The drive in contemporary medicine is improved utilisation of scarce resources and a faster turn around of patients, with patients seeking faster recovery from surgery. Delaying factors in discharge from hospital following total knee replacement surgery include the time taken to get active extension and a straight leg raise following surgery. A retrospective case matched study of 20 patients shows that reducing the length of incision into the quadriceps tendon, therefore sparing the quadriceps mechanism speeds the post operative recovery significantly. Reducing the average time to discharge from 9.6 days in the control group to 3.2 days in the quadriceps-sparing group. All but one patient had an ASA grade of 2 with no significant co-morbidity in either group. No patient in either group suffered a post-operative medical event precipitating a delayed discharge. The criteria for discharge were the same in both groups.

Although hydroxyapatite (HA) coating is known to enhance fixation in THR, its role in the fixation of Total Knee Replacements is less well appreciated. This study was performed to assess the medium-term results of an HA-coated TKR. Between August 1992 and 1998 all patients requiring a primary TKR were treated with a hydroxyapatite-coated, PCL-retaining prosthesis implanted by the senior author. The HA coating used was 70 microns thick with 75% crystallinity and 20% porosity. It is deposited on a beaded heat-sintered surface. A combined Hospital for Special Surgery and Knee Society Score was recorded pre-operatively and at three, six, 12, 24 and 60 months post-operatively. Fluoroscopically-controlled interface views were performed on the first 161 knees immediately post-operatively and repeated 24 months postoperatively. Six hundred and ninety two patients (Male:Female 335:357) with a mean age of 68 years (31–88 years) underwent 1 000 TKR mainly for OA (93%) and inflammatory arthropathies (RA 3%, psoriasis 1%). The mean follow up was 75 months (40–115). There were 461 unilateral (R:L 256:205) and 539 bilateral replacements (462 simultaneous and 77 staged). The pre-operative knee score was 95/200, ROM 6–115 degrees and at latest review was 182/200, ROM 1–113 degrees. Forty four patients have died (mean age 73 years, range 54 to 88). There have been 14 deep infections (1.4%), 22 proven pulmonary emboli (2.2%) and five periprosthetic fractures (0.5%). Six revisions have been performed. Visible gaps between bone and implant were present in 91% of femora and 58% of tibiae initially and in 6% of femora and 8% of tibiae at two years on interface views. There have been no cases of clinical loosening. Currently, this study comprises the largest known series of HA-coated total knee replacements. These results demonstrate that HA appears to enhance fixation of uncemented knee prostheses which maintain good clinical outcomes

Purpose of Study: To assess the safety of our practice of Bilateral Simultaneous Total Knee Replacements. Methods: We retrospectively reviewed 202 patients (404 knees) who underwent bilateral simultaneous total knee replacements using the DePuy PFC Sigma Cruciate Sacrificing Endoprosthesis between January 2000 and January 2006. There were 103 males and 99 females with an average age of 71.3 years (range 41–90 years) included. Indication for surgery was Osteoarthritis in 190 patients and Rheumatoid Arthritis in 12 patients. All patients were reviewed at 6 weeks, 1 year and then yearly post surgery. Results: The average hospital stay was 12.4 days (range 5–38 days) with 6 patients needing HDUadmission post surgery. The average observed blood loss in the drains post surgery was 1200ml (700–2600ml) with an average drop in Haemoglobin of 4.1%, 71% of patients needed a blood transfusion post surgery. Two patients (0.99%) developed a deep vein thrombosis and 2 patients (0.99%) developed a pulmonary embolus.3 (1.48%) deaths were encountered in the immediate post operative period (within 30 days of surgery) and 6 (2.9%) patients suffered a myocardial infarct post surgery.14 (6.9%) patients developed a superficial wound infection of which 10(4.9%) needed a formal washout. 8(3.96%)knees needed a manipulation under anaesthesia for a poor range of movement, and 2(.99%) needed revision total knee replacement for infection. Conclusion: Bilateral simultaneous total knee replacement is a safe procedure in our experience Complication rates observed comparable to published literature on the subject

Purpose: To evaluate the fifteen year survivorship of primary Total Knee Replacements in a single UK health region. Methods: Since the beginning of 1990, and with the agreement of all consultant orthopaedic surgeons in the region, all primary total knee replacements (TKR) performed throughout Trent were recorded prospectively. At the time of operation the surgeon completes a questionnaire, which records demographic, medical and operative details for each patient and implant. In this study we have traced all the patients, who had a primary total knee replacement between 1990 and 1992. We issued a validated, self administered questionnaire to all surviving patients, at a mean of fifteen years post arthroplasty. This questionnaire examines the patient’s level of expectation and satisfaction with their TKR, and also measures their quality of life (using EQ-5D and visual analogue score). Using a similar register, containing information of all revision TKR in the region, we have measured the survivorship of these primary TKR at 10 and 15 years. Results: 4,665 primary TKR were performed on 4,448 patients. At fifteen year follow-up 1,408 patients were alive. The questionnaire response rate was 57.1% (n=912). Of our responders, 87.8% were satisfied with the result of their TKR at 15 years post-arthroplasty, and 82% felt their TKR had met their expectations. Survivorship analysis revealed that 94.7% (+/−0.4%) of implants survive to 10 years, and 92.7% (+/−0.5%) to 15 years. Survivorship was significantly affected by gender of the patient, age at time of primary, and type of prosthesis used. Infection rate at 15 years was 0.9%. Discussion: This is one of the first long term studies of primary TKR, which assesses survivorship of primary TKR beyond 10 years. This study shows that survivorship at 5 and 10 years compares favourably to the results of similar studies from other countries

Background: The risks associated with homologous blood transfusion and the increasing shortage of banked blood have brought the need for blood salvage procedures to the forefront. Post operative blood salvage and autologous blood transfusion have been used though the financial implications of their use has not been assessed in the UK. Methods: We carried out a retrospective study of 98 consecutive unilateral Total Knee Replacements performed in 96/97, under the care of one consultant, of these 55 had non-autologous drains and 43 had autologous drains after surgery. Results:. Mean blood loss (non-autologous system) – 778mls. Mean blood loss ( autologous system) – 633mls. Mean autologous blood reinfused – 360mls. - (autologous drainage system). Mean homologous blood transfused – 179mls. - autologous drainage system). Mean homologous blood transfused – 590mls. - (non autologous drainage system). Total cost for use of autologous drainage system and associated transfusion – 6,226.00. Total cost for use of non-autologous drainage system and associated transfusion – 8,346.00. Conclusions: Autologous drains decreased the need for homologous blood transfusion by 69% and brought about a financial saving of 26%. There were no complications arising from the use of autologous drains. There was less blood loss with the use of autologous drains than non-autologous drains in our study

A prospective, comparative study of two Total Knee Replacement systems was undertaken to compare the traditional end point of revision of the prosthesis with three other end points based on the British Orthopaedic Association Knee Assessment Protocol. These were an unacceptable pain score plus revision, Knee Score of 60% or less plus revision, and a fall to below the preoperative Knee Score plus revision. 182 Knees entered the trial (74 St Leger and 108 Miller-Galante 11 prostheses), and all were assessed for Knee Score pre-operatively. Patients were subsequently assessed for Knee Score at 6 months, 1 year and annually thereafter. 63 implants had reached the five year stage at the time of this study. The results indicate that different patients are designated as ‘failures’ depending on the end point selected, and that different survivorship figures can therefore be calculated with up to 6% variation depending on the end point used. In addition, the most successful prosthesis varies with the end point selected. Although the 95% confidence intervals in this study did not permit us to draw any firm conclusions, we suggest that further investigation into the definition of failure in survivorship analysis is necessary in order to reflect the performance as well as the longevity of Total Knee Replacements

Abstract

By next summer the number of patients in the tranexamic acid group will be much higher, probably around 50–60.

Introduction

Total knee replacements (TKR) are among the commonest operations performed in orthopaedic practice. Literature review showed that 10-30% of patients who underwent TKR needed 1-3 units of blood.

Tranexamic acid (TXA) has been popularised as an effective way to reduce blood loss and subsequent blood transfusion.

Our aim was to investigate the value of TXA in reducing blood loss and blood transfusion after TKR and other clinical outcomes such as deep venous thrombosis (DVT), pulmonary embolism (PE), ischaemic heart diseases and mortality.

Objectives

To investigate the value of tranexamic acid (TA) in reducing blood loss and blood transfusion after TKR and other clinical outcomes such as deep venous thrombosis (DVT), pulmonary embolism (PE), ischaemic heart diseases and mortality.

Bilateral simultaneous total knee replacement surgery remains controversial with arguments for and against its use. Doing sequentially staged TKR's is a safer procedure and may have additional benefits as set out below.

If both knees need to be replaced we have often seen that the symptoms of the contralateral knee improve after the one knee is replaced and that patients wait some time before having the opposite knee replaced.

Polyethylene wear can be an important cause of knee replacement failure.

Six TKRs in young, active patients with excellent Oxford Knee Scores and Knee Society Scores, mean 76 months post knee replacement and 5 control patients, 2 weeks post TKR, were selected. Each patient had weight bearing stereo radiographs of at 0, 15, 30, 45 and 60 degrees of flexion while standing in a calibration grid. These x-rays were analysed using our Radio Stereometric Analysis (RSA) system. The three-dimensional shape of the TKR (manufacturer’s computer aided design model) was matched to the TKR silhouette on the calibrated stereo radiographs for each angle of flexion. The relative positions of the femoral and tibial components in space were then determined and the linear and volumetric penetration was calculated using Matlab software.

The accuracy of the system was found to be 0.3mm (CAD model tolerance 0.25mm). The mean linear wear in the control patients was 0.02mm (range −0.19 to +0.23mm). Average linear penetration in the study group was found to be 0.6 mm at 6 years, giving an overall linear wear rate of 0.1mm/year. Average penetration volume at 76 months was 399mm3. The average volumetric wear rate was 63mm3/year.

It is possible to measure volumetric wear in vivo using RSA. Volumetric wear rate was found to be 63mm3 per year. Studies on retrieved normally functioning hip replacements have shown volumetric wear rates of 35mm3 per year. However, clinical outcomes of knee replacements are comparable to those of hip replacements, suggesting that the knee has a more effective mechanism for dealing with polyethylene wear particles.

During a retrospective case note analysis, a significant difference was found in prosthesis survival, between two cohorts of patients who underwent different total knee replacements. The first cohort included 70 patients who underwent Kinemax Plus total knee replacement, the second cohort included 58 patients who underwent PFC Total Knee replacement. All patients were under the care of one Consultant Orthopaedic Surgeon. Interestingly, the Kinemax Plus cohort was found to have a higher rate of revision compared to the PFC cohort. A detailed comparison was carried out between the two groups to identify any obvious cause for the disparity.

The two cohorts were found to be well matched with respect to age, sex, ASA grade, underlying pathology and operative technique. Median follow up being 6 years and 5 years for the Kinemax Plus and PFC groups respectively.

There were 11 failed prostheses in the Kinemax Plus cohort, 7 undergoing revision with the remaining 4 patients offered revision but unwilling to have surgery. Wear of the polyethylene tibial insert was the most obvious finding at revision, present in six of the seven revisions. 97% of the Kinemax Plus Prostheses were intact at 5 years but by 8 years only 87% were intact. There were no revisions performed in the PFC cohort.

Post-operative x-ray analysis was undertaken to rule out prosthesis malalignment as a cause for the increased failure rate. The coronal alignment of the prostheses (CAK) was calculated and all post operative x-rays were within the normal limits of 4-10 degrees.

Analysis of the explanted Kinemax Plus polyethylene liners was undertaken. In six cases, the polyethylene bearing surfaces displayed severe surface and subsurface delamination. This suggests massive fatigue and fatigue wear. Only one implant showed localised delamination.

These findings suggest the hypothesis of weak polyethylene particle interface strength.

Surgeon’s ability to anticipate the implant size requirements for total knee replacements is important to the success of the procedure. Previously, this has been inconsistently accomplished using plain radiographs. The purpose of this study is to assess the accuracy of digital templating software in predicting the size requirements of the femoral and tibial implants in total knee replacements.

Thirty consecutive PFC (DePuy) total knee replacements were templated preoperatively using digital templating software (TraumaCad, Orthocrat Ltd). The knees were templated by two surgeons working independently using standardised digital AP and lateral radiographs. All films were magnification-calibrated using markers of known size. Postoperatively, the predicted implant size was compared to the actual components selected at the time of surgery.

The size of the femoral prosthesis was accurately selected on the AP view in 53.5% and on the lateral in 66% of cases. The size of the tibial implant was correctly selected on the AP view in 65.5% and on the lateral in 70.5% of cases. The tibial prosthesis was always templated within one size. The femoral prosthesis was predicted within two sizes (93% on AP + 98% on lateral +/− 1 size). There was no correlation with failure of the software to recognise the metal marker and inadequate lateral x-rays.

The lateral x-ray was found to be more reliable than the AP on predicting both the femoral and tibial implants. The tibia was more accurately templated than the femur on average. There was good inter-observer and intra-observer reliability for both prostheses (0.75 – 0.85). Discrepancies in templating may have been due to inaccuracies in placement of the metal marker at the time of x-raying or due to fixed flexion deformities, which may have affected the magnification of the x-ray. Overall, templating using digital software was marginally superior to the standard acetate method.

The Kinemax Plus knee replacement has a reported 10 year survival of around 96%. However we found the survival rate of this implant in our cohort to be 75% at 9 years. No abnormalities were found for clinical and radiological parameters. At reoperation the most striking feature was that of significant ultra-high molecular weight polyethylene (UHMWPE) failure. Oxidative and structural analysis of the polyethylene components was therefore undertaken.

Ten Kinemax Plus tibial inserts were analysed; one was a shelf-aged unused implant, the others were explants. An FTIR analysis of the data showed that oxidation is present in all samples. The degree of oxidation however varied with depth and location. Except for a sharp oxidative peak approximately half way into the sample, the shelf aged samples had a fairly constant level of oxidation. The retrieved implants had an overall higher level of oxidation in both bearing and non-bearing regions. The latter had less of a variation in oxidation which implies that in vivo loading exaggerates the degree of oxidation. In the non-articulating regions oxidation of the explants was found to peak often at the region of about 40% from the bottom surface in all retrieved samples. By contrast, most articulating region had two oxidative peaks; one occurring at approximately 1–1.5mm from the surface, which is consistent with findings on subsurface oxidation, and another occurring about 2–3mm from the bottom surface.

SEM imaging provided evidence for the presence of fusion defects by indicating grain boundaries through-out the explants. This indicates a compromised material which is more susceptible to damage. Fatigue loading of the implant has also been seen to produce a subsurface stress maximum at approximately 1 to 2mm below the articulating surface. It is thought that maximum contact stresses within this region cause Type 1 and Type 2 defects to open or become more pronounced. This in turn will increase the local concentration of oxygenating material as it will be present in these defects and voids where surface areas are greater for oxidative reaction. We therefore hypothesise that these fusion defects are the cause for the early failure of the Kinemax implants.

We aim to explain the significant difference in survivor-ship found between two cohorts of patients who underwent different total knee replacements. The first cohort included 70 patients who underwent Kinemax Plus total knee replacement, the second cohort included 58 patients who underwent PFC Total Knee replacement. All patients were under the care of one Consultant Orthopaedic Surgeon.

Interestingly, the Kinemax Plus cohort was found to have a higher rate of revision as compared to the PFC cohort. A detailed comparison was then carried out between the two groups to identify any obvious cause for the disparity.

The two cohorts were found to be well matched with respect to age, sex, ASA grade, underlying pathology and operative technique. Median follow up being 6 years and 5 years for the Kinemax and PFC groups respectively. There were 11 failed prostheses in the kinemax cohort, 7 undergoing revision with the remaining 4 patients offered revision but unwilling have surgery. Wear of the polyethylene tibial insert was the most obvious finding at revision, present in six out of the 7 revisions. 97% of the Kinemax Plus Prostheses were intact at 5 years but by 8 years only 87% were intact.

There were no revisions performed in the PFC cohort.

Post operative x-ray analysis was undertaken to rule out prosthesis misalignment as a cause for the increased failure rate. The coronal alignment of the prostheses (CAK) was calculated and all post operative x-rays were within the normal limits of 4–10 degrees.

Analysis of the explanted Kinemax Plus polyethylene liners was undertaken. In six cases, the polyethylene bearing surfaces displayed severe surface and subsurface delamination at both medial and lateral sides. This suggests massive fatigue and fatigue wear. Only one inplant showed localised delamination. The surface characterisation suggests the hypothesis of weak UHMWPE particle interface strength.

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.

Three hundred and fifty-eight Tri Con 2 total knee replacements were done between 1987 and 1993. There were three versions of the femoral component, smooth for cement, porous coated and HA coated. Fifty-nine died or were lost to follow-up within two years leaving 229 cases with a follow-up of between 2 and 17 years. Eighteen were cemented, 162 porous coated and 51 HA coated. No porous or cemented femoral components were revised. Three (5.9) HA components were. One was revised at 2 years for unexplained pain. Revision did not help. In 2 cases the tibia loosened. The HA femoral component was tight. There was significant femoral osteolysis. It was possible to knock off the femoral component fairly easily. Virtually no HA remained on the components. There was significant 3-body wear of the polyethylene.

The conclusions are that the advantage of an HA coating is that well-fixed femoral component can be knocked off with a simple application of force. This can never be done with a well fixed porous component. The disadvantage is that HA fixation does not seal against osteolysis. The incidence of 3-body wear is possibly increased and HA coating may have a finite life expectancy.

As allergic reactions to implant wear are gaining more attention [4], the incorporation of ceramic materials to device design appears to be a promising development. In particular, ceramic femoral components of total knee replacements have been designed to produce less wear under standard [1] and adverse [5] implant conditions.

Whereas the wear reduction effect of ceramics is generally accepted for hip implants, the corresponding effect for knee implants is not proven. Ezzet et al. reported a wear reduction of 42% for standard wear conditions [2] and of 55% for adverse wear conditions [3] when compared to a geometrically identical CoCr femoral component. In contrast to these findings, an analysis of the EndoLab® database has indicated wear rates of ceramic knee implants that are comparable to traditional low wear material couplings (Figure 1), and are within the range of clinically established devices.

The purpose of this study was to directly compare two TKR designs, one fixed bearing and one mobile bearing, each made of traditional CoCr to one made of alumina matrix composite (BIOLOX®delta, CeramTec, Germany) ceramic material. The BPK-S Rotating Platform System (Peter-Brehm, Germany; Figure 2) and the MULTIGEN PLUS fixed bearing (Lima, Italy) were knee simulator wear tested according to ISO 14243-1 (2002). A total of three specimens plus one loaded soak control for each group (four groups in total) was subjected to 5 million standard gait cycles. The anterior-posterior (AP) and internal-external rotational (IE) motion of the implants resulting from the external load application of this force controlled test was recorded continuously. Wear was determined gravimetrically. The surface appearance of contact areas was analyzed by light microscopy and particle analysis was performed according to ISO 18129. For the mobile bearing groups, a mean wear rate of 2.47 mg per million cycles (StdDev. 0.38) was determined for the CoCr implant and of 1.10 mg per million cycles (StdDev. 0.46) for the BIOLOX®deltaimplant (Figure 3). The total AP and IE motion of the two groups did not differ. However, motion during stance phase was considerably higher for the ceramic group, indicating reduced frictional resistance (data not shown).

For the fixed bearing groups, a mean wear rate of 12.01 mg per million cycles (StdDev. 3.28) was determined for the CoCr implant and of 1.78 mg per million cycles (StdDev. 0.40) for the BIOLOX®delta implant.

Based upon the EndoLab® experience the ceramic total knee replacements tested perform as good as the best performing metallic total knee replacements. However it can be concluded that for the two implant systems tested the wear rate is reduced by more than 50% by using ceramic on polyethylene articulation when compared to an identical cobald crome design.

Introduction and Aims: A total knee replacement (TKR) needs to be well aligned for it to function well and avoid premature failure. Computer Assistance system has been designed to improve that alignment. The rationale for these systems rests on the assumptions that we currently have an alignment problem. To date, there have been no comprehensive survey of alignment outcomes and therefore no evidence of the size of the problem.

Method: The Perth CT protocol was used to measure the alignment of 164 primary TKRs, male/female = 76/88, mean age 69.4 years, performed by seven surgeons. One hundred and twenty-four patients were approached in the immediate post-operative phase and 40 within three years of surgery. Six alignment parameters were measured. The Perth Alignment Index was used as a measure of the quality of outcome. A parameter was judged perfect if it was within two degrees of the target alignment.

Results: In the coronal plane femoral alignment was ‘perfect’ in 74% (value range −3 to +6 degrees) and tibial alignment in 84% (value range −5 to +7 degrees). In the sagittal plane femoral flexion/extension was perfect in 75% (range −3 to +9 degrees), while tibial slope was perfect in 44% (value range −6 to +16 degrees). Femoral component rotation was perfect in 66% (range −8 to +9 degrees) and femorotibial matching was 45% (−14 to +13degrees). The mean PAI was 5.11:1.98, with only 14 patients (9%) having a perfect score.

Conclusion: The alignment of conventional jig-assisted TKR is far from perfect and efforts to improve the results seem to be justified.

Introduction: Total Knee Replacement (TKR) is a routine and common orthopaedic operation. Approximately 600 TKRs are performed annually at Royal Bournemouth Hospital. Although contemporary advice is that these patients should have long-term follow-up, there is very little evidence to support this protocol that involves considerable resources. We have had a policy of early discharge from follow-up (6–12 weeks) for over 10 years.

Purposes of the study: To validate the efficacy of the policy of early discharge after total knee arthroplasty at 8–10 years post surgery and to identify whether this policy has made revision surgery more difficult or complex as a result of possible late presentation.

Methods: 798 consecutive patients who underwent primary Total and Unicompartmental knee arthroplasy at Royal Bournemouth Hospital during the period 1 April 1994 to 31 March 1996 were identified. Medical records and operative notes were analysed for all patients from this cohort who have had any further surgery on their index knee. The waiting lists were also checked to identify patients from this cohort waiting for further surgery.

Results: The mean age at index operation was 72 years (range 37 to 92 years). 39/798 patients (4.9%) have had revision surgery at 8–10 years follow-up. Many of the revisions were performed on patients with early problems and 15/39(38%) of the revisions were performed on patients who were rereferred to clinic. There was a 1.1% deep infection rate leading on to revision (9 knees).

8/39 of revisions were for resurfacing the patella (20%). One patient who had a complex patella fracture needing patellectomy later had further revision surgery for instability requiring posterior stabilised components. In no patient was the revision surgery compromised or made reconstructable due to delayed presentation. In total 3 patients required bone grafting of contained cavities and only 5 knees with aseptic loosening required revision implants with stems.

Conclusion: We do not accept the need for long-term follow-up of successful implants especially whilst using prostheses with a proven track record in elderly patients.