TY - JOUR AU - Bain, Gregory I.; Krishna, Sathya Vamsi; MacLean, Simon; Carr, Renee; Slavotinek, John TI - “Locked” Scapholunate Instability Diagnosed with 4D Computed Tomography Scan SN - 2163-3916 SN - 2163-3924 PY - 2019 JO - J Wrist Surg JF - Journal of Wrist Surgery LA - EN VL - 08 IS - 04 SP - 321 EP - 326 ET - 2019/01/10 DA - 2019/08/07 KW - scapholunate instability KW - locked scapholunate instability KW - scaphoid dislocation KW - carpal KW - instability KW - 4D CT scan AB - Background Scapholunate instability (SLI) has a wide range of clinical and radiological presentations. The management depends on the stage of the disorder. Subluxation of scaphoid is pathognomonic feature of the SLI. We describe a patient with SLI with a dislocated proximal pole of scaphoid, out of the distal radius scaphoid fossa. The 4D (three-dimensions + time) computed tomography (CT) scan demonstrated that the scaphoid did not reduce throughout wrist motion.Case Description A 20-year-old male presented with SLI following a fall skateboarding. The 4D CT scan revealed the dislocated scaphoid that did not reduce with wrist motion. He underwent open reduction of the proximal pole of scaphoid and SL reconstruction using flexor carpi radialis (FCR) tendon graft with the Quad tenodesis technique. At 1 year, he had improved pain, wrist functions, and maintained satisfactory radiological alignment.Literature Review We are not aware of any previous description of the dorsal scaphoid dislocation in association with scapolunate instability.Clinical Relevance We recommend that the SLI staging classification needs to be expanded to include dislocation (locked) stage. The 4D CT has a significant role in identifying the instability and its reducibility.Level of Evidence This is a level V study. PB - Thieme Medical Publishers DO - 10.1055/s-0038-1675385 UR - http://www.thieme-connect.com/products/ejournals/abstract/10.1055/s-0038-1675385 ER -