Title: Woman With Pain and Deformity in Left Wrist
Abstract: A 19-year-old woman presented with left wrist deformity. She had a history of shoulder “hypermobility” and a childhood left ulnar fracture treated nonoperatively. She was stretching her arms with fingers intertwined when she felt a “pop” and left wrist pain. On examination, she had a minimally tender volar deformity at the ulnar styloid, with inability to pronate, limited supination, and preserved wrist flexion and extension. Posteroanterior, lateral, and oblique radiographs were obtained. Volar dislocation of the ulna at the distal radioulnar joint. Isolated volar dislocation of the ulna at the distal radioulnar joint without fracture is a rare diagnosis that is usually associated with trauma and may be missed in up to 50% of cases.1Kohyama S. Hara Y. Fukai R. et al.Subacute volar dislocation of the distal radioulnar joint without fracture: a case report and literature review.Trauma. 2014; 17: 229-234Crossref Scopus (5) Google Scholar, 2Mulford J.S. Jansen S. Axelrod T.S. Isolated volar distal radioulnar joint dislocation.J Trauma. 2010; 68: E23-E25Crossref PubMed Scopus (9) Google Scholar, 3Mittal R. Kulkarni R. Subsposh S.Y. et al.Isolated volar dislocation of distal radioulnar joint: how easy to miss!.Eur J Emerg Med. 2004; 11: 113-116Crossref PubMed Scopus (13) Google Scholar, 4Kumar A. Iqbal M.J. Missed isolated volar dislocation of distal radio-ulnar joint: a case report.J Emerg Med. 1999; 17: 873-875Abstract Full Text Full Text PDF PubMed Scopus (20) Google Scholar, 5Singletary E.M. Volar dislocation of the distal radioulnar joint.Ann Emerg Med. 1994; 23: 881-883Abstract Full Text Full Text PDF PubMed Scopus (18) Google Scholar Physical examination typically reveals a volar deformity with inability to pronate, with preserved flexion and extension. Subtle radiographic findings include overlap of the distal radius and ulna on oblique view (Figure 1) and volar displacement of the distal ulna beyond the radial cortices laterally (Figure 2). Comparative wrist radiographs can aid in the diagnosis.6Russo M.T. Maffuli N. Dorsal dislocation of the distal end of the ulna in a judo player.Acta Orthop Belg. 1991; 57: 442-446PubMed Google ScholarFigure 2Left wrist radiograph (lateral view) showing volar displacement of the distal ulna beyond the radial cortices (arrow).View Large Image Figure ViewerDownload Hi-res image Download (PPT) Closed reduction was successful (Figures 3 and 4), with 1% lidocaine injected into the joint space and then volar pressure on the ulnar head, with hyperpronation.Figure 4Left wrist radiograph (lateral view) showing reduction of the displaced distal ulna (arrow).View Large Image Figure ViewerDownload Hi-res image Download (PPT) Reduction may require general anesthesia or surgery.1Kohyama S. Hara Y. Fukai R. et al.Subacute volar dislocation of the distal radioulnar joint without fracture: a case report and literature review.Trauma. 2014; 17: 229-234Crossref Scopus (5) Google Scholar, 2Mulford J.S. Jansen S. Axelrod T.S. Isolated volar distal radioulnar joint dislocation.J Trauma. 2010; 68: E23-E25Crossref PubMed Scopus (9) Google Scholar, 3Mittal R. Kulkarni R. Subsposh S.Y. et al.Isolated volar dislocation of distal radioulnar joint: how easy to miss!.Eur J Emerg Med. 2004; 11: 113-116Crossref PubMed Scopus (13) Google Scholar, 4Kumar A. Iqbal M.J. Missed isolated volar dislocation of distal radio-ulnar joint: a case report.J Emerg Med. 1999; 17: 873-875Abstract Full Text Full Text PDF PubMed Scopus (20) Google Scholar After reduction, the wrist should be immobilized because the triangular fibrocartilage complex, dorsal radioulnar ligament, or joint capsule may be injured. Orthopedic follow-up is encouraged for possible magnetic resonance imaging.