Carpal tunnel surgery

Scars from carpal tunnel release surgery. Two different techniques were used. The left scar is 6 weeks old, the right scar is 2 weeks old. Also note the muscular atrophy of the thenar eminence in the left hand, a common sign of advanced CTS

Carpal Tunnel Syndrome Operation

Release of the transverse carpal ligament is known as "carpal tunnel release" surgery. It is recommended when there is static (constant, not just intermittent) numbness, muscle weakness, or atrophy, and when night-splinting no longer controls intermittent symptoms. In general, milder cases can be controlled for months to years, but severe cases are unrelenting symptomatically and are likely to result in surgical treatment.

Procedure

In carpal tunnel release surgery, the goal is to divide the transverse carpal ligament in two. This is a wide ligament that runs across the hand, from the scaphoid bone to the hamate bone and pisiform. It forms the roof of the carpal tunnel, and when the surgeon cuts across it (i.e., in a line with the ring finger) it no longer presses down on the nerve inside, relieving the pressure.

There are several carpal tunnel release surgery variations: Each surgeon has differences of preference based on his or her personal beliefs and experience. All techniques have several things in common, involving briefoutpatient procedures, palm or wrist incision(s), and cutting of the transverse carpal ligament.

The two major types of surgery are open carpal tunnel release and endoscopic carpal tunnel release. Most surgeons historically have performed the open procedure, widely considered to be the gold standard. However, since the 1990s, a growing number of surgeons now offer endoscopic carpal tunnel release.

Open surgery involves an incision on the palm about an inch or two in length. Through this incision, the skin and subcutaneous tissue is divided, followed by the palmar fascia, and ultimately the transverse carpal ligament.

Endoscopic carpal tunnel release

Endoscopic techniques or endoscopic carpal tunnel release involve one or two smaller incisions (less than half inch each) through which instrumentation is introduced including a synovial elevator, probes, knives, and an endoscope used to visualize the underside of the transverse carpal ligament. The endoscopic methods do not divide the subcutaneous tissues or the palmar fascia to the same degree as the open method does. Many studies have been done to determine whether perceived benefits of a limited endoscopic or arthroscopic release are significant. Brown et al. conducted a prospective, randomized, multi-center study and found no significant differences between the two groups with regard to secondary quantitative outcome measurements.However, the open technique resulted in more tenderness of the scar than the endoscopic method. A prospective randomized study done in 2002 by Trumble revealed that good clinical outcomes and patient satisfaction are achieved more quickly with the endoscopic method. Single-portal endoscopic surgery is a safe and effective method of treating carpal tunnel syndrome. There was no significant difference in the rate of complications or the cost of surgery between the two groups. However, the open technique caused greater scar tenderness during the first three months after surgery, and a longer time before the patients could return to work. In addition, in patients without workers compensation issues, the single-incision endoscopic carpal tunnel release led to less palmar tenderness and a quicker return to work compared to the two-incision endoscopic carpal tunnel release (Palmer DH, Paulson JC, Lane-Larsen CL, Peulen VK, Olson JD: Endoscopic carpal tunnel release: a comparison of two techniques with open release. Arthroscopy 9:498-508, 1993.)

Many surgeons have embraced limited incision methods. It is considered to be the procedure of choice for many of these surgeons with respect to idiopathic carpal tunnel syndrome. Supporting this are the results of some of the previously mentioned series that cite no difference in the rate of complications for either method of surgery. Thus, there has been broad support for either surgical procedure using a variety of devices or incisions. The primary goal of any carpal tunnel release surgery is to divide the transverse carpal ligament and the distal aspect of the volar ante brachial fascia, thereby decompressing the median nerve. Despite these views, some surgeons have suggested that in their own hands endoscopic carpal tunnel release has been associated with a higher incidence of median nerve injury, and for this reason it has been abandoned at several centers in the United States. At the 2007 meeting of the American Society for Surgery of the Hand, a former advocate of endoscopic carpal tunnel release, Thomas J. Fischer, MD, retracted his advocacy of the technique, based on his own personal assessment that the benefit of the procedure (slightly faster recovery) did not outweigh the risk of injury to the median nerve. Contrary to this one or any one opinion of any individual surgeon it has been shown that while there is a learning curve for a hand surgeon who begins to use an endoscopic technique to release the transverse carpal ligament no significant safety issues or morbididty associated with the endoscopic method exist. The use of endoscopic carpal tunnel release has continued to spread around the world and clinical and nerve electrophysiological states are significantly improved at the long-term follow-up after endoscopic carpal tunnel release. A meta-analysis supports the conclusion that endoscopic carpal tunnel release is favored over the open carpal tunnel release in terms of a reduction in scar tenderness and increase in grip and pinch strength at a 12-week follow-up

Efficacy

Surgery to correct carpal tunnel syndrome has a high success rate. Up to 90% of patients were able to return to their same jobs after surgery. In general, endoscopic techniques are as effective as traditional open carpal surgeries, though the faster recovery time typically noted in endoscopic procedures is felt by some to possibly be offset by higher complication rates. Success is greatest in patients with the most typical symptoms. The most common cause of failure is incorrect diagnosis, and it should be noted that this surgery will only mitigate carpal tunnel syndrome, and will not relieve symptoms with alternative causes. Recurrence is rare, and apparent recurrence usually results from a misdiagnosis of another problem. Complications can occur, but serious ones are infrequent to rare.

Carpal tunnel surgery is usually performed by a hand surgeon, orthopaedic surgeon, orplastic surgeon. Some neurosurgeons and general surgeons also perform the procedure.

Experimental procedures

Balloon carpal tunnelplasty is an experimental technique that uses a minimally invasive balloon catheter director to access the carpal tunnel. As with a traditional tissue elevator/expander, balloon carpal tunnelplasty elevates the carpal ligament, increasing the space in the carpal tunnel. As an experiment it has been described but there are no peer reviewed series available in the current hand surgical literature that review or comment upon the procedure. The technique is performed through a one-centimeter incision at the distal wrist crease. It is monitored and expansion is confirmed by direct or endoscopic visualization. The technique's secondary goals are to avoid to incision in the palm of the hand, to avoid cutting of the transverse carpal ligament, and to maintain the biomechanics of the hand.