CORRELATION OF EXTENT OF MENISCUS LOSS DURING MENISCECTOMY WITH CLINICAL SYMPTOMS, FUNCTION, AND ACTIVITY LEVELS

Abstract

INTRODUCTION: Loss of meniscus tissue leads to decreased clinical function and activity levels. However, no report has quantified the amount of meniscus tissue removed at meniscectomy and correlated meniscus tissue loss with clinical symptoms, function, and activity. We determined, prospectively, the amount of tissue loss at time of partial medial meniscectomy and then correlate extent of meniscus loss with clinical symptoms, function, and activity levels 2 years following the index meniscectomy.

METHODS: In a randomized controlled investigational device clinical trial (Level of Evidence I), 149 patients 18 to 60 years old underwent partial medial meniscectomy and served as controls. There were 81 acute (no prior meniscus surgery) and 68 chronic (1 to 3 prior partial meniscectomies on the involved meniscus) patients. At index surgery, size of the meniscus defect was measured using specially designed instruments, and percent of meniscus loss was calculated based on actual measurements. Patients were followed clinically for a minimum of 2 years after meniscectomy. At each follow-up, every patient completed questionnaires including Lysholm and Tegner scores to assess function and activity. Amount of meniscus tissue at index surgery was correlated with the individual domains of the Lysholm scale. Tegner index was calculated to determine the amount of lost activity regained 2 years after surgical intervention.

RESULTS: Two-year data were available for 127 patients (85% follow-up). There was a significant correlation between the amount of meniscus tissue remaining following the index meniscectomy and 2-year Lysholm domains of squatting (r=0.281, p=0.001), stair-climbing (r=0.251, p=0.004), and swelling (r=0.261, p=0.003). In particular, it is noteworthy that patients who had > 50% of their meniscus remaining had significantly better function than patients who had < 50% meniscus remaining. Patients who had worse or no improvement in pain symptoms at 2 years averaged 42% meniscus remaining, while patients who had improved pain scores had on average 51% meniscus remaining. Tegner index for patients with < 50% meniscus remaining averaged 24%, and for patients with > 50% meniscus remaining averaged 52% (p=0.017); hence, a greater amount of meniscus tissue remaining allowed patients to regain significantly more of their lost activity.

CONCLUSIONS: There is a significant correlation between the amount of meniscus tissue removed at men-iscectomy and clinical symptoms, function, and activity 2 years after surgery. This study confirms the importance of preserving as much meniscus tissue as possible at the time of meniscus repair or meniscectomy as well as the potential positive benefits of regrowing or replacing lost meniscus tissue in order to minimize clinical symptoms that may be suggestive of early degenerative changes.