Background:Carpal tunnel syndrome is the most common compressive neuropathy of the upper extremity. Standard open carpal tunnel release is the gold standard treatment; however, that procedure can result in scar tenderness and pillar pain. Minimally invasive surgery is less likely to cause these post-surgical complications. The authors invented a newly-designed instrument that facilitates easier placement of the instrument into the carpal tunnel, and that has a more secure holding piece to stabilize the instrument during division of the ligament.

Objective: To investigate the efficacy of our newly-designed instrument using the limited skin incision technique in cadaver model, and to identify potential risks of injury to nearby important structures.

Materials and Methods: Forty unembalmed cadaveric wrists without history or sign of previous injury or surgery were used for carpal tunnel release procedure using limited longitudinal skin incision at palm. To assess the completeness of transverse carpal ligament release, a proximally-extended skin incision was made to evaluate the released ligament. Median nerve, recurrent motor branch of median nerve, palmar cutaneous branch of median nerve, flexor tendons in carpal tunnel, and superficial palmar arterial arch were dissected to identify evidence of injury.

Results: All transverse carpal ligaments of 40 cadaveric wrists were completely released with preservation of fascial coverage between the thenar and hypothenar muscles. All surrounding important structures were identified without evidence of injury.

Conclusion: This newly designed instrument for carpal tunnel release demonstrated precision function and efficacy without injury to surrounding structures, and with preservation of fascial coverage above the ligament. Further investigation for application in clinical use is needed to confirm the safety and efficacy of this newly-designed instrument.

 Keywords: Carpal tunnel release, instrument, efficacy, minimally-invasive surgery, cadaveric study