Aims

The use of vitamin E-infused highly crosslinked polyethylene (HXLPE) in total knee prostheses is controversial. In this paper we have compared the clinical and radiological results between conventional polyethylene and vitamin E-infused HXLPE inserts in total knee arthroplasty (TKA).

1. A study has been made of the blood supply of the human patella. There are two main systems, one penetrating the middle third of the anterior surface and the other entering the lower pole of the bone behind the patellar ligament. 2. The relationship between these findings and the complication of avascular necrosis of the upper fragment of the patella after fracture is discussed. Forty-one cases of necrosis after operation have been studied and notes made on the pathological, clinical and radiological evolution of the condition. Whatever the severity of the ischaemic necrosis the prognosis was not substantially affected and good function was observed in all knees six months after injury. 3. The surgical implications of the vascular anatomy are discussed. It is pointed out that surgical intervention may damage the blood vessels entering the anterior surface of the bone and that circumferential repair of patellar fractures may strangle the vessels in their peripatellar course. 4. If removal of one-half of the patella after a transverse fracture is indicated, vascular studies indicate that the upper fragment should be removed

1. In young rabbits the muscle belly of the tibialis anterior was marked at intervals, either on its surface with indian ink, or in its substance by wires. The intervals between ink marks were measured directly, and those between wires by radiography. After four to seven months the measurements were repeated and the amount and site of longitudinal growth determined. The experiments showed that it occurred fairly evenly throughout the length of the muscle belly. 2. By transfer of the tibialis anterior in front of the crural ligament in young rabbits its course was reduced and the extent of contraction necessary to dorsiflex the foot was increased. The rabbits were killed when fully grown and the lengths of the tendons and muscle bellies of the tibialis anterior of the normal and experimental legs were compared. It was found that in every case the tendon of the experimental muscle was shortened and its belly lengthened in comparison with the normal. It is suggested that the increased length of the muscle belly was determined by the increased distance which it had to contract in order to dorsiflex the foot

Fractures of the scaphoid are most common in young men; immobilisation in a cast usually means a long period away from work and athletic activities. Early rigid fixation has been shown to promote a rapid functional recovery, but open reduction and internal fixation is technically demanding with the dangers of damage to the radiocarpal ligaments, the scaphotrapezial joint, and the blood supply of the scaphoid. For minimally displaced or undisplaced B1 or B2 fractures, these problems can be overcome by percutaneous fixation. We report our technique and the results of a pilot study in 15 patients. There was no immobilisation; patients were allowed movement soon after operation, but union was obtained in all at a mean of 57 days (38 to 71). The range of movement after union was equal to that of the contralateral limb and grip strength was 98% of the contralateral side at three months. Patients were able to return to sedentary work within four days and to manual work within five weeks. Our initial results show that percutaneous scaphoid fixation for acute fractures is satisfactory and gives rapid functional recovery

Objectives

Tranexamic acid (TXA) is an anti-fibrinolytic medication commonly used to reduce perioperative bleeding. Increasingly, topical administration as an intra-articular injection or perioperative wash is being administered during surgery. Adult soft tissues have a poor regenerative capacity and therefore damage to these tissues can be harmful to the patient. This study investigated the effects of TXA on human periarticular tissues and primary cell cultures using clinically relevant concentrations.

We reviewed 32 ankles in 30 patients at an average of five years after a Watson-Jones tenodesis. All but one patient had had ankle pain before operation and 19 had had clicking, catching, or locking of the ankle. Eleven of these had an ankle arthrotomy at the time of ligament reconstruction for intraarticular pathology. At review seven of 23 ankles had a significant decrease in ankle motion, and five in subtalar motion, but only two were unstable on examination. Twenty-one ankles, however, caused some pain on activity and nine were tender on palpation. These findings indicate intra-articular degeneration or injury rather than simple instability. Radiographs of 16 ankles showed good varus and anterior-drawer stability. Seven had talocrural osteoarthritis, but only four showed grade-1 subtalar osteoarthritis. We found no correlation between follow-up time and long-term results. The Watson-Jones tenodesis provides good rotational and lateral ankle instability and does not appear to lead to subtalar degeneration

Ten patients who suffered iatrogenic injury to a vertebral artery during anterior cervical decompression were reviewed to assess the mechanisms of injury, their operative management, and the subsequent outcome. All had been undergoing a partial vertebral body resection for spondylitic radiculopathy or myelopathy (4), tumour (2), ossification of the posterior longitudinal ligament (1), nonunion of a fracture (2), or osteomyelitis (1). The use of an air drill had been responsible for most injuries. The final control of haemorrhage had been by tamponade (3), direct exposure and electrocoagulation (1), transosseous suture (2), open suture (1), or open placement of a haemostatic clip (3). Five patients had postoperative neurological deficits, but most of them resolved. We found direct arterial exposure and control to be safe, quick and reliable. Careful use of the air drill, particularly in pathologically weakened bone, as in infection or tumour, is essential. Arterial injury is best avoided by a thorough knowledge of the anatomical relationships of the artery, the spinal canal, and the vertebral body

Diurnal changes in the loads acting on the spine affect the water content and height of the intervertebral discs. We have reviewed the effects of these changes on spinal mechanics, and their possible clinical significance. Cadaveric lumbar spines subjected to periods of creep loading show a disc height change similar to the physiological change. As a result intervertebral discs bulge more, become stiffer in compression and more flexible in bending. Disc tissue becomes more elastic as its water content falls, and its affinity for water increases. Disc prolapse becomes more difficult. The neural arch and associated ligaments resist an increasing proportion of the compressive and bending stresses acting on the spine. Observations on living people show that these changes are not fully compensated for by modified muscle activity. We conclude that different spinal structures are more heavily loaded at different times of the day. Therefore, the time of onset of symptoms and signs, and any diurnal variation in their severity, may help us understand more about the pathophysiology of low back pain and sciatica

An experimental model of osteoarthritis resulting from laxity of the joint was induced in eighteen mature dogs (at least two years old) by sectioning the anterior cruciate ligament of the right knee (stifle) with a stab incision, the left knee providing a control. A sham operation was also performed in three other dogs, in which a stab incision was made but the ligament left intact. The dogs were killed at various intervals from one to forty-eight weeks later. Morphological changes in bone, cartilage, synovial membrane and joint capsule were examined in all the joints and biochemical changes in the cartilage of three dogs killed after two, eight, and sixteen weeks. All the changes resulting from the operation progressed with time and became indistinguishable from those found in three dogs with natural osteoarthritis of the knee. There were no changes in the joints which had sham operations. As the time of onset is known, this experimental model in a larger species enables a study to be made of the biochemical as well as the morphological changes in the early stages of osteoarthritis

1. Ten consecutive fractures of the dome of the talus are reported. Six were lateral, three medial and one anterior. 2. The injury is most commonly seen in the second and third decades of life, and with the exception of the rare anterior dome fracture, results from an inversion injury of the ankle. The possibility of a dome fracture associated with strain of the lateral ligament of the ankle joint should therefore always be borne in mind. 3. Antero-posterior views in neutral and in plantar fiexion are helpful in diagnosing medial dome fractures. Lateral fractures are best seen in an antero-posterior view taken in neutral flexion with 10 degrees inward rotation of the limb. 4. A large dome fracture with displacement should be accurately reduced by open operation in order to preserve congruity of the joint surface. 5. A small fracture with no displacement may be treated conservatively until radiographically it appears united. 6. A small fracture with marked displacement is best treated by early excision of the fragment to prevent further damage to the ankle joint

1. An investigation was made of the tolerance of the cells in the femoral head in rabbits for ischaemia brought about by transecting the ligament of the femoral head and applying a ligature around the femoral neck. The animals were killed two, six, twelve, twenty-four and seventy-two hours after operation. 2. In the cells of the bone marrow and in the osteoblasts distinct histological signs of disintegration were present six hours after operation. Pyknosis of the osteocyte nuclei was found after twenty-four hours' ischaemia; sometimes vacuolar clarifications could be observed in these pyknotic nuclei. After three days of ischaemia the staining affinity for Feulgen and haematoxylin of a number of osteocyte nuclei had visibly decreased. 3. The Feulgen-DNA content of the osteocyte nuclei-as measured in individual nuclei by means of an integrated microdensitometer-was significantly reduced as compared with similar nuclei from the control side as early as after six hours of ischaemia. This DNA loss was progressive with the period of ischaemia. From these facts, the conclusion was reached that in the femoral head of the rabbit the period of reversible damage for osteocytes must have ended within six hours

1. By the use of a device that allows movement of a human finger joint to take place uninfluenced by muscle activity, the coefficient of friction has been determined between living articular surfaces. 2. The force of friction rises as the range of movement is increased, because of the tension then developing in the ligaments and the soft tissues surrounding the joint. 3. Measurements have also been made of the forces of friction within the ankle joint of the dog and within four types of reciprocating bearings (plastic, oil-lubricated, "floating" and hydrostatic). 4. By altering the load borne by the joints and bearings it has been shown that joints resemble in their behaviour those bearings in which a film of fluid is maintained between the fixed and moving surfaces, rather than bearings depending wholly or in part on boundary lubrication. 5. It is suggested that joints normally owe their great freedom of movement to a special type of fluid film lubrication that has been termed "weeping lubrication," supplemented by "floating lubrication," though on occasions boundary conditions may prevail

Of 111 primary ankle ligament arthroplasties (modified Evans procedure) performed between 1983 and 1994, we were able to identify 89 patients (94 ankles) for follow-up. All were under 50 years of age. Two had died and one refused to co-operate; 86 patients (91 ankles) were therefore reviewed, 25 by telephone and the remainder by clinical examination with all but three also undergoing radiological review. Of the 91 ankles, 70 had no or very mild pain and 72 had no or rare episodes of instability and when considered together only 59 (65%) had no or mild pain and minimal instability. The results were supported by the Karlsson grading system. Clinical examination showed that 17 of the 66 ankles examined had increased inversion, while 21 had some limitation of inversion. Early degenerative changes were seen in 11 ankles, although only four had subtalar changes. These results show that this procedure does not give universally good clinical results. Patient satisfaction, however, was high with 97.7% being willing to undergo the same procedure if their other ankle became similarly affected

We have followed for 13 years a consecutive series of 31 patients who had open repair of a torn meniscus. They were between 13 and 43 years of age at the time of operation and all had intact stabilising ligaments. Comparison was made with a matched group of normal subjects of similar age and level of activity. The total rate of failure after meniscal repair was 29%; three of the repaired menisci did not heal and six reruptured during the follow-up period. At follow-up 80% of the patients had normal knee function for daily activities. Radiological changes were found in seven. Two had reduction of the joint space (Ahlbäck grade 1), one with successful and one with failed repair. In the control group of uninjured subjects one knee showed Fairbank changes but none had changes according to Ahlbäck. The incidence of radiological changes did not differ between the group with meniscal repair and the control group but knee function was reduced after meniscal repair (p < 0.001). We conclude that the long-term results of meniscal repair in stable knees are good with nearly normal function and a low incidence of low-grade radiological changes

The healing of a hamstring graft to bone is the weak link in the reconstruction of a cruciate ligament using this donor material. We therefore investigated the augmentation of healing at the tendon-bone interface using calcium-phosphate cement (CPC). We performed semitendinosus autograft reconstructions of the anterior cruciate ligament on both knees of 22 New Zealand white rabbits. The interface between the grafted tendon and the bone tunnel for one knee was filled with CPC. Six rabbits were killed at the end of the first and second post-operative weeks in order to evaluate the biomechanical changes. Two rabbits were then killed sequentially at the end of weeks 1, 3, 6, 12 and 24 after operation and tissue removed for serial histological observation. Histological examination showed that the use of CPC produced early, diffuse and massive bone ingrowth. By contrast, in the non-CPC group of rabbits only a thin layer of new bone was seen. Mechanical pull-out testing at one week showed that the mean maximal tensile strength was 6.505 ± 1.333 N for the CPC group and 2.048 ± 0.950 N for the non-CPC group. At two weeks the values were 11.491 ± 2.865 N and 5.452 ± 3.955 N, respectively. Our findings indicate that CPC is a potentially promising material in clinical practice as regards its ability to reinforce the fixation of the tendon attachment to bone and to augment the overall effectiveness of tendon healing to bone

We reviewed 50 capitellocondylar elbow replacements performed by the lateral approach in 42 rheumatoid patients, at a median follow-up of three years. There were two major and 17 minor complications; 18 were early and one was late. Eight elbows required reoperation: soft-tissue surgery was performed in seven and prosthesis removal in one because of a deep infection. There were few problems of instability, but one patient sustained a traumatic dislocation which was stabilised after ligament reconstruction. Wound healing was delayed in two of five elbows which had been immobilised postoperatively for only five days, but healing was rapid in 45 elbows immobilised for 12 days. There was transient ulnar-nerve palsy postoperatively in 11 patients, with permanent palsy in three. All elbows were painfree or only slightly painful at follow-up; 49 were stable and 43 had a range of motion sufficient for activities of daily living. Radiological loosening of the humeral component was suspected in one asymptomatic elbow. The lateral approach is recommended for use with the capitellocondylar type of prosthesis in rheumatoid elbows with reasonably well-preserved bone stock

We have treated 45 patients (47 ankles) for chronic lateral instability by a new reconstructive procedure. The operation includes lateral shift of the entire lateral capsule-ligament complex and proximal advancement of the talocalcaneal ligament and the inferior extensor retinaculum. We reviewed 39 patients (39 ankles) at a mean of 4.6 years (2 to 7) after operation. There were 29 men and 10 women with an average age of 27 years (19 to 43); 11 of them were competitive college-level athletes and 28 were recreational athletes. The functional rating was excellent in 26 patients, good in 8, fair in 3 and poor in 2. Thirty-six patients (92%) were satisfied with the result and 34 (9 of 11 college-level athletes and 25 of 28 recreational athletes) have been able to return to their preinjury level of sport. At the last review, there had been only three episodes of recurrent ankle instability, all in recreational athletes; none had required further surgery. The unsatisfactory results were associated with pre-existing degenerative changes in the ankle

Aims

We hypothesized that there is no difference in the clinical and radiological outcomes using local bone graft versus iliac graft for subtalar distraction arthrodesis in patients with calcaneal malunion. In addition, using local bone graft negates the donor site morbidity.

We measured joint position sense in the knee by a new method which tests the proprioceptive contribution of the joint capsule and ligaments. The leg was supported on a splint, and held in several positions of flexion. The subjects' perception of the position was recorded on a visual analogue model and compared with the actual angle of flexion. Eighty-one normal and 45 osteoarthritic knees were examined, as were 10 knees with semi-constrained and 11 with hinged joint replacements. All were assessed with and without an elastic bandage around the knee. There was a steady decline in joint position sense with age in subjects with normal knees. Those with osteoarthritic knees had impaired joint position sense at all ages (p less than 0.001). Knee replacement improved the joint position sense slightly (p less than 0.02); semi-constrained replacement had a greater effect than hinged replacement. The effect of an elastic bandage in subjects with poor position sense was dramatic, improving accuracy by 40% (p less than 0.001). It is proposed that reduced proprioception in elderly and osteoarthritic subjects may be responsible for initiation or advancement of degeneration of the knee

We reviewed the outcome of 422 primary cemented Kinemax total knee arthroplasties implanted into 369 patients over a period of five years, from January 1989. The operations were carried out at two NHS district general hospitals and one teaching hospital by 31 surgeons. During the period of review, 49 patients died and ten knees were lost to follow-up (68 knees). The mean Knee Society score improved from 28 before to 89 after surgery, and the mean function score increased from 23 to 79. The range of flexion improved from 92° to 105°. These improvements were maintained throughout the period of study. At the latest review radiolucent lines of 1 mm were seen around 15% of tibial components, 1.4% of patellar components and 9.5% of femoral components. In no case were these changes progressive. Using revision as the endpoint, cumulative survival was 99% after five years and 96.95% after nine years. All revisions were undertaken for deep infection or secondary trauma. Our study has shown that the Kinemax total knee replacement, when carried out with retention of the posterior cruciate ligament by surgeons of varying experience, produces very satisfactory results in the medium term