Arthroscopic Assisted Combined Dorsal and Volar Scapholunate Ligament Reconstruction with Tendon Graft for Chronic SL Instability
Pak-cheong Ho, Clara Wing-yee Wong, Wing-lim Tse
Department of Orthopaedic and Traumatology, Prince of Wales Hospital, Chinese University of Hong Kong, Hong Kong SAR
Background: Both dorsal and volar portion of the scapholunate interosseous ligaments are the major stabilizers of the scapholunate (SL) joint. Most reconstruction methods to restore scapholunate stability do not address the volar constraints and frequently fail to reduce the SL gapping. Wrist arthroscopy allows a complete evaluation of the SL interval, accompanying ligament status and associated SLAC wrist changes. It enables simultaneous reconstruction of the dorsal and palmar SL ligaments anatomically with the use tendon graft in a box-like structure.
Materials and Methods: From October 2002 to May 2018, 30 cases had been performed in our institute. This study evaluated the outcome in the first 17 patients with chronic symptomatic SL instability till June 2012. The average duration of symptom was 9.5 months (range 1.5-18 months). There were 3 Geissler grade 3 and 14 grade 4 instability cases. The average pre-op SL interval was 4.9mm (range 3-9mm). DISI deformity was present in 13 patients. Six patients had stage 1 SLAC wrist change radiologically. Concomitant procedures were performed in 4 patients. Description of Technique With the assistance of arthroscopy and intra-operative imaging guide, a combined limited dorsal and volar incision exposed the dorsal and palmar SL interval without violating the wrist joint capsule. Bone tunnels of 2.4mm were made on the proximal scaphoid and lunate in convergent manner. A palmaris longus tendon graft was delivered through the wrist capsule and the bone tunnels to reduce and connect the two bones in a box-like fashion. Once the joint diastasis was reduced and any DISI malrotation corrected as verified through arthroscopy, the tendon graft was knotted and sutured on the dorsal surface of SL joint extra-capsularly in shoe-lacing manner, thus augmenting the strength of the extrinsic ligaments and the secondary stabilisers of the scapholunate complex as well. Depending on the stability of the fixation, the scaphocapitate joint could be transfixed with K wires to protect the reconstruction for 6-8 weeks.
Results: The average follow up was 48.3 months (range 11-132 months). Thirteen patients returned to their pre-injury job level. Eleven had no wrist pain and 6 had some pain on either maximum exertion or at the extreme of motion. The average total pain score was 1.7/20 compared with the preoperative score of 8.3/20. The post-operative average total wrist performance score was 37.8/40, with an improvement of 35%. The average extension range improved for 13%, flexion range 16%, radial deviation 13% and ulnar deviation 27%. Mean grip strength was 32.8kg. (120% of the pre-operative status, 84% of the contralateral side) The average SL interval was 2.9mm (range 1.6- 5.5mm). Recurrence of a DISI deformity was noted in 4 patients without symptoms. Ischaemic change of proximal scaphoid was noted in one case without symptoms or progression. There were no major complications. All patients were satisfied with the procedure and outcome.
Conclusion: Our method of reconstructing both the dorsal and volar SL ligament, in a minimally invasive way, is a logical and effective technique to improve the SL stability. The potential risk of ischemic necrosis of the carpal bone is minimized by preservation of the scaphoid blood supply, the small size of the bone tunnels created and the inclusion of the capsule at the reconstruction site.
Back to 2020 Abstracts