Aims. This study aimed to use intraoperative free electromyography to examine how the placement of a retractor at different positions along the anterior acetabular wall may affect the femoral nerve during total hip arthroplasty (THA) when undertaken using the direct anterior approach (THA-DAA). Methods. Intraoperative free electromyography was performed during primary THA-DAA in 82 patients (94 hips). The highest position of the anterior acetabular wall was defined as the “12 o’clock” position (middle position) when the patient was in supine position. After exposure of the acetabulum, a retractor was sequentially placed at the ten, 11, 12, one, and two o’clock positions (right hip; from superior to inferior positions). Action potentials in the femoral nerve were monitored with each placement, and the incidence of positive reactions (defined as explosive, frequent, or continuous action potentials, indicating that the nerve was being compressed) were recorded as the primary outcome. Secondary outcomes included the incidence of positive reactions caused by removing the femoral head, and by placing a retractor during femoral exposure; and the incidence of femoral nerve palsy, as detected using manual testing of the strength of the quadriceps muscle. Results. Positive reactions were significantly less frequent when the retractor was placed at the ten (15/94; 16.0%), 11 (12/94; 12.8%), or 12 o’clock positions (19/94; 20.2%), than at the one (37/94; 39.4%) or two o’clock positions (39/94; 41.5%) (p < 0.050). Positive reactions also occurred when the femoral head was removed (28/94; 29.8%), and when a retractor was placed around the proximal femur (34/94; 36.2%) or medial femur (27/94; 28.7%) during femoral exposure. After surgery, no patient had reduced strength in the quadriceps muscle. Conclusion. Placing the anterior acetabular retractor at the one or two o’clock positions (right hip; inferior positions) during THA-DAA can increase the rate of electromyographic signal changes in the femoral nerve. Thus, placing a retractor in these positions may increased the risk of the development of a femoral nerve palsy. Cite this article: Bone Joint J 2022;104-B(2):193–199

1. Telemetering electromyography has been used to investigate the pattern of activity of certain muscles of the lower limb and back while the subjects walked up and down stairs. 2. During walking up and down stairs each limb has a supporting and swinging phase in each complete step. 3. Walking up stairs revealed the following facts. Firstly, raising the body on to the stair above is brought about by the contraction of the soleus, quadriceps femoris, hamstrings and gluteus maximus; the gluteus medius at the same time prevents the body falling on to the unsupported side. Secondly, the tibialis anterior dorsiflexes the foot during the swinging phase and helps the limb to clear the stair on which the supporting limb is placed. Thirdly, the hamstrings flex the leg at the knee in the early part of the swinging phase and control the terminal part of extension at the knee at the end of this phase. Fourthly, both erectores spinae contract twice in each step and control the forward bending of the body at the vertebral column. 4. Walking down stairs revealed the following. Firstly, the body is lowered on to the stair below by the controlled lengthening of the soleus and quadriceps femoris; the gluteus medius at the same time prevents the body from falling on to the unsupported side. Secondly, the tibialis anterior inverts the foot at the beginning of the supporting phase as the toe is placed on the stair below and dorsiflexes the foot in the middle of the swinging phase. Thirdly, the hamstrings control the extension of the leg at the knee during the middle of the swinging phase. Fourthly, both erectores spinae contract twice in each step and prevent forward bending of the trunk at the vertebral column

Aims

This study aimed to explore whether intraoperative nerve monitoring can identify risk factors and reduce the incidence of nerve injury in patients with high-riding developmental dysplasia.

1. The deep posterior muscles of the neck are innervated by the posterior branches of spinal nerves, which branch off immediately after the root emerges from the intervertebral foramen. Electromyographic examination of these muscles permits a differential diagnosis to be made between intraforaminal and extraforaminal brachial plexus lesions.

2. The earlier diagnosis and prognosis thus achieved permit definitive treatment, in particular suture of the torn nerve trunks in recent extraforaminal cases.

We investigated the predictive value of intra-operative neurophysiological investigations in obstetric brachial plexus injuries. Between January 2005 and June 2011 a total of 32 infants of 206 referred to our unit underwent exploration of the plexus, including neurolysis. The findings from intra-operative electromyography, sensory evoked potentials across the lesion and gross muscular response to stimulation were evaluated. A total of 22 infants underwent neurolysis alone and ten had microsurgical reconstruction. Of the former, one was lost to follow-up, one had glenoplasty and three had subsequent nerve reconstructions. Of the remaining 17 infants with neurolysis, 13 (76%) achieved a modified Mallet score > 13 at a mean age of 3.5 years (0.75 to 6.25). Subluxation or dislocation of the shoulder is a major confounding factor. The positive predictive value and sensitivity of the intra-operative EMG for C5 were 100% and 85.7%, respectively, in infants without concurrent shoulder pathology. The positive and negative predictive values, sensitivity and specificity of the three investigations combined were 77%, 100%, 100% and 57%, respectively. In all, 20 infants underwent neurolysis alone for C6 and three had reconstruction. All of the former and one of the latter achieved biceps function of Raimondi grade 5. The positive and negative predictive values, sensitivity and specificity of electromyography for C6 were 65%, 71%, 87% and 42%, respectively. Our method is effective in evaluating the prognosis of C5 lesion. Neurolysis is preferred for C6 lesions. Cite this article: Bone Joint J 2013;95-B:699–705

Aims. Improvements in the evaluation of outcomes following peripheral nerve injury are needed. Recent studies have identified muscle fatigue as an inevitable consequence of muscle reinnervation. This study aimed to quantify and characterize muscle fatigue within a standardized surgical model of muscle reinnervation. Patients and Methods. This retrospective cohort study included 12 patients who underwent Oberlin nerve transfer in an attempt to restore flexion of the elbow following brachial plexus injury. There were ten men and two women with a mean age of 45.5 years (27 to 69). The mean follow-up was 58 months (28 to 100). Repeated and sustained isometric contractions of the elbow flexors were used to assess fatigability of reinnervated muscle. The strength of elbow flexion was measured using a static dynamometer (KgF) and surface electromyography (sEMG). Recordings were used to quantify and characterize fatigability of the reinnervated elbow flexor muscles compared with the uninjured contralateral side. Results. The mean peak force of elbow flexion was 7.88 KgF (. sd. 3.80) compared with 20.65 KgF (. sd . 6.88) on the contralateral side (p < 0.001). Reinnervated elbow flexor muscles (biceps brachialis) showed sEMG evidence of fatigue earlier than normal controls with sustained (60-second) isometric contraction. Reinnervated elbow flexor muscles also showed a trend towards a faster twitch muscle fibre type. Conclusion. The assessment of motor outcomes must involve more than peak force alone. Reinnervated muscle shows a shift towards fast twitch fibres following reinnervation with an earlier onset of fatigue. Our findings suggest that fatigue is a clinically relevant characteristic of reinnervated muscle. Adoption of these metrics into clinical practice and the assessment of outcome could allow a more meaningful comparison to be made between differing forms of treatment and encourage advances in the management of motor recovery following nerve transfer. Cite this article: Bone Joint J 2019;101-B:867–871

Peripheral nerve injury is an uncommon but serious complication of hip surgery that can adversely affect the outcome. Several studies have described the use of electromyography and intra-operative sensory evoked potentials for early warning of nerve injury. We assessed the results of multimodal intra-operative monitoring during complex hip surgery. We retrospectively analysed data collected between 2001 and 2010 from 69 patients who underwent complex hip surgery by a single surgeon using multimodal intra-operative monitoring from a total pool of 7894 patients who underwent hip surgery during this period. In 24 (35%) procedures the surgeon was alerted to a possible lesion to the sciatic and/or femoral nerve. Alerts were observed most frequently during peri-acetabular osteotomy. The surgeon adapted his approach based on interpretation of the neurophysiological changes. From 69 monitored surgical procedures, there was only one true positive case of post-operative nerve injury. There were no false positives or false negatives, and the remaining 68 cases were all true negative. The sensitivity for predicting post-operative nerve injury was 100% and the specificity 100%. We conclude that it is possible and appropriate to use this method during complex hip surgery and it is effective for alerting the surgeon to the possibility of nerve injury

Aims. Our aim was to describe the atypical pattern of increased fatty degeneration in the infraspinatus muscle compared with the supraspinatus in patients with a massive rotator cuff tear. We also wished to describe the nerve conduction and electromyography findings in these patients. Patients and Methods. A cohort of patients undergoing surgery for a massive rotator cuff tear was identified and their clinical records obtained. Their MRI images were reviewed to ascertain the degree of retraction of the torn infraspinatus and supraspinatus muscles, and the degree of fatty degeneration in both muscles was recorded. Nerve conduction studies were also performed in those patients who showed more degeneration in the infraspinatus than in the supraspinatus. Results. Out of a total of 396 patients who underwent surgery for a massive rotator cuff tear between 2006 and 2015, 35 who had more severe fatty degeneration in the infraspinatus than in the supraspinatus were identified. There were 13 men and 22 women. Their mean age was 67.2 years (56 to 81). A total of 20 (57%) had grade 4 fatty degeneration as classified by Fuchs et al, in the infraspinatus. Patte grade 3 muscle retraction was seen in 25 patients (71%). In all, eight patients (23%) had abnormal nerve conduction studies. The mean retraction of the infraspinatus was 3.6 cm (2.1 to 4.8) in patients with more severe fatty degeneration in the infraspinatus, versus 3.0 cm (1.7 to 5.5) in those with more severe degeneration in the supraspinatus (p = 0.003). The retraction ratios were 0.98 (0.61 to 1.57) and 0.77 (0.38 to 1.92), respectively (p < 0.001). Conclusion. Fatty degeneration affecting the infraspinatus more than the supraspinatus may be, in the context of a massive rotator cuff tear, due to entrapment of the suprascapular nerve at the spinoglenoid notch. Cite this article: Bone Joint J 2016;98-B:1505–9

We investigated the detailed anatomy of the gluteus maximus, gluteus medius and gluteus minimus and their neurovascular supply in 22 hips in 11 embalmed adult Caucasian human cadavers. This led to the development of a surgical technique for an extended posterior approach to the hip and pelvis that exposes the supra-acetabular ilium and preserves the glutei during revision hip surgery. Proximal to distal mobilisation of the gluteus medius from the posterior gluteal line permits exposure and mobilisation of the superior gluteal neurovascular bundle between the sciatic notch and the entrance to the gluteus medius, enabling a wider exposure of the supra-acetabular ilium. This technique was subsequently used in nine patients undergoing revision total hip replacement involving the reconstruction of nine Paprosky 3B acetabular defects, five of which had pelvic discontinuity. Intra-operative electromyography showed that the innervation of the gluteal muscles was not affected by surgery. Clinical follow-up demonstrated good hip abduction function in all patients. These results were compared with those of a matched cohort treated through a Kocher–Langenbeck approach. Our modified approach maximises the exposure of the ilium above the sciatic notch while protecting the gluteal muscles and their neurovascular bundle. Cite this article: Bone Joint J 2014;96-B:48–53

Aims

Conventional patient-reported surveys, used for patients undergoing total hip arthroplasty (THA), are limited by subjectivity and recall bias. Objective functional evaluation, such as gait analysis, to delineate a patient’s functional capacity and customize surgical interventions, may address these shortcomings. This systematic review endeavours to investigate the application of objective functional assessments in appraising individuals undergoing THA.

In a 41-year-old man, right-sided infraspinatus muscle weakness was associated with compression of the suprascapular nerve caused by a spinoglenoid ganglion cyst. The lesion was confirmed using electromyography and MRI. In addition, arthroscopy showed an incomplete discoid labrum. The free inner edge of the labrum was removed as in a meniscectomy of a discoid meniscus in the knee joint. Arthroscopic decompression of the cyst was performed through a juxtaglenoid capsulotomy which was left open. Neurological function recovered completely

Aims

Children with spinal dysraphism can develop various musculoskeletal deformities, necessitating a range of orthopaedic interventions, causing significant morbidity, and making considerable demands on resources. This systematic review aimed to identify what outcome measures have been reported in the literature for children with spinal dysraphism who undergo orthopaedic interventions involving the lower limbs.

Aims

The aim of this study was to reassess the rate of neurological, psoas-related, and abdominal complications associated with L4-L5 lateral lumbar interbody fusion (LLIF) undertaken using a standardized preoperative assessment and surgical technique.

Injury to the sciatic nerve is one of the more serious complications of acetabular fracture and traumatic dislocation of the hip, both in the short and long term. We have reviewed prospectively patients, treated in our unit, for acetabular fractures who had concomitant injury to the sciatic nerve, with the aim of predicting the functional outcome after these injuries. Of 136 patients who underwent stabilisation of acetabular fractures, there were 27 (19.9%) with neurological injury. At initial presentation, 13 patients had a complete foot-drop, ten had weakness of the foot and four had burning pain and altered sensation over the dorsum of the foot. Serial electromyography (EMG) studies were performed and the degree of functional recovery was monitored using the grading system of the Medical Research Council. In nine patients with a foot-drop, there was evidence of a proximal acetabular (sciatic) and a distal knee (neck of fibula) nerve lesion, the double-crush syndrome. At the final follow-up, clinical examination and EMG studies showed full recovery in five of the ten patients with initial muscle weakness, and complete resolution in all four patients with sensory symptoms (burning pain and hyperaesthesia). There was improvement of functional capacity (motor and sensory) in two patients who presented initially with complete foot-drop. In the remaining 11 with foot-drop at presentation, including all nine with the double-crush lesion, there was no improvement in function at a mean follow-up of 4.3 years

Aims

The aim of this study was to review the current evidence surrounding curve type and morphology on curve progression risk in adolescent idiopathic scoliosis (AIS).

1. A case of ulnar nerve compression at the wrist caused by rheumatoid arthritis producing motor and sensory changes is presented. 2. The diagnosis from compression at the elbow can be determined by electromyography. 3. It may be that lesions of the deep branch leading to motor changes only occur in rheumatoid arthritis more often than is suspected, their effects being hidden by the concomitant disease and its associated muscle wasting

1. In ten healthy young men an experimental paralysis of the supraspinatus muscle was induced with the aid of Xylocaine injected in or near the suprascapular nerve. 2. The completeness of the paralysis was checked by electromyography. 3. With the supraspinatus muscle completely eliminated, all subjects could move the arm against gravity through its full range in the shoulder joint, though the force and the power of endurance during abduction were diminished. 4. It is concluded that the role of the supraspinatus muscle is of a quantitative nature only

The role of muscle function in the aetiology of recurrent dislocation of the patella has been examined. Eleven of the 12 patients we studied had joint hypermobility. Muscle biopsies from eight of nine patients treated by surgery had a predominance of abnormal Type 2C fibres, and three of six patients whose quadriceps muscles were studied by electromyography also had abnormal results. Our preliminary findings suggest that there may be a primary muscular defect in many cases of recurrent dislocation of the patella

We report the case of a 59-year-old man with severe knee pain and inability to flex his toes or invert his plantar flexed foot after an external rotation injury to his knee. MRI showed rupture of the popliteus with a haematoma compressing the neurovascular bundle in the proximal calf, and electromyography demonstrated signs of an axonotmesis of the posterior tibial nerve. There was progressive nerve recovery over 24 weeks. Isolated rupture of the popliteus should be considered in any patient with an acute haemarthrosis, lateral tenderness and a stable knee, especially after an external rotation injury

We have reviewed 10 patients treated for anterior tarsal tunnel syndrome produced by compression of the deep peroneal nerve or its branches, and we have studied the anatomy of the tunnel in 25 adult feet. The causes of onset of the syndrome included contusion of the dorsum of the foot, tight shoe laces, talonavicular osteophytosis, ganglion, and pes cavus. The clinical signs were often diagnostic but electromyography was helpful. Operative decompression in nine feet of eight patients gave successful results at 1.5 to 4 years follow-up

Traction injury to the sciatic nerve can occur during hamstring lengthening. The aim of this study was to monitor the influence of hamstring lengthening on conduction in the sciatic nerve using evoked electromyography (EMG). Ten children with spastic cerebral palsy underwent bilateral distal hamstring lengthening. Before lengthening, the evoked potential was recorded with the patient prone. During lengthening, it was recorded with the knee flexed to 90°, 60° and 30°, and at the end of lengthening with the hip and knee extended. In all patients, the amplitude of the evoked EMG gradually decreased with increasing lengthening. The mean decrease with the knee flexed to 60° was 34% (10 to 77), and to 30°, 86% (52 to 98) compared with the pre-lengthening amplitude. On hip extension at the end of the lengthening procedure, the EMG returned to the pre-lengthening level. Monitoring of the evoked EMG potential of the sciatic nerve during and after hamstring lengthening, may be helpful in preventing traction injury

Twenty-two patients with ulnar nerve palsy at the elbow, confirmed by electromyography, were treated by a night splint which prevented flexion of the elbow beyond 60 degrees. The splint was worn all night regularly for at least six months. At a mean follow-up of 11.3 months, 17 patients had clinical and electromyographic assessment and five were contacted by telephone. There was improvement in the symptoms in every patient, including three who had failed to respond to surgical decompression. There was electromyographic improvement in 16 of the 17 patients re-examined at follow-up. The mean improvement in motor nerve conduction velocity was 6.5 m/s and in sensory nerve conduction velocity 9.5 m/s. The efficacy of this treatment suggests that nocturnal elbow flexion is an important cause of ulnar nerve lesions at the elbow

Spinal accessory nerve palsy leads to painful disability of the shoulder, carrying an uncertain prognosis. We reviewed the long-term outcome in 16 patients who were treated for pain, weakness of active elevation and asymmetry of the shoulder and the neck due to chronic paralysis of the trapezius muscle, as a result of nerve palsy. Of four patients who were treated conservatively, none regained satisfactory function, although two became pain-free. The other 12 patients were treated operatively with transfer of the levator scapulae to the acromion and the rhomboid muscles to the infraspinatus fossa (the Eden-Lange procedure). At a mean follow-up of 32 years, the clinical outcome of the operatively treated patients was excellent in nine, fair in two, and poor in one patient, as determined by the Constant score. Pain was adequately relieved in 11 and overhead function was restored in nine patients. Pre-operative electromyography had been carried out in four patients. In two, who eventually had a poor outcome, a concomitant long thoracic and dorsal scapular nerve lesion had been present. The Eden-Lange procedure gives very satisfactory long-term results for the treatment of isolated paralysis of trapezius. In the presence of an additional serratus anterior palsy or weak rhomboid muscles, the procedure is less successful in restoring shoulder function

Nerve injury is a rare complication of total hip replacement which may be related to the exposure used for the operation. The posterior approach is traditionally associated with injury to the sciatic nerve. We have compared the incidence of nerve injury after primary total hip replacement (THR) using either a posterior or a direct lateral approach. We studied 42 consecutive patients undergoing primary total hip replacement. The surgeons used a posterior (22 patients) or direct lateral (20 patients) approach in accordance with their normal practice. The obturator, femoral, posterior tibial and common peroneal nerves were assessed clinically and electrophysiologically by electromyography (EMG) and measurement of the velocity of nerve conduction before operation and at four weeks after. All patients were free from symptoms of nerve injury after operation but five lesions were identified in four patients by the electrophysiological studies; the obturator nerve was involved in two, the femoral in one, the common peroneal in one and the posterior tibial in one. All these injuries occurred using the lateral approach. Clinical assessment alone underestimates the incidence of nerve injury complicating THR. Our study does not confirm the association of nerve injury with the posterior approach which had been described previously

1. Experience with a refined type of implantable electrode for the myo-electric control of externally powered prostheses is reported. 2. The electrodes are externally energised by electromagnetic induction and therefore do not contain any battery cells. The myo-potentials are transmitted in frequency-modulated form and detected by a receiver placed on the skin. The implantable electrode, measuring 5x11x4 millimetres, is encapsulated in epoxy resin. 3. Six electrodes have been implanted in the forearms of two normal subjects and two below-elbow amputees. The time of implantation ranged from three to fifteen months. Macroscopically, a fibrous capsule developed around the electrodes. Histological examination showed a capsule of granulation tissue of varying thickness with slight inflammatory reaction and foreign-body giant cells. 4. In all cases except one the signals received have been of high quality as ascertained by conventional electromyography and frequency analysis. There has been no significant deterioration in signal quality during the follow-up periods. 5. The major source of failure was fatigue fracture of the gold wires making contact with the body tissues. In one case, however, the electrode was still functioning normally at the time of removal fifteen months after insertion. 6. The patients have not been inconvenienced either by the operative procedures or by the presence of the electrodes in the tissues

The etiological factors concerned in paralytic scoliosis are complex. Four main types of paralytic scoliosis can be recognised. 1. The general C-curve due to the body's anatomical attempt to shift its centre of gravity towards the weaker side. Vertebral rotation is not usually marked. This type usually occurs when patients with relatively slight paralysis have been allowed up too early ; it does not usually progress to severe deformity but may occasionally do so, gradually changing into Type 2. This type usually responds well to a period of rest and muscle redevelopment in recumbency. It also responds favourably to correction and fusion because correction is easy and there is little tendency to deterioration. Many of the "successes" of correction and fusion are in this class—almost equal success would often have been gained without "correction." The spine is slightly, but not very, unstable and a relatively localised fusion will give the little extra support that is needed. 2. The "general collapse" type of curve due to extensive spinal weakness. This is the type in which simple head suspension produces marked correction. Rotation is moderate. Provided the patient's general condition is satisfactory extensive spinal fusion is usually the best treatment and produces gratifying improvement. 3. The primary lumbar curve due to a combination of pelvic obliquity, extraspinal imbalance and imbalance of the deep rotator muscles. Rotation is usually marked. Treatment must include the correction of all these factors. In mild cases correction of the pelvic obliquity is enough, but in marked cases the spine must also be corrected. The disability from a lumbar paralytic scoliosis is much greater than that from a lumbar idiopathic scoliosis of the same degree; so correction is necessary in this type. Correction in a Risser-type jacket is often inadequate and recourse to operative correction is usually required. 4. The primary thoracic curve—often associated with weakness of the scapular muscles. The indications for and methods of treatment are practically the same as in primary idiopathic thoracic curves. These curves tend to be progressive and uncompensated. Although the most popular treatment is correction and fusion, wedge osteotomy of the spine gives better correction in intractable cases. The main need is for further investigation into the etiology of paralytic scoliosis so that adequate preventive measures may be undertaken at an early stage. It is essential that every child who contracts poliomyelitis should have his back muscles examined before he gets up. If there is any suggestion of scoliosis further investigations including radiography and electromyography are essential

Aims

To report the surgical outcome of patients with severe Scheuermann’s kyphosis treated using a consistent technique and perioperative management.

Deep gluteal syndrome is an increasingly recognized disease entity, caused by compression of the sciatic or pudendal nerve due to non-discogenic pelvic lesions. It includes the piriformis syndrome, the gemelli-obturator internus syndrome, the ischiofemoral impingement syndrome, and the proximal hamstring syndrome. The concept of the deep gluteal syndrome extends our understanding of posterior hip pain due to nerve entrapment beyond the traditional model of the piriformis syndrome. Nevertheless, there has been terminological confusion and the deep gluteal syndrome has often been undiagnosed or mistaken for other conditions. Careful history-taking, a physical examination including provocation tests, an electrodiagnostic study, and imaging are necessary for an accurate diagnosis.

After excluding spinal lesions, MRI scans of the pelvis are helpful in diagnosing deep gluteal syndrome and identifying pathological conditions entrapping the nerves. It can be conservatively treated with multidisciplinary treatment including rest, the avoidance of provoking activities, medication, injections, and physiotherapy.

Endoscopic or open surgical decompression is recommended in patients with persistent or recurrent symptoms after conservative treatment or in those who may have masses compressing the sciatic nerve.

Many physicians remain unfamiliar with this syndrome and there is a lack of relevant literature. This comprehensive review aims to provide the latest information about the epidemiology, aetiology, pathology, clinical features, diagnosis, and treatment.

Cite this article: Bone Joint J 2020;102-B(5):556–567.

Abstract

Nerve transfer has become a common and often effective reconstructive strategy for proximal and complex peripheral nerve injuries of the upper limb. This case-based discussion explores the principles and potential benefits of nerve transfer surgery and offers in-depth discussion of several established and valuable techniques including: motor transfer for elbow flexion after musculocutaneous nerve injury, deltoid reanimation for axillary nerve palsy, intrinsic re-innervation following proximal ulnar nerve repair, and critical sensory recovery despite non-reconstructable median nerve lesions.

In the time since Letournel popularised the surgical treatment of acetabular fractures, more than 25 years ago, there have been many changes within the field, related to patients, surgical technique, implants and post-operative care. However, the long-term outcomes appear largely unchanged. Does this represent stasis or have the advances been mitigated by other negative factors? In this article we have attempted to document the recent changes within the surgery of patients with a fracture involving the acetabulum, outline contemporary management, and identify the major problem areas where further research is most needed.

Cite this article: Bone Joint J 2017;99-B:1125–31

Aims

The most effective surgical approach for total hip arthroplasty (THA) remains controversial. The direct anterior approach may be associated with a reduced risk of dislocation, faster recovery, reduced pain and fewer surgical complications. This systematic review aims to evaluate the current evidence for the use of this approach in THA.

Nerve palsy is a well-described complication following total hip arthroplasty, but is highly distressing and disabling. A nerve palsy may cause difficulty with the post-operative rehabilitation, and overall mobility of the patient. Nerve palsy may result from compression and tension to the affected nerve(s) during the course of the operation via surgical manipulation and retractor placement, tension from limb lengthening or compression from post-operative hematoma. In the literature, hip dysplasia, lengthening of the leg, the use of an uncemented femoral component, and female gender are associated with a greater risk of nerve palsy. We examined our experience at a high-volume, tertiary care referral centre, and found an overall incidence of 0.3% out of 39 056 primary hip arthroplasties. Risk factors found to be associated with the incidence of nerve palsy at our institution included the presence of spinal stenosis or lumbar disc disease, age younger than 50, and smoking. If a nerve palsy is diagnosed, imaging is mandatory and surgical evacuation or compressive haematomas may be beneficial. As palsies are slow to recover, supportive care such as bracing, therapy, and reassurance are the mainstays of treatment.

Cite this article: Bone Joint J 2017;99-B(1 Supple A):46–9.

The aim of this study was to evaluate the feasibility of using the intact S1 nerve root as a donor nerve to repair an avulsion of the contralateral lumbosacral plexus. Two cohorts of patients were recruited. In cohort 1, the L4–S4 nerve roots of 15 patients with a unilateral fracture of the sacrum and sacral nerve injury were stimulated during surgery to establish the precise functional distribution of the S1 nerve root and its proportional contribution to individual muscles. In cohort 2, the contralateral uninjured S1 nerve root of six patients with a unilateral lumbosacral plexus avulsion was transected extradurally and used with a 25 cm segment of the common peroneal nerve from the injured leg to reconstruct the avulsed plexus.

The results from cohort 1 showed that the innervation of S1 in each muscle can be compensated for by L4, L5, S2 and S3. Numbness in the toes and a reduction in strength were found after surgery in cohort 2, but these symptoms gradually disappeared and strength recovered. The results of electrophysiological studies of the donor limb were generally normal.

Severing the S1 nerve root does not appear to damage the healthy limb as far as clinical assessment and electrophysiological testing can determine. Consequently, the S1 nerve can be considered to be a suitable donor nerve for reconstruction of an avulsed contralateral lumbosacral plexus.

Cite this article: Bone Joint J 2015; 97-B:358–65.

Aims

The aim of this study was to analyse human muscle tissue before and after rotator cuff repair to look for evidence of regeneration, and to characterise the changes seen in the type of muscle fibre.

A 25-year-old male weightlifter felt increasing intractable low back pain during training but denied any acute injury. The physical examination, blood parameters, radiographs and MRI were unremarkable. He had been treated non-operatively by various means, with only temporary relief. The pressures in the lumbar paraspinal compartment were abnormally high and he was treated by surgical decompression. This gave rapid relief, he returned to training, and one year later the pain had not recurred.

The aim of this study was to examine the loading of the other joints of the lower limb in patients with unilateral osteoarthritis (OA) of the knee. We recruited 20 patients with no other symptoms or deformity in the lower limbs from a consecutive cohort of patients awaiting knee replacement. Gait analysis and electromyographic recordings were performed to determine moments at both knees and hips, and contraction patterns in the medial and lateral quadriceps and hamstrings bilaterally. The speed of gait was reduced in the group with OA compared with the controls, but there were only minor differences in stance times between the limbs. Patients with OA of the knee had significant increases in adduction moment impulse at both knees and the contralateral hip (adjusted p-values: affected knee: p < 0.01, unaffected knee p = 0.048, contralateral hip p = 0.03), and significantly increased muscular co-contraction bilaterally compared with controls (all comparisons for co-contraction, p < 0.01).

The other major weight-bearing joints are at risk from abnormal biomechanics in patients with unilateral OA of the knee.

Cite this article: Bone Joint J 2013;95-B:348–53.

Aims

Between 2002 and 2011, 81 patients with a traumatic total brachial plexus injury underwent reconstruction by double free muscle transfer (DFMT, 47 cases), single muscle transfer (SMT, 16 cases) or nerve transfers (NT, 18 cases).

The aim of this cadaver study was to identify the change in position of the sciatic nerve during arthroplasty using the posterior surgical approach to the hip. We investigated the position of the nerve during this procedure by dissecting 11 formalin-treated cadavers (22 hips: 12 male, ten female). The distance between the sciatic nerve and the femoral neck was measured before and after dislocation of the hip, and in positions used during the preparation of the femur. The nerve moves closer to the femoral neck when the hip is flexed to > 30° and internally rotated to 90° (90° IR). The mean distance between the nerve and femoral neck was 43.1 mm (standard deviation (sd) 8.7) with the hip at 0° of flexion and 90° IR; this significantly decreased to a mean of 36.1 mm (sd 9.5), 28.8 mm (sd 9.8) and 19.1 mm (sd 9.7) at 30°, 60° and 90° of hip flexion respectively (p < 0.001). In two hips the nerve was in contact with the femoral neck when the hip was flexed to 90°.

This study demonstrates that the sciatic nerve becomes closer to the operative field during hip arthroplasty using the posterior approach with progressive flexion of the hip.

Cite this article: Bone Joint J 2015;97-B:1056–62.

The widespread use of MRI has revolutionised the diagnostic process for spinal disorders. A typical protocol for spinal MRI includes T1 and T2 weighted sequences in both axial and sagittal planes. While such an imaging protocol is appropriate to detect pathological processes in the vast majority of patients, a number of additional sequences and advanced techniques are emerging. The purpose of the article is to discuss both established techniques that are gaining popularity in the field of spinal imaging and to introduce some of the more novel ‘advanced’ MRI sequences with examples to highlight their potential uses.

Cite this article: Bone Joint J 2015;97-B:1683–92.

Neuralgic amyotrophy is an uncommon condition characterised by the acute onset of severe pain in the shoulder and arm, followed by weakness and atrophy of the affected muscles, and sensory loss as the pain subsides. The diversity of its clinical manifestations means that it may present to a variety of different specialties within medicine. This article describes the epidemiology, aetiopathogenesis, clinical features, differential diagnoses, investigations, treatment, course and prognosis of the condition.

We retrospectively studied the possibility that direct trauma to the biceps muscle might be the cause of poor elbow flexion and supination in 18 consecutive children with birth lesions of the brachial plexus who had delayed or impaired biceps recovery despite neurophysiological evidence of reinnervation. All had good shoulder and hand function at three months of age. Eight recovered a strong biceps after six months, but nine required a pectoralis minor to biceps transfer to augment elbow flexion and supination. One had a delayed but good recovery of the biceps after microsurgical reconstruction of the plexus. All had a clinical ‘pseudotumour’ in the biceps muscle, which was biopsied during pectoralis minor transfer in two patients and showed rupture and degeneration of muscle fibres with a fibro-fatty infiltrate, suggesting previous muscle trauma.

Direct muscle trauma is an uncommon but important cause of delayed or impaired biceps recovery after brachial plexus birth injuries. Surgery to reinnervate the biceps muscle will not work if substantial muscle damage is present when a suitable muscle transfer should be considered.

C5 nerve root palsy is a rare and potentially debilitating complication of cervical spine surgery. Currently, however, there are no guidelines to help surgeons to prevent or treat this complication.

We carried out a systematic review of the literature to identify the causes of this complication and options for its prevention and treatment. Searches of PubMed, Embase and Medline yielded 60 articles for inclusion, most of which addressed C5 palsy as a complication of surgery. Although many possible causes were given, most authors supported posterior migration of the spinal cord with tethering of the nerve root as being the most likely.

Early detection and prevention of a C5 nerve root palsy using neurophysiological monitoring and variations in surgical technique show promise by allowing surgeons to minimise or prevent the incidence of C5 palsy. Conservative treatment is the current treatment of choice; most patients make a full recovery within two years.

Cite this article: Bone Joint J 2014;96-B:950–5.

Ulnar neuropathy presents as a complication in 5% to 10% of total elbow replacements, but subsequent ulnar neurolysis is rarely performed. Little information is available on the surgical management of persistent ulnar neuropathy after elbow replacement. We describe our experience with the surgical management of this problem.

Of 1607 total elbow replacements performed at our institution between January 1969 and December 2004, eight patients (0.5%) had a further operation for persistent or progressive ulnar neuropathy. At a mean follow-up of 9.2 years (3.1 to 21.7) six were clinically improved and satisfied with their outcome, although, only four had complete recovery. When transposition was performed on a previously untransposed nerve the rate of recovery was 75%, but this was reduced to 25% if the nerve had been transposed at the time of the replacement.

A total of 38 relapsed congenital clubfeet (16 stiff, 22 partially correctable) underwent revision of soft-tissue surgery, with or without a bony procedure, and transfer of the tendon of tibialis anterior at a mean age of 4.8 years (2.0 to 10.1). The tendon was transferred to the third cuneiform in five cases, to the base of the third metatarsal in ten and to the base of the fourth in 23. The patients were reviewed at a mean follow-up of 24.8 years (10.8 to 35.6). A total of 11 feet were regarded as failures (one a tendon failure, five with a subtalar fusion due to over-correction, and five with a triple arthrodesis due to under-correction or relapse).

In the remaining feet the clinical outcome was excellent or good in 20 and fair or poor in seven. The mean Laaveg-Ponseti score was 81.6 of 100 points (52 to 92). Stiffness was mild in four feet and moderate or severe in 23.

Comparison between the post-operative and follow-up radiographs showed statistically significant variations of the talo-first metatarsal angle towards abduction. Variations of the talocalcaneal angles and of the overlap ratio were not significant.

Extensive surgery for relapsed clubfoot has a high rate of poor long-term results. The addition of transfer of the tendon of tibialis anterior can restore balance and may provide some improvement of forefoot adduction. However, it has a considerable complication rate, including failure of transfer, over-correction, and weakening of dorsiflexion. The procedure should be reserved for those limited cases in which muscle imbalance is a causative or contributing factor.

Total hip replacement (THR) after acetabular fracture presents unique challenges to the orthopaedic surgeon. The majority of patients can be treated with a standard THR, resulting in a very reasonable outcome. Technical challenges however include infection, residual pelvic deformity, acetabular bone loss with ununited fractures, osteonecrosis of bone fragments, retained metalwork, heterotopic ossification, dealing with the sciatic nerve, and the difficulties of obtaining long-term acetabular component fixation. Indications for an acute THR include young patients with both femoral head and acetabular involvement with severe comminution that cannot be reconstructed, and the elderly, with severe bony comminution. The outcomes of THR for established post-traumatic arthritis include excellent pain relief and functional improvements. The use of modern implants and alternative bearing surfaces should improve outcomes further.

Cite this article: Bone Joint J 2013;95-B, Supple A:11–16.

We studied 21 patients with a spontaneous palsy of the anterior interosseous nerve. There were 11 men and 10 women with a mean age at onset of 39 years (17 to 65).

Pain around the elbow or another region (forearm, shoulder, upper arm, systemic arthralgia) was present in 17 patients and typically lasted for two to three weeks. It had settled within six weeks in every case. In ten cases the palsy developed as the pain settled. A complete palsy of flexor pollicis longus and flexor digitorum profundus to the index finger was seen in 13 cases and an isolated palsy of flexor pollicis longus in five. All patients were treated without operation. The mean time to initial muscle contraction was nine months (2 to 18) in palsy of the flexor digitorum profundus to the index finger, and ten months (1 to 24) for a complete palsy of flexor pollicis longus. An improvement in muscle strength to British Medical Research Council grade 4 or better was seen in all 15 patients with a complete palsy of the flexor digitorum profundus and in 16 of 18 with a complete palsy of flexor pollicis longus.

There was no significant correlation between the duration of pain and either the time to initial muscle contraction or final muscle strength. Prolonged pain was not always associated with a poor outcome but the age of the patient when the palsy developed was strongly correlated. Recovery occurred within 12 months in patients under the age of 40 years who achieved a final British Medical Research Council grade of 4 or better. Surgical decompression does not appear to be indicated for young patients with this condition.

We describe 14 patients who underwent transfer of latissimus dorsi using a new technique through a single-incision. Their mean age was 61 years (47 to 76) and the mean follow-up was 32 months (19 to 42).

The mean Constant score improved from 46.5 to 74.6 points. The mean active flexion increased from 119° to 170°, mean abduction from 118° to 169° and mean external rotation from 19° to 33°. The Hornblower sign remained positive in three patients (23%) as did the external rotation lag sign also in three patients (23%). No patient had a positive drop-arm sign at follow-up. No significant difference was noted between the mean pre- and postoperative acromiohumeral distance as seen on radiographs. An increased grade of osteoarthritis was found in three patients (23%). Electromyographic analysis showed activity of the transferred muscle in all patients.