Introduction

The ideal method of fixation for femoral components in total hip arthroplasty (THA) is unknown. While good results have been reported for cemented and uncemented components, there is relatively little published prospective data with twenty years or more of follow up.

Results of the Furlong femoral component have been presented at an average of 17 years follow up. We have extended this follow up period to an average of 22.5 years with a minimum of 22 years and a maximum of 25 years.

Background

There is increasing interest in the use of Total Hip Replacement (THR) for reconstruction in patients who have suffered displaced intracapsular hip fractures. Patient selection is important for good outcomes but criteria have only recently been clearly defined in the form of national guidelines. This study aims to investigate patient reported outcomes and satisfaction after Total Hip Replacement (THR) undertaken for displaced hip fractures and to compare these with a matched cohort of patients undergoing contemporaneous THR for osteoarthritis in order to assess the safety and effectiveness of national clinical guidelines.

In this review, we present the data of one of the largest non-designer, mid- to long-term follow ups of the AGC.

We present a total of 1538 AGC knees during a 15 year period, of which 902 were followed up by postal or telephone questionnaire focused on Oxford Knee Scores, Visual analogues of function and pain and survival analyses performed. Mean length of follow up was 10.4 years.

85.7% of patients had an Oxford knee score of between 0 and 40, with 71.2% scoring between 0–30.

65.6% of patients responded with a Visual Analogue Score (VAS) of 0 or 1 at rest (minimum pain 0) and 53.9% reporting VA scores of 0 or 1 while walking.

87.5% of patients reported Excellent or good functional reports at final follow up and 90.3% reporting excellent or good pain control compared to per-operative levels.

Survival analysis confirms excellent survivorship.

This large cohort and multi-surgeon trial reproduces the excellent results as demonstrated by the designer centre (Ritter et al.). Mid to long term outcome sows excellent function and analgesia. Complication rates are low and the necessity for revision remains low.

Introduction

Deep vein thrombosis(DVT) and pulmonary embolism(PE) are well-recognised complications following lower limb arthroplasty (Cohen et al, 2001). The National Institute for Clinical Excellence and British Orthopaedic Association recommend the use of both mechanical and chemical prophylaxis. At our institute regimens have changed reflecting new developments in the use of thombo-prophylaxis. Our aim was to assess the efficacy of these methods in preventing complications.

A reduced range of movement post total knee replacement (TKR) surgery is a well recognised problem. Manipulation under anaesthesia (MUA) is a commonly performed procedure in the stiff post operative TKR. Long term results have been variable in the literature.

We prospectively followed up 48 patients since 1996 from one centre, over an average of 7.5 years, (range 1 to 10 years) and report on the long term results.

The mean time to MUA post TKR was 12.3 weeks (range 3 to 48). Pre MUA, the mean flexion was 53°. The mean immediate passive flexion post MUA was 97°, an improvement of 44° (Range 10° to 90°, CI < 0.05). By one year, the mean flexion was 87°, improvement of 34°, (range −15° to 70°, CI< 0.05). At ten years the mean flexion was 86°.

We found no difference between those knees manipulated before or after 12 weeks. In addition there was no difference found in those knees which had a pre TKR flexion of greater or less than 90°. There were no complications as a result of MUA. However, one patient was eventually revised at two years secondary to low grade infection.

Our findings show that MUA is safe and effective method at improving the range of motion in a stiff post operative TKR. The improvement is maintained in the long term irrespective of time to MUA and range of motion pre TKR

Purpose of Study

In this review, we present the data of one of the largest non-designer, mid- to long-term follow-ups of the AGC carried out by surgeons of differing grades and sub-specialty.

Aims

To compare a randomised group of patients undergoing UKA to investigate the advantages of the minimal invasive approach in the early post-operative stage.

Introduction

Hydroxyapatite (HA) coated femoral stems require a press fit for initial stability prior to osteointegration occurring. However this technique can lead to perioperative femoral fracture.

The most common indication for knee arthrodesis is pain and instability in an unreconstructable knee following an infected knee arthroplasty. In this study, we compare the use of the Mayday arthrodesis nail (Ortho-dynamics, Christchurch, UK) versus external fixation, Orthofix (Berkshire UK) and Stryker Hoffman II (County Cork, Ireland).

All patients in this study underwent arthrodesis between 1995 and 2006 at Conquest Hospital, Hastings. In group A, 11 patients underwent arthrodesis with a Mayday nail. In all cases, the indications were infected total knee replacements (TKR). Three of these patients previously had failed attempts at arthrodesis with external fixation devices. In group B, seven patients underwent arthrodesis using external fixation. In six patients, the indication was infected TKRs. Results were reviewed retrospectively, with union assessed both clinically and radiologically.

The mean inpatient stay for the Mayday nail group was 23 days (range 8 – 45 days) compared with 76 days (range 34 – 122) for the external fixation group (p< 0.01, CI 95). Ten patients in group A went on to confirmed primary arthrodesis. One patient underwent revision arthrodesis with a Mayday nail and subsequently united. In group B only two patients achieved union. The rate of union was significantly greater in the Mayday nail group than the external fixation group (91% vs 29%, p< 0.01). Of those patients that achieved union, there was no difference in the time to fusion between groups.

Our study supported the existing literature and found that the Mayday nail appeared more effective than monoaxial external fixators for arthrodesis in the management of infected total knee replacements.

Introduction: Acetabular loosening can limit long-term success of total hip replacement. There are at least 62 different prosthesis designs available in the UK, many of which have no long term results. Revision surgery is expensive, challenging and potentially dangerous. There is still currently debate about the best method of acetabular fixation, in particular, regarding the use of press fit devices in elderly osteoporotic bone. Our study aims to test the null hypothesis that there is no significant difference in outcome between cemented and non-cemented acetabular fixation in this group of patients.

Methods: Patients over 72 years of age were prospectively randomised to receive either a cemented Exeter cup or a HA coated press fit cementless cup. Both groups received a cemented Exeter stem. The patients were assessed pre-operatively and reviewed at 6 weeks, 6 months and yearly in a research clinic, by an independent observer. Outcome measures were the Merle D’Aubignon Postel, Oxford Hip and Visual analogue pain scores. The implants were also assessed radiographically and all complications were recorded.

Results: To date 151 patients have been recruited into the trial. 2 year data is available for 69 patients. There were no differences in satisfaction, pain or hip scores between the groups.

There have been no major surgical complications. In particular, there have been no failures of acetabular fixation, dislocations or deep infections.

Discussion: There have been no failures in either group. Although there is insufficient data at this stage to reject our null hypothesis, there is no early evidence for concern in using cementless cups in elderly patients.

AIMS: To compare a randomised group of patients undergoing UKA to investigate the advantages of the minimal invasive approach in the early post-operative stage.

METHODS & RESULTS: 100 patients on the waiting list for UKA were recruited into the trial. Patients were randomised into 2 groups: Group 1 – longitudinal skin incision with dislocation of the patella, Group 2 – the minimally invasive approach. Standard milestones were recorded post-operatively: time to achieve IRQ, independent stair climbing and to discharge. Additionally, patients were scored with the AKSS and Oxford knee questionnaire pre-operatively, at 6 weeks, 6 months and 1 year.

No significant differences were found between the 2 groups in the measured parameters.

CONCLUSION: To our knowledge, there has been no previous randomised trial to investigate the results of less invasive surgery for UKA. We have been unable to demonstrate a significant advantage of this approach. With the continued drive for early return to function, some centres incorporate a 24hr accelerated discharge protocol. The less invasive approach may make this more achievable. We recommend however that the surgical procedure and implant position must not be compromised for the benefit of rapid discharge to the deficit of long term results.

The 98 % 10-year survivorship of cemented AGC TKR is regarded as gold standard.(1) The authors attributed their excellent results to the flat-on-flat design and compression-moulded polyethylene.

The aim of this trial is to determine if the type of fixation also influences outcome.

Participants were randomly allocated to either a cemented or cementless hydroxyapatite-coated AGC prosthesis. All patients were assessed with the Hospital for Special Surgery Score (HSS) and radiographs pre- and post-operatively at six weeks, six months and annually.

223 knees were studied with a mean follow-up of 53.4 months (max.10 years).

There were no significant differences between the two groups in post-operative HSS scores or in improvement of HSS scores. There has been no observable migration in either group. There has been 1 case requiring revision from the HAC group and 2 patellar buttons were revised following traumatic separation.

The early results are equally good for both groups with no significant difference in outcome or complication rate between cemented and HA coated fixation.

Introduction and Aims: The use of porous coated femoral stems in revision hip arthroplasty has been associated with a high rate of complications including femoral fracture, femoral perforation and eccentric reaming. The purpose is to determine if using a distally slotted-fluted femoral stem is associated with lower incidence of the above three intra-operative complications.

Method: The intra-operative complications of 175 cementless revision total hip arthropasties (THA) using a distally slotted-fluted femoral stem were reviewed. Three categories of complications were recorded: femoral fracture, femoral perforation and eccentric reaming. Radiographic evaluation was based on standard antero-posterior and lateral views of the hip joint performed in the intra-operative or immediate post-operative period. Statistical analysis for factors associated with complications was performed using the chi-square test.

Results: Intra-operative complications occurred in 16 patients (9.1%). There was no statistically significant association between complication rate and type of surgical approach, stem length, stem diameter, or host bone quality. The complication rate was significantly lower than the 44% total complication rate previously reported utilising a long, solid, extensively coated revision stem without a slot or flute (p< .01). These results are consistent with laboratory testing, which revealed significantly lower bone strains at the isthmus when inserting a long cementless revision stem with a slot and flute compared to a solid fully coated stem of identical geometry.

Conclusion: The use of a distally slotted fluted porous coated femoral stem in revision hip arthroplasty results in a dramatically lower complication rate compared to rates previously reported for solid porous stems. These results strongly support the continued use of such a prosthesis for revision THA.

Introduction and Aims A randomised controlled trial (RCT) and a multi-centre unilateral cohort study were performed as part of the stepwise introduction of a new mobile bearing knee. The aim was to ensure that outcome for the new device was at least as good as that for an established fixed bearing device. This paper presents three year follow up of the published one year results. Instability and prevalence of “clicking” from the joint were examined in detail.

Method 1. A multi-centre RCT of patients undergoing bilateral knee replacement compared functional outcome between two different prostheses, the new mobile bearing device (TMK) and an established fixed bearing device (AGC). 2. A separate multi-centre cohort of 166 patients who had undergone a unilateral mobile bearing procedure at least six months previously was used to assess complication rate and corroborate any findings from the bilateral trial. Outcome measures included Oxford Knee Scores, American Knee Society ratings and complication rate.

Results The bilateral trial revealed no significant differences in outcome between the two devices. Revision rate for all (199) mobile bearing knees was less than 2%. The mean Oxford Knee Score for outcome for all mobile bearing knees was 37.1 ± 10.1. About 7% of patients reported instability. Clicking was more common in the TMK (48%) than in the AGC (30%) and was reported as a problem in 16% of TMK’s in the cohort study. However, clicking was unrelated to outcome score in both studies.

Conclusion At three years, the mobile bearing device was as good as the fixed bearing device. There was a relatively high prevalence of “clicking” in the TMK but the cause remains unclear. Furthermore, the symptom was not associated with poor functional outcome. The bilateral RCT and cohort study allows assessment of function and potential problems. It provides rigourous scientific justification for the introduction and early assessment of new implants.

Introduction Recent publications have confirmed that as many as one in four retrieved femoral heads can be significantly contaminated with potential pathogens. Reports from the Centre for Disease Control in Atlanta, Georgia have described fatal outcomes from the unwanted transmission of bacterial disease with inadequately processed allograft materials. Surgeons requesting non terminally sterilised bone refer to theoretical biological and biomechanical deleterious effects of gamma irradiation. This study examines the accuracy of those claims.

Methods We have investigated the effects of varying levels of gamma irradiation (0kG, 15kG and 25kG) on the biological competence of morsellised allograft bone and its associated biomechanical impaction qualities. The biological study has used an in vivo model (nude rat) to quantify the effects of gamma irradiation on osteoinduction and osteoconduction. An in vitro impaction routine has been used to measure compaction, impaction and stiffness in the allograft product.

Results There were no statistical differences in the biomechanical or biological properties of the 0kG and 15kG specimens (P< 0.05). Gamma irradiation at the 25kG level resulted in an allograft product of higher biomechanical stiffness, unchanged osteoinductivity and slightly lower osteoconductivity (P< 0.05).

Conclusion Terminal gamma irradiation of 15kG reduces the risk of bacterial transmission with allograft products. It does not alter the efficacy of the allograft at biological and biomechanical levels. Gamma irradiation represents the mainstay of sterilisation of musculoskeletal allograft materials. Australian practices appear to be leading an international trend.

In relation to the conduct of this study, one or more the authors have received, or are likely to receive direct material benefits.

Aims: Anterior knee pain is a common complaint of mixed aetiology, and in many cases no demonstrable cause is identified. For patients with persistant anterior knee pain, tibial tubercle transfer (TTT) can be a surgical option. The aim of this study is to assess the effectiveness of TTT for chronic anterior knee pain resistant to conservative treatment. Method: All patients with arthroscopically proven Chondromalacia patellae (CMP) without clinical evidence of patella instability, who have failed to respond to conservative treatment such as physiotherapy were included in the trial. They underwent TTT with a modified Fulkerson technique and then routine post-operative care with a cricket pad splint for 2–4 weeks. Pre and post-operative scores were obtained using a Kujala patello-femoral score, a visual analogue score for pain and a patient satisfaction score. The Outerbridge grading was used to score the severity of CMP at arthroscopy. Results: There were 50 TTT’s followed up (7 staged bilaterals) with a mean follow up of 32.4 months (5–88 months). There were significant improvement in the pre-operative and post-operative Kujala (p> 0.001) and visual analogue pain scores (p> 0.001). Of the 50 TTT’s 70% had an excellent or good result and 30% a fair or poor result. Moreover 76% claimed that they would have the same operation again for their condition. There was no significant correlation between Outerbridge grading and post-operative outcome. Complications include late anterior knee pain (10 cases), superficial wound infection (1 case), non-union of osteotomy (1 case) and tuberosity fracture (1 case). Conclusion: Anteromedial tibial tubercle transfer is a reliable and effective treatment for peristant anterior knee pain.

Aims: To determine the optimum hydroxyapatite-coating pattern of the femoral component in cement-less hip arthroplasty. Methods: Between January 1996 and May 1997, the þrst 65 patients (73 hips) of a single center prospective trial were randomised to receive a proximally coated Osteonics or a fully coated JRI Furlong stem. 30 Osteonics and 43 JRI stems were implanted. Clinical assessment was carried out using the modiþed Merle DñAubigne and Postel (MDP) system and the visual analogue scale (VAS). Radiological evaluation included measurement of subsidence, bone resorbtion, pedestal formation and implant-bone interface assessment. All live patients were reviewed. The average follow up was 50.3 months in the JRI group and 51.8 months in the Osteonics group. Results: There was one cup revision in both groups for aseptic loosening and one excision arthroplasty in the JRI group for sepsis. Clinical evaluation revealed an MDP of 16.3 (8–18) and a VAS of 0.55 (0–7) for the JRI group. The MDP for the Osteonics group was 16.31 (8–18) and the VAS 0.62 (0–4). Radiological evaluation revealed resorbtion in zone 7A in 16 of the JRI hips and 5 of the Osteonics. There was a reactive line around the distal part of the Osteonics stem in 17 patients, which was not correlated with symptoms. Conclusion: Both hips performed well. There was no difference in revision rate for loosening (p> 0.84). Clinical evaluation showed no signiþcant difference in outcome (p> 0.83). Radiology revealed different patterns, which did not represent a clinical importance at this stage.

Aims: The 98% 10 year survivorship of the cemented AGC TKR is regarded as gold standard.(1) The authors attributed their excellent results to the flat on flat design and the compression moulded polyethylene rather than the cement. The aim of this trial is to determine if the type of fixation also influences outcome. Method: Participants were randomly allocated to either a cemented or cementless hydroxyapatite coated AGC prosthesis. All patients were assessed with the Hospital for Special Surgery Score (HSS) and radiographs pre-operatively and then post-operatively at six weeks, six months, one year and annually. Results: 223 knees were studied with a mean follow up of 39 months (max 8 years) Both groups were well matched for age and sex. There were no significant differences between the two groups in post-operative HSS scores or in improvement of HSS scores. There has been no observable migration in either group. There were 15 radiolucenies (< 2mm) in the cemented and 1 in the HA group. A common finding in the HAC group was a radiodense line around the uncoated stem of the tibial prosthesis which is of no clinical significance. There has been 1 case requiring revision, which was from the HAC group. In addition 2 patella buttons were revised following traumatic separation. Conclusion: The early results are equally good for both groups with no significant difference in outcome or complication rate between cemented and HA coated fixation.

The aim of this study was to assess the outcome of patients who underwent ElmslieTrillat antero-medial tibial tubercle transfer for treatment of persistent symptomatic anterior knee pain due to chondromalacia patellae.

We performed a prospective analysis of 23 patients who underwent Elmslie-Trillat antero-medial tibial tubercle transfers over a five year period for chronic anterior knee pain and an arthroscopic diagnosis of chondromalacia patellae. All patients who presented with anterior knee pain underwent an initial period of physiotherapy and all patients whose symptoms persisted following physiotherapy underwent arthroscopic assessment. Patients who continued to experience debilitating symptoms despite this initial treatment and who also had a diagnosis of chondromalacia patellae from arthroscopic assessment were listed for an Elmslie-Trillat tibial tubercle anteromedialisation. Patients who gave a history of instability or dislocation were excluded. The average age of patients undergoing surgery was 34 years (21–48 years) and the average time between arthroscopic diagnosis and surgery was 14 months. All patients who underwent surgery had pre and post operative KuJala patellofemoral scoring. The average pre-operative score was 54 (30–78) and post operative score 76 (46–100). The average post operative assessment was 25 months (6–62 months). Twenty one patients had improved post operative scores with one having a worse score and one score remaining unchanged following surgery. Nineteen patients felt that their symptoms had improved, three felt that there had been no change and one felt that they were worse after surgery. When asked if the improvement in symptoms had been worthwhile nineteen stated that they would undergo surgery again if in the same situation and four stated that they would not.

The treatment of symptomatic chondromalacia patellae remains a challenge. Although a more selective approach to individuals with anterior knee pain is widely advocated in the literature this study demonstrates that good results can still be achieved in patients treated empirically with a tibial tubercle anteromedialisation.

Clinical implantation represents the ultimate experiment of any component and often demonstrates areas of strengths and weaknesses not predicted from in vitro testing. Mobile bearing knees incorporate an additional articulating interface between the flat distal PE insert and a highly polished metal tibial tray. This can allow the proximal interface to retain high conformity whilst leading to reduced stresses at the bone – prosthesis interface by permitting complex distal interface compensatory motion to occur (rotation and/or translation). Retrieval reports on many of the new generation of mobile bearing implants remains scarce. This study presented a retrieval analysis of 9 mobile bearing inserts that had be in situ for less than 24 months.

Nine cemented mobile bearing implants (6 AP Glide, 1 LCS, 1 MBK and 1TRAK) were received into our Implant Retrieval Program. The femoral component, tibial tray and PE insert were macroscopically examined under a stereo-zoom microscope for evidence of damage. The PE inserts were graded for wear based on optical and SEM assessments. The proximal and distal surfaces of the PE inserts were subsequently assessed for surface roughness following ISO 97 (Ra and Rp) using a Surfanalyzer 5400 (Federal Products, Providence, RI). Virgin, unused PE inserts were analysed and served as a comparison to the retrieved implants.

Time in situ time for these implants ranged from 6 months to 24 months (mean 18.6). The implants were revised for instability and pain (AP glide) or dislocation (TRAK). Damage to the femoral components, in general, was minimal with some evidence of a transfer film of PE. The proximal surface of the tibial trays presented evidence of PE transfer as well as some scratches but in general were intact. The proximal PE and distal PE articulating surfaces demonstrated significant areas of damage due to third body wear which was identified on EDAX to be PMMA. Areas of burnishing were also present at the proximal and distal interface. The damage, in part, correlated with the complex kinematics of each design.