Twenty-Year Experience With Primary Distal Radioulnar Joint Arthroplasty From a Single Institution.

ABSTRACT

PURPOSE: The use of implant arthroplasty in the distal radioulnar joint is increasing. Two main types of implants are commonly used, ulnar head prosthesis (UHP) and hemi or semi-constrained total distal radioulnar joint arthroplasty. The literature consists mainly of small patient series. The purpose of this study was to examine our long-term outcomes of distal radioulnar joint arthroplasty. METHODS: Patient data were collected in a patient registry from 2000 to 2019. The follow-up included radiographic examination, physical examination, Mayo Wrist Scores, pain level, range of motion, and grip strength. Reoperations were recorded. The implants were a semi-constrained prosthesis and a metallic UHP. The mean age at surgery was 50 years. Patient demographics were similar, but the semi-constrained group had a higher preoperative percentage of instability (85 vs 52 percent). The median follow-up time was 30 months for the semi-constrained implants group and 102 months for the UHP group. RESULTS: A total of 53 primary semi-constrained total joint arthroplasties and 102 UHPs were included. The grip strength and Mayo Wrist Score improved for both the implant groups. Pain reduced in 76% of the patients. Supination improved for the semi-constrained total joint arthroplasty group. Lifting capacity was better in the semi-constrained total joint arthroplasty patients. The unadjusted reoperation rate was 23% for the semi-constrained implants group and 34% for the UHP group. Twenty-two implants were bilateral; these had comparable results to unilateral implants. Kaplan-Meier survival curves demonstrated 94% survival rate for the semi-constrained implants group and 87% survival for the UHP group after 5 years. The risk factors associated with reoperation for the combined implant group included younger age at surgery, previous wrist surgery, ulnar shortening, and wrist fusion. CONCLUSIONS: Distal radioulnar joint arthroplasty improved functional outcomes in both the implant groups, but reoperations were frequent. The semi-constrained implants group had better lifting capacity. The bilateral implants had comparable outcomes to the unilateral implants. TYPE OF STUDY/LEVEL OF EVIDENCE Therapeutic IV.