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

We describe a surgical approach to the upper thoracic spine which allows an adequate exposure of the vertebral bodies from T1 to T3. The approach causes little functional disturbance and is especially useful in older patients with spinal tumours causing spinal cord compression

We report three cases of thoracic spine translocation without neurological deficit. In each case bilateral pedicular fractures, demonstrated by computed tomography, produced 'floating arches' which account for the sparing of the cord. If computed tomography demonstrates adequate canal dimensions, these patients may be treated conservatively, but the treatment of choice at specialist spinal centres is operative stabilisation

In spinal tuberculosis MRI can clearly demonstrate combinations of anterior and posterior lesions as well as pedicular involvement. We propose a classification system, using information provided by MRI, to help to plan the appropriate surgical treatment for patients with thoracic spinal tuberculosis. We describe a series of 47 patients, divided into four groups, based on the surgical protocol used in the management. Group A consisted of patients with anterior lesions which were stable with no kyphotic deformity, and were treated with anterior debridement and strut grafting. Group B comprised patients with global lesions, kyphosis and instability who were treated with posterior instrumentation using a closed-loop rectangle with sublaminar wires, and by anterior strut grafting. Group C were patients with anterior or global lesions as in the previous groups, but who were at a high risk for transthoracic surgery because of medical and possible anaesthetic complications. These patients had a global decompression of the cord posteriorly, the anterior portion of the cord being approached through a transpedicular route. Posterior instrumentation was with a closed-loop rectangle held by sublaminar wires. Group D comprised patients with isolated posterior lesions which required posterior decompression only.

An understanding of the extent of vertebral destruction can be obtained from MRI studies. This information can be used to plan appropriate surgery.

The spinal manifestations of neurofibromatosis include cervicothoracic kyphosis, in which scalloping of the vertebral body and erosion of the pedicles may render conventional techniques of fixation impossible. We describe a case of cervicothoracic kyphosis managed operatively with a vascularised fibular graft anteriorly across the apex of the kyphus, followed by a long posterior construct using translaminar screws, which allow segmental fixation in vertebral bodies where placement of the pedicle screws was impracticable.

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.

1. A left-sided, paravertebral, hour-glass tumour causing destruction of the neural arches of the third and fourth thoracic vertebrae with evidence of spinal cord compression, is described. The tumour presented the typical histological appearance of a chondroblastoma.

2. The intraspinal part of the tumour was excised and the mediastinal part curetted. Post-operative radiotherapy was given. The patient was symptomless two years after operation.

3. No example of Codman's tumour with similar features and in such a situation has been described before in the literature. Pathological, clinical and radiological aspects of chondroblastomata are briefly discussed and some remarks concerning their treatment are added.

Aims. We aimed to retrospectively assess the accuracy and safety of CT navigated pedicle screws and to compare accuracy in the cervical and thoracic spine (C2-T8) with (COMB) and without (POST) prior anterior surgery (anterior cervical discectomy or corpectomy and fusion with ventral plating: ACDF/ACCF). Patients and Methods. A total of 592 pedicle screws, which were used in 107 consecutively operated patients (210 COMB, 382 POST), were analysed. The accuracy of positioning was determined according to the classification of Gertzbein and Robbins on post-operative CT scans. Results. High accuracy was achieved in 524 screws (88.5%), 192 (87.7%) in the cervical spine and 332 (89%) in the thoracic spine, respectively. The results in the two surgical groups were compared and a logistic regression mixed model was performed to analyse the risk of low accuracy. Significantly lower accuracy was found in the COMB group with 82.9% versus 91.6% in the POST group (p = 0.036). There were no neurological complications, but two vertebral artery lesions were recorded. Three patients underwent revision surgery for malpositioning of a screw. Although the risk of malpositioning of a screw after primary anterior surgery was estimated to be 2.4-times higher than with posterior surgery alone, the overall rates of complication and revision were low. Conclusion. We therefore conclude that CT navigated pedicle screws can be positioned safely although greater caution must be taken in patients who have previously undergone anterior surgery. Cite this article: Bone Joint J 2017;99-B:1373–80

Aims. To evaluate the perioperative complications associated with total en bloc spondylectomy (TES) in patients with spinal tumours, based on the extent and level of tumour resection. Methods. In total, 307 patients who underwent TES in a single centre were reviewed retrospectively. There were 164 male and 143 female patients with a mean age at the time of surgery of 52.9 years (SD 13.3). A total of 225 patients were operated on for spinal metastases, 34 for a malignant primary tumour, 41 for an aggressive benign tumour, and seven with a primary of unknown origin. The main lesion was located in the thoracic spine in 213, and in the lumbar spine in 94 patients. There were 97 patients who underwent TES for more than two consecutive vertebrae. Results. Major and minor perioperative complications were observed in 122 (39.7%) and 84 (27.4%) patients respectively. The breakdown of complications was as follows: bleeding more than 2,000 ml in 60 (19.5%) patients, hardware failure in 82 (26.7%), neurological in 46 (15.0%), surgical site infection in 23 (7.5%), wound dehiscence in 16 (5.2%), cerebrospinal fluid leakage in 45 (14.7%), respiratory in 52 (16.9%), cardiovascular in 11 (3.6%), digestive in 19 (6.2%)/ The mortality within two months of surgery was four (1.3%). The total number of complications per operation were 1.01 (SD 1.0) in the single vertebral resection group and 1.56 (SD 1.2) in the group with more than two vertebral resections. Cardiovascular and respiratory complications, along with hardware failure were statistically higher in the group who had more than two vertebrae resected. Also, in this group the amount of bleeding in patients with a lumbar lesion or respiratory complication in patients with a thoracic lesion, were statistically higher. Multivariate analysis showed that using a combined anterior and posterior approach, when more than two vertebral resections were significant independent factors. Conclusion. The characteristics of perioperative complications after TES were different depending on the extent and level of the tumour resection. In addition to preoperative clinical and pathological factors, it is therefore important to consider these factors in patients who undergo en bloc resection for spinal tumours. Cite this article: Bone Joint J 2021;103-B(5):976–983

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

Aims. The aim of this study was to determine the influence of pelvic parameters on the tendency of patients with adolescent idiopathic scoliosis (AIS) to develop flatback deformity (thoracic hypokyphosis and lumbar hypolordosis) and its effect on quality-of-life outcomes. Patients and Methods. This was a radiological study of 265 patients recruited for Boston bracing between December 2008 and December 2013. Posteroanterior and lateral radiographs were obtained before, immediately after, and two-years after completion of bracing. Measurements of coronal and sagittal Cobb angles, coronal balance, sagittal vertical axis, and pelvic parameters were made. The refined 22-item Scoliosis Research Society (SRS-22r) questionnaire was recorded. Association between independent factors and outcomes of postbracing ≥ 6° kyphotic changes in the thoracic spine and ≥ 6° lordotic changes in the lumbar spine were tested using likelihood ratio chi-squared test and univariable logistic regression. Multivariable logistic regression models were then generated for both outcomes with odds ratios (ORs), and with SRS-22r scores. Results. Reduced T5-12 kyphosis (mean -4.3° (. sd. 8.2); p < 0.001), maximum thoracic kyphosis (mean -4.3° (. sd. 9.3); p < 0.001), and lumbar lordosis (mean -5.6° (. sd. 12.0); p < 0.001) were observed after bracing treatment. Increasing prebrace maximum kyphosis (OR 1.133) and lumbar lordosis (OR 0.92) was associated with postbracing hypokyphotic change. Prebrace sagittal vertical axis (OR 0.975), prebrace sacral slope (OR 1.127), prebrace pelvic tilt (OR 0.940), and change in maximum thoracic kyphosis (OR 0.878) were predictors for lumbar hypolordotic changes. There were no relationships between coronal deformity, thoracic kyphosis, or lumbar lordosis with SRS-22r scores. Conclusion. Brace treatment leads to flatback deformity with thoracic hypokyphosis and lumbar hypolordosis. Changes in the thoracic spine are associated with similar changes in the lumbar spine. Increased sacral slope, reduced pelvic tilt, and pelvic incidence are associated with reduced lordosis in the lumbar spine after bracing. Nevertheless, these sagittal parameter changes do not appear to be associated with worse quality of life. Cite this article: Bone Joint J 2019;101-B:1370–1378

Aims. To compare the rates of sagittal and coronal correction for all-pedicle screw instrumentation and hybrid instrumentation using sublaminar bands in the treatment of thoracic adolescent idiopathic scoliosis (AIS). Methods. We retrospectively reviewed the medical records of 124 patients who had undergone surgery in two centres for the correction of Lenke 1 or 2 AIS. Radiological evaluation was carried out preoperatively, in the early postoperative phase, and at two-year follow-up. Parameters measured included coronal Cobb angles and thoracic kyphosis. Postoperative alignment was compared after matching the cohorts by preoperative coronal Cobb angle, thoracic kyphosis, lumbar lordosis, and pelvic incidence. Results. A total of 179 patients were available for analysis. After matching, 124 patients remained (62 in each cohort). Restoration of thoracic kyphosis was significantly better in the sublaminar band group than in the pedicle screw group (from 23.7° to 27.5° to 34.0° versus 23.9° to 18.7° to 21.5°; all p < 0.001). When the preoperative thoracic kyphosis was less than 20°, sublaminar bands achieved a normal postoperative thoracic kyphosis, whereas pedicle screws did not. In the coronal plane, pedicle screws resulted in a significantly better correction than sublaminar bands at final follow-up (73.0% versus 59.7%; p < 0.001). Conclusion. This is the first study to compare sublaminar bands and pedicle screws for the correction of a thoracic AIS. We have shown that pedicle screws give a good coronal correction which is maintained at two-year follow-up. Conversely, sublaminar bands restore the thoracic kyphosis better while pedicle screws are associated with a flattening of the thoracic spine. In patients with preoperative hypokyphosis, sublaminar bands should be used to restore a proper sagittal profile. Cite this article: Bone Joint J 2020;102-B(3):376–382

We have reviewed our experience in managing 11 patients who sustained an indirect sternal fracture in combination with an upper thoracic spinal injury between 2003 and 2006. These fractures have previously been described as ‘associated’ fractures, but since the upper thorax is an anatomical entity composed of the upper thoracic spine, ribs and sternum joined together, we feel that the term ‘fractures of the upper transthoracic cage’ is a better description. These injuries are a challenge because they are unusual and easily overlooked. They require a systematic clinical and radiological examination to identify both lesions. This high-energy trauma gives severe devastating concomitant injuries and CT with contrast and reconstruction is essential after resuscitation to confirm the presence of all the lesions. The injury level occurs principally at T4–T5 and at the manubriosternal joint. These unstable fractures need early posterior stabilisation and fusion or, if treated conservatively, a very close follow-up

Segmental vessel ligation during anterior spinal surgery has been associated with paraplegia. However, the incidence and risk factors for this devastating complication are debated. We reviewed 346 consecutive paediatric and adolescent patients ranging in age from three to 18 years who underwent surgery for anterior spinal deformity through a thoracic or thoracoabdominal approach, during which 2651 segmental vessels were ligated. There were 173 patients with idiopathic scoliosis, 80 with congenital scoliosis or kyphosis, 43 with neuromuscular and 31 with syndromic scoliosis, 12 with a scoliosis associated with intraspinal abnormalities, and seven with a kyphosis. There was only one neurological complication, which occurred in a patient with a 127° congenital thoracic scoliosis due to a unilateral unsegmented bar with contralateral hemivertebrae at the same level associated with a thoracic diastematomyelia and tethered cord. This patient was operated upon early in the series, when intra-operative spinal cord monitoring was not available. Intra-operative spinal cord monitoring with the use of somatosensory evoked potentials alone or with motor evoked potentials was performed in 331 patients. This showed no evidence of signal change after ligation of the segmental vessels. In our experience, unilateral segmental vessel ligation carries no risk of neurological damage to the spinal cord unless performed in patients with complex congenital spinal deformities occurring primarily in the thoracic spine and associated with intraspinal anomalies at the same level, where the vascular supply to the cord may be abnormal

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).

Aims

The aim of this study was to investigate the incidence and characteristics of instrumentation failure (IF) after total en bloc spondylectomy (TES), and to analyze risk factors for IF.

Radiographic examination of a giraffe-necked woman shows that there is no true elongation of the cervical spine. The apparent lengthening of the neck is due to incorporation of part of the thoracic spine and thorax in the neck

A case is described of bilateral traumatic chylothorax after complete dislocation of the thoracic spine. An explanation is advanced for the delayed, sudden onset of symptoms due to the chylothorax in this and other cases

Injury to the spinal cord without radiological abnormality often occurs in the skeletally immature cervical and thoracic spine. We describe four adult patients with this diagnosis involving the cervical spine with resultant quadriparesis. The relevant literature is reviewed. The implications for initial management of the injury, the role of MRI and the need for a high index of suspicion are highlighted

The anterior exposure of the upper thoracic spine using standard methods is often difficult and limited. We report our experience using a technique described by Sundaresan et al. (1984) in which the medial portion of one clavicle and part of the manubrium sterni are excised. In 10 cases we found this to be a useful and safe procedure

Aims

Closed suction subfascial drainage is widely used after instrumented posterior spinal fusion in patients with a spinal deformity. The aim of this study was to determine the effect of this wound drainage on the outcomes in patients with adolescent idiopathic scoliosis (AIS). This was a further analysis of a randomized, multicentre clinical trial reporting on patients after posterior spinal fusion using segmental pedicle screw instrumentation. In this study the incidence of deep surgical site infection (SSI) and chronic postoperative pain at two years’ follow-up are reported.

We describe a method for approaching the lower cervical and upper thoracic spine, the brachial plexus and related vessels. The method involves the elevation of the medial corner of the manubrium, the sternoclavicular joint, and the medial half of the clavicle on a pedicle of the sternomastoid muscle. We have used this exposure in 17 cases with few complications and good results. Its successful performance requires high standards of anaesthesia, surgical technique and postoperative care

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.

In our practice sequestration of the shafts of long bones in children because of acute osteomyelitis continues to be a problem. Conventional procedures for bone grafting are likely to fail. Vascularised grafts with microvascular anastomosis are technically demanding with a high rate of failure. Transfer of the rib on its vascular pedicle to achieve anterior fusion in the thoracic spine is now well established and the length of the pedicle available is adequate to allow grafting of a diaphyseal defect in the humerus. We describe the successful use of this procedure in two patients

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

The following preliminary conclusions seem possible. 1. In early cases of Pott's disease of the thoracic spine in children the treatment should include chemotherapy, recumbency and costo-transversectomy. An exception may be made if severe destruction has led to subluxation of the column, when more radical surgery is indicated. 2. Combination of conservative treatment with costo-transversectomy can prevent spread of the disease along the vertebral column, and can lead to regression of this "spondylitis anterior.". 3. The abscess can be totally eradicated and the risk of recrudescence therefore diminished

Twelve cases of sternal injury associated with spinal fractures have been reviewed. The sternum is regularly buckled or fractured in patients with high thoracic spinal fractures. Our review suggests that sternal injuries may also be associated with spinal fractures outside this region, and with types of fracture other than crushing of vertebral bodies. Injury to the sternum, when due to indirect violence, is almost always associated with a severe spinal column injury. A displaced fracture of the thoracic spine, with or without an associated sternal fracture, can produce significant widening of the mediastinal shadow on a chest radiograph. This is caused by a paravertebral haematoma, and can be difficult to differentiate from widening due to an aortic rupture

Aims

The aim of this study was to determine whether early surgical treatment results in better neurological recovery 12 months after injury than late surgical treatment in patients with acute traumatic spinal cord injury (tSCI).

Progressive structural scoliosis in growing rabbits has been produced. Tethering the thoracic spine into the form of an asymmetric lordosis produces a slowly progressive structural scoliosis by purely mechanical means. The addition of a contralateral release of the paraspinal muscles leads to a very progressive deformity with early cardiorespiratory failure. This release, however, was performed with an electric soldering iron and subsequent study showed that in those animals with severe progressive deformity there was localised spinal cord damage. We suggest that it is this neural damage and not the muscle release which leads to rapid progression. The clinical implications are important in that neurological dysfunction seems to render the spinal column less able to resist mechanical buckling and may be the crucial factor differentiating severely progressive from more benign curves

A new technique for the transthoracic removal of a prolapsed intervertebral disc in the mid or lower thoracic spine is described. Investigations before operation include thoracic myelography, selective spinal angiography and CT scanning. Image intensification is used at operation to check the level of the prolapse. A tunnel in the coronal plane (vertebrotomy) is made through the posterolateral part of the disc and the adjacent vertebral bodies, to reach the spinal canal at the site of the prolapse. This gives good exposure and enables gentle removal of the disc prolapse and any associated osteophytes, under direct vision without need for retraction or pressure on the dura or spinal cord. Spinal stability is not compromised, and the blood supply of the cord is not disturbed. Five consecutive patients are reported, including one in whom the disc prolapse was calcified and had herniated into the spinal cord. All were treated successfully

1. A forty-nine-year-old man had a chondrosarcoma arising from the body of the seventh thoracic vertebra. The tumour protruded into the mediastinum and also into the spinal canal where it displaced the spinal cord. 2. At operation all the seventh thoracic vertebra and parts of the sixth and eighth were removed together with the tumour. The thoracic spine was reconstructed by inserting two iliac bone-blocks between the cut bodies of the sixth and eighth vertebrae and by wiring two strong "A. O." plates to the transverse processes of the third to the sixth and the eighth to the tenth vertebrae. 3. The patient was nursed in a plaster-of-Paris bed for three and a half months. 4. One year and three months after operation, the patient was walking and well, with no signs of recurrence or metastasis. Radiographs showed that a block-vertebra had been created from the iliac grafts and the two cut vertebrae

Moire topography was added to school scoliosis screening in Singapore in 1982. The results from 1342 topographs, assessed in isolation, were used to study the accuracy of the method in predicting the radiographic location and magnitude of scoliotic curves. Accuracy in identifying the site of the curve was 68% in the thoracic spine, 54% in the thoracolumbar spine, and 15% in the lumbar region. There were 12.7% false-positive results and 4.3% false negatives. Of patients with a deviation of one moire fringe, 76.5% had a curve of 15 degrees or less; of those with a deviation of four moire fringes, 69% had a curve greater than 26 degrees. The prediction of the Cobb angle was less accurate when there was a deviation of two or three fringes. It is suggested that moire topography as a screening device should be reserved for use in the second tier of screening, since the forward-bending test is an effective and cheap method for the first tier of a mass school-screening programme

1. The results of 243 thoracoplasty operations are discussed. It was found that scoliosis developed in over 99 per cent of cases and that the curve was convex towards the side of operation. The angle of curvature correlated closely with the number of ribs removed. 2. If the head, neck and tubercle of the rib and the transverse process of the corresponding vertebra were all removed the degree of scoliosis was increased, whereas if a thoracoplasty was performed with apicolysis and embedding of the scapula the spinal deformity was less. Possible explanations for these phenomena are discussed. 3. No evidence was found to support the theory of causation by imbalance between the paired "pneumatic cylinders" (lungs and thoracic cage) supporting the thoracic spine. 4. The scoliosis was found to progress for many years; some factors influencing this course are discussed. 5. No correlation was found between the age of the patient at the time of thoracoplasty and the degree of subsequent scoliosis, but severe spinal deformity can arise even in older adults

We prospectively studied the use of intercostal EMG monitoring as an indicator of the accuracy of the placement of pedicle screws in the thoracic spine. We investigated 95 thoracic pedicles in 17 patients. Before insertion of the screw, the surgeon recorded his assessment of the integrity of the pedicle track. We then stimulated the track using a K-wire pedicle probe connected to a constant current stimulator. A compound muscle action potential (CMAP) was recorded from the appropriate intercostal or abdominal muscles. Postoperative CT was performed to establish the position of the screw. The stimulus intensity required to evoke a muscle response was correlated with the position of the screw on the CT scan. There were eight unrecognised breaches of the pedicle. Using 7.0 mA as a threshold, the sensitivity of EMG was 0.50 in detecting a breached pedicle and the specificity was 0.83. Thoracic pedicle screws were accurately placed in more than 90% of patients. EMG monitoring did not significantly improve the reliability of placement of the screw

Bone-marrow transplantation has increased the survival of patients with mucopolysaccharidosis-I. We describe the spinal problems and their management in 12 patients with this disorder who have been followed up for a mean of 4.5 years since transplantation. High lumbar kyphosis was seen in ten patients which was associated with thoracic scoliosis in one. Isolated thoracic scoliosis was seen in another. One patient did not have any significant problems in the thoracic or lumbar spine but had odontoid hypoplasia, which was also seen in three other children. Four of the eight patients in whom MRI of the cervical spine had been performed had abnormal soft tissue around the tip of the odontoid. Neurological problems were seen in two patients. In one it was caused by cord compression in the lower dorsal spine 9.5 years after posterior spinal fusion for progressive kyphosis, and in the other by angular kyphosis with thecal indentation in the high thoracic spine associated with symptoms of spinal claudication

From 1981 to 1986 we treated 413 patients for acute spinal-cord injuries. We reviewed 356 patients followed for a minimum of two years of whom 71 (20%) developed heterotopic ossification around one or more joints. Heterotopic ossification occurred more often in male patients (23%) than in female (10%), and was most frequent in the 20- to 30-year age group. It was also more common after injuries of the lower cervical or thoracic spine than after those of the lumbar spine. Patients with severe neurological deficits (Frankel grades A and B) showed significantly more heterotopic ossification but there was no correlation with the number or severity of associated head and limb injuries. Serum calcium levels did not change significantly in either group for 30 weeks after injury, but the erythrocyte sedimentation rate and the alkaline phosphatase level were significantly increased at six weeks in patients with heterotopic ossification

1. The radiological features of skeletal hydatid disease are discussed. Osseous lesions occur in about 1 to 2 per cent of cases, bone being involved only after the embryos have passed the filters provided firstly by the liver and secondly by the lungs. At first, ill defined areas of translucency appear which are not diagnostic. In developed lesions, clear-cut destructive areas, with a surrounding sclerotic reaction, become visible. The cysts thin and expand the cortex and tend to spread throughout an affected bone. In advanced stages the cortex is ruptured, and exuberant hydatid cyst growth takes place in the adjacent soft tissue. Around this an ectocyst forms, which may later calcify, indicating death of the parasite. The progress of the disease is very slow. 2. Three cases of affection of the thoracic spine are described, and the differential diagnosis is considered, particularly from plasmacytoma and neurofibroma. Each case presented with cord pressure symptoms. Operative decompression relieved these totally in one case, incompletely in another, and not at all in the third and most advanced case. 3. With rapid and easy travel in the modern world hydatid disease is liable to be seen in areas where it is not endemic

1. Since the publication by Bradford and Spurling in 1945 of The Intervertebral Disc, there has been argument about the figure of 1,600 pounds that they calculated as the load on each lower lumbar intervertebral disc when a person lifts a heavy load with the trunk flexed, especially since experiments have shown that intervertebral discs subjected to increasing pressures yield at values well below this figure. In the author's experiments the discs were destroyed by pressures ranging from 350 to 1,400 pounds, with a mean of 710 pounds. 2. It occurred to the writer that the spine is not necessarily the only structure in the body that can transmit pressure forces from the shoulder to the pelvis. A raised intra-abdominal pressure impacts a thrust under the diaphragm, which will be transmitted to the thoracic spine and the shoulders by means of the ribs. This thrust can take care of part of the lifted weight and thus decrease the load on the spine. 3. In experiments in which the intra-abdominal pressure was measured by means of a small balloon in the stomach it was found that the pressure rose proportionally with the amount of weight lifted. 4. It is suggested that the abdominal fluid ball can exert a longitudinal force only if there is no contraction of the longitudinal muscles (at least anteriorly). Electromyographic studies of the abdominal muscles during weight lifting showed that the transverse and possibly the oblique abdominal muscles contract, but not the recti. 5. It thus seems that the load on the intervertebral discs is not necessarily so great as Bradford and Spurling calculated, but can remain within safe limits. It is hard to give accurate figures for the amount of load that is taken off the spine in this way, but an estimate would put it at several hundred pounds. The importance of a reflex contraction of the abdominal wall during effort as a protective mechanism for the spine must therefore be appreciated. Voluntary contraction may also be called upon to increase the intra-abdominal pressure and so reduce the load on the discs. This is done by many weight lifters

1. Details are given of sixty-three consecutive cases with a history of pleural effusion seen at an orthopaedic hospital. 2. Twenty-four of these were post-primary effusions occurring before the onset of symptoms of the orthopaedic lesion. The bone and joint lesions ultimately developing in this group of patients were widely scattered throughout the skeleton. 3. Three others were secondary to adult-type pulmonary lesions. 4. Thirty-six patients had a pleural effusion after the beginning of their orthopaedic tuberculous history. Seven were certainly secondary to operative intervention, six in the thorax near the parietal pleura (costotransversectomy or antero-lateral decompression of the cord) and one from a haematogenous dissemination after fusion of a hip joint. 5. The remainder of this group with pleural effusion during the history of their orthopaedic tuberculous disease numbered twenty-nine. Of these, twenty-five suffered from disease of the thoracic spine; in two more details are defective. Only two definitely had neither pulmonary nor thoracic spinal disease; their lesions were in the lumbar spine. The conclusion is drawn that the overwhelmingly common cause of pleural effusion in patients with orthopaedic tuberculosis who have normal lungs and have not recently suffered spinal decompression is transpleural infection from thoracic spinal disease and that the sequence is by no means rare. It had occurred in approximately one in six of 145 patients with thoracic Pott's disease seen during this investigation. 6. Details are given of a group of cases with thoracic paravertebral abscess tracking laterally. When the abscess is well clear of the spine and spinal ligaments it may project forwards and radiologically it may appear in the antero-posterior chest film as a shadow in the middle of one or other lung field rather than as a shadow obviously connected with the central paravertebral abscess. Aspiration will yield pus from this posterior extra-pleural abscess extension. 7. The belief that Pott's disease most commonly follows direct spread from caseous paraaortic glands secondary to tuberculous pleurisy is discussed. It is concluded that the evidence is insufficient for so sweeping a statement

1. Compression forces are mainly absorbed by the vertebral body. The nucleus pulposus, being liquid, is incompressible. The tense annulus bulges very little. On compression the vertebral end-plate bulges and blood is forced out of the cancellous bone of the vertebral body into the perivertebral sinuses. This appears to be the normal energy-dissipating mechanism on compression. 2. The normal disc is very resistant to compression. The nucleus pulposus does not alter in shape or position on compression or flexion. It plays no active part in producing a disc prolapse. On compression the vertebral body always breaks before the normal disc gives way. The vertebral end-plate bulges and then breaks, leading to a vertical fracture. If the nucleus pulposus has lost its turgor there is abnormal mobility between the vertebral bodies. On very gentle compression or flexion movement the annulus protrudes on the concave aspect–not on the convex side as has been supposed. 3. Disc prolapse consists primarily of annulus; it occurs only if the nucleus pulposus has lost its turgor. It then occurs very easily as the annulus now bulges like a flat tyre. 4. I have never succeeded in producing rupture of normal spinal ligaments by hyperextension or hyperflexion. Before rupture occurs the bone sustains a compression fracture. On the other hand horizontal shear, and particularly rotation forces, can easily cause ligamentous rupture and dislocation. 5. A combination of rotation and compression can produce almost every variety of spinal injury. In the cervical region subluxation with spontaneous reduction can be easily produced by rotation. If disc turgor is impaired this may occur with an intact anterior longitudinal ligament and explains those cases of tetraplegia without radiological changes or a torn anterior longitudinal ligament. The anterior longitudinal ligament can easily be ruptured by a rotation force and in my experience the so-called hyperextension and hyperflexion injuries are really rotation injuries. 6. Hyperflexion of the cervical spine or upper thoracic spine is an anatomical impossibility. In all spinal dislocations a body fracture may or may not occur with the dislocation, depending upon the degree of associated compression. In general, rotation forces produce dislocations, whereas compression forces produce fractures

Aims

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

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.

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The aim of this retrospective study was to compare the correction achieved using a convex pedicle screw technique and a low implant density achieved using periapical concave-sided screws and a high implant density. We hypothesized that there would be no difference in outcome between the two techniques.

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This study, using a surgeon-maintained database, aimed to explore the risk factors for surgery-related complications in patients undergoing primary cervical spine surgery for degenerative diseases.

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To report the mid-term results of a modified self-growing rod (SGR) technique for the treatment of idiopathic and neuromuscular early-onset scoliosis (EOS).

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Early cases of cauda equina syndrome (CES) often present with nonspecific symptoms and signs, and it is recommended that patients undergo emergency MRI regardless of the time since presentation. This creates substantial pressure on resources, with many scans performed to rule out cauda equina rather than confirm it. We propose that compression of the cauda equina should be apparent with a limited sequence (LS) scan that takes significantly less time to perform.

Aims

The direct posterior approach with subperiosteal dissection of the paraspinal muscles from the vertebrae is considered to be the standard approach for the surgical treatment of adolescent idiopathic scoliosis (AIS). We investigated whether or not a minimally-invasive surgery (MIS) technique could offer improved results.

Aims

Intraoperative 3D navigation (ION) allows high accuracy to be achieved in spinal surgery, but poor workflow has prevented its widespread uptake. The technical demands on ION when used in patients with adolescent idiopathic scoliosis (AIS) are higher than for other more established indications. Lean principles have been applied to industry and to health care with good effects. While ensuring optimal accuracy of instrumentation and safety, the implementation of ION and its associated productivity was evaluated in this study for AIS surgery in order to enhance the workflow of this technique. The aim was to optimize the use of ION by the application of lean principles in AIS surgery.