The AO Ulnar Shortening Osteotomy System Indications and Surgical Technique

Abstract

Ulnar shortening osteotomy is an established and frequently performed surgical procedure in wrist surgery. The technical aspects of the procedure have continued to develop in recent years, with instruments and implants being developed specifically for this purpose. Ulnar shortening osteotomy is required for different clinical indications and situations. These varying indications demand different amounts of shortening, but all must be precise and accurate. Controversy exists as to how this can best be achieved in terms of the location for osteotomy, the surgical approach and geometry of the osteotomy, as well as which implant to use to provide optimal stability. The goal of all techniques (besides successfully resolving the underlying problem) is to achieve reliable and rapid bone union without compromising early functional rehabilitation and also to avoid hardware complications. The AO Hand Expert Group has developed a specialized instrumentation system with dedicated and specifically designed implants to ensure exact and accurate cutting with precise and rigid stabilization of the ulna. The matched drill guides and double-blade saws allow accurate completion of the planned amount of shortening together with precise coaptation of the osteotomy fragments. The specific ulnar osteotomy LCP (locking compression plate) combines maximum stability with minimum bulk and soft tissue irritation. The features of the implant, its surgical technique, and early results are described.

Enabling the design of surgical instruments for under-resourced patients through metal additive manufacturing: ulnar shortening osteotomy as an example

“…Technical notes have been published to improve the reproducibility of free-hand ulnar shortening osteotomy [9]. To optimize usability and precision, several commercially available USO systems have been developed [7,8]. However, those systems are not widely available.…”

“…To optimize the outcome of USO and minimize the possibility of nonunion, a precise osteotomy and firm fixation is warranted. Therefore, various companies have developed ulnar shortening systems, providing an easy cutting and fixation workflow [6][7][8]. However, many patients can not afford the cost of those systems, and most of these USOspecific cutting systems can not be applied to traditional dynamic compression plates or regular locking plates, which poses lower out of pocket cost.…”

Is ulnar shortening osteotomy or the wafer procedure better for ulnar impaction syndrome?: A systematic review and meta-analysis

“…Compared to the popular freehand osteotomy technique, several companies started to launch specialized shortening osteotomy systems since 2005. [30][31][32][33] These systems facilitate USO with precise and parallel osteotomy, and subsequently, the incidence of delayed or nonunion is expected to decrease. [32][33][34][35][36] Furthermore, advancement and revision in the future will enable more stable and consistent USO.…”

Ulnar Impaction Syndrome and TFCC Injury: Their Relationship and Management

“…Although USO has the effect of reducing ulnocarpal loading and successful results have been reported in good/excellent outcomes in 73 to 94% of patients, 44,45 there have been various studies of fixation device designs, fixation side, and osteotomy sites to reduce complications such as nonunion and hardware irritation. [46][47][48][49][50][51][52] The Wafer procedure is also a good surgical option with minimal invasiveness, and favorable results have been reported. 45,[53][54][55] However, since the articular cartilage of the ulnar head is removed and carpal cartilage erosion may occur, the noncartilage surface of the ulna and carpal bone as well as DRUJ must be brought into contact and arthritic changes might be brought (►Fig.…”