Complications and Reoperations after Carpal Tunnel Decompression: A Nationwide Cohort Analysis of Risk Factors in 855 838 Surgeries in the NHS in England

Abstract

Background: Healthcare related costs for carpal tunnel decompression surgery (CTD) to treat carpal tunnel syndrome (CTS) exceed two billion dollars per year, despite a scarcity of data on safety and effectiveness. We estimated the incidence of revision surgery and complications following CTD, and the patient factors associated with adverse outcomes. Methods: We included all CTD surgeries undertaken in England using the Hospital Episode Statistics dataset linked to mortality records from 01/04/1998 until 31/03/2017. Patients were followed up until death or 31/03/2017. Primary outcomes were the overall incidence of revision CTD and postoperative complications (surgical site infection or dehiscence requiring surgery, neurovascular or tendon injury) within 30 and 90 days of surgery. Multivariable Cox regression analysis was used to identify factors influencing complications and revision surgery. The Fine and Gray method was used to adjust for the competing risk of mortality. Findings: 855 838 CTDs were performed during the 19-year period (incidence rate 1.10 per 1000 person years [95% CI 1·02 to 1·17]). Complication rates were 0·07% (95% CI 0·067 to 0·078) within 30 days, 0·08% (95% CI 0·073 to 0·085) within 90 days. 90-day local complications were associated with male sex and age category 18-29 years (adjusted hazard ratios 2·32 [1·74 to 3·09], 2·25 [1·10 to 4·62] respectively). 3·4% underwent revision CTD (incidence rate 3·18 per 1000 person years [95% CI 3·12 to 3·23]). Male sex, increasing age, greater levels of comorbidity, and increasing socioeconomic deprivation were associated with increased revision risk (adjusted subhazard ratios 1·09 [95% CI 1·05 to 1·13]; 1·09 [1·03 to 1·15]; 1·25 [1·19 to 1·32] and 1·18 [1·10 to 1·27]). Interpretation: This is the largest national study on CTD to date, providing the best available evidence on complication and revision rates. CTD is a safe operation, with an overall complication rate of less than 0.1%. Funding: Versus Arthritis; Medical Research Council; RCS England/ NJR research fellowship; University of Oxford; National Institute for Health Research; NIHR Biomedical Research Centre, Oxford. Declaration of Interest: All authors have completed the ICMJE uniform disclosure and declare: no support from any organization for the submitted work; D P-A has received research grants from Amgen, Servier, UCB; departmental fees for speaker services from Amgen, departmental fees for consultancy from UCB. No other relationships or activities could appear to have influenced the submitted work. Ethical Approval: This study was approved by the University of Oxford Research Services Clinical Trials Research Group (project ID 12787), and the NHS Data Access Advisory Group (DAAG). It was carried out in accordance with the NHS Digital Data Sharing Agreement (DARS-NIC-29827-Q8Z7Q) and registered at clinicaltrials.gov (NCT03573765). Studies using non-identifiable records from Hospital Episode Statistics are exempt from research ethics committee approval.