In type-II fractures of the odontoid process, the treatment is either conservative in a halo vest or primary surgical stabilisation. Since nonunion, requiring prolonged immobilisation or late surgery, is common in patients treated in a halo vest, the identification of those in whom this treatment is likely to fail is important.

We reviewed the data of 69 patients with acute type-II fractures of the odontoid process treated in a halo vest. The mean follow-up was 12 months. Conservative treatment was successful, resulting in bony union in 32 (46%) patients. Anterior dislocation, gender and age were unrelated to nonunion. However, nonunion did correlate with a fracture gap (> 1 mm), posterior displacement (> 5 mm), delayed start of treatment (> 4 days) and posterior redisplacement (> 2 mm).

We conclude that patients presenting with these risk factors are unlikely to achieve bony union by treatment in a halo vest. They deserve careful attention during the follow-up period and should also be considered as candidates for primary surgical stabilisation.

We reviewed 64 anterolateral decompressions performed on 63 patients with tuberculosis of the dorsal spine (D₁ to L₁). The mean age of the patients was 35 years (9 to 73) with no gender preponderance. All patients had severe paraplegia (two cases grade III, 61 cases grade IV). The mean number of vertebral bodies affected was 2.6; the mean pre-treatment kyphosis was 24.8° (7 to 84). An average of 2.9 ribs were removed in the course of 64 procedures. The mean time taken at surgery was 2.45 hours when two ribs were removed and 3.15 hours when three ribs were removed. Twelve patients (19%) showed signs of neurological recovery within seven days, 33 patients (52%) within one month and 12 patients (19%) after two months; but six patients (10%) showed no neurological recovery. Forty patients were followed up for more than two years. In 34 (85%) of these patients there was no significant change in the kyphotic deformity; two patients (5%) showed an increase of more than 20°.

Two collagen type IX gene polymorphisms that introduce a tryptophan residue into the protein’s triple-helical domain have been linked to an increased risk of lumbar disc disease. To determine whether a particular subset of symptomatic lumbar disease is specifically associated with these polymorphisms, we performed a prospective case-control study of 107 patients who underwent surgery of the lumbar spine. Patients were assigned to one of five clinical categories (fracture, disc degeneration, disc herniation, spinal stenosis without spondylolisthesis and spinal stenosis with spondylolisthesis) based on history, imaging results, and findings during surgery. Of the 11 tryptophan-positive patients, eight had spinal stenosis with spondylolisthesis and three had disc herniation. The presence of the tryptophan allele was significantly associated with African-American or Asian designation for race (odds ratio 4.61, 95% CI 0.63 to 25.35) and with the diagnosis of spinal stenosis with spondylolisthesis (odds ratio 6.81, 95% CI 1.47 to 41.95).

Our findings indicate that tryptophan polymorphisms predispose carriers to the development of symptomatic spinal stenosis associated with spondylolisthesis which requires surgery.

We describe five patients with cervical spondylosis and large anterior osteophytes causing pharyngeal compression. All had dysphagia, two had obstructive sleep apnoea and another two had dyspnoea and stridor on inspiration. One, with perforation of the pharynx, required emergency tracheostomy. Only three had pain in the neck or arm.

Compression of the retroglottic space was confirmed in all patients by pharyngoscopy and in all the symptoms were relieved by excision of the osteophytes. Three also underwent intervertebral fusion. One had some persistent sleep apnoea.

The National Inpatient Register and the Swedish Death Register were linked to determine the incidence of surgical intervention, the trends and characteristics of the patients, the death rate and the pre- and post-operative admissions for herniation of a lumbar disc based on comprehensive national data between 1987 and 1999.

There were 27 576 operations which were followed cumulatively for 155 249 years, with a median of 6.0 years. The mean annual rate of operation was 24 per 100 000 inhabitants, the median age of the patients was 42 years. The 30-day death rate was 0.5 per 1000 operations. The rates of re-operation at one and ten years were 5% and 10%, respectively, decreasing significantly (40%) with time. The mean length of stay decreased from nine to five days. Patients who had been in hospital because of a previous spinal disorder had a significantly higher risk of readmission.

A consecutive series of 85 patients with Duchenne’s muscular dystrophy who underwent spinal fusion over a period of 16 years was followed up with regard to the progression of the scoliosis and pelvic obliquity. Of 74 patients with adequate radiographic follow-up, 55 were instrumented with the Luque single-unit rod system and 19 with the Isola pedicle screw system; seven were instrumented to L3/4, 42 to L5, 15 to S1 and 10 to the pelvis with intrailiac rods.

The mean period of follow-up was 49 months (SD 22) before and 47 months (SD 24) after operation. There was one peri-operative death and three cases of failure of hardware.

The mean improvement in the Cobb angle was 26° and in pelvic obliquity, 9.2°.

Fusion to L3/4 achieved a poorer correction of both curves while intrapelvic rods, achieved and maintained the best correction of pelvic obliquity. Fusion to S1 did not provide any benefit over more proximal fusion excluding the sacrum, with regard to correction and maintenance of both angles. The Isola system appeared to provide and maintain a slightly better correction of the Cobb angle.

The optimum timing of lumbar discectomy for sciatica is imprecise. We have investigated a number of prognostic factors in relation to the outcome of radiculopathy after lumbar discectomy. We recruited 113 consecutive patients of whom 103 (91%) were followed up at one year. We found a significant association between the duration of radiculopathy and the changes in the Oswestry Disability Index score (p = 0.005) and the low back outcome score (p = 0.03). Improvement in pain was independent of all variables. Patients with an uncontained herniated disc had a shorter duration of symptoms and a better functional outcome than those with a contained herniation.

Our study suggests that patients with sciatica for more than 12 months have a less favourable outcome. We detected no variation in the results for patients operated on in whom the duration of sciatica was less than 12 months.

Lumbar spondylolysis can heal with conservative treatment, but few attempts have been made to identify factors which may affect union of the defects in the pars. We have evaluated, retrospectively, the effects of prognostic variables on bony union of pars defects in 134 young patients less than 18 years of age with 239 defects of the pars who had been treated conservatively. All patients were evaluated by CT scans when first seen and more than six months later at follow-up.

The results showed that the spinal level and the stage of the defects were the predominant factors. The site of the defects in the pars, the presence or development of spondylolisthesis, the condition of the contralateral pars, the degree of lumbar lordosis and the degree of lumbar inclination all significantly affected union.

We undertook a radiographic analysis with pre-operative computed tomographic myelography in 78 patients with idiopathic scoliosis in order to analyse rotation of the spinal cord and to investigate its clinical significance. The angle of rotation of the cord had a statistically significant relationship to both that of the apical vertebra and the size of the primary curve. The relationship between the rotation of the cord and that of the apical vertebra was divided into three types. The cord rotated in the same direction as the apical vertebra in 55 patients and rotated in the opposite direction in the remaining 23 patients. In the first group, the angle of rotation of the cord was more than that of the vertebra in six patients, but less than it in 49 patients. These results suggest that the neuraxis in idiopathic scoliosis may be under tension in the axial dimension.

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

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

Between 1995 and 1999, 12 patients aged 65 years or more (mean 70.2) with lumbar disc herniation, underwent partial laminectomy and nucleotomy. The results were compared with those of 25 younger patients aged between 20 and 40 years (mean 30.1), who underwent the same surgical procedure. The Japanese Orthopedic Association (JOA) score was used to assess the clinical outcome. The minimum follow-up was 12 months. The pre- and post-operative total JOA scores and the rate of improvement of the JOA score were not significantly different between the elderly (11.1, 24.3 points, and 74.1%), and the younger group (11.6, 26.4 points and 84.5%).

The results of this study indicate that the outcome of lumbar discectomy in elderly patients is as good as in younger patients.

We measured the serum concentration of C-reactive protein (CRP) by a high-sensitive method in patients with lumbar disc herniation. There were 48 patients in the study group and 53 normal controls. The level and type of herniation were evaluated. The clinical data including the neurological findings, the angle of straight leg raising and post-operative recovery as measured by the Japanese Orthopaedic Association (JOA) score, were recorded. The high-sensitive CRP (hs-CRP) was measured by an ultrasensitive latex-enhanced immunoassay. The mean hs-CRP concentration was 0.056 ± 0.076 mg/dl in the patient group and 0.017 ± 0.021 mg/dl in the control group. The difference was statistically significant (p = 0.006). There was no other correlation between the hs-CRP concentration and the level and type of herniation, or the pre-operative clinical data. A positive correlation was found between the concentration of hs-CRP before operation and the JOA score after. Those with a higher concentration of hs-CRP before operation showed a poorer recovery after. The significantly high concentration of serum hs-CRP might indicate a systemic inflammatory response to impingement of the nerve root caused by disc herniation and might be a predictor of recovery after operation.

We studied the use of autologous pre-donated blood transfusion in surgery for scoliosis in 45 patients who were divided into two groups; 27 who pre-donated autologous blood (group 1) and 18 who were planned recipients of allogenic blood (group 2). Normovolaemic haemodilution and intra-operative blood salvage was used in six patients in group 1 and three patients in group 2.

The two groups did not differ significantly with respect to age, American Society of Anaesthesiologists score, mean operative time, number of vertebral segments fused, total blood loss, length of stay in intensive care and length of stay in hospital. The risk of requiring allogenic blood transfusion was found to be significantly less in group 1 (7.4% ν 88.9%, p < 0.001). Only 5.21% of autologous units were wasted. Although intra-operative blood salvage reduced the total blood loss in both groups, it did not affect the need for subsequent allogenic transfusion or reduce the number of pre-donated autologous units which were given (p < 0.67). Autologous blood transfusion required extra time, personnel, resources and cost £28.88 per patient more than allogenic transfusion, however, the projected costs at May 2002 make this programme cost-effective by £51.54 per patient.

Pre-donated autologous blood transfusion is acceptable and safe in scoliosis surgery. It significantly reduces the subsequent requirement of allogenic transfusion. Although the cost is currently more than allogenic transfusion, with the increase in the costs of the latter and the decrease in potential donors which is anticipated, pre-donation of autologous blood will become comparatively cost-effective.

We undertook a comparative study of magnetic resonance imaging (MRI) vertebral morphometry of thoracic vertebrae of girls with adolescent idiopathic thoracic scoliosis (AIS) and age and gender-matched normal subjects, in order to investigate abnormal differential growth of the anterior and posterior elements of the thoracic vertebrae in patients with scoliosis. Previous studies have suggested that disproportionate growth of the anterior and posterior columns may contribute to the development of AIS. Whole spine MRI was undertaken on 83 girls with AIS between the age of 12 and 14 years, and Cobb’s angles of between 20° and 90°, and 22 age-matched controls. Multiple measurements of each thoracic vertebra were obtained from the best sagittal and axial MRI cuts. Compared with the controls, the scoliotic spines had longer vertebral bodies between T1 and T12 in the anterior column and shorter pedicles with a larger interpedicular distance in the posterior column. The differential growth between the anterior and the posterior elements of each thoracic vertebra in the patients with AIS was significantly different from that in the controls (p < 0.01). There was also a significant positive correlation between the scoliosis severity score and the ratio of differential growth between the anterior and posterior columns for each thoracic vertebra (p < 0.01). Compared with age-matched controls, the longitudinal growth of the vertebral bodies in patients with AIS is disproportionate and faster and mainly occurs by endochondral ossification. In contrast, the circumferential growth by membranous ossification is slower in both the vertebral bodies and pedicles.

We conducted a prospective, randomised study of 42 cervical interbody fusions undertaken with either an autologous tricortical graft or a cage. The factors assessed in the two groups were: (1) time taken to achieve fusion; (2) neck disability index; (3) pain score; (4) interbody height ratio; (5) interbody angle and (6) the influence of smoking on fusion.

No statistical difference was seen in the time taken to achieve fusion, neck disability index, interbody height ratio, or interbody angles. Smoking did not have any effect on the fusion process. The pain score was significantly lower in the tricortical graft group at six months. We conclude that both methods of fusion give similar results, although tricortical graft fusion is cheaper than cage fusion, and is more effective in reducing the pain score.

We present four patients who had sustained a traumatic dislocation of the atlanto-occipital joint. The diagnosis was initially missed in two patients. One patient, who was neurologically intact, was treated non-operatively. The remaining three recovered neurologically after an occipitocervical fusion. Early recognition of the injury, especially in multiply-injured patients with head injuries, and timely management may improve survival and neurological recovery.

We examined the pathogenesis of Schmorl’s nodes, correlating the histological findings from 12 lumbar vertebrae with the corresponding conventional radiographs, tomographs, MR images and CT scans. The last revealed round, often multiple cystic lesions with indistinct sclerotic margins beneath the cartilaginous endplate. The appearances are similar to the typical CT changes of osteonecrosis. Histological examination of en-bloc slices through Schmorl’s nodes gave clear evidence of subchondral osteonecrosis. Beneath the cartilage endplate, we found fibrosis within the marrow cavities with the disappearance of fat cells. Osteocytes within bone trabeculae were either dead or had disappeared. We suggest that Schmorl’s nodes are the end result of ischaemic necrosis beneath the cartilaginous endplate and that herniation into the body of the vertebra is secondary.

We present a review of 553 patients who underwent surgery for intractable sciatica ascribed to prolapsed lumbar intervertebral disc. One surgeon in one institution undertook or supervised all the operations over a period of 16 years.

The total number of primary discectomies included in the study was 531, of which 42 subsequently required a second operation for recurrent sciatica, giving a revision rate of 7.9%. Factors associated with reoperation were analysed. A contained disc protrusion was almost three times more likely to need revision surgery, compared with extruded or sequestrated discs. Patients with primary protrusions had a significantly greater straight-leg raise and reduced incidence of positive neurological findings compared with those with extruded or sequestrated discs. These patients should therefore be selected out clinically and treated by a more enthusiastic conservative programme, since they are three times more likely to require revision surgery.

In order to determine the influence of early ambulation and other factors on headaches occurring after lumbar myelography we randomised 207 patients (127 men and 80 women) into two groups. Following the investigation, we allowed the 101 patients (65 men and 36 women) in group A to sit or stand freely, while we confined the 106 patients (62 men and 44 women) in group B to bed for 20 hours. The nine patients in group B who could not maintain bed rest were excluded.

There was no significant difference between the two groups as regards the prevalence of spinal headache (8.9% in group A v 14.4% in group B). Patients who reported headaches, however, were significantly more likely to be women (18.7%) than men (7.3%), be younger (mean age 45 years v 56 years), have a higher cerebrospinal pressure before removal of fluid (mean values 172 v 137 mm H₂O) and a lower systolic (mean values 120 v 134 mmHg) and diastolic blood pressure.

We conclude that, although other factors may be associated with headaches, late ambulation is not effective in preventing spinal headaches after lumbar myelography.

Studies on recurrent disc herniation quote rates of recurrence without regard to the times of recurrence and the influence of longer follow-up. Our objective was to assess the use of survival analysis to measure the rate of revision after lumbar microdiscectomy. We undertook a retrospective analysis of the hospital records of 993 patients who underwent lumbar microdiscectomy over a period of ten years. After calculating the overall rate of revision for the mean length of follow-up, we carried out a survival analysis using the life-table method. During the study period 49 patients had a revision microdiscectomy. This gave an overall rate of revision of 4.9% at a mean follow-up of 5.25 years. Using survival analysis, the rate of revision was 7.9% at a follow-up of ten years when the number at risk was 84. Survival analysis gives a more accurate estimation of the true rate of recurrence for patients undergoing lumbar microdiscectomy. The method allows better comparison between different interventions for disc herniation.

We studied prospectively 22 young athletes who had undergone surgical treatment for lumbar spondylolysis. There were 15 men and seven women with a mean age of 20.2 years (15 to 34). Of these, 13 were professional footballers, four professional cricketers, three hockey players, one a tennis player and one a golfer. Preoperative assessment included plain radiography, single positron-emission CT, planar bone scanning and reverse-gantry CT. In all patients the Oswestry disability index (ODI) and in 19 the Short-Form 36 (SF-36) scores were determined preoperatively, and both were measured again after two years in all patients. Three patients had a Scott’s fusion and 19 a Buck’s fusion.

The mean duration of back pain before surgery was 9.4 months (6 to 36). The mean size of the defect as determined by CT was 3.5 mm (1 to 8) and the mean preoperative and postoperative ODIs were 39.5 (sd 8.7) and 10.7 (sd 12.9), respectively. The mean scores for the physical component of the SF-36 improved from 27.1 (sd 5.1) to 47.8 (sd 7.7). The mean scores for the mental health component of the SF-36 improved from 39.0 (sd 3.9) to 55.4 (sd 6.3) with p < 0.001. After rehabilitation for a mean of seven months (4 to 10) 18 patients (82%) returned to their previous sporting activity.

We have studied 58 patients with pain from osteoporotic vertebral fractures which did not respond to conservative treatment. These were 53 women and five men with a mean age of 72.5 years. They received a nerve-root injection with lidocaine, bupivicaine and DepoMedrol. The mean follow-up period was 13.5 months.

The mean pain scores before treatment, at one and six months after treatment and at the final follow-up were 85, 24.9, 14.1, and 17.4, respectively. According to our modified criteria for grading results, six patients were considered to have an excellent result, 42 good and ten fair. A newly developed compression fracture was noted in three patients. There were no complications related to the injection.

Our study suggests that nerve-root injections are effective in reducing pain in patients with osteoporotic vertebral fractures and that these patients should be considered for this treatment before percutaneous vertebroplasty or operative intervention is attempted.

We analysed the CT scans and radiographs of 76 vertebrae in 49 patients who underwent vertebroplasty for painful osteoporotic compression fractures. Leaks of cement were classified into three types: those via the basivertebral vein (type B), via the segmental vein (type S), and through a cortical defect (type C).

More leaks were identified on CT scans than on radiographs by a factor of 1.5 (74/49). Most type-B (93%) and type-S (86%) leaks were missed or underestimated on a lateral radiograph which is usually the only view used during the injection of cement. Of the leaks into the spinal canal, only 7% (2/28) were correctly identified on radiographs. The areas on lateral radiographs where this type of leak may be observed were divided into four zones, and their diagnostic value in predicting a leak into the spinal canal was evaluated. The results showed that cement in the neural foramina had the highest positive predictive value (86%).

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.

Degenerative changes of the knee often cause loss of extension. This may affect aspects of posture such as lumbar lordosis. A total of 366 patients underwent radiological examination of the lumbar spine in a standing position. The knee and body angles were measured by physical examination using a goniometer. Limitation of extension of the knee was significantly greater in patients whose lumbar lordosis was 30° or less. Lumbar lordosis was significantly reduced in patients whose limitation of extension of the knee was more than 5°. It decreased over the age of 70 years, and the limitation of extension of the knee increased over the age of 60 years. Our study indicates that symptoms from the lumbar spine may be caused by degenerative changes in the knee. This may be called the ‘knee-spine syndrome’.

Intraoperative pulmonary fat and bone-marrow embolism is a serious complication of bone and joint surgery. We have investigated the occurrence and incidence of intraoperative embolism in patients undergoing elective lumbar spinal surgery with or without instrumentation.

Sixty adult patients with lumbar degenerative disease were examined by intraoperative transoesophageal echocardiography while undergoing posterior lumbar surgery. Of these, 40 underwent surgery with instrumentation and 20 without.

Moderate to severe (grade 2 or 3 according to the grading scale of Pitto et al) embolic events were seen in 80% of the instrumented patients but in none of the non-instrumented patients (p < 0.001). The insertion of pedicle screws was particularly associated with large numbers of pulmonary emboli, while the surgical approach, laminectomy, disc removal and bone harvesting were associated with small numbers of emboli.

We consider that, as in arthroplasty and intramedullary fixation of fractures, these embolic events are relevant to the development of potentially fatal fat embolism during spinal surgery.

We have studied, prospectively, 116 patients with motor deficits associated with herniation of a lumbar disc who underwent microdiscectomy. They were studied during the first six months and at a mean of 6.4 years after surgery. Before operation, muscle weakness was mild (grade 4) in 67% of patients, severe (grade 3) in 21% and very severe (grade 2 or 1) in 12%. The muscle which most frequently had severe or very severe weakness was extensor hallucis longus, followed in order by triceps surae, extensor digitorum communis, tibialis anterior, and others.

At the latest follow-up examination, 76% of patients had complete recovery of strength. Persistent weakness was found in 16% of patients who had had a mild preoperative deficit and in 39% of those with severe or very severe weakness. Muscle strength was graded 4 in all patients with persistent weakness, except for four with a very severe preoperative deficit affecting the L5 or S1 nerve root. They showed no significant recovery. Excluding this last group, the degree of recovery of motor function was inversely related to the preoperative severity and duration of muscle weakness. The patients’ subjective functional capacity was not directly related to the degree of recovery except in those with persistent severe or very severe deficit.

Antibiotics are often administrated prophylactically in spinal procedures to reduce the risk of infection of the disc space. It is still not known which antibiotics are able to penetrate the intervertebral disc effectively. In a prospective, randomised, double-blind clinical study, we examined the penetration of the intervertebral discs of two commonly used antibiotics, cefuroxime and gentamicin. The patients, randomised into two groups, received either 1.5 g of cefuroxime or 5 mg/kg of gentamicin prophylactically two hours before their intervertebral discs were removed. A specimen of blood, from which serum antibiotic levels were determined, was obtained at the time of discectomy.

Therapeutic levels of antibiotic were detectable in the intervertebral discs of the ten patients who received gentamicin. Only two of the ten patients (20%) who received cefuroxime had a quantifiable level of antibiotic in their discs although therapeutic serum levels of cefuroxime were found in all ten patients. Our results show that cefuroxime does not diffuse into human intervertebral discs as readily as gentamicin. It is possible that the charge due to ionisable groups on the antibiotics can influence the penetration of the antibiotics. We therefore recommend the use of gentamicin in a single prophylactic dose for all spinal procedures in order to reduce the risk of discitis.

Of 42 patients with resolvingscoliosis, 34 were followed up for more than 25 infantile idiopathicyears. Twenty had been primarily treated in a plaster bed and 14 by physiotherapy. The mean angle of the curve at presentation was 17° and at follow-up it was 5°. No patient had significant progression of the scoliosis during the growth spurt. When adults few had back pain or an increased disability score and there was no interference with work or social activities. The rib-vertebra angle difference proved to be an essential radiological sign when distinguishing resolving from progressive infantile idiopathic scoliosis. There was no advantage of plaster over physiotherapy with regard to either the time to resolution or the functional outcome. Treatment of resolving infantile idiopathic scoliosis in a plaster bed is therefore now outdated.

We carried out a cadaver study of 16 iliolumbar veins in order to define the surgical anatomy. Two variants were found; a single vein at a mean distance of 3.74 cm from the inferior vena cava (11 of 16) and two separate draining veins at a mean distance from the vena cava of 2.98 cm for the proximal and 6.24 cm for the distal stem (5 of 16). Consistently, the proximal vein tore on attempted medial retraction of the great vessels. The mean length of the vein was 1.6 cm and its mean width 1.07 cm. Three stems were shorter than 0.5 cm. Two or more tributaries usually drained the iliacus and psoas muscles, and the fifth lumbar vertebral body. The obturator nerve crossed all veins superficially at a mean of 2.76 cm lateral to the mouth. In four of these, this distance was less than 1.5 cm. Usually, the lumbosacral trunk crossed deep, at a mean distance of 2.5 cm lateral to the mouth, but in three veins, this distance was 1 cm or less.

Our findings emphasise the need for proper dissection of the iliolumbar vein before ligature during exposure of the anterior lumbar spine.

The systemic arterial pressure has been used as a guide for determining the susceptibility to surgical bleeding during controlled hypotensive anaesthesia. Arterial hypotension is not, however, necessarily accompanied by venous or intraosseous hypotension. The main source of bleeding during posterior spinal surgery is the bone and is venous rather than arterial.

The intraoperative blood loss, the intraosseous pressure (IOP) within the first thoracic vertebral body, and the systemic arterial pressure were measured in 27 patients during cervical laminoplasty for spondylotic myelopathy. The intraoperative blood loss correlated significantly with the vertebral IOP (p = 0.0073, r = 0.499), but not with systemic arterial pressure, age, or body-weight. The systemic arterial pressure did not correlate with the vertebral IOP. The mean value of the mean arterial pressure throughout the operation varied between 74 and 110 mmHg.

The findings suggest that the vertebral IOP parallels surgical bleeding during posterior spinal surgery under normotensive anaesthesia and that patients with a low arterial pressure do not necessarily have a low IOP.

We have reviewed, retrospectively, 66 adult patients who were treated for lumbar or lumbosacral tuberculosis. A total of 45 had a paravertebral or epidural abscess, 24 had clinical instability and 18 presented with a radiculopathy, of which six also had a motor deficit. The diagnosis was usually made on clinical and radiological grounds and they were followed up until there were clinical and radiological signs of full recovery.

Conservative treatment with antituberculous drugs was successful in 55 patients (83%). None had persistent instability, radiculopathy or neurological compromise. We feel that tuberculous spondylodiscitis, especially in the lumbar spine, can usually be satisfactorily managed conservatively and that there are few indications for surgical treatment.

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.

We investigated the effects of hydroxyapatite (HA) coating on the purchase of pedicle screws. A total of 23 consecutive patients undergoing lumbar fusion was randomly assigned to one of three treatment groups. The first received uncoated stainless-steel screws, the second screws which were partly coated with HA, and the third screws which were fully coated. The insertion torque was recorded. After 11 to 16 months, 21 screws had been extracted. The extraction torque was recorded. Radiographs were taken to assess fusion and to detect loosening of the screws.

At removal, the extraction torques exceeded the upper limit of the torque wrench (600 Ncm) for many HA-coated screws. The calculated mean extraction torque was 29 ± 36 Ncm for the uncoated group, 447 ± 114 Ncm for the partly-coated group and 574 ± 52 Ncm for the fully-coated group. There were significant differences between all three groups (p < 0.001). There were more radiolucent zones surrounding the uncoated screws than the HA-coated screws (p < 0.001). HA coating of pedicle screws resulted in improved fixation with reduced risk of loosening of the screws.

We have investigated whether patients with adolescent-onset idiopathic scoliosis (AIS) are more likely to have a low body-weight. Measurements of weight, height and body mass index (BMI) were made in 44 young women with AIS and compared with age- and gender-adjusted normative data. The body mass criteria of the International Classification of Diseases for eating disorders was used to determine how many patients were within the range considered to be ‘eating disordered’. Compared with the normative data, the AIS group did not differ significantly in terms of height, (p = 0.646), but they were significantly lighter (p < 0.001) and had significantly lower BMI scores (p < 0.001); 25% of the series had BMI scores which were within the range considered to be anorexic.

The relationship between a diagnosis of AIS and low body-weight may indicate disordered eating and is thus a cause for concern, particularly in the light of the well-established relationship between eating psychopathology and osteoporosis. Aspects of organic health may need to be considered in addition to the cosmetic deformity.

We have assessed the influence of somatisation on the outcome of treatment in 81 patients with chronic low back pain.

All, irrespective of whether treatment was surgical or conservative, had a significantly better (p < 0.001) health-related quality of life at follow-up on all but one scale of the SF-36. Lower health-related quality of life at follow-up correlated significantly with a higher tendency to somatise before treatment and at follow-up. A logistic regression analysis yielded two factors which predicted the outcome; somatisation (p < 0.001) and ‘doctor shopping’ (the number of physicians consulted before the present inpatient treatment, p < 0.001). These factors accurately distinguished between patients with good and those with poor outcomes in 82%. Patients with somatisation and ‘doctor shopping’ were at a higher risk for a poor outcome. The results show the relevance of somatisation in the outcome of treatment in patients with low back pain.

Herniated intervertebral disc tissue has been shown to produce a number of proinflammatory mediators and cytokines, but there have been no similar studies using discs from patients with discogenic low back pain.

We have compared the levels of production of interleukin-6 (IL-6), interleukin-8 (IL-8) and prostaglandin E₂ (PGE₂) in disc tissue from patients undergoing discectomy for sciatica (63) with that from patients undergoing fusion for discogenic low back pain (20) using an enzyme-linked immunoabsorbent assay.

There was a statistically significant difference between levels of production of IL-6 and IL-8 in the sciatica and low back pain groups (p < 0.006 and p < 0.003, respectively).

The high levels of proinflammatory mediator found in disc tissue from patients undergoing fusion suggest that production of proinflammatory mediators within the nucleus pulposus may be a major factor in the genesis of a painful lumbar disc.

Transitional vertebrae (TV) may be one of the risk factors for lumbar disc herniation. It is not clear, however, whether the presence of TV can affect the development of nerve-root symptoms. Our aim was to clarify this relationship. A total of 501 patients with lumbar degenerative disease and nerve-root symptoms was studied in respect of their level and the presence of TV. As a control group, 508 patients without low back pain or nerve-root symptoms were studied to establish the incidence of TV. In patients with disc herniation, the incidence was statistically higher and the mean age lower in patients with TV than in those without. In most patients, the symptomatic disc level was just above the TV. Similarly, in those with stenosis of the spinal canal without spondylolisthesis, the symptomatic disc level was most commonly just above the TV.

We have investigated the effect of multisegmental spinal fusion on the long-term functional and radiological outcome in patients with scoliosis. We compared these patients both with those whose spine had not been fused, and with a control group.

We studied 68 patients with idiopathic scoliosis (34 operative and 34 non-operative) who had been followed up for a minimum of five years after treatment. They were matched for age (mean 44 years) and Cobb angle (mean 54°) at follow-up. An age- and gender-matched control group of 34 subjects was also recruited.

All participants completed a questionnaire to assess spinal function and to grade the severity of back pain using a numerical rating scale. Radiographs of the spine were taken in the patients with scoliosis and lumbar degenerative changes were recorded.

The spinal function scores for the patients with scoliosis who had had a fusion were similar to those who had not. Both scoliosis groups, however, had lower scores than the control group (p < 0.001). The frequency and severity of back pain were lower for patients with scoliosis and fusion than for those without, but higher for both scoliosis groups compared with the control group. Radiographs showed similar degenerative changes in both scoliosis groups.

We carried out a retrospective review of 155 patients with lumbar spinal stenosis who had been treated surgically and followed up regularly: 77 were evaluated at a mean of 6.5 years (5 to 8) after surgery by two independent observers. The outcome was assessed using the scoring system of Roland and Morris, and the rating system of Prolo, Oklund and Butcher. Instability was determined according to the criteria described by White and Panjabi.

A significant decrease in low back pain and disability was seen. An excellent or good outcome was noted in 79% of patients; 9% showed secondary radiological instability.

Surgical decompression is a safe and efficient procedure. In the absence of preoperative radiological evidence of instability, fusion is not required.

The progression of post-tubercular kyphosis in 61 children who received ambulatory chemotherapy was studied prospectively. The angles of deformity and kyphosis were measured for each patient at diagnosis, 3, 6, 9, 12 and 18 months later and every year thereafter for 15 years. During the course of the disease signs of instability appeared on the radiographs of some of the children. These were dislocation of the facets, posterior retropulsion of the diseased fragments, lateral translation of the vertebrae in the anteroposterior view and toppling of the superior vertebra. Each sign was allocated one point to create a spinal instability score. The influence on the progression of the deformity of the level of the lesion, the vertebral body loss, the number of segments involved, the angle of deformity before treatment and the spinal instability score was analysed.

The mean angle of deformity at the start of treatment was 35°. This increased to 41° at 15 years. Progression occurred during the active phase of the disease and again after cure when variations in progression were observed. Type-I progression showed an increase in deformity until growth had ceased. This could occur either continuously (type Ia) or after a lag period of three to five years (type Ib). Type-II progression showed decrease in deformity with growth. This could occur immediately after the active phase (type IIa) or after a lag period of three to five years (type IIb). Type-III progression showed minimal change during either the active or healed phases and was seen only in those with limited disease.

Multiple regression analysis showed that a spinal instability score of more than 2 was a reliable predictor of patients with an increase of more than 30° in deformity and a final deformity of over 60°. Since signs of radiological instability appear early in the disease, they can be reliably used to identify children whose spine is at risk for late progressive collapse. Surgery is advised in these cases.

A total of 39 HIV-infected adults with spinal tuberculosis underwent anterior spinal decompression for neurological deficit. Fresh-frozen allografts were used in 38 patients. Antituberculous drugs were prescribed for 18 months, but antiretroviral therapy was not used. Six patients died within two years of surgery. Neurological recovery and allograft incorporation were observed at follow-up at a mean of 38 months, although the CD4/CD8 ratios were reversed in all patients. Adequate preoperative nutritional support and compliance with antituberculous treatment are essential in ensuring a satisfactory outcome.

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.

Instability may present at a different level after successful stabilisation of an unstable segment in apparently isolated injuries of the cervical spine. It can give rise to progressive deformity or symptoms which require further treatment. We performed one or more operations for unstable cervical spinal injuries on 121 patients over a period of 90 months. Of these, five were identified as having instability due to an initially unrecognised fracture-subluxation at a different level. We present the details of these five patients and discuss the problems associated with their diagnosis and treatment.

It has been suggested that matrix metalloproteinase-3 (MMP-3, stromelysin-1) has an important role in the degeneration of intervertebral discs (IVDs). A human MMP-3 promoter 5A/6A polymorphism was reported to be involved in the regulation of MMP-3 gene expression. We suggest that IVD degeneration is associated with 5A/6A polymorphism.

We studied 54 young and 49 elderly Japanese subjects. Degeneration of the lumbar discs was graded using MRI in the younger group and by radiography in the elderly. 5A/6A polymorphism was determined by polymerase-chain reaction-based assays. We found that the 5A5A and 5A6A genotype in the elderly was associated with a significantly larger number of degenerative IVDs than the 6A6A (p < 0.05), but there was no significant difference in the young. In the elderly, the IVD degenerative scores were also distributed more highly in the 5A5A and 5A6A genotypes (p = 0.0029).

Our findings indicate that the 5A allele is a possible risk factor for the acceleration of degenerative changes in the lumbar disc in the elderly.

Percutaneous nucleotomy is a relatively new technique for treating lumbar disc herniation. There is no agreement as to the volume of disc material to be removed. A long-term study of clinical and radiological data from patients treated by percutaneous nucleotomy was designed to identify the factors associated with favourable and unfavourable outcomes. We studied 42 patients for at least ten years; the mean follow-up was 10.9 years. They were divided into two subgroups to assess the value of preserving the nucleus pulposus in the central area of the disc.

The overall success rate for both subgroups was 50%. A decrease in disc height on plain radiography and a decrease in signal intensity on MRI were observed more infrequently in patients in whom the nucleus pulposus in the central area of the disc had been preserved, than in those in whom it had been extensively removed. These adverse radiological findings correlated closely with increased low back pain during the first one to two years after operation and a poorer overall outcome.

We conclude that percutaneous nucleotomy is most likely to be successful when the central area of the disc is preserved.

Of 586 employed patients with a whiplash injury 40 (7%) did not return to work. The risk was increased by three times in heavy manual workers, two and a half times in patients with prior psychological symptoms and doubled for each increase of grade of disability. The length of time off work doubled in patients with a psychological history and trebled for each increase in grade of disability. The self-employed were half as likely to take time off work, but recovered significantly more slowly than employees.

We present a study of ten consecutive patients who underwent excision of thoracic or thoracolumbar hemivertebrae for either angular deformity in the coronal plane, or both coronal and sagittal deformity. Vertebral excision was carried out anteriorly alone in two patients. Seven patients had undergone previous posterior spinal fusion. Their mean age at surgery was 13.4 years (6 to 19). The mean follow-up was 78.5 months (20 to 180). The results were evaluated by radiological review of the preoperative, postoperative and most recent follow-up films.

The mean preoperative coronal curve was 78.2° (30 to 115) and was corrected to 33.9° (7 to 58) postoperatively, a mean correction of 59%. Preoperative coronal decompensation of 35 mm was improved to 11 mm postoperatively. Seven patients had significant coronal decompensation preoperatively, which was corrected to a physiological range postoperatively. There were no major complications and no neurological damage.

We have shown that resection of thoracic and thoracolumbar hemivertebrae can be performed safely, without undue risk of neurological compromise, in experienced hands.

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.

Craniodiaphyseal dysplasia (CDD) is a rare sclerosing bone disorder, the severity of which depends on its phenotypic expression. Hyperostosis can cause progressive foraminal stenosis leading to palsy of cranial nerves, epilepsy and mental retardation. We report the only case of CDD in an adult, with stenosis of the cervical canal leading to quadriparesis as a late complication of hyperostosis, and describe the problems associated with its treatment. Although the syndrome is rare, its pathophysiological and therapeutic considerations may be applicable to the management of stenosis of the spinal canal in other hyperostotic bone disorders.