Computational Dynamic Analysis of Medial Meniscus with Redial Tear, Repair, and Meniscectomy

Purpose

To investigate the influences of radial tears of the medial meniscus and subsequent surgical treatment (repair or meniscectomy) on the knee joint mechanics during normal walking.

Methods

An original multiscale finite element musculoskeletal model was developed to model and study an intact knee model (no RT), four meniscal RT knee models (30% RT, 45% RT, 60% RT, and 90% RT) and 3 treatment option models for 60% RT.

Results

The magnitude and location of peak contact pressure on tibial cartilage were minimally affected (within 0.5 MPa) by the radial tear involving up to 45% of the meniscal rim width throughout the whole gait cycle. The contact area between the femoral cartilage and the medial meniscus continued to decrease as the radial tear degree increased, with peak contact areas of approximately 450 mm², 435 mm², 430 mm², and 405 mm² for 30%, 45%, 60%, and 90% RT. Regarding the surgical treatment, meniscectomy led to the most significant increase in the contact pressure and alterations in the kinematics, while suture repair restored the contact stress to the level of the intact knee joint and a better recovery in the contact area. An optimized partial meniscectomy could reduce loading on the meniscus and joint cartilage, but no significant improvement in contact area compared with 60% RT.

Conclusion

Meniscal tear and its resultant partial meniscectomy have a positive impact on the maintenance of high levels of contact stresses, whereas meniscectomy causes the highest risk for the development of knee osteoarthritis. Meniscal repair procedures significantly restore native meniscal function.