Aims

The aims of this study were to measure sagittal standing and sitting lumbar-pelvic-femoral alignment in patients before and following total hip arthroplasty (THA), and to consider what preoperative factors may influence a change in postoperative pelvic position.

1. Stainless steel mould arthroplasty of the knee is described and a ten-year follow-up study of sixty-two operations is reported. Fifty-four were for rheumatoid arthritis and eight for osteoarthritis. 2. Forty-nine of the sixty-two joints retained mobility, six had become ankylosed and five were later arthrodesed ; two limbs were amputated. The forty-nine mobile knees included twenty-seven which were painless at all times, and fourteen in which only an occasional twinge was felt. 3. The range of movement was increased in twenty-two joints as compared with the state before operation, diminished in twelve and unaltered in five. In ten knees measurements before operation were not available. 4. Flexion deformity, swelling, stability and function were improved in a significant number of joints. 5. Patients suffering from active rheumatoid arthritis often found that the joint operated upon no longer took part in generalised flares of the disease

1. Attention is drawn to the powers of resistance of the growing ends of bones in suppurative pyogenic arthritis of the knee and hip in infancy. 2. It is emphasised that a translucent zone in the radiograph does not necessarily mean that this part of the bone, epiphysial cartilage or plate is destroyed. 3. Diagnostic criteria are described to confirm that cartilage or decalcified bone has survived the infection in the knee joint. 4. The prognosis for the knee joint is discussed. 5. The hip joint presents greater difficulties in diagnosis and greater issues are at stake. It is recommended therefore that the hip joint be manipulated or explored if the radiograph and the physical signs suggest that destruction of the joint has either caused dislocation or has so damaged it that dislocation is likely to occur in the future. In favourable cases stability may be restored to the hip. In the others a diagnosis of irreparable destruction is established and the surgeon is satisfied that an opportunity to help the patient has not been lost

Aims

The sacrum is frequently invaded by a pelvic tumour. The aim of this study was to review our experience of treating this group of patients and to identify the feasibility of a new surgical classification in the management of these tumours.

We reviewed prospectively cemented stem revision in 106 patients with severe femoral endosteal bone lysis without infection. Bone grafts were not used in any of the patients. The minimum follow-up was three years (mean 6 years 4 months). At the last review 76.4% of the patients were free of pain and 17.9% had only mild or occasional discomfort; radiographs showed well-fixed stable stems in 101 (95.3%). An intramedullary cement plug was used at revision to improve stability in 97.7%. There was new endosteal osteolysis after revision in 17 patients; only two had severe changes. Seven hips (6.6%) required a second revision; only four of these (3.8%) were for stem loosening. Survivorship of the revised stem, using radiological evidence of stem loosening as the end point, was 95.8% at seven years. The results of stem revision arthroplasty using cement in the presence of massive endosteal cavitation are satisfactory

The Gamma nail was designed to treat unstable intertrochanteric and subtrochanteric fractures. The device was developed after cadaver studies and has been used clinically since February 1985 in a total of 421 patients. The results in 123 patients treated by the third version of this design are reported. The Gamma nail transmits weight closer to the calcar than does the dynamic hip screw and it has greater mechanical strength. A semi-closed operative technique is used, with an average duration of operation of 35 minutes and little blood loss. Distal locking screws can be used to maintain rotational stability, and can be inserted without the use of an image intensifier. Results showed satisfactory fracture union with little loss of position, even in comminuted fractures. Operative complications were few, but included fractures of the base of the greater trochanter. The most important postoperative complication, seen in one case, was fracture of the shaft of the femur at the distal end of the nail, but this healed well after re-nailing

The Oxford Knee, a resurfacing prosthesis with a meniscal bearing, can be used for either bicompartmental or unicompartmental arthritis. The first 103 unicompartmental cases are presented at a mean time since operation of 36 months (range 21 to 56 months). In those cases with surviving arthroplasties, pain was relieved in 96%. The full range of pre-operative flexion was maintained and flexion deformity was improved from a mean of 6.7 to 5.4 degrees. Stability and alignment were restored to normal in nearly all the knees. Absence of the anterior cruciate ligament was associated with a significantly greater incidence of failure. Six failures occurred in 37 knees lacking a normal anterior cruciate ligament (16.2%); three occurred in 63 knees with a normal anterior cruciate ligament (4.8%) (p less than 0.02). Criteria for the future selection of patients have been deduced from our experience. The operation is recommended for knees with severe unicompartmental osteoarthritis in which all the ligaments are still intact

We have developed an apparatus to measure the anteroposterior stability of the knee to forces of up to 250 N, applied at 20 degrees of flexion. We measured anterior laxity at 200 N, anterior stiffness at 50 N and total laxity at +/- 200 N. A study of cadaveric knees revealed that the soft tissues surrounding the bones had a significant influence on the force-displacement curve, and emphasised that differences between injured and normal pairs of knees are much more important than the absolute values of the parameters. In 61 normal volunteers we found no significant left to right differences in anterior laxity at 200 N and anterior stiffness at 50 N. In 92 patients with unilateral anterior cruciate deficiency there were significant differences (p less than 0.0005) in anterior laxity, anterior stiffness and total laxity, the injured-normal differences averaging 6.7 mm, 1.3 N/mm, and 8.1 mm respectively

Consecutive patients with a confirmed rupture of at least one of the lateral ligaments of the ankle were randomly assigned to receive either operative or functional treatment. They were evaluated at a median of 8 years (6 to 11). In total, 370 patients were included. Follow-up was available for 317 (86%). Fewer patients allocated to operative treatment reported residual pain compared with those who had been allocated to functional treatment (16% versus 25%, RR 0.64, CI 041 to 1.0). Fewer surgically-treated patients reported symptoms of giving way (20% versus 32%, RR 0.62, CI 0.42 to 0.92) and recurrent sprains (22% versus 34%, RR 0.66, CI 0.45 to 0.94). The anterior drawer test was less frequently positive in surgically-treated patients (30% versus 54%, RR 0.54, CI 0.41 to 0.72). The median Povacz score was significantly higher in the operative group (26 versus 22, p < 0.001). Compared with functional treatment, operative treatment gives a better long-term outcome in terms of residual pain, recurrent sprains and stability

Objectives

In this prospective cohort study, we investigated whether patient-specific finite element (FE) models can identify patients at risk of a pathological femoral fracture resulting from metastatic bone disease, and compared these FE predictions with clinical assessments by experienced clinicians.

The hip problems in 116 children with myelomeningocele are discussed. The management described stresses the importance of selection of the type of operation; major surgery is appropriate only for those children who benefit significantly, and this generally means only those with strong quadriceps muscles on both sides. Some children with acetabular dysplasia gain immediate stability if acetabuloplasty is combined with other hip operations. Children who lack strong quadriceps muscles are best served by simpler procedures, such as tendon excision, designed to rid them of fixed deformity and to prevent recurrent deformity. The operations described are performed whenever possible under one anaesthetic and are combined with any other limb operation that may be necessary. It is suggested that the aim in management is not the treatment of paralytic dislocation of the hip but the correction of fixed deformity so that the child can stand with a stable posture. Subluxation and dislocation are treated incidentally to procedures designed to prevent or correct fixed deformity

The records of 243 patients with Thompson prostheses for displaced femoral neck fractures have been studied. One hundred and seven prostheses were inserted through an anterior approach and 136 by a posterior approach. The short-term results and complications in these otherwise comparable groups are discussed. The infection rate of 18·5 per cent in the group operated upon by the posterior approach was thrice that after operations by the anterior route (6·5 per cent infected). Drained wounds had significantly less infection (6·3 per cent) compared with the undrained group (28 per cent infected). Other factors influencing the infection rate are discussed. The anterior approach offered greater stability. Of the twenty dislocations in the series, nineteen followed operations by the posterior approach. The mortality rate six weeks after operation was 6·5 per cent after the anterior approach and 20·6 per cent after the posterior approach. Statistical analysis significantly favours the anterior approach

The incidence and prognostic significance of fractures of acrylic cement related to the stem of a femoral head prosthesis in total hip replacement are examined. These fractures are demonsfrated when the cement has been rendered radio-opaque by the addition of barium sulphate. One and a half per cent of the radiographs of 6,649 patients showed these fractures, which were sometimes associated with subsidence of the prosthesis. Fracture of the cement was usually evident at the six-month post-operative review, if it occurred at all. This radiological complication was devoid of symptoms in the majority of cases and tended to occur in patients with excellent functional recovery. In a minority of patients pain in the thigh during the first six months seemed likely to be explained by this fracture. Slight subsidence of the prosthesis in the cement bed appeared to result in a new and final position of stability. The prognosis was very good; only when separation of the fracture exceeded about 4 millimetres was the prognosis doubtful, in which case a chronic deep infection might be suspected. Possible mechanical and structural causes of fracture of the cement are discussed

1 . A preliminary report is presented of a clinical trial to compare the results of early and late weight bearing in randomly selected patients of comparable age groups whose displaced femoral neck fractures were treated by internal fixation with a sliding nail-plate. 2. When 124 patients were assessed at three months and 107 at six months after operation there was no significant difference between those who started unguarded weight bearing two weeks after operation and those who avoided weight bearing for three months. 3. Early weight bearing appears to have no harmful effect on the early post-operative stability of this fracture when a sliding nail-plate is used for fixation. 4. Further information is necessary before any conclusion can be reached about the effect of early weight bearing on the ultimate fate of the fracture and of the femoral head. For this reason, and also to increase the numbers of patients in the series, the trial is continuing and the patients are being followed up for a three-year period

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

To investigate the effect of instability on the remodelling of a minor articular surface offset, we created a 0.5 mm coronal step-off of the medial femoral condyle in 12 New Zealand white rabbits and transected the anterior cruciate ligament (ACL). A control group of 12 rabbits had only ACL resection and the opposite knee was used as the non-operated control. The osteoarthritic changes at 6, 12 and 24 weeks after surgery were evaluated histologically. In addition, changes in the immunological detection of 3-B-3(-) and 7-D-4 chondroitin-6-sulphate epitopes were determined because of the previous association of such changes with repair of cartilage and early osteoarthritis. In the instability/step-off group there was rapidly progressing focal degeneration of cartilage on the high side of the defect, not seen in previous step-off studies in stable knees. The rest of the femoral condyles and the tibial plateaux of the instability/step-off group had moderate osteoarthritis similar to that of the instability group. 3-B-3(-) was detectable in the early and the intermediate stages of osteoarthritis but no staining was seen in the severely damaged cartilage zones. Immunoreactivity with 7-D-4 increased as degeneration progressed. Our findings have shown that even a minor surface offset may induce rapid degeneration of cartilage when the stability of the knee is compromised

Aims

The aim of this study was to evaluate antegrade autologous bone grafting with the preservation of articular cartilage in the treatment of symptomatic osteochondral lesions of the talus with subchondral cysts.

Seven subjects with normal joints were tested for active and passive position sense of ankle inversion, peroneal reflex reaction time to sudden ankle inversion, and postural stability during single-leg stance. The tests were performed before and after regional block of the ankle and foot with local anaesthetic. Passive position sense, assessed with the muscles relaxed, was greatly impaired by anaesthesia but active position sense, with the calf muscles activated, was preserved, and the peroneal reaction time to sudden ankle inversion was not altered. The magnitude of postural sway during single-leg stance was also unchanged by anaesthesia of the ankle and foot. The results suggest that the afferent input from intact lateral ankle ligaments is important in sensing correct placement of the foot at heel-strike, but that this input can be replaced by afferent information from active calf muscles. Afferent input from these muscles seems also to be responsible for dynamic ankle protection against sudden ankle inversion and is adequate to allow stable single-leg stance