Reducing neurologic and vascular complications of endoscopic carpal tunnel release using a modified chow technique.
OBJECTIVE
To reduce the rate of median nerve injury occurring during Chow's original 2-portal technique, we developed a modified procedure. The surgical technique was introduced, and the results were evaluated with regard to the clinical findings, nerve conduction studies, and Disabilities of the Arm, Shoulder, and Hand (DASH) score.


METHODS
We analyzed 119 hands of 119 patients with idiopathic carpal tunnel syndrome who underwent our procedure, wherein a cannula assembly was inserted after a partial division of both distal and proximal parts of the transverse carpal ligament through the entry and exit portals. Postoperative examinations, including evaluation of numbness, grip strength, pinch strength, tenderness over and around the wounds, and nerve conduction studies, were performed at 1 month (n = 119), 3 months (n = 119), 6 months (n = 102), and 12 months (n = 39). The DASH score was also evaluated preoperatively and at 3, 6, or 12 months postoperatively. The rate of structural damage to the median nerve, the tendon, and the artery was calculated.


RESULTS
The patients resumed their daily activities or work by 13 days postoperatively. Tenderness around the wounds was detected in 66% of patients by 3 months postoperatively. Numbness disappeared or decreased in 99% of patients by 6 months postoperatively. The DASH score was available for 82 patients, and it improved from 28.2 to 18.3 points postoperatively. Nerve conduction studies indicated a significant decrease in motor distal latency postoperatively. Temporal worsening of median nerve function was observed in 2 patients; however, no structural damage to the nerve, tendon, or artery was observed.


CONCLUSIONS
We found no injury to the tendon or artery and no laceration to the nerve in all 119 patients. However, temporal worsening of median nerve function was observed in 2 patients.


METHODS
Level IV, therapeutic case series.
Department of Orthopaedic Surgery, Suwa Red Cross Hospital, Suwa, Japan.
Shigeharu
S
Uchiyama
Takashi
T
Yasutomi
Takashi
T
Fukuzawa
Hiroyuki
H
Nakagawa
Mikio
M
Kamimura
Hiroyuki
H
Kato
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001182:Arthroscopy / Q000009:adverse effects / Q000379:methods*; D002349:Carpal Tunnel Syndrome / Q000601:surgery*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006987:Hypesthesia / Q000209:etiology / Q000503:physiopathology; D008297:Male; D008475:Median Nerve / Q000293:injuries* / Q000503:physiopathology; D008875:Middle Aged; D009431:Neural Conduction; D010149:Postoperative Pain / Q000503:physiopathology; D013997:Time Factors; D014652:Vascular Diseases / Q000209:etiology / Q000517:prevention & control*; D014947:Wounds and Injuries / Q000209:etiology / Q000503:physiopathology / Q000517:prevention & control