title: Results of endoscopic carpal tunnel release relative to surgeon experience with the Agee technique.
abstract: OBJECTIVE
  To establish the rate of iatrogenic injury after endoscopic carpal tunnel release (ECTR) for a surgeon in the first 2 years of practice; to report the rate of conversion from ECTR to open carpal tunnel release (OCTR), the reason for conversion, and any increase in morbidity found in patients converted to OCTR; and to determine whether the conversion rate decreased with increasing surgeon experience.
  
  
  METHODS
  We conducted a retrospective review of patients undergoing ECTR by a single surgeon in the first 2 years of practice. Data collected or calculated included symptom relief, rate of conversion to OCTR, reason for conversion, and neurovascular complications. For patients converted to OCTR, we assessed satisfaction and function using the Disabilities of the Arm, Shoulder, and Hand questionnaire. We compared these results for 1 to 6 months, 7 to 12 months, and 12 to 24 months to determine whether a learning curve was present.
  
  
  RESULTS
  A total of 278 patients (358 procedures) underwent ECTR. Of these, 12 patients required conversion to OCTR during the index procedure over a 2-year period. In the first 6 months of practice, 8 of 71 ECTRs were converted to OCTR compared to 1 of 72 in the second 6 months. This was a statistically significant decrease (p = .017). In year 2, 3 of 215 patients were converted to OCTR. Average Disabilities of the Arm, Shoulder, and Hand score for patients converted from ECTR to OCTR was 9. No patients required repeat surgery for recurrence of carpal tunnel symptoms. We observed no major neurovascular complications.
  
  
  CONCLUSIONS
  A learning curve for ECTR was present. Rates of conversion significantly diminished with increased surgeon and anesthesia experience. Patients requiring conversion showed no variation in Disabilities of the Arm, Shoulder, and Hand scores from established values after OCTR. Patients may be at a higher risk of conversion to OCTR during the learning curve time period; nevertheless, we found no increased morbidity.
  
  
  METHODS
  Prognostic III.
authors.affiliation: Geisinger Orthopaedics, Danville, PA, USA. jdbeck1@gmail.com
authors.forename: John D
authors.initials: JD
authors.lastname: Beck
authors.forename: John H
authors.initials: JH
authors.lastname: Deegan
authors.forename: Diana
authors.initials: D
authors.lastname: Rhoades
authors.forename: Joel C
authors.initials: JC
authors.lastname: Klena
mesh_terms: D002349:Carpal Tunnel Syndrome / Q000453:epidemiology / Q000601:surgery*; D002983:Clinical Competence; D015897:Comorbidity; D004724:Endoscopy; D005260:Female; D006801:Humans; D008297:Male; D019635:Neurosurgical Procedures; D017060:Patient Satisfaction; D012189:Retrospective Studies; D016896:Treatment Outcome; D052582:Trigger Finger Disorder / Q000453:epidemiology