Equal Results Between Open and Closed Carpal Tunnel Release
This study represents the results of long-term outcomes in patients treated for carpal tunnel syndrome with two different surgical approaches. One group had the more traditional open carpal tunnel release. The second group had an endoscopic release, which is an accepted, but not widely used, surgical procedure.

The first study published by this group of researchers involved the same two groups of patients. They reported on the short-term results using symptom severity and function (measured by return to work status) as the main measures of outcome.

The short-term period of time was one year. At that time, they could see that patients in the endoscopic group had less pain after the surgery. But there was no difference in number of days off work or functional status.

Using those same measures, the two groups were followed for another four years (total of a five-year follow-up period). The results after five years are the subject of this second, updated report. And here's what they found: there was no difference between the two groups using symptom severity, function, and work status as the reference standard.

Symptom severity included how often the pain woke the patient up at night, the presence of numbness or tingling, and the presence of pain in the scar or along the palm. Everyone in both groups got significant relief from the surgery. The majority of patients in both groups reported being very satisfied with the results of their treatment.

Patients in both groups were equally matched by age, preoperative work status (all were employed), symptoms lasting more than three months, and failure to respond to conservative care with wrist splinting. All patients had a positive nerve conduction test showing that the median nerve was sending motor or sensory messages through the carpal tunnel more slowly than normal.

After surgery, both groups were treated the same in terms of a rehab program. They were told to start moving the fingers and using the hand and wrist in anyway that was not painful. A supervised hand therapy program was not part of the rehab or recovery process.

This study is different from other studies done comparing these two surgical techniques. And that's because it was both a randomized controlled trial (RCT) and a long-term (five years) study. Randomized controlled trials place people in groups based on a computer generated list. That helps remove bias from the study and makes the results more reliable and valid.

The authors looked at a couple of other results in the long-term study that weren't available in the short-term. Symptom recurrence and need for a second surgery were two of those additional factors. Here again, the results were the same in the two groups. A small number of patients in both groups had to have a second (repeat) surgery because of persistent symptoms or symptoms that came back after surgery.

They found that patients who still had moderate to severe pain a year after the initial carpal tunnel release (no matter how it was done) did not get better. The reasons for the continued pain vary from patient to patient and aren't always clear.

Sometimes incomplete release of the transverse carpal tunnel ligament is the problem. In other cases, it may be injury to small sensory nerves to the skin. Scar tissue around the median nerve can tether (hold) it down and keep it from sliding and gliding as it should through the carpal tunnel.

The authors conclude that endoscopic carpal tunnel release is less invasive and thus has a small benefit when it comes to postoperative pain. But in regards to complication rate, return-to-work status, or function, the endoscopic approach was not superior to the open technique.
Isam Atroshi, MD, PhD, et al. Open Compared with 2-Portal Endoscopic Carpal Tunnel Release: A 5-Year Follow-Up of a Randomized Controlled Trial. In The Journal of Hand Surgery. February 2009. Vol. 34-A. No. 2. Pp. 266-272.