Pick-up test: an indication for opponensplasty in patients with severe carpal tunnel syndrome

Causes of Iatrogenic Median Nerve Injury after Endoscopic Carpal Tunnel Release

Background: Endoscopic carpal tunnel release (ECTR) is a less invasive procedure but has a higher risk of complications. We analysed ECTR cases dividing them into three periods according to a single surgeon's experience when the ECTR was performed: the initial, midterm and late period. Cases of iatrogenically induced median nerve injuries that occurred after ECTR were then noted and evaluated. Methods: We reviewed 195 ECTRs done with the 2-portal technique and divided the patients into three groups according to periods of when ECTR was done. The indications for ECTR surgery were limited to severe CTS cases. These groups of patients were similar in terms of age, duration of disease, electrophysiological study results and severity of the disease. The patients were evaluated for median neuropathy pre- and postoperatively using Semmes-Weinstein monofilament test (SWT), Disabilities of the arm, shoulder and hand (DASH) Score, Coin-flip test (CFT), postoperative paraesthesias and complications, such as pillar pain, and so on. Electrophysiological evaluation was performed only preoperatively. Results: Postoperative median nerve recovery was overall good. Normal recovery was noted in 181 cases (93%). SWT, DASH and CFT were all significantly improved upon follow-up in all three groups. In terms of iatrogenic neuropathy, median nerve palsy worsened (including those transiently worsened) after ECTR in 11 cases (5.6%), even in the later period. The sensory disturbance was equally worsening from the radial to the ulnar side. Conclusions: The fact that there were neurologically worsened cases even in the later period, when the operator is higher skilled in the technique, suggests that the surgical technique itself may be the one posing higher risk than the level of surgical skill. The most likely causes of aggravated nerve palsy were a direct injury by cannula insertion at the proximal portal, or additional median nerve compression during cannula insertion into the carpal tunnel. Level of Evidence: Level IV (Therapeutic).

Minimally Invasive Palmaris Longus Abductorplasty for Severe Carpal Tunnel Syndrome

Camitz abductorplasty is the most commonly used tendon transfer in patients with severe carpal tunnel syndrome with significant muscle wasting and loss of opposition. This procedure requires a long incision in the palm to harvest a strip of palmar aponeurosis to lengthen the palmaris longus tendon, allowing it to reach the abductor pollicis brevis insertion. Several complications have been attributed to this extensive dissection in the palm. We describe a minimally invasive palmaris longus abductorplasty using a strip of free flexor carpi radialis tendon graft to achieve the necessary length. This can be done together with carpal tunnel release in patients with severe carpal tunnel syndrome.

The relationship between preoperative needle electromyography findings and muscle power restoration after surgery in severe carpal tunnel syndrome patients

PURPOSE

Needle electromyography provides essential information about the functional aspects of the muscle. But little attention has been given in the literature to needle electromyography examinations in carpal tunnel syndrome. We examined the relationship between preoperative needle electromyography findings and functional recovery of the abductor pollicis brevis (APB) muscle in severe carpal tunnel syndrome patients.

METHODS

The subjects of this study were 49 patients, 58 hands, who fit the following 5 criteria: (1) idiopathic carpal tunnel syndrome; (2) pre-op MMT grade of the APB muscle was M0 or M1; (3) APB-CMAP (compound muscle action potential) was not evoked in a median nerve conduction study; (4) needle electromyography of the APB muscle had been done; (5) underwent carpal tunnel release only. The patients were divided into two groups according to the results of pre-op needle electromyography: voluntary motor unit potential of the APB muscle was evoked [MUP(+) group]or not [MUP(-) group]. We evaluated APB muscle strength at one year after surgery, and patient satisfaction and functional evaluations (CTSI-FS) at more than one year after.

RESULTS

The APB muscle recovery rate to M3 or higher was 100% in the MUP(+) group, and 57% in the MUP(-) group. Patient satisfaction was also high and functional recovery was sufficient in the MUP(+) group. No patients requested a second opponensplasty.

CONCLUSION

Our findings suggest that post-op restoration of thumb function relates to whether or not the MUP ofthe APB muscle is evoked. Single-stage opponensplasty may be unnecessary if the MUP of the APB muscle is; evoked. Needle electromyography is therefore useful in consideration for opponensplasty.

LEVEL OF EVIDENCE

Level Ⅲ, case-control study.

The Camitz transfer and its modifications: a review

The Camitz procedure involves transfer of the insertion of the palmaris longus tendon with a strip of the palmar aponeurosis to the insertion of abductor pollicis brevis in order to improve thumb opposition, and is usually done when severe carpal tunnel syndrome results in complete wasting of the thenar muscles. We carried out a systematic review of the published reports of this procedure. Analysis of available outcome data showed improvement in overall hand function in 86-100% of patients undergoing the original Camitz procedure. Several modifications of the original Camitz transfer have been described, with most focusing on the incorporation and placement of pulleys. All studies are limited by their small sample sizes. Overall, there is a lack of studies comparing the Camitz transfer with other opponensplasty techniques and comparing the various modifications of the original procedure.

LEVEL OF EVIDENCE

IV.

Opponoplasty without postoperative immobilization

Opponoplasty using tendon transfer is a useful reconstructive procedure that restores lost thenar muscle function. Tendon transfers, however, require postoperative immobilization periods of up to four weeks before the sutured tendons reach required strength. We developed an opponoplasty procedure using α-TCP (alpha-tricalcium phosphate) cement that does not require postoperative immobilization and was applied to nine hands out of nine cases. The procedure is performed under local anesthesia without a pneumatic tourniquet and on an outpatient basis. In this procedure, the flexor digitorum superficialis of the ring finger is used as the donor tendon and the palmaris longus tendon is used as a dynamic pulley. The distal end of the transferred tendon is anchored to the inside of a newly formed bone hole in the thumb's proximal phalanx using α-TCP cement. Our opponoplasty procedure was uneventful postoperatively and produced satisfactory results in all nine cases. The α-TCP cement procedure shows potential for other tendon transfer applications.