I have tried to stimulate interest in movement as a method of treatment. It is too much to expect that I shall have won over to my way of thinking doctors who are addicts of rest. I shall be content if they will occasionally ask: "Is my splint really necessary?"

1. Paraplegia from fracture-dislocation at the thoraco-lumbar junction is a mixed cord and root injury. The root damage can be distinguished from cord damage by neurological examination and by comparison of the neurological level with the fracture level.

2. Even though the cord injury is complete, as it usually is, the roots often escape or recover.

3. Fracture-dislocations can be divided into stable and unstable types. Because of the possibility of root recovery care must be taken to prevent further damage to the roots by manipulation of the spine or during treatment. For this reason unstable fracture-dislocations are fixed internally by plates.

4. Internal fixation also assists in the nursing of the patient. The nursing technique and the care of the bladder are described.

1. Thirty-one cases of tuberculosis of the elbow have been reviewed and the general characters of the disease described.

2. The condition is classified into four types distinguishable radiologically.

3. Treatment is predominantly conservative. Operation is sometimes indicated for extra-articular lesions. Arthrodesis is advisable in selected cases but it is not essential for healing.

4. Of twenty patients observed for five years or more, seventeen returned to work, seven required permanent splintage and five had residual pain or sinuses.

5. It is suggested that the best position for fixation of the elbow is 30 degrees below the right angle.

1. The preparation of heterogenous grafts of calf bone is described.

2. The results of experimental application of such grafts in dogs and guinea pigs are recorded.

3. The results of eighty heterogenous grafts in humans are reported.

4. It is concluded that if the conditions are carefully controlled the results of heterogenous grafting are satisfactory.

Based on the constancy with which the limbus is inverted into the joint in a typical congenital dislocation of the hip, a hypothesis is presented which suggests that the sequence of events leading to established dislocation is: 1) lateral rotation aided and abetted by anteversion; 2) extension of the hips causing subluxation; 3) dislocation and inversion of the limbus; 4) secondary changes in the upper end of the femur, pelvis and acetabulum which will also develop if the deformity does not progress beyond a subluxation.

A pen picture is drawn showing how anteversion is either moulded away during growth to produce a normal hip, or persists with or without dislocation. The fate of the persistently inverted limbus is discussed and a line of treatment based on these findings is briefly considered.

1. Three cases of congenital kyphosis at or near the thoraco-lumbar junction are reported.

2. The features of the deformity are discussed.

Osteoarthritis, as seen in the hip, is a disease which eventually embraces all the tissues of the joint but begins as a reaction of the juxta-chondral blood vessels to a degeneration of the articular cartilage; this reaction results in a hyperaemia of the bone. To our surprise we found that daily use preserves rather than "wears out" articular cartilage; indeed inadequate use is the commonest cause of cartilage degeneration and ensuing vascular invasion. To this factor are added the effects of excessive pressure in the many patients who require surgical treatment for advanced osteoarthritis of a hip the seat of some anatomical incongruity. This etiology based on cartilage suffering does not exclude, but indeed explains, the osteoarthritis implanted on joints of a normal shape which have been previously affected by acute or chronic inflammation or by hormonal dysfunction, such as acromegalic osteoarthritis. The stimulus to vessel growth and invasion is the same in all these cases—namely cartilage damage. Once the vessels have entered the cartilage the bone and marrow of the osteophyte are inevitably laid down. What is so damaging in osteoarthritis seems to be not the degeneration of the cartilage but the vigorous and persistent attempt at repair, an attempt which aggravates the already disordered function of the joint not only by osteophyte formation but by the hypervascularity which weakens the structure of the bone beyond the point where it can carry its increased load. The collapse that follows provokes further reparative efforts with the same deplorable results. The osteoarthritic process thus appears to be an attempt to transform a decaying joint into a youthful one and for this, as in the miraculous rejuvenation depicted in Goethe's Faust, a high price must ultimately be paid.

1. The synovial membrane and capsule in osteoarthritis of the hip have been studied in twenty-five cases. Dissections have been made on fresh cadavers to establish the normal structure and function of these tissues at different ages.

2. Fragments of bone and cartilage were found beneath the synovial surface in twenty-three cases of the twenty-five cases of osteoarthritis.

3. The source of these fragments is the degenerate articular surfaces.

4. The fibrosis of the synovial membrane and capsule follows the synovial hyperplasia which accompanies the phagocytosis of these fragments.

5. A similar histological picture has been produced by injecting fragmented cartilage into the knee joints of rabbits. The injected fragments are found beneath the surface, and synovial hyperplasia is followed by subsynovial fibrosis.

6. The greatest amount of this joint debris is found in the lowest part of the joint cavity.

7. The joint capsule is particularly sensitive to traction.

8. All parts of the capsule are tight in extension, which is the weight-bearing position.

9. Fibrotic shortening of the capsule in the lowest part of the joint cavity explains many of the symptoms and signs of the disease: pain is caused by an attempt to stretch the capsule; muscle spasm occurs in the muscles supplied by the sensory nerves of this part of the capsule; extension, medial rotation and abduction, which tighten this area, are lost first; progressive shortening causes deformity in the opposite direction, namely flexion, lateral rotation and adduction; the loss of extension causes a more rapid wearing of articular cartilage on weight bearing; subperiosteal new bone is formed on the under-surface of the neck of the femur.

10. The symptomatology is discussed.

1. The bone cysts of osteoarthritis are found in relation to defects in the watertight layer between the joint space and the cancellous bone; these defects are sometimes obvious openings, but more often they are openings closed by fibrous tissue, fibrocartilage or new bone. The small cysts lie close to the surface. Their rounded outlines suggest the agency of fluid pressure in their formation, and the fluid and cells found in the cysts are compatible with origin in the joint space and articular cartilage.

2. The hypothesis is advanced that the cysts are formed by the intrusion of synovial fluid under pressure into the substance of the bone, and the sclerosis around by displacement of the trabeculae and their reinforcement by new bone.

3. The objections to the hypothesis that the cysts represent a primary degeneration in the bone are discussed.

1 . The extensor digitorum longus of the rabbit was partly denervated by section of one of its two nerve branches and examined histologically for evidence of sprouting of new fibres.

2. Sections from material fixed two and three days after operation showed terminal bundles in which varying numbers of axons and motor end-plates have degenerated. This supports the concept that the motor unit is not confined to single groups of neighbouring muscle fibres, but innervates fibres scattered throughout the muscle.

3. New fine fibres branching from intact intramuscular axons to reinnervate denervated muscle fibres were observed as early as four days after operation.

4. Such new fibres were most numerous in the early weeks after operation and their numbers then declined. Two months after operation no small fibres or simple end-plates were seen.

5. No new fibres were seen in areas of the muscle containing only denervated nerve fibres. The new fibres were formed only under the stimulus of proximity to the degenerating ones.

6. The relationship of these findings to the mechanism of recovery of human muscle affected by poliomyelitis is discussed.