Objectives

Degenerative disc disease (DDD) and osteoarthritis (OA) are relatively frequent causes of disability amongst the elderly; they constitute serious socioeconomic costs and significantly impair quality of life. Previous studies to date have found that aggrecan variable number of tandem repeats (VNTR) contributes both to DDD and OA. However, current data are not consistent across studies. The purpose of this study was to evaluate systematically the relationship between aggrecan VNTR, and DDD and/or OA.

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

1. Primary lumbar vertebral instability or "pseudo-spondylolisthesis" varies from about 3 millimetres to 1·7 centimetres, and is perhaps the commonest radiological sign associated with lumbo-sacral pain after the third decade of life. It was observed in 28·6 per cent of 500 consecutive cases of lumbo-sacral pain. The next commonest cause is gross disc degeneration, which is a late result of instability. 2. The secondary instability that may accompany a nuclear prolapse or osteoarthritis is excluded from this discussion. 3. This lumbar instability is an early sign of "incipient disc degeneration," occurring before narrowing of the disc space, sclerosis of the epiphysial rings, or osteophyte formation becomes evident. The instability in the lower lumbar region is caused by incomplete radial posterior tears, usually between the fourth and fifth lumbar vertebrae; and in the upper lumbar region from anterior concentric fissures or slits between some of the lamellae of the annulus fibrosus. 4. As shown radiologically, lumbar instability is commonest between L.4-5 and is rare between L.5 and sacrum because the facets between L.5-S.1 normally face forwards and backwards and thus resist anterior sliding. 5. The usual direction of antero-posterior sliding in the case of the upper four lumbar vertebrae is posterior—that is, the upper vertebra is displaced backwards on the one immediately below it during full extension in the erect position. The displacement tends to disappear on forced flexion, which may cause anterior displacement. On the other hand, the reverse displacement may exist between the fifth lumbar vertebra and the sacrum. 6. Operative treatment by bone grafting is a last resort in carefully selected individuals. After operation the patient rests in bed for three months without rigid splinting. Bone grafting is best for a localised lesion (affecting only one disc); it is generally not advisable if more than two discs are involved. 7. The results in thirty patients treated by spinal fusions showed that 70 per cent had no pain and resumed work, l3·3 per cent had improvement and resumed work, and l6·7 per cent were worse or no better

Aims

We set out to determine if there is a difference in perioperative outcomes between early and delayed surgery in paediatric supracondylar humeral fractures in the absence of vascular compromise through a systematic review and meta-analysis.

Aims

In patients with a rotator cuff tear, tear pattern and tendon involvement are known risk factors for the development of pseudoparalysis of the shoulder. It remains unclear, however, why similar tears often have very different functional consequences. The present study hypothesizes that individual shoulder anatomy, specifically the moment arms (MAs) of the rotator cuff (RC) and the deltoid muscle, as well as their relative recruitment during shoulder abduction, plays a central role in pseudoparalysis.

1. A review of 204 cases of prolapsed intervertebral disc treated by the author by operation ten to twenty-five years before is presented. Injury was an etiological factor in only 14 per cent. 2. The decision to operate should be made after a clearly defined and controlled, but limited, period of closed treatment. The patients should not have to wait for operation. Treatment by closed methods should not be continued in the absence of detectable signs of improvement. Continuation under such circumstances delays recovery from paralysis, prolongs convalescence and delays return to work. Persistence of paraesthesia and numbness are other probable consequences of such delay. 3. A central disc prolapse is an indication for urgent operation if persistent sphincter disturbance or incomplete bladder evacuation is to be avoided. 4. A recurrence rate of sciatica less frequent than that associated with treatment by closed methods is noted in this and other reported series. True recurrence, as opposed to a prolapse at another level, is rare and is most probably due to continuation of the biochemical process of degeneration leading to further sequestration of disc tissue. On the other hand, the altered spinal mechanics, particularly local rigidity resulting from enucleation of a deranged intervertebral disc, may predispose to prolapse at a higher level or may themselves be the cause of symptoms of "recurrence". 5. Operation gives early and lasting relief of sciatic pain, reduces the need for the subsequent use of a corset and assists the patient to an early return to work. 6. Operation does not affect the decision to change work. This is decided by the length of history before operation and the amount of disc degeneration; and the need to change work is the same whether the patient is treated by closed means or by operation. 7. Apart from simple back raising exercises to strengthen the spinal extensor muscles, no physiotherapy need be given because it is not likely to improve the prognosis. 8. Backache is the most frequent disability after operation (17 per cent) and is related to the degree of degenerative change present before and after operation. Injury precipitated the onset of backache in three cases. Operation does not by itself produce backache. The amount of bone removed has no demonstrable effect on the late results of operation, nor on the subsequent development of degenerative changes. 9. Enucleation of the nucleus is not followed by fibrous ankylosis across the intervertebral space

A review of the pathology, mechanism, and operative treatment of recurrent dislocation of the shoulder, based on an analysis of 180 cases, with 159 operations, is presented. From this analysis the following conclusions have been made and appear to be substantiated:. 1. The pathology comprises two important elements: (a) anterior detachment of the glenoid labrum from the bone margin of the glenoid, associated with some degree of stripping of the anterior part of the capsule from the front of the neck of the scapula, found in 87 per cent. of cases examined adequately at operation; (b) defect or flattening of the posterolateral aspect of the articular surface of the head of the humerus which engages with the glenoid cavity when the arm is in external rotation and abduction; this defect is demonstrated most readily in antero-posterior radiographs taken with the humerus in 60 to 70 degrees of internal rotation and was shown to be present in 82 per cent. of cases which had been subjected to adequate radiographic examination. 2. The frequency of the humeral head defect has been under-estimated in the past, because of the difficulty of demonstrating it, particularly when the defect is small. 3. Either type of lesion alone may predispose to recurrence of the dislocation. 4. Both types of lesion are often present in the same shoulder. When this is the case the tendency to redislocation is great. 5. The initial dislocation, which results in the development of one or both these persistent structural abnormalities, may be due to very different types of injury, the commonest of which is a fall on the outstretched hand. The factor common to all these injuries is a resultant force acting on the humeral head in the direction of the anterior glenoid margin. 6. In the treatment of recurrent dislocation of the shoulder joint the Nicola operation is unreliable, and it may be associated with a recurrence rate as high as 36 per cent. It is believed that continued instability after this operation is usually due to the presence of a defect of the humeral head. 7. Operative treatment should aim at repairing, or nullifying, the effects of both types of lesion. For anterior detachment of the labrum this involves either suturing the labrum back to the glenoid margin, or constructing some form of anterior buttress, fibrous or bony: for humeral head defects it necessitates some procedure designed to limit external rotation, thus preventing the defect from coming into engagement with the glenoid cavity. Such limitation of external rotation does not constitute a significant disability

Aims

Loosening is a well-known complication in the fixation of fractures using devices such as locking plates or unilateral fixators. It is believed that high strains in the bone at the bone-screw interface can initiate loosening, which can result in infection, and further loosening. Here, we present a new theory of loosening of implants. The time-dependent response of bone subjected to loads results in interfacial deformations in the bone which accumulate with cyclical loading and thus accentuates loosening.

Aims

To determine whether an early return to sport in professional Australian Rules Football players after fixation of a non-thumb metacarpal fracture was safe and effective.

1. Chondrosarcoma is a malignant tumour of bone with clinical and morphological features which distinguish it from osteosarcoma. 2. Cartilage tumours present an unbroken spectrum in their clinical behaviour and histological appearances from the entirely benign to the frankly malignant. 3. A few chondrosarcomata, particularly those in children and young adults, run a rapidly fatal course but in general they metastasise late and some kill by local extension of the tumour. 4. "Secondary" chondrosarcomata arising from a pre-existing osteocartilaginous exostosis or enchondroma are mostly low grade tumours. 5. The first appearance of an osteocartilaginous exostosis after skeletal maturity, renewed growth, or pain unassociated with a fracture, should arouse suspicion of malignancy in any cartilage tumour. 6. Cartilage tumours of the trunk and upper end of femur and humerus are especially liable to sarcomatous change. 7. Although most benign cartilage tumours occur in the hand and foot they rarely become malignant with the exception of those in the calcaneus. 8. If biopsy is necessary it should be of the incisional type, a generous amount of material being removed from the edge of the tumour. Calcified, degenerate areas must be avoided. 9. In low grade tumours microscopic fields judged to be malignant by Lichtenstein and Jaffe's well established criteria may be scanty and many paraffin sections should be examined. Absence of mitotic figures, heavy calcification and poor vascularity are no guarantee of benignity. 10. Information as to the site of the tumour and age of the patient must be available to the pathologist if a useful report is to be given. 11 . In "borderline" tumours or where any difficulty in diagnosis arises the clinical, radiographic and histological features must all be taken into account and treatment based on the most unfavourable features. 12. Chondrosarcoma is a radio-resistant tumour and treatment is by radical excision or amputation. 13. Malignant cartilage cells implanted in the tissues at operation will often continue to grow and in all instances the biopsy wound and surrounding tissues must be removed en bloc with the tumour. 14. Small, low grade, readily accessible, peripheral tumours may be successfully treated by excision with a wide margin of healthy tissue. 15. In the limbs or pelvis large tumours and those of high grade malignancy should be treated by amputation. Since marrow permeation is often greater than the radiograph suggests amputation should, as a rule, not be performed through the bone in which the chondrosarcoma is situated. 16. Recurrence carries the danger that an initially accessible tumour becomes inaccessible and inoperable and, less frequently, a low grade tumour recurs in a metastasising form. 17. Recurrence is frequent after inadequate surgery; it indicates that the tumour is at least locally malignant and a cure can usually only then be achieved by more radical surgery

Objectives

Metabolic syndrome and low-grade systemic inflammation are associated with knee osteoarthritis (OA), but the relationships between these factors and OA in other synovial joints are unclear. The aim of this study was to determine if a high-fat/high-sucrose (HFS) diet results in OA-like joint damage in the shoulders, knees, and hips of rats after induction of obesity, and to identify potential joint-specific risks for OA-like changes.