Knee function, Physical Activity and Perceived Health after Meniscectomy in the Middle-aged

Abstract: The aim of this thesis was to explore the impact of meniscal injury and meniscectomy on joint and muscle function, physical activity and perceived health in middle-age subjects and to evaluate the effect of a functional exercise program. Male and female post meniscectomy patients participated in Studies I-IV (n=45 in Studies I-III, n=99 in Study IV) and Study IV also included 94 controls. Outcome measures were thigh muscle strength, functional performance tests, femoral cartilage quality (assessed by dGEMRIC) and Body Mass Index (BMI) in addition to four questionnaires: the Knee Injury and Osteoarthritis Outcome Score (KOOS), the Knee Self Efficacy Scale (K-SESABC), the Physical Activity Scale (PAS) and the MOS Short Form-36 (SF-36) health scale. Studies I-II revealed that patients had less strength in the operated compared to the nonoperated leg (mean difference 9%) and the deficit was associated with symptoms and functional limitations (KOOS). Cartilage quality (dGEMRIC Index) in the medial compartment was 14% lower than in the lateral, and correlated positively with thigh muscle strength/BW and negatively with BMI. In study III, patients were randomized to a four- month functional exercise intervention or to no intervention. The exercise group tolerated the training well and improved in one-leg hop, hamstrings strength and quadriceps endurance. In study IV patients scored lower than controls in K-SES and in two SF-36 subscales. Only 46% of the patients had resumed their pre-injury PA level, although current PA did not differ between the groups. In the patient group, K-SES was associated with PAS (rs=0.42) and SF-36 (rs= 0.35-0.85). Female patients scored lower than male patients in K-SES and four SF-36 subscales. In conclusion, patients were found to have considerable symptoms, functional limitations and lower self efficacy than controls 3-4 years after meniscectomy. Strong thigh muscles seem to be helpful for improving knee function and protecting knee cartilage, whereas high BMI appears to be harmful to the cartilage. Functional exercise training after meniscectomy could be a useful method for restoring knee function, thus helping patients to resume PA and maintain good health.