A cut throat: a case of C5-C8 brachial plexus root transection providing evidence of T1 innervation of thumb and finger extensors

The T1 nerve root is not routinely thought of as innervating the extensors of the thumb and fingers. Work by Bertelli and Ghizoni proposed that the pattern of brachial plexus paralysis with intact hand function and thumb and finger extensors traditionally attributed to C5/6/7 root injury is in fact a C5/6/7/8 injury, with only T1 remaining intact - a 'T1 hand'. This case presents a 19-year-old male who was stabbed in the neck; exploratory surgery determined complete transection of the brachial plexus, with only the T1 nerve root remaining intact. Clinical examination demonstrated grade M4 pronation (with pronator quadratus), wrist extension (with extensor carpi ulnaris), thumb and finger extension (with extensor policis longus and brevis, extensor digitorum communis and extensor index proprius), wrist flexion (with palmaris longus), finger flexion (with flexor digitorum superficialis and profundus), thumb flexion (with flexor policis longus), and thenar and hypothenar muscles. Extensor carpi radialis longus and brevis, flexor carpi radialis and flexor carpi ulnaris were paralyzed. Triceps scored M2. This case provides unequivocal evidence that the T1 root provides significant innervation to the extrinsic thumb and finger extensors.

Reconstructing Pinch Strength after Ulnar Nerve Injury by Transferring the Opponens Pollicis Motor Branch

BACKGROUND

With ulnar nerve injuries, paralysis of the first dorsal interosseous(FDI) and adductor pollicis muscle weakens the patient's pinch. In the palm, we transferred the opponens pollicis motor branch (Opp) to the deep terminal division of the ulnar nerve (DTDUN) for pinch reconstruction.

METHODS

Sixteen patients with ulnar nerve injuries around the elbow underwent reconstruction and were followed post-operatively for a minimum of 14 months. Their mean age was 41 years (SD ± 15), and the mean interval between injury and surgery was 134 days (SD ±126, range: 2-390). Pre- and postoperatively grasp, key and subterminal key-pinch strength were measured using dynamometers.

RESULTS

Reinnervation of the FDI was observed in 15 of the 16 patients. Mean grasp strength improved from 15.5kg (SD ± 8.5kg) pre-operatively to 24kg (SD ± 10kg) postoperatively, achieving 57% (SD ± 16%) contralateral hand strength. Preoperatively, terminal key pinch averaged 3kg (±1kg), which improved postoperatively to 5.5kg (SD ± 2kg), achieving 71% (±24%) the strength measured contralaterally. Pre- to post-operatively, subterminal key-pinch force increased from zero to 2.4kg (SD ± 1.3kg) achieving 61% (SD ± 27%) that of the unaffected side. Patients who underwent surgery within six months of their injury showed a mean subterminal key pinch strength recovery of 63% (SD ± 27) of the normal side, while those who underwent surgery between seven and 13 months after injury showed a mean subterminal key pinch strength recovery of 51% (SD ± 29).

CONCLUSIONS

Transferring the Opp to the DTDUN improved pinch and grasp strength without jeopardizing thumb function.

Spinal Cord Injury: Epidemiology, Spontaneous Recovery, and Hand Therapy for the Reconstructive Hand Surgeon

People with spinal cord injury (SCI) prioritize hand function above all else as a reconstructive goal, yet remain a markedly undertreated population by hand surgeons. This review article provides an overview of the epidemiology of SCI and the unmet clinical need of these patients. Further, this article outlines the natural history of SCI, including the expected spontaneous recovery over time and the expectations of hand function when treated with hand therapy alone. This review aims to equip reconstructive hand surgeons with a sound understanding of the basic principles of SCI and recovery and provide a rationale for when to intervene with surgery. In the last decade, this field has changed dramatically with the advent of reliable nerve transfers, making referral and surgical intervention time-sensitive. Therefore this review aims to highlight the expectations from hand therapy alone in this group, the urgent need for early referral to allow nerve transfer options to be viable, and the strategies for overcoming the barriers to these referrals. This offers the opportunity for surgeons to expand their tetraplegia practices while maximizing the considerable contributions to the hand function and quality of life of these patients.

Two clinical tests assessing long thoracic nerve function to determine C5 and C6 root graft eligibility in patients with brachial plexus injury

OBJECTIVE

Identifying roots available for grafting is of paramount importance prior to reconstructing complex injuries involving the brachial plexus. This is traditionally achieved by combining input from both clinical examinations and imaging studies. In this paper, the authors describe and evaluate two new clinical tests to study long thoracic nerve function and, consequently, to predict the status of the C5 and C6 roots after global brachial plexus injuries.

METHODS

From March 2020 to December 2020, in 41 patients undergoing brachial plexus repair, preoperative clinical assessments were performed using modified C5 and C6 protraction tests, C5 and C6 Tinel's signs, and MRI findings to predict whether graft-eligible C5 and C6 roots would be identified intraoperatively. Findings from these three assessments were then combined in a logistic regression model to predict graft eligibility, with overall predictive accuracies calculated as areas under receiver operating characteristic curves.

RESULTS

In the 41 patients, the pretest probability of C5 root availability for grafting was 85% but increased to 92% with a positive C5 protraction test and to 100% when that finding was combined with a positive C5 Tinel's sign and favorable MRI findings. The pretest probability of C6 root availability was 40%, which increased to 84% after a positive C6 protraction test and to 93% when the protraction test result concurred with Tinel's test and MRI findings.

CONCLUSIONS

Combining observations of the protraction tests with Tinel's sign and MRI findings accurately predicts C5 and C6 root graft eligibility.

Selective transfer of nerve to supinator to restore digital extension in central cord syndrome: An anatomical study and a case report

BACKGROUND

Nerve transfers are increasingly used to restore upper extremity function in patients with spinal cord injury. However, the role of nerve transfers for central cord syndrome is still being established. The purpose of this study is to report the anatomical feasibility and clinical use of nerve transfer of supinator motor branches (NS) to restore finger extension in a central cord syndrome patient.

MATERIALS AND METHODS

The posterior interosseous nerve (PIN), its superficial division, and branches were dissected in 14 fresh cadavers, with a mean age of 65 (58-79). Measurements included number and length of branches of donor and recipient, diameters, regeneration distance from coaptation site to motor entry point and axonal counts. A NS transfer to extensor carpi ulnaris (ECU), extensor digiti quinti (EDQ) and extensor digitorum communis (EDC) was performed in a 28-year-old patient, with central cord syndrome after a motorcycle accident, who did not recover active finger extension at 10 months post injury.

RESULTS

The PIN consistently divided into a deep and superficial branch between 1.5 cm proximal to, and 2 cm distal to the distal boundary of the supinator. The superficial branch provided a first common branch to the ECU and EDQ. In 12/14 dissections, the EDC was innervated by a 4 cm long branch that entered the muscle on its radial deep surface. In all cases, the superficial branch of the PIN could be separated in a retrograde fashion from the PIN and coapted with NS. The mean myelinated fiber count in nerve to EDC was 401 ± 190 compared to 398 ± 75 in the NS. At 48 months after surgery, with the wrist at neutral, the patient recovered full metacarpophalangeal extension scoring M4. Supination was preserved with the elbow extended or flexed.

CONCLUSIONS

Restoration of finger extension in central cord syndrome is possible with a selective transfer of the NS to EDC, and is anatomically feasible with a short regeneration distance and favorable axonal count ratio.

Effectiveness of Distal Nerve Transfers for Claw Correction With Proximal Ulnar Nerve Lesions

PURPOSE

To evaluate claw deformity correction following anterior interosseous nerve (AIN) end-to-end transfer to the deep motor branch of the ulnar nerve (DMBUN) in high ulnar nerve injuries.

METHODS

Eleven patients were retrospectively evaluated for metacarpophalangeal joint hyperextension and proximal interphalangeal joint extension lag in the fourth and fifth digits following ulnar nerve injury adjacent or proximal to the elbow, who underwent AIN end-to-end transfer to the DMBUN.

RESULTS

Patients underwent surgery an average of 5 months following injury (range, 2-9 months) and were followed for an average of 19 months after surgery (range, 12-30 months). At the last follow-up, clawing was observed in all patients, with proximal interphalangeal joint extension lag averaging 46.8° (SD, ±20°) in the fourth digit and 57.7° (SD, ±12°) in the little finger.

CONCLUSIONS

None of our patients experienced claw correction after AIN end-to-end transfer to the DMBUN.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Studying nerve transfers: Searching for a consensus in nerve axons count

Axonal count is the base for efficient nerve transfer; despite its capital importance, few studies have been published on human material, most research approaches being performed on experimental animal models of nerve injury. Thus, standard analysis methods are still lacking. Quantitative data obtained have to be reproducible and comparable with published data by other research groups. To share results with the scientific community, the standardization of quantitative analysis is a fundamental step. For this purpose, the experiences of the Italian, Austrian, German, Greek, and Iberian-Latin American groups have been compared with each other and with the existing literature to reach a consensus in the fiber count and draw up a protocol that can make future studies from different centers comparable. The search for a standardization of the methodology was aimed to reduce all the factors that are associated with an increase in the variability of the results. All the preferential methods to be used have been suggested. On the other hand, alternative methods and different methods have been identified to achieve the same goal, which in our experience are completely comparable; therefore, they can be used indifferently by the different centers according to their experience and availability.

Subterminal key pinch dynamometry: a new method to quantify strength deficit in ulnar nerve paralysis

Precise pre- and postoperative assessments are fundamental to recording the quality of recovery after ulnar nerve repair. Because of its imprecision, manual muscle testing is being replaced by dynamometry to measure grasping and key-pinch strengths. However, both grasping and key pinch are dependent not only on the ulnar nerve but also the median and radial nerves. We propose to measure strength using a new sort of pinch, called the 'subterminal key pinch'. Strength was measured using a commercially available pinch meter. Patients applied pressure on the dynamometer with the interphalangeal joint of the thumb, maintaining the joint in extension to avoid enhancement of strength by the flexor pollicis longus. We examined 17 patients before ulnar nerve repair. Preoperatively, grasping strength was 46% of normal, while key pinch was 58%, pinch-to-zoom strength was 26% and subterminal key pinch only 7%. Subterminal key pinch was the most affected pinch with a strength deficit of over 90%.Level of evidence: IV.

Transfer of the Distal Anterior Interosseous Nerve for Thumb Motion Reconstruction in Radial Nerve Paralysis

PURPOSE

With nerve or tendon surgery, the results of thumb reconstruction to treat radial nerve paralysis are suboptimal. The goals of this study were to describe the anatomy of the deep branch of the posterior interosseous nerve (PIN) to the thumb extensor muscles (DBPIN), and to report the clinical results of transferring the distal anterior interosseous nerve (DAIN) to the DBPIN.

METHODS

The PIN was dissected in 12 fresh upper limbs. Myelinated nerve fibers in the DBPIN and DAIN were counted. Five patients with radial nerve paralysis underwent transfer of the motor branch to the flexor carpi radialis to the PIN and a motor branch of the pronator teres to the extensor carpi radialis brevis. In addition, these patients had selective reconstruction of thumb motion by transferring the DAIN to the DBPIN, through either a combined volar and dorsal approach (n = 2) or a single dorsal approach (n = 3) with division of the interosseous membrane.

RESULTS

At the origin of the abductor pollicis longus, the DBPIN divided into a lateral branch that innervated the abductor pollicis longus and extensor pollicis brevis, and a medial branch that innervated the extensor pollicis longus and extensor index proprius. The number of myelinated nerve fibers in the DAIN corresponded to 65% of that of the DBPIN. In each of the 5 patients, full thumb motion at the trapeziometacarpal joint was restored with no, or minimal, extension lag at the metacarpophalangeal (MCP) joint.

CONCLUSIONS

The anatomy of the DBPIN is predictable. Transferring the DAIN to the DBPIN is feasible through a single dorsal approach, allowing full recovery of thumb motion.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic V.

Nerve Versus Tendon Transfer for Radial Nerve Paralysis Reconstruction

PURPOSE

With radial nerve lesions, the results of nerve transfers and how they objectively compare with the outcomes of tendon transfers remain unstudied. We compared the results after nerve transfer in patients with less than 12 months since radial nerve injury with the results after tendon transfer in patients not eligible for nerve surgery because of longstanding paralysis (minimum of 15 months).

METHODS

In 14 patients with radial nerve lesions incurred less than 12 months previously, we transferred the anterior interosseous nerve to the nerve of the extensor carpi radialis brevis (ECRB), while the nerve to the flexor carpi radialis was transferred to the posterior interosseous nerve. In 13 patients with lesions of longer duration, we transferred the pronator teres tendon to the ECRB, the flexor carpi ulnaris tendon to the extensor digitorum communis, and the palmaris longus to the rerouted extensor pollicis longus (EPL) tendon. At a final evaluation, we measured passive and active range of motion (ROM) of the wrist, finger, and thumb and grasp strength.

RESULTS

In a comparison of wrist flexion-extension ROM and grasp strength, we observed better recovery in the nerve transfer than in the tendon transfer group. In the tendon transfer group, we observed limitations in wrist flexion in 9 of the 13 patients and permanent radial deviation in 5. Half of the patients in the tendon transfer group needed to flex their wrist to fully extend their fingers, whereas finger extension was possible with the wrist either extended or at neutral in all patients following nerve transfer. After nerve transfer, extension at the first carpometacarpal joint was restored in 11 of the 14 patients, whereas this occurred in just 4 of the 13 patients following tendon transfer. In both groups, we observed a 30° lag in thumb metacarpophalangeal extension, which reflects poor recovery of EPL function.

CONCLUSIONS

Overall, we observed better outcomes in those who underwent nerve transfer versus tendon transfer procedures. However, room still remains for improved thumb motion with both procedures.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Distal pronator teres motor branch transfer for wrist extension restoration in radial nerve paralysis

OBJECTIVE

The authors describe the anatomy of the motor branches of the pronator teres (PT) as it relates to transferring the nerve of the extensor carpi radialis brevis (ECRB) to restore wrist extension in patients with radial nerve paralysis. They describe their anatomical cadaveric findings and report the results of their nerve transfer technique in several patients followed for at least 24 months postoperatively.

METHODS

The authors dissected both upper limbs of 16 fresh cadavers. In 6 patients undergoing nerve surgery on the elbow, they dissected the branches of the median nerve and confirmed their identity by electrical stimulation. Of these 6 patients, 5 had had a radial nerve injury lasting 7-12 months, underwent transfer of the distal PT motor branch to the ECRB, and were followed for at least 24 months.

RESULTS

The PT was innervated by two branches: a proximal branch, arising at a distance between 0 and 40 mm distal to the medial epicondyle, responsible for PT superficial head innervation, and a distal motor branch, emerging from the anterior side of the median nerve at a distance between 25 and 60 mm distal to the medial epicondyle. The distal motor branch of the PT traveled approximately 30 mm along the anterior side of the median nerve; just before the median nerve passed between the PT heads, it bifurcated to innervate the deep head and distal part of the superficial head of the PT. In 30% of the cadaver limbs, the proximal and distal PT branches converged into a single trunk distal to the medial epicondyle, while they converged into a single branch proximal to it in 70% of the limbs. The proximal and distal motor branches of the PT and the nerve to the ECRB had an average of 646, 599, and 457 myelinated fibers, respectively.All patients recovered full range of wrist flexion-extension, grade M4 strength on the British Medical Research Council scale. Grasp strength recovery achieved almost 50% of the strength of the contralateral side. All patients could maintain their wrist in extension while performing grasp measurements.

CONCLUSIONS

The distal PT motor branch is suitable for reinnervation of the ECRB in radial nerve paralysis, for as long as 7-12 months postinjury.

Vascularized Thumb Metacarpal Periosteal Flap for Scaphoid Nonunion in Adolescents: A Prospective Cohort Study of 12 Patients

PURPOSE

To evaluate clinical and radiological outcomes after surgical treatment of scaphoid nonunion in adolescents with a vascularized thumb metacarpal periosteal pedicled flap (VTMPF).

METHODS

Twelve patients younger than 18 years with scaphoid nonunion, who underwent a VTMPF procedure without bone grafting, were included for this prospective cohort study, at a mean follow-up of 10.2 months. Patients were operated on by 3 different hand surgeons at 3 hand surgery institutions. All patients received a VTMPF, but with different scaphoid internal fixation modalities, in 10 cases using 1 or 2 retrograde 2-mm headless compression screws and in 2 cases without internal fixation.

RESULTS

In 11 boys and 1 girl, the mean age was 15.6 years. There were 1 type D1 nonunions (Herbert classification), 6 type D2, 2 type D3, and 2 type D4. Six patients had previously undergone an unsuccessful surgical attempt to treat their nonunion. The mean anterior bone defect was 3.5 mm in length. The patients experienced no postoperative complications. Successful consolidation was achieved in all cases, with 79% cross-sectional trabecular bridging at 12 weeks. Pain subsided after surgery and patients experienced improvements in both their Quick Disabilities of the Arm, Shoulder, and Hand (QuickDASH) and Modified Mayo Wrist Score (MMWS) results. Overall, 34% and 40% gains in strength and wrist motion, relative to the contralateral normal side, were observed.

CONCLUSIONS

In this study, the use of VTMPF for scaphoid nonunion in children and adolescents is associated with generally good outcomes.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Free Reverse Gracilis Muscle Combined With Steindler Flexorplasty for Elbow Flexion Reconstruction After Failed Primary Repair of Extended Upper-Type Paralysis of the Brachial Plexus

PURPOSE

To report the clinical outcomes of elbow flexion reconstruction using a reverse free gracilis muscle flap plus Steindler flexorplasty in patients with previously failed reconstruction of extended upper-type brachial plexus paralysis.

METHODS

Twenty-four male patients were reoperated upon an average of 45 months (SD, ± 45 months) after brachial plexus repair. The gracilis tendon was secured to the acromion, and the muscle belly was sutured to the biceps distal tendon. Vascular repair was performed preferentially end to end to the radial artery and cephalic vein. Nerve repair was achieved by coapting the nerve to the gracilis to motor fascicles of the median or ulnar nerve. The medial epicondyle was osteotomized, proximally advanced by 4 to 5 cm and secured to the anterior side of the humerus.

RESULTS

Active elbow flexion was restored in 23 of 24 patients. Sixteen patients ultimately achieved M4 strength, among whom 6 had full range of motion (ROM), and the remaining 10 recovered an average of 110° (95% confidence interval [95% CI], 100°-120°) of elbow flexion. Seven patients exhibited M3 elbow flexion strength recovery, which was associated with weaker hands and incomplete ROM, averaging 94° (95% CI, 86°-102°). There was, on average, a 10° (95% CI, 4.4°-15.6°). elbow flexion contracture. Among the 16 patients with M4 level recovery of elbow flexion, supination was partially restored in 12.

CONCLUSIONS

In patients previously operated upon, using a reversed free gracilis muscle flap in association with a Steindler procedure is effective as salvage surgery to restore elbow flexion and partial supination.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Transferring the Motor Branch of the Opponens Pollicis to the Terminal Division of the Deep Branch of the Ulnar Nerve for Pinch Reconstruction

PURPOSE

With ulnar nerve injuries, paralysis of the first dorsal interosseous (FDI) and the adductor pollicis (ADP) muscles weakens pinch. The likelihood that these muscles will be reinnervated following ulnar nerve repair around the elbow is very low. To overcome this obstacle, we propose a more distal repair: transferring the opponens pollicis motor branch (OPB) to the terminal division of the deep branch of the ulnar nerve (TDDBUN).

METHODS

We dissected 10 embalmed hands to study the anatomy of the thenar branches of the median nerve and TDDBUN. We also operated on 3 patients with recent ulnar nerve injuries around the elbow, suturing the ulnar nerve and transferring the OPB to the TDDBUN. Before and after surgery, we measured grasp, key pinch, and pinch-to-zoom strength using dynamometers. Pinch-to-zoom gesture consists of moving the index finger and thumb pulp toward each other for zooming out of an image on screen. Patients were followed for at least 15 months.

RESULTS

The thenar branch of the median nerve innervated the abductor pollicis brevis and opponens pollicis in all specimens, but only half the superficial head of the flexor pollicis brevis. The TDDBUN gave off a single motor branch to the transverse head of the ADP, 1 or 2 branches to the oblique head, and a final branch to the FDI. The ratio of myelinated fibers between the OPB and the TDDBUN was 3:5. Relative to the normal side, pinch-to-zoom strength was mostly affected by the ulnar nerve lesion, with strength decreased by 80% to 90%. After surgery, we observed reinnervation of the FDI and an 80% to 90% improvement in pinch-to-zoom strength.

CONCLUSIONS

Transferring the OPB to the TDDBUN provided reinnervation of the FDI and ADP, thereby contributing to pinch strength improvement.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic V.

Results of nerve grafting in radial nerve injuries occurring proximal to the humerus, including those within the posterior cord

OBJECTIVE Results of radial nerve grafting are largely unknown for lesions of the radial nerve that occur proximal to the humerus, including those within the posterior cord. METHODS The authors describe 13 patients with proximal radial nerve injuries who were surgically treated and then followed for at least 24 months. The patients' average age was 26 years and the average time between accident and surgery was 6 months. Sural nerve graft length averaged 12 cm. Recovery was scored according to the British Medical Research Council (BMRC) scale, which ranges from M0 to M5 (normal muscle strength). RESULTS After grafting, all 7 patients with an elbow extension palsy recovered elbow extension, scoring M4. Six of the 13 recovered M4 wrist extension, 6 had M3, and 1 had M2. Thumb and finger extension was scored M4 in 3 patients, M3 in 2, M2 in 2, and M0 in 6. CONCLUSIONS The authors consider levels of strength of M4 for elbow and wrist extension and M3 for thumb and finger extension to be good results. Based on these criteria, overall good results were obtained in only 5 of the 13 patients. In proximal radial nerve lesions, the authors now advocate combining nerve grafts with nerve or tendon transfers to reconstruct wrist, thumb, and finger extension.

Lunate Grafting Into the Radius for Lunate Fossa Reconstruction in Madelung Deformity

A 40-year-old woman presented with Madelung deformity and severe arthritic changes at both the radiocarpal and the distal radioulnar joints. She was treated by using her lunate as an osteochondral graft into the radius allowing reconstruction of the lunate fossa. The scaphoid and triquetrum were removed concomitantly and a Sauve-Kapandji procedure was performed. Complete bone healing was achieved. Ten years later, an excellent functional result was maintained, with a pain-free wrist, an acceptable wrist joint range of motion, as well as a favorable aesthetic appearance. This procedure may be indicated for patients with severe Madelung deformity with painful radiocarpal and distal radioulnar joints associated with severe arthritis changes.

Transfer of the Motor Branch of the Abductor Digiti Quinti for Thenar Muscle Reinnervation in High Median Nerve Injuries

PURPOSE

In high median nerve repairs, thenar muscle reinnervation is impossible because of the long distances over which axons must regenerate. To overcome this obstacle, we propose transferring the abductor digiti quinti motor branch (ADQMB) to the thenar branch of the median nerve (TBMN).

METHODS

We used 10 embalmed hands for anatomical and histological studies. Thereafter, 5 patients with a high median nerve injury underwent surgical reconstruction within 8 months of their accident and were followed for at least 10 months after surgery (mean, 13.2 months). We transferred the ADQMB to the TBMN. The median nerve was grafted in 4 patients and the motor branch of the extensor carpi radialis brevis was transferred to the anterior interosseous nerve in 3. Patients had pre- and postoperative evaluations of thumb range of motion and strength.

RESULTS

In cadaveric hands, the ADQMB was the first branch of the ulnar nerve to arise near the pisiform bone. The TBMN arose from the anterior surface of the median nerve, underneath the flexor retinaculum. Retrograde dissection of the TBMN allowed tension-free coaptation with the ADQMB. Both branches contained approximately 650 myelinated fibers. After surgery, all our patients improved thumb pronation, thenar eminence bulk, and abductor pollicis brevis British Medical Research Council score. They recovered approximately 75% of their normal-side grasp and pinch strength. No patient lost little finger abduction.

CONCLUSIONS

Transfer of the ADQMB to the TBMN reinnervated the thenar muscles, which improved thumb range of motion and strength.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic V.

Transfer of the musculocutaneous nerve branch to the brachialis muscle to the triceps for elbow extension: anatomical study and report of five cases

We report the study of the anatomical feasibility of transferring the nerve to the brachialis muscle to the upper medial head motor branch that innervate the triceps, and outcomes of such transfers in restoring elbow extension in five patients with posterior cord lesion of the brachial plexus. The length of the branches to the brachialis muscle measured 7.6 cm and the triceps upper medial head motor branch was 5 cm in 10 adult cadavers. Five male patients were treated with this transfer 5 months after the injury (range 4 to 6 months) after posterior cord injury of the brachial plexus with a mean follow-up of 31 months (range 28 to 36 months). Elbow extension scored M4 in all cases. No complications occurred. These preliminary results suggest that transferring the nerve to the brachialis muscle is an effective technique for the reconstruction of elbow extension after posterior cord brachial plexus injuries.

LEVEL OF EVIDENCE

IV.

Sensory deficits after a radial nerve injury

BACKGROUND

The aim of our study was to objectively test sensibility on the dorsal side of the hand in patients with radial nerve injury, to document deficits and to detect if surgery for sensory reconstruction is needed.

METHODS

Nineteen patients of mean age 31 ± 10 years were examined at a mean of 26.4 ± 27.8 months post radial nerve injury. Sensory mechanical thresholds on the dorsal surface of the hand were evaluated using Semmes-Weinstein monofilaments. Sensation was considered significantly impaired when there was no perception of a 2.0 gr. Semmes-Weinstein filament. Nociception was evaluated using Adson forceps.

RESULTS

Five patients had normal 2.0 monofilament perception. Two of these five also had normal perception of the lighter 0.05 monofilament. In nine patients, zones of impaired sensibility were restricted to the first web space. In combined radial and musculocutaneous nerve lesions, the zone of impaired sensibility extended to the dorsum of the third metacarpus and occasionally to the dorsal aspect of the thumb. This zone averaged being five times the size as in isolated radial nerve injuries. On average, the zone of decreased 0.05 monofilament perception was six times the size detected for the 2.0 monofilament. No patient had complete anesthesia over the dorsum of the hand. No patient complained about pain or numbness. Only one patient among four with a combined radial and musculocutaneous nerve injury required sensory reconstruction.

CONCLUSIONS

Minimal sensory abnormalities should be expected after a radial nerve injury. Patients likely neither warrant nor request sensory reconstruction.

Nerve and Free Gracilis Muscle Transfers for Thumb and Finger Extension Reconstruction in Long-standing Tetraplegia

PURPOSE

With spinal cord injuries, muscles below the level of the lesion remain innervated despite the absence of volitional control. This persistent innervation protects against denervation atrophy and may allow for nerve transfers to treat long-standing lesions within the spinal cord. We tested the hypothesis that in chronic spinal cord lesions, muscles remained viable for reinnervation.

METHODS

To test this hypothesis, we operated on 7 patients with tetraplegia to reconstruct thumb and finger extension after a mean interval of 5 years since injury. During surgery, if electrical stimulation of the posterior interosseous nerve (PIN) produced muscle contraction, the nerve to the supinator (NS) was transferred to the PIN. If no contractions were demonstrated, the muscles of the extensor compartment of the forearm were replaced via a free gracilis transfer with innervation supplied by the NS.

RESULTS

After an average of 26 months, M3 recovery of thumb and finger extension was observed in the 3 upper limbs from the 2 youngest patients who underwent a nerve transfer. None of the free gracilis-treated patients achieved scores above M2.

CONCLUSIONS

In our youngest patients aged 27 and 34 years, who were operated on 6 years after spinal cord injury, transfer of the NS to the PIN partially restored hand span.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic V.

The Towel Test: A Useful Technique for the Clinical and Electromyographic Evaluation of Obstetric Brachial Plexus Palsy

The towel test consists of covering an infant’s face with a towel and seeing if he/she can remove it with either arm. In this study it has been used to aid the clinical and electromyographic assessment of 21 infants with obstetric brachial plexus palsy. At 2 to 3 months, none of the 21 infants succeeded in removing the towel, either with their normal or affected arm. At 6 months, all the infants succeeded in removing the towel with their normal arm, but 11 could not with their affected arm, and the same was observed at a further assessment at 9 months. The towel test is a reliable technique for evaluating children with obstetric brachial plexus injuries.

Brachialis Muscle Transfer to the Forearm Muscles in Obstetric Brachial Plexus Palsy

Tendon transfers are frequently needed to improve hand function in obstetric brachial plexus injuries. The reconstruction cannot always be achieved using local donor transfers in the forearm as these are not always available. In such cases, we propose the use of the brachialis muscle as a useful donor for transfer. Five adolescents with obstetric brachial plexus palsy were operated on to reconstruct wrist extension and/or pronation using the brachialis muscle transfer to the pronator teres ( n = 1) extensor carpi radialis brevis ( n = 1) and extensor carpi radialis longus ( n = 3). Twelve months after surgery, average active motion recovery was 20° for wrist extension and 14° for pronation. Active and passive range of motion was similar.

Results of spinal accessory to suprascapular nerve transfer in 110 patients with complete palsy of the brachial plexus

OBJECTIVE

Transfer of the spinal accessory nerve to the suprascapular nerve is a common procedure, performed to reestablish shoulder motion in patients with total brachial plexus palsy. However, the results of this procedure remain largely unknown.

METHODS

Over an 11-year period (2002–2012), 257 patients with total brachial plexus palsy were operated upon in the authors' department by a single surgeon and had the spinal accessory nerve transferred to the suprascapular nerve. Among these, 110 had adequate follow-up and were included in this study. Their average age was 26 years (SD 8.4 years), and the mean interval between their injury and surgery was 5.2 months (SD 2.4 months). Prior to 2005, the suprascapular and spinal accessory nerves were dissected through a classic supraclavicular L-shape incision (n = 29). Afterward (n = 81), the spinal accessory and suprascapular nerves were dissected via an oblique incision, extending from the point at which the plexus crossed the clavicle to the anterior border of the trapezius muscle. In 17 of these patients, because of clavicle fractures or dislocation, scapular fractures or retroclavicular scarring, the incision was extended by detaching the trapezius from the clavicle to expose the suprascapular nerve at the suprascapular fossa. In all patients, the brachial plexus was explored and elbow flexion reconstructed by root grafting (n = 95), root grafting and phrenic nerve transfer (n = 6), phrenic nerve transfer (n = 1), or third, fourth, and fifth intercostal nerve transfer. Postoperatively, patients were followed for an average of 40 months (SD 13.7 months).

RESULTS

Failed recovery, meaning less than 30° abduction, was observed in 10 (9%) of the 110 patients. The failure rate was 25% between 2002 and 2004, but dropped to 5% after the staged/extended approach was introduced. The mean overall range of abduction recovery was 58.5° (SD 26°). Comparing before and after distal suprascapular nerve exploration (2005–2012), the range of abduction recovery was 45° (SD 25.1°) versus 62° (SD 25.3°), respectively (p = 0.002). In patients who recovered at least 30° of abduction, recovery of elbow flexion to at least an M3 level of strength increased the range of abduction by an average of 13° (p = 0.01). Before the extended approach, 2 (7%) of 29 patients recovered active external rotation of 20° and 120°. With the staged/extended approach, 32 (40%) of 81 recovered some degree of active external rotation. In these patients, the average range of motion measured from the thorax was 87° (SD 40.6°).

CONCLUSIONS

In total palsies of the brachial plexus, using the spinal accessory nerve for transfer to the suprascapular nerve is reliable and provides some recovery of abduction for a large majority of patients. In a few patients, a more extensive approach to access the suprascapular nerve, including, if necessary, dissection in the suprascapular fossa, may enhance outcomes.

Reappraisal of Clinical Deficits Following High Median Nerve Injuries

PURPOSE

To describe clinically apparent motor and sensory deficits in a cohort of 11 patients with isolated injury of the median nerve above the elbow and compare them against similar cases reported in the literature.

METHOD

Eleven patients of mean age 30 years (SD ± 14 years; 6 males, 5 females) were examined a mean of 21 weeks (SD ± 16 weeks) after an isolated high median nerve injury. Pronation, wrist flexion, and finger flexion range of motion and strength (British Medical Research Council scale) were evaluated. Grasp and lateral pinch strength were assessed bilaterally using a dynamometer. Thumb opposition was evaluated using the Kapandji score. Sensory impairment was considered significant when there was no perception of a 2.0-g Semmes-Weinstein filament.

RESULTS

Pronation was largely preserved in all patients to a mean range of motion of 52° (SD ± 13°), and pronation strength was M4 in 10 of 11 patients. Wrist flexion scored M5 in all patients. Thumb and index distal interphalangeal joint flexion were absent in all patients. In all patients, middle, ring, and little finger flexion was complete and scored M5. Thumb function scored above 5 in all patients, averaging 7.5 (SD ± 1.2) on the Kapandji scale. Grasp and pinch strength were 43% (SD ± 12%) and 36% (SD ± 11%) of the contralateral (normal) limb, respectively. Impaired sensation of a 2.0-g monofilament was found only in the palmar region over the middle and distal phalanges of the index and middle fingers and the distal phalanx of the thumb.

CONCLUSIONS

Noteworthy discrepancies were identified between the clinical motor and sensory deficits described in the literature and those observed in our patients.

CLINICAL RELEVANCE

In most patients with a high median nerve injury, only thumb and index flexion and palmar sensation warrant surgical reconstruction. Decreased grasp and pinch strength was a major finding that should also be addressed by surgery.

TYPE OF STUDY/LEVEL OF EVIDENCE

Prognostic IV.

Results of nerve grafting in radial nerve injuries occurring proximal to the humerus, including those within the posterior cord

OBJECT

Results of radial nerve grafting are largely unknown for lesions of the radial nerve that occur proximal to the humerus, including those within the posterior cord.

METHODS

The authors describe 13 patients with proximal radial nerve injuries who were surgically treated and then followed for at least 24 months. The patients’ average age was 26 years and the average time between accident and surgery was 6 months. Sural nerve graft length averaged 12 cm. Recovery was scored according to the British Medical Research Council (BMRC) scale, which ranges from M0 to M5 (normal muscle strength).

RESULTS

After grafting, all 7 patients with an elbow extension palsy recovered elbow extension, scoring M4. Six of the 13 recovered M4 wrist extension, 6 had M3, and 1 had M2. Thumb and finger extension was scored M4 in 3 patients, M3 in 2, M2 in 2, and M0 in 6.

CONCLUSIONS

The authors consider levels of strength of M4 for elbow and wrist extension and M3 for thumb and finger extension to be good results. Based on these criteria, overall good results were obtained in only 5 of the 13 patients. In proximal radial nerve lesions, the authors now advocate combining nerve grafts with nerve or tendon transfers to reconstruct wrist, thumb, and finger extension.

Results of wrist extension reconstruction in C5-8 brachial plexus palsy by transferring the pronator quadratus motor branch to the extensor carpi radialis brevis muscle

OBJECT The objective of this study was to report the results of pronator quadratus (PQ) motor branch transfers to the extensor carpi radialis brevis (ECRB) motor branch to reconstruct wrist extension in C5-8 root lesions of the brachial plexus. METHODS Twenty-eight patients, averaging 24 years of age, with C5-8 root injuries underwent operations an average of 7 months after their accident. In 19 patients, wrist extension was impossible at baseline, whereas in 9 patients wrist extension was managed by activating thumb and wrist extensors. When these 9 patients grasped an object, their wrist dropped and grasp strength was lost. Wrist extension was reconstructed by transferring the PQ motor to the ECRB motor branch. After surgery, patients were followed for at least 12 months, with final follow-up an average of 22 months after surgery. RESULTS Successful reinnervation of the ECRB was demonstrated in 27 of the 28 patients. In 25 of the patients, wrist extension scored M4, and in 2 it scored M3. CONCLUSIONS In C5-8 root injuries, wrist extension can be predictably reconstructed by transferring the PQ motor branch to reinnervate the ECRB.

Nerve transfers for elbow and finger extension reconstruction in midcervical spinal cord injuries

OBJECT

The objective of this study was to report the results of elbow, thumb, and finger extension reconstruction via nerve transfer in midcervical spinal cord injuries.

METHODS

Thirteen upper limbs from 7 patients with tetraplegia, with an average age of 26 years, were operated on an average of 7 months after a spinal cord injury. The posterior division of the axillary nerve was used to reinnervate the triceps long and upper medial head motor branches in 9 upper limbs. Both the posterior division and the branch to the middle deltoid were used in 2 upper limbs, and the anterior division of the axillary nerve in the final 2 limbs. For thumb and finger extension reconstruction, the nerve to the supinator was transferred to the posterior interosseous nerve.

RESULTS

In 22 of the 27 recipient nerves, a peripheral type of palsy with muscle denervation was identified. At an average of 19 months follow-up, elbow strength scored M4 in 11 upper limbs and M3 in 2, according to the British Medical Research Council scale. Thumb extension scored M4 in 8 upper limbs and scored M3 in 4. Finger extension scored M4 in 12 hands. No donor-site deficits were reported or observed.

CONCLUSIONS

Nerve transfers are effective at restoring elbow, thumb, and finger extension in patients with a midcervical spinal cord injury, which occurs in the majority of patients with a peripheral type of palsy with muscle denervation in their upper limbs. Efforts should be made to perform operations in these patients within 12 months of injury.

Transfer of the radial nerve branch to the extensor carpi radialis brevis to the anterior interosseous nerve to reconstruct thumb and finger flexion

PURPOSE

To report our experiences reconstructing thumb and finger flexion in patients with extensive palsy of the upper limb by transferring the radial nerve branch to the extensor carpi radialis brevis (ECRB) to the anterior interosseous nerve (AIN).

METHODS

Within 8 months after injury, 4 patients with either a combined high median/ulnar nerve palsy or C7-T1 brachial plexus root avulsion underwent surgical reconstruction for thumb and finger flexion. As part of the reconstructive procedure, the branch of the radial nerve to the ECRB was transferred to the AIN.

RESULTS

At final evaluation, which averaged 13 months postoperatively, all patients had recovered full finger and thumb flexion, scoring M4 per Medical Research Council guidelines. Average grasp strength was 5 kg, and pinch strength was 2 kg. Even in anesthetic fingers and with their eyes closed, patients could correctly identify passive extension of their distal interphalangeal joints. Wrist extension was preserved in all patients.

CONCLUSIONS

In 4 patients, transfer of the branch of the radial nerve to the ECRB to the AIN predictably reconstructed thumb and finger flexion. Finger flexion also recovered in those fingers in which the flexor digitorum profundus was primarily innervated by the ulnar nerve. Despite extended sensory deficits, patients ultimately were able to use their hands regularly in daily life.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic III.

The median nerve consistently drives flexion of the distal phalanx of the ring and little fingers: Interest in finger flexion reconstruction by nerve transfers

Surgeons believe that in high ulnar nerve lesion distal interphalangeal joint (DIP) flexion of the ring and little finger is abolished. In this article, we present the results of a study on innervation of the flexor digitorum profundus of the ring and little fingers in five patients with high ulnar nerve injury and in 19 patients with a brachial plexus, posterior cord, or radial nerve injury. Patients with ulnar nerve lesion were assessed clinically and during surgery for ulnar nerve repair we confirmed complete lesion of the ulnar nerve in all cases. In the remaining 19 patients, during surgery, either the median nerve (MN) or the anterior interosseous nerve (AIN) was stimulated electrically and DIP flexion of the ring and little fingers evaluated. All patients with high ulnar nerve lesions had active DIP flexion of the ring and little fingers. Strength scored M4 in the ring and M3-M4 in the little finger. Electrical stimulation of either the MN or AIN produced DIP flexion of the ring and little fingers. Contrary to common knowledge, we identified preserved flexion of the distal phalanx of the ring and little fingers in high ulnar nerve lesions. On the basis of these observations, nerve transfers to the AIN may provide flexion of all fingers.

The C5 root dermatome enlarges and modulates hand pain in total brachial plexus palsy

Hand pain is a major complaint in 80% of the patients with complete brachial plexus palsy; and, in 80% of these patients, the C5 root is ruptured and the C6-T1 roots avulsed from the spinal cord. It has been suggested that pain in brachial plexus injuries may not arise from avulsed roots, but rather from ruptured roots. Traditionally the C5 root dermatome does not extend to the hand. We have hypothesized that in total lesions of the brachial plexus the C5 root dermatome expands, reaching the hand. In 20 patients with confirmed C5 root rupture and C6-T1 root avulsion, we investigated the distribution of C5 root paresthesia six to eight weeks after grafting. After cervical percussion in search of Tinel’s sign, maps related to reported paresthesia were drawn on the affected limb. We observed that paresthesia following C5 root percussion reached the hands and fingers, dermatomes linked to the C6 and C8 roots. Immediately after percussion, for a few seconds, 14 patients who complained of pain during examination reported the augmentation of numbness and pain resolution. After brachial plexus injury, the C5 root dermatome expands and modulates hand pain.

Nerve transfer from triceps medial head and anconeus to deltoid for axillary nerve palsy

PURPOSE

To report our results with reconstruction of the axillary nerve by transferring the branch to the triceps lower medial head and anconeus to the anterior division of the axillary nerve.

METHODS

This study included 9 patients with isolated injury of the axillary nerve. Their average age ± SD was 35 ± 9 years, and the mean interval ± SD between injury and surgery was 6.6 ± 2.6 months. Through a posterior arm approach, the radial nerve branch to the lower triceps medial head and anconeus was transferred to the anterior division of the axillary nerve. We observed patients for a mean of 34 ± 7 months. At final evaluation, we measured range of shoulder motion, shoulder abduction and elbow extension strength, and abduction endurance. Patients were assessed via the deltoid extension lag test and abduction-in-internal-rotation test.

RESULTS

All patients recovered deltoid function and maintained full active elbow extension. Seven of 9 patients recovered from lagging abduction in internal rotation. Abduction strength improved from approximately 40% that of the normal side at 90° of abduction preoperatively to 60% of normal strength postoperatively. There was improved endurance in abduction from approximately 25% to 65% that of the normal side, which was sufficient to eliminate all reports of shoulder pain or fatigability.

CONCLUSIONS

Transfer of the radial nerve branch for the lower triceps medial head and anconeus to the anterior division of the axillary nerve proved to be an effective method of deltoid reinnervation.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Variation in nerve autograft length increases fibre misdirection and decreases pruning effectiveness. An experimental study in the rat median nerve

OBJECTIVES

In the clinical set, autologus nerve grafts are the current option for reconstruction of nerve tissue losses. The length of the nerve graft has been suggested to affect outcomes. Experiments were performed in the rat in order to test this assumption and to detect a possible mechanism to explain differences in recovery.

METHODS

The rat median nerve was repaired by ulnar nerve grafts of different lengths. Rats were evaluated for 12 months by behavioural assessment and histological studies, including ATPase myofibrillary histochemistry and retrograde neuronal labelling.

RESULTS

It was demonstrated that graft length interferes in behavioural functional recovery that here correlates to muscle weight recovery. Short nerve grafts recovered faster and better. Reinnervation was not specific either at the trunk level or in the muscle itself. The normal mosaic pattern of Type I muscle fibres was never restored and their number remained largely augmented. An increment in the number of motor fibres was observed after the nerve grafting in a predominantly sensory branch in all groups. This increment was more pronounced in the long graft group. In the postoperative period, about a 20% reduction in the number of misdirected motor fibres occurred in the short nerve graft group only.

CONCLUSION

Variation in the length of nerve grafts interferes in behavioural recovery and increases motor fibres misdirection. Early recovery onset was related to a better outcome, which occurs in the short graft group.

Clinical findings in C5-C6 and C5-C7 root palsies with brachial plexus traction lesions

Stretch injuries of the C5-C7 roots of the brachial plexus traditionally have been associated with palsies of shoulder abduction/external rotation, elbow flexion/extension, and wrist, thumb, and finger extension. Based on current myotome maps we hypothesized that, as far as motion is concerned, palsies involving C5-C6 and C5-C7 root injuries should be similar. In 38 patients with upper-type palsies of the brachial plexus, we examined for correlations between clinical findings and root injury level, as documented by CT tomomyeloscan. Contrary to commonly held beliefs, C5-C7 root injuries were not associated with loss of extension of the elbow, wrist, thumb, or fingers, but residual hand strength was much lower with C5-C7 vs C5-C6 lesions.

The Anabolic Steroid Nandrolone Enhances Motor and Sensory Functional Recovery in Rat Median Nerve Repair With Long Interpositional Nerve Grafts

Background. Recovery from peripheral nerve repair is frequently incomplete. Hence drugs that enhance nerve regeneration are needed clinically. Objectives. To study the effects of nandrolone decanoate in a model of deficient reinnervation in the rat. Methods. In 40 rats, a 40-mm segment of the left median nerve was removed and interposed between the stumps of a sectioned right median nerve. Starting 7 days after nerve grafting and continuing over a 6-month period, we administered nandrolone at a dose of 5 mg/kg/wk to half the rats (n = 20). All rats were assessed behaviorally for grasp function and nociceptive recovery for up to 6 months. At final assessment, reinnervated muscles were tested electrophysiologically and weighed. Results were compared between rats that had received versus not received nandrolone and versus 20 nongrafted controls. Results. Rats in the nandrolone group recovered finger flexion faster. At 90 days postsurgery, they had recovered 42% of normal grasp strength versus just 11% in rats grafted but not treated with nandrolone. At 180 days, the average values for grasp strength recovery in the nandrolone and no-nandrolone groups were 40% and 33% of normal values for controls, respectively. At 180 days, finger flexor muscle twitch strength was 16% higher in treated versus nontreated rats. Thresholds for nociception were not detected in either group 90 days after nerve grafting. At 180 days, nociceptive thresholds were significantly lower in the nandrolone group. Conclusions. Nandrolone decanoate improved functional recovery in a model of deficient reinnervation.

Muscle fiber type reorganization and behavioral functional recovery of rat median nerve repair with vascularized or conventional nerve grafts

In 1921, Ney introduced the concept of nerve grafts with preservation of the vascular blood supply. Today, over 70 years later, the use of vascularized nerve grafts in clinical practice is still controversial. Although the results of experiments with vascularized and conventional nerve grafts have been compared on the basis of electrophysiological and histological observations, the literature includes no vaJid comparison of the clinical and behavioral significance of these results. Therefore, in the experiments reported here, the rat median nerve was repaired using either a vascularized or a conventional ulnar nerve graft. The rates behavior between 0 and 360 days after surgery was assessed by the grasping test. Nienty-five, 120, 150, 210 and 360 days after surgery rats were submitted to retrograde labeling studies and muscle samples were removed and studied using routine hematoxilin-eosin and ATPase histochemistry. The present study provides evidence that autografting is a reliable procedure for nerve repair. Motor axons were able to reinnervate and largely respecify muscle properties. Reinnervation was not selective either at the nerve trunk level or at the muscle fiber. A mechanism of collateral pruning might have been present in the early phases of reinnervation. This mechanism was, however, self limiting and unable to correct all wrong projections. A mechanism of terminal sprouting was in part responsible for time-related improvement in muscle force recovery. While the present study does provide evidence that recovery was 20% faster in rats with vascularized grafts than in those with conventional grafts (P < 0.0001), it does not, however, provide evidence for better functional recovery in long-term assessment.

Transfer of nerve branch to the brachialis to reconstruct elbow extension in incomplete tetraplegia: case report

We undertook a brachialis to triceps nerve transfer to restore elbow extension in a 53-year-old man 5 months after he sustained a spine injury that resulted in a central cord syndrome. Within 3 months of surgery, the patient had recovered active elbow extension and had M3 level strength, which increased to M4 and 5 kg of strength by 12 months postoperatively. Despite transferring an antagonist nerve for triceps reinnervation, the patient had no problems controlling active elbow flexion-extension. Harvesting the brachialis nerve caused no permanent decrease in elbow flexion strength.

Grafting the C5 Root to the Musculocutaneous Nerve Partially Restores Hand Sensation in Complete Palsies of the Brachial Plexus

BACKGROUND:

In complete brachial plexus palsy, we have hypothesized that grafting to the musculocutaneous nerve should restore some hand sensation because the musculocutaneous nerve can drive hand sensation directly or via communication with the radial and median nerves.

OBJECTIVE:

To investigate sensory recovery in the hand and forearm after C5 root grafting to the musculocutaneous nerve in patients with a total brachial plexus injury.

METHODS:

Eleven patients who had recovered elbow flexion after musculocutaneous nerve grafting from a preserved C5 root and who had been followed for a minimum of 3 years were screened for sensory recovery in the hand and forearm. Six matched patients who had not undergone surgery served as controls. Methods of assessment included testing for pain sensation using Adson forceps, cutaneous pressure threshold measurements using Semmes-Weinstein monofilaments, and the static 2-point discrimination test. Deep sensation was evaluated by squeezing the first web space, and thermal sensation was assessed using warm and cold water.

RESULTS:

All grafted patients recovered sensation in a variable territory extending from just over the thenar eminence to the entire lateral forearm and hand. Seven patients were capable of perceiving 2-0 monofilament pressure on the thenar eminence, palm, and dorsoradial aspect of the hand. All could differentiate warm and cold water. None recovered 2-point discrimination. None of the patients in the control group recovered any kind of sensation in the affected limb.

CONCLUSION:

Grafting the musculocutaneous nerve can restore nociceptive sensation on the radial side of the hand.

C5–8 brachial plexus root injury: the “T-1 hand”

Object

Classically, C5–7 root injuries of the brachial plexus have been associated with palsies of shoulder abduction/external rotation, elbow flexion/extension, and wrist, thumb, and finger extension. However, current myotome maps generally indicate that C-8 participates in the innervation of thumb and finger extensors. Therefore, the authors have hypothesized that, for palsies of the thumb and finger extensors, the injury should affect the C-5 through C-8 roots.

Methods

The authors tested their hypothesis in 30 patients with upper-type palsies of the brachial plexus. They traced a correlation between clinical findings and root injury, as documented by CT myelography, direct visualization during surgery, and electrophysiological studies.

Results

In C5–8 root injuries, shoulder abduction and external rotation were paralyzed, and in all patients, wrist extensors were paralyzed. However, in 22 of the 30 patients, wrist extension was possible, because of contraction of the extensor digitorum communis and extensor pollicis longus. Wrist flexion and pronation also were preserved. The T-1 root contributed significantly to innervation of the thumb and finger flexors, ensuring 34% grasping and 40% pinch strength relative to the normal side. Hand sensation was largely preserved.

Conclusions

Based on the authors' observations, they suspect that the clinical scenario previously attributed to a C5–7 root injury is, in fact, a C5–8 root injury. The authors propose referring to this partial palsy of the brachial plexus as a “T-1 hand.”

Transfer of the Distal Terminal Motor Branch of the Extensor Carpi Radialis Brevis to the Nerve of the Flexor Pollicis Longus

BACKGROUND:

In tetraplegics, thumb and finger motion traditionally has been reconstructed via orthopedic procedures. Although rarely used, nerve transfers are a viable method for reconstruction in tetraplegia.

OBJECTIVE:

To investigate the anatomic feasibility of transferring the distal branch of the extensor carpi radialis brevis (ECRB) to the flexor pollicis longus (FPL) nerve and to report our first clinical case.

METHODS:

We studied the motor branch of the ECRB and FPL in 14 cadaveric upper limbs. Subsequently, a 24-year-old tetraplegic man with preserved motion in his shoulder, elbow, wrist, and finger extension, but paralysis of thumb and finger flexion underwent surgery. Seven months after trauma, we transferred the brachialis muscle with a tendon graft to the flexor digitorum profundus. The distal nerve of the ECRB was transferred to the FPL nerve.

RESULTS:

The branch to the ECRB entered the muscle in its anterior and proximal third. After sending out a first collateral, the nerve runs for 2.4 cm alongside the muscle and bifurcates intramuscularly. A main branch from the anterior interosseous nerve, which entered the muscle 3 cm from its origin on the radius, innervated the FPL. The ECRB and FPL nerves had similar diameters (∼1 mm) and numbers of myelinated fibers (∼180). In our patient, 14 months after surgery, pinching and grasping were restored and measured 2 and 8 kg strength, respectively.

CONCLUSION:

Transfer of the ECRB distal branch to the FPL is a viable option to reconstruct thumb flexion.

Transfer of the teres minor motor branch for triceps reinnervation in tetraplegia

In a case involving tetraplegia and paralysis of elbow extension, the authors transferred teres minor branches to the nerve of the triceps long head. Surgery was performed bilaterally 9 months after the patient sustained a spinal cord injury. Fourteen months postoperatively, elbow extension was complete (British Medical Research Council Score M4). Harvesting of the teres minor motor branch produced no deficits in shoulder function. In patients with tetraplegia, nerve transfer seems to be a promising new alternative for elbow extension reconstruction.

Very distal sensory nerve transfers in high median nerve lesions

PURPOSE

We report on the results of reconstruction of fingertip sensation by very distal nerve transfer in 8 patients with high median nerve lesions.

METHODS

Before surgery, patients underwent sensory testing of the hand using Semmes-Weinstein monofilaments. All patients had surgery within 1 year of trauma. For sensory reconstruction, branches of the radial nerve on the proximal phalanx of the index and thumb were sutured to the ulnar proper digital nerve of the thumb and radial proper digital nerve of the index finger. Patients were followed up for 12 months.

RESULTS

After median nerve lesions, zones of lost protective sensation were confined to the middle and index finger and the thumb. Sensation on the palm of the hand and proximal phalanx was preserved. Radial nerve transfer to palmar nerves restored protective or better sensation to the fingertips in all patients. Better results were observed for the thumb. Locognosia was acquired in all thumbs, and in 4 of 8 index fingers. Good results were detected even in patients who had undergone surgery later than 6 months after injury.

CONCLUSIONS

Fingertip sensation can be restored by very distal nerve transfer of radial nerve branches to palmar nerves at the level of the proximal phalanx. This method of reconstruction appears useful in high median nerve lesions. In chronic lesions of the median nerve at the wrist and lesions in older patients, very distal nerve transfers might be adjunct to nerve grafting.

Transfer of the Platysma Motor Branch to the Accessory Nerve in a Patient With Trapezius Muscle Palsy and Total Avulsion of the Brachial Plexus

BACKGROUND AND IMPORTANCE:

To report on the successful use of a platysma motor nerve transfer to the accessory nerve in a patient with concomitant trapezius and brachial plexus palsy.

CLINICAL PRESENTATION:

A 20-year-old man presented with total avulsion of the right brachial plexus combined with palsies of the accessory and phrenic nerve. The patient was operated on 4 months after his injury. The accessory nerve was repaired via direct transfer of the platysma motor branch. The contralateral C7 root was connected to the musculocutaneous nerve, and the hemihypoglossal nerve was grafted to the suprascapular nerve. Two intercostal nerves were attached to the triceps long head motor branch.

CONCLUSION:

Within 20 months of surgery, the patient regained full reinnervation of the upper trapezius muscle. Elbow flexion scored M3+, and 30° active shoulder abduction was observed. Triceps reinnervation was poor. Platysma motor branch transfer to the accessory nerve is a viable alternative to reinnervate the trapezius muscle.