The epidemiology of hand osteoarthritis

Background Radiographic osteoarthritis most commonly affects joints in the hands, with osteoarthritis at the finger interphalangeal joints (IPJs) thought to be a different subset to that at the first carpometacarpal joint (CMCJ). The thesis aimed to identify risk factors for hand (particularly IPJ) osteoarthritis. Methods Systematic reviews and Delphi studies were performed to identify risk and prognostic factors for incident and progressive IPJ osteoarthritis. A risk prediction model for incident radiographic IPJ osteoarthritis (Kellgren Lawrence (KL) ≥2 in ≥1 IPJ), and a prognostic model for the progression of IPJ osteoarthritis (increase of KL ≥1 in ≥1 IPJ), in the Chingford 1000 Women Study were developed. As the prognostic model performance was poor, the model was revised in the Johnston County Osteoarthritis (JoCo) Project. The burden of hand injury requiring hospital admission, and the association between hand injury and osteoarthritis was investigated in cricketers. Results From the systematic review and Delphi study for incident IPJ osteoarthritis, older age in women, female sex, family history, and injury were important risk factors. Whilst for the progression of IPJ osteoarthritis, older age and family history were important prognostic factors. The prediction model included 459 participants (257 with osteoarthritis at 10 years). Older age, manual occupation, and first CMCJ osteoarthritis were important predictors. The prognostic model included 195 participants (181 progressing at 10 years), with no prognostic factors found to be important. Following revision, female sex was found to be an important factor. Over ten years, 9,188 cricketers presented with hand injuries, most commonly in young adults, with thumb and little finger injuries, particularly fractures and dislocations. Hand injury was associated with osteoarthritis. Conclusion IPJ osteoarthritis might be a continuum of first CMCJ osteoarthritis. Manual occupation and injury could be targeted to decrease disease risk, whilst older age is an unmodifiable risk factor.