Partial meniscectomy — medial or lateral — is an arthroscopic operation to trim and remove the damaged portion of a torn meniscus while preserving as much healthy tissue as possible. It is performed separately for the medial (inner) or lateral (outer) meniscus depending on which side is torn.
The operation is performed arthroscopically through two or three small incisions. The torn, unstable fragment of the medial or lateral meniscus is identified and trimmed back to a stable rim using motorised shavers and small instruments. The remaining healthy meniscus is preserved. The lateral meniscus is particularly important for load distribution, so preservation is emphasised even more strongly on the lateral side. The operation takes 20–40 minutes.
Partial meniscectomy is recommended for symptomatic tears causing mechanical symptoms (locking, catching, giving way) that have not responded to physiotherapy, particularly tears in the avascular inner zone where repair is unlikely to heal.
Physiotherapy, activity modification, anti-inflammatory medication, and time. Many degenerative tears improve without surgery. Meniscal repair is preferred when the tear pattern and location allow it.
MRI to assess the tear. Day-case procedure.
Relief of mechanical symptoms in approximately 85–90% of patients. Quick recovery compared to meniscal repair.
Some patients have ongoing discomfort, particularly with degenerative tears and underlying arthritis.
Mild knee swelling for one to two weeks.
Removing meniscal tissue increases the risk of arthritis in the affected compartment. The lateral meniscus is particularly critical for load distribution.
Another area may tear in the future.
Joint infection. Risk approximately 0.3%.
General, spinal, or local anaesthesia.
Weight-bearing immediately. Crutches for comfort for a few days. Return to desk work within days. Driving at one to two weeks. Running at four to six weeks. Return to sport at six to eight weeks.
Review at two weeks. Further follow-up as needed.
The lateral meniscus carries a greater proportion of the load in the lateral compartment. Removing lateral meniscal tissue tends to cause faster arthritis progression than medial meniscectomy. Repair is strongly preferred on the lateral side whenever possible.
Repair is preferred when the tear is in the vascular (outer) zone and the pattern allows it. Tears in the avascular inner zone do not heal with repair.