1. A twenty-six-year-old woman was paraplegic because of a benign giant-cell tumour which had destroyed the body of the twelfth thoracic vertebra completely and the bodies of the eleventh thoracic and first lumbar vertebrae partially. The tumour had expanded into both pleural cavities and displaced the aorta forward and to the left. The extent and topography of the tumour were evaluated before operation by angiography. The function of the spinal cord had not been improved significantly by laminectomy. It was therefore decided to attempt extirpation of the tumour by removing all remaining parts of the three vertebrae involved. 2. After the removal of the tumour, only the spinal cord with the thecal sac bridged the gap between the tenth thoracic and second lumbar vertebrae. The gap was bridged with struts of cortical bone from both tibiae and with two strong plates, all secured with steel wire. The metal was removed five months later because it had become loose. Gradual shortening and angulation of the spine then occurred, together with progressive resorption of the cortical grafts. Nevertheless, the operation restored the function of the spinal cord; the patient regained ability to walk and full control of the bladder

1 . Young Wistar rats fed on a diet containing 0·3 per cent semicarbazide hydrochloride developed the characteristic lesions of osteolathyrism. This consisted of kyphoscoliosis, displacement of epiphyses and dislocations of joints. A pathological study of the skeletal lesions showed widening, disorganisation and tears of the epiphysial plate with the zone of maturing cartilage showing the greatest increase in width. The severe kyphoscoliosis was due to a derangement and displacement at and through the epiphysial plates of the twelfth thoracic or first lumbar vertebra. 2. Some of the compounds that are known to produce osteolathyrism in laboratory animals are beta aminopropionitrile, amino acetonitrile, mercaptoethylamine and semicarbazide. The mode of action of the lathyrogenic compounds was analysed in the light of a number of experiments done in this laboratory. 3. lt is possible that they interfere with the metabolism of the epiphysial plate. There appears to be a decreased polymerisation of the ground substance of the epiphysial cartilage, but the exact metabolic reaction involved is not known. Other chemicals of similar structure, with the same reactive groups, did not show lathyrogenic properties. It is concluded that it is not a particular chemical structure, configuration or specific reactive group that is responsible for the production of osteolathyrism. The chemistry of the lesions still remains to be solved

The principle of Occam's razor proves nothing. Nevertheless, it is possible to explain all the phenomena of severe scoliosis on the basis of a primary rotation deformity alone. The typical rotation type of scoliotic deformity can be reproduced artificially by fitting vertebrae together in an abnormal rotatory relationship without any element of lateral flexion. From this, certain mechanical factors inevitably come into play which must tend to increase the deformity. Above all, the forces responsible for progressive scoliosis are dynamic and active, not just passive. The spine readily compensates for a passive, non-progressive deformity such as a simple wedge vertebra. It is my belief that rotation is usually the dominant factor and that correction and control of severe scoliosis can only be achieved by concentrating on the rotation deformity. I am well aware that this is an old idea but its essential truth has been insufficiently appreciated in recent years and we have not faced its full implications. Failure to correct rotation invites recurrence. Conversely, even a slight reduction in rotation usually produces a marked cosmetic improvement, often out of all proportion to the radiographic appearances

Vertebroplasty, which is the percutaneous injection of bone cement into vertebral bodies has recently been used to treat painful osteoporotic compression fractures. Early clinical results have been encouraging, but very little is known about the consequences of augmentation with cement for the adjacent, non-augmented level. We therefore measured the overall failure, strength and structural stiffness of paired osteoporotic two-vertebra functional spine units (FSUs). One FSU of each pair was augmented with polymethyl-methacrylate bone cement in the caudal vertebra, while the other served as an untreated control. Compared with the controls, the ultimate failure load for FSUs treated by injection of cement was lower. The geometric mean treated/untreated ratio of failure load was 0.81, with 95% confidence limits from 0.70 to 0.92, (p < 0.01). There was no significant difference in overall FSU stiffness. For treated FSUs, there was a trend towards lower failure loads with increased filling with cement (r. 2. = 0.262, p = 0.13). The current practice of maximum filling with cement to restore the stiffness and strength of a vertebral body may provoke fractures in adjacent, non-augmented vertebrae. Further investigation is required to determine an optimal protocol for augmentation

We have used an experimental model employing the bent tail of rats to investigate the effects of mechanical forces on bones and joints. Mechanical strain could be applied to the bones and joints of the tail without direct surgical exposure or the application of pins and wires. The intervertebral disc showed stretched annular lamellae on the convex side, while the annulus fibrosus on the concave side was pinched between the inner corners of the vertebral epiphysis. In young rats with an active growth plate, a transverse fissure appeared at the level of the hypertrophic cell layer or the primary metaphyseal trabecular zone. Metaphyseal and epiphyseal trabeculae on the compressed side were thicker and more dense than those of the distracted part of the vertebra. In growing animals, morphometric analysis of hemiepiphyseal and hemimetaphyseal areas, and the corresponding trabecular bone density, showed significant differences between the compressed and distracted sides. No differences were observed in adult rats. We found no significant differences in osteoclast number between compressed and distracted sides in either age group. Our results provide quantitative evidence of the working of ‘Wolff’s law’. The differences in trabecular density are examples of remodelling by osteoclasts and osteoblasts; our finding of no significant difference in osteoclast numbers between the hemiepiphyses in the experimental and control groups suggests that the response of living bone to altered strain is mediated by osteoblasts

1. The results of wide laminectomy of the fifth lumbar vertebra and disc excision in 132 patients are reviewed and compared with some published results of the interlaminar operation. 2. There was no significant difference in either the immediate or the long-term results of the two operations suggesting that post-operative morbidity was not related to operative technique. 3. The incidence of post-operative back pain was found to increase with age at operation, duration of pre-operative symptoms and length of follow-up, and supported the impression that backache is predominantly a feature of the underlying degenerative process rather than the incidental operation. 4. The significance of recurrent disc lesions is discussed. Recurrence usually occurred at the previously cleared disc space and was thought to indicate incomplete degeneration of the disc at the time of the original operation. 5. The place of fusion combined with disc excision is discussed. No reliable indications for coincident fusion were found in this series. 6. The value of radiography is discussed. Plain radiographs were essential before operation to exclude other causes of backache and sciatica; otherwise they were of little value. Motion radiographs were no more helpful and myelography was used only when the level of the lesion was in doubt. 7. The risk of an acute cauda equina lesion following manipulation of a prolapsed lumbar disc is noted and the danger of manipulation, unless facilities for emergency surgery are available, is stressed

Aims

High-grade dysplastic spondylolisthesis is a disabling disorder for which many different operative techniques have been described. The aim of this study is to evaluate Scoliosis Research Society 22-item (SRS-22r) scores, global balance, and regional spino-pelvic alignment from two to 25 years after surgery for high-grade dysplastic spondylolisthesis using an all-posterior partial reduction, transfixation technique.

Aims

The aim of the present study was to answer the question whether curve morphology and location have an influence on rigid conservative treatment in patients with adolescent idiopathic scoliosis (AIS).

A radiographic suvey has been carried out of 147 first-degree relatives of forty-seven patients treated in Edinburgh for spondylolisthesis of the fifth lumbar vertebra; twelve patients had the dysplastic (congenital) type and thirty-five an isthmic defect. The survey identified 19 per cent of relatives with spondylolysis, and index patients with each type of spondylolisthesis had relatives with the opposite type. Index patients with the dysplastic form had a higher proportion of affected relatives (33 per cent) than had those with the isthmic type (15 per cent), but both figures were significantly in excess of the estimated frequency for the general population of under 1 per cent and 5 per cent respectively. Spina bifida occulta at the fifth lumbar or first sacral level or both, and lumbosacral segmental defects were commoner amongst all individuals with spondylolysis than amongst unaffected relatives (dysplastic form 94 per cent, isthmic type 32 per cent, unaffected relatives 7 per cent). However, there was no single instance of a neural tube defect (anencephaly, spina bifida with or without meningocele, other generalised vertebral anomalies or spinal dysraphism) amongst 826 first-, second- or third-degree relatives. It is concluded that the developmental defects of the vertebrae associated with spondylolysis are not aetiologically related to the neural tube defects. The one in three risk of spondylolysis to near relatives of patients with the dysplastic form of spondylolisthesis is emphasised in order that the deformity in their sibs and children can be recognised at any early age

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

Aims

It is uncertain whether instrumented spinal fixation in nonambulatory children with neuromuscular scoliosis should finish at L5 or be extended to the pelvis. Pelvic fixation has been shown to be associated with up to 30% complication rates, but is regarded by some as the standard for correction of deformity in these conditions. The incidence of failure when comparing the most caudal level of instrumentation, either L5 or the pelvis, using all-pedicle screw instrumentation has not previously been reported. In this retrospective study, we compared nonambulatory patients undergoing surgery at two centres: one that routinely instrumented to L5 and the other to the pelvis.

Aims

The complex relationship between acetabular component position and spinopelvic mobility in patients following total hip arthroplasty (THA) renders it difficult to optimize acetabular component positioning. Mobility of the normal lumbar spine during postural changes results in alterations in pelvic tilt (PT) to maintain the sagittal balance in each posture and, as a consequence, markedly changes the functional component anteversion (FCA). This study aimed to investigate the in vivo association of lumbar degenerative disc disease (DDD) with the PT angle and with FCA during postural changes in THA patients.

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).

Aims

Morphological abnormalities are present in patients with developmental dysplasia of the hip (DDH). We studied and compared the pelvic anatomy and morphology between the affected hemipelvis with the unaffected side in patients with unilateral Crowe type IV DDH using 3D imaging and analysis.

Aims

Patients with abnormal spinopelvic mobility are at increased risk for instability. Measuring the change in sacral slope (ΔSS) can help determine spinopelvic mobility preoperatively. Sacral slope (SS) should decrease at least 10° to demonstrate adequate posterior pelvic tilt. There is potential for different ΔSS measurements in the same patient based on sitting posture. The purpose of this study was to determine the effect of sitting posture on the ΔSS in patients undergoing total hip arthroplasty (THA).

Aims

Sickle cell disease (SCD) is an autosomal recessive inherited condition that presents with a number of clinical manifestations that include musculoskeletal manifestations (MM). MM may present differently in different individuals and settings and the predictors are not well known. Herein, we aimed at determining the predictors of MM in patients with SCD at the University Teaching Hospital, Lusaka, Zambia.