The natural history of recovery of elbow flexion after obstetric brachial plexus injury managed without nerve repair.

In this study, we report the outcome for spontaneous recovery of elbow flexion in obstetric brachial plexus injury managed without nerve reconstruction. Excluding those with transient paralysis, our records revealed 152 children with obstetric brachial plexus injury born before our unit routinely offered brachial plexus reconstruction. Five had had nerve repairs. Of the remainder, only one patient had insufficient flexion to reach their mouth. Elbow flexion started to recover clinically at a mean age of 4 months for Narakas Group 1, 6 months for Group 2, 8 months for Group 3 and 12 months for Group 4. The mean active range of elbow flexion, in 44 cases, was 138°. The mean isometric elbow flexion strength, in 39 patients, was 63% (range 23%-100%) of the normal side. It appears to be rare for elbow flexion not to recover spontaneously, although recovery occurs later in more severe injuries. It is doubtful if nerve reconstruction can improve elbow flexion above the likely spontaneous recovery in babies with obstetric brachial plexus injuries. LEVEL OF EVIDENCE: II.

Refinement of myotome values in the upper limb: Evidence from brachial plexus injuries.

PURPOSE: We reviewed patients with partial supraclavicular brachial plexus injuries in order to refine the myotome values of the upper limb. METHODS: Forty-two patients with defined partial injuries to the supraclavicular brachial plexus were reviewed from a prospective database. The injuries patterns covered C5, C5-6, C5-7, C5-8, C7-T1 and C8-T1 roots. Upper plexus injuries were classified on the basis of surgical exploration and intraoperative stimulation and lower plexus injuries from MRI. RESULTS: Flexor Carpi Radialis (FCR) was paralyzed in C5-7 injuries, in addition to paralysis of deltoid, supraspinatus, infraspinatus and biceps, when compared to C5-6 injuries. Complete paralysis of Flexor Digitorum Profundus (FDP) and Flexor Digitorum Superficialis (FDS) to all digits was identified in C7-T1 injuries. In C5-8 injuries weakness was noted in FDP of ulnar digits and intrinsics innervated by the ulnar nerve, while in C8-T1 injuries paralysis was noted in the FDP to the radial digits. All patients with C8-T1 injuries had paralysis of FDS and the thenar muscles. CONCLUSIONS: In upper plexus injuries paralysis of FCR indicated involvement of C7 root in addition to C5 and C6 roots. The results provide new detail of innervation of muscles acting on the hand. Flexor muscles and intrinsic muscles of the thumb and radial fingers (median nerve) have an important contribution from T1, while for those acting on the ulnar digits (ulnar nerve) the main contribution is from C8 with some input from C7. T1 also gives consistent innervation to extensor pollicis longus. A revised myotome chart for the upper limb is proposed.

Timing of surgical reconstruction for closed traumatic injury to the supraclavicular brachial plexus.

While it is widely accepted that cases of traumatic injury to the brachial plexus benefit from early surgical exploration and repair, with results deteriorating with long delays, policies vary regarding the exact timing of intervention. This is one of a pair of review articles considering the clinical issues, investigations, and surgical factors relating to management of injuries to the supraclavicular brachial plexus, as well as evidence from experimental work and clinical outcomes.In this article Mr Hems outlines when waiting may be advantageous, allowing for further investigation to help clarify the extent of the injury and thus the best surgical options.

End-to-side nerve repair in a large animal model: how does it compare with conventional methods of nerve repair?

A large animal (sheep) model was used to compare nerve axon regeneration and return of muscle function after a median-to-ulnar nerve end-to-side neurorrhaphy technique with conventional, clinically established, methods of nerve repair and untreated controls. Three groups of sheep were allocated to end-to-side repair (12 animals), a conventional method of nerve repair (18 animals), or a control group (eight animals). After a year nerve repairs were assessed electrophysiologically and histologically, and the muscles supplied by the repaired nerves were assessed physiologically. There were no significant differences in the outcomes of nerve repair between different conventional techniques. Half of the end-to-side nerve repairs supported nerve regeneration. The functional outcomes of the end-to-side repairs were inferior to conventional techniques which were, in turn, inferior to controls. End-to-side neurorrhaphy supported nerve regeneration, but the reliability of this technique is called into question and its use as a clinical tool can only be recommended as a salvage procedure.

Injuries of the terminal branches of the infraclavicular brachial plexus: patterns of injury, management and outcome.

We reviewed 101 patients with injuries of the terminal branches of the infraclavicular brachial plexus sustained between 1997 and 2009. Four patterns of injury were identified: 1) anterior glenohumeral dislocation (n = 55), in which the axillary and ulnar nerves were most commonly injured, but the axillary nerve was ruptured in only two patients (3.6%); 2) axillary nerve injury, with or without injury to other nerves, in the absence of dislocation of the shoulder (n = 20): these had a similar pattern of nerve involvement to those with a known dislocation, but the axillary nerve was ruptured in 14 patients (70%); 3) displaced proximal humeral fracture (n = 15), in which nerve injury resulted from medial displacement of the humeral shaft: the fracture was surgically reduced in 13 patients; and 4) hyperextension of the arm (n = 11): these were characterised by disruption of the musculocutaneous nerve. There was variable involvement of the median and radial nerves with the ulnar nerve being least affected. Surgical intervention is not needed in most cases of infraclavicular injury associated with dislocation of the shoulder. Early exploration of the nerves should be considered in patients with an axillary nerve palsy without dislocation of the shoulder and for musculocutaneous nerve palsy with median and/or radial nerve palsy. Urgent operation is needed in cases of nerve injury resulting from fracture of the humeral neck to relieve pressure on nerves.

Management strategies for shoulder reconstruction in obstetric brachial plexus injury with special reference to loss of internal rotation after surgery.

We assessed the outcomes in 24 of 25 children (mean age 3 years) who had soft-tissue shoulder reconstruction procedures for obstetric brachial plexus injuries. All had latissimus dorsi and teres major transfers to strengthen external rotation combined with subscapularis lengthening, reduction of posterior dislocation or subluxation, and humeral osteotomy, if necessary. At a mean follow-up of 3.8 years, the mean Mallet score improved from 12.3 preoperatively to 17.4 postoperatively, active external rotation improved from 21° to 32°, and passive external rotation improved from 26° to 67°. The shoulder remained in joint in all patients. Active internal rotation deteriorated in nine shoulders, two requiring secondary internal rotation osteotomy. Combined soft tissue rebalancing and bony procedures gives reliable shoulder function improvement. Care is required regarding the effect on internal rotation.

Load transfer through the radiocarpal joint and the effects of partial wrist arthrodesis on carpal bone behaviour: a finite element study.

A finite element model of the wrist was developed to simulate mechanical changes that occur after surgery of the wrist. After partial arthrodesis, the wrist will experience altered force transmission during loading. Three different types of partial arthrodesis were investigated - radiolunate, radioscaphoid, and radioscapholunate - and compared with the healthy untreated wrist. The results showed that the compressive forces on the radiocarpal joint decreased compared with the untreated wrist with both radiolunate and radioscaphoid fusions. The load transmission through the midcarpal joints varied depending on arthrodesis type. The forces in the extrinsic ligaments decreased with the fusion, most noticeably in the dorsal radiotriquetral ligament, but increased in the dorsal scaphotriquetral ligament. From the results of the study it can be concluded that the radioscapholunate fusion shows the most biomechanically similar behaviour out of the three fusion types compared with the healthy wrist. The modelling described in this paper may be a useful approach to pre-operative planning in wrist surgery.

Open reduction and plate fixation of dorsally displaced fractures of the distal radius: surgical technique, clinical and radiological outcome.

Thirty-five unstable dorsally displaced fractures of the distal radius in 34 patients (mean age 39) were studied; 28 fractures were intra-articular. All fractures had open reduction and fixation, through a dorsal approach, with mini-fragment plates placed between the first and second dorsal tendon compartments and deep to the fourth compartment. A congruous reduction of the articular surface was obtained in all cases. Twenty-four patients were available for follow-up (median 38 months). The Modified Mayo wrist score was excellent in 12 cases, good in four, and fair in eight. The median Patient Evaluation Measure score was 23.5. There were no cases of extensor tendon rupture. Radiographic assessment at follow-up showed a mean palmar angle of 6 degrees. There was evidence of osteoarthritis in six patients who had had intra-articular fractures. Open reduction and plating gives satisfactory medium term results for treatment of displaced intra-articular fractures of the distal radius in young patients.

A three-dimensional finite element model of maximal grip loading in the human wrist.

The aim of this work was to create an anatomically accurate three-dimensional finite element model of the wrist, applying subject-specific loading and quantifying the internal load transfer through the joint during maximal grip. For three subjects, representing the anatomical variation at the wrist, loading on each digit was measured during a maximal grip strength test with simultaneous motion capture. The internal metacarpophalangeal joint load was calculated using a biomechanical model. High-resolution magnetic resonance scans were acquired to quantify bone geometry. Finite element analysis was performed, with ligaments and tendons added, to calculate the internal load distribution. It was found that for the maximal grip the thumb carried the highest load, an average of 72.2 +/- 20.1 N in the neutral position. Results from the finite element model suggested that the highest regions of stress were located at the radial aspect of the carpus. Most of the load was transmitted through the radius, 87.5 per cent, as opposed to 12.5 per cent through the ulna with the wrist in a neutral position. A fully three-dimensional finite element analysis of the wrist using subject-specific anatomy and loading conditions was performed. The study emphasizes the importance of modelling a large ensemble of subjects in order to capture the spectrum of the load transfer through the wrist due to anatomical variation.

Assessment of a diagnostic questionnaire and protocol for management of carpal tunnel syndrome.

One hundred and fifty-two patients with suspected carpal tunnel syndrome (CTS) completed a questionnaire, including questions about the location of paraesthesia, nocturnal pain, the effect of shaking the hand, relief by use of a wrist splint and impairment of manual dexterity. A score was derived from the symptom questionnaire and clinical signs including Tinel's test, Phalen's test, and altered sensation. Nerve conduction studies (NCS) were done in 91 cases in which the diagnosis of CTS was in doubt. A threshold questionnaire score was selected as indicating a diagnosis of CTS. Sixty-six patients were predicted to have CTS. When compared with the results of NCS this score had a specificity of 67% and sensitivity of 82%. Ninety-five patients underwent carpal tunnel release. A management model has been developed based on the questionnaire score for symptoms and signs.

Extrapleural apical fluid collection: an important sign on plain X-ray suggesting a pre-ganglionic brachial plexus injury.

Forty of 136 consecutive patients referred for management of brachial plexus injuries had closed supraclavicular injuries. The results of the initial chest X-rays were available for 29 patients. Nine had avulsion of the C8 and T1 nerve roots from the spinal cord. Eight cases had MR confirmation of lower root avulsion, six of these cases were confirmed surgically and none had any long-term clinical recovery. Twenty had partial brachial plexus injuries without avulsion of these roots. Seven of nine patients with avulsion of C8 and T1 had an extrapleural apical fluid collection. One of these had a fractured first rib. Two of 20 without avulsion had an extrapleural apical fluid collection. Both had fractured the first rib. The difference in incidence of extrapleural apical fluid collection between the two groups, excluding those cases with first rib fractures, was statistically significant. Without a first rib fracture, an ipsilateral extrapleural apical haematoma on a plain chest X-ray of patients with brachial plexus injury strongly suggests pre-ganglionic injury to the lower roots.

Peroneal nerve damage associated with the proximal locking screws of the AIM tibial nail.

We report a case of division of the deep peroneal nerve resulting from a drill used in the insertion of an oblique proximal locking screw in an AIM tibial intramedullary nail (DePuy). Operative findings and anatomical study indicate there is a risk of damage to the peroneal nerve associated with the oblique proximal locking screws used in this nail design. If a patient has peroneal nerve palsy after nailing of the tibia, the possibility of nerve division should be considered, so that early exploration and repair of the nerve can be performed.