Abstract
Purpose: The collagen meniscus implant (CMI, Sulzer) is a meniscal substitute with a collagen matrix serving as a tutor for autologous regeneration of meniscal tissue. The goal is to prevent mid-term degradation after meniscectomy. The CMI is inserted arthroscopically. The purpose of this multicentric European study was to verify the safety, technical feasibility, and short-term clinical efficacy of the CMI in a population of patients undergoing medial meniscectomy. The long-term results should be obtained within a delay of five years at least.
Material and results: The series included patients with medial meniscus lesions alone, with or without lesions of the anterior cruciate ligament (present in 44% of the patients and repaired at the same time). Patient consent was obtained in all cases (in France in accordance with the Huriet law). Patients with lesions of the lateral ligament, associated trade IV cartilage lesions, or lesions of the posterior cruciate ligament were excluded. The study included 98 patients, mean age 33 years. Four patients were excluded from the analysis due to complications. Currently, 66 patients are available for evaluation one year after insertion of the CMI. Subjective outcome, the Lysholm score, and x-ray and MRI findings were recorded. Evaluation up to five years follow-up is scheduled.
Results: Complications: There were four early complications: infectious arthritis (n=1), puriform arthritis without germ (n=2), implant rupture (n=1). There were no implant-related postop complications.
Clinical results: At one year follow-up, the Lysholm score was 97. Pain was mild (1 on the visual analogue scale) and was only observed in one out of six patients: 87% of the patients had a normal or nearly normal knee.
Radiological results: There were no radiological signs of early degeneration. It was difficult to interpret the MRI results which visualised a structure with an intermediary signal in the form of a meniscal triangle. MRI did on show any sign of deleterious effect on the neighbouring cartilage.
Discussion: This technique for replacing the meniscus is an alternative to allogenic grafting. These preliminary results must of course be interpreted with caution. They show that arthroscoic implantation of the CMI is feasible but difficult. There was no evidence of an immunological reaction. Complications were related to the operative difficulty. Clinical results were satisfactory at one year, particularly in terms of pain. On the other hand, the biomechanical value of the implant cannot be assessed until longer follow-up data becomes available.
Conclusion: In light of the operative difficulty, the long postoperative recovery due to the rehabilitation protocol, the CMI should be used for symptomatic knees after meniscectomy, particularly in case of anterior laxity.
The abstracts were prepared by Docteur Jean Barthas. Correspondence should be addressed to him at Secrétariat de la Société S.O.F.C.O.T., 56 rue Boissonade, 75014 Paris.
