Total arthroplasty was performed on 21 congenitally dislocated hips in 18 women. In all cases the femoral head was dislocated cranially at least one-fifth of the height of the pelvis. The components were both cemented, the acetabulum being replaced to its original position. The acetabular roof was reconstructed by bone graft in 13 hips, and trochanteric osteotomy was done in 18 hips. The patients were assessed at a median follow-up time of 7.5 years when their median age was 54 years. Nine patients had been revised or required revision. At follow-up the average functional score (according to Charnley) was 6 for pain, 4 for walking ability and 5 for range of motion. The Harris hip score was 82. The patients' subjective evaluation of their satisfaction with the late results on a visual analogue scale was 93, range 23 to 100. The high loosening rate in such patients demands regular follow-up and preparedness for revision surgery

We report the results at a mean of 24.3 years (20 to 32) of 61 previously reported consecutive total hip replacements carried out on 44 patients with severe congenital hip disease, performed with reconstruction of the acetabulum with an impaction grafting technique known as cotyloplasty. The mean age of the patients at operation was 46.7 years (23 to 68) and all were women. The patients were followed post-operatively for a mean of 24.3 years (20 to 32), using the Merle d’Aubigné and Postel scoring system as modified by Charnley, and with serial radiographs. At the time of the latest follow-up, 28 acetabular components had been revised because of aseptic loosening at a mean of 15.9 years (6 to 26), and one at 40 days after surgery because of repeated dislocations. The overall survival rate for aseptic failure of the acetabular component at ten years was 93.1% (95% confidence interval (CI) 86.5 to 96.7) when 53 hips were at risk, and at 23 years was 56.1% (95% CI 49.4 to 62.8), when 22 hips remained at risk. These long-term results are considered satisfactory for the reconstruction of an acetabulum presenting with inadequate bone stock and circumferential segmental defects.

Cite this article: Bone Joint J 2013;95-B:887–92.

Between 2003 and 2007, 99 knees in 77 patients underwent opening wedge high tibial osteotomy. We evaluated the effect of initial stable fixation combined with an artificial bone substitute on the mid- to long-term outcome after medial opening-wedge high tibial osteotomy (HTO) for medial compartmental osteoarthritis or spontaneous osteonecrosis of the knee in 78 knees in 64 patients available for review at a minimum of five years (mean age 68 years; 49 to 82). The mean follow-up was 6.5 years (5 to 10). The mean Knee Society knee score and function score improved from 49.6 (. sd. 11.4, 26 to 72) and 56.6 (. sd. 15.6, 5 to 100) before surgery to 88.1 (. sd. 12.5, 14 to 100) and 89.4 (. sd. 15.6, 5 to 100) at final follow-up (p <  0.001) respectively. There were no significant differences between patients aged ≥ 70 and < 70 years. The mean standing femorotibial angle was corrected significantly from 181.7° (. sd.  2.7°, 175° to 185°) pre-operatively to 169.7° (. sd. 2.4°, 164° to 175°) at one year’s follow-up (p < 0.001) and 169.6° (. sd. 3.0°, 157° to 179°) at the final follow-up (p = 0.69 vs one year). . Opening-wedge HTO using a stable plate fixation system combined with a bone substitute is a reliable procedure that provides excellent results. Although this treatment might seem challenging for older patients, our results strongly suggest that the results are equally good. Cite this article: Bone Joint J 2014;96-B:339–44

This chamber is designed for use with conscious or unconscious patients requiring treatment with oxygen under high pressure. It can be pressurised to a maximum of 45 pounds per square inch above ambient (60 pounds per square inch absolute). The unit consists of two parts, the pressure chamber and the control console, connected together by flexible hose. The chamber can be operated up to a distance of 100 feet from the control console and both parts are mobile. The chamber consists of two concentrically mounted transparent cylinders, closed at the ends by domed metal caps. One end cap is detachable and can be removed, complete with the bed. The bed will accommodate a patient 6 feet 6 inches tall. The fully transparent chamber allows a complete view of the patient during treatment. A communication system is provided between the patient and operators. A loud speaker and microphone are built into the door of the chamber and two external pick-up points are situated on the console and the fixed end cap of the chamber. Two-way or three-way conversation is possible and the patient can be temporarily isolated from the system if required. Oxygen and electrical services must be coupled to the console. The chamber will operate directly from oxygen cylinders charged to a maximum of 1,800 pounds per square inch or from any piped supply with a minimum pressure of 75 pounds per square inch absolute. A self-contained 12-volt direct current battery supplies the necessary electrical power. A charging unit is incorporated in the control console and this is normally connected to an alternating current supply to keep the battery fully charged. If initially the battery is fully charged the unit can be operated in a continuous pressurisation-depressurisation cycle for at least twenty-four hours without further charging. Pressurisation and depressurisation are achieved by means of a motorised valve on the outlet of the pressure chamber. During pressurisation a variable speed motor applies a gradually increasing load to a helical spring. This in turn loads the outlet valve. By this means smooth pressure changes are obtained and the motor speed can be used to control the rate of pressure change. Operating the pressure chamber is simple. After the patient has been placed in the chamber and the door sealed by screw-down knobs, pressurisation is started by turning a selector switch on the control console. The required working pressure can be preset or the pressure can be held at any point between ambient and the top working pressure of 45 pounds per square inch above ambient. Pressurisation stops automatically when the preset level is reached or at 45 pounds per square inch. The rate of pressurisation is selected on the console and can be varied up to a maximum of approximately 8 pounds per square inch per minute. In the same manner, depressurisation can be controlled at any rate up to 8 pounds per square inch per minute down to ambient pressure, or held at any intermediate pressure according to the wishes of the operator. Coloured lights on the control panel indicate whether the chamber is ready for use, in the pressurisation or depressurisation state, holding a steady pressure or holding at the chosen maximum pressure. This pressure chamber is run as an open circuit. A continuous ventilating flow of oxygen passes through the chamber to wash out carbon dioxide and water vapour. In the event of an emergency affecting the patient, fast depressurisation controls are provided on both the chamber and the console. An electrically operated dumping valve can be triggered from the control console or the same valve operated manually from the end of the chamber. A pressure drop of one pound per square inch per second is obtained when this valve is used, and it is possible to reduce from maximum pressure and remove the patient from the chamber in approximately one minute. If a total power failure should occur, a manually operated, slow depressurisation valve can be opened on the control console. A number of sealed electrical plugs are provided in the door of the chamber. With suitable apparatus these allow electro-physiological monitoring of the patient throughout the course of the treatment

Herniated intervertebral disc tissue has been shown to produce a number of proinflammatory mediators and cytokines, but there have been no similar studies using discs from patients with discogenic low back pain. We have compared the levels of production of interleukin-6 (IL-6), interleukin-8 (IL-8) and prostaglandin E. 2. (PGE. 2. ) in disc tissue from patients undergoing discectomy for sciatica (63) with that from patients undergoing fusion for discogenic low back pain (20) using an enzyme-linked immunoabsorbent assay. There was a statistically significant difference between levels of production of IL-6 and IL-8 in the sciatica and low back pain groups (p < 0.006 and p < 0.003, respectively). The high levels of proinflammatory mediator found in disc tissue from patients undergoing fusion suggest that production of proinflammatory mediators within the nucleus pulposus may be a major factor in the genesis of a painful lumbar disc

We evaluated the concentrations of chromium and cobalt ions in blood after metal-on-metal surface replacement arthroplasty using a wrought-forged, high carbon content chromium-cobalt alloy implant in 64 patients. At one year, mean whole blood ion levels were 1.61 μg/L (0.4 to 5.5) for chromium and 0.67 μg/L (0.23 to 2.09) for cobalt. The pre-operative ion levels, component size, female gender and the inclination of the acetabular component were inversely proportional to the values of chromium and/or cobalt ions at one year postoperatively. Other factors, such as age and level of activity, did not correlate with the levels of metal ions. We found that the levels of the ions in the serum were 1.39 and 1.37 times higher for chromium and cobalt respectively than those in the whole blood. The levels of metal ions obtained may be specific to the hip resurfacing implant and reflect its manufacturing process

On three occasions we have reviewed a series of knees after high tibial osteotomy for osteoarthritis: 99 were reviewed at one to two years; 81 at a mean of 5.7 years; and 65 at a mean of 11.9 years. At one to two years and at 5.7 years over 50% were good and over 75% acceptable. At 11.9 years, 43% were good and 60% acceptable. We determined the mechanical axis through the knee in maximum varus and maximum valgus; significantly better results were found if a mean angulation of 3 degrees to 7 degrees of valgus had been achieved at operation. We also measured intercondylar distances under varus and valgus stress, and found no significant lateral compartment narrowing. The best results were seen in knees with pre-operative grade I or grade II osteoarthritis and valgus deviation after osteotomy

We report the results of 62 hips in 62 patients (17 males, 45 females) with mean age of 62.4 years (37 to 81), who underwent revision of the acetabular component of a total hip replacement due to aseptic loosening between May 2003 and November 2007. All hips had a Paprosky type IIIa acetabular defect. Acetabular revision was undertaken using a Procotyl E cementless oblong implant with modular side plates and a hook combined with impaction allografting. . At a mean follow-up of 60.5 months (36 to 94) with no patients lost to follow-up and one died due to unrelated illness, the complication rate was 38.7%. Complications included aseptic loosening (19 hips), deep infection (3 hips), broken hook and side plate (one hip) and a femoral nerve palsy (one hip). Further revision of the acetabular component was required in 18 hips (29.0%) and a further four hips (6.4%) are currently loose and awaiting revision. . We observed unacceptably high rates of complication and failure in our group of patients and cannot recommend this implant or technique

Although it is clear that opening-wedge high tibial osteotomy (HTO) changes alignment in the coronal plane, which is its objective, it is not clear how this procedure affects knee kinematics throughout the range of joint movement and in other planes.

Our research question was: how does opening-wedge HTO change three-dimensional tibiofemoral and patellofemoral kinematics in loaded flexion in patients with varus deformity?Three-dimensional kinematics were assessed over 0° to 60° of loaded flexion using an MRI method before and after opening-wedge HTO in a cohort of 13 men (14 knees). Results obtained from an iterative statistical model found that at six and 12 months after operation, opening-wedge HTO caused increased anterior translation of the tibia (mean 2.6 mm, p <  0.001), decreased proximal translation of the patella (mean –2.2 mm, p <  0.001), decreased patellar spin (mean –1.4°, p < 0.05), increased patellar tilt (mean 2.2°, p < 0.05) and changed three other parameters. The mean Western Ontario and McMaster Universities Arthritis Index improved significantly (p < 0.001) from 49.6 (standard deviation (sd) 16.4) pre-operatively to a mean of 28.2 (sd 16.6) at six months and a mean of 22.5 (sd 14.4) at 12 months.

The three-dimensional kinematic changes found may be important in explaining inconsistency in clinical outcomes, and suggest that measures in addition to coronal plane alignment should be considered.

Cite this article: Bone Joint J 2014; 96-B:1214–21.

Peri-articular soft-tissue masses or ‘pseudotumours’ can occur after large-diameter metal-on-metal (MoM) resurfacing of the hip and conventional total hip replacement (THR). Our aim was to assess the incidence of pseudotumour formation and to identify risk factors for their formation in a prospective cohort study.

A total of 119 patients who underwent 120 MoM THRs with large-diameter femoral heads between January 2005 and November 2007 were included in the study. Outcome scores, serum metal ion levels, radiographs and CT scans were obtained. Patients with symptoms or an identified pseudotumour were offered MRI and an ultrasound-guided biopsy.

There were 108 patients (109 hips) eligible for evaluation by CT scan at a mean follow-up of 3.6 years (2.5 to 4.5); 42 patients (39%) were diagnosed with a pseudotumour. The hips of 13 patients (12%) were revised to a polyethylene acetabular component with small-diameter metal head. Patients with elevated serum metal ion levels had a four times increased risk of developing a pseudotumour.

This study shows a substantially higher incidence of pseudotumour formation and subsequent revisions in patients with MoM THRs than previously reported. Because most revision cases were identified only after an intensive screening protocol, we recommend close monitoring of patients with MoM THR.

We report the outcome of 32 patients (37 knees) who underwent hemicallostasis with a dynamic external fixator for osteoarthritis of the medial compartment of the knee. There were 16 men (19 knees) and 16 women (18 knees) with a mean age at operation of 54.6 years (27 to 72). The aim was to achieve a valgus overcorrection of 2° to 8° or mechanical axis at 62.5% (± 12.5%). At a mean follow-up of 62.8 months (51 to 81) there was no change in the mean range of movement, and no statistically significant difference in the Insall-Salvati index or tibial slope (p = 0.11 and p = 0.15, respectively). The mean hip-knee-ankle angle changed from 190.6 (183° to 197°) to 176.0° (171° to 181°), with a mean final position of the mechanical axis of 58.5% (35.1% to 71.2%).

The desired alignment was attained in 31 of 37 (84%) knees. There were 21 excellent, 13 good, two fair and one poor result according to the Oxford knee score with no correlation between age and final score. This score was at its best at one year with a statistically significant deterioration at two years (p = 0.001) followed by a small but not statistically significant deterioration until the final follow-up (p = 0.17). All the knees with Ahlback grade 1 osteoarthritis had excellent or good results. Complications included pin tract infections involving 16.4% of all pins used, delayed union in two, knee stiffness in four, fracture of the lateral cortex in one and ring sequestrum in one.

In conclusion, hemicallostasis provides precision in attaining the desired alignment without interfering with tibial slope or patellar height, and is relatively free of serious complications.

We have made a retrospective comparison between the results of 49 high tibial osteotomies and 42 unicompartmental replacement arthroplasties performed for the treatment of osteoarthritis of the knee, assessed 5 to 10 years after operation. The type of operation depended on the policy of the consultant responsible for treatment but analysis of the pre-operative findings showed that the two groups were sufficiently similar for direct comparison between them. In the replacement group, 32 (76%) were good, 4 were fair, 3 were poor and 3 had been revised. In the osteotomy group 21 (43%) were good, 11 were fair, 7 were poor and 10 had been revised. It was concluded that, in this series, the results of unicompartmental replacement were significantly better and that this group had shown no sign of late deterioration

We describe a rare herniation of the disc at the C2/C3 level in a 73-year-old woman. It caused hemicompression of the spinal cord and led to the Brown-Sequard syndrome. The condition was diagnosed clinically and by MRI six months after onset. Discectomy and fusion gave complete neurological resolution.

We have assessed the different adhesive properties of some of the most common bacteria associated with periprosthetic joint infection on various types of ultra high molecular Weight Polyethylene (UHMWPE). Quantitative in vitro analysis of the adhesion of biofilm producing strains of Staphylococcus aureus and Escherichia coli to physically and chemically characterised standard UHMWPE (PE), vitamin E blended UHMWPE (VE-PE) and oxidised UHMWPE (OX-PE) was performed using a sonication protocol. A significant decreased bacterial adhesion was registered for both strains on VE-PE, in comparison with that observed on PE, within 48 hours of observation (S. aureus p = 0.024 and E. coli p = 0.008). Since Vitamin E reduces bacterial adhesive ability, VE-stabilised UHMWPE could be valuable in joint replacement by presenting excellent mechanical properties, while reducing bacterial adhesiveness. Cite this article: Bone Joint J 2014;96-B:497–501

We report three patients having transoral fusion at C2/3 or C3/4 after fractures, with no infections or surgical complications and sound union. The operative technique and the relative merits of different approaches to the upper cervical spine are discussed and the transoral approach to the anterior aspect of the upper three cervical vertebrae is commended to the specialist surgeon.

1. Osteotomy for osteoarthritis of the hip induces a fibrin layer over the exposed bone which forms the basis of a fibrocellular protective mantle that can differentiate towards cartilage.

2. The process is accompanied by bone remodelling, which reduces sclerosis, resolves osteolytic foci and, in company with bone formation in the fibrous mantle, restores the subchondral plate.

3. Many important aspects of the pathogenesis of osteoarthritis and of its partial repair by osteotomy remain to be elucidated.

1. If osteoarthritis of the knee is confined mainly to one tibio-femoral compartment and the range of flexion is 90 degrees or more it can be treated safely and reliably by proximal tibial osteotomy.

2. The operation relieves pain in a large proportion of cases while retaining a useful range of knee flexion.

We are grateful to Miss H. M. Briggs, Research Secretary at Harlow Wood Orthopaedic Hospital, for secretarial assistance.

We report a case in which the popliteal artery was divided during upper tibial osteotomy performed with the knee in 90 degrees of flexion. This position is believed to allow it to fall safely back from the tibia, but we could find no published confirmation. We used duplex ultrasonography in ten healthy volunteers to measure the distance from the popliteal artery to the posterior surface of the tibia at various degrees of flexion of the knee. Our results showed that in 12 of 20 knees the popliteal artery was closer to the tibia in 90 degrees of knee flexion than in full extension. Surgeons performing upper tibial osteotomy should be aware that flexing the knee does not protect the popliteal artery from injury.

We reviewed the results of 71 revisions of the acetabular component in total hip replacement, using impaction of bone allograft. The mean follow-up was 7.2 years (1.6 to 9.7). All patients were assessed according to the American Academy of Orthopedic Surgeons (AAOS) classification of bone loss, the amount of bone graft required, thickness of the graft layer, signs of graft incorporation and use of augmentation.

A total of 20 acetabular components required re-revision for aseptic loosening, giving an overall survival of 72% (95% CI, 54.4 to 80.5). Of these failures, 14 (70%) had an AAOS type III or IV bone defect. In the failed group, poor radiological and histological graft incorporation was seen.

These results suggest that impaction allografting in acetabular revision with severe bone defects may have poorer results than have previously been reported.

1. Sixty-five cases of medial fracture of the femoral neck treated by substitution of the head by an acrylic prosthesis have been studied.

2. In general, the long-term clinical results of prosthetic arthroplasty after fresh fractures have been disappointing. The method has given slightly better results in the treatment of old fractures.

3. In view of the almost perfect results obtained after successful Smith-Petersen nailing in the presence of an adequate blood supply to the femoral head, it seems unjustifiable to abandon this principle for immediate substitution with an acrylic femoral head. Nevertheless it is believed that an arthroplasty of this type is justified in fractures seen late, and in fresh subcapital fractures when the fracture is irreducible. If a prosthesis is to be used, more protection for the stump of the neck against the strain of weight bearing is essential; a simple head prosthesis is inadequate, and a head with either a neck extension or an intramedullary prolongation may give better results.