Interosseous SL Reconstruction for Chronic Scapholunate Dissociation augmented DIC stabilized by RASL vs Internal brace ligament augmentation

Objective

Staged 3 or 4 of SL dissociation according to 5 questions by Garcia is good candidate for reconstruction. How long should we need to keep K-wire after any ligament reconstruction? When can we achieve successful engraftment?

The results of Interosseous SL reconstruction as internal splint such as RASL and Internal brace ligament augmentation (=IBLA) were reviewed retrospectively.

Methods

Berger’ s approach was applied for all cases. Partial DIC was transferred to dorsal portion of SL ligament.12 patients were fixed by RASL were analyzed averaged followed up for 32.4 months. 15 patients were fixed using fiber tape with SwieveLock as IBLA were analyzed averaged followed up for 23 months. The three-dimensional kinematic analysis was performed after operation for each method.

Results

10/12 of RASL patients returned to previous occupation. 2 cases were converted to IBLA because of screw loosening. Breakage of double thread screw was occurred in 1 case. Postoperatively SL angle is reduced from 69 degrees to 40 degrees. SL gap is also reduced from 4.1 to 1.8 mm. There was no carpal collapse or progression to SLAC. 15/15 of IBLA patients returned to previous occupation. There was no progression of SL gap except for 1 case. Postoperatively SL angle is reduced from 72 degrees to 40 degrees. SL gap is also reduced from 5.3 to 1.2 mm. According to 3D analysis, normal scaphoid motion center axis is dorsal scaphoid. Distance between scaphoid apex and motion axis are different among normal, RASL, and IBLA. Kinematics of IBLA was closer to normal than that of RASL.

Discussion

 According to 3D kinematic analysis, IBLA is closer to normal compared to RASL, and better clinical result was obtained compared to RASL as internal splint.