Stiffness is an uncommon but potentially debilitating complication following total knee replacement (TKR). The treatment of this condition remains difficult and controversial. We present the results of 13 patients who underwent open arthrolysis for stiffness. The mean time between TKR and arthrolysis was 14 months. The mean follow-up was 7.2 years (2 to 10). The mean range of movement prior to arthrolysis was 55°. This increased to 91°, six months after arthrolysis (p < 0.005). The improved range of movement was maintained during the follow-up period. No patient has required revision of their components. We have found arthrolysis to be a useful and successful approach to post-TKR stiffness.

We present the clinical and radiological results of percutaneous vertebroplasty in the treatment of 58 vertebral compression fractures in 51 patients at a minimum follow-up of two years. Group 1 consisted of 39 patients, in whom there was no associated intravertebral cleft, whilst group 2 comprised 12 patients with an intravertebral cleft. The Oswestry disability index (ODI) and visual analogue scale (VAS) scores were recorded prospectively. The radiological evidence of kyphotic deformity, vertebral height, leakage of cement and bone resorption around the cement were studied restrospectively, both before and after operation and at the final follow-up.

The ODI and VAS scores in both groups decreased after treatment, but the mean score in group 2 was higher than that in group 1 (p = 0.02 (ODI), p = 0.02 (VAS)). There was a greater initial correction of the kyphosis in group 2 than in group 1, although the difference was not statistically significant. However, loss of correction was greater in group 2. Leakage of cement was seen in 24 (41.4%) of 58 vertebrae (group 1, 32.6% (15 of 46); group 2, 75% (9 of 12)), mainly of type B through the basal vertebral vein in group 1 and of type C through the cortical defect in group 2. Resorption of bone around the cement was seen in three vertebrae in group 2 and in one in group 1. There were seven adjacent vertebral fractures in group 1 and one in group 2.

Percutaneous vertebroplasty is an effective treatment for osteoporotic compression fractures with or without an intravertebral cleft. Nonetheless, higher rates of complications related to the cement must be recognised in patients in the presence of an intravertebral cleft.

During hip resurfacing arthroplasty, excessive valgus positioning or surgical technique can result in notching of the femoral neck. Although mechanical weakening and subsequent fracture of the femoral neck are well described, the potential damage to the retinacular vessels leading to an ischaemic event is relatively unknown. Using laser Doppler flowmetry, we measured the blood flow in 14 osteoarthritic femoral heads during routine total hip replacement surgery, before and after notching of the femoral neck. In ten hips there was a reduction in blood flow of more than 50% from the baseline value after simulated notching of the femoral neck. Our results suggest that femoral head vascularity in the osteoarthritic state is similar to the non-arthritic state, where damage to the extraosseous vessels can predispose to avascular necrosis. Surgeons who perform resurfacing arthroplasty of the hip should pay careful attention to these vessels by avoiding excessive dissection around the femoral neck and/or notching.

We determined the effect of the surgical approach on perfusion of the femoral head during hip resurfacing arthroplasty by measuring the concentration of cefuroxime in bone samples from the femoral head. A total of 20 operations were performed through either a transgluteal or an extended posterolateral approach.

The concentration of cefuroxime in bone was significantly greater when using the transgluteal approach (mean 15.7 mg/kg; 95% confidence interval 12.3 to 19.1) compared with that using the posterolateral approach (mean 5.6 mg/kg; 95% confidence interval 3.5 to 7.8; p < 0.001). In one patient, who had the operation through a posterolateral approach, cefuroxime was undetectable.

Using cefuroxime as an indirect measure of blood flow, the posterolateral approach was found to be associated with a significant reduction in the blood supply to the femoral head during resurfacing arthroplasty compared with the transgluteal approach.

Metal ions generated from joint replacements are a cause for concern. There is no consensus on the best surrogate measure of metal ion exposure. This study investigates whether serum and whole blood concentrations can be used interchangeably to report results of cobalt and chromium ion concentrations.

Concentrations of serum and whole blood were analysed in 262 concurrent specimens using high resolution inductively-coupled plasma mass-spectrometry. The agreement was assessed with normalised scatterplots, mean difference and the Bland and Altman limits of agreement.

The wide variability seen in the normalised scatterplots, in the Bland and Altman plots and the statistically significant mean differences between serum and whole blood concentrations suggest that they cannot be used interchangeably. A bias was demonstrated for both ions in the Bland-Altman plots. Regression analysis provided a possible conversion factor of 0.71 for cobalt and 0.48 for chromium. However, even when the correction factors were applied, the limits of agreement were greater than ±67% for cobalt and greater than ±85% for chromium, suggesting that serum and whole blood cannot be used interconvertibly. This suggests that serum metal concentrations are not useful as a surrogate measure of systemic metal ion exposure.

The bicompartmental acetabulum is one of the morphological changes which may be seen in children with Legg-Calvé-Perthes’ disease. Three-dimensional CT and MRI were used to analyse the detailed morphology of the acetabulum with special reference to its inner surface, in 16 patients with Perthes’ disease and a bicompartmental acetabulum.

The bicompartmental appearance was seen on the coronal plane image through the acetabular fossa. The lunate surface was seen to grow laterally resulting in an increased mediolateral thickness of the triradiate cartilage. On the horizontal plane images, the acetabular fossa had deepened and had a distinct prominence at its posterior border. The combination of these morphological changes resulted in a bicompartmental appearance on plain radiography. Acetabular bicompartmentalisation appears to be the result of an imbalance of growth between the cartilage-covered lunate surface and the cartilage-devoid acetabular fossa.

We report the use of the reverse shoulder prosthesis in the revision of a failed shoulder hemiarthroplasty in 19 shoulders in 18 patients (7 men, 11 women) with severe pain and loss of function. The primary procedure had been undertaken for glenohumeral arthritis associated with severe rotator cuff deficiency.

Statistically significant improvements were seen in pain and functional outcome. After a mean follow-up of 44 months (24 to 89), mean forward flexion improved by 26.4° and mean abduction improved by 35°. There were six prosthesis-related complications in six shoulders (32%), five of which had severe bone loss of the glenoid, proximal humerus or both. Three shoulders (16%) had non-prosthesis related complications.

The use of the reverse shoulder prosthesis provides improvement in pain and function for patients with failure of a hemiarthroplasty for glenohumeral arthritis and rotator cuff deficiency. However, high rates of complications were associated with glenoid and proximal humeral bone loss.

We performed a randomised, prospective study of 80 mobile-bearing total knee arthroplasties (80 knees) in order to measure the effects of varus-valgus laxity and balance on the range of movement (ROM) one year after operation. Forty knees had a posterior-cruciate-ligament (PCL)-retaining prosthesis and the other 40 a PCL-sacrificing prosthesis. In the balanced group (69 knees) in which the difference between varus and valgus was less than 2°, the mean ROM improved significantly from 107.6° to 117.7° (p < 0.0001). By contrast, in the 11 knees which were unbalanced and in which the difference between varus and valgus laxity exceeded 2°, the ROM decreased from a mean of 121.0° to 112.7° (p = 0.0061). We conclude that coronal laxity, especially balanced laxity, is important for achieving an improved ROM in mobile-bearing total knee arthroplasty.

We compared the biological characteristics of extrinsic fibroblasts infiltrating the patellar tendon with those of normal, intrinsic fibroblasts in the normal tendon in vitro. Infiltrative fibroblasts were isolated from the patellar tendons of rabbits six weeks after an in situ freeze-thaw treatment which killed the intrinsic fibroblasts. These intrinsic cells were also isolated from the patellar tendons of rabbits which had not been so treated.

Proliferation and invasive migration into the patellar tendon was significantly slower for infiltrative fibroblasts than for normal tendon fibroblasts. Flow-cytometric analysis indicated that expression of α5β1 integrin at the cell surface was significantly lower in infiltrative fibroblasts than in normal tendon fibroblasts. The findings suggest that cellular proliferation and invasive migration of fibroblasts into the patellar tendon after necrosis are inferior to those of the normal fibroblasts. The inferior intrinsic properties of infiltrative fibroblasts may contribute to a slow remodelling process in the grafted tendon after ligament reconstruction.

Failure of total hip arthroplasty with acetabular deficiency occurred in 55 patients (60 hips) and was treated with acetabular revision using morsellised allograft and a cemented metal-backed component. A total of 50 patients (55 hips) were available for clinical and radiological evaluation at a mean follow-up of 5.8 years (3 to 9.5). No hip required further revision of the acetabular component because of aseptic loosening.

All the hips except one had complete incorporation of the allograft demonstrated on the radiographs. A complete radiolucent line of > 1 mm was noted in two hips post-operatively. A good to excellent result occurred in 50 hips (91%). With radiological evidence of aseptic loosening of the acetabular component as the end-point, the survivorship at a mean of 5.8 years after surgery was 96.4%.

The use of impacted allograft chips in combination with a cemented metal-backed acetabular component and screw fixation can achieve good medium-term results in patients with acetabular bone deficiency.

The object of this study was to develop a method to assess the accuracy of an image-free total knee replacement navigation system in legs with normal or abnormal mechanical axes. A phantom leg was constructed with simulated hip and knee joints and provided a means to locate the centre of the ankle joint. Additional joints located at the midshaft of the tibia and femur allowed deformation in the flexion/extension, varus/valgus and rotational planes. Using a digital caliper unit to measure the coordinates precisely, a software program was developed to convert these local coordinates into a determination of actual leg alignment. At specific points in the procedure, information was compared between the digital caliper measurements and the image-free navigation system. Repeated serial measurements were undertaken. In the setting of normal alignment the mean error of the system was within 0.5°. In the setting of abnormal plane alignment in both the femur and the tibia, the error was within 1°. This is the first study designed to assess the accuracy of a clinically-validated navigation system. It demonstrates in vitro accuracy of the image-free navigation system in both normal and abnormal leg alignment settings.

We validated the North American Spine Society (NASS) outcome-assessment instrument for the lumbar spine in a computerised touch-screen format and assessed patients’ acceptance, taking into account previous computer experience, age and gender.

Fifty consecutive patients with symptomatic and radiologically-proven degenerative disease of the lumbar spine completed both the hard copy (paper) and the computerised versions of the NASS questionnaire. Statistical analysis showed high agreement between the paper and the touch-screen computer format for both subscales (intraclass correlation coefficient 0.94, 95% confidence interval (0.90 to 0.97)) independent of computer experience, age and gender. In total, 55% of patients stated that the computer format was easier to use and 66% preferred it to the paper version (p < 0.0001 among subjects expressing a preference). Our data indicate that the touch-screen format is comparable to the paper form. It may improve follow-up in clinical practice and research by meeting patients’ preferences and minimising administrative work.

We report an independent prospective review of the first 230 Birmingham hip resurfacings in 212 patients at a mean follow-up of five years (4 to 6).

Two patients, one with a loose acetabular component and the other with suspected avascular necrosis of the femoral head, underwent revision. There were two deaths from unrelated causes and one patient was lost to follow-up. The survivorship with the worst-case scenario was 97.8% (95% confidence interval 95.8 to 99.5). The mean Harris hip score improved significantly (paired t-test, p < 0.05) from 62.54 (8 to 92) pre-operatively to 97.7 (61 to 100) at a mean of three years (2.1 to 4.3), then deteriorated slightly to a mean of 95.2 (47 to 100) at a mean of five years. The mean flexion improved from 91.5° (25° to 140°) to 110.4° (80° to 145°) at a mean of three years with no further improvement at five years (111.2°; 70° to 160°).

On radiological review at five years, one patient had a progressive lucent line around the acetabular component and six had progressive lucent lines around the femoral component. A total of 18 femoral components (8%) had migrated into varus and those with lucent lines present migrated a mean of 3.8° (1.02° to 6.54°) more than the rest. Superolateral notching of the femoral neck and reactive sclerosis at the tip of the peg of the femoral component were associated with the presence of lucent lines (chi-squared test, p < 0.05), but not with migration of the femoral component, and are of unknown significance.

Our results with the Birmingham hip resurfacing continue to be satisfactory at a mean follow-up of five years.

There are theoretical and practical advantages to modular rather than monoblock designs of prostheses for shoulder arthroplasty, but there are no reported studies which specifically compare the clinical and radiological results of their use. We have compared the results of unconstrained total shoulder arthroplasty for osteoarthritis using both types of implant. The monoblock design was used between 1992 and 1995 and the modular design after 1995. Both had cemented all-polyethylene glenoids, the monoblock with matched and the modular with mismatched radii of curvature. There were 34 consecutive shoulders in each group with a mean follow-up of 6.1 years in the first and 5.2 years in the second.

There were no significant differences in improvement of pain scores, active elevation, external rotation, internal rotation, patient satisfaction, or the Neer ratings between the two groups. Two of 28 glenoid components in the first group and six of 30 in the second met the criteria for being radiologically at risk for loosening (p = 0.25). There were no significant differences in clinical outcome or radiological changes between the first- and second-generation designs of implant for shoulder arthroplasty.

Between July 2000 and April 2004, 19 patients with bilateral spastic cerebral palsy who required an assistive device to walk had combined lengthening-transfer of the medial hamstrings as part of multilevel surgery. A standardised physical examination, measurement of the Functional Mobility Scale score and video or instrumented gait analysis were performed pre- and post-operatively. Static parameters (popliteal angle, flexion deformity of the knee) and sagittal knee kinematic parameters (knee flexion at initial contact, minimum knee flexion during stance, mean knee flexion during stance) were recorded. The mean length of follow-up was 25 months (14 to 45).

Statistically significant improvements in static and dynamic outcome parameters were found, corresponding to improvements in gait and functional mobility as determined by the Functional Mobility Scale. Mild hyperextension of the knee during gait developed in two patients and was controlled by adjustment of their ankle-foot orthosis. Residual flexion deformity > 10° occurred in both knees of one patient and was treated by anterior distal femoral physeal stapling. Two children also showed an improvement of one level in the Gross Motor Function Classification System.

We studied retrospectively the results of revision arthroplasty of the elbow using a linked Coonrad-Morrey implant in 23 patients (24 elbows) after a mean follow-up period of 55 months. According to the Mayo Elbow Performance Score, 19 elbows were satisfactory, nine were excellent and ten good. The median total score had improved from 35 points (20 to 75) before the primary arthroplasty to 85 points (40 to 100) at the latest follow-up. There was a marked relief of pain, but the range of movement showed no overall improvement. Two patients had a second revision because of infection and two for aseptic loosening. The estimated five-year survival rate of the prosthesis was 83.1% (95% confidence interval 61.1 to 93.3). Revision elbow arthroplasty using the Coonrad-Morrey implant provided satisfactory results but with complications occurring in 13 cases.

Gene therapy with insulin-like growth factor-1 (IGF-1) increases matrix production and enhances chondrocyte proliferation and survival in vitro. The purpose of this study was to determine whether arthroscopically-grafted chondrocytes genetically modified by an adenovirus vector encoding equine IGF-1 (AdIGF-1) would have a beneficial effect on cartilage healing in an equine femoropatellar joint model.

A total of 16 horses underwent arthroscopic repair of a single 15 mm cartilage defect in each femoropatellar joint. One joint received 2 × 10⁷ AdIGF-1 modified chondrocytes and the contralateral joint received 2 × 10⁷ naive (unmodified) chondrocytes. Repairs were analysed at four weeks, nine weeks and eight months after surgery. Morphological and histological appearance, IGF-1 and collagen type II gene expression (polymerase chain reaction, in situ hybridisation and immunohistochemistry), collagen type II content (cyanogen bromide and sodium dodecyl sulphate-polyacrylamide gel electrophoresis), proteoglycan content (dimethylmethylene blue assay), and gene expression for collagen type I, matrix metalloproteinase (MMP)-1, MMP-3, MMP-13, aggrecanase-1, tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) and TIMP-3 were evaluated.

Genetic modification of chondrocytes significantly increased IGF-1 mRNA and ligand production in repair tissue for up to nine weeks following transplantation. The gross and histological appearance of IGF-1 modified repair tissue was improved over control defects. Gross filling of defects was significantly improved at four weeks, and a more hyaline-like tissue covered the lesions at eight months. Histological outcome at four and nine weeks post-transplantation revealed greater tissue filling of defects transplanted with genetically modified chondrocytes, whereas repair tissue in control defects was thin and irregular and more fibrous. Collagen type II expression in IGF-1 gene-transduced defects was increased 100-fold at four weeks and correlated with increased collagen type II immunoreaction up to eight months.

Genetic modification of chondrocytes with AdIGF-1 prior to transplantation improved early (four to nine weeks), and to a lesser degree long-term, cartilage healing in the equine model.

The equine model of cartilage healing closely resembles human clinical cartilage repair. The results of this study suggest that cartilage healing can be enhanced through genetic modification of chondrocytes prior to transplantation.

We present the development and results of a nationwide, prospective, observational follow-up programme including patient-reported outcome measures (PROMs) for the Swedish Hip Arthroplasty Register. The programme started in 2002 and has gradually expanded to include all units performing total hip replacement in Sweden. The self-administered PROMs protocol comprises the EQ-5D instrument, the Charnley class categorisation and visual analogue scales for pain and satisfaction. These current analyses include 34 960 total hip replacements with complete pre- and one-year post-operative questionnaires.

Patients eligible for total hip replacement generally report low health-related quality of life and suffer from pain. One year post-operatively the mean EQ-5D index increased to above the level of an age- and gender-matched population, with a considerable reduction of pain (p < 0.001). Females, younger patients and those with Charnley category C reported a lower EQ-5D index pre-operatively than males, older patients and Charnley category A or B, respectively (all p < 0.001). In a multivariable regression analysis Charnley category C, male gender and higher age were associated with less improvement in health-related quality of life (p < 0.001).

Nationwide implementation of a PROMs programme requires a structured organisation and effective data capture. Patients’ response rates to the Registry are good. The continuous collection of PROMs permits local and national improvement work and allows for further health-economic evaluation.

We undertook a prospective pilot study to determine whether arthroscopic surgery through the central compartment of the hip was effective in the management of a snapping iliopsoas tendon. Seven patients were assessed pre-operatively and at three, six, 12 and 24 months after operation. This included the assessment of pain on a visual analogue scale (VAS) and function using the modified Harris hip score.

All the patients had resolution of snapping post-operatively and this persisted at follow-up at two years. The mean VAS score for pain fell from 7.7 (6 to 10) pre-operatively to 4.3 (0 to 10) by three months (p = 0.051), and to 3.6 (1 to 8) (p = 0.015), 2.4 (0 to 8) (p = 0.011) and 2.4 (0 to 8) (p = 0.011) by six, 12 and 24 months, respectively. The mean modified Harris hip score increased from 56.1 (13.2 to 84.7) pre-operatively to 88.4 (57.2 to 100) at one year (p = 0.018) and to 87.9 (49.5 to 100) at two years (p = 0.02). There were no complications and no weakness occurred in the musculature around the hip.

Our findings suggest that this treatment is effective and would support the undertaking of a larger study comparing this procedure with other methods of treatment.

This was a safety study where the hypothesis was that the newer-design CPCS femoral stem would demonstrate similar early clinical results and micromovement to the well-established Exeter stem. Both are collarless, tapered, polished cemented stems, the only difference being a slight lateral to medial taper with the CPCS stem. A total of 34 patients were enrolled in a single-blinded randomised controlled trial in which 17 patients received a dedicated radiostereometric CPCS stem and 17 a radiostereometric Exeter stem. No difference was found in any of the outcome measures pre-operatively or post-operatively between groups. At two years, the mean subsidence for the CPCS stem was nearly half that seen for the Exeter stem (0.77 mm (−0.943 to 1.77) and 1.25 mm (0.719 to 1.625), respectively; p = 0.032). In contrast, the mean internal rotation of the CPCS stem was approximately twice that of the Exeter (1.61° (−1.07° to 4.33°) and 0.59° (0.97° to 1.64°), respectively; p = 0.048). Other migration patterns were not significantly different between the stems. The subtle differences in designs may explain the different patterns of migration.

Comparable migration with the Exeter stem suggests that the CPCS design will perform well in the long term.