title: Diagnosis and anatomic reconstruction of extensor carpi ulnaris subluxation.
abstract: OBJECTIVE
  To evaluate the efficacy of dynamic ultrasound to diagnose extensor carpi ulnaris (ECU) subluxation and assess the results of a new technique for anatomic ECU tendon sheath reconstruction.
  
  
  METHODS
  Dynamic ultrasound was used to confirm the diagnosis of ECU tendon subluxation in patients presenting with painful snapping of the ulnar wrist during supination and pronation. Twenty-one patients with persistent subluxation had reconstruction of the ECU tendon sheath using a new technique. In this procedure, the ECU tendon is elevated within its sheath dorsally and radially. The distal ulnar groove is deepened with a power burr, and 2 or 3 suture anchors are placed along the ulnar margin of the reconstructed groove. The sutures are passed through the ulnar border of the ECU sheath and tied, securing tendon sheath to bone. Preoperative wrist flexion-extension, radial-ulnar deviation, pronation-supination, grip strength, and ratings of pain, satisfaction, and Disabilities of the Arm, Shoulder, and Hand (DASH) scores were recorded and compared with postoperative values in a prospective study. Fourteen male patients and seven female patients were followed from 24 to 45 months postoperatively (mean, 31 mo).
  
  
  RESULTS
  Twenty-one patients presented with symptomatic ECU tendon subluxation confirmed by dynamic ultrasound of the wrist. We noted a statistically significant increase in arc of wrist flexion-extension, radial-ulnar deviation, pronation-supination, and grip strength after reconstruction. There was a statistically significant improvement in pain, satisfaction, and DASH scores after ECU stabilization.
  
  
  CONCLUSIONS
  Dynamic ultrasound is an effective and noninvasive method of diagnosing ECU tendon subluxation. Our technique of anatomic ECU tendon sheath reconstruction improved postoperative wrist range of motion, grip strength, pain, satisfaction, and DASH scores.
  
  
  METHODS
  Therapeutic IV.
authors.affiliation: Department of Orthopaedics and Sports Medicine, University of Washington School of Medicine, Seattle, WA 98105-4743, USA.
authors.forename: Allison J
authors.initials: AJ
authors.lastname: MacLennan
authors.forename: Nicholas M
authors.initials: NM
authors.lastname: Nemechek
authors.forename: Thanapong
authors.initials: T
authors.lastname: Waitayawinyu
authors.forename: Thomas E
authors.initials: TE
authors.lastname: Trumble
mesh_terms: D000293:Adolescent; D000328:Adult; D001178:Arthroplasty / Q000379:methods*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D004204:Joint Dislocations / Q000000981:diagnostic imaging* / Q000601:surgery*; D008023:Ligaments, Articular / Q000601:surgery*; D008297:Male; D016059:Range of Motion, Articular; D013710:Tendons / Q000601:surgery; D016896:Treatment Outcome; D014457:Ulna; D014463:Ultrasonography; D014955:Wrist Joint