Full thickness samples of articular cartilage were removed from areas of chondromalacia on the medial and "odd" facets of the patellae of 21 adults and examined by histology, autoradiography and electron microscopy. Surface fibrillation, loss of superficial matrix staining and reduced 35SO4 labelling was seen, with little change in the deep zone. Ten cases showed "fibrous metaplasia" of the superficial cartilage with definite evidence of cell division and apparent smoothing of the surface. Scattered chondrocyte replication appeared to occur in the surrounding intact cartilage. The findings suggest that early lesions in chondromalacia patellae may heal either by cartilage or fibrous metaplasia and that this may account for the resolution of clinical symptoms

We have developed a method of measuring anterior displacement of the calcaneus on the talus in instability of the subtalar joint and have used the technique to demonstrate anterior instability in 50 patients (72 feet) showing a positive drawer sign. The angle of the posterior facet of the talus was also measured to assess the bony configuration. Our patients with subtalar joint instability could be divided into three categories. The first group had a history of trauma leading to ankle instability (26 cases), the second showed generalised joint laxity (10 cases) and the third were young females with a history of chronic stress on the foot and a poor bony block (14 cases). Satisfactory results were obtained by treating the instability with a brace or by reconstruction of the interosseous talocalcaneal ligament

Aims

The purpose was to evaluate early clinical, patient-reported, and radiological outcomes of the scapholunate ligament 360° tenodesis (SL 360) technique for treatment of scapholunate (SL) instability.

Entire human cadaveric cervical spines with the basiocciput were subjected to load in a compression apparatus to simulate the clinical situation of forward dislocation. The movements were recorded by lateral cineradiography. Vertical load was measured by a potentiometric transmitter synchronised with each frame of the cineradiograph. The lower part of the spine was flexed and fixed, and the upper extended and free to move forward. Vertical compression then produced bilateral dislocation of the facets without fracture. If lateral tilt or axial rotation occurred as well, a unilateral dislocation was produced. The maximum vertical load was only 145 kilograms, and coincided with the rupture of the posterior ligament and capsule and the stripping of the anterior longitudinal ligament, but this occurred before dislocation. The low vertical load indicates a peculiar vulnerabiity of the cervical spine in this position and correlates well with the minor trauma often seen in association with forward dislocation

Spondylolisthesis without a defect in the neural arch, the "pseudo-spondylolisthesis" of Junghanns, usually affects the fourth lumbar vertebra. The essential lesion is an increase in the angle between tile inferior facets and the pedicles which allows subluxation at the inferior joints. The forward displacement averages less than one centimetre. It commonly produces a clinical picture of backache and sciatica, but may present with. a "drop foot," and in unusual instances compression of the cauda euluina may occur. Patients seen in the early stages without signs of nerve root compression are best treated by localised spinal fusion. Late fusion may afford no relief because of secondary changes in the spine, but these patients obtain some benefit from a corset. Laminectomy is indicated for severe symptoms in patients who show signs of nerve root compression; it should be followed by spinal fusion

Six normal cadaver lower limbs were mounted on a specially designed loading apparatus. Wires were used to simulate the five muscle bellies of the quadriceps, the ratio of their tensions having been determined from that of the anatomical cross-sectional areas of the muscles. A three-camera system was used to track the patella during knee movements from flexion to extension. The patellofemoral contact area was determined by pressure-sensitive film. The limb was loaded with and without tension on the wire which simulated the oblique part of the vastus medialis (VMO). Absence of VMO tension caused the patella to displace laterally (4.2 mm) and increased the load on the lateral patellar facet throughout the range of knee motion. When the tension on the wire simulating vastus lateralis was reduced by 40% to simulate the effect of a lateral release procedure, the abnormal kinematics caused by the absent VMO returned to normal

Over a nine-year period, 20 feet with persistently symptomatic talocalcaneal coalition were treated by resection of the bar. The 17 patients were all under 16 years of age. Excellent or good long-term results were achieved in the ten feet in which preoperative coronal CT had shown that the area of coalition measured 50% or less of the area of the posterior facet of the calcaneum. In these feet heel valgus was less than 16 degrees and there were no radiographic signs of arthritis of the posterior talocalcaneal joint. Talar beaking was present in 70% of these feet but it did not impair the clinical result. Fair or poor results were observed in the ten feet in which preoperative CT had shown the area of relative coalition to be greater than 50%. In these feet, heel valgus was greater than 16 degrees and most had narrowing of the posterior talocalcaneal joint and impingement of the lateral process of the talus on the calcaneum

The thalamus is the part of the calcaneus that supports the posterior articular facet and continues forward, becoming thinner towards the groove of the sinus tarsi. The main displacements after fracture depend on 1) a primary fracture line dividing the bone into anterior and posterior fragments, and 2) a semilunar fragment in the thalamic region. In the operation advised the sinus tarsi is exposed and the semilunar fragment is reduced by rotation in the opposite direction and is fixed to the medial fragment (the sustenaculum tali not being displaced) by a transverse Kirschner wire. The two main fragments are fixed by an antero-posterior wire. Plaster is applied and is retained for twelve weeks. Weight-bearing is not permitted for the first four weeks. There were no major complications in fifty-eight operations. The anatomical results were good: restoration of the tuber-joint angle by reduction of the semilunar fragment was maintained. The functional results were very satisfactory: permanent disability was slight or mild

We performed a case-control study on the influence of oophorectomy on the development of degenerative spondylolisthesis, including a clinical review and determination of serum oestradiol levels. We also compared the radiological appearance of the lumbar spine at L4/5 in patients with and without spondylolisthesis and with and without oophorectomy. Oophorectomy was a risk factor for degenerative spondylolisthesis with an odds ratio of 7.5 (95% confidence interval, 1.6 to 46). The incidence of degenerative spondylolisthesis in 69 oophorectomised patients was about three times higher than in 69 non-oophorectomised matched control subjects. There was also a difference in spinal variation between oophorectomised and non-oophorectomised patients with spondylolisthesis. A high incidence of sagittal-plane orientation of the L4/5 facet and an increase in pedicle-facet angle were seen in both groups and are typical radiological features of this disease. An increase in lumbosacral angle and in disc-space narrowing was seen only in the non-oophorectomised patients with this condition. Our results suggest that the abrupt decrease in oestradiol level caused by oophorectomy may be a predisposing factor in degenerative spondylolisthesis at L4/5

Aims

The aim of this retrospective study was to compare the correction achieved using a convex pedicle screw technique and a low implant density achieved using periapical concave-sided screws and a high implant density. We hypothesized that there would be no difference in outcome between the two techniques.

Aims

Femoroacetabular impingement (FAI) describes abnormal bony contact of the proximal femur against the acetabulum. The term was first coined in 1999; however what is often overlooked is that descriptions of the morphology have existed in the literature for centuries. The aim of this paper is to delineate its origins and provide further clarity on FAI to shape future research.

Aims

Restarting planned surgery during the COVID-19 pandemic is a clinical and societal priority, but it is unknown whether it can be done safely and include high-risk or complex cases. We developed a Surgical Prioritization and Allocation Guide (SPAG). Here, we validate its effectiveness and safety in COVID-free sites.

Low lumbar pain with radiation into the leg is a common symptom pattern caused by a number of pathological processes. Isolated disc resorption is one such entity which can be readily identified and is amenable to surgical treatment. This study consisted of two groups of patients. Group I were 50 patients suffering from isolated disc resorption at L5--S1 with ill-defined low backache extending into the buttocks and down one or both legs, but not into the feet. Clinical signs of nerve root dysfunction were found in 16 per cent of patients. Radiographic changes with loss of disc height, facet over-riding and intrusion into the nerve root canal and intervertebral foramen were common and frequently associated with sclerosis of the vertebral end-plate. Group II were a series of 45 patients with isolated disc resorption independently reviewed an average of 45 months after surgical decompression of the S1 (98 per cent) or lower lumbar nerve roots. Based on objective grading by the clinician and subjective assessment by the patient complete success was achieved in 62 per cent of the patients and partial success in 24 per cent. Provided there is full appreciation of the pathological anatomy, strict diagnostic criteria and meticulous surgery, decompression of the nerve root canal is a useful surgical procedure in severely disabled patients suffering from isolated disc resorption

MRI studies of the knee were performed at intervals between full extension and 120° of flexion in six cadavers and also non-weight-bearing and weight-bearing in five volunteers. At each interval sagittal images were obtained through both compartments on which the position of the femoral condyle, identified by the centre of its posterior circular surface which is termed the flexion facet centre (FFC), and the point of closest approximation between the femoral and tibial subchondral plates, the contact point (CP), were identified relative to the posterior tibial cortex. The movements of the CP and FFC were essentially the same in the three groups but in all three the medial differed from the lateral compartment and the movement of the FFC differed from that of the CP. Medially from 30° to 120° the FFC and CP coincided and did not move anteroposteriorly. From 30° to 0° the anteroposterior position of the FFC remained unchanged but the CP moved forwards by about 15 mm. Laterally, the FFC and the CP moved backwards together by about 15 mm from 20° to 120°. From 20° to full extension both the FFC and CP moved forwards, but the latter moved more than the former. The differences between the movements of the FFC and the CP could be explained by the sagittal shapes of the bones, especially anteriorly. The term ‘roll-back’ can be applied to solid bodies, e.g. the condyles, but not to areas. The lateral femoral condyle does roll-back with flexion but the medial does not, i.e. the femur rotates externally around a medial centre. By contrast, both the medial and lateral contact points move back, roughly in parallel, from 0° to 120° but they cannot ‘roll’. Femoral roll-back with flexion, usually imagined as backward rolling of both condyles, does not occur

One of the interesting aspects of spinal pathology having an important bearing on the treatment of backache is that the spine acts as an integrated whole and that damage sustained by one part frequently injures other structures in the spinal column. Thus disc degeneration may be associated with an extrusion of nuclear material; it may initiate degenerative changes in the posterior joints; it may predispose to tears of the posterior spinal ligaments; or it may give rise eventually to all of these lesions, any one of which may produce backache with or without sciatica. The sciatica may be referred pain or may be produced by nerve root pressure. Nerve root pressure in such instances is commonly due to an extrusion of nuclear material, but it may also be due to pressure on the nerve root within the foramen by a "squashed" disc or by a subluxated posterior joint. Radiographs are of great value in the diagnosis of disc degeneration and they are of greater value in the assessment of the secondary effects that have taken place. With the use of bending films evidence of early degenerative changes may be obtained, tears of the supraspinous ligament can be detected, and abnormal movements of the posterior joints can be seen. Careful study of the antero-posterior and lateral projections will reveal evidence of subluxation of the posterior joints, chip fractures and degenerative arthritis in the zygapophysial articulations, and will clearly demonstrate overriding of the facets. The investigation of subjective phenomena, such as backache, is fraught with many difficulties and it must be preceded by an investigation of the anatomy of the part and the anatomical variations, the normal and abnormal physiology and the pathological lesions that occur. Many of these changes of course may have no clinical significance, but it is only when armed with the knowledge of what may occur that we can tackle the problem of low back pain on a logical basis

Aims

To report mid- to long-term results of Oxford mobile bearing domed lateral unicompartmental knee arthroplasty (UKA), and determine the effect of potential contraindications on outcome.