Retrospective Study
Copyright ©The Author(s) 2019. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Orthop. Dec 18, 2019; 10(12): 454-462
Published online Dec 18, 2019. doi: 10.5312/wjo.v10.i12.454
Factors associated with trigger digit following carpal tunnel release
Jacob Nosewicz, Carla Cavallin, Chin-I Cheng, Neli Ragina, Arno W Weiss, Anthony Zacharek
Jacob Nosewicz, Carla Cavallin, Neli Ragina, Central Michigan University College of Medicine, Mt. Pleasant, MI 48858, United States
Chin-I Cheng, Department of Statistics, Actuarial and Data Science, Central Michigan University, Mt. Pleasant, MI 48858, United States
Arno W Weiss, Anthony Zacharek, Covenant Plastic Surgery, Saginaw, MI 48602, United States
Author contributions: All authors helped to perform the research; Nosewicz J and Cavallin C contributed to manuscript writing, drafting conception and design, and data analysis; Cheng CI contributed to data analysis; Ragina N contributed to writing manuscript; Weiss AW and Zacharek A performed procedures and contributed to writing manuscript.
Supported by the Blue Cross Blue Shield of Michigan Foundation, No. 22590764.
Institutional review board statement: This study was reviewed and approved by the Covenant Healthcare Institutional Review Board.
Informed consent statement: Informed consent for the study was not required as determined by the Covenant Healthcare Institutional Review Board. All clinical data used was de-identified and kept anonymous throughout the research process.
Conflict-of-interest statement: There is no conflict of interest to disclose.
Data sharing statement: There is no additional data available.
Open-Access: This is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Corresponding author: Jacob Nosewicz, BSc, Central Michigan University College of Medicine, 1280 E Campus Drive, Mt. Pleasant, MI 48858, United States. nosew1j@cmich.edu
Telephone: +1-989-5837918 Fax: +1-989-7747881
Received: April 17, 2019
Peer-review started: April 18, 2019
First decision: July 30, 2019
Revised: September 30, 2019
Accepted: October 18, 2019
Article in press: October 18, 2019
Published online: December 18, 2019
ARTICLE HIGHLIGHTS
Research background

Carpal tunnel release (CTR) surgery consists of dividing the carpal tunnel ligament in order to decompress the median nerve. CTR is accomplished via either an open or endoscopic approach. Markedly, CTR surgery may predispose patients to trigger digit, a common orthopedic hand condition.

Research motivation

The association between surgical approach to CTR, either open or endoscopic, and postoperative trigger digit development remains equivocal.

Research objectives

Our study aimed to investigate patient risk factors for trigger digit development following CTR and whether these risk factors varied between open carpal tunnel release (OCTR) and endoscopic carpal tunnel release (ECTR).

Research methods

This retrospective chart analysis evaluated 967 CTR procedures from 694 patients for the development of postoperative trigger digit. Patients were stratified according to the technique utilized for their CTR, either open or endoscopic. The development of postoperative trigger digit was evaluated at three time points: within 6 mo following CTR, between 6 and 12 mo following CTR, and after 12 mo following CTR. Firth’s penalized likelihood logistic regression was conducted to evaluate sociodemographic and patient comorbidities as potential independent risk factors for trigger digit. Secondary regression models were conducted within each surgical group to reveal any potential interaction effects between surgical approach and patient risk factors for the development of postoperative trigger digit.

Research results

There was no significant difference between the ECTR and OCTR groups to develop trigger digit at all three postoperative time markers. Furthermore, there were no significant individual predictors revealed for the development of trigger digit following CTR; however, within group analysis revealed a significant interaction effect between gender and surgical approach. This significant interaction effect between gender and surgical approach was confirmed in the primary multivariable logistic regression model (P = 0.008). Females were more likely to develop postoperative trigger digit than males after OCTR(OR = 3.992), but were less likely to develop postoperative trigger digit than males after ECTR (OR = 0.489).

Research conclusions

Our study found that patient comorbidities do not influence the development of trigger digit following CTR. Markedly, gender differences for postoperative trigger digit may depend on surgical approach to CTR. We are the first to report gender as a potential risk factor for trigger digit following CTR. Females were as likely as males to develop trigger digit when controlling for surgical approach as an independent variable; however, the effect of gender became significant when patients were stratified into separate surgical groups.

Research perspectives

Current studies evaluating structural changes in the postoperative carpal tunnel do not make comparisons between genders. A prospective randomized intervention study is needed to confirm the gender differences we found between ECTR and OCTR. We also suggest the use of magnetic resonance imaging to compare changes in the morphological differences of the postoperative carpal tunnel, including volar migration.