RESURFACING HUMERAL ARTHROPLASTY FOR ROTATOR CUFF TEAR ARTHROPATHY: EARLY CLINICAL OUTCOME

Abstract

Hemiarthroplasty has been accepted as a viable alternative in the treatment of painful arthritis due to massive rotator cuff failure in patients with well-preserved functional active forward elevation of the shoulder. Unfortunatley, the early clinical results and long-term durability of hemiarthroplasty for rotator cuff tear arthropathy (RCTA) have been inferior to those seen in other disorders, most notably concentric osteoarthritis. Concern regarding the potential need for revision to a reverse shoulder arthroplasty has given rise to the notion of a resurfacing prosthesis as a primary procedure rather than a traditional stemmed-hemiarthroplasty in the hopes of reducing procedural and postoperative complications.

Eleven resurfacing humeral arthroplasties (Global CAP, Depuy) were performed for RCTA as a primary arthroplasty. There were six males and five females, average age of 74.7 years. 36% had undergone previous surgery on the affected side. All had failed a minimum of one year of non-operative treatment prior to surgery. Follow-up averaged eight months (range 4–12).

Prospective mean data analysis showed an improvement in all scales from preoperative baseline levels inclusive of the SST (3.5–6), ASES assessment form (8–17.5), Constant score (49–79) and the DASH (50–27). Mean active forward elevation remained relatively unchanged (one hundred and nine to one hundred degrees), while mean active external rotation improved (thirty-three to fifty-four degrees). Mean computerised muscle testing showed improvement in both elevation (5.1–7.7 N/m) and external rotation strength (2.6–5 N/m). Radiographic analysis has not shown any evidence of implant loosening to date.

Resurfacing humeral arthroplasty seems to demonstrate early favorable clinical results in this group of patients with RCTA. This may serve as an alternative to a stemmed-hemiarthroplasty in these patients and possibly result in a less complicated revision to a reverse prosthesis in the future should this be deemed necessary. Given these results are early, ongoing clincal followup will be necessary to define the longer-term durability of this procedure.