JOINT DEGENERATION
When indicated in the treatment of acute meniscal tear, surgery should preserve as much functional meniscal tissue as possible to mitigate patient risk for osteoarthritis.

Rationale

One high quality (Hede, 1986) and eleven low quality (Andersson-Molina, 2002; Cohen, 2012; Englund, 2003; Englund, 2004; Englund, 2009; Hulet, 2001; Rockborn, 1995; Roos, 1998; Roos, 2008; Stein, 2010,;Zhang, 2018) articles evaluating joint degeneration after meniscal tear were reviewed. Several studies indicate that meniscal tear is associated with a greater risk of degenerative changes in joint tissues indicative of knee osteoarthritis compared to uninjured knees/intact menisci (Englund, 2009). Additionally, meniscectomy is associated with a greater prevalence of degenerative changes compared to conservative treatment/no meniscectomy (Cohen, 2012; Englund, 2003; Roos, 1998; Hulet, 2001). While partial meniscectomy is associated with a lesser prevalence of degenerative changes compared to total (Andersson-Molina, 2002; Englund, 2004) and subtotal (Rockborn, 1995) meniscectomy, partial meniscectomy also results in a higher prevalence of degenerative changes compared to meniscal repair (Stein, 2010).

The primary limitation of this body of evidence is that the majority of studies were retrospective in nature. Surgical decision making should be based on the clinical scenario (e.g. the extent, type and location of the initial meniscal trauma), thus there are ethical implications that limit the ability to conduct randomized clinical trials in meniscus patients. Therefore, while there is a preponderance of evidence indicating that meniscal tears in general and surgical removal of a larger amount of meniscal tissue are associated with a greater risk of joint degeneration, the supporting evidence is inherently limited by the nature of the investigations. Additionally, these studies generally did not distinguish the potential influences of the location, type, or extent of the meniscal injury on clinical and radiographic outcomes, thus generalizability of the findings to specific meniscal cases is limited.

Benefits/Harms of Implementation
The primary risk of meniscal preservation, specifically meniscus repair, is the higher rate of subsequent surgery as compared to meniscal debridement or meniscectomy, as well as the added cost of and rehabilitation/recovery following the procedure. However, the long-term value of meniscal preservation to delay or prevent advancement of chondral degeneration should be considered.

Outcome Importance
Meniscal preservation has the potential to delay or prevent joint degeneration which minimizes resulting long term disability.

Cost Effectiveness/Resource Utilization
Meniscal repair techniques, use of implants and additional operative time is expected with meniscal preservation techniques, particularly for meniscus repair. There is some evidence that this approach is cost effective over time (Deviandri, 2023).

Acceptability
Meniscus preservation techniques including meniscus repair are readily accepted and accessible.

Feasibility
There are no concerns regarding the feasibility of meniscal preservation techniques for acute meniscal pathology.

Future Research
The optimal indications and techniques for meniscal preservation techniques, specifically meniscal repair, deserve further investigation, particularly in regards to which types of tears are particularly amenable to repair. Longer term follow-up including assessment of joint degeneration with imaging as well as clinical outcomes and subsequent surgery such as knee arthroplasty is needed.