Preserving the ulnar bursa does not improve carpal tunnel surgery outcomes

Both groups reported similar amounts of scar pain, with six patients in each group stating the scar was painful or puffy.

Preserving the ulnar bursa within the carpal tunnel does not affect the outcome of carpal tunnel release surgery, results of a prospective study suggest.

"We failed to demonstrate any benefit from careful preservation of the ulnar bursa around the median nerve, although doing so was associated with a slightly lower prevalence of suspected wound infection or inflammation," the authors said. "We recommend incision of the ulnar bursa during open carpal tunnel decompression to allow complete visualization of the median nerve and the carpal tunnel contents."

Daren P. Forward, MRCS, and colleagues at Queen's Medical Center in Nottingham, England, conducted the randomized study to determine whether preserving the ulnar bursa improved carpal tunnel decompression outcomes. Surgeons preserved the ulnar bursa in 53 patients and divided it in 58 patients.

The results are published in the American edition of the Journal of Bone and Joint Surgery.

Postoperatively, both groups had similar grip strengths, averaging 79% of the preoperative strength for ulnar bursa-preserved patients and 82% for ulnar bursa-divided patients, according to the study.

For both groups, thumb key pinch strength also significantly decreased from preoperative levels, but there was no significant difference between groups postoperatively. Also, neither group had a significant decrease in thumb tip pinch following surgery, again with no significant differences between groups.

Both groups reported similar amounts of scar pain, with six patients in each group stating that the scar was painful or puffy. "Ordinal regression analysis ... confirmed that preservation or division of the ulnar bursa had no influence on scar tenderness," the authors said.

At 8 to 9 weeks follow-up, self-rated outcomes had significantly improved for both groups, again with no significant differences between groups, according to the study.

One patient with a preserved ulnar bursa was diagnosed with infection, and seven patients with divided ulnar bursae were suspected of infection, six of whom were treated with antibiotics. "This patient-reported infection rate is higher than one would expect, but it must be noted that no patient in either group returned to the hospital for treatment of the suspected infection," the authors said.

For more information:
Forward DP, Singh AK, Lawrence TM, et al. Preservation of the ulnar bursa within the carpal tunnel: Does it improve the outcome of carpal tunnel surgery? A randomized, controlled trial. J Bone Joint Surg Am. 2006;88-A:2432-2438.