1. The capsular changes in osteoarthritis of the hip and their pathogenesis are described, and it is concluded that symptoms are due mainly to this abnormality.

2. The clinical significance and pathogenesis of subchondral sclerosis, cysts, osteophytes, secondary subluxation and new bone formation on the lower border of the femoral neck are discussed.

3. These bony features which can be seen in the radiograph may, under certain circumstances, be correlated with the symptoms.

4. The influence of joint debris and capsular fibrosis upon the symptoms arising in other osteoarthritic joints is considered.

5. The mechanism by which osteoarthritis develops in hip joints with an anatomical abnormality is discussed in relation to the normal functional anatomy of the hip.

6. The evolution of osteoarthritis in dysplasia of the hip is considered with special reference to its diagnosis, prognosis and early treatment.

7. The supposition that osteoarthritis is commonly due to progressive ischaemia in the femoral head has been investigated and is rejected.

8. The cause of idiopathic osteoarthritis remains obscure but the evidence suggests that constitutional rather than local conditions in the joint account for many of these cases.

1. A detailed analysis of the anatomy of spondylolisthesis reveals many causes of serious interference with the nerve roots.

2. These anatomical findings can be correlated with the symptoms.

3. In association with spondylolisthesis, cases of disc prolapse, tuberculosis, and a cauda equina lesion are described.

4. Adequate decompression of the affected nerve root is essential in all cases with sciatica. The operative procedure is described.

5. The problem of arthrodesis will be discussed fully in a separate paper.

1. The results of a three-year study of recovery in 3,033 lower limb muscles and 1,905 upper limb muscles in 142 patients are presented.

2. The rate of recovery of partly paralysed muscles is the same in all muscles and muscle groups in the lower or upper limb. Clinical differences in the ability of individual muscles to recover depend upon the proportions of their number that remain permanently paralysed.

3. The rate of recovery is slowest in adults and most rapid in young children.

4. The amount of further recovery to be expected in a muscle can be predicted from a knowledge of its grade at any time after one month from the onset of the paralysis. Fourteen-fifteenths of the total amount of recovery takes place by the beginning of the twelfth month; with rare exceptions individual muscle recovery is complete after twenty-four months.

5. Ninety per cent of muscles that are still completely paralysed after six months remain permanently paralysed.

6. The prognosis of a completely paralysed muscle is related to the level of paralysis in muscles supplied by the same spinal segments.

7. Deterioration in power in a muscle is uncommon and, when it occurs, is associated with the presence of the strong opposing force of antagonist muscles or of gravity.

8. The application of these findings to the management of cases of paralytic acute anterior poliomyelitis is discussed.

1. Details are given of sixty-three consecutive cases with a history of pleural effusion seen at an orthopaedic hospital.

2. Twenty-four of these were post-primary effusions occurring before the onset of symptoms of the orthopaedic lesion. The bone and joint lesions ultimately developing in this group of patients were widely scattered throughout the skeleton.

3. Three others were secondary to adult-type pulmonary lesions.

4. Thirty-six patients had a pleural effusion after the beginning of their orthopaedic tuberculous history. Seven were certainly secondary to operative intervention, six in the thorax near the parietal pleura (costotransversectomy or antero-lateral decompression of the cord) and one from a haematogenous dissemination after fusion of a hip joint.

5. The remainder of this group with pleural effusion during the history of their orthopaedic tuberculous disease numbered twenty-nine. Of these, twenty-five suffered from disease of the thoracic spine; in two more details are defective. Only two definitely had neither pulmonary nor thoracic spinal disease; their lesions were in the lumbar spine.

The conclusion is drawn that the overwhelmingly common cause of pleural effusion in patients with orthopaedic tuberculosis who have normal lungs and have not recently suffered spinal decompression is transpleural infection from thoracic spinal disease and that the sequence is by no means rare. It had occurred in approximately one in six of 145 patients with thoracic Pott's disease seen during this investigation.

6. Details are given of a group of cases with thoracic paravertebral abscess tracking laterally. When the abscess is well clear of the spine and spinal ligaments it may project forwards and radiologically it may appear in the antero-posterior chest film as a shadow in the middle of one or other lung field rather than as a shadow obviously connected with the central paravertebral abscess. Aspiration will yield pus from this posterior extra-pleural abscess extension.

7. The belief that Pott's disease most commonly follows direct spread from caseous paraaortic glands secondary to tuberculous pleurisy is discussed. It is concluded that the evidence is insufficient for so sweeping a statement.

"Wedge excision" of the apex of the curve is the rational way of correcting a scoliosis. It is a straightforward procedure which is successful in practice.

1. The previous literature in English on tuberculosis of the subdeltoid bursa is reviewed.

2. Two further cases are reported.

3. Emphasis is placed on the neglect of the condition in standard text-books and the need for bearing the diagnosis in mind.

4. Treatment by radical excision, a period of immobilisation and full supportive antibiotic therapy are recommended.

1. A simple and effective method of wrist arthrodesis is described. Originally designed for the correction of flexion deformity of the wrist, it is useful also as a routine method of wrist fusion.

2. The results in nineteen cases are reviewed.

Three cases of osteochondritis dissecans of the knee in two brothers and a sister are described. In the brothers both knees were involved. None of the other joints of the skeleton was affected in any of the patients.

Osteochondritis dissecans occurring bilaterally in either the knees or the elbows is recorded in four members of one family. The suggestion is supported that the underlying pathology may be developmental, resulting in a form of localised osteochondrodystrophy.

Radiopaque solutions and suspensions introduced into cancellous bone in the extremities of the cadaver are rapidly removed into the venous system through regional superficial or deep veins. The experiments described in this communication confirm the simplicity of methods of introduction of fluids into cancellous bone and justify further observations on their clinical application for the technique of phiebography.