Adolescent idiopathic scoliosis (AIS), defined by an age at presentation of 11 to 18 years, has a prevalence of 0.47% and accounts for approximately 90% of all cases of idiopathic scoliosis. Despite decades of research, the exact aetiology of AIS remains unknown. It is becoming evident that it is the result of a complex interplay of genetic, internal, and environmental factors. It has been hypothesized that genetic variants act as the initial trigger that allow epigenetic factors to propagate AIS, which could also explain the wide phenotypic variation in the presentation of the disorder. A better understanding of the underlying aetiological mechanisms could help to establish the diagnosis earlier and allow a more accurate prediction of deformity progression. This, in turn, would prompt imaging and therapeutic intervention at the appropriate time, thereby achieving the best clinical outcome for this group of patients.

Cite this article: Bone Joint J 2022;104-B(8):915–921.

Aims. The aim of this study was to assess the accuracy of pedicle screw placement, as well as intraoperative factors, radiation exposure, and complication rates in adult patients with degenerative disorders of the thoracic and lumbar spines who have undergone robotic-navigated spinal surgery using a contemporary system. Methods. The authors reviewed the prospectively collected data on 196 adult patients who had pedicle screws implanted with robot-navigated assistance (RNA) using the Mazor X Stealth system between June 2019 and March 2022. Pedicle screws were implanted by one experienced spinal surgeon after completion of a learning period. The accuracy of pedicle screw placement was determined using intraoperative 3D fluoroscopy. Results. A total of 1,123 pedicle screws were implanted: 1,001 screws (89%) were placed robotically, 63 (6%) were converted from robotic placement to a freehand technique, and 59 (5%) were planned to be implanted freehand. Of the robotically placed screws, 942 screws (94%) were determined to be Gertzbein and Robbins grade A with median deviation of 0.8 mm (interquartile range 0.4 to 1.6). Skive events were noted with 20 pedicle screws (1.8%). No adverse clinical sequelae were noted in the 90-day follow-up. The mean fluoroscopic exposure per screw was 4.9 seconds (SD 3.8). Conclusion. RNA is highly accurate and reliable, with a low rate of abandonment once mastered. No adverse clinical sequelae occurred after implanting a large series of pedicle screws using the latest generation of RNA. Understanding of patient-specific anatomical features and the real-time intraoperative identification of risk factors for suboptimal screw placement have the potential to improve accuracy further. Cite this article: Bone Joint J 2023;105-B(5):543–550

We validated the North American Spine Society (NASS) outcome-assessment instrument for the lumbar spine in a computerised touch-screen format and assessed patients’ acceptance, taking into account previous computer experience, age and gender. Fifty consecutive patients with symptomatic and radiologically-proven degenerative disease of the lumbar spine completed both the hard copy (paper) and the computerised versions of the NASS questionnaire. Statistical analysis showed high agreement between the paper and the touch-screen computer format for both subscales (intraclass correlation coefficient 0.94, 95% confidence interval (0.90 to 0.97)) independent of computer experience, age and gender. In total, 55% of patients stated that the computer format was easier to use and 66% preferred it to the paper version (p < 0.0001 among subjects expressing a preference). Our data indicate that the touch-screen format is comparable to the paper form. It may improve follow-up in clinical practice and research by meeting patients’ preferences and minimising administrative work

Aims. The aim of this study was to investigate the impact of the level of upper instrumented vertebra (UIV) in frail patients undergoing surgery for adult spine deformity (ASD). Methods. Patients with adult spinal deformity who had undergone T9-to-pelvis fusion were stratified using the ASD-Modified Frailty Index into not frail, frail, and severely frail categories. ASD was defined as at least one of: scoliosis ≥ 20°, sagittal vertical axis (SVA) ≥ 5 cm, or pelvic tilt ≥ 25°. Means comparisons tests were used to assess differences between both groups. Logistic regression analyses were used to analyze associations between frailty categories, UIV, and outcomes. Results. A total of 477 patients were included (mean age 60.3 years (SD 14.9), mean BMI 27.5 kg/m. 2. (SD 5.8), mean Charlson Comorbidity Index (CCI) 1.67 (SD 1.66)). Overall, 74% of patients were female (n = 353), and 49.6% of patients were not frail (237), 35.4% frail (n = 169), and 15% severely frail (n = 71). At baseline, differences in age, BMI, CCI, and deformity were significant (all p = 0.001). Overall, 15.5% of patients (n = 74) had experienced mechanical complications by two years (8.1% not frail (n = 36), 15.1% frail (n = 26), and 16.3% severely frail (n = 12); p = 0.013). Reoperations also differed between groups (20.2% (n = 48) vs 23.3% (n = 39) vs 32.6% (n = 23); p = 0.011). Controlling for osteoporosis, baseline deformity, and degree of correction (by sagittal age-adjusted score (SAAS) matching), frail and severely frail patients were more likely to experience mechanical complications if they had heart failure (odds ratio (OR) 6.6 (95% CI 1.6 to 26.7); p = 0.008), depression (OR 5.1 (95% CI 1.1 to 25.7); p = 0.048), or cancer (OR 1.5 (95% CI 1.1 to 1.4); p = 0.004). Frail and severely frail patients experienced higher rates of mechanical complication than ‘not frail’ patients at two years (19% (n = 45) vs 11.9% (n = 29); p = 0.003). When controlling for baseline deformity and degree of correction in severely frail and frail patients, severely frail patients were less likely to experience clinically relevant proximal junctional kyphosis or failure or mechanical complications by two years, if they had a more proximal UIV. Conclusion. Frail patients are at risk of a poor outcome after surgery for adult spinal deformity due to their comorbidities. Although a definitively prescriptive upper instrumented vertebra remains elusive, these patients appear to be at greater risk for a poor outcome if the upper instrumented vertebra is sited more distally. Cite this article: Bone Joint J 2024;106-B(11):1342–1347

Aims. Patients may present with concurrent symptomatic osteoarthritis (OA) of the hip and degenerative disorders of the lumbar spine, with surgical treatment being indicated for both. Whether arthroplasty of the hip or spinal surgery should be performed first remains uncertain. Materials and Methods. Clinical scenarios were devised for a survey asking the preferred order of surgery and the rationale for this decision for five fictional patients with both OA of the hip and degenerative lumbar disorders. These were symptomatic OA of the hip and: 1) lumbar spinal stenosis with neurological claudication; 2) lumbar degenerative spondylolisthesis with leg pain; 3) lumbar disc herniation with leg weakness; 4) lumbar scoliosis with back pain; and 5) thoracolumbar disc herniation with myelopathy. This survey was sent to 110 members of The Hip Society and 101 members of the Scoliosis Research Society. The choices of the surgeons were compared among scenarios and between surgical specialties using the chi-squared test. The free-text comments were analyzed using text-mining. Results. Responses were received from 51 hip surgeons (46%) and 37 spine surgeons (37%). The percentages of hip surgeons recommending ‘hip first’ differed significantly among scenarios: 59% for scenario 1; 73% for scenario 2; 47% for scenario 3; 47% for scenario 4; and 10% for scenario 5 (p < 0.001). The percentages of spine surgeons recommending ‘hip first’ were 49% for scenario 1; 70% for scenario 2; 19% for scenario 3; 78% for scenario 4; and 0% for scenario 5. There were significant differences between the groups for scenarios 3 (more hip surgeons recommended ‘hip first’; p = 0.012) and 4 (more hip surgeons recommended ‘spine first’; p = 0.006). Conclusion. In patients with coexistent OA of the hip and degenerative disorders of the spine, the question of ‘hip or spinal surgery first’ elicits relatively consistent answers in some clinical scenarios, but remains controversial in others, even for experienced surgeons. The nature of neurological symptoms can influence surgeons’ decision-making. Cite this article: Bone Joint J 2019;101-B(6 Supple B):37–44

Aims. The aim of this study was to determine the differences in spinal imaging characteristics between subjects with or without lumbar developmental spinal stenosis (DSS) in a population-based cohort. Methods. This was a radiological analysis of 2,387 participants who underwent L1-S1 MRI. Means and ranges were calculated for age, sex, BMI, and MRI measurements. Anteroposterior (AP) vertebral canal diameters were used to differentiate those with DSS from controls. Other imaging parameters included vertebral body dimensions, spinal canal dimensions, disc degeneration scores, and facet joint orientation. Mann-Whitney U and chi-squared tests were conducted to search for measurement differences between those with DSS and controls. In order to identify possible associations between DSS and MRI parameters, those who were statistically significant in the univariate binary logistic regression were included in a multivariate stepwise logistic regression after adjusting for demographics. Odds ratios (ORs) and 95% confidence intervals (CIs) were reported where appropriate. Results. Axial AP vertebral canal diameter (p < 0.001), interpedicular distance (p < 0.001), AP dural sac diameter (p < 0.001), lamina angle (p < 0.001), and sagittal mid-vertebral body height (p < 0.001) were significantly different between those identified as having DSS and controls. Narrower interpedicular distance (OR 0.745 (95% CI 0.618 to 0.900); p = 0.002) and AP dural sac diameter (OR 0.506 (95% CI 0.400 to 0.641); p < 0.001) were associated with DSS. Lamina angle (OR 1.127 (95% CI 1.045 to 1.214); p = 0.002) and right facet joint angulation (OR 0.022 (95% CI 0.002 to 0.247); p = 0.002) were also associated with DSS. No association was observed between disc parameters and DSS. Conclusion. From this large-scale cohort, the canal size is found to be independent of body stature. Other than spinal canal dimensions, abnormal orientations of lamina angle and facet joint angulation may also be a result of developmental variations, leading to increased likelihood of DSS. Other skeletal parameters are spared. There was no relationship between DSS and soft tissue changes of the spinal column, which suggests that DSS is a unique result of bony maldevelopment. These findings require validation in other ethnicities and populations. Level of Evidence: I (diagnostic study). Cite this article: Bone Joint J 2021;103-B(4):725–733

Aims. Chronic low back pain due to degenerative disc disease is sometimes treated with fusion. We compared the outcome of three different fusion techniques in the Swedish Spine Register: noninstrumented posterolateral fusion (PLF), instrumented posterolateral fusion (IPLF), and interbody fusion (IBF). Patients and Methods. A total of 2874 patients who were operated on at one or two lumbar levels were followed for a mean of 9.2 years (3.6 to 19.1) for any additional lumbar spine surgery. Patient-reported outcome data were available preoperatively (n = 2874) and at one year (n = 2274), two years (n = 1958), and a mean of 6.9 years (n = 1518) postoperatively and consisted of global assessment and visual analogue scales of leg and back pain, Oswestry Disability Index, EuroQol five-dimensional index, 36-Item Short-Form Health Survey, and satisfaction with treatment. Statistical analyses were performed with competing-risks proportional hazards regression or analysis of covariance, adjusted for baseline variables. Results. The number of patients with additional surgery were 32/183 (17%) in the PLF group, 229/1256 (18%) in the IPLF group, and 439/1435 (31%) in the IBF group. With the PLF group as a reference, the hazard ratio for additional lumbar surgery was 1.16 (95% confidence interval (CI) 0.78 to 1.72) for the IPLF group and 2.13 (95% CI 1.45 to 3.12) for the IBF group. All patient-reported outcomes improved after surgery (p < 0.001) but were without statistically significant differences between the groups at the one-, two- and 6.9-year follow-ups (all p ≥ 0.12). Conclusion. The addition of interbody fusion to posterolateral fusion was associated with a higher risk for additional surgery and showed no advantages in patient-reported outcome. Cite this article: Bone Joint J 2019;101-B:1526–1533

Aims. While previously underappreciated, factors related to the spine contribute substantially to the risk of dislocation following total hip arthroplasty (THA). These factors must be taken into consideration during preoperative planning for revision THA due to recurrent instability. We developed a protocol to assess the functional position of the spine, the significance of these findings, and how to address different pathologies at the time of revision THA. Patients and Methods. Prospectively collected data on 111 patients undergoing revision THA for recurrent instability from January 2014 to January 2017 at two institutions were included (protocol group) and matched 1:1 to 111 revisions specifically performed for instability not using this protocol (control group). Mean follow-up was 2.8 years. Protocol patients underwent standardized preoperative imaging including supine and standing anteroposterior (AP) pelvis and lateral radiographs. Each case was scored according to the Hip-Spine Classification in Revision THA. Results. Survival free of dislocation at two years was 97% in the protocol group (three dislocations, all within three months of surgery) versus 84% in the control group (18 patients). Furthermore, 77% of the inappropriately positioned acetabular components would have been unrecognized by supine AP pelvis imaging alone. Conclusion. Using the Hip-Spine Classification System in revision THA, we demonstrated a significant decrease in the risk of recurrent instability compared with a control group. Without the use of this algorithm, 77% of inappropriately positioned acetabular components would have been unrecognized and incorrect treatment may have been instituted. Cite this article: Bone Joint J 2019;101-B:817–823

Aims. The surgical treatment of tuberculosis (TB) of the spine consists of debridement and reconstruction of the anterior column. Loss of correction is the most significant challenge. Our aim was to report the outcome of single-stage posterior surgery using bone allografts in the management of this condition. Patients and Methods. The study involved 24 patients with thoracolumbar TB who underwent single-stage posterior spinal surgery with a cortical bone allograft for anterior column reconstruction and posterior instrumentation between 2008 and 2015. A unilateral approach was used for 21 patients with active TB, and a bilateral approach with decompression and closing-opening wedge osteotomy was used for three patients with healed TB. Results. A median of 1.25 vertebrae were removed (interquartile range (IQR) 1 to 1.75) and the median number of levels that were instrumented was five (IQR 3 to 6). The median operating time was 280 minutes (IQR 230 to 315) and the median blood loss was 700 ml (IQR 350 to 900). The median postoperative kyphosis was 8.5° (IQR 0° to 15°) with a mean correction of the kyphosis of 71.6%. Good neurological recovery occurred, with only two patients (8%) requiring assistance to walk at a mean follow-up of 24 months (9 to 50), at which time there was a mean improvement in disability, as assessed by the Oswestry Disability Index, of 83% (90% to 72%). Conclusion. The posterior-only approach using cortical allografts for anterior column reconstruction achieved good clinical and radiological outcomes. Differentiation should be made between flexible (active) and rigid (healed) TB spine. Cite this article: Bone Joint J 2018;100-B:1208–13

The dismal outcome of tuberculosis of the spine in the pre-antibiotic era has improved significantly because of the use of potent antitubercular drugs, modern diagnostic aids and advances in surgical management. MRI allows the diagnosis of a tuberculous lesion, with a sensitivity of 100% and specificity of 88%, well before deformity develops. Neurological deficit and deformity are the worst complications of spinal tuberculosis. Patients treated conservatively show an increase in deformity of about 15°. In children, a kyphosis continues to increase with growth even after the lesion has healed. Tuberculosis of the spine is a medical disease which is not primarily treated surgically, but operation is required to prevent and treat the complications. Panvertebral lesions, therapeutically refractory disease, severe kyphosis, a developing neurological deficit, lack of improvement or deterioration are indications for surgery. Patients who present with a kyphosis of 60° or more, or one which is likely to progress, require anterior decompression, posterior shortening, posterior instrumented stabilisation and anterior and posterior bone grafting in the active stage of the disease. Late-onset paraplegia is best prevented rather than treated. The awareness and suspicion of an atypical presentation of spinal tuberculosis should be high in order to obtain a good outcome. Therapeutically refractory cases of tuberculosis of the spine are increasing in association with the presence of HIV and multidrug-resistant tuberculosis

Aims. The aim of the study was to compare measures of the quality of life (QOL) after resection of a chordoma of the mobile spine with the national averages in the United States and to assess which factors influenced the QOL, symptoms of anxiety and depression, and coping with pain post-operatively in these patients. Patients and Methods. A total of 48 consecutive patients who underwent resection of a primary or recurrent chordoma of the mobile spine between 2000 and 2015 were included. A total of 34 patients completed a survey at least 12 months post-operatively. The primary outcome was the EuroQol-5 Dimensions (EQ-5D-3L) questionnaire. Secondary outcomes were the Patient-Reported Outcome Measurement Information System (PROMIS) anxiety, depression and pain interference questionnaires. Data which were recorded included the indication for surgery, the region of the tumour, the number of levels resected, the status of the surgical margins, re-operations, complications, neurological deficit, length of stay in hospital and rate of re-admission. Results. The median EQ-5D-3L score was 0.71 (interquartile range (IQR) 0.44 to 0.79) which is worse than the national average in the United States of 0.85 (p < 0.001). Anxiety (median: 55 (IQR 49 to 61), p = 0.031) and pain (median: 61 (IQR 56 to 68), p < 0.001) were also worse than the national average in the United States (50), while depression was not (median: 52 (IQR 38 to 57), p = 0.513). Patients who underwent a primary resection had better QOL and less anxiety, depression and pain compared with those who underwent resection for recurrent or residual disease. The one- and five-year probabilities were 0.96 and 0.74 for survival, 0.07 and 0.25 for tumour recurrence, and 0.02 and 0.16 for developing distant metastasis. A total of 25 local complications occurred in 20 patients (42%), and there were 50 systemic and other complications in 25 patients (52%) within 90 days. Conclusion. These patient reported outcomes and oncological and surgical outcomes can be used when counselling patients and to aid decision-making when planning surgery. Cite this article: Bone Joint J 2017;99-B:979–86

We report five children who presented at the mean age of 1.5 years (1.1 to 1.9) with a progressive thoracolumbar kyphosis associated with segmental instability and subluxation of the spine at the level above an anteriorly-wedged hypoplastic vertebra at L1 or L2. The spinal deformity appeared to be developmental and not congenital in origin. The anterior wedging of the vertebra may have been secondary to localised segmental instability and subsequent kyphotic deformity. We suggest the term ‘infantile developmental thoracolumbar kyphosis with segmental subluxation of the spine’ to differentiate this type of deformity from congenital displacement of the spine in which the congenital vertebral anomaly does not resolve. Infantile developmental kyphosis with segmental subluxation of the spine, if progressive, may carry the risk of neurological compromise. In all of our patients the kyphotic deformity progressed over a period of three months and all were treated by localised posterior spinal fusion. At a mean follow-up of 6.6 years (5.0 to 9.0), gradual correction of the kyphosis was seen on serial radiographs as well as reconstitution of the hypoplastic wedged vertebra to normality. Exploration of the arthrodesis was necessary at nine months in one patient who developed a pseudarthrosis

Acute angulation at the thoracolumbar junction with segmental subluxation of the spine occurring at the level above an anteriorly hypoplastic vertebra in otherwise normal children is a rare condition described as infantile developmental thoracolumbar kyphosis. Three patient series with total of 18 children have been reported in the literature. We report five children who presented with thoracolumbar kyphosis and discuss the treatment algorithm. We reviewed the medical records and spinal imaging at initial clinical presentation and at minimum two-year follow-up. The mean age at presentation was eight months (two to 12). All five children had L2 anterior vertebral body hypoplasia. The kyphosis improved spontaneously in three children kept under monitoring. In contrast, the deformity was progressive in two patients who were treated with bracing. The kyphosis and segmental subluxation corrected at latest follow-up (mean age 52 months; 48 to 60) in all patients with near complete reconstitution of the anomalous vertebra. The deformity and radiological imaging on a young child can cause anxiety to both parents and treating physicians. Diagnostic workup and treatment algorithm in the management of infantile developmental thoracolumbar kyphosis is proposed. Observation is indicated for non-progressive kyphosis and bracing if there is evidence of kyphosis and segmental subluxation deterioration beyond walking age. Surgical stabilisation of the spine can be reserved for severe progressive deformities unresponsive to conservative treatment. . Cite this article: Bone Joint J 2015;97-B:982–7

There have been very few reports in the literature of gout and pseudogout of the spine. We describe six patients who presented with acute sciatica attributable to spinal stenosis with cyst formation in the facet joints. Cytopathological studies confirmed the diagnosis of crystal arthropathy in each case. Specific formation of a synovial cyst was identified pre-operatively by MRI in five patients. In the sixth, the diagnosis was made incidentally during decompressive surgery. Surgical decompression alone was undertaken in four patients. In one with an associated degenerative spondylolisthesis, an additional intertransverse fusion was performed. Another patient had previously undergone a spinal fusion adjacent to the involved spinal segment, and spinal stabilisation was undertaken as well as a decompression. In addition to standard histological examination material was sent for examination under polarised light which revealed deposition of urate or calcium pyrophosphate dihydrate crystals in all cases. It is not possible to diagnose gout and pseudogout of the spine by standard examination of a fixed specimen. However, examining dry specimens under polarised light suggests that crystal arthropathy is a significant aetiological factor in the development of symptomatic spinal stenosis associated with cyst formation in a facet joint

1. Previous studies of the movements of the lumbar spine are criticised in the light of new observations from radiograph tracings. It is shown that, contrary to recent teaching, the lumbar spine is a very mobile part of the vertebral column. 2. The movement of the lumbar spine is analysed. It is shown that the lower vertebrae have the most movement, and that the range gradually becomes less in the upper lumbar spine. 3. This movement may be roughly correlated with the incidence of spurs arising from the anterior margin of the vertebral bodies. 4. These spurs are shown to arise in the anterior longitudinal ligament; they are probably caused by intermittent pressure from the intervertebral disc lying behind the ligament

Aims. During revision procedures for aseptic reasons, there remains a suspicion that failure may have been the result of an undetected subclinical infection. However, there is little evidence available in the literature about unexpected positive results in presumed aseptic revision spine surgery. The aims of our study were to estimate the prevalence of unexpected positive culture using sonication and to evaluate clinical characteristics of these patients. Patients and Methods. All patients who underwent a revision surgery after instrumented spinal surgery at our institution between July 2014 and August 2016 with spinal implants submitted for sonication were retrospectively analyzed. Only revisions presumed as aseptic are included in the study. During the study period, 204 spinal revisions were performed for diagnoses other than infection. In 38 cases, sonication cultures were not obtained, leaving a study cohort of 166 cases. The mean age of the cohort was 61.5 years (. sd. 20.4) and there were 104 female patients. Results. Sonication cultures were positive in 75 cases (45.2%). Hardware failure was the most common indication for revision surgery and revealed a positive sonication culture in 26/75 cases (35%) followed by adjacent segment disease (ASD) in 23/75 cases (30%). Cutibacterium acnes and Staphylococcus epidermidis were the most commonly isolated microorganisms, observed in 45% and 31% of cases, respectively. C. acnes was isolated in 65.2% of cases when the indication for revision surgery was ASD. Conclusion. Infection must always be considered as a possibility in the setting of spinal revision surgery, especially in the case of hardware failure, regardless of the lack of clinical signs. Sonication should be routinely used to isolate microorganisms adherent to implants. Cite this article: Bone Joint J 2019;101-B:621–624

The main form of treatment of a chordoma of the mobile spine is total en bloc spondylectomy (TES), but the clinical results are not satisfactory. Stand-alone carbon ion radiotherapy (CIRT) for bone and soft-tissue sarcomas has recently been reported to have a high rate of local control with a low rate of local recurrence. . We report two patients who underwent TES after CIRT for treating a chordoma in the lumbar spine with good medium-term outcomes. At operation, there remained histological evidence of viable tumour cells in both cases. After the combination use of TES following CIRT, neither patient showed signs of recurrence at the follow-up examination. These two cases suggest that CIRT should be combined with total spondylectomy in the treatment of chordoma of the mobile spine. Cite this article: Bone Joint J 2013;95-B:1392–5

A 30-year-old man presented with pain and limitation of movement of the right hip. The symptoms had failed to respond to conservative treatment. Radiographs and CT scans revealed evidence of impingement between the femoral head-neck junction and an abnormally large anterior inferior iliac spine. Resection of the hypertrophic anterior inferior iliac spine was performed which produced full painless restoration of function of the hip. Hypertrophy of the anterior inferior iliac spine as a cause of femoro-acetabular impingement has not previously been described

Dysplasia epiphysealis hemimelica of the left proximal femur was diagnosed in an eight-month-old girl. At the age of 18 months, radiographs of the hip and MRI showed overgrowth and loss of containment of the femoral head. She underwent resection of the superior portion of the head and neck of the femur at the age of 2.5 years. Six months later further radiographs and an MR scan show that the mass has increased in size and that hip containment has been lost. Further plain radiographs have shown that the left knee, ankle and spine were involved. To the authors’ knowledge, this is the first report of dysplasia epiphysealis hemimelica involving both the lower limb and the spine. A review of the literature is presented

The effective capture of outcome measures in the healthcare setting can be traced back to Florence Nightingale’s investigation of the in-patient mortality of soldiers wounded in the Crimean war in the 1850s. Only relatively recently has the formalised collection of outcomes data into Registries been recognised as valuable in itself. With the advent of surgeon league tables and a move towards value based health care, individuals are being driven to collect, store and interpret data. Following the success of the National Joint Registry, the British Association of Spine Surgeons instituted the British Spine Registry. Since its launch in 2012, over 650 users representing the whole surgical team have registered and during this time, more than 27 000 patients have been entered onto the database. There has been significant publicity regarding the collection of outcome measures after surgery, including patient-reported scores. Over 12 000 forms have been directly entered by patients themselves, with many more entered by the surgical teams. Questions abound: who should have access to the data produced by the Registry and how should they use it? How should the results be reported and in what forum?. Cite this article: Bone Joint J 2015;97-B:871–4

A series of experiments showing how posture affects the lumbar spine is reviewed. Postures which flatten (that is, flex) the lumbar spine are compared with those that preserve the lumbar lordosis. Our review shows that flexed postures have several advantages: flexion improves the transport of metabolites in the intervertebral discs, reduces the stresses on the apophyseal joints and on the posterior half of the annulus fibrosus, and gives the spine a high compressive strength. Flexion also has disadvantages: it increases the stress on the anterior annulus and increases the hydrostatic pressure in the nucleus pulposus at low load levels. The disadvantages are not of much significance and we conclude that it is mechanically and nutritionally advantageous to flatten the lumbar spine when sitting and when lifting heavy weights

Aims

Although lumbosacral transitional vertebrae (LSTV) are well-documented, few large-scale studies have investigated thoracolumbar transitional vertebrae (TLTV) and spinal numerical variants. This study sought to establish the prevalence of numerical variants and to evaluate their relationship with clinical problems.

The aim of this study was first, to determine whether CT scans undertaken to identify serious injury to the viscera were of use in detecting clinically unrecognised fractures of the thoracolumbar vertebrae, and second, to identify patients at risk of ‘missed injury’. . We retrospectively analysed CT scans of the chest and abdomen performed for blunt injury to the torso in 303 patients. These proved to be positive for thoracic and intra-abdominal injuries in only 2% and 1.3% of cases, respectively. However, 51 (16.8%) showed a fracture of the thoracolumbar vertebrae and these constituted our subset for study. There were eight women and 43 men with mean age of 45.2 years (15 to 94). There were 29 (57%) stable and 22 (43%) unstable fractures. Only 17 fractures (33.3%) had been anticipated after clinical examination. Of the 22 unstable fractures, 11 (50%) were anticipated. Thus, within the whole group of 303 patients, an unstable spinal injury was missed in 11 patients (3.6%); no harm resulted as they were all protected until the spine had been cleared. A subset analysis revealed that patients with a high Injury Severity Score, a low Glasgow Coma Scale and haemodynamic instability were most likely to have a significant fracture in the absence of positive clinical findings. This is the group at greatest risk. Clinical examination alone cannot detect significant fractures of the thoracolumbar spine. It should be combined with CT imaging to reduce the risk of missed injury

1. Posterior fusion of the spine in scoliosis cannot be relied upon to maintain correction of the curve or to prevent progression of a vicious resistant curve. It can, however, hold to some extent the correction of a mobile curve and the compensation of a fixed curve. 2. Despite generally poor results as assessed radiographically, the clinical improvement is often gratifying. Most patients claim to be greatly improved: the spine feels stronger, there is less fatigue, and balance is better controlled. Moreover, visible deformity may be improved markedly even though the anatomical correction as observed radiographically is slight (Figs. l0 and 11). 3. It is believed that the true cause of relapse is that the bone formed from sliver grafts remains immature for a long time. Even when incorporated with the immature bone of the child's spine or the mature bone of the adult spine, it remains soft and resilient. When subjected to the stresses and strains of weight bearing and gravity, and then to the unnatural forces which initiated or perpetuated the scoliosis, this immature bone undergoes remodelling to Wolff's Law—like the neck of the femur after slipping of the upper femoral epiphysis. The forces that alter the grafted bone are not only lateral forces but also—perhaps more important—rotational forces. There seems to be a definite link between the degree of rotation and the amount of relapse, correction being maintained best when rotation is least

1. Nine hundred and fourteen cases of tuberculosis of the spine are analysed and the late results ascertained three or more years after discharge from hospital. 2. The relative frequency with which the various segments of the spine are involved has been found. Cervical disease was present in 3·5 per cent of cases, thoracic in 43·l per cent, lumbar in 32·9 per cent, thoraco-lumbar in 16· 7 per cent and lumbo-sacral in 3·8 per cent. 3. The mortality rate was 16·7 per cent. In patients with multiple lesions 25·5 per cent died, compared with 12·3 per cent in the group without complications. When chronic secondarily infected abscesses and sinuses were present the mortality rate was 19·1 per cent, and of patients with paraplegia 24·8 per cent died. 4. In the late results the working capacity of 390 patients was ascertained. It was full in 86 per cent, partial in 5·8 per cent and nil in 8·2 per cent. 5. An attempt has been made to determine the site of the primary bone focus from the radiograph. Early "epiphysial" changes were present in 33 per cent ; the central focus beginning in the spongy tissue of a vertebral body was present in 11·6 per cent; subperiosteal lesions were present in 2·1 per cent; and infection of the neural arch was present in only 0·5 per cent. In 52·8 per cent, however, widespread destruction had taken place when the patient first came under observation. 6. The ill effect of complications upon the prognosis is stressed—especially in the cases of multiple foci of active tuberculosis, secondarily infected abscesses and sinuses, and paraplegia. Paraplegia occurred in 31·2 per cent of the cases of thoracic disease. 7. An attempt has been made to determine the frequency with which tuberculosis of the spine heals by spontaneous bony fusion of the affected vertebral bodies. It was found in 27·3 per cent of the cases in the present series. 8. Reasons for further treatment after the initial discharge of the patient are examined

Injury to the spinal cord and kyphosis are the two most feared complications of tuberculosis of the spine. Since tuberculosis affects principally the vertebral bodies, anterior decompression is usually recommended. Concomitant posterior instrumentation is indicated to neutralise gross instability from panvertebral disease, to protect the anterior bone graft, to prevent graft-related complications after anterior decompression in long-segment disease and to correct a kyphosis. Two-stage surgery is usually performed in these cases. We present 38 consecutive patients with tuberculosis of the spine for whom anterior decompression, posterior instrumentation, with or without correction of the kyphus, and anterior and posterior fusion was performed in a single stage through an anterolateral extrapleural approach. Their mean age was 20.4 years (2.0 to 57.0). The indications for surgery were panvertebral disease, neurological deficit and severe kyphosis. The patients were operated on in the left lateral position using a ‘T’-shaped incision sited at the apex of kyphosis or lesion. Three ribs were removed in 34 patients and two in four and anterior decompression of the spinal cord was carried out. The posterior vertebral column was shortened to correct the kyphus, if necessary, and was stabilised by a Hartshill rectangle and sublaminar wires. Anterior and posterior bone grafting was performed. The mean number of vertebral bodies affected was 3.24 (2.0 to 9.0). The mean pre-operative kyphosis in patients operated on for correction of the kyphus was 49.08° (30° to 72°) and there was a mean correction of 25° (6° to 42°). All except one patient with a neural deficit recovered complete motor and sensory function. The mean intra-operative blood loss was 1175 ml (800 to 2600), and the mean duration of surgery 3.5 hours (2.7 to 5.0). Wound healing was uneventful in 33 of 38 patients. The mean follow-up was 33 months (11 to 74). None of the patients required intensive care. The extrapleural anterolateral approach provides simultaneous exposure of the anterior and posterior aspects of the spine, thereby allowing decompression of the spinal cord, posterior stabilisation and anterior and posterior bone grafting. This approach has much less morbidity than the two-stage approaches which have been previously described

Percutaneous placement of pedicle screws is a well-established technique, however, no studies have compared percutaneous and open placement of screws in the thoracic spine. The aim of this cadaveric study was to compare the accuracy and safety of these techniques at the thoracic spinal level. A total of 288 screws were inserted in 16 (eight cadavers, 144 screws in percutaneous and eight cadavers, 144 screws in open). Pedicle perforations and fractures were documented subsequent to wide laminectomy followed by skeletalisation of the vertebrae. The perforations were classified as grade 0: no perforation, grade 1: < 2 mm perforation, grade 2: 2 mm to 4 mm perforation and grade 3: > 4 mm perforation. In the percutaneous group, the perforation rate was 11.1% with 15 (10.4%) grade 1 and one (0.7%) grade 2 perforations. In the open group, the perforation rate was 8.3% (12 screws) and all were grade 1. This difference was not significant (p = 0.45). There were 19 (13.2%) pedicle fractures in the percutaneous group and 21 (14.6%) in the open group (p = 0.73). In summary, the safety of percutaneous fluoroscopy-guided pedicle screw placement in the thoracic spine between T4 and T12 is similar to that of the conventional open technique. Cite this article: Bone Joint J 2015;97-B:1555–61

We investigated the spines of 15 patients who had significant leg-length inequality as a result of femoral shaft fractures sustained after skeletal maturity but below the age of 21 years. The patients were examined at least 10 years after fracture. The spines were studied clinically and radiographically before and after correction of leg-length inequality with a shoe-raise. Lateral spinal flexion was measured from radiographs. The lumbar scoliosis associated with the leg-length inequality was compensatory: after equalisation of leg-length the overall curve and the axial rotation were corrected completely. There was also an equal range of lateral flexion to either side after correction. Minor malalignments of the whole spine remained despite correction of the compensatory scoliosis, and within the lumbar spine correction of the scoliosis had not occurred equally at all levels. No patients complained of significant discomfort and neither structural abnormalities nor degenerative changes were seen on the radiographs

1. The long-term results of 740 European patients suffering from spinal tuberculosis and treated without and with specific anti-tuberculous drugs have been surveyed. 2. The results of treatment by conservative methods and by conventional surgical methods have been compared in the two periods. The attainment of spinal stability as judged by serial examination of radiographs was the main criterion in assessing healing. 3. Although the results of conventional treatment have improved since the advent of chemotherapy, the credit is mainly due to the influence of more frequently and more expertly applied operations. 4. With chemotherapy the well tried medical and surgical procedures produce stable spines in three-quarters of cases. With early operation on the lesion the results are better and more quickly obtained. Of eighty spines on which focal surgery was performed during the past twelve years before the lesions had become extensive, seventy-seven (9·62 per cent) healed by bone. The average duration of hospitalisation after such operation was four and a half months. No patient has had to be readmitted. 5. The difficulties and possible dangers of these methods must be emphasised. The operations are difficult and dangerous when the lesions have been allowed to get out of hand and become unduly extensive. They are contra-indicated in cases where there is very marked deformity. 6. Training in special techniques of operation is necessary. Duplicated drainage of the hemithorax after thoracotomy is essential, and skilled after-care is important if good results are to be obtained

A modified transthoracic approach to the thoracic vertebral column is described. In this method, the parietal pleura is detached from the chest wall and retracted with the visceral pleura and its contents. A direct approach to the vertebral bodies is thus achieved without transgression of the intrapleural space. The technique can be extended to include exposure of the thoracolumbar spinal column, utilising a thoracoabdominal approach with extrapleural and extraperitoneal dissection. Management of the costophrenic detachment is thus simplified. This approach has significant advantages for orthopaedic, vascular and neurosurgical procedures

1. The literature on hyperextension injuries of the spine is briefly reviewed. 2. Such injuries in the cervical spine can be subdivided into five groups based on the pathological anatomy, based on the experience of fifty-one patients in the Spinal Injuries Centre for Victoria over the past five years. 3. Extension injuries of the thoraco-lumbar spine are discussed. They are rare and have a poor prognosis. 4. The importance of treatment based on sound clinical and pathological knowledge is emphasised, particularly in order that stable and unstable lesions may be recognised early and managed correctly

We present a prospective study of patients with tuberculosis of the dorsal, dorsolumbar and lumbar spine after combined anterior (radical debridement and anterior fusion) and posterior (instrumentation and fusion) surgery. The object was to study the progress of interbody union, the extent of correction of the kyphosis and its maintenance with early mobilisation, and the incidence of graft and implant-related problems. The American Spinal Injury Association (ASIA) score was used to assess the neurological status. The mean preoperative vertebral loss was highest (0.96) in the dorsal spine. The maximum correction of the kyphosis in the dorsolumbar spine was 17.8°. Loss of correction was maximal in the lumbosacral spine at 13.7°. All patients had firm anterior fusion at a mean of five months. The incidence of infection was 3.9% and of graft-related problems 6.5%. We conclude that adjuvant posterior stabilisation allows early mobilisation and rehabilitation. Graft-related problems were fewer and the progression and maintenance of correction of the kyphosis were better than with anterior surgery alone. There is no additional risk relating to the use of an implant either posteriorly or anteriorly even when large quantities of pus are present

Between 1955 and 1989 we treated 24 patients (17 women and seven men) with giant-cell tumours of the spine at the Mayo Clinic. Their mean age was 30 years and the mean follow-up time was 12.4 years. Pain was the presenting symptom in all and half had a neurological deficit. The cervical, thoracic, and lumbar spines were equally involved. The tumours recurred in five of the 14 patients treated by one-stage surgery and in five of the ten treated by two-stage surgery. Seven patients received adjuvant radiotherapy, one for the primary lesion and six for recurrent lesions. Surgical management was by curettage or en bloc excision depending on the location and the extent of the tumour. Because of the risk of sarcomatous transformation, radiation therapy should be reserved for patients with incomplete excision or for those with local recurrence

We studied 21 former top-class competitive javelin throwers to investigate radiological and clinical symptoms in the lumbar spine many years after the end of their athletic careers. The athletes underwent clinical and radiological examinations at an average of 20 years after retiring from athletics. The Hannover questionnaire was used to evaluate functional restrictions in daily living. Degenerative changes in the lumbar spine were more marked towards the caudal aspect of the spine. Ten athletes also had spondylolisthesis, but with little progression (< 15%) throughout the observation period. Athletes both with and without radiologically demonstrated spondylolisthesis, complained of no more back problems than the normal population (93% for athletes v 86% for controls). Slight progression followed their retirement from athletics

We carried out an MRI study of the lumbar spine in 15 patients with achondroplasia to evaluate the degree of stenosis of the canal. They were divided into asymptomatic and symptomatic groups. We measured the sagittal canal diameter, the sagittal cord diameter, the interpedicular distance at the mid-pedicle level and the cross-sectional area of the canal and spinal cord at mid-body and mid-disc levels. The MRI findings showed that in achondroplasia there was a significant difference between the groups in the cross-sectional area of the body canal at the upper lumbar levels. Patients with a narrower canal are more likely to develop symptoms of spinal stenosis than others

1. A proven case of typhoid spine in a patient with sickle cell trait (AS) is recorded. It responded well to conservative treatment with chloramphenicol. 2. The literature on typhoid spine is briefly reviewed and the relationship between salmonella osteomyelitis and sickle cell disease is discussed

Continuous technical improvement in spinal surgical procedures, with the aim of enhancing patient outcomes, can be assisted by the deployment of advanced technologies including navigation, intraoperative CT imaging, and surgical robots. The latest generation of robotic surgical systems allows the simultaneous application of a range of digital features that provide the surgeon with an improved view of the surgical field, often through a narrow portal.

There is emerging evidence that procedure-related complications and intraoperative blood loss can be reduced if the new technologies are used by appropriately trained surgeons. Acceptance of the role of surgical robots has increased in recent years among a number of surgical specialities including general surgery, neurosurgery, and orthopaedic surgeons performing major joint arthroplasty. However, ethical challenges have emerged with the rollout of these innovations, such as ensuring surgeon competence in the use of surgical robotics and avoiding financial conflicts of interest. Therefore, it is essential that trainees aspiring to become spinal surgeons as well as established spinal specialists should develop the necessary skills to use robotic technology safely and effectively and understand the ethical framework within which the technology is introduced.

Traditional and more recently developed platforms exist to aid skill acquisition and surgical training which are described.

The aim of this narrative review is to describe the role of surgical robotics in spinal surgery, describe measures of proficiency, and present the range of training platforms that institutions can use to ensure they employ confident spine surgeons adequately prepared for the era of robotic spinal surgery.

Cite this article: Bone Joint J 2020;102-B(5):568–572.

Primary malignant tumours should be resected with wide margins. This may be difficult to apply to lesions of the spine. We undertook total vertebrectomy on seven patients, four males and three females with a mean age at operation of 26.5 years (6.3 to 45.8). The mean follow-up was 52.3 months. Histological examination revealed a Ewing’s sarcoma in two patients and osteosarcoma, leiomyosarcoma, spindle-cell sarcoma, chondrosarcoma and malignant schwannoma in one each. In five patients, histological examination showed that a wide resection had been achieved. At follow-up there was no infection and a permanent neurological deficit was only seen in those patients in whom the surgical procedure had required resection of nerve roots. Despite the high demands placed on the surgeon and anaesthetist and the length of postoperative care we consider total vertebrectomy to be an appropriate procedure for the operative treatment of primary malignant lesions of the spine

1. Vascular anatomical studies of the spine are described and the possibility of spread of infection from pelvis to spine through the paravertebral venous plexus is discussed. 2. Though a venous route does exist, our studies do not support the supposition that infection is likely to spread by this route; nor is there any clear clinical, pathological or anatomical evidence that such spread occurs. 3. Nineteen cases of pyogenic osteomyelitis of the spine are recorded, six of which followed urinary infections. The condition is compared with osteomyelitis as it occurs in the other bones of adults

The factors during and after operation which influence the development of a solid and stable posterior spinal fusion have been evaluated in 406 patients with scoliosis. The patients were managed in three different ways and all pseudarthroses were accurately detected by exploring the spines six months after the attempted fusion. The incidence of pseudarthroses was significantly lowered from 25 per cent in Group I to 3.8 per cent in Group III by the application of Harrington instrumentation and the use of large amounts of autogenous iliac bone grafts in addition to an interfacetal fusion. Early mobilisation 7 to 10 days after operation and a return to normal activities in a well-moulded underarm plaster jacket did not have a detrimental effect on the development of the fusion or the early maintenance of correction. Those spines with supplementary bone grafts stabilised more rapidly and had better maintenance of correction with only minimal loss after removal of all external support at 10 months

One hundred and fifty patients in Hong Kong with a diagnosis of tuberculosis of the thoracic, thoracolumbar or lumbar spine were allocated a random to the "Hong Kong" radical resection of the lesion and the insertion of autologous bone grafts (Rad. series) or to debridement of the spinal focus without bone grafting (Deb. series). All patients received daily chemotherapy with para-aminosalicylic acid (PAS) plus isoniazid for 18 months, with streptomycin for the first three months. After exclusions, the main analyses of this report concern 119 patients (58 Rad., 61 Deb.) followed up for 10 years. During the first five years the allocated regimen was modified because of the spinal lesion in 14 patients, but there were no further modifications between five and 10 years. No patient developed a sinus or clinically evident abscess or a neurological abnormality between five and 10 years. Bony fusion occurred earlier and in a higher proportion of patients in the Rad, series but at five and 10 years there was vary little difference between the series. Over the period of 10 years there was a mean increase in vertebral loss of 0.05 of a vertebral body in the Rad. series and 0.23 in the Deb. series. In both series most of this loss occurred in the first 18 months, with very little subsequent change in the next eight and a half years. Over the 10 years there was a mean reduction in the angle of kyphosis in the Rad. series of 1.4 degrees for patients with thoracic and thoracolumbar lesions and 0.5 degrees for those with lumbar lesions. By contrast, in the Deb. series there were mean increases in the angle of 9.8 degrees and 7.6 degrees respectively. In both series most of the changes had occurred early, and persisted subsequently. At 10 years 57 of 58 Rad. and all 61 Deb. patients had a favourable status, 50 (86 per cent) and 54 (89 per cent) respectively on the allocated regimen without modification

We performed a biomechanical study on human cadaver spines to determine the effect of three different interbody cage designs, with and without posterior instrumentation, on the three-dimensional flexibility of the spine. Six lumbar functional spinal units for each cage type were subjected to multidirectional flexibility testing in four different configurations: intact, with interbody cages from a posterior approach, with additional posterior instrumentation, and with cross-bracing. The tests involved the application of flexion and extension, bilateral axial rotation and bilateral lateral bending pure moments. The relative movements between the vertebrae were recorded by an optoelectronic camera system. We found no significant difference in the stabilising potential of the three cage designs. The cages used alone significantly decreased the intervertebral movement in flexion and lateral bending, but no stabilisation was achieved in either extension or axial rotation. For all types of cage, the greatest stabilisation in flexion and extension and lateral bending was achieved by the addition of posterior transpedicular instrumentation. The addition of cross-bracing to the posterior instrumentation had a stabilising effect on axial rotation. The bone density of the adjacent vertebral bodies was a significant factor for stabilisation in flexion and extension and in lateral bending

The skeleton is the most common site to be affected by metastatic cancer. The place of surgical treatment and of different techniques of reconstruction has not been clearly defined. We have studied the rate of survival of 94 patients and the results of the surgical treatment of 91 metastases of the limbs and pelvis, and 18 of the spine. Variables included the different primary tumours, the metastatic load at the time of operation, the surgical margin, and the different techniques of reconstruction. The survival rate was 0.54 at one year and 0.27 at three years. Absence of visceral metastases and of a pathological fracture, a time interval of more than three years between the diagnosis of cancer and that of the first skeletal metastasis, thyroid carcinoma, prostate carcinoma, renal-cell carcinoma, breast cancer, and plasmacytoma were positive variables with regard to survival. The metastatic load of the skeleton and the surgical margin were not of significant influence. In tumours of the limbs and pelvis, the local failure rate was 0% after biological reconstruction (10), 3.6% after cemented or uncemented osteosynthesis (28) and 1.8% after prosthetic replacement (53). The local failure rate after stabilisation of the spine (18) was 16.6%. There was local recurrence in seven patients (6.4%), and in four of these the primary tumour was a renal-cell carcinoma. The local recurrence rate was 0% after extralesional (24) and 8.2% after intralesional resection (85). Improvements in the oncological management of patients with primary and metastatic disease have resulted in an increased survival rate. In order to avoid additional surgery, it is essential to consider the expected time of survival of the reconstruction and, in bony metastases with a potentially poor response to radiotherapy, the surgical margin

Giant-cell tumour of the synovium is known to affect the fingers or toes of adults. It has seldom been described in the spine and rarely in the thoracic vertebrae or in a child. The lesions of giant-cell tumour of the synovium have a classical radiological appearance, but require a high index of suspicion for correct recognition. Unlike giant-cell tumour of the synovium at other well-known sites, spinal lesions lack the characteristic papillary architecture, thereby raising other diagnostic possibilities. We describe a giant-cell tumour of the synovium of the left facet joint of a thoracic vertebra in a nine-year-old girl. The tumour was treated successfully by surgical excision

Assessment of bony union after anterior fusion of the lumbar spine has previously relied on the skilled interpretation of plain radiograph. A biplanar radiographic technique was used to measure small movements between vertebrae and to give a quantitative measure of bony union in 11 patients who had undergone interbody fusion with autogenous bone chips at one level in the lumbar spine. The investigation gave three types of results: bony union, where the fused level showed marked restriction of movement relative to the rest of the lumbar spine; paradoxical movement, where the fused joint showed marked reverse movement (when the patient flexed, the fused level of the lumbar spine extended) which was thought to be due to an anterior bony bar which caused an altered pattern of movement; and non-union, where the level of fusion showed no restriction of movement. The intervertebral joint above the level of fusion was shown to move more than the other joints in the lumbar spine. The study showed that bony union is possible with the use of autogenous cancellous bone chips, and that biplanar radiographic technique can determine the extent of union

Two hundred and eighty-three patients with tuberculosis of the thoracic and/or lumbar spine have been followed for 10 years from the start of treatment. All patients received PAS plus isoniazid daily for 18 months, either with streptomycin for the first three months (SPH) or no streptomycin (PH), by random allocation. There was also a second random allocation for all patients: in Masan to inpatient rest in bed (IP) for six months followed by outpatient treatment or to ambulatory outpatient treatment from the start (OP), and in Pusan to outpatient treatment with a plaster-of-Paris jacket (J) for nine months or to ambulatory treatment without any support (No J). A favourable status was achieved on their allocated regimen by 88% of patients at 10 years. Some of the remaining patients also attained a favourable status after additional chemotherapy and/or operation, and if these are included the proportion achieving such a status increases to 96%. There were five patients whose deaths were attributed to their spinal disease. A sinus or clinically evident abscess was present on at least one occasion in the 10-year period in 42% of the patients. Residual sinuses persisted at 10 years in two patients, at death at seven years in a third and at default in the seventh year in a fourth. Thirty-five patients had paraparesis at some time during the 10-year period, including two who died with paraplegia before five years. Complete resolution occurred in 26 patients (in six after additional chemotherapy and/or surgery). At 10 years two patients had severe paraplegia and one a moderate paraparesis.(ABSTRACT TRUNCATED AT 250 WORDS)

We undertook a retrospective study investigating the accuracy and safety of percutaneous pedicle screws placed under fluoroscopic guidance in the lumbosacral junction and lumbar spine. The CT scans of patients were chosen from two centres: European patients from University Medical Center Hamburg-Eppendorf, Germany, and Asian patients from the University of Malaya, Malaysia. Screw perforations were classified into grades 0, 1, 2 and 3. A total of 880 percutaneous pedicle screws from 203 patients were analysed: 614 screws from 144 European patients and 266 screws from 59 Asian patients. The mean age of the patients was 58.8 years (16 to 91) and there were 103 men and 100 women. The total rate of perforation was 9.9% (87 screws) with 7.4% grade 1, 2.0% grade 2 and 0.5% grade 3 perforations. The rate of perforation in Europeans was 10.4% and in Asians was 8.6%, with no significant difference between the two (p = 0.42). The rate of perforation was the highest in S1 (19.4%) followed by L5 (14.9%). The accuracy and safety of percutaneous pedicle screw placement are comparable to those cited in the literature for the open method of pedicle screw placement. Greater caution must be taken during the insertion of L5 and S1 percutaneous pedicle screws owing to their more angulated pedicles, the anatomical variations in their vertebral bodies and the morphology of the spinal canal at this location. Cite this article: Bone Joint J 2015; 97-B:1111–17

In two centres in Korea 350 patients with a diagnosis of tuberculosis of the thoracic and/or lumbar spine were allocated at random: in Masan to in-patient rest in bed (IP) for six months followed by out-patient treatment or to ambulatory out-patient treatment (OP) from the start; in Pusan to out-patient treatment with a plaster-of-Paris jacket (J) for nine months or to ambulatory treatment without any support (No J). All patients recieved chemotherapy with PAS with isoniazid for eighteen months, either supplemented with streptomycin for the first three months (SPH) or without this supplement (PH), by random allocation. The main analysis of this report concerns 299 patients (eighty-three IP, eighty-three OP, sixty-three J, seventy No J; 143 SPH, 156 PH). Pre-treatment factors were similar in both centres except that the patients in Pusan had, on average, less extensive lesions although in a greater proportion the disease was radiographically active. One patient (J/SPH) died with active spinal disease and three (all No J/SPH) with paraplegia. A fifth patient (IP/PH) who died from cardio respiratory failure also had pulmonary tuberculosis. Twenty-three patients required operation and/or additional chemotherapy for the spinal lesion. A sinus or clinically evident abscess was either present initially or developed during treatment in 41 per cent of patients. Residual lesions persisted in ten patients (four IP, two OP, one J, three No J; six SPH, four PH) at five years. Thirty-two patients had paraparesis on admission or developing later. Complete resolution occurred in twenty on the allocated regimen and in eight after operation or additional chemotherapy or both. Of the remaining four atients, all of whom had operation and additional chemotherapy, three died and one still had paraparesis at five years. Of 295 patients assessed at five years 89 per cent had a favourable status. The proportions of the patients responding favourably were similar in the IP (91 per cent) and OP (89 per cent) series, in the J (90 per cent) and No J (84 per cent) series and in the SPH (86 per cent) and PH (92 per cent) series

1. A case of chordoma of the thoracic spine is described. 2. Certain features of this case–notably the absence of vertebral destruction–are contrasted with those of cases previously described