To elucidate the performance of carpometacarpal-I joint prostheses in comparison with the current gold standard treatment, resection-suspension arthroplasty (RA), we conducted a study comparing outcomes of the Ivory prosthesis to those of a cohort of patients receiving RA.
Initially, we had enrolled 34 prosthesis patients and 48 RA patients, of which 5 and 11 were lost to follow-up. We defined Eaton/Littler stage 3 osteoarthritis, no previous surgery, no concomitant arthrosis, no rheumatic arthritis, no history of trauma and a minimum follow-up period of 2 years as inclusion criteria. We assessed patient demographics, disability of the arm, shoulder, and hand score, pain via visual analogue scale, subjective strength of the thumb, range of motion (radial and palmar abduction and opposition), and patient satisfaction. All occurring complications were recorded.
Follow-up included a mean period of 4.5 years (2-7.4) in the prosthesis cohort and 4.1 years (2-6.8) in the RA group. Disability of the arm, shoulder, and hand scores, pain scores, palmar abduction and opposition, and subjective satisfaction showed no significant differences between the two cohorts. Postoperative loss of strength was significantly less in the prosthesis group (p = 0.01). Moreover, we were able to demonstrate better range of motion in terms of radial abduction in the prosthesis group (p = 0.001). The overall complication rate was significantly higher in the prosthesis cohort (41.4% vs. 10.8%) (p = 0.008). Nevertheless, the Ivory prosthesis group showed a survival rate of 93.1%.
As the high complication rate is compensated by a better functional outcome (enhanced range of motion and strength), we believe that prosthesis implantation can be a reasonable treatment option for carpometacarpal-I osteoarthritis in a particular patient group. Level of Evidence IIIl: Retrospective cohort study.