Meniscus Repair — How It Works, Benefits & Recovery — Procedure Guide, Recovery & Risks | MyMedicPlus

Meniscus repair is an arthroscopic surgical procedure that re-approximates and sutures a torn meniscal cartilage in the knee joint, preserving the meniscus and restoring its critical mechanical functions. The medial and lateral menisci are C-shaped fibrocartilaginous structures that distribute load, absorb impact, stabilise the knee, lubricate the joint, and serve as secondary stabilisers during rotation. The medial meniscus bears 50% of the medial compartment load and the lateral meniscus 70% of the lateral compartment load. Meniscal tears are the most common knee injury requiring surgery, occurring most frequently in young athletes during pivoting sports (football, basketball, skiing) and in older adults through degenerate failure of an ageing meniscus. Repair — as opposed to partial meniscectomy (excision of the torn fragment) — preserves meniscal tissue and is now strongly preferred for suitable tears because long-term follow-up studies demonstrate that total or subtotal meniscectomy accelerates knee osteoarthritis, with 14-year data showing 74% of post-meniscectomy knees developing significant radiological osteoarthritis. The goal of arthroscopic meniscus repair is to stimulate intrinsic healing by reducing the tear and holding it in close apposition with sutures, allowing fibrovascular tissue ingrowth from the peripheral vascular zone. Healing rate depends critically on tear location, pattern, chronicity, and vascular supply.

Meniscus repair is indicated for tears with characteristics that predict satisfactory healing potential. The most favourable tear morphology is a vertical longitudinal (bucket-handle) tear in the peripheral vascular zone (red-red zone, outer third of the meniscus) where blood vessels from the peripheral capillary plexus can support healing. Other repair-amenable patterns include unstable radial tears, ramp lesions at the posterior menisco-capsular junction (medial meniscus), and horizontal cleavage tears in young patients. Key patient selection criteria include: age typically under 40–45 years (though repair is considered in older patients for large peripheral tears), acute tears less than 6–8 weeks old (chronic tears have less healing capacity), tear length greater than 10 mm (smaller tears may heal conservatively), intact articular cartilage (significant chondral damage predicts poor outcomes), and concurrent ACL reconstruction (ACL deficiency causes increased meniscal stress, and concurrent ACL reconstruction provides synovial fluid, fibrin clot, and cytokines that enhance meniscal healing — repair combined with ACL reconstruction has significantly higher healing rates than repair in isolation). Tears that are unsuitable for repair — inner white-white zone tears with no blood supply, complex degenerative tears in older patients, macerated or very small tears — are treated with partial meniscectomy.

Arthroscopic meniscus repair is performed under spinal or general anaesthesia with a thigh tourniquet to provide a bloodless field. Two or three small portal incisions of 5–10 mm allow introduction of an arthroscope (camera) and working instruments into the knee joint. The joint is irrigated with saline and all compartments systematically inspected. The tear is identified, its morphology and vascular zone determined, and its reducibility confirmed (the tear can be reduced and held in position). The tear edges are prepared by rasping or trephination to stimulate vascular access. Three principal suture techniques are used depending on tear location and surgeon preference. Inside-out technique: a curved cannula is placed arthroscopically and sutures are passed through the meniscus from inside the joint to outside where they are tied over the capsule through a small skin incision; excellent for posterior horn and body tears but requires a separate posteromedial or posterolateral skin incision for suture retrieval. Outside-in technique: a spinal needle is placed percutaneously from outside the capsule into the joint and used to pass sutures through the tear; commonly used for anterior horn tears. All-inside technique: a cannulated device loaded with implant-mounted sutures is inserted arthroscopically and deployed from inside the joint without any accessory incision; modern second-generation all-inside devices (Fast-Fix 360, Meniscal Cinch) provide secure meniscal fixation comparable to inside-out sutures with shorter operative time and no accessory incision risk. Three to five sutures per centimetre of tear length are placed to achieve stable repair.

The primary long-term benefit of meniscus repair over partial meniscectomy is preservation of meniscal tissue and its load-distributing function, which significantly reduces the rate of knee osteoarthritis development. Multiple long-term follow-up studies demonstrate that knees with intact or repaired menisci have substantially less osteoarthritic progression than those with partial or total meniscectomy: the Manzione series showed 64% good-to-excellent clinical results at mean 8-year follow-up after repair, with significantly less osteoarthritis progression than age-matched meniscectomy controls. For young athletes, successful repair enables return to competitive sport at the pre-injury level in 75–85% of cases — an outcome not achievable after the onset of meniscectomy-induced compartment degeneration. The arthroscopic approach produces minimal tissue trauma: 2–3 small portal incisions, day-case surgery, and rapid return to partial weight-bearing and range of motion within days of surgery. For ACL-concurrent cases, simultaneous repair and reconstruction in one anaesthetic avoids two separate operations. Successful meniscal repair also delays or avoids the need for subsequent joint replacement surgery in young patients — a critical consideration given that knee replacements in those under 50 have higher revision rates and more limited longevity than those performed later in life.

The principal complication of meniscus repair is re-tear or failure to heal, occurring in 10–25% of cases across the literature and requiring subsequent partial meniscectomy. Re-tear rates are higher for complex tears, white-red zone tears, isolated repairs without ACL reconstruction, and in older patients. Clinical failure (persistent pain and mechanical symptoms) without confirmed imaging failure occurs in a further 10%. Knee stiffness (arthrofibrosis) is a significant risk if rehabilitation is too aggressive or if range-of-motion restoration is neglected; it is managed with physiotherapy, manipulation under anaesthesia, or arthroscopic lysis of adhesions. Nerve injury from inside-out sutures placed medially carries saphenous nerve risk (medial repair) and common peroneal nerve risk (lateral repair), causing sensory disturbance or rarely foot drop; the accessory incision for suture retrieval must be placed precisely to avoid these structures. Infection (arthroscopic joint infection — septic arthritis) occurs in less than 0.1% of arthroscopic procedures and is a serious complication requiring urgent washout and intravenous antibiotics. Blood clots (DVT) require prophylaxis with aspirin or low-molecular-weight heparin during the non-weight-bearing period. The prolonged rehabilitation protocol (3–6 months) is itself a risk of non-compliance — patients who return to sport prematurely before biological healing is confirmed face high re-tear risk.

Meniscus repair requires a more conservative rehabilitation protocol than partial meniscectomy to protect the healing tissue. Non-weight-bearing with crutches and a locked straight-leg brace is maintained for 4–6 weeks in most protocols. The rationale for non-weight-bearing is that compressive and shear forces across the meniscus during full weight-bearing in the early healing phase disrupt the fibrovascular repair tissue before it matures. At 4–6 weeks, progressive weight-bearing is introduced with the brace unlocked. Physiotherapy progresses through four stages: phase 1 (weeks 0–6) passive range of motion, quadriceps activation, and straight-leg raises; phase 2 (weeks 6–12) closed-chain strengthening, proprioception, stationary cycling; phase 3 (weeks 12–20) running, lateral movement, sports-specific agility; phase 4 (months 5–6) sport-specific training and return-to-sport criteria assessment. Return to competitive sport is cleared only when: full range of motion is achieved, quadriceps strength symmetry exceeds 90% (measured by isokinetic dynamometry or single-leg hop tests), no effusion or residual pain, and MRI at 6 months confirms healing with no residual signal abnormality through the repair site. Return to desk work is possible at 2 weeks; driving at 4–6 weeks (right-side repair). Long-term sporting activity with high-impact pivoting should be balanced against the risk of re-tear and discussed with the patient.