Stacked-Blade, Single-Cut, Ulnar-Shortening Osteotomy

Abstract

The authors reviewed a 10-year consecutive series of ulnar-shortening osteotomies using a freehand, single oblique cut with 2 or 3 stacked saw blades. Twenty-one patients (23 wrists) with chronic ulnar impaction syndrome (mean age, 45 years; range, 16 to 73 years) demonstrated an average preoperative ulnar variance of +2.1 mm (range, 0.0 to 4.0 mm). An oblique osteotomy was performed in the distal one-third of the ulnar diaphysis at an estimated 45° or 60° angle, relative to the ulnar axis, and was fixed with a 7-hole, 2.7- or 3.5-mm dynamic compression plate placed dorsally. Using a previously described formula, the authors estimated ulnar shortening on the basis of intraoperative measurement of kerf width and osteotomy angle as 3.3 mm (range, 2.3 to 4.7 mm). The actual measured average radiographic change in ulnar variance (preoperative to postoperative) was 2.8 mm (average 18% variance from intraoperative estimate). Final ulnar variance averaged -0.6 mm (range, -2.0 to 1.0 mm). Radiographic union occurred in all 23 (100%) osteotomies. Ten (43%) wrists required hardware removal for pain; 2 additional patients were symptomatic but declined removal. Ulnar-sided wrist pain was relieved in 22 wrists. This technique is simple, effective, and inexpensive. It can also be translated for use in shortening osteotomies for other long bones, although larger or smaller saw blades may be necessary for larger or smaller bones to achieve the desired amount of shortening. The authors' results also show it to be reasonably predictable, although the intraoperative use of a sterile goniometer for cut placement is recommended.