HIP International

Tumoral calcinosis is an extremely rare benign condition that is characterised by deposits of calcium hydroxyapatite crystals in periarticular soft tissues. Although it is mainly located around large joints such as the hips, shoulders and elbows, it may also involve the small joints of hand and wrist. There are multiple types of tumoral calcinosis with divergent clinical characteristics but the exact cause is still unknown. We present a literature review to evaluate the location, clinical features, treatment options and results of surgical excision in this condition. Wide resection appears to lead to a good clinical outcome and a low incidence of local relapse.

We conducted a prospective single-blinded randomised controlled trial to compare the functional and quality of life outcomes in two groups of patients between 60 and 80 years of age undergoing THR; the first receiving a small head (28–32 mm) metal on polyethylene (MoP) articulation, and the second receiving a large head (44–54 mm) metal on metal (MoM) articulation. We recruited 49 patients and randomised them into one of the two groups (22 MoP and 27 MoM). The results demonstrated no statistical difference in any of the assessed functional outcomes at any follow-up point (p>0.05). There were no dislocations or revisions in either group. Although it has been suggested that large head MoM articulations in THA offer superior stability and function, our results suggest that small head MoP articulations can achieve comparable ROM, function and quality of life at short-term follow-up.

We report the three-year results of a new flexible, horseshoe-shaped acetabular cup, with a carbon fibre reinforced polyetheretherketone (CFR-PEEK) bearing surface. The 3 mm thick composite cup is designed to conserve acetabular bone stock and reproduce a near-physiological stress distribution to the adjacent bone. The cup is intended to articulate against a large diameter ceramic femoral head to produce a low-wear bearing couple that generates minimal wear debris.

A prospective, two-centre clinical study of the MITCH PCR cup was started in January 2007, to verify its safety and performance. Twenty-five MITCH PCR cups were implanted by three surgeons. There were 12 men and 13 women, with a mean age of 67.9 years (range 57.4 to 74.9). The mean Oxford hip score improved from 19.6 (SD 7.5) preoperatively to 43.5 (SD 7) at 3 years. The mean Harris hip score improved from 52.9 (SD 7) to 91.4 (SD 13.8) and the Euroqol-5D score increased from 62.6 (SD 18.4) to 82.8 (SD 19). One revision of the acetabular cup was undertaken at 21 months for squeaking. This has been investigated and modification of the articular geometry has resolved the problem, on in-vitro testing. Radiological analysis showed good early osseointegration of the MITCH PCR cup. However at three years, five cases of acetabular component migration and calcar resorption were observed. Three patients have subsequently undergone revision of the acetabular cup, at 41, 42 and 50 months respectively. The cause of the osteolysis is the subject of on-going investigation.

The aim of this study was to detect risk factors for ceramic liner fractures. 26 cementless ceramic on ceramic (COC) total hip arthroplasties (THA) revised because of ceramic liner fracture in 24 patients were compared with 49 well-functioning COC THA performed in 49 patients.

Demographic parameters, type of ceramic of the liner, size and neck length of the femoral head, cup abduction angle, cup anteversion, femoral off-set, height of the centre of rotation and the incidence of noisy hips during follow-up examination were compared.

A greater number of cups placed outside the optimal range of cup anteversion was found in the fracture group (p = 0.03). An audible noise was detected in 21 cases (80.7%) in the fracture group and in 3 cases (6.1%) in the non-fracture group (p = 0.001).

A cup anteversion angle out of the optimal range of 15°+/-10° was found to be a risk factor for ceramic liner fracture and the presence of a noisy hip frequently anticipated the failure. In our opinion neck-to-cup impingement with head subluxation and edge loading on the liner rim could have an important role in the onset of noise and subsequent liner failure, and cup malposition contributes to this mechanism of failure.

We assessed the efficacy of tranexamic acid in reducing transfusion requirements in patients undergoing revision hip arthroplasty. A prospective cohort study was designed comparing Tranexamic acid administration in 30 patients compared to 30 patients in a control group. Blood loss was measured in theatre, pre- and postoperative haemoglobin measurements were recorded and postoperative haemodynamic parameters were evaluated.

The mean postoperative haemoglobin was 9.5 g/dl in the tranexamic acid group and 8.2 g/dl in the control group (p<0.01). The mean haemoglobin reduction was 2.7 g/dl in the tranexamic acid group and 3.4 g/dl in the control group (p = 0.47). Mean transfusion requirements were 2.76 units in the study group and 4.0 units in the control group (p = 0.49) and the frequency of transfusion was reduced (p = 0.032). Infected revisions showed no reduction in transfusion requirements with tranexamic acid administration (p = 0.25). There was a reduced frequency of transfusion in patients when revision was performed for aseptic loosening (p = 0.027). This group of patients may benefit from tranexamic acid administration.

Debilitating arthritis in teenage patients is a complex problem with limited surgical options. Hip arthrodesis is unpopular amongst patients, and contemporary total hip arthroplasty (THA) may be a promising alternative. We report on the outcomes of THA in patients less than 20 years of age. All consecutive teenage patients undergoing THA at a tertiary referral centre were reviewed. Mean follow-up was 3.4 years (range 0.6–6.8) and 9 patients had at least 5 years follow-up. There were 51 THAs in 43 patients with a mean age of 17 years (range 12–19). The commonest indication was osteonecrosis (35 cases), mostly secondary to slipped upper femoral epiphysis (15 cases). Forty-six were uncemented and 5 were reverse hybrid THAs of which 7 were computer assisted design/manufacture (CADCAM) components. The commonest bearing surface used was ceramic on ceramic (40 cases). The survival rate was 96% and there were 2 complications. At latest follow-up, the mean Harris hip score was 90 (range 68–99) and UCLA activity score was 6 (range 4–9). Radiological analysis showed 2 patients with lucent lines around the acetabular component, but no signs of osteolysis or wear. We report good short to intermediate term survivorship and outcomes, and feel THA represents a valid alternative option to hip arthrodesis.

Total hip arthroplasty (THA) is a well established treatment for arthrosis of the hip, however many problems remain which have not yet been resolved, including component loosening and infection. Therefore, surgeons hesitate to perform THA in younger patients showing early signs of the disease. Intertrochanteric varus osteotomy was developed for osteoarthrosis with coxa valga. This procedure has been commonly used in patients with dysplastic hips. However, femoral head coverage is not sufficiently improved by this procedure. In order to overcome the disadvantages of this procedure, since 1972 we performed intertrochanteric varus osteotomy simultaneously combined with acetabuloplasty for the treatment of osteoarthrosis secondary to dysplasia.

Between 1969 and 1994, we performed 104 intertrochanteric varus osteotomies for prearthrosis and early stage arthrosis of the hip due to acetabular dysplasia in 84 patients. In this study, we reviewed these patients clinically and radiographically, over 15 years. The intertrochanteric varus osteotomy alone was employed in 38 hips (varus group). Combined intertrochanteric varus osteotomy and acetabuloplasty was employed in 63 hips (combined group).

The average Harris hip score at the latest follow-up in the combined group significantly higher than that in the ‘varus’ group. Postoperative centre-edge angle and age at operation were correlated with the Harris hip score at the most recent follow-up. The results of the present study indicate that this combined intertrochanteric varus osteotomy and acetabuloplasty for dysplastic hip should be considered in young patients when the disease is at an early stage.

Concerns have recently been raised about large head metal-on-metal total hip arthroplasties (LDH THA). Metal ion release due to wear may cause osteolysis, pseudotumours and necrosis. In addition, fixation of certain acetabular components is thought to be suboptimal.

We present the short term outcome of the Durom LDH THA. Retrospectively, a consecutive series of 64 implants in 60 patients was analysed with a mean follow-up of 37 months.

Clinical and radiological evaluation was performed on a regular basis, followed by additional evaluations when indicated. The 10-year revision percentage was calculated and compared with National Institute for Health and Clinical Excellence (NICE) standards.

Six patients (six hips) underwent cup revision (9%). Four of these cups showed no or minimal bone fixation. Three patients had a pseudotumour. In two revision cases, ALVAL (aseptic lymphocyte-dominated vasculitis-associated lesion) was present.

Lack of bone ingrowth and the presence of ARMD (adverse reaction to metal debris) seem to contribute to a high failure rate of the Durom LDH THA. The predicted ten-year revision rate of 14.2% (95% CI 5.6–22.8) is, given the broad confidence interval, not significantly outside NICE recommended standards. However, it is not clear which factors, if any, predict implant failure. Therefore, we do not advocate the use of this implant.

There is little information regarding the clinical performance of hip resurfacing arthroplasty (HRA) in older patients. Eighty-seven patients (99 hips) aged 65 years or older received HRA while a control group of 52 patients (64 hips) received a primary THA. The average age was 69.2 years for the HRA group and 71.9 years for the THA group. Follow-up ranged from 2 to 13 years. UCLA walking, function and activity scores and SF-12 scores were higher in the HRA group. At 10 years, the Kaplan-Meier overall survivorship rates were 96.7% for the HRA group and 91.2% for the THA group (p = 0.3174). We suggest considering hip resurfacing for patients 65 or older in centres where there is expertise in performing this procedure.

A planned change in the prosthesis used for hip hemiarthroplasty in one orthopaedic trauma unit from the Thompson prosthesis to the Exeter Trauma Stem (ETS) was studied. We completed a prospective continuous audit study comparing outcomes for patients undergoing the procedure before (766 patients) and after (388 patients) the change of practice. Outcomes measured included surgical complications (including infection or dislocation) and a postoperative radiographic review.

There was no difference in the incidence of surgical complications between the groups, and no difference in ratings given to postoperative radiographs between both groups. In theory, the ETS may be easier to revise, should this be required in future, but in other respects the devices are comparable.

Hip fractures remain one of the most devastating injuries in the elderly. Early prediction of outcome following hip fracture potentially results in more efficient health care. The aims of this study were to explore predictors of ambulation status at hospital discharge in patients ≥65 years of age operated on for fracture of the hip, and to investigate the impact of ambulation status at hospital discharge on 1-year mortality after hip fracture. We studied 344 patients who underwent surgery for hip fracture during a 12 month period. Multivariate regression analysis was used to explore predictive factors for ambulatory status at discharge, and 1-year mortality adjusted on important baseline variables. Cumulative 1-year mortality was significantly lower for patients in the ambulatory group when compared to patients in the non-ambulatory group. Patients who were older, had severe cognitive impairment, lower functional level before injury, and in whom postoperative delirium and pressure ulcers occurred had a higher chance of not recovering their gait ability at hospital discharge, and being dead 1 year after hip fracture.

Inability to walk at hospital discharge and presence of delirium are independent predictors of 1-year mortality. Every effort should be made to assure early mobilisation after hip fracture surgery, and prevention, prompt recognition and treatment of postoperative complications is important in order to facilitate better short-and long-term outcome.

While not proven definitively, the hypothesis that intra-articular psoas tendon release allows fluid to track into the retroperitoneal space has been widely accepted. This study attempts to identify the path through which fluid enters the pelvis and retroperitoneal space.

Six hemi-pelvis human cadaveric specimens were utilized for this study. 3 specimens underwent a capsulotomy and psoas tendon release, while 3 had only a capsulotomy. Arthroscopy fluid was combined with Barium and Methylene blue, and fluid was run at 50 mmHg for 2 hours. A gross dissection was performed at the end of the arthroscopy and the path of fluid flow into the pelvis and throughout the thigh was identified.

All 6 specimens showed extravasation of fluid into the pelvis at the 5 minute mark. Specimens with a psoas tendon release showed an altered pattern of fluid flow. In all three of these specimens, the psoas muscle belly was bright blue, along with the remaining tendon. Two of the 3 specimens showed tracking of fluid along the vasculature in both directions. The volume of fluid tracking into the pelvis was increased following a psoas release.

Arthroscopy fluid rapidly enters the pelvis following the initiation of hip arthroscopy, regardless of the status of the psoas tendon. Release of the psoas tendon allows fluid to diffuse into the psoas muscle and anterior medial thigh, tracking both proximally and distally along the neurovascular structures, and the volume of fluid tracking into the pelvis is increased following a psoas release.

Femoroacetabular impingement is caused by abnormal morphology of either the femur or acetabulum or both. Diagnostic criteria currently include an α angle of over 50° on a lateral radiograph. In this study, CT scans of symptomatic hips (n = 37) were compared with normal hips (n = 34) obtained from CT colonoscopy procedures. The femoral head described in terms of a three dimensional (3D) α angle and a 3D head neck margin (epiphysis) angle ‘3Dμ’ using a semi-automated algorithm.

In normal hips 70% have a maximum 3Dα angle of more than 50° at some point around their femoral head (mean 53° ± 5°, range 42° - 64°), while in cam hips, it was significantly larger (mean 69° ± 10°, range 54° – 94°, p<0.001). The 3Dμ also varied significantly and had a reverse relationship to that of the α angle: cam hips have an articular extent that crossed over spherical limit of the hip joint (mean minimum 41° ± 7°) while the articular margin of normal hips always remained within the spherical limit (mean minimum 49° ± 6°).

This semi-automated algorithm provides an objective measure of the femoral head in health and disease. It can reliably distinguish cam hips from normal, enabling cam hips to have their cam quantified and their surgery planned objectively.

The ability to measure acetabular cup orientation accurately during total hip arthroplasty represents a significant challenge. The aim of this research was to develop and evaluate a novel low cost mechanical device for measuring operative acetabular inclination. Cup implantation was simulated in two trials using the novel device: firstly involving surgeons and engineers orientating acetabular cups with sawbone pelves at a range of inclination angles (20°-55° in 5° increments); secondly in a simulated intra-operative scenario with surgeons. Target angles were compared with achieved angles and deviations from desired angles were recorded. In addition, all participants orientated cups under the same conditions using two other techniques: freehand and with a propriatory Mechanical Alignment Guide. In the first trial, the mean errors (deviations) using freehand technique, the mechanical alignment guide and the new device were 5.2° +/- 4.3° (range 0.1–22.0), 3.6° +/- 3.9° (range 0.1°–33.6°) and 0.5° +/- 0.4° (range 0.0–1.9) respectively. In the second trial, the mean error for freehand technique, mechanical alignment guide and the new device were 6.2° +/- 4.2° (range 0.2–18.2), 3.8° +/- 3.3° (range 0.0–19.1) and 0.6° +/- 0.5° (range 0.0–1.8) respectively. The new device has the potential to allow the surgeon to choose and record operative inclination accurately during total hip arthroplasty in the lateral decubitus position.