Osteoarthritis of the hip and knee in former male professional soccer players

Professional soccer (PS) players are at great risk of osteoarthritis (OA) of the knee and hip. Following the PRISMA guidelines, the key words 'osteoarthritis' and 'soccer' or 'football' were matched with 'players' or 'former' or 'retired' and with 'hip' or 'knee' on December 24, 2017 in the following databases: PubMed, Cochrane, Google scholar, Embase and Ovid. Only comparative studies reporting the prevalence rate of OA of both hip and knee joint in former PS athletes (fPSa) and age and sex matched controls were considered. In fPSa, the prevalence rate of OA of both hip and knee is significantly higher compared to age and sex matched controls. The pathological pathways responsible for the development of OA of the hip and knee in PS athletes (PSa) are still not clearly understood. The prevalence rate of clinical OA of the hip was 8.6% in fPSa and 5.6% in controls (odd ratio (OR) = 1.5; 95% CI: 1.06-2.31). The radiographic rate of OA was 21.2% in fPSa and 9.8% in controls (OR = 2.4; 95% CI: 1.66-3.69). A total of 14.6 and 53.7% of fPSa presented clinical and radiographic signs of OA of the knee, respectively, vs 12.9% (OR = 1.16; 95% CI: 0.86-1.55) and 31.9% (OR = 2.47; 95% CI: 2.03-3.00) of controls. Sonographic evidence of OA of the knee was found in 52% of fPSa and 33% of controls (OR = 2.2; 95% CI: 1.24-3.89). Preventive training programmes should be developed to reduce the number of fPSa presenting early OA.