Meniscus Tear — ABOS Oral Boards Preparation
What examiners expect and how to prepare
Clinical Scenario
A 30-year-old right-hand-dominant male firefighter presents to your clinic with a 3-week history of right knee pain, intermittent locking, and swelling after a twisting injury on a wet floor while carrying equipment. He felt something catch in his knee and has had mechanical symptoms since — his knee intermittently locks in flexion and he has to manipulate it to regain extension. He has no prior knee injuries. On exam, he has a small effusion. There is joint line tenderness medially. McMurray test produces a palpable click and pain with tibial external rotation and valgus stress. Thessaly test at 20 degrees is positive. Lachman and anterior drawer are negative. He has full range of motion when unlocked but reports two episodes of true locking in the past week.
MRI of the right knee shows a bucket-handle tear of the medial meniscus with the displaced fragment flipped into the intercondylar notch. The ACL and PCL are intact. There is no articular cartilage damage. The lateral meniscus is normal. The tear extends from the posterior horn through the body of the meniscus, involving red-red and red-white zones.
You performed arthroscopic meniscal repair using an inside-out technique with vertical mattress sutures. The tear was reduced from the notch, freshened at the edges, and repaired with 4 sutures. The repair was stable to probing. Post-operatively, the patient was placed in a hinged knee brace locked in extension for weight-bearing, with immediate motion from 0-90 degrees allowed during non-weight-bearing exercises. Full weight-bearing without brace was allowed at 6 weeks, with return to full duty at 4 months.
What Examiners Look For
- Data gathering: Mechanical symptoms (true locking versus catching) are the key history findings — define the difference and explain their significance.
- Diagnosis: Describe the McMurray test technique precisely — hand position, force direction, and what constitutes a positive test.
- Treatment plan: Why repair over partial meniscectomy? Discuss vascularity zones and how tear location and pattern determine repairability.
- Technical skill: Inside-out versus all-inside versus outside-in — when do you use each technique and why?
- Applied knowledge: What is the long-term consequence of total meniscectomy? Discuss the meniscus as a load distributor and its relationship to arthritis.
- Complications: What is the failure rate of meniscal repair? How do you evaluate a potentially failed repair — clinical versus MRI?
Common Pitfalls
- Recommending meniscectomy for a repairable tear in a young patient — the examiner is testing whether you preserve tissue.
- Not knowing the vascular zones — red-red, red-white, and white-white — and how they predict healing.
- Describing a repair technique you have never performed — examiners can tell when the description is rehearsed versus experienced.
- Forgetting to discuss the associated ligament exam — a meniscal repair with an ACL-deficient knee has a higher failure rate.
- Not knowing that a bucket-handle tear with a locked knee is an indication for urgent (not emergent) surgery.
Key Classifications
Related Scenarios
Free — takes 3 minutes