1. Experimental radiological and mechanical studies on a cadaveric cervical spine are reported.

2. A series of fifty-nine dislocations and fracture-dislocations of the cervical spine is reviewed.

3. The methods of reduction and indications for operation are discussed.

1. Evidence is presented that certain types of cervical spine injury are due mainly to lateral flexion forces.

2. These injuries are often complicated by a brachial plexus lesion as well as a lesion of the spinal cord.

3. It is not always easy to detect the brachial plexus injury when the patient is first seen.

4. In the cases reviewed there has been little or no recovery of cord function, and the existence of a brachial plexus injury has, of course, made rehabilitation much more difficult.

5. The practical importance of recognising the mechanism of this type of injury is that treatment which will cause further separation of the vertebrae is inadvisable.

1. During a fifteen-year period a clinical, radiological and in some cases a surgical study has been made of 319 patients suffering from spondylolisthesis–that is, forward slipping of one lumbar vertebra on another or forward sagging of the whole lumbar spine in relation to the sacrum.

2. The five etiological factors are described, and the cases are assigned to five groups according to the factor responsible for the slip. In every case slipping is permitted by a lesion of the apparatus which normally resists the forward thrust of the lower lumbar spine–that is, the hook of the neural arch composed of the pedicle, the pars interarticularis and the inferior articular facet engaging caudally over the superior articular facet of the vertebra below.

3. In Group I (congenital spondylolisthesis–sixty-six cases) the lesion is a congenital defect of the facets. In Group II (spondylolytic spondylolisthesis–164 cases) the lesion occurs in the region of the pars interarticularis and is either an elongation of the bone or a break in continuity. There are reasons for thinking that the lesion is caused by stress over a long period rather than by acute injury or by a congenital anomaly of ossification. In Group IV (degenerative spondylolisthesis–eighty cases) the lesion of the facets is degenerative. There are no good grounds for thinking that an abnormality of the angle between the facets and the pedicles is the primary lesion behind the degenerative change.

4. Group III and V comprise few cases. In the former (traumatic spondylolisthesis–three cases) the lesion–a fracture of the neural arch–is caused by a single severe injury. In Group V (pathological spondylolisthesis–six cases) the slipping is caused by weakness of bone from various causes.

5. A full description is given of the etiological and biomechanical features of each group. A special investigation has been made into the etiological factors in degenerative spondylolisthesis.

6. The incidence of involvement of nerve tissues is highest in degenerative spondylolisthesis; the most severe degrees of slip are found in congenital spondylolisthesis.

1. Musculoplastic stump correction is a method of physiological preparation of all the elements of the stump–muscles, bone, vessels and nerves–so as to establish the best relations between them. It removes the cause of existing circulatory disorders by creating active muscular movements.

2. In all cases stump pains, even those of causalgic character, have been eliminated. We attribute this to the attainment of normal muscular tension, and we believe that many phantom sensations and pains are caused by cramped and retracted muscles.

3. Active muscular work produces increased arterial inflow, as has been shown by arteriography, and also eliminates venous stasis in the end of the stump by restoration of the muscle pump mechanism.

4. Stumps prepared in the way described become painless and warm and their muscles become strong.

1. In a club foot the small inverted and elevated heel is considered to be the most important deforming influence in preventing complete correction and in promoting relapse.

2. Correction of the varus and an increase in the vertical height of the heel are achieved by opening up the medial aspect of the calcaneum and inserting a wedge of bone. This abolishes the inverting action of the calcaneal tendon and brings the heel down on to the ground directly under the line of the tibia so that it touches first in walking. The weight is then shifted on to the forefoot, as in the normal gait, thus producing gradual correction of supination and adduction.

3. The operation may have to be repeated, but with the varus fully corrected and a plantigrade heel there is no chance of relapse, and progressive improvement, not only in gait and shoe wear but also in the development of the foot and leg, can be expected.

4. Skin closure is a difficulty, and though the resulting scar is sometimes conspicuous, it is masked to some extent by being on the postero-medial aspect of the ankle.

5. The ideal age for the operation is about three to four years, but there is virtually no upper age limit.

6. In older patients presenting severe residual deformity it may be necessary to correct the heel and then the equinus of the forefoot by a tarso-metatarsal wedge, thus avoiding damage to the mid-tarsal and subtalar joints.

7. By adopting these principles, soft-tissue release operations, so often disappointing and sometimes damaging, can be avoided and in no patient should there ever be the need to resort to the mutilating "triple wedge" resection.

8. The most important feature of the operation is correction of the varus; it is better to over-correct than to under-correct (Figs. 20 and 21). It is a simple matter to deal with the valgus later if necessary.

1. Ectopic ossification is commonest in, but not confined to, traumatic paraplegia. It occurs also in many other neurological disorders which have in common a gross disturbance of spinal cord reflex activity. It is a true ossification and must be distinguished from calcification.

2. The neurological lesion may lie anywhere from the cerebral cortex to the mixed peripheral nerve. It may involve motor tracts, sensory tracts or a mixture of both.

3. The ossification is localised and self-limiting. It occurs mainly in the lower limbs and is restricted to certain muscles or muscle groups, the nerve supply of which is always below the level of the central neurological lesion.

4. The blood chemistry is usually normal.

5. A true arthropathy is rare except as part of a secondary suppurative arthritis.

6. The resemblance to myositis ossificans progressiva or to ossifying haematoma is only superficial, although the pathological process at cellular level may be the same.

7. The period of onset after paraplegia is variable. The earliest recorded example is in one of our own cases in which ossification occurred nineteen days after injury. Other patients have developed ossification after several years.

8. The condition is commonest in acquired nervous disease rather than in congenital disorders, and so far as we know it has not been described in the myopathies. The presence of muscular spasticity or flaccidity is relevant only in that it indicates a disturbance of reflex activity.

9. Soft-tissue ulceration appears to be frequently associated with ectopic ossification. The type of new bone formation associated with large chronic ulcers is not to be compared with the new bone formation in the muscles of a paraplegic patient in otherwise good general condition.

10. The occurrence of urinary tract infections with calculi and generalised sepsis is not specifically related to the onset of new bone formation.

11. Localised soft-tissue oedema often precedes the formation of new bone. Its appearance is undoubtedly important, but the mechanism of its origin is obscure.

12. It is not yet known what initiates ectopic ossification, what limits its spread and what finally causes it to stop.

13. We have described 100 examples of ectopic ossification in 603 paraplegic patients.

14. Surgery has been required in only eight patients. The only indication for surgery is bony ankylosis of the hip in an unacceptable position.

1. The technique of arthrography in congenital displacement of the hip is described. No complications have been encountered in a series of over 200 examinations. The interpretation of the arthrographs is discussed.

2. It is suggested that the abnormal hips may be classified in three degrees: 1) Primary instability; 2) partial displacement without interposition of soft tissue; 3) complete displacement with interposition of soft tissue between head and socket.

3. Two types of complete displacement or dislocation are recognised: 1) the "tight" dislocation; 2) the "loose" dislocation. In the latter there is marked displacement of the femoral head, and arthrography done before reduction demonstrates interposition of a fold of capsule lying in front of the inverted limbus.

4. Arthrography is of special help in making the diagnosis between partial displacement with eversion of the labrum and "tight" dislocation with an interposed limbus. It is helpful too in establishing the cause of failure of reduction.

1. The results of rehabilitation of 181 patients with fractures of the shaft of the femur are analysed

2. The results are mainly dependent on the severity of the fracture and the method of reduction and immobilisation. It is stressed that full-time rehabilitation can help to attain the best results.

3. The advantages of intramedullary nailing of fractures of the femoral shaft are discussed.

1. A review of intra-articular and peri-articular fractures of the phalanges has been carried out, and the late results of such injuries have been examined.

2. These fractures usually unite by bone.

3. The results of conservative treatment by immobilisation are satisfactory in the case of mallet fractures, hyperextension sprain fractures and collateral avulsion fractures of the proximal phalanges.

4. The less satisfactory results after collateral avulsion fractures of the interphalangeal joints and avulsion fractures complicating dislocations are discussed.

Of fifteen patients treated by excision of the lunate bone and prosthetic replacement twelve had no pain at all or slight discomfort after exceptionally heavy work. All these were able to return to and continue at heavy manual jobs. Two patients continued to experience pain with vigorous use of the wrist but were none the less satisfied with their improvement. In one patient the operation failed and pain persisted unrelieved.

We believe that the radiographs show that the prosthesis greatly minimises the distortion of the carpus after excision of the lunate bone and that the maintenance of a normal carpal architecture is important in the avoidance of osteoarthritis of the remaining joints. The results suggest that when the operation is technically successful degenerative changes do not occur despite prolonged and heavy use. The presence of osteoarthritis in the wrist before operation is not a contra-indication to prosthetic replacement because the degenerative process may remain stationary for several years after removal of the damaged lunate bone.

The prosthesis has proved durable over many years and none of our patients having attained a good wrist has suffered a relapse. The operation entails a month off work for a heavy labourer and as little as a fortnight for those who do lighter jobs. These considerations prompt us to suggest its wider use in the treatment of Kienböck's disease.

1. A group of cases is presented in which the os intermetatarseum took the form of an intermetatarsal spur, from which (in members of one family) there arose a tendon-like structure whose distal attachment was to the lateral aspect of the proximal phalanx of the great toe. The suggestion is made that this may represent a lost first plantar interosseous muscle.

2. Another effect of the presence of an os intermetatarseum is the production of metatarsus primus varus by its action as a wedge which spreads apart the bases of the two metatarsal bones. A very small wedge may at times produce considerable deviation (Case 4), and resection of the os can result in satisfactory correction.

3. It is also felt that over-development of extensor hallucis brevis may at times contribute to the formation of hallux valgus.

1. Frostbite in a child may be severe enough to destroy the cartilage cells of the epiphysial plate of a digit, and produce clinical deformity.

2. Both the direct effect of the freezing itself and the vascular changes secondary to such frostbite appear to cause necrosis of the growing epiphysis with destruction of the epiphysis and disappearance of the epiphysial line or plate. The disappearance of the epiphysial plate is obvious, but whether the epiphysis itself is actually destroyed and disappears or simply fuses with the metaphysis is a question now being studied.

3. It is suggested that the deformities may be helped by interphalangeal fusion of severely involved joints in the position of function, and phalanges that become angled into varus or valgus may be improved by open wedge osteotomy or epiphysiodesis of the side of the epiphysis still functioning.

Retrosternal dislocation of the clavicle is an uncommon yet easily induced injury which may cause grave disability. Manipulation is rarely successful and usually open reduction with stabilisation of the joint is required. The literature on this subject is reviewed and an additional two cases are reported.

1. Two patients with retrosternal dislocation of the clavicle are reported.

2. A method of closed reduction is described.

3. Diagnosis, and the interpretation of oblique radiographs of the sternoclavicular joint, are described.

1. A case of traumatic aneurysm of the anterior tibial artery complicating fracture of the tibia and fibula is reported.

2. The diagnosis and management of such lesions are discussed.

1. The changes resulting from superficial scarification of articular cartilage have been observed in the knee joint of adult rabbits. A reduction in the amount of stainable matrix ground substance occurred at the sites of damage. Particular attention was therefore paid to sulphated mucopolysaccharide synthesis by cartilage cells in or near the traumatised areas.

2. The femoral groove cartilage one week after scarification showed evidence of increased mucopolysaccharide synthesis, especially by the more superficial chondrocytes near the cuts, but three or four weeks later the enhanced chondrocyte activity tended to diminish, and after six weeks the superficial cells near the cuts were found to be inactive. From six to thirty-four weeks the loss of stainable ground substance extended more deeply, but cell degeneration in these deeper areas of matrix depletion was preceded by a period in which many of the deeper chondrocytes still showed evidence of active mucopolysaccharide synthesis. Cellular activity in tags of depleted cartilage was usually lost before the tags finally disintegrated. Chondrocyte clusters were often seen in the scarified areas, especially in the deeper zones. They seemed to be a reactive rather than degenerative phenomenon.

3. In the scarified cartilages of the patella examined after one week a reactive response by superficial chondrocytes was less evident than in the femoral cartilage from the same joint, and after six weeks areas of deeply extending matrix loss were exceptional.

4. The structural and functional changes in the rabbits' femoral articular cartilage after its scarification resembled those which have been observed in the developing cartilage lesion of human osteoarthritis–namely, loss of interstitial matrix and superficial fibrillation, a stimulated synthesis of chondroitin sulphate by the chondrocytes, and the appearance of cell clusters in the deeper zones. Within the period of the experiment, up to thirty-four weeks, the joint lesions remained strictly localised to the traumatised areas ofcartilage, and exposure of bone and joint remodelling, which are features of advanced osteoarthritis in man, were not seen.

1. The effect of implanting heterogenous anorganic bone, homogenous organic bone, autogenous compact bone from the iliac crest, and autogenous bony callus into circumscribed defects in the femur of albino rats of the Wistar strain is described.

2. Neither heterogenous anorganic bone nor homogenous organic bone appeared to induce new bone formation in a healing defect.

3. Some of the osteogenic cells of autogenous callus implants survived transplantation to a bone defect and gave rise to new bone formation. This did not occur when compact bone from autogenous iliac crest was implanted.

4. Implants of autogenous callus, autogenous compact bone, homogenous organic bone and heterogenous anorganic bone all impeded the normal development of host bone trabeculae in a healing bone defect, seemingly because they acted as physical barriers to the proliferating host callus. None of the implant materials appeared to suppress the healing reaction ofthe host.

5. Implanted homogenous organic bone was removed and replaced by host bone more quickly than was implanted heterogenous anorganic bone, and it appears to be the better material for grafting into bone defects.

6. Autogenous callus or autogenous cancellous bone is a superior implant material to autogenous compact bone and is the bone graft material of choice.

7. The absorption of all the implant materials used in this investigation was associated with the presence of multinucleated giant cells.

8. The activity of multinucleated giant cells may be influenced by the organic matrix of the material which is to be absorbed.

9. Except when fresh autogenous callus was implanted into the defects, the rate of healing in the grafted defects was slower than that in the control defects. In the defects grafted with fresh autogenous callus the healing rates of the control and grafted defects were the same.

The nutrient foramina in seventy-one adult humeri were examined. The foramina were most concentrated in a small area on the medial aspect of the distal half of the middle third of the shaft. Non-union commonly occurs in this same region. The site of the entrance of the nutrient artery to the humerus is predictable with fair reliability. Certain practical applications have been indicated.

Comparison was made between the behaviour of fresh autogenous grafts of rabbit tendon and that of homogenous grafts inserted after the graft had been preserved for approximately one week, either in ethanol or merthiolate or by lyophilisation.

Regardless of the method of transplantation or preservation, a viable tendon-like structure of compact connective tissue bundles longitudinally oriented was eventually present at the sites of the grafts, with ingrowth of fibroblasts and capillaries from host to graft. The period between transplantation and recognisable viability of the grafts varied from less than one week for the autogenous transplants, to from three to five weeks for the preserved grafts.

Either autogenous or homogenous grafts will take in rabbits.