1. An analytical study of eighty histologically proven cases of Paget's sarcoma confirms and elaborates existing knowledge of the etiology of this tumour. The frequency with which this tumour occurs in certain parts of England may be seen by comparison with the numbers of osteosarcoma and fibrosarcoma cases registered at Bristol and Leeds. An overall incidence figure for Paget's sarcoma of 0·l6 and 0·18 per 100,000 population per annum has been calculated for the Bristol and Leeds areas respectively. The similarity of the age incidence curves of Paget's disease and Paget's sarcoma are shown and discussed in the light of demographic information.

2. Histologically, most Paget's sarcomata resemble recognised tumour types as seen in otherwise normal bones, the most frequent forms being osteosarcoma and fibrosarcoma. The type of tumour arising in an osteitic bone is uninfluenced by age, sex or site of origin. Thirty-eight per cent of the cases were complicated by fracture, which occurred with slightly greater frequency in fibrosarcoma and with advancing age. A causal connection between sarcoma and fracture is supported but not vice versa.

3. Survival statisticsfor this series are compared with Bristol records for osteosarcoma and fibrosarcoma (without Paget's disease), the mean survival of seventy-four patients being 11·1 months from the date of the initial symptoms of malignancy. Four long-term survivors are reported, the five-year and ten-year survival rates being respectively 5 per cent and 3·1 per cent. The effects of age, site, sex, fracture and treatment upon survival are tabulated and discussed.

1. A series of 154 patients who underwent anterior cervical discectomy and fusion has been studied. A detailed analysis of the first eighty-four patients who have been observed for periods of from one to eight and a half years is described. In sixty-eight patients the fusion was done with a keystone type of graft, in seventeen by a dowel (Cloward) graft.

2. Despite a preponderance of multiple level fusions in the keystone series, clinically better results (80·8 per cent excellent or good) were found in this group than in the dowel group (64·8 per cent excellent or good).

3. A biomechanical study has indicated the keystone graft to be more stable than a dowel graft under flexion and extension strains as well as lateral bending strain. The graft is more stable the closer it is to the line of "zero velocity."

4. The three cases of non-union all occurred in the dowel group. The high incidence of fusion with the keystone technique is considered to be related to the type of graft, its method of seating, its depth of penetration, its larger surface area and the fact that raw cancellous bone of the adjacent vertebral bodies is in contact with the graft above and below.

1. Paralytic dislocation of the hip in spina bifida generally requires reduction and iliopsoas transfer. The muscle transfer ensures that the hip remains reduced, lessens the need for calipers and prevents progressive flexion deformity. In addition, varus and rotation osteotomy of the femur and innominate osteotomy are sometimes required. Varus and rotation osteotomy alone is indicated if the psoas is not strong enough for transfer. The age for reduction of dislocated hips and muscle transfer has been reduced to eight months as experience and confidence has been gained.

2. Flexion deformity is best prevented by early iliopsoas transfer. An anterior release operation is occasionally indicated when there is flexion deformity and a weak psoas muscle. This procedure, alone or supplemented by extension osteotomy, may be necessary to correct severe flexion deformity in children seen late.

3. Lateral rotation deformity of the hip may be caused by unbalanced iliopsoas action or the unbalanced action, or contracture, of the short lateral rotator muscles. If the deformity is sufficient to make the gait bizarre, or if it is difficult to fit a caliper, then soft-tissue operations as described are of value.

4. Abduction deformity can be corrected by division of the unopposed or contracted abductors.

This series, albeit consecutive and unselected, is very small; conclusions must therefore be tentative. The results do however suggest that the dangers of late manipulative reduction properly performed may have been exaggerated. Attempted without undue force it proved a harmless procedure, often successful even in cases of long duration. When it succeeds, the results in slips of unacceptable degree are at least as good as those following the more major surgical procedures, which can thus be avoided. Even when the displacement is minor its correction should on theoretical grounds at least decrease the prospects of later osteoarthritis. The only absolute contra-indication is a fused epiphysial plate. The degree of slip and above all the duration of symptoms should not preclude an attempt at manipulative reduction.

1. We have considered torsional deformity in club feet and conclude that medial torsion does not occur in the tibia.

2. It is suggested that in uncorrected feet the hindfoot with the ankle mortise is laterally rotated.

3. We have discussed the cause, prevention and consequences of spurious correction by lateral rotation.

4. The "bean-shaped foot" seems an appropriate description of the final deformity as it is commonly seen.

1. Bony spurs resulting from erosion of the scaphoid bone and trapezium in rheumatoid arthritis can pierce the floor of the carpal tunnel and cause attrition rupture of flexor tendons–most often the flexor pollicis longus tendon.

2. It is difficult to show these spurs on conventional radiographs, but using a special tomographic technique we have been able to explore the floor of the carpal tunnel in three planes. Using this technique we have been able to guard the flexor pollicis longus against attrition rupture by early excision of a spur from the scaphoid bone.

3. Our findings support the recommendation of free division of the flexor retinaculum in rheumatoid arthritis. When doing this the surgeon should always look for a bony spur piercing the floor of the carpal tunnel.

It has been known for well over a century that the corresponding ossification centres of the hand tend to appear before those of the foot (Mall 1906), although even now the range of variability remains poorly defined. Presumably a similar asynchrony also obtains for chondrification, although precise timing is more difficult here than for ossification. Accordingly, it is tempting with respect to this syndrome to relate fusions restricted to the phalanges of the hand and to the tarsal bones to the action of a gene which during a very limited period of development exerts an effect on those small bones of the hand and foot which are in a very specific stage of development. But since there are other inherited abnormalities of the skeleton, such as brachydactyly, where homologous bones are involved, it is clear that at the descriptive level gene action can either appear to be "stage-specific" or "homologue-specific." There are also mutations affecting the axial skeleton such as the type of polydactyly of the foot described by Neel and Rusk (1963) which appear to be neither "stage" nor "homologue" specific, involving only the foot. Finally then, there are syndromes, such as Lawrence-Moon-Biedl-Bardot, in which involvement of the hands and feet (polydactyly) is associated with such other apparently completely unrelated defects as retinitis pigmentosa and hypogonadism. While it is tempting to try to construct theoretical patterns and systems of developmental processes on the basis of results such as these, it is clear that the ultimate understanding of how genes can appear to act in so many ways almost certainly depends on the identification of a genetically controlled, qualitative or quantitative biochemical lesion. With the current parallel developments in biochemical and developmental genetics, new insights into these enigmas will surely be forthcoming in the relatively near future.

1. The patient, who at the age of ten and a half years was described by Jánsen as the first recorded case of metaphysial dysostosis, has been re-examined at the age of forty-four and the clinical, pathological and radiological findings at various ages have been compared. Measurements have been compared with those obtaining in normal individuals.

2. The striking feature is the development of normal bony structure associated with marked deformity and dwarfing. Joint surfaces have remained intact.

3. There is some deafness, which is partly caused by sclerosis of the petrous temporal bone.

1. Monostotic fibrous dysplasia in the long bones occurs most frequently in adolescence. In the jaws it is found mainly in early adult life. It presents later in the ribs, probably because it is often asymptomatic in this site.

2. The disease is equally distributed in both sexes.

3. Reactivation may occasionally occur in later life and in pregnancy.

4. Successful surgical treatment is by no means always easily achieved, and requires, in addition to the problems of fracture fixation and the correction of deformity, careful consideration of the age of the patient, the activity of the lesion and the extent to which it involves the cortical bone.

1. A patient is described, the thirty-fourth reported, who shows all the skeletal changes of pycnodysostosis with the exception of the oral findings.

2. It is suggested that the pseudarthroses of the tibiae in our patient cannot be taken as evidence against normal union because of the possibility of inadequate management of the fractures.

3. We consider that the use of strong intramedullary nails in the treatment of long bone fractures in these cases is advisable.

1. A series of 154 patients with 156 femoral shaft fractures treated during a three and a half year period is reviewed. Fifty-four fractures were treated by closed intramedullary nailing, sixty-four by open intramedullary nailing and thirty-eight by conservative methods.

2. All the patients had fresh fractures of a similar degree of severity. Seventy-eight per cent of the fractures were sustained in traffic accidents, and 21 per cent were compound.

3. The technique of closed intramedullary nailing is described in detail. The importance of a complete and faultless armamentarium and a high-quality image intensifier is emphasised.

4. All fractures united within twelve months after the accident.

5. The functional results were assessed upon the basis of walking ability and return to work. Nailed fractures did better than conservatively treated ones, and closed nailing was slightly superior to open nailing. At twelve months after the injury all patients treated by closed nailing walked without a stick, compared with 96 per cent of the cases treated by open nailing and 81 per cent of the conservatively treated patients. The same trend was noted regarding return to work.

6. The benefit of intramedullary nailing was partly dependent on the severity of the fracture and the age of the patient. The most gratifying results of nailing were obtained in patients over thirty-five years of age with severe fractures.

7. Osteitis occurred in one case treated by closed nailing, and low grade wound infections in five cases, representing an overall infection rate of 3·8 per cent.

8. Seventy-four per cent of the patients were examined one to four years after the fracture. There was less angular deformity and more rotational deformity in the nailed than in the conservatively treated fractures. The tip of the nail gave slight discomfort in the trochanteric area in one patient in three. Residual joint stiffness was infrequent in the nailed cases as compared to the conservatively treated ones.

9. The indications for closed intramedullary nailing of femoral shaft fractures are outlined.

1. Forty-four cases of Smith's type fractures are reviewed and emphasis laid upon the significance of the different fracture types.

2. Treatment is reviewed and recommendations made for future management.

1. Attention is drawn to lesions of the inferior tibio-fibular ligaments. Two main types are described: the anterior type and the total type.

2. The clinical and radiological characteristics are described.

3. The value of strain-view radiography is stressed.

4. A plan of treatment is suggested.

1. In this analysis of forty-three patients with syringomyelia, twenty-seven (63 per cent) had scoliosis. This association is probably due to the early involvement of the ventro-medial and dorso-medial nuclei of the spinal cord by expanding lesions.

2. The literature makes no reference to the treatment of scoliosis associated with syringomyelia. Two cases are presented of attempts to correct this scoliosis–one because of increasing deformity, the other for increasing backache.

3. Due to the presence of cystic lesions characteristic of syringomyelia, corrective operative treatment of scoliosis may present an added risk.

4. Because of the high incidence of scoliosis in patients with syringomyelia, any patient with scoliosis should be examined for evidence of neurological deficit.

1. A woman of seventy-four presenting with gigantism of the left hand and foot, lipomatosis, progressive arthropathy and psoriasis is described.

2. The associations of the various conditions are examined in the light of the previously reported cases and the differential diagnosis of this condition (macrodystrophia lipomatosa) from other causes of localised gigantism is discussed.

Two cases of post-traumatic avascular necrosis of the head of the femur without evident dislocation of the head or fracture of the head or neck are recorded.

1. Arrest of growth at one proximal tibial epiphysis of young rabbits was obtained by stapling.

2. Radiopaque markers allowed the subsequent growth of both proximal and distal epiphyses of the experimental and contralateral tibiae and of both lower femoral epiphyses to be followed radiographically.

3. The reduction in the normal deceleration of growth rate at the distal epiphysis found after epiphysiodesis of the proximal epiphysis was again observed.

4. This change in growth rate was not encountered in the distal femoral epiphysis lying adjacent to the stapled tibial epiphysis.

5. Removal of the staples after the change in growth rate had become established at the distal tibial epiphysis was followed by a return to an approximately normal growth rate by both proximal and distal epiphyses.

6. It is concluded that a direct relationship exists between the additional growth at the uninjured epiphysis and the deficiency in growth obtained at the stapled epiphysis, and that this change in growth rate is limited to the experimental tibia.

1. Specimens are described in which osteoid was seen in undecalcified bone sections prepared from a number of osteoarthritic femoral heads.

2. It was localised mostly in the pressure segments.

3. The reason for the presence of this osteoid is not well understood and the possibilities of local histochemical changes and/or cellular metaplasia are discussed.

1. A method is described for the in vivo and in vitro study of osteogenesis by implanting a modified transparent chamber in half lop-eared rabbits (as originated by Sandison 1928). This method allows the daily observation and photography of the developing bone and the study of its intimate connection with the vascularity of the area.

2. The osteogenetic potential of a variety of substances can also be investigated by this method. The tissue in the chamber can easily be prepared for its final examination by optical and electron microscopy and by other laboratory techniques.