David Nelson Hand Surgery Greenbrae Marin hand specialist surgery of the hand orthopedics San Francisco



Endoscopic Carpal Tunnel Release

This is an article from the Journal of Bone and Joint Surgery about endoscopic carpal tunnel. If you are interested in endoscopic surgery, please read the Abstract and then see my commentary at the end of the page. The full article is available online (the Journal charges for some access) or at the MGH Medical Library ( 925-7393).

Journal of Bone and Joint Surgery, July, 2002

Single-Portal Endoscopic Carpal Tunnel Release
Compared with Open Release

A Prospective, Randomized Trial

Thomas E. Trumble, MD, Edward Diao, MD, Reid A. Abrams, MD and Mary M. Gilbert-Anderson, MA

Investigation performed at the Department of Orthopaedics, University of Washington Medical Center, Seattle, Washington; the Department of Orthopaedic Surgery, University of California, San Francisco, California; and the Department of Orthopaedics, University of California, San Diego, California

Thomas E. Trumble, MD
Mary M. Gilbert-Anderson, MA
Department of Orthopaedics, Box 356500, 1959 N.E. Pacific Street, University of Washington Medical Center, Seattle, WA 98195. E-mail address for T.E. Trumble: trumble@u.washington.edu

Edward Diao, MD
Department of Orthopaedic Surgery, University of California, San Francisco, 500 Parnassus Avenue, MU-320-West, San Francisco, CA 94143

Reid A. Abrams, MD
Department of Orthopaedics, University of California, San Diego, 350 Dickinson Street, Mailcode 8894, San Diego, CA 92103

In support of their research or preparation of this manuscript, one or more of the authors received grants or outside funding from the Orthopaedic Research and Education Foundation, The American Society for Surgery of the Hand, and the Boeing Foundation. None of the authors received payments or other benefits or a commitment or agreement to provide such benefits from a commercial entity. No commercial entity paid or directed, or agreed to pay or direct, any benefits to any research fund, foundation, educational institution, or other charitable or nonprofit organization with which the authors are affiliated or associated.


Background: Carpal tunnel syndrome is a common condition causing hand pain and numbness. Endoscopic carpal tunnel release has been demonstrated to reduce recovery time, although previous studies have raised concerns about an increased rate of complications. The purpose of this prospective, randomized study was to compare open carpal tunnel release with single-portal endoscopic carpal tunnel release.

Methods: A prospective, randomized, multicenter center study was performed on 192 hands in 147 patients. The open method was performed in ninety-five hands in seventy-two patients, and the endoscopic method was performed in ninety-seven hands in seventy-five patients. All of the patients had clinical signs or symptoms and electrodiagnostic findings consistent with carpal tunnel syndrome and had not responded to, or had refused, non operative management. Follow-up evaluations with use of validated outcome instruments and quantitative measurements of grip strength, pinch strength, and hand dexterity were performed at two, four, eight, twelve, twenty-six, and fifty-two weeks after the surgery. Complications were identified. The cost of the procedures and the time until return to work were recorded and compared between the groups.

Results: During the first three months after surgery, the patients treated with the endoscopic method had better Carpal Tunnel Syndrome Symptom Severity Scores, better Carpal Tunnel Syndrome Functional Status Scores, and better subjective satisfaction scores. During the first three months after surgery, they also had significantly (p < 0.05) greater grip strength, pinch strength, and hand dexterity. The open technique resulted in greater scar tenderness during the first three months after surgery as well as a longer time until the patients could return to work (median, thirty-eight days compared with eighteen days after the endoscopic release). No technical problems with respect to nerve, tendon, or artery injuries were noted in either group. There was no significant difference in the rate of complications or the cost of surgery between the two groups.

Conclusion: Good clinical outcomes and patient satisfaction are achieved more quickly when the endoscopic method of carpal tunnel release is used. Single-portal endoscopic surgery is a safe and effective method of treating carpal tunnel syndrome.

Dr. Nelson's Comments

This is a very detailed article about the advantages of endoscopic carpal tunnel release (ECTR), in the hands of experienced surgeons, most of whom I know and respect. However, I am unconvinced of its superiority to open carpal tunnel release (OCTR) in my hands. Let me explain.

The main advantages of ECTR, as listed in this article as well as the articles of the originator of the procedure, my friend Dr. John Agee, are (1) less pain, and (2) quicker return to work. In addition, they claim (3) no increased risk from the procedure. Let us look at each of these claims in turn.


I have done a 3-year, prospective, Institutional Review Board-approved study of all my patients who have had surgery (not just the ones who have had open carpal tunnel release, which is a very minor surgery). I found that 46% of my patients never took any narcotics, and the average number taken was 2.26. I have not done a subset of carpal tunnel patients, but I would estimate (I realize that this is not science) that 90% never took any narcotics after surgery, only Tylenol and an anti-inflammatory (Vioxx) pill. It is hard to do surgery and have less pain than that! I cannot directly relate my patients to this study's, since our methods are different, but I see no advantage in terms of pain for the ECTR, so I don't do it.

Return to Work

I have done a prospective, consecutive patient study in my own practice of open carpal tunnel release patients, who are covered by Workers' Compensation Insurance. (That is, the patients are paid to stay home and not return to work! This is the toughest group to get back to work!) There were 18 patients in the study. The average time to return to work was 19 days. The study above had a return to work time of 38 days. My patients with open carpal tunnel release return to work faster than the ECTR patients. There is no advantage in return to work rate in my patients, so I don't do ECTR. Since I performed my study, my normal return to work time is now 14 days after surgery.


The above study claimed to have no complications, and I am sure that they are reporting their results correctly. However, I do not think that this represents reality. For instance, Dr. Palmer has reported hundreds of complications related to both ECTR and OCTR. The complications with OCTR tended to occur with residents doing their first cases, and the ECTR complications tended to occur with experienced surgeons. I have not yet had any complications in my own OCTRs.

Confused? Here are my Conclusions

The decision to do surgery is always a balancing act between possible benefits and possible risks. Due to the fact that:

(1) my patients treated with OCTR return to work faster than the published studies of ECTR, and

(2) my patients treated with OCTR have minimal pain and, from my best estimates from talking to surgeons who do ECTR, less pain than their patients do, and

(3) the published risks of ECTR, while small, are higher than my own experience with OCTR

I only do open carpal tunnel release. In my hands, there are no increased benefits and there are increased risks, and my results are better than the published series.

I had bilateral simultaneous CTR myself in 2003, and had it done OPEN, not endoscopically.

I would be pleased to discuss this with you in the office.