Automatic radiographic quantification of hand osteoarthritis; accuracy and sensitivity to change in joint space width in a phantom and cadaver study

This is the final version of the article. Available from Springer Verlag via the DOI in this record.OBJECTIVE: To validate a newly developed quantification method that automatically detects and quantifies the joint space width (JSW) in hand radiographs. Repeatability, accuracy and sensitivity to changes in JSW were determined. The influence of joint location and joint shape on the measurements was tested. METHODS: A mechanical micrometer set-up was developed to define and adjust the true JSW in an acrylic phantom joint and in human cadaver-derived phalangeal joints. Radiographic measurements of the JSW were compared to the true JSW. Repeatability, systematic error (accuracy) and sensitivity (defined as the smallest detectable difference (SDD)) were determined. The influence of joint position on the JSW measurement was assessed by varying the location of the acrylic phantom on the X-ray detector with respect to the X-ray beam and the influence of joint shape was determined by using morphologically different human cadaver joints. RESULTS: The mean systematic error was 0.052 mm in the phantom joint and 0.210 mm in the cadaver experiment. In the phantom experiments, the repeatability was high (SDD = 0.028 mm), but differed slightly between joint locations (p = 0.046), and a change in JSW of 0.037 mm could be detected. Dependent of the joint shape in the cadaver hand, a change in JSW between 0.018 and 0.047 mm could be detected. CONCLUSIONS: The automatic quantification method is sensitive to small changes in JSW. Considering the published data of JSW decline in the normal and osteoarthritic population, the first signs of OA progression with this method can be detected within 1 or 2 years.This work was funded by the Dutch Arthritis Association (Reumafonds). The study sponsor had no involvement in study design, data collection, data analysis, or interpretation of the results

Identification of factors associated with the development of knee osteoarthritis in a young to middle-aged cohort of patients with knee complaints

The objective of this study was to identify risk factors for knee osteoarthritis (OA) development in a young to middle-aged population with sub-acute knee complaints. This, in order to define high risk patients who may benefit from early preventive or future disease modifying therapies. Knee OA development visible on radiographs and MR in 319 patients (mean age 41.5 years) 10 years after sub-acute knee complaints and subjective knee function (KOOS score) was studied. Associations between OA development and age, gender, activity level, BMI, meniscal or anterior cruciate ligament (ACL) lesions, OA in first-degree relatives and radiographic hand OA were determined using multivariable logistic regression analysis. OA on radiographs and MR in the TFC is associated with increased age (OR: 1.10, 95 % 1.04-1.16 and OR: 1.07, 95 % 1.02-1.13). TFC OA on radiographs only is associated with ACL and/or meniscal lesions (OR: 5.01, 95 % 2.14-11.73), presence of hand OA (OR: 4.69, 95 % 1.35-16.32) and higher Tegner activity scores at baseline before the complaints (OR: 1.20, 95 % 1.01-1.43). The presence of OA in the TFC diagnosed only on MRI is associated with a family history of OA (OR: 2.44, 95 % 1.18-5.06) and a higher BMI (OR: 1.13, 95 % 1.04-1.23). OA in the PFC diagnosed on both radiographs and MR is associated with an increased age (OR: 1.06, 95 % 1.02-1.12 and OR: 1.05, 95 % 1.00-1.09). PFC OA diagnosed on radiographs only is associated with a higher BMI (OR: 1.12, 95 % 1.02-1.22). The presence of OA in the PFC diagnosed on MR only is associated with the presence of hand OA (OR: 3.39, 95 % 1.10-10.50). Compared to normal reference values, the study population had significantly lower KOOS scores in the different subscales. These results show that knee OA development in young to middle aged patients with a history of sub-acute knee complaints is associated with the presence of known risk factors for knee OA. OA is already visible on radiographs and MRI after 10 years. These high risk patients may benefit from adequate OA management early in life