Peripheral nerve injuries (PNI) occur in 10% of combat casualties. In the immediate field-hospital setting, an insensate limb can affect the surgeon's assessment of limb viability and in the long-term PNI remain a source of considerable morbidity. Therefore the aims of this study are to document the recovery of combat PNI, as well as report on the effect of current medical management in improving functional outcome. In this study, we present the largest series of combat related PNI in Coalition troops since World War II.

From May 2007 – May 2010, 100 consecutive patients (261 nerve injuries) were prospectively reviewed in a specialist PNI clinic. The functional recovery of each PNI was determined using the MRC grading classification (good, fair and poor). In addition, the incidence of neuropathic pain, the results of nerve grafting procedures, the return of plantar sensation, and the patients' current military occupational grading was recorded.

At mean follow up 26.7 months, 175(65%) of nerve injuries had a good recovery, 57(21%) had a fair recovery and 39(14%) had a poor functional recovery. Neuropathic pain was noted in 33 patients, with Causalgia present in 5 cases. In 27(83%) patients, pain was resolved by medication, neurolysis or nerve grafting. In 35 cases, nerve repair was attempted at median 6 days from injury. Of these 62%(22) gained a good or fair recovery with 37%(13) having a poor functional result. Forty-two patients (47 limbs) initially presented with an insensate foot. At final follow up (mean 25.4 months), 89%(42 limbs) had a return of protective plantar sensation. Overall, 9 patients were able to return to full military duty (P2), with 45 deemed unfit for military service (P0 or P8).

This study demonstrates that the majority of combat PNI will show some functional recovery. Adherence to the principles of war surgery to ensure that the wound is clear of infection and associated vascular and skeletal injuries are promptly treated will provide the optimal environment for nerve recovery. Although neuropathic pain affects a significant proportion of casualties, pharmacological and surgical intervention can alleviate the majority of symptoms. Finally, the presence of an insensate limb at initial surgery, should not be used as a marker of limb viability. The key to recovery of the PNI patient lies in a multi-disciplinary approach. Essential to this is regular surgical review to assess progress and to initiate prompt surgical intervention when needed. This approach allows early determination of prognosis, which is of huge value to the rehabilitating patient psychologically, and to the whole rehabilitation team.

The outcomes of 261 nerve injuries in 100 patients were graded good in 173 cases (66%), fair in 70 (26.8%) and poor in 18 (6.9%) at the final review (median 28.4 months (1.3 to 64.2)). The initial grades for the 42 sutures and graft were 11 good, 14 fair and 17 poor. After subsequent revision repairs in seven, neurolyses in 11 and free vascularised fasciocutaneous flaps in 11, the final grades were 15 good, 18 fair and nine poor. Pain was relieved in 30 of 36 patients by nerve repair, revision of repair or neurolysis, and flaps when indicated. The difference in outcome between penetrating missile wounds and those caused by explosions was not statistically significant; in the latter group the onset of recovery from focal conduction block was delayed (mean 4.7 months (2.5 to 10.2) vs 3.8 months (0.6 to 6); p = 0.0001). A total of 42 patients (47 lower limbs) presented with an insensate foot. By final review (mean 27.4 months (20 to 36)) plantar sensation was good in 26 limbs (55%), fair in 16 (34%) and poor in five (11%). Nine patients returned to full military duties, 18 to restricted duties, 30 to sedentary work, and 43 were discharged from military service. Effective rehabilitation must be early, integrated and vigorous. The responsible surgeons must be firmly embedded in the process, at times exerting leadership.

We describe 261 peripheral nerve injuries sustained in war by 100 consecutive service men and women injured in Iraq and Afghanistan. Their mean age was 26.5 years (18.1 to 42.6), the median interval between injury and first review was 4.2 months (mean 8.4 months (0.36 to 48.49)) and median follow-up was 28.4 months (mean 20.5 months (1.3 to 64.2)). The nerve lesions were predominantly focal prolonged conduction block/neurapraxia in 116 (45%), axonotmesis in 92 (35%) and neurotmesis in 53 (20%) and were evenly distributed between the upper and the lower limbs. Explosions accounted for 164 (63%): 213 (82%) nerve injuries were associated with open wounds. Two or more main nerves were injured in 70 patients. The ulnar, common peroneal and tibial nerves were most commonly injured. In 69 patients there was a vascular injury, fracture, or both at the level of the nerve lesion. Major tissue loss was present in 50 patients: amputation of at least one limb was needed in 18. A total of 36 patients continued in severe neuropathic pain.

This paper outlines the methods used in the assessment of these injuries and provides information about the depth and distribution of the nerve lesions, their associated injuries and neuropathic pain syndromes.

A 60-year-old man developed severe neuropathic pain and foot-drop in his left leg following resurfacing arthroplasty of the left hip. The pain was refractory to all analgesics for 16 months. At exploration, a PDS suture was found passing through the sciatic nerve at several points over 6 cm and terminating in a large knot. After release of the suture and neurolysis there was dramatic and rapid improvement of the neuropathic pain and of motor function.

This case represents the human equivalent of previously described nerve ligation in an animal model of neuropathic pain. It emphasises that when neuropathic pain is present after an operation, the nerve related to the symptoms must be inspected, and that removal of a suture or irritant may lead to relief of pain, even after many months.

We studied 27 patients with low back pain and unilateral L5 or S1 spinal nerve root pain. Significant radiological changes were restricted to the symptomatic root level, when compared with controls. Low back and leg pain were graded on a visual analogue scale. Dermatomal quantitative sensory tests revealed significant elevations of warm, cool and touch perception thresholds in the affected dermatome, compared with controls. These elevations correlated with root pain (warm v L5 root pain; r = 0.88, p < 0.0001), but not with back pain. Low back pain correlated with restriction of anteroposterior spinal flexion (p = 0.02), but not with leg pain.

A subset of 16 patients underwent decompressive surgery with improvement of pain scores, sensory thresholds and spinal mobility. A further 14 patients with back pain, multilevel nerve root symptoms and radiological changes were also studied. The only correlation found was of low back pain with spinal movement (p < 0.002). We conclude that, in patients with single level disease, dermatomal sensory threshold elevation and restriction of spinal movement are independent correlates of sciatica and low back pain.

We describe seven cases of permanent neurological damage following interscalene block used in post-operative analgesia after operations at the shoulder. MRI, Nerve Conduction Studies and Quantitative assessments of function confirmed that in all there was infarction of the anterior spinal cord, resulting in a spinothalamic and corticospinal tract defect especially at segments C7, C8 and T1. We think that these lesions were caused by injury to radicular arteries. Domisse has demonstrated the anatomy of the radicular vessels joining the anterior spinal artery to supply the anterior two thirds of the cord. They are branches of the vertebral, ascending cervical and deep cervical arteries which pass through the inter-vertebral foramina with the C7, C8 and T1 roots predominantly. Chakravorty has shown that radicular vessels contribute to the blood supply of the lower cervical cord. Injury to them can cause ischaemia, leading to Anterior Spinal Artery Syndrome. We suggest tamponade of the radicular vessels by infusion of fluid under pressure deep to the prevertebral fascia as the main mechanism but neurotoxicity and vasospasm can be other possible explanations.

In a second group there was an additional interference with the vertebral artery presenting with transient bulbar and cranial nerve symptoms. We had 2 patients with such combined lesions. Complications of interscalene blocks are well documented but most are reversible and transient. In our cases the damage has been permanent and disabling. The innervation of the gleno-humeral joint is largely through the 4th, 5th and 6th cervical nerves and we suggest more appropriate placing of the blockade should be adapted and use of this technique for post-operative analgesia should be abandoned.

Study Design: To examine the innervation of the lumbar spine from patients with lower back pain, and spinal nerve roots from patients with traumatic brachial plexus injuries.

Objectives: To demonstrate the presence of nerve fibres in lumbar spine structures and spinal nerve roots, and determine whether they express the sensory neuronespecific sodium channels SNS/PN3 and NaN/SNS2.

Summary of background data: The anatomical and molecular basis of low back pain and sciatica is poorly understood. Previous studies have demonstrated sensory nerves in facet joint capsule and prolapsed intervertebral disc, but not in ligamentum flavum. The voltagegated sodium channels SNS/PN3 and NaN/SNS2 are expressed by sensory neurones which mediate pain, but their presence in the lumbar spine is unknown.

Methods: Tissue samples (ligamentum flavum n=32; facet joint capsule n=20; intervertebral disc n=15; spinal roots n=8) were immunostained with specific antibodies to protein gene product (PGP) 9.5, a pan-neuronal marker, SNS/PN3 and NaN/SNS2.

Results: PGP 9.5-immunoreactive nerve fibres were detected in 72% of ligamentum flavum and 70% of facet joint capsule but only 20% of intervertebral disc specimens. SNS/PN3-and NaN/SNS2-positive fibres were detected in 28% and 3% of ligamentum flavum and 25% and 15% of facet joint capsule specimens respectively. Numerous SNS/PN3 and NaN/SNS2-positive fibres were found in the acutely injured spinal roots, and some were still present in dorsal roots in the chronic state.

Conclusions: SNS/PN3 and NaN/SNS2-immunoreactivity is present in a subset of nerve fibres in lumbar spine structures, including ligamentum flavum and injured spinal roots. This is the first time that sensory nerve fibres have been demonstrated in the ligamentum flavum, and this raises the possibility that, contrary to the conclusions of previous studies, this unique ligament may be capable of nociception. Selective SNS/PN3 and NaN/ SNS2 blocking agents may provide new effective therapy for back pain and sciatica, with fewer side effects. Other novel ion channels are being studied in these tissues.

We performed intercostal nerve transfer in 19 patients to relieve pain from preganglionic injury to the brachial plexus. The procedure was successful in 16 patients at a mean of 28.6 months (12 to 68) after the injury.