Purpose of the study: This prospective anatomic study was conducted to analyze meniscal healing after arthroscopic repair.
Material and method: Two preliminary studies (a radio-anatomic study and a comparative arthroscan-arthros-copy study) were conducted to define strict radiological criteria (contiguous slices or spiral acquisition)which could be interpreted by all observers. Sixty-five vertical meniscal lesions were included in the study and divided into four groups according to localization (medial or lateral) and knee stability (stable or associated ligamentoplasty). Arthroscopic repair was performed in all cases. Mean length of the lesions was 20.31±6 mm. Minimum follow-up was six months. The work-up included an arthroscan and the IKDC function score.
Results: The work-up could be interpreted for 62 knees. The overall outcome according to Henning was: 42% complete healing, 31% incomplete, 27% failure. Healing outcome was similar for lesion in a red-red zone (73%) or a red-white zone (70%). The healing surface could be assess for 43 knees: 37% complete healing, 21% partial healing of more than half of the initial tear, 12% partial healing of less than half of the tear, and 12% failure. The analytic results of 17 medial repairs on stable knees yielded: 9 complete, 2 partial, 4 failure, with IKDC (79, 68, 73 points) having no significant influence. For the 24 medial repairs on unstable knees outcome was: complete healing in 10, partial in 6 and a good IKDC score (80.85 points). Functional outcome was poor for the eight failures (67 points). Lateral repairs on 11 stable knees yielded: complete healing in 2 (IKDC 76 points), partial in four (IKDC 94 points) and failure in five (IKDC 82 points). For the ten unstable knees, complete healing was achieved in five and partial healing in five with good patient satisfaction (IKDC 80.70 points).
Conclusion: Methodologically, arthroscan provided a good assessment of healing. The notion of the healing surface appears to be more appropriate than thickness, since partial healing can transform an unstable knee into a stable one. Clinically, in one third of the knees, meniscal healing could not be achieved. This failure was more frequent and less well tolerated for the medial lesions. For the lateral lesions, incomplete healing was more frequent, perhaps in relation to meniscal mobility and the associated ligamentoplasty which apparently protected the meniscal repair. In this series, meniscal healing did not have a significant influence on the functional outcome.