To validate the precision of digitally reconstructed radiograph (DRR) radiostereometric analysis (RSA) and the model-based method (MBM) RSA with respect to benchmark marker-based (MM) RSA for evaluation of kinematics in the native hip joint. Seven human cadaveric hemipelves were CT scanned and bone models were segmented. Tantalum beads were placed in the pelvis and proximal femoral bone. RSA recordings of the hips were performed during flexion, adduction and internal rotation. Stereoradiographic recordings were all analyzed with DRR, MBM and MM. Migration results for the MBM and DRR with respect to MM were compared. Precision was assessed as systematic bias (mean difference) and random variation (Pitman’s test for equal variance).Objectives
Methods
Twenty four patients who had a Proximal Row Carpectomy (PRC) were reviewed 9 months to 9 years post surgery (average 5 yrs). The initial cohort of 14 patients was previously reported to the society in a review encompassing 12 months to five years follow-up post surgery. No patients were lost to follow-up. Primary pathology involved wrists with scapholunate advanced collapse, long-standing scaphoid non-unions and fragmented Kienbock’s disease. All patients had painful wrists limiting function preoperatively. Twenty wrists continue to function well with their PRC. They are comfortable and strong. Mass power grip was 77% of the non-injured side. A functional flexion/extension arc of 65 % of the non-injured side was obtained. No patients with functioning PRCs have had to change their work or recreational activities primarily because of their wrist. Rapid return to work and sport was achieved in the twenty patients with a well functioning PRC. Four wrists (from the first cohort) were converted to wrist fusion for unresolved pain all around a year post PRC. Three patients developed major reflex sympathy dystrophy requiring intensive therapy. Three patients developed carpal tunnel syndrome requiring decompression. PRC is appealing in its surgical simplicity as a motion preserving procedure for the painful wrist. In the majority of circumstances it is both reliable and durable providing a comfortable strong wrist with a functional range of movement. Rehabilitation is uncomplicated and function is rapidly recovered. Patients with ongoing pain can be salvaged with a wrist fusion.
