High Ulnar Nerve Palsy Research Articles

Supercharge end-to-side nerve transfer from anterior interosseous nerve to augment intrinsic recovery in high ulnar nerve injuries of varying magnitudes

High ulnar nerve injuries result in intrinsic muscle weakness and are inconvenient for patients. Moreover, conventional surgical techniques often fail to achieve satisfactory motor recovery. A potential reconstructive solution in the form of the supercharge end-to-side (SETS) anterior interosseous nerve (AIN) transfer method has emerged. Therefore, this study aims to compare surgical outcomes of patients with transected and in-continuity high ulnar nerve lesions following SETS AIN transfer. Between June 2015 and May 2023, patients with high ulnar palsy in the form of transection injuries or lesion-in-continuity were recruited. The assessment encompassed several objective results, including grip strength, key pinch strength, compound muscle action potential, sensory nerve action potential, and two-point discrimination tests. The muscle power of finger abduction and adduction was also recorded. Additionally, subjective questionnaires were utilized to collect data on patient-reported outcomes. Overall, the patients were followed up for up to 2 years. Patients with transected high ulnar nerve lesions exhibited worse baseline performance than those with lesion-in-continuity, including motor and sensory functions. However, they experienced greater motor improvement but less sensory recovery, resulting in comparable final motor outcomes in both groups. In contrast, the transection group showed worse sensory outcomes. Our findings suggest that SETS AIN transfer benefits patients with high ulnar nerve palsy, regardless of the lesion type. Nonetheless, improvements may be more pronounced in patients with transected lesions.

Restoration of the first dorsal interosseous muscle

Motor dysfunction of the 1st dorsal interosseous (DIO) muscle is typically observed in low and high ulnar nerve palsy. This causes weak thumb-index pinch, which can be disabling for the patient. Various reconstructive techniques have been described; however, the choice often depends on the surgeon’s experience, the presence of associated neurovascular and musculotendinous injuries, as well as the requirements of the palliative surgery schedule. Nerve transfers can be proposed when patients present early in the course of the disease. Tendon transfers are often a last resort when late presentation occurs. Tendon transfers must follow general principles: the insertion is made on the 1st DIO terminal tendon; the tension must be adjusted in a neutral position to avoid excessive tension, and immobilization is maintained for 4 weeks. Although many transfers are possible, the extensor pollicis brevis transfer is our preferred option. This donor does not require additional tendon grafting, has a direct line of pull close to that of the 1st DIO and is not often used for other reconstructive purposes.

End-to-Side Anterior Interosseous Nerve Transfer: A Valuable Alternative for Traumatic High Ulnar Nerve Palsy.

The prognosis of high ulnar nerve injury is poor despite nerve repair or grafting. Anterior interosseous nerve (AIN) transfers provide a satisfactory recovery. However, the efficacy of end-to-side (ETS) AIN transfer and optimal timing in Sunderland grade IV/V of high ulnar nerve injury is lacking. The goals were to compare the outcomes of high ulnar nerve injury managed with ETS AIN transfers with those managed with conventional procedures (nerve repair or graft only) and identify differences between early and delayed transfers. Patients with isolated high ulnar nerve injury (Sunderland grade IV/V) from 2010 to 2017 were recruited. Patients with conventional treatments and AIN transfers were designated as the control and AIN groups, respectively. Early transfer was defined as the AIN transfer performed within 8 weeks postinjury. Outcomes were measured and analyzed by the British Medical Research Council (BMRC) score, grip strength, and pinch strength. A total of 24 patients with high ulnar nerve injury (Sunderland grade IV/V) were included. There were 11 and 13 patients in the control and AIN groups, respectively. In univariate analysis, both early and delayed AIN transfers demonstrated significantly better motor recovery among BMRC score and strength of grip and pinch at 12 months (P < 0.05). No statistical significance was found between early and delayed transfer. In multivariate analysis, both early and delayed transfers were regarded as strong and independent factors for motor recovery of ulnar nerve. Compared with the control, early [odds ratio (OR), 1.83; P < 0.001] and delayed (OR, 1.59; P < 0.001) transfers showed significant improvement with regard to BMRC scores. The pinch strength in early (OR, 31.68; P < 0.001) and delayed (OR, 26.45; P < 0.001) transfers was also significantly better. The ETS AIN transfer, in either early or delayed fashion, significantly improved intrinsic motor recovery in high ulnar nerve injuries classified as Sunderland grade IV/V. The early transfer group demonstrated a trend toward better functional recovery with less downtime.

Supinator to ulnar nerve transfer via in situ anterior interosseous nerve bridge to restore intrinsic muscle function in combined proximal median and ulnar nerve injury: a novel cadaveric study

BackgroundIn cases of high ulnar nerve palsy, result of nerve repair in term of intrinsic muscle recovery is unsatisfactory. Distal nerve transfer can diminish the regeneration time and improve the results. But, there was no perfect distal nerve transfer for restoring intrinsic hand function in combined proximal median and ulnar nerve injuries. This cadaveric study aims to evaluate the possibility and feasibility of supinator nerve transfer to motor branch of ulnar nerve (MUN). MethodsTen cadaveric upper limbs dissected to identify the location of the supinator branch, anterior interosseous nerve (AIN), and MUN. The AIN was cut from its origin and transferred to the supinator branches. Also, the AIN was distally cut and transferred to the MUN. After nerve coaptation, surface area, fascicle count, and axon number were determined by histologic methods. ResultsIn all limbs, the proximal and distal stumps of AIN reached the supinator branch and the MUN without tension, respectively. The mean of axon number in the supinator, proximal stump of AIN, distal stump of AIN and MUN branches were 32,426, 45,542, 25,288, and 35,426, respectively. ConclusionsThis study showed that transfer of the supinator branches to the MUN is possible via the in situ AIN bridge. The axon count data showed a favorable match between the supinator branches, AIN, and MUN. Therefore, it is suggested that this technique can be useful for patients with combined high median and ulnar nerve injuries.

Results of Dynamic Claw Correction in Ulnar nerve Palsy

Normal hand function is a balance between the extrinsic-intrinsic and extensor-flexor group of musculature. Although individually the intrinsics are very small muscles, collectively they contribute about 50% of grip strength. Total 19 patents with claw deformity were corrected by 4 different techniques. 11 claws were due to high ulnar nerve palsy and 8 were due to low palsy. Result was excellent in 9 (47.36%), good in 7(36.84%), fair in 2(10.52%) and poor in 1(05.26%) patient. Zancolli’s Lasso was the most common procedure used for correction of claw deformity. 1(05.26%) patient developed swan neck deformity treated by FDS 4 tail procedure of low lesion group and final result was fair, another 1 (05.26%) patient developed contracture of the PIP joint. Though exact biomechanical correction of claw is complicated yet function of the hand can be improved with different techniques of tendon transfer.DOI: http://dx.doi.org/10.3329/bdjps.v3i1.15000 Bangladesh Journal of Plastic Surgery 2012, 3(1): 13-18

Bilateral temporoparietal fascial free flaps for reconstruction of bilateral hand defects: A report of two cases

Bilateral temporoparietal fascial free flaps were used for reconstruction of bilateral hand defects in two male patients. A 42-year-old man sustained crushed injury to both hands with avulsion defects and exposed bones and tendons. The two separate procedures were performed under general anesthesia. The temporoparietal fascial free flap was skin grafted on the ward on the following day after the operation. The other patient was a 61-year-old leprosy patient who had bilateral high ulnar nerve palsy for 28 years. One simultaneous procedure was performed under local anesthesia for harvesting the temporoparietal fascial free flaps and under brachial block for preparation of the recipient sites. The free flaps were used for augmentation of the atrophic first web spaces. The postoperative results of the two cases were satisfactory. The functions of both hands were restored with normal gliding mechanism of the tendons in the first case, and permanent correction of the atrophic web spaces was demonstrated in the second case. The temporoparietal fascial free flap is an ideal flap for coverage of hand defects as well as augmentation of first web space atrophy.

Intrinsic Muscle Contribution to the Metacarpophalangeal Joint Flexion Moment of the Middle, Ring, and Small Fingers

To analyze the relative contribution of the intrinsic muscles to the flexion moment potential of the metacarpophalangeal (MCP) joints of the middle, ring, and small fingers and to calculate the moment potential loss occurring with deep motor branch, low, or high ulnar nerve palsy or low median nerve palsy. Eleven fresh cadaver hands were used. A small wire sutured to each tendon was connected to an excursion transducer containing a constant-tension spring. The tendon excursion and the MCP joint rotation were measured simultaneously during 10 to 16 cycles of passive flexion/extension cyclic motion. The moment arm was calculated from the tendon excursion-joint rotation curve as the derivative of the curve. The flexion moment potential was calculated by multiplying the moment arm with the known tension fractions of the muscles. When the MCP joint was at 0 degrees of flexion the relative moment potential contributions of the intrinsic muscles to MCP joint flexion were 8%, 13%, and 28% in the middle, ring, and small fingers, respectively. Moment potential losses were 7%, 13%, and 6% in the middle, ring, and small fingers, respectively, in deep motor branch ulnar nerve palsy. In low ulnar nerve palsy the losses were 7%, 13%, and 28%, respectively. In high ulnar nerve palsy they were 7%, 64%, and 82%, respectively. Low median nerve palsy, however, resulted in a moment potential loss at the middle finger MCP joint of less than 2%. The relative contribution of the intrinsic muscles to the total flexion moment at the MCP joint was different for each finger. The small finger had a large intrinsic contribution, primarily because of the larger moment arms of the hypothenar muscles.

Ulnar Intrinsic Anatomy and Dysfunction

Normal hand function is a balance between the extrinsic and intrinsic musculature. Although individually the intrinsics are small muscles in diameter, collectively they represent a large muscle that contributes approximately 50% of grip strength. Dysfunction of the intrinsics consequently leads to impaired grip and pinch strength as well recognized deformities. Low ulnar nerve palsy preserves ulnar innervated extrinsics resulting in sensory loss, digital clawing, thumb deformity, abduction of the small finger, and asynchronous finger motion. High ulnar nerve palsy is characterized by the above plus paralysis of the ulnar profundi and the flexor carpi ulnaris. Understanding the normal anatomy allows the clinician to identify the site of the lesion and plan appropriate surgical intervention. This article revisits the classic work of Richard J. Smith on ulnar nerve palsy with contemporary perspective.

High Ulnar Nerve Palsy by the Arcade of Struthers in the Elbow: Report of 2 Cases

The arcade of Struthers has been described as a possible cause of ulnar nerve compression in the elbow. This paper reports two cases of ulnar neuropathy caused by the arcade of Struthers. These observations demonstrated the importance of evaluation of the arcade of Struthers in atypical high ulnar nerve palsy.

High Ulnar Nerve Palsy Caused by the Arcade of Struthers

A case of ulnar nerve entrapment neuropathy caused by the arcade of Struthers is reported. Nerve conduction studies showed a complete block and surgical decompression was successful.