1. The case is described of an eight-year-old girl with the Morquio syndrome (mucopolysaccharidosis type IV) who died from acute tetraplegia, due to atlanto-axial subluxation which occurred during general anaesthesia. 2. Hypoplasia of the dens of the axis vertebra entails a high risk of vertebral dislocation and spinal cord damage especially in circumstances such as general anaesthesia when excessive movements of the head may occur

An electromyographic investigation of patients with subluxation of the patella has been carried out on the parts of the extensor apparatus which actively contribute to the alignment of the patella, both before and after the operation to correct this disorder. The electromyographic pictures have revealed a sharp fall in the activity of the vastus medialis, with full recovery to normal values after a corrective operation. Even if the aligning function of the patella is altered by a variety of factors, the present study confirms the importance of the vastus medialis in the pathogenesis of malalignment of the extensor mechanism

We reviewed 25 children who presented consecutively with voluntary (habitual) subluxation of the shoulder. Thirty-six shoulders were involved and symptoms had been present for an average period of 12 years. Eighteen children were managed by 'skillful neglect': all these had become fully active in the profession of their choice and were satisfied with the outcome. Two of them had required shoulder surgery in adult life but only after trauma. Seven children (ten shoulders) had undergone stabilising operations during childhood with the aim of preventing later degenerative arthritis. These patients were also active in their selected professions, but only three (five of the ten shoulders) had good results: two shoulders had recurrent instability, two were painful and one was stiff. None of the shoulders in either group had developed osteoarthritic changes. There was no association with emotional or psychiatric problems. We conclude that voluntary subluxation of the shoulder in children has a favourable prognosis and that there is no indication for surgical intervention during childhood

We have examined whether the rotatory subluxation of the scaphoid which is seen in patients with advanced Kienböck’s disease is associated with scapholunate advanced collapse (SLAC) wrist. We studied 16 patients (11 men, 5 women) who had stage-IV Kienböck’s disease with chronic subluxation of the scaphoid. All had received conservative treatment. The mean period of affection with Kienböck’s disease was 30 years (14 to 49). No wrist had SLAC. In eight patients, 24 years or more after the onset of the disease, the articular surface of the radius had been remodelled by the subluxed scaphoid with maintenance of the joint space. The wrists of six patients were considered to be excellent, nine good, and one fair according to the clinical criteria of Dornan. Our findings have shown that rotatory subluxation of the scaphoid in Kienböck’s disease is not a cause of SLAC wrist and therefore that scaphotrapezio-trapezoid arthrodesis is not required for the management of these patients

1. Eight patients are described in whom the patellae subluxated laterally on every extension of the knee. This is an unusual type of recurrent subluxation. It may recover completely, or remain symptom-free for many years, or increase in severity so that the patient seeks treatment for relief of pain and joint effusion, or progress to frank dislocation. 2. Each patient was examined and the probable causes were analysed. The bayonet deformity was present in twelve of the sixteen knees. A new observation is made on the relationship of tibial crest and tubercle in this condition

In 1957 Somerville and Scott described their "direct approach" to the management of established congenital dislocation of the hip; arthrography after a period of traction served to distinguish the dislocated from the subluxated hip. We review the long-term outcome of hips which, using their criteria, were subluxated; 72 hips have been reviewed at periods ranging from 15 to 37 years after treatment by traction, closed reduction and femoral osteotomy. The results have been classified clinically and radiologically according to Severin's criteria. There was progressive deterioration with age in both clinical function and radiographic appearance: 48.5% of hips showed evidence of dysplasia or subluxation at review. The results are similar to those found in a series treated by open reduction and limbectomy, differing only in the much lower incidence of degenerative changes after closed reduction

Only a few cases of palmar carpal subluxation associated with an ulnovolar fragment from the distal radius have been reported previously. We report a case which was treated operatively six months after the injury

1. Dislocation or sublaxation of the inferior radio-ulnar joint in association with fractures of the head of radius is discussed. 2. The incidence of the complication is greater than is generally supposed, and figures are given to support this finding. 3. The subluxation is not always associated with symptoms, and the degree of displacement may not be sufficient to be recognised clinically. 4. The anatomy and mechanism of the displacement have been investigated experimentally, and the results of the experiments are described

In order to treat painful subluxation or dislocation secondary to cerebral palsy, 11 patients (12 hips) underwent combined femoral and Chiari pelvic osteotomies with additional soft-tissue releases at a mean age of 14.1 years (9.1 to 17.8). Relief of pain, improvement in movement of the hip, and in sitting posture, and ease of perineal care were recorded in all, and were maintained at a mean follow-up of 13.1 years (8 to 17.5). The improvement in general mobility was marginal, but those who were able to walk benefited the most. The radiological measurements made before operation were modified afterwards to use the lateral margin of the neoacetabulum produced by the pelvic osteotomy. The radiological migration index improved from a mean of 80.6% (61% to 100%) to 13.7% (0% to 33%) (p < 0.0001). The mean changes in centre edge angle and Sharp’s angle were 72° (56° to 87°; p < 0.0001) and 12.3° (9° to 15.6°; p < 0.0001), respectively. Radiological evidence of progressive arthritic change was seen in one hip, in which only a partial reduction had been achieved, and there was early narrowing of the joint space in another. Painless heterotopic ossification was observed in one patient with athetoid quadriplegia. In seven hips the lateral Kawamura approach, elevating the greater trochanter, provided exposure for both osteotomies and allowed the construction of a dome-shaped iliac osteotomy, while protecting the sciatic nerve

We report four children aged two to nine years with traumatic tears of the transverse ligament of the atlas and atlanto-axial subluxation. This is extremely rare in this age group since trauma usually causes a skeletal rather than a ligamentous injury. The injuries resulted from falls or motor vehicle accidents, with considerable delay in diagnosis. Flexion radiographs showed atlas-dens intervals (ADI) of 6, 7, 8 and 13 mm; all four patients were treated by posterior fusion at C1-C2 after the failure of conservative treatment. In one child with quadriparesis and a fixed ADI of 13 mm, transoral anterior resection of the odontoid was performed before the fusion. Diagnosis of this traumatic lesion requires a high level of suspicion. Conservative treatment is likely to fail; surgical stabilisation is indicated

We describe a patient with fractures of both bones of the forearm in whom flexible intramedullary nail fixation of the radius alone led to ulnar malunion and a symptomatic distal radio-ulnar joint subluxation. This was successfully treated by ulnar osteotomy

Twenty-one patients with leg-length inequality underwent femoral lengthening using the Wagner technique. When reviewed, seven were found to have varying degrees of posterior subluxation of the knee. Critical assessment demonstrated that each of these was associated with a hypoplastic femur. It is postulated that posterior displacement of the tibia on the femur occurred as a result of the distal femoral and intraarticular bony deficiencies

Cervical myelopathy is an uncommon but potentially fatal complication of rheumatoid atlanto-axial subluxation. Computerised myelotomography with three-dimensional reconstruction shows that rheumatoid pannus, together with the odontoid peg, contributes significantly to anterior cervico-medullary compression. These findings were the basis for treatment by transoral anterior decompression and posterior occipitocervical fusion, which removes both bony and soft-tissue causes of compression and allows early mobilisation without major external fixation. We report encouraging results from this combined approach in 14 patients who had progressive neurological deterioration

The results obtained in a consecutive series of thirty-seven Pemberton operations for congenital dislocation or subluxation of the hip are reported. Over the period under review, 1967 to 1973, it was the only type of acetabuloplasty employed at Winford. Unless the mandatory concentric reduction could be obtained with ease, preliminary open reduction was favoured, especially in cases of primary care. Femoral rotation osteotomy was added for marked anteversion. The programme was designed to be complete inside fourteen weeks, and was so for eighteen hips. Secondary acetabuloplasty was performed on hips with instability or dislocation persisting despite previous treatment. The operations were performed from eighteen months to thirteen years of age. One initial failure required a repeat operation which was successful, but one severely dysplastic hip remained so. The average follow-up was six years

The clinical and radiological state of the hips of a group of children with cerebral palsy treated without operation is compared with that in a group treated by operation to correct adduction and flexion deformity and to obtain balanced action in the hip muscles. In the first group, 11 per cent of hips were dislocated, 28 per cent subluxated, 46 per cent dysplastic and 15 per cent normal. In the second group no hip was dislocated, 13 per cent were subluxated, 35 per cent dysplastic and 52 per cent normal. Surgical intervention is indicated clinically for a range of abduction diminishing to less than 45 degrees and–on radiological criteria–for early dysplastic changes, especially a break in Shenton's line, irrespective of the patient's age, severity of involvement or neurological maturity. Prevention of subluxation or dislocation improves function and diminishes the liability to develop a painful hip in adolescence or early adult life

We describe a rare form of congenital snapping knee. In six knees in four children, the tibia subluxed anteriorly on the femur when the knee was extended and reduced spontaneously on flexion. The abnormal movements were seen and felt as sudden snaps or clunks at about 30 degrees of flexion. All six knees showed similar dysplastic features, although the patients had different clinical syndromes. The mechanism of the subluxation and its management are discussed

Subluxation of the hip presenting for the first time in a child over the age of four years is rare. We report ten cases treated over nearly 11 years by the senior author (JAF). We describe the surgical procedures and the results, at maturity, of nine of the ten patients. At a mean follow-up of nearly nine years, the clinical outcome was good in all ten children by the criteria of Ponseti. Radiological assessment showed that three hips remained subluxed, and that four had avascular necrosis of the physis. We advise a one-stage procedure, correcting both the femur and acetabulum

1. A small personal consecutive series of children with congenital dislocation or subluxation of the hip who came for treatment at the age of over three years has been reviewed. The children have been kept under review up to the age of ten years or more. 2. A number of late results are illustrated. They lead to the conclusion that open operation is indicated in all these cases and that acetabuloplasty will effectively provide stability in most, particularly when combined with osteotomy of the femur with adduction angulation and lateral rotation. 3. It is still too early to assess the value of pelvic osteotomy of the Salter (1961) or Chiari (1955) type. 4. Capsular arthroplasty appears from Trevor's (1960) considerable experience to have a valuable place in patients over six years old

Thirty hips affected by congenital dislocation or subluxation underwent surgical treatment between the ages of five and fifteen years, and the results are presented. Reduction was aided by concurrent femoral shortening in seventeen. An aggressive approach in older children not only relieves the presenting symptoms in most, but also, by improving the anatomical relationships, increases the prospect of success should total replacement become indicated in the future

We reviewed 236 of the 388 Chiari pelvic osteotomies performed between 1953 and 1967 at the Orthopaedic University Clinic of Vienna for the treatment of congenital dislocation and subluxation of the hip. Over 90% of the operations were performed by Chiari himself. Twenty-one hips had needed reoperation after an average of 15.4 years; the other 215 hips had been followed up for 20 to 34 years (mean 24.8). The overall clinical results were excellent or good in 51.4%, fair in 29.8% and poor in 18.3%. The results were worse with increasing age at operation. The Trendelenburg sign improved only in patients aged seven or less at operation, and range of movement decreased in all cases. Subjectively poor results were seen in patients with pre-operative signs of osteoarthritis. Radiological loss of correction during follow-up was seen only in cases with incomplete primary correction. The addition of an intertrochanteric varus osteotomy in 36 cases did not achieve either better centering or better development of the acetabular roof. Degenerative changes increased significantly during the long-term follow-up, but their progress seemed to have been slowed down by the osteotomy in the younger age groups. Indications and contra-indications for the operation are discussed