[Proposal for new anterior portals for wrist arthroscopic as a complementary approach to open anterior wrist surgery]

Morphological and morphometric studies of the wrist ligaments are scarce. The radiocapitatum and scapholunate ligaments play a pivotal role in wrist stability. Classically, a posterior approach is used for arthroscopic procedures, but an anterior approach should be possible. We conducted a cadaver study to search for new anterior portals for wrist arthroscopy.

Twenty-five formol-treated upper limbs were dissected. The classical anterior approach for open wrist surgery was executed. The different elements of the capsule-ligament system of the anterior aspect of the wrist were identified and labeled. The dissection was then extended to the ulna in search of soft points which were identified and evaluated. The different structures generally identified during wrist arthroscopy were noted.

Two potential portals were identified in all wrists: one between the radiolunate ligament and the radio-scapho-capitatum ligament on the radial aspect and one between the radio-lunate ligament and the ulno-lunate ligament. Arthroscopic exploration enabled observation of the scapho-lunate ligament, the luno-triquetral ligament, the triangular complex of the carpus, and the entire inferior aspect of the radial joint surface, with no risk of vessel or nerve injury because of the exposure allowed by the osteosynthesis approach.

Wrist arthroscopy is now accepted as a reliable technique not only for diagnostic purposes but also for therapeutic interventions for the treatment of fractures of the lower radius. Most of the arthroscopic portals described in the literature are posterior. The anterior portals described here do not involve any vascular or neurological risk since the radial approach is made under visual control by extension of the open anterior approach and on the ulnar side the noble structures are positioned medially to the ulnar flexor tendon of the carpus. This enables good triangulation necessary for the usual arthroscopic procedures. Finally, these portals have no supplementary morbidity which would be the case with percutaneous portals (injury to the medial nerve, the radial vasculonervous bundle, the radial flexor tendon).

These new arthroscopic portals are complementary to the anterior approach for open wrist surgery and enable a natural extension of joint exploration via both the radial and ulnar approaches described in this study.