Non-operative treatment of complete tears of the medial collateral ligament of the knee.

A prospective study was designed to compare the results of operative and non-operative treatment of complete (Grade-Ill) isolated tears of the medial collateral ligament of the knee. For eighteen consecutive months, all patients suspected of having this injury were examined under anesthesia and arthroscopically before primary surgical repair was performed. At the time of surgery, the preoperative diagnosis was confirmed in all knees. Surgery was followed by a six-week period of immobilization of the knee in a plaster cast and a well defined, supervised rehabihitation program. These patients comprised Group I. For the ensuing eighteen months, all patients with this injury of the medial collateral ligament were also exammed under anesthesia and by arthroscopy but were treated by immobilization of the knee in a plaster cast for two weeks, the use of a cast-brace for four weeks, and the same rehabilitation program as was used in Group I. These patients comprised Group II. Sixteen patients in Group I were followed for an average of 3.1 years and twenty patients in Group II, for an average of 2.4 years. In both groups, examination under anesthesia and arthroscopic evaluation of the intraarticular structures demonstrated that there was no structural damage to the anterior cruciate ligament, menisci, or articular surfaces. Fifteen of the sixteen patients in Group I and seventeen of the twenty patients in Group II had a good or excellent result. The results seem to indicate that primary surgical repair of a complete (Grade-HI) isolated tear of the medial collateral ligament is not necessarily indicated. Rehabilitation was expedited in the patients who were treated with cast-bracing alone, since these patients regained their strength, as measured by the Cybex-il machine, in significantly (p < 0.001) less time (Group I, 14.9 ± 1.5 weeks and Group II, 11.3 ± 1.8 weeks) . The key to success in the treatment of this injury is to establish that there is an isolated lesion with no associated damage to other vital structures, particularly the anterior cruciate ligament and the menisci. It has been well documented in the orthopaedic hiterature, in both laboratory and clinical studies, that predictably good or excellent results can be obtained by primary : Department of Orthopaedics, College of Medicine, University of Florida, Box J-246, JHM Health Center, Gainesville, Florida 32610. repair when the medial collateral ligament is completely torn. In 1938, Palmer described the results after primary repair. Over the past thirty years, O’Donoghue has advocated surgical intervention for all complete tears of the medial collateral ligament13’7. Godshahl and Hansen, in 1974, recommended primary surgical repair whenever the valgus stress test on an injured knee produces a relative increase in the width of the medial joint space of four millimeters or more. Many other investigators also reported consistently good to excellent results following primary repair of a completely torn medial collateral higament’’4’7”#{176}19. On the other hand there have been other, less well known reports that described non-operative approaches in the treatment of this lesion. In 1946, Richman and Barnes used a closed method of treatment for significant damage to the knee ligaments of parachutists. Of the eighty-five patients whose cases they reviewed, the vast majority (95 per cent) had an excellent result after six to ten weeks of immobilization in a plaster cast with the knee in 30 degrees of flexion. In 1974, Ellsasser et al. listed strict criteria for the non-operative management of injuries of the collateral ligaments, which when carefully followed gave a success rate of 98 per cent. More recently, Fetto and Marshall described a rationale for treating these injuries. In a retrospective study of twenty-one patients with an isolated tear of the medial collateral ligament, they found that ‘ ‘isolated Grade III [complete] MCL injuries did equally well under non-operative as operative treatment”. O’Connor described certain indications for non-operative treatment of complete tears l , including the presence of an infected turf burn or a severe upper-respiratory infection that precluded surgery. Under these circumstances, he recommended that patients be treated with immobilization of the knee in a plaster cast for at least four weeks. Previous laboratory studies have provided some support for this non-operative approach. Jack produced cornplete tears of the medial collateral ligament in cats by forceful abduction of the knee over the edge of an operating table. The presence of a complete tear was confirmed surgically, and in some animals displacement of the torn ends was allowed to remain. Even though no immobihization was used, healing occurred provided the ends of the torn ligament were not widely separated. Clayton and Weir compared the results in repaired and unrepaired tears of the medial collateral ligament in dogs. Although the reLIG. MEDIAL CAPSULAR