Ulna shortening osteotomy versus arthroscopic wafer procedure in the treatment of ulnocarpal impingement syndrome

Abstract

Post-traumatic or constitutional ulnar impaction syndrome can be treated by shortening the ulna. This can be achieved by diaphyseal or metaphyseal osteotomy, or by arthroscopic epiphyseal resection. The objective of this study was to compare the results of the diaphyseal shortening osteotomy (USO) and arthroscopic wafer procedure (AWP) of the ulna in this indication. This was a retrospective case series of 33 patients operated for ulnar impaction syndrome by the same surgeon between 1997 and 2017. The diagnosis was made based on pain on the ulnar edge of the wrist with positive provocative tests. Radiographs were made and CT arthrography or MRI were used to confirm the diagnosis. Per-and post-operative assessments were functional (DASH and PRWE scores), clinical (pain, range of motion and grip strength) and radiographic. Diaphyseal ulnar shortening osteotomy (USO) was performed in 9 patients using a volar plate and a cutting guide. Twenty-four patients underwent an arthroscopic wafer procedure. Mean follow-up was 103 ± 8 months in the USO group versus 55 ± 4 months in the AWP group. There was no significant difference between groups in pain levels (1.2/10 in the USO group versus 0.9/10 in the AWP group, p = 0.88), grip strength (39 Kg in the USO group versus 34 Kg in the AWP group, p = 0.27) and PRWE score (5,8/100 in the USO group versus 11,2 in the AWP group, p = 0.34), and DASH score (25/100 in the USO group versus 28 in the AWP group, p = 0.63). The time away from work was long in the USO group than in the AWP group (7.86 months versus 3.75 months) (p = 0.002). Seven patients were reoperated in the USO group (5 plate removal, 1 nonunion and 1 delayed union) versus 3 in the AWP group (1 ECU stabilization, 1 ablation for painful ulnar styloid due to nonunion and 1 wrist denervation) (p = 0.0004). The study found no clinical differences between these two techniques except the return to work time. In our series, diaphyseal USO was associated with a greater number of reoperations than the AWP.

Keywords: Arthroscopie; Arthroscopy; Conflit ulno-carpien; Ostéotomie raccourcissante de l’ulna; Shortening ulnar osteotomy; Ulnar impaction syndrome; Wafer procedure.