Ulnar shortening osteotomy for ulna impaction syndrome with positive ulnar variance: retrospective outcome analysis.

Background And Purpose:  We primarily aimed to report the results of ulnar shortening osteotomy (USO) in cases of ulna impaction syndrome (UIS), and secondarily to assess the influence of etiology, radiographic parameters, and comorbidities on the outcome.

Methods:  Patients with USO performed for UIS between 2014 and 2022 at our department were included in the study. Demographic, surgical, and postoperative data, including complications and revisions, were recorded retrospectively. An additional study-specific follow-up was performed in all available cases, including subjective outcome measures as Patient Related Wrist Evaluation (PRWE) and Quick Disability of the Arm Shoulder and Hand (Quick-DASH) scores, and standardized 90-90° wrist radiographs.

Results:  47 patients were treated with USO at mean age 45.8 years (standard deviation [SD] 16.7); 28 were female; median follow-up was 37 months (interquartile range [IQR] 22-57). Isolated USO was performed in 27 cases; the rest received a combination of procedures, e.g., wrist arthroscopy. USO-specific devices were used in all cases. Reoperations were performed in 12 cases, with implant removal in 11. Postoperative complications such as chronic regional pain syndrome or pseudoarthrosis were detected in 9 patients. 29 patients were additionally examined at median 36 months (IQR 22-49) follow-up. A median PRWE score of 7 (IQR 0-19) and a median Quick-DASH score of 4.5 (IQR 0-15.9) were reported. The subjective improvement was rated as very high by 24 patients. Radiographs showed a mean ulnar shortening of 2.9 mm (SD 1.1) and bone consolidation was achieved in all osteotomies at last follow-up. Relevant comorbidities weakly correlated with worse outcome scores (ρ = 0.41, 95% confidence interval [CI] -0.05 to 0.74 for PRWE and ρ = 0.40, CI -0.06 to 0.73 for Quick-DASH). No statistically significant difference could be detected in any other variables, including UIS etiology.

Conclusion:  We found that USO had good subjective results measure scores, but with relatively high complication and revision rates, including implant removal.