The Oxford unicompartmental knee prosthesis: a 2-14 year follow-up.

Our medium- and long-term results obtained with the Oxford unicompartmental knee prosthesis for unicompartmental knee osteoarthrosis are presented. Ninety-seven prostheses were evaluated (87 medial, 10 lateral) in 86 patients, with the Hospital for Special Surgery knee score after 2-14 years (mean follow-up: 6 years 9 months). Five prostheses were lost to follow-up. Eight patients died, not related to surgery; none had undergone a revision. Fourteen revisions (of which one bilateral UKP), 11 medial and three lateral, were performed. The mean HSS score of the 69 UKPs was 178.8 (80% excellent, 10% good, 4% fair, 6% poor). These findings confirm the good results reported in other studies, regarding proper patient selection and a consistent operative technique.

Repair of chronic ruptures of the anterior cruciate ligament using allograft reconstruction and a ligament augmentation device.

A prospective study was performed to determine the effect of a ligament augmentation device (LAD) on the replacement of the anterior cruciate ligament (ACL) using tendon allografts. Twenty-five patients were followed for 66 to 98 months after tendon allograft replacement with LAD reinforcement for ACL rupture. The evaluation was done using the form of the International Knee Documentation Committee (IKDC), the Lysholm score and the Tegner scale. Two patients sustained a rerupture after major injury. Three other multiply-injured patients scored poorly because of associated injuries and fractures (IKDC grade D). Four patients scored normal (grade A), 12 patients nearly normal (grade B), and 5 patients abnormal (grade C). The Lysholm score showed 14 excellent (average 96), 5 good (average 86) and 4 fair results (average 76). Three patients with excellent results were IKDC grade C, solely because the xrays showed slight narrowing of the medial joint line, which might indeed indicate future problems. On the Tegner scale, the sports level decreased by an average of 1.4 points (from 7.25 to 5.83). Only five patients showed an anteroposterior displacement of more than 3 mm, of which only one was in the grade C group.

The Oxford unicompartmental knee prosthesis: a 5-year follow-up.

We present our medium-term results with the Oxford unicompartmental knee prosthesis for unicompartmental osteoarthrosis. After an average of 58 months the mean on the Hospital for Special Surgery knee score in 38 medial and 3 lateral prostheses (39 patients) was 87. There were three revisions; in the remaining 36 patients the results were: 29 excellent, 3 good, 2 moderate, and 2 poor. In two of the three revisions and in two of the four poor and moderate results, the indications for the procedure were debatable. Our findings confirm the good results reported in other studies and underline the importance of adhering to strict indications to reduce the number of poor results.

Long-term results of tendon allografts for anterior cruciate ligament replacement in revision surgery and in cases of combined complex injuries.

We assessed the long-term validity of anterior cruciate ligament (ACL) reconstruction using tendon allografts. Nineteen patients were followed up for 8 years (mean 94 months) after tendon allograft replacement for ACL rupture. The evaluation used the International Knee Documentation Committee (IKDC) grades, the Lysholm score, and the Tegner scale. Two patients sustained a rerupture after a serious injury. Two others scored poorly because of associated proximal ipsilateral tibial and other fractures (IKDC grade D). Nine patients scored nearly normal (grade B) and six abnormal (grade C). The Lysholm score showed nine excellent (average 98), five good (average 87), and one fair result (70). Two of the excellent-rated patients were IKDC grade C solely because the X-rays showed a slight (1-mm) narrowing of the medial cartilage. One patient had 0.5-mm narrowing. The X-ray findings may indeed indicate future problems. On the Tegner scale the sports level decreased by an average of 2.1 points (from 6.87 to 4.73), and by 0.8 point compared to the level at which the patient had wished to perform. ACL repair using tendon allografts appears to provide satisfactory results on the Lysholm and Tegner scales. The IKDC scoring suggests future cartilage degeneration. Its value for knees with multiple ligament lesions and for revision cases is demonstrated. Only two reruptures were noted, suggesting good reliability of allografts on the long term.

Prosthetic versus tendon allograft replacement of ACL-deficient knees.

ACL reconstruction is still controversial. Between November 1985 and October 1987, 57 ACL reconstructions were performed using a Dacron graft. Evaluation was done using the Lysholm rating system and Tegner scale. The Lysholm score averaged 84.2. Regarding the level of performance, the patients had lost an average of 2.1 points on the Tegner scale. 18 of the 57 patients developed a synovitis. In 11 patients (19 per cent) the implant had to be removed. CT scan of the operated knee proved the Dacron graft to be nonfunctioning in as many as 40 per cent of the patients. Because of this high complication rate, the authors started to use deep-frozen (-70 degrees C) tendon allograft material. Both Achilles and Tibialis Posterior tendons were implanted using the over-the-top technique with or without an additional extra-articular procedure. Complications as seen with the rigid synthetic ligaments were absent. The preliminary results seem satisfactory in that the functional demands placed on the knee are not restricted.