Risk factors for joint replacement in knee osteoarthritis; a 15-year follow-up study

During osteoarthritis (OA), the knee is the most commonly affected joint with an estimated prevalence of 15%. Conventional radiography is the most frequently used modality for imaging of knee OA although the radiographic changes in knee OA are not well correlated with symptoms. Therefore in this study, the author revealed the radiographic findings including joint space narrowing and MRI detected bone marrow lesions, synovitis and effusion were all significantly associated with the long-term risk of TKA in persons with knee osteoarthritis.    

To assess whether MRI, radiographic, or clinical findings are correlated with long-term risk for total knee arthroplasty (TKA) among subjects with knee osteoarthritis (KOA).

A follow-up of 100 KOA patients who engaged in a clinical trial from 2000 to 2002 was conducted. All patients were estimated for radiography and MRI as well as clinical data of the inclusion knee. Danish National Patient Register was used to collect data on TKA procedures. Radiographic, MRI and clinical findings were examined for connections with consequent TKA.

A total of 66% obtained a TKA in target knee, and 37% obtained TKA in another knee during the mean follow-up of 15 years. The degree of joint space narrowing can be defined as a radiological sum score that comprises osteophytes, subchondral sclerosis and cysts. It was found to be associated with subsequent TKA. MRI identified effusion, synovitis, and bone marrow lesions were likewise correlated with following TKA with an adjusted OR of 9.1, 2.8, and 2.3, respectively. The subsequent TKA showed a relationship with the enhanced BMI of another knee but not with the target knee.  

Radiographic findings comprising MRI and joint space narrowing identified effusion, synovitis, and bone marrow lesions were all remarkably correlated with the long-term risk of TKA among individuals with KOA.