Investigating the utility of HR-pQCT for the assessment of joint space and bone mineral density in hand osteoarthritis

Objective Osteoarthritis affects joints of the hand and is radiographically characterized by joint space narrowing and changes in volumetric bone mineral density (vBMD). High-resolution peripheral computed tomography (HR-pQCT) allows for three-dimensional analysis of joint space width (JSW) changes but has yet to be applied to hand OA (HOA). The purpose of this study was to assess the utility of HR-pQCT in quantifying JSW and vBMD changes in HOA. Design The 2nd and 3rd distal interphalangeal (DIP2, DIP3) and trapeziometacarpal (TMC) joints of 20 women (10 controls, 10 HOA) were scanned using HR-pQCT. The Diseases of the Arm, Shoulder, and Hand (DASH) questionnaire and the Jebsen Hand Function Test (JHFT) were obtained. Radiographs were scored using the Eaton-Littler classification. We assessed between-group differences in HR-pQCT outcomes, and relationships between HR-pQCT outcomes and patient and radiographic characteristics. Results JSW maximum (JSW.Max) was higher in OA patients in the DIP2 (OA median [interquartile rage]: 2.07 mm [1.90–2.18], controls: 1.88 mm [1.84–1.89]) and DIP3 joints (OA: 2.01 mm [1.89–2.24], controls: 1.86 mm [1.82–1.95]). DIP3 JS volume was higher in OA (30.36 mm3, 19.35–34.57 mm3, controls: 17.05 mm3, 15.53–18.52 mm3). DASH scores were positively associated with DIP2 JSW asymmetry (JSW.AS), and JHFT times were positively associated with DIP3 JSW.Max, JSW.AS, and proximal DIP2 vBMD. Worsening radiographic TMC OA was associated with first metacarpal vBMD, JSW minimum, JSW.Max, and JSW.AS. Conclusions These preliminary findings suggest that HR-pQCT may be useful in investigating JS changes in HOA and warrants further investigation.