Aim: Alumina ceramic on ceramic bearings have gained popularity in hip arthroplasty due to the properties of low wear, low friction and chemically inert wear debris. In a previous study, we reported the excellent clinical results of a series of cementless ceramic on ceramic primary total hip arthroplasties at a minimum of 5 years. We now present the follow up results at 10 years.

Method: Between June 1997 and February 1999, 301 consecutive, primary cementless hip arthroplasties were performed on 283 patients in our unit. The mean age of the patients was 57.8 years, with 145 (51%) being female. All of the hips received the same implant: (Osteonic ABC cup and Secure-Fit or Secure-Fit Plus stem; Stryker Orthopaedics). A third generation alumina ceramic on ceramic bearing (Biolox Forte; CeramTec) was used for articulation in all cases. All the operations were performed through a posterior approach with enhanced posterior repair, and the post-operative protocols were the same for all the patients. The clinical and radiographic outcome at 10 years were analysed.

Results: At 10 years, 7.3% had died of unrelated cause and 3% were revised. The average Harris Hip score was 94.3 points at the last follow up. Ninety six percent of patients scored an excellent or good result, with less than 3% have moderate residual pain. Radiographically, all patients assessed had evidence of stable bony ingrowth. There were nine revisions in all, four stem revisions due to periprosthetic fracture, one secondary to aseptic loosening and one to facilitate a femoral shortening osteotomy. There was one cup revision for psoas tendonitis and one for cup repositioning. This same patient subsequently underwent further revision due to acetabular osteolysis with metallosis and some ceramic wear. Overall, the survival rate of the implants was 96% at 10 years. The retrieved femoral heads showed a median wear rate of 0.2 cubic millimeters per year.

Conclusions: Alumina ceramic on ceramic bearings in cementless primary total hip arthroplasty had been shown to have good survival rate at 10 years with good function, low wear rate and no adverse radiographic changes. The one case of osteolysis may be due to ceramic wear debris or may be due to metal wear debris from the neck to rim impingement.

Background: Squeaking in hip arthroplasty is a phenomenon that was described decades ago, but has only been brought back to attention recently. It occurs predominantly in ceramic on ceramic bearings, and has a reported incidence from less than 1% to 21%. The cause and the implication of squeaking are still unknown and many factors have been suggested to contribute. This study has looked into the patient factors to investigate if any clinical features are associated with an increased risk of squeaking.

Methods: All primary total hip arthroplasties with ceramic on ceramic bearing that were performed at our unit were reviewed and all squeaking hips presented are included in the study. Patient demographics and clinical outcome data were analysed and compared with matched controls from the silent hips.

Results: Between 1997 and 2008, 3375 primary hip arthroplasties in 3182 patients with ceramic on ceramic bearing were performed in our unit. Seventy one hips (2.1%) presented with squeaking on direct questioning and self reporting. Those patients were found to be taller, heavier and younger. They also have a significantly higher post-operative range of hip motion and higher Harris hip score when compared to matched controls. There was no difference in the satisfaction score. Only 4 patients (5.6%) presented with pain as well as squeaking, and 2 (2.8%) resulted in revision surgery for problematic squeaking.

Conclusions: We present the largest series of squeaking primary hip arthroplasties with ceramic on ceramic bearing to date. A number of patient factors were found to be associated with squeaking. The taller, heavier and younger patients with more flexible and functional hips were at a higher risk, presumably because these patients put greater mechanical demands on their hips. Majority of the patients with squeaking are pain free and there is only a small risk of requiring revision surgery.

We investigated factors that were thought to be associated with an increased incidence of squeaking of ceramic-on-ceramic total hip replacements. Between June 1997 and December 2008 the three senior authors implanted 2406 primary total hip replacements with a ceramic-on-ceramic bearing surface. The mean follow-up was 10.6 years. The diagnosis was primary osteoarthritis in each case, and no patient had undergone previous surgery to the hip. We identified 74 squeaking hips (73 patients) giving an incidence of 3.1% at a mean follow-up of 9.5 years (4.1 to 13.3).

Taller, heavier and younger patients were significantly more likely to have hips that squeaked. Squeaking hips had a significantly higher range of post-operative internal (p = 0.001) and external rotation (p = 0.003) compared with silent hips. Patients with squeaking hips had significantly higher activity levels (p = 0.009). A squeaking hip was not associated with a significant difference in patient satisfaction (p = 0.24) or Harris hip score (p = 0.34). Four implant position factors enabled good prediction of squeaking. These were high acetabular component inclination, high femoral offset, lateralisation of the hip centre and either high or low acetabular component anteversion.

This is the largest study to date to examine patient factors and implant position factors that predispose to squeaking of a ceramic-on-ceramic hip. The results suggest that factors which increase the mechanical forces across the hip joint and factors which increase the risk of neck-to-rim impingement, and therefore edge-loading, are those that predispose to squeaking.

Purpose: Pigmented Villonodular Synovitis (PVNS) is an uncommon presentation characterised by hyperplastic synovium, bloody effusions and bone erosions. Incompletely resected localised and diffuse lesions have a high recurrence rate. The management of recurrent lesions depends on the expertise of the surgeon and severity of the lesion. The imaging characteristics of PVNS and experience of British knee surgeons in managing these lesions is presented in our study.

Methods: A postal questionnaire was sent to 100 knee surgeons of the British Association of Surgeons of the Knee (BASK) with questions relating to their experience in managing localised and recurrent PVNS. The options included either arthroscopic or open synovectomy with or without radiotherapy, radical excision or referral.

Results: 74 responses were included in the study. 73 out of the total cohort of 74 surgeons (98.7%) had seen less than 5 presentations in their career.

Localised lesions were treated primarily by arthroscopic synovectomy [N=58(78.4%)] or open synovectomy [N=12(16.2%)] with radiotherapy being utilised in 4 lesions (5.4%).

For local recurrence the management was arthroscopic [N=26(35.1%)] and open [N= 19(25.7%)] synovectomy. Radiotherapy was used in 18 (24.3%) of patients with localised recurrence and 8 (10.8%) of were referred to specialist units.

Infiltrating lesions were treated with open synovectomy and radiotherapy [N=22(29.7%)] and 20 cases [27.02%] were referred to specialist units.

Imaging of PVNS and Conclusions: The role of imaging is invaluable in early diagnosis and treatment due to limited experience in managing such presentations. Routine radiography and Computerised Axial Tomography (CT scan) often demonstrate non-marginal pressure erosions with sclerotic margins as well as nodular soft tissue masses. Sonography shows non-specific focal or nodular synovial thickening with increased flow on colour doppler. Magnetic Resonance imaging characteristics of PVNS are nodular, synovial masses which are low signal on T1-weighted and T2-weighted imaging.

Granular Cell Tumours are rare mesenchymal soft tissue tumours that arise throughout the body and are believed to be of neural origin. They often present as an asymptomatic slow-growing benign solitary lesion but may be multifocal. One to two percent of cases are malignant and can metastasise.

Described series in the literature are sparse. We examined our database and identified eleven cases in ten patients treated surgically and followed-up for a period of over six years (May 2002 to January 2009) in our regional bone and soft tissue tumour centre.

Five tumours were located in the lower limb, four in the upper limb and two in the axial skeleton. Mean patient age was 31.2 years (range 8 to 55 years). Excision was complete in one case, marginal in five cases and intra-lesional in five cases. No specimens showed evidence of malignancy. No patients required postoperative adjuvant treatment. Mean follow-up was 19.3 months (range 1 to 37 months), with no cases of local recurrence. One case was multi-focal.

Histopathological examination revealed the classical features of granular cell tumour in all cases. Typically, tumour cells were diffusely and strongly positive for S100 protein by immunohistochemistry, whereas the other markers tested were negative.

We believe this case series to be the largest of its type in patients presenting to an orthopaedic soft tissue tumour unit. We present our findings and correlate it with findings of other series in the literature.

Performing Bilateral Knee replacements simultaneously is a controversial issue with proponents on both sides of the argument. The advantages of simultaneous arthroplasties include the administration of a single anaesthetic, reduced hospital stay and consequent reduced costs. Reuben et al (J. Arthroplasty, 1998) reported a 36% reduction in hospital costs. Patients also have a quicker return to function and Leonard et al (J Arthroplasty 2003) reported a high patient satisfaction rate of 95%.

The primary disadvantages noted in previous studies include an increase in peri operative complications–both cardiac and pulmonary. An increase in mortality figures is perhaps the most serious complication recorded in some studies. Ritter etal (Clin. Orthop. 1997) reported a 30 day mortality rate of 0.99% in bilateral simultaneous TKA as compared to 0.3% in patients who underwent a staged procedure.

Our study comprised a total of 202 patients who underwent bilateral simultaneous total knee replacements at a District General Hospital in Harlow. Harlow is one of the centres involved in the multi centric trials for the PFC Sigma Knee System and is perhaps the only centre in the UK where bilateral simultaneous procedures are carried out in significant numbers. There were 103 males and 99 females. 12 of the patients had Rheumatoid arthritis. 45% of the patients were in the 71–80 years age group, 26% in the 61–70 years age group. The average age across the entire group was 71.3 years. 35% of patients had a BMI of 25–30, 23% a BMI of 30–35, while less than 5% had a BMI of greater than 40. Most patients (44%) were ASA grade 2. The 3 most common co morbidities included hypertension(85%), coronary artery disease(25%) and diabetes mellitus (12%). 90% of the patients had the procedure performed under a General Anaesthetic and Epidural. Tourniquet time ranged from 55–159 minutes. (average 96 minutes). The patella was resurfaced in all patients. Post operatively the average drain collection was 1200 mls(range 7002600mls). Average pre op Hb was 13.8 g/dl, the post op average being 9.7 g/dl. 71% of patients required blood transfusion after surgery (average 2.8 units). Average hospital stay was 12.4 days (range 5–38 days). 6 patients required HDU admission.

Complications: None in 60%; there were 3 deaths in the first 30 days(1.5%), 2 cases of pulmonary embolism(1%); 6 cases of Myocardial Infarction (3%). There were 14 superficial wound infections and 10 patients required wound washouts. An MUA was performed on 8 knees. 2 patients had Revision Knee replacements for infection.

These figures are comparable to those in published literature. We have found Bilateral simultaneous Total Knee replacements to be a safe procedure with quick return to function.

The outcome of total hip replacement (THR) is potentially affected by the body mass index (BMI) of the patient. We studied the outcome of 2026 consecutive primary cementless THRs performed for osteoarthritis. The mean follow-up was 6.3 years (0 to 11.71) and no patient was lost to follow-up for survival analysis. The patients were divided into two groups according to their BMI as follows: non-obese (BMI < 30 kg/m²) and obese (BMI ≥ 30 kg/m²).

The obese patient undergoing surgery was found to be significantly younger (p < 0.001). The log-rank test for equality of survival showed no difference in the mid-term survival (p = 0.552) with an estimated survival at 11 years of 95.2% (95% CI 92.5 to 98.0) in the non-obese and 96.7% (95% CI 94.9 to 98.5) in the obese groups. The clinical and radiological outcome was determined in a case-matched study performed on 134 obese individuals closely matched with 134 non-obese controls. The non-obese group was found to have a significantly higher post-operative Harris hip score (p < 0.001) and an increased range of movement, but overall satisfaction with surgery was comparable with that of the obese patients. Radiological analysis of the acetabular and femoral components showed no significant differences with regard to radiolucent lines, osteolysis, ingrowth of the femoral component, the acetabular inclination angle or alignment of the femoral component. Our results suggest that the survival of cementless THR is not adversely affected by obesity. Obese patients can therefore be counselled that despite a lower clinical score, they should expect to be satisfied with the result of their THR with a mid-term survival rate equivalent to that of non-obese patients.

Introduction: Trabecular Metal (Tantalum) has been successfully used in Neurosurgery for many years. Acetabular components have only been available in the UK since 2004. The metal’s properties of porosity and a high friction coefficient are attractive, particularly in complex primary and revision hip arthroplasty when surgical challenges include abnormal, deficient or limited bone.

Methods: Two year results of 110 consecutive acetabular reconstructions are presented. The age range was between 27 and 95 years with a predominance of females. The indication in 75 primary hip replacements included, Destructive Osteoarthritis, Dysplasia, Rheumatoid Arthritis, Paget’s and AVN. 35 revisions were performed either two-component or single acetabular exchanges.

Clinical results have been obtained using the Merle d’Aubigne score and bone deficiencies were classified according to the AAOS system.

Results: There have been no failures and radiologically, serial X-rays demonstrate osseo-integration at an early stage.

We have had no cases of deep infection but there have been 3 femoral peri-prosthetic fractures, (1 late) and 2 dislocations.

All patients have been allowed early weight bearing and those patients with over 12 months follow up have an improved Merle d’Aubigne score.

Discussion: The biomechanical properties of Trabecular metal and a modular design permit a press fit technique supplemented by dome screws combined with the possibility of using varying sizes of liner to minimise dislocation or to retain well fixed femoral stems in revision surgery.

The ease of use of the implant has now led to us largely abandoning other reconstructive techniques such as impaction allo-grafting or cages in revision or complex primary hip surgery.

We consider Trabecular metal to be a major advance in acetabular reconstruction on the basis of our initial experience

Pelvic and acetabular surgery may be associated with significant blood loss because of the vascularity and anatomy of the pelvis. Concerns continue in relation to blood transfusion because of the potential for disease transmission and because of the increasing cost of providing safe blood products. The purpose of this study was to examine in a retrospective fashion the blood transfusion requirements in a consecutive series of patients undergoing peri-acetabular osteotomy for hip dysplasia.

Surgery was performed under general anaesthesia with an epidural in place in the majority of cases. A cell saver was not used and no pre operative autologous blood donation was performed. In seven cases one unit of blood was drawn off immediately prior to the operation in the anaesthetic room and re-infused towards the end of the operation. This practice was discontinued when one of these units clotted and could not be re-infused. A post-operative transfusion policy was adopted where an haemoglobin (Hb) concentration of < 7.5 g/dl was an indication for transfusion.

There were 19 females and 2 males. The average age was 26.6 (range 14 – 40). The average duration of surgery was 233mins (range 180 – 285min). Pre-operatively the average Hb concentration was 13.68 g/dl (range 12.3 – 16.2 g/dl). Overall 16 patients did not require any cross-matched transfusion. Two patients received one unit of blood and three received two units. If the transfusion policy had been correctly followed, 4 of these patients would not have received cross-matched blood. The average post-op Hb in those not receiving transfusion was 8.6 g/dl (range 7.3 – 9.9 g/dl).

This study shows that it is possible to safely perform peri-acetabular osteotomies in most cases without blood transfusion which is important in this group of patients who are generally young and female.

Aims: To compare the in vivo wear rates of the polyethylene inserts of different thicknesses in Freeman-Samuelson (F/S) total knee arthroplasties. Methods: Radiographs of 17 patients with F/S modular prostheses and 6mm thick inserts, 19 patients with 8mm inserts, and 6 patients with F/S1000 (more conformed medial femoral condyle) with 8mm inserts were studied. The distance (polyethylene thickness) between femoral and tibial components was measured from A-P radiographs at 6 months, 3 years and 5 years with correction for magnification and antero-posterior tilting of the tibial tray. Wear rates were calculated. Comparisons were made between the medial and lateral sides of the inserts, between the different thicknesses and between the two types of prostheses. Results: The difference in the wear rate between the medial and lateral side in the 3 groups of polyethylene inserts was shown to be 0.229, 0.054, and −0.044 mm/yr (p> 0.2 in all 3 groups). Between the two thicknesses in the F/SM group, the 6mm group had a higher wear rate than the 8mm group (diff = 0.072 mm/yr, p< 0.05) over 5 years, with the majority of wear occurring in the first 3 years (Diff = 0.098mm/yr, p< 0.05). Between the two types of prostheses used, the wear rate over 5 years was shown to be 0.006mm/yr (p> 0.5). Conclusions: The study showed that the 6mm polyethylene components had a significantly higher rate of wear than the 8mm ones, but there was no significant difference shown between the medial and lateral sides of the inserts and two versions of the prosthesis.