Sports injury, occupational physical activity, joint laxity, and meniscal damage.

OBJECTIVE To investigate the risk factors for meniscal damage, an important determinant of knee osteoarthritis. METHODS We studied 243 men and women aged 20-59 years in whom the diagnosis of a meniscal tear was confirmed for the first time at arthroscopy, over a 25 month period, in 2 British hospitals. Each case was compared with one or 2 community controls, matched by age and sex, who were registered with the same general practitioner. Information on exposure to risk factors was obtained by a structured questionnaire and physical examination. RESULTS Meniscal tear was strongly associated with participation in sports during the 12 months preceding the onset of symptoms; the risk was particularly high for soccer (OR 3.7; 95% CI 2.1-6.6). Higher body mass index and occupational kneeling (OR 3.8; 95% CI 1.3-11.0) and squatting (OR 2.9; 95% CI 1.0-8.0) were associated with an increased risk of degenerative meniscal lesions, after adjustment for social class, joint laxity, and sports participation. Joint laxity was associated with degenerative meniscal lesions independently of occupational physical activity, sports, and obesity. CONCLUSION Our results confirm the importance of sporting activities entailing knee torsion in acute meniscal tear. They also point to a role for occupational activity, adiposity, and joint laxity in the pathogenesis of degenerative meniscal lesions. Modifying these mechanical risk factors may serve to reduce the risk of meniscal injury and may also help to prevent later knee osteoarthritis.