Radiographic Evaluation of the Modified Brunelli Technique Versus the Blatt Capsulodesis for Scapholunate Dissociation in a Cadaver Model

Abstract

A variety of soft tissue surgical procedures have been developed for treatment of scapholunate (SL) dissociation. The purpose of this study was to compare the degree of correction obtained (as measured on preoperative and postoperative radiographs) when performing the modified Brunelli technique (MBT) with that of the more commonly performed Blatt capsulodesis (BC) and to evaluate each technique after simulated wrist motion. Five cadaver wrists were used for this study. The SL interval, SL angle, and radiolunate angle were recorded radiographically, with the SL ligament intact, for each wrist in several loaded positions: neutral, flexion, extension, radial deviation, ulnar deviation, and clenched fist. The SL interosseous ligament was then completely incised, and the radiographic measurements were repeated to demonstrate SL instability. The radiographic measurements were then repeated after MBT reconstruction and after BC reconstruction. Additional radiographic measurements were taken after simulated wrist motion. Sectioning of the SL ligament resulted in radiographic evidence of SL dissociation. Use of the MBT demonstrated improved correction of the SL interval and the SL angle in the clenched fist position, which was statistically significant when compared with BC. The correction for the SL angle was maintained on the MBT specimens with simulated wrist motion. The results demonstrate that in this cadaver model, the MBT better restores the normal carpal relationship of the SL interval and SL angle when compared to the BC, as measured on radiographs. This correction might correlate with improved carpal dynamics and improved clinical outcomes.