Use of the trans-scaphoid portal for the arthroscopic treatment of scaphoid nonunion in the middle third with flexion deformity: technique description and patient series

Nonunion is one of the main complications associated with scaphoid fractures. Over the past decades, the use of arthroscopy in the treatment of scaphoid nonunion has proven to be a valuable technique, even in cases presenting deformity and carpal instability. This approach facilitates rapid consolidation while minimizing damage to the joint capsule and ligaments, thereby preserving the already compromised vascular supply of the scaphoid. Due to their simpler anatomy, dorsal portals are commonly employed in wrist arthroscopy, reducing the risk of injury to neurovascular structures during joint access. Initial descriptions of arthroscopic treatment for scaphoid nonunion (SNU) used only dorsal portals throughout the procedure. However, correcting the scaphoid's flexion deformity caused the dorsal cortex to close and created a defect in the volar portion, introducing a technical challenge. Herein, we describe a novel access portal to assist in the arthroscopic treatment of mid-third scaphoid nonunion, which we have termed the trans-scaphoid portal. Located volar and distal to portal 1/2, just volar to the first extensor tendon compartment, it allows direct lateral access to the nonunion site. We used this portal in 10 patients with excellent results, observing that it simplified the correction of the scaphoid flexion deformity and allowed for direct placement of the bone graft in the volar region. The trans-scaphoid portal was developed to overcome the limitations of dorsal portals, enabling safe and straightforward debridement of the lesion, correction of deformity, and easier graft placement into the volar defect.