Aims

Spinal deformity surgery carries the risk of neurological injury. Neurophysiological monitoring allows early identification of intraoperative cord injury which enables early intervention resulting in a better prognosis. Although multimodal monitoring is the ideal, resource constraints make surgeon-directed intraoperative transcranial motor evoked potential (TcMEP) monitoring a useful compromise. Our experience using surgeon-directed TcMEP is presented in terms of viability, safety, and efficacy.

Upper limb amputations, ranging from transhumeral to partial hand, can be devastating for patients, their families, and society. Modern paradigm shifts have focused on reconstructive options after upper extremity limb loss, rather than considering the amputation an ablative procedure. Surgical advancements such as targeted muscle reinnervation and regenerative peripheral nerve interface, in combination with technological development of modern prosthetics, have expanded options for patients after amputation. In the near future, advances such as osseointegration, implantable myoelectric sensors, and implantable nerve cuffs may become more widely used and may expand the options for prosthetic integration, myoelectric signal detection, and restoration of sensation. This review summarizes the current advancements in surgical techniques and prosthetics for upper limb amputees.

Cite this article: Bone Joint J 2021;103-B(3):430–439.

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

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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.

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Magnetically controlled growing rod (MCGR) systems use non-invasive spinal lengthening for the surgical treatment of early-onset scoliosis (EOS). The primary aim of this study was to evaluate the performance of these devices in the prevention of progression of the deformity. A secondary aim was to record the rate of complications.

Introduction. The rate of total hip arthroplasty (THA) surgery continues to dramatically rise in the United States, with over 300,000 procedures performed in 2010. Although a relatively safe procedure, THA is not without complications. These complications include acetabular fracture, heterotopic ossification, implant failure, and nerve palsy to name a few. The rates of neurologic injury for a primary THA are reported as 0.7–3.5%. These rates increase to 7.6% for revision THA. The direct anterior total hip arthroplasty (DATHA) is gaining popularity amongst orthopedic surgeons. Many of these surgeons elect to use the Hana® table during this procedure for optimal positioning capability. Although intraoperative mobility and positioning of the hip joint during DATHA improves operative access, select positions of the limb put certain neurologic structures at risk. The most commonly reported neurologic injuries in this regard are to the sciatic and femoral nerves. To our knowledge, the use of neuromonitoring during DATHA, especially those using the Hana® table, has not been described in the literature. Methods. The patient was a 60-year-old male with long standing osteoarthritis of the right hip and prior left THA. Somatosensory evoked potential (SSEP) leads were placed bilaterally into the hand (ulnar nerve) as well as the popliteal fossae (posterior tibial nerve). Unilateral electromyography leads were placed into the vastus medialis obliquus, biceps femoris, gastrocnemius, tibialis anterior, and abductor hallucis of the operative limb (Fig. 1). Once the patient was sterilely draped, a direct anterior Smith-Peterson approach to the hip was used. Results. After the patient completed standard pre-operative protocol, neuromonitoring leads were placed as described above. There were no complications, neuromonitoring remained stable from baseline, and the patient tolerated the procedure well. Moreover, the senior author routinely uses a prophylactic cable around the calcar, particularly in patients with osteoporotic bone, as was the case with this patient. The patient's post-operative course has been without complications as well. Conclusion. There are a few studies that have examined the pressure changes around the femoral nerve during a DATHA and found that the nerve was at most danger with misplacement of a retractor near the anterior lip of the acetabulum. Furthermore, the popularity of DATHA and the Hana® table make neuromonitoring more amenable for use since the whole limb does not need to be sterilely prepped as with other approaches to the hip. The reported rates of neurologic injury during any THA along with those developed from passage of prophylactic cerclage cables and the goals of reducing surgical complications make this novel technique intriguing. It allows the surgeon yet another safe and effective tool to decrease the likelihood of neurologic injury during DATHA. For any figures or tables, please contact the authors directly

Aims

We present the results of correcting a double or triple curve adolescent idiopathic scoliosis using a convex segmental pedicle screw technique.

To examine the effect of lateral spine curvature on somatosensory evoked potentials (SSEP) in patients with adolescent idiopathic scoliosis (AIS) compared to normal controls. We hypothesise that patients with AIS will show increased latency in their SSEPs when bending into their curve suggesting that their spinal cord is more sensitive to this increased lateral curvature. Patients were recruited from the paediatric scoliosis clinic in a single centre. Inclusion criteria were: diagnosis of AIS, age 10–18 years, major thoracic curve measuring greater than 10 degrees on Cobb measurement, and undergoing nonoperative management. Exclusion criteria were: any detectable neurologic deficit, and previous surgery on the brain or spine. SSEP recordings were obtained via stimulation of the posterior tibial nerve with surface electrode and measurement of the cortical response over the scalp. All recordings were performed three times: with the patient in neutral standing and maximum right and left side bending. SSEP recordings show that when AIS subjects bend into their curve, latency slows by an average of 0.5ms. However there was a bimodal distribution with most subjects showing minimal change (3ms). This subset was statistically different from both a control group, and the larger AIS group. There appears to be a subset of patients with AIS who have subclinical spinal cord dysfunction demonstrated by abnormal SSEPs. This may place these patients at slightly higher risk of neurologic injury at the time of surgery

Clinical, radiological, and Scoliosis Research Society-22 questionnaire data were reviewed pre-operatively and two years post-operatively for patients with thoracolumbar/lumbar adolescent idiopathic scoliosis treated by posterior spinal fusion using a unilateral convex segmental pedicle screw technique. A total of 72 patients were included (67 female, 5 male; mean age at surgery 16.7 years (13 to 23)) and divided into groups: group 1 included 53 patients who underwent fusion between the vertebrae at the limit of the curve (proximal and distal end vertebrae); group 2 included 19 patients who underwent extension of the fusion distally beyond the caudal end vertebra.

A mean scoliosis correction of 80% (45% to 100%) was achieved. The mean post-operative lowest instrumented vertebra angle, apical vertebra translation and trunk shift were less than in previous studies. A total of five pre-operative radiological parameters differed significantly between the groups and correlated with the extension of the fusion distally: the size of the thoracolumbar/lumbar curve, the lowest instrumented vertebra angle, apical vertebra translation, the Cobb angle on lumbar convex bending and the size of the compensatory thoracic curve. Regression analysis allowed an equation incorporating these parameters to be developed which had a positive predictive value of 81% in determining whether the lowest instrumented vertebra should be at the caudal end vertebra or one or two levels more distal. There were no differences in the Scoliosis Research Society-22 outcome scores between the two groups (p = 0.17).

In conclusion, thoracolumbar/lumbar curves in patients with adolescent idiopathic scoliosis may be effectively treated by posterior spinal fusion using a unilateral segmental pedicle screw technique. Five radiological parameters correlate with the need for distal extension of the fusion, and an equation incorporating these parameters reliably informs selection of the lowest instrumented vertebra.

Cite this article: Bone Joint J 2014;96-B:1082–9.

Introduction. Somatosensory evoked potential (SSEP) monitoring allows for assessment of the spinal cord and susceptible structures during complex spinal surgery. It is well validated for the detection of potential neurological injury but little is known of surgeon's responses to an abnormal trace and its effect on neurological outcome. We aimed to investigate this in spinal deformity patients who are particularly vulnerable during their corrective surgery. Methods. Our institutional neurophysiology database was analysed between 1. st. October 2005 and 31. st. March 2010. Monitoring was performed by a team of trained neurophysiology technicians who were separate from the surgical team. A significant trace was defined as a 50% reduction in trace amplitude or a 10% increase in signal latency. Patients suffering a significant trace event were examined post-operatively by a Consultant Neurologist who was separate from the surgical team. Results. 2386 consecutive operations (F:1719, M:667 median age 16 yrs) were performed in the time period and 72 operations reported a significant trace event (‘red alert’). From these cases 47 (65%) had a clearly documented intervention by the surgeon and 7 patients overall suffered a lasting neurological deficit (0.3%). The most common timing events were during instrumentation (50%) and during correction/distraction (16%). Most common responses were optimisation of patient/monitoring set-up (23%) and adjustment of metalwork (22%). There were 18 wake-up tests performed. We found SSEP monitoring to have a sensitivity of 100%, specificity 97.4%, positive predictive value 14% and negative predictive value 100%. A Chi-square test (p=0.016) was significant suggesting intervention had a beneficial effect on neurological outcome. Conclusion. We would advocate the use of SSEP monitoring in all patients undergoing spinal deformity surgery. These patients tend to be young, neurologically intact pre-operatively and are particularly vulnerable to the large corrective forces their surgery requires

The December 2012 Children’s orthopaedics Roundup³⁶⁰ looks at: whether arthrodistraction is the answer to Perthes’ disease; deformity correction in tarsal coalitions; ultrasound used to predict pain in Osgood-Schlatter’s disease; acetabular tilt; hip replacement for juvenile arthritis sufferers; whether post-operative radiographs are needed for supracondylar fractures; intra-articular local anaesthetic following supracondylar fracture fixation; and limb deformity.

We undertook a retrospective analysis of 306 procedures on 233 patients, with a mean age of 12 years (1 to 21), in order to evaluate the use of somatosensory evoked potential (SSEP) monitoring for the early detection of nerve compromise during external fixation procedures for limb lengthening and correction of deformity. Significant SSEP changes were identified during 58 procedures (19%). In 32 instances (10.5%) the changes were transient, and resolved once the surgical cause had been removed. The remaining 26 (8.5%) were analysed in two groups, depending on whether or not corrective action had been performed in response to critical changes in the SSEP recordings. In 16 cases in which no corrective action was taken, 13 (81.2%, 4.2% overall) developed a post-operative neurological deficit, six of which were permanent and seven temporary, persisting for five to 18 months. In the ten procedures in which corrective action was taken, four patients (40%, 1.3% overall) had a temporary (one to eight months) post-operative neuropathy and six had no deficit. After appropriate intervention in response to SSEP changes, the incidence and severity of neurological deficits were significantly reduced, with no cases of permanent neuropathy. SSEP monitoring showed 100% sensitivity and 91% specificity for the detection of nerve injury during external fixation. It is an excellent diagnostic technique for identifying nerve lesions when they are still highly reversible.

Introduction. Evidence suggests that intra-operative spinal cord monitoring is sensitive and specific for detecting potential neurological injury. However, little is known about surgeons' responses to trace changes and the resultant neurological outcome. Objective. To examine the role of intra-operative somatosensory evoked potential (SSEP) monitoring in the prevention of neurological injury, specifically sensitivity and specificity, and whether the abnormalities were reversible. Methods. 2953 consecutive complex spine operations (male 36% female 64%, median age 25yrs) prospectively performed using spinal cord monitoring at a single institution (2005–2009). All traces and neurophysiological events were prospectively recorded by the neurophysiology technician. All patients with a significant neurophysiology event were examined clinically by a neurologist, separate from the spinal surgery team. Significant trace abnormality was defined as a decrease in signal amplitude of 50% or a 10% increase in latency. Timing of trace abnormality, surgeon's response and prospective neurological outcome were recorded. Sensitivity, specificity, positive/negative predictive value were calculated. A Chi-squared test was performed to assess the impact of intervention on neurological outcome (p < 0.05). Results. 2953 operations involving SSEP monitoring were performed and 106 recorded a significant trace abnormality. This most often occurred during instrumentation and the most common reaction was adjustment of metalwork. SSEP monitoring had a sensitivity of 100%, specificity 97.3%, PPV 24%, NPV 100%. There were 79 false positives and no false negatives in this series. Chi-squared test was not significant (p=0.18) suggesting that intervention might not affect neurological outcome in this cohort. Conclusions. Triggering events are uncommon and the development of a persistent neurological deficit is rare with an incidence of 0.85% in this series of 2953 operations. In the majority of cases detection of a monitoring abnormality prompts a corrective reaction by the surgeon. Of those with an abnormal trace 76% were neurologically normal at follow up

We reviewed 31 consecutive patients with Friedreich’s ataxia and scoliosis. There were 24 males and seven females with a mean age at presentation of 15.5 years (8.6 to 30.8) and a mean curve of 51° (13° to 140°). A total of 12 patients had thoracic curvatures, 11 had thoracolumbar and eight had double thoracic/lumbar. Two patients had long thoracolumbar collapsing scoliosis with pelvic obliquity and four had hyperkyphosis. Left-sided thoracic curves in nine patients (45%) and increased thoracic kyphosis differentiated these deformities from adolescent idiopathic scoliosis. There were 17 patients who underwent a posterior instrumented spinal fusion at mean age of 13.35 years, which achieved and maintained good correction of the deformity. Post-operative complications included one death due to cardiorespiratory failure, one revision to address nonunion and four patients with proximal junctional kyphosis who did not need extension of the fusion. There were no neurological complications and no wound infections. The rate of progression of the scoliosis in children kept under simple observation and those treated with bracing was less for lumbar curves during bracing and similar for thoracic curves. The scoliosis progressed in seven of nine children initially treated with a brace who later required surgery. Two patients presented after skeletal maturity with balanced curves not requiring correction. Three patients with severe deformities who would benefit from corrective surgery had significant cardiac co-morbidities.

Purpose. To compare the incidence and nature of ‘neurophysiological events’ identified, post hoc, by a consultant neurophysiologist with those identified intra-operatively by clinical physiologists, before and after intervention(s). Methods. The IOM wave-recordings, event-logs and reports of all spinal deformity cases conducted by a team of clinical physiologists from April to June 2009 (Group 1) were reviewed retrospectively by the same, experienced clinical neurophysiologist, (MG). Interventions were then agreed. The first was to alter the IOM report document to drop down menus. The second was to arrange a series of teaching sessions for the clinical physiologists on a variety of aspects of IOM. Finally during these teaching sessions recent cases were brought to review in an informal setting to discuss. Following implementation of the interventions a further review from April to June 2010 (Group 2) was carried out in the same manner. The clinical physiologists did not know the time periods over which the review would be taking place. Results. From April to June 2009 (Group 1) thirty two patients were studied and from April to June 2010 (Group 2) thirty four patients were studies. Group 1. Twenty seven of these had been monitored using ‘multimodal’ IOM consisting of cortical (CSEP) and spinal (SSEP) somatosensory evoked potentials and motor (MEP/CMAP) evoked potentials. Two patients were inappropriate for MEP recording and two were monitored using epidural SSEP recording. During 10 operations (31%) the surgeons were notified of an ‘intra-operative neurological event’ judged by the clinical neurophysiologist as potentially requiring a surgical response. When the results were audited, only 2 (6%) of these ‘events’ were considered by the consultant clinical neurophysiologist to represent ‘true positive’ intra-operative neurophysiological findings. Group 2. Twenty six of these had been monitored using ‘multimodal’ IOM consisting of cortical (CSEP) and spinal (SSEP) somatosensory evoked potentials and motor (MEP/CMAP) evoked potentials. Four patients were inappropriate for MEP recording and had a combination of SSEP and CSEP. The remainder had IOM with unimodal. No epidural IOM was used during this period. During 4 operations (12%) the surgeons were notified of an ‘intra-operative neurological event’ judged by the clinical neurophysiologist as potentially requiring a surgical response. Post-operative examination of all the patients in both groups revealed that no ‘false negative’ conclusions had been reached. Conclusion. In this series clinical physiologists were found to alert the surgeons 5 times more frequently than was likely to have been the case with an experienced consultant clinical neurophysiologist (31% and 6% respectively). However the increased reporting of intra-operative events did not result in any alteration of the ultimate surgical strategy in any operation although tactical changes were sometimes necessary during the operation in order to test the reversibility of the flagged event. The implementation of two simple interventions resulted in the clinical physiologists alerting the surgeons only 1/3 of that previously (12%) of cases. The log indicated that on all occasions appropriate surgical action had been taken with no residual neurological deficit. This study, owing to its size, cannot answer the key question of safety. Further work to estimate the statistical power required of such a study is being sought. In the interim proving a track record of successful cases provides evidence of efficacy. Ethics Approval: None. Interest Statement: None

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.

This review of the literature presents the current understanding of Scheuermann’s kyphosis and investigates the controversies concerning conservative and surgical treatment. There is considerable debate regarding the pathogenesis, natural history and treatment of this condition. A benign prognosis with settling of symptoms and stabilisation of the deformity at skeletal maturity is expected in most patients. Observation and programmes of exercise are appropriate for mild, flexible, non-progressive deformities. Bracing is indicated for a moderate deformity which spans several levels and retains flexibility in motivated patients who have significant remaining spinal growth.

The loss of some correction after the completion of bracing with recurrent anterior vertebral wedging has been reported in approximately one-third of patients. Surgical correction with instrumented spinal fusion is indicated for a severe kyphosis which carries a risk of progression beyond the end of growth causing cosmetic deformity, back pain and neurological complications. There is no consensus on the effectiveness of different techniques and types of instrumentation. Techniques include posterior-only and combined anteroposterior spinal fusion with or without posterior osteotomies across the apex of the deformity. Current instrumented techniques include hybrid and all-pedicle screw constructs.

The integrity of the spinal accessory nerve is fundamental to thoracoscapular function and essential for scapulohumeral rhythm. This nerve is vulnerable along its superficial course. This study assessed the delay in diagnosis and referral for management of damage to this nerve, clarified its anatomical course and function, and documented the results of repair. From examination of our records, 111 patients with lesions of the spinal accessory nerve were treated between 1984 and 2007. In 89 patients (80.2%) the damage was iatropathic. Recognition and referral were seldom made by the surgeon responsible for the injury, leading to a marked delay in instituting treatment. Most referrals were made for painful loss of shoulder function. The clinical diagnosis is straightforward. There is a characteristic downward and lateral displacement of the scapula, with narrowing of the inferior scapulohumeral angle and loss of function, with pain commonly present. In all, 80 nerves were explored and 65 were repaired. The course of the spinal accessory nerve in relation to the sternocleidomastoid muscle was constant, with branches from the cervical plexus rarely conveying motor fibres. Damage to the nerve was predominantly posterior to this muscle.

Despite the delay, the results of repair were surprising, with early relief of pain, implying a neuropathic source, which preceded generally good recovery of muscle function.

We evaluated the efficacy of anterior fusion alone compared with combined anterior and posterior fusion for the treatment of degenerative cervical kyphosis. Anterior fusion alone was undertaken in 15 patients (group A) and combined anterior and posterior fusion was carried out in a further 15 (group B). The degree and maintenance of the angle of correction, the incidence of graft subsidence, degeneration at adjacent levels and the rate of fusion were assessed radiologically and clinically and the rate of complications recorded. The mean angle of correction in group B was significantly higher than in group A (p = 0.0009). The mean visual analogue scale and the neck disability index in group B was better than in group A (p = 0.043, 0.0006). The mean operation time and the blood loss in B were greater than in group A (p < 0.0001, 0.037). Pseudarthrosis, subsidence of the cage, and problems related to the hardware were more prevalent in group A than in group B (p = 0.034, 0.025, 0.013).

Although the combined procedure resulted in a longer operating time and greater blood loss than with anterior fusion alone, our results suggest that for the treatment of degenerative cervical kyphosis the combined approach leads to better maintenance of sagittal alignment, a higher rate of fusion, a lower incidence of complications and a better clinical outcome.