation

• Immediate passive joint movements from 0° to 90°

• Non-weight bearing or toe-touch weight bearing for at least 2 weeks

• Full weight bearing after 4–12 weeks from surgery

• Use of brace in 181 (41%) of cases and was not specified in 328 (64.4%) cases

• At 6 weeks from surgery, a full range of motion

Take home message

• Clinical examination and MRI is not really realiable any time.

• Risk factors could be an additional diagnostic tool.

• ‘Systemic arthroscopy’ is needed to explore ramp lesion

• Most ramp lesion need to be repair if possible.

• Techniques are challenging.

• Asorbable > Unarsorbable suture.

Thank you for your attention!!