Background: Functional limitations exist postmeniscectomy, but preoperative data are scarce.
Purpose: To examine knee function, knee muscle strength and performance in middle-aged patients with degenerative meniscal tears, eligible for arthroscopic partial meniscectomy.
Study design: Cross-sectional study.
Methods: Eighty-two participants with MRI verified degenerative meniscal tear (35% women, mean age 49 years) answered the Knee injury and Osteoarthritis Outcome Score (KOOS) and were tested for isokinetic knee muscle strength and lower extremity performance (one-leg hop for distance, 6 m timed hop and maximum number of knee-bends in 30 s). Limb Symmetry Index (LSI) was used to express side-to-side differences in per cent using the non-injured leg as the control. An LSI ≥90% was considered normal.
Results: Mean scores of the five subscales of the KOOS were from 13 to 36 points lower compared with a population-based reference group and similar to patients prior to anterior cruciate ligament reconstruction. Quadriceps strength and lower-extremity performance were impaired for the injured leg compared with the non-injured leg (p<0.001), with a mean difference of 13% in quadriceps strength and between 8% and 13% in lower-extremity performance. Between 41% and 52% of the participants had abnormal LSI values in quadriceps muscle strength and lower-extremity performance.
Conclusion: Middle-aged patients with a symptomatic degenerative meniscal tear experience functional knee problems when eligible for meniscectomy. Included participants reported difficulty with knee pain, symptoms, function and quality of life and quadriceps strength and lower-extremity performance were impaired. Approximately 50% of the study group had clinically relevant impairments in quadriceps strength and lower-extremity performance, defined as >10% differences between the injured and the non-injured leg.
Keywords: Knee injuries; Miniscal pathology; Muscle imbalance; Strength isometric isokinetic.