Post operative approaches to a meniscal repair or partial meniscectomy are fairly well established and come with high success rates.
However, within the Canadian healthcare system, the wait times for those surgeries are long and development of co-morbidity is common. This wait may be compounded if the initial treating/assessing professional is not quick to identify those who will require surgery vs those who will respond to conservative management.
Early identification may avoid having those who are capable of conservative rehabilitation filling the schedules of surgeons, thus opening the space for those unlikely to respond without the surgical approach.
The function of a meniscus:
- Load transmission
- Increase joint contact area
- Contribute to joint stability
Prevention of soft tissue impingement
It is because of the above list that preservation of the whole meniscus is so crucial.
It is well known that much of the meniscal tissue is not vascular. The lateral meniscus is only vascular in the outer 10-25% and the medial in the outer 10-30%. The inner avascular portions of each meniscus derive nutrition from the synovial fluid through cyclical compression/decompression, ie movement.
Without a direct blood supply can the meniscus heal on it’s own?
The answer to this question should help us better choose those clients who are likely to respond solely to conservative management.
Pujol and Beaufils (2009) reviewed the literature on this question using a total of 10 different studies to come to their conclusions. The population studied were those with meniscal tears left in situ when repairing a torn ACL.
The majority of the tears in the study were located at least in part in the vascular portion of the meniscus.
Surprisingly, pain or mechanical symptoms related to the medial tibiofemoral joint were only reported in 0-66% of the cases with arthoscopically confirmed tears. Complete healing was found in 50-61% of cases. In 1-50%, the tear remained unhealed or had extended, 10-66% (mean 14.8%) complained of residual pain or had subsequent surgery.
Pain or mechanical symptoms were only reported in 0-18% of cases with confirmed tears. Complete healing was found in 55-75% of cases. The tear was unhealed or extended in 1-22.5% of cases. Residual pain or subsequent surgery was reported in 0-22% (mean 4.8%).
There appears to be a higher failure rate for conservative treatment of medial meniscal tears, with the lateral having 3 times better results. It is recommended to consider surgical referral early with unstable tears and those in which the blocked range of motion is irreducible. Further, those with a medial tear that is painful on initial exam are more likely to require referral. The stable lateral tear irrespective of pain on initial exam has the best chance for conservative management.
All persons with meniscal tears of all types should be consulting a health professional and be participating in an active rehabilitation program. The goal may differ depending on the tear. It may be “prehabilitation” to prepare for successful surgery and prevention of co-morbidity related to the injury or it may be full resolution and return to activity.
Pujol N, Beaufils P. Healing results of meniscal tears left in situ during anterior cruciate ligament reconstruction: a review of clinical studies. Knee Surg Sports Traumatol Arthrosc. (2009)17:396-401
Yagishita K, Muneta T, Ogiuchi T, Ichiro S, Shinomiya K. Healing potential of meniscal tears without repair in knees with anterior cruciate ligament reconstruction. Amer J Sports Med (2004)32:1953-1961