Of 44 patients (55 hips) with slipped upper femoral epiphysis treated from 1963 to 1989, 13 (14 hips) developed chondrolysis. Eight hips had chondrolysis at the time of presentation, all in female patients who were either coloured or black and who had moderate or severe slips. The other six hips had persistent pin penetration of the joint; in five of these the pin penetrated the anterosuperior quadrant of the head. Removal of penetrating pins resulted in improvement in pain in all six hips and in the range of movement in four. Chondrolysis did not develop in any of 11 hips with transient intraoperative pin penetration. In hips with chondrolysis maximum joint-space narrowing developed within the first year; improvement in joint space and range of movement continued for up to three years after maximal involvement. At an average follow-up of 13.3 years no patient had pain but five hips were stiff.

Two hundred patients with a meniscal lesion were peroperatively allocated to partial or total meniscectomy in a random manner. The results were compared at one year and at 6.3 to 9.8 years (median 7.8). After one year more patients with partial meniscectomy (90%) than with total meniscectomy (80%) had no complaints. At the later review these figures were 62% and 52%, respectively (p = 0.18). However, patients with partial meniscectomy had higher functional scores. The deterioration in function between the first review and the second showed no significant difference in the two treatment groups. The incidence of mediolateral instability rose from 8% to 47% and was more frequent after total than after partial meniscectomy. Between the two reviews the radiological signs of knee degeneration increased with no difference between the two treatment groups.

Of 142 Chiari pelvic osteotomies for osteoarthritis in dysplastic hips, most performed by Chiari himself, we were able to review 82 and obtain information about 18 by questionnaire. All patients were over 30 years of age at operation; follow-up averaged 15.5 years. Twenty hips had undergone secondary total hip replacement. The outcome was good in 75%, fair in 9% and poor in 16%. High osteotomies all gave good results, and the result also depended on adequate medialisation. Statistics were worse for patients over 44 years of age at the time of operation. For osteoarthritis secondary to hip dysplasia, the Chiari pelvic osteotomy is an alternative procedure to early hip replacement. In contrast to intertrochanteric osteotomy, it has the advantage of facilitating the implantation of an acetabular prosthesis should arthroplasty become necessary at a later stage.

For equinus deformity in spastic hemiplegia, correction by the White slide technique has been studied in a group of 35 patients followed up for 14 to 20 years. It is a simple, effective method of lengthening the calcaneal tendon, and is free from significant complications with an acceptable rate of recurrent deformity. The majority of patients achieved a heel-toe gait.

Excision of the lunate was performed for 18 patients with Kienbock's disease; 14 were followed up for an average of almost 12 years. Carpal collapse progressed with time, but rearrangement of the remaining carpal bones preserved a satisfactory range of movement and grip strength. Degenerative changes were not severe. All the patients had relief of pain, were able to carry out their normal activities, and all but two could perform strenuous activities.

Eight women had 10 toes treated for hallux rigidus by dorsal wedge osteotomy of the proximal phalanx and were reviewed after an average follow-up of 22 years. Five toes were symptom-free, four others did not restrict walking, and only one had required metatarsophalangeal fusion. We conclude that dorsal wedge osteotomy affords long-lasting benefits for hallux rigidus in the adolescent female.

We have followed up a series of total hip arthroplasties performed for secondary osteoarthritis and analysed the results in relation to the osteoblastic response to the disease. This was assessed pre-operatively from the radiographic appearance, according to Bombelli's criteria (1983). Of 63 hips in 55 patients followed up for five to 13 years, 17 were hypertrophic, 24 normotrophic and 22 atrophic in type. The atrophic-type hips showed a high incidence of acetabular loosening, leading to unsatisfactory clinical results in 32%. By contrast, the hypertrophic-type hips had a low incidence of acetabular loosening, while the normotrophic type showed intermediate results. It was concluded that the osteoblastic response to osteoarthritis is closely related to acetabular loosening and to late clinical failure.

We present the results of 506 consecutive Howse hip arthroplasties with a minimum follow-up of 10 years. The mortality within one month of surgery was 0.79%. The early dislocation rate was 1.38%, two hips requiring revision. Nine hips developed deep sepsis (1.78%), eight of which required revision. At 10 years 42 hips (8.3%) had required revision, including 14 with aseptic acetabular loosening and 11 with femoral stem fractures. We feel that as judged by the dislocation rate and the need for subsequent revision, the Howse arthroplasty is an acceptable form of total hip replacement, particularly in the older patient and in those requiring total replacement for femoral neck fractures.

Tectoplasty is a new acetabuloplasty which aims to provide an extra-articular weight-bearing surface in cases of dysplastic acetabulum, hip subluxation or dislocation with a false acetabulum. The lateral wall of the iliac bone at the lateral edge of the affected acetabulum is raised as a proximally-based flap and massive bone grafts are inserted to provide a congruous, non-absorbable roof for the capsule and femoral head. An advantage is that the weight-bearing surface can be formed away from the original acetabulum, wherever the dislocated or subluxated femoral head may lie. Of 34 hips with congenital dislocation or severe subluxation treated by this method, 27 were evaluated after an average follow-up of 12 years. At review the patients averaged 35 years of age and satisfactory results with good relief of pain had been obtained in 78%. The results were unsatisfactory when degenerative changes had already developed before operation. Tectoplasty is indicated for pain due to congenital subluxation or dislocation of the hip under the age of thirty, in the absence of advanced osteoarthritis.

Seventy resistant club feet in 46 patients were treated within the first six months of life by posterior release as an incident in continuing conservative care and were later assessed at an average age of 15 years. Assessment was made upon strict clinical criteria, including appearance, function and degree of pain during activity; the results were excellent in 22 feet, good in 19, and poor in 29. We also studied the correlation between the radiographs and the final outcome. From these data we propose certain indications for the timing and technique of this type of management, and also discuss the relative merits of this approach compared with more conventional radical release operations.

Clinical assessment of equinus in children before and after operation was made over a twenty-year period (1958-1978), and three groups were defined. Forty-three muscles (Group I) had abnormal shortening without spasticity and the deformity progressed steadily despite immediate improvement after operation; this was considered to be the result of a lack of muscle growth during bone growth. Forty-one muscles (Group II) had both shortening and spasticity with an imbalance which might be unchanged after operation, or reversed or improved. Fourteen muscles (Group III) had spasticity only and progression was unpredictable and could not be defined. Improvement in gait was regularly observed in Group I in the early years after operation. In Groups II and III the results were variable. These results did not depend on surgical technique but on differences in pathophysiology.

We evaluated the outcome of partial lateral meniscectomy of 31 knees in 29 patients whose knees were otherwise normal. The mean follow-up was 10.3 years.

According to the Lysholm score, 14 knees were rated as excellent, four as good, five as fair and eight as poor, with a mean score of 80.5 points. Radiologically, only one lateral compartment was classified as grade 0, eight as grade 1, nine as grade 2, 11 as grade 3, and two as grade 4 according to Tapper and Hoover. No significant (p < 0.05) correlation was found between the amount of tissue resected and the subjective, clinical and radiological outcome.

Although early results of lateral meniscectomy may be satisfactory, we have demonstrated that in the long term there was a high incidence of degenerative changes, a high rate of reoperation (29%) and a relatively low functional outcome score.

We reviewed a consecutive series of 527 uninfected hip replacements in patients resident in the UK which had been implanted from 1981 to 1993. All had the same basic design of femoral prosthesis, but four fixation techniques had been used: two press-fit, one HA-coated and one cemented. Review and radiography were planned prospectively. For assessment the components were retrospectively placed into two groups: those which had failed from two years onwards by aseptic femoral loosening and those in which the femoral component had survived without revision or recommendation for revision.

All available radiographs in both groups were measured to determine vertical migration and examined by two observers to agree the presence of radiolucent lines (RLLs), lytic lesions, resorption of the neck, proximal osteopenia and distal intramedullary and distal subperiosteal formation of new bone. We then related the presence or absence of these features and the rate of migration at two years to the outcome with regard to aseptic loosening and determined the predictive value of each of these variables.

Migration of ≥2 mm at two years, the presence of an RLL of 2 mm occupying one-third of any one zone, and subperiosteal formation of new bone at the tip of the stem were predictors of aseptic loosening after two years. There were too few lytic lesions to assess at two years, but at five years a lytic lesion ≥2 mm also predicted failure. We discuss the use of these variables as predictors of femoral aseptic loosening for groups of hips and for individual hips.

We conclude that if a group of about 50 total hip replacements, perhaps with a new design of femoral stem, were studied in this way at two years, a mean migration of < 0.4 mm and an incidence of < 10% of RLLs of 2 mm in any one zone would predict 95% survival at ten years.

For an individual prosthesis, migration of < 2 mm and the absence of an RLL of ≤2 mm at two years predict a 6% chance of revision over approximately ten years. If either 2 mm of migration or an RLL of 2 mm is present, the chances of revision rise to 27%, and if both radiological signs are present they are 50%. If at five years a lytic lesion has developed, whatever the situation at two years, there is approximately a 50% chance of failure in the following five years.

Our findings suggest that replacements using a limited number of any new design of femoral prosthesis should be screened radiologically at two years before they are generally introduced. We also suggest that radiographs of individual patients at two years and perhaps at five years should be studied to help to decide whether or not the patient should remain under close review or be discharged from specialist follow-up.

We report a clinical and radiological survival analysis of 148 consecutive revisions of hip arthroplasties. All patients referred were offered revision if it was indicated and they were medically fit. About one-third (32%) had had at least one previous revision, and about one-third had an established deep infection. The revisions were performed in ultra-clean air with body-exhaust suits. The usual method of fixation was by contained and pressurised cement of standard viscosity, to which appropriate antibiotics had been added in infected cases. Some patients had cementless revision. Clinical failure meant that one or both of the implants had been removed; radiological failure was assessed from serial radiographs. The clinical survival at ten years was 95%. The Merle D'Aubigne and Postel rating for pain improved from a mean of 2.9 to 5.2; and in Charnley group A and B cases, walking ability improved from 2.3 to 4.3. In contrast to some reports we also found good radiological survival; this was 90.5% for cemented femoral stems. Isoelastic revision stems inserted without cement gave poor results.

In the 1950s Frederick Dwyer evolved the concept of treating resistant and relapsed clubfoot by osteotomy of the calcaneum. He published the results of his medial opening wedge procedure in 1963 with a mean follow-up of five years. We present the structured, radiographic and functional results at a mean elapsed time of 27 years of 36 feet (26 patients) all operated on by Dwyer. Their mean Laaveg and Ponseti (1980) grading was 83.7%. In 94% the heel was in neutral or valgus and 86% of the feet were plantigrade. A good range of movement was present in the ankle and subtalar joints in 83%.

We excised the anterior cruciate ligament from the left stifle of 24 sheep and replaced it by a polyester fibre implant routed 'over the top' of the femoral condyle and fixed, using grommets and screws. All the joints were sound, and the animals moved normally until they were killed at six, 12 and 24 months after operation. We found that the implants were always covered by host tissue, which matured into bundles with a histological appearance similar to the natural ligament. The implants were joined to the bones by organised fibrous tissue and there was no anchorage loosening. There was no synovitis, but the operated joints showed progressive cartilage degeneration. The reconstructed joints became less stable immediately after operation, but regained normal stability as the neoligaments developed. The neoligaments lost strength with time, despite tissue ingrowth. The good functional, biomechanical, and histological results justify clinical trials of this type of implant.

We determined the cumulative survival rates, in arthroplasty of the knee, of three designs of tibial component, using a change of position on standard radiographs or revision for aseptic loosening as criteria of failure. The average migration of each of the three designs in the first postoperative year is known from roentgen stereophotogrammetric analysis reported by other authors. The ranking order of the components as judged by cumulative survival is the same as that determined by early migration. This finding supports the view that the measurement of early migration can predict late aseptic loosening and therefore that such measurements are clinically of value.

From 1970 to 1978, 29 patients had a unilateral operation for bilateral recurrent dislocation of the patella. We examined 21 of them at a mean of 14 years postoperatively. Eighteen of these patients had evidence of generalised joint laxity. Six of the operated knees and four of the unoperated knees still had recurrent dislocations. The operated knees were clinically worse, with a significantly higher incidence of osteoarthritis. We concluded that the operations used to treat recurrent dislocation of the patella may have had short-term benefits, but did not cure the patients in the long term.

We reviewed the cases of 38 children with 45 congenitally dislocated hips who presented for primary treatment after the age of three years. Of these, 34 hips were managed by the 'direct approach' of Somerville and Scott (1957); 14 of these required secondary operations for subluxation, often with a poor outcome. Eleven hips were treated by combined pelvic and femoral osteotomy which, in general, gave good results. At a mean follow-up of 16.7 years, 80% of the whole series had a good or excellent clinical result and 51% were good or excellent radiologically. Simultaneous correction both above and below the hip is considered to be the best treatment for the older child with congenital hip dislocation.