Objective To investigate the methods and effectiveness of surgical treatment for posteromedial corner (PMC) injury combined with anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) ruptures. Methods Between February 2009 and February 2012, 15 patients (15 knees) with PMC injury combined with ACL and PCL ruptures underwent PMC repair with suture anchor and ACL and PCL reconstruction. There were 7 males and 8 females with an average age of 39 years (range, 15-59 years). The causes of injury were traffic accident injury in 6 cases, sport injury in 7 cases, and sprain injury in 2 cases. The disease duration was 3-15 days with an average of 7 days. All patients presented positive results of anterior drawer test, posterior drawer test and valgus stress test, and dysfunction of knee joint. Of 15 cases, 3 had ACL and PCL ruptures, 5 had ACL rupture, 3 had ACL injury at the attachment point of the condyles crest, and 4 had PCL rupture; 9 had PMC tear at the femur insertion, 5 had PMC tear at the tibia insertion, and 1 had PMC tear in the body area. Results All incisions healed by first intention with no complication of infection or stiffness of knee. All cases were followed up 18.4 months on average (range, 10-36 months). At last follow-up, 14 cases had normal knee flexion and extension ranges, but 1 case had 10° limitation of the knee extension. Except 1 case which had weakly positive valgus stress test, the other patients showed negative results of anterior drawer test, posterior drawer test, and valgus stress test. Based on the improved Lysholm classification standard, the results were excellent in 8 cases, good in 5 cases, and fair in 2 cases; the excellent and good rate was 86.7%. Conclusion Early repair of the PMC and reasonable reconstruction of cruciate ligament can effectively restore the knee stability for patients with PMC injury combined with ACL and PCL ruptures.
Objective To review the recent anatomy and biomechanical research progress of knee posteromedial corner, to analyze deficient aspect, and to predict future research directions. Methods Domestic and international l iterature about the anatomy and function of knee posteromedial corner in recent years was reviewed extensively, at the same time, the biomechanics of corresponding structure was summarized and analyzed. Results The anatomical structures ofknee posteromedial corner included the static stabil ity structures and the dynamic stabil ity structures. The dynamic stabil ity structures were more important, including posterior root of medial meniscus, posterior obl ique l igament, semimembranosus extensions, meniscotibial l igament and obl ique popl iteal l igament. The posterior obl ique l igament was most important structure to contribute to stabil ization of valgus, anterior internal rotation of knee and posterior movement of tibia. Conclusion Anatomical reconstruction of knee posteromedial corner especially the posterior obl ique l igament is the key to the reconstruction of knee posteromedial function stabil ity.