Knee Meniscal Injuries

April 26, 2024

Let’s delve into knee meniscal injuries!

The prevalence of knee meniscal injuries has risen over the years, possibly due to increased sports participation and advancements in imaging technology that aid in better identification of these injuries (Chambers and Chambers, 2019). Advances in orthopaedic research have revolutionised the management of meniscal tears. Total meniscectomy, once common, has given way to meniscus preservation surgery, recognising the meniscus’s role in knee biomechanics.

The meniscus plays a crucial role in the knee joint, with anatomical, biomechanical, and functional significance (Makris et al., 2011). It is believed that individuals with known meniscal injuries experience accelerated cartilage degeneration, leading to an early onset of osteoarthritis (Jarraya et al., 2017). Knee meniscal injuries are among the most common sports-related injuries, highlighting the growing importance of improving the diagnosis and treatment of such injuries (Bhan, 2020).

The treatment of meniscal tears depends on several factors including age, tear location, and type, influence treatment decisions. Determining the tear’s location plays a crucial role in determining the most effective management approach. The meniscus receives varying blood supply across different areas, with higher blood supply correlating to better healing potential. The meniscus is divided into three zones based on vascularity:

• Red zone: the outer edge of the meniscus with sufficient blood supply.
• Red-White zone: the middle section with reduced blood flow.
• White zone: the innermost part with minimal vascularity.

Conservative management is advocated in tears in the red zones or with a high blood supply, even better results are seen with stable tears which are small than 5mm in length in this zone. Meniscal tears are also categorized by thickness. A tear is classified as complete if it extends through the entire meniscus; if it remains attached, it is deemed incomplete. Complete tears are further classified as stable or unstable. A stable tear remains in place and has a higher chance of healing naturally, while unstable tears lead to abnormal meniscus movement and often require surgical intervention.

Surgical treatment is the core treatment for other tears. In the past 40 to 50 years, the management of meniscal injuries, especially surgical approaches, has evolved based on advancements in orthopaedic research. Prior to the 1970s, the standard practice for managing meniscal tears was a total meniscectomy. This was based on the then believed knowledge that the meniscus served no function within the knee joint. However, when individuals were reviewed after their total meniscectomy there were anatomical changes within the knee indicated a predisposition to early degenerative changes (Fairbank, 1948). It was then suggested that the meniscus is important in weight bearing function and without it the biomechanics of the knee is affected predisposing an individual to early degenerative changes in the knee.

While partial meniscectomies are the most common orthopaedic surgery worldwide, studies have shown that a partial meniscectomy does not yield better results than a placebo or sham surgery. Clinical guidelines are increasingly advising against this procedure, shifting towards the concept of preserving the meniscus through meniscal repairs. The goal of meniscal repair is to promote healing while avoiding the negative effects of partial or full meniscectomies. Short-term results have been promising, with a low failure rate of less than 10% after 2 years (Lee, 2005). However, the long-term effects of meniscal repair have been less positive, with a failure rate of up to 30% after 5 years (Nepple at al., 2012).

There are other treatments including meniscal allografting, meniscal scaffolds and partial meniscal substitute but these procedures are more complex and less common the complete.

Conservative management can include Physiotherapy in the form or rehabilitation or Ostenil Injections.

Call Physiotherapy Matters on 0191 285 8701 for a free 15 mins triage call to see if Physiotherapy can help your meniscal / knee injury.

References

Bhan, K., 2020. Meniscal tears: current understanding, diagnosis, and management. Cureus, 12(6).

Chambers, H.G. and Chambers, R.C., 2019. The natural history of meniscus tears. Journal of Pediatric Orthopaedics, 39, pp.S53-S55.

Fairbank, T.J., 1948. Knee joint changes after meniscectomy. The Journal of Bone & Joint Surgery British Volume, 30(4), pp.664-670.

Jarraya, M., Roemer, F.W., Englund, M., Crema, M.D., Gale, H.I., Hayashi, D., Katz, J.N. and Guermazi, A., 2017, April. Meniscus morphology: does tear type matter? A narrative review with focus on relevance for osteoarthritis research. In Seminars in arthritis and rheumatism (Vol. 46, No. 5, pp. 552-561). WB Saunders.

Lee, G.P. and Diduch, D.R., 2005. Deteriorating outcomes after meniscal repair using the Meniscus Arrow in knees undergoing concurrent anterior cruciate ligament reconstruction: increased failure rate with long-term follow-up. The American Journal of Sports Medicine, 33(8), pp.1138-1141.

Makris, E.A., Hadidi, P. and Athanasiou, K.A., 2011. The knee meniscus: structure–function, pathophysiology, current repair techniques, and prospects for regeneration. Biomaterials, 32(30), pp.7411-7431.

Nepple, J.J., Dunn, W.R. and Wright, R.W., 2012. Meniscal repair outcomes at greater than five years: a systematic literature review and meta-analysis. JBJS, 94(24), pp.2222-2227.