Revision Total Knee Replacement Research Articles

Revision of failed unicompartmental knee replacement to total knee replacement

Recent reports suggest good outcome results following unicompartmental knee replacement (UKR). However, a number of authors have commented on the problem of osseous defects requiring technically difficult revision surgery. We reviewed clinical outcomes following revision total knee replacement (TKR) for failed UKR and analysed the reasons for failure and the technical aspects of the revision surgery.Between 2001 and 2010 our institute performed 132 UKR's out of which 33 required revision to TKR during a period 6years. Demographics, details and indications for primary and revision surgery, the revised prosthesis including augments, technical difficulties and complications were noted. Patient outcome assessment was based on the Oxford knee score (OKS). Survival analysis for the UKR prosthesis was calculated using Kaplan–Meier Survival curves.Reasons for revision included aseptic loosening, persistent pain, dislocated meniscus, mal-alignment and other compartment osteoarthritis. Median time to revision was 19months (range 2–159). Using revision as the end-point the survival proportion at 5-years was 69%. 18 revisions required additional intra-operative constructs including stemmed implants, wedge augmentation or bone graft. The mean 1year post-operative OKS was 29 compared to 39 for primary TKR during the same period (p<0.001).Aseptic loosening was the commonest mode of failure. UKR survivorship at a non-specialist institute is considerably lower than at originating centres. Two thirds of the revisions were technically difficult and required additional constructs. The clinical outcome after revision surgery was inferior to that of primary TKR. The role of UKR needs to be more clearly defined.

Retrospective Audit of Blood Transfusion and Comparison with Haemoglobin Concentration in Patients Undergoing Elective Primary and Revision Lower Limb Arthroplasty

We retrospectively audited the incidence of blood transfusion and related this to preoperative haemoglobin levels in 181 patients undergoing lower limb arthroplasty over a six-month period. This included 102 primary total knee replacements, 52 primary total hip replacements, 11 revision total knee replacements and 16 revision total hip replacements. The overall incidence of transfusion was 16.0%. The incidence in primary arthroplasty was 11% (9.8% for total knee replacements and 13.5% for total hip replacements), and in revision surgery was 44.4% (27.3% for total knee replacements and 56.3% for total hip replacements). Combining data for primary total knee replacements and primary total hip replacements, a preoperative haemoglobin threshold of 120 g/l divided patients into high and low risk groups for transfusion. Below or equal to this threshold the incidence of transfusion was 47.7%; above this threshold the incidence was 7.2%. We suggest that patients having primary lower limb arthroplasty with a preoperative haemoglobin of 120 g/l or less should undergo investigation of their anaemia and optimisation of erythropoeisis.

International survey of primary and revision total knee replacement

Total knee arthroplasty (TKA) is currently the international standard of care for treating degenerative and rheumatologic knee joint disease, as well as certain knee joint fractures. We sought to answer the following three research questions: (1) What is the international variance in primary and revision TKA rates around the world? (2) How do patient demographics (e.g., age, gender) vary internationally? (3) How have the rates of TKA utilization changed over time? The survey included 18 countries with a total population of 755 million, and an estimated 1,324,000 annual primary and revision total knee procedures. Ten national inpatient databases were queried for this study from Canada, the United States, Finland, France, Germany, Italy, the Netherlands, Portugal, Spain, and Switzerland. Inpatient data were also compared with published registry data for eight countries with operating arthroplasty registers (Denmark, England & Wales, Norway, Romania, Scotland, Sweden, Australia, and New Zealand). The average and median rate of primary and revision (combined) total knee replacement was 175 and 149 procedures/100,000 population, respectively, and ranged between 8.8 and 234 procedures/100,000 population. We observed that the procedure rate significantly increased over time for the countries in which historical data were available. The compound annual growth in the incidence of TKA ranged by country from 5.3% (France) to 17% (Portugal). We observed a nearly 27-fold range of TKA utilization rates between the 18 different countries included in the survey. It is apparent from the results of this study that the demand for TKA has risen substantially over the past decade in countries around the world.

Early Results of the Use of Tantalum Femoral Cones for Revision Total Knee Arthroplasty

The optimum treatment method for large femoral bone defects during revision knee replacement has not been established. The purpose of the present study was to determine the initial results associated with the use of porous tantalum metaphyseal cones for the treatment of severe femoral bone loss at the time of revision total knee arthroplasty. Porous tantalum metaphyseal cones were implanted during twenty-four revision total knee replacements. The study group included thirteen women and eleven men with a mean age of sixty-four years at the time of the procedure. The indications for the revision procedure included aseptic loosening of the femoral component (eleven patients), second-stage reimplantation for the treatment of deep infection (seven patients), severe osteolysis around a well-fixed femoral component (three patients), periprosthetic femoral fracture (two patients), and severe knee instability (one patient). The patients were followed for an average of thirty-three months (range, twenty-four to fifty months). Overall, the average Knee Society clinical score improved from 55 points preoperatively to 81 points at the time of the latest follow-up. Radiographic evaluation was completed for twenty patients after a mean duration of follow-up of thirty-five months. All femoral cones appeared well fixed radiographically, with no evidence of complications related to the cone. At the time of short-term follow-up, the porous tantalum metaphyseal femoral cones effectively provided structural support for the femoral implants of a revision total knee arthroplasty in this series. The potential for long-term biologic fixation may provide durability for reconstructions. Long-term follow-up and comparison with alternative reconstructive techniques will be required to evaluate the true effectiveness of this implant.

The risk of peri-prosthetic fracture after primary and revision total hip and knee replacement

Peri-prosthetic fracture after joint replacement in the lower limb is associated with significant morbidity. The primary aim of this study was to investigate the incidence of peri-prosthetic fracture after total hip replacement (THR) and total knee replacement (TKR) over a ten-year period using a population-based linked dataset. Between 1 April 1997 and 31 March 2008, 52,136 primary THRs, 8726 revision THRs, 44,511 primary TKRs, and 3222 revision TKRs were performed. Five years post-operatively, the rate of fracture was 0.9% after primary THR, 4.2% after revision THR, 0.6% after primary TKR and 1.7% after revision TKR. Comparison of survival analysis for all primary and revision arthroplasties showed peri-prosthetic fractures were more likely in females, patients aged > 70 and after revision arthroplasty. Female patients aged > 70 should be warned of a significantly increased risk of peri-prosthetic fracture after hip or knee replacement. The use of adjuvant medical treatment to reduce the effect of peri-prosthetic osteoporosis may be a direction of research for these patients.

The Cost Utility of Autologous Chondrocytes Implantation Using ChondroCelect® in Symptomatic Knee Cartilage Lesions in Belgium

Knee cartilage lesions increase the risk of developing osteoarthritis (OA), and may eventually result in a total knee replacement (TKR). There is currently no consensus on the optimal treatment of cartilage lesions. ChondroCelect® (CC) is a cell-based therapy approved for use in autologous chondrocytes implantation (ACI) to treat symptomatic cartilage defects of the femoral condyle. Its capacity to safely restore good-quality cartilage was demonstrated in a randomized controlled trial (RCT) versus the surgical procedure microfracture (MFX). This study investigated the cost utility of CC used in ACI compared with MFX to treat symptomatic knee cartilage lesions in Belgium. A decision tree model comparing CC with MFX over a 40-year horizon was developed in TreeAge Pro™. The key timepoints of the model were (i) clinical assessment 5 years after initial intervention (success or no success, with or without re-operation); (ii) development of OA at 15 years (yes/no); (iii) need for TKR at 20 years (yes/no); and (iv) need for prosthesis revision at 35 years (yes/no). Clinical data provided by the RCT of CC versus MFX were the clinical success (response) rate based on the Knee injury and Osteoarthritis Outcome Score (KOOS) at 36 months (82.9% vs 62.0%; p = 0.048) and the proportion of good structural repair/presence of hyaline cartilage based on International Cartilage Repair Society (ICRS II) visual item at 12 months (44.9% vs 23.2%; p = 0.023). Utility scores by surgery outcome were derived from the SF-36 questionnaire responses collected in the RCT. Conservative assumptions related to the incidences of OA, TKR and prosthesis revision relied on a literature search. A patient chart review (n = 82) provided follow-up costs by surgery outcome. National tariffs were applied to direct medical resources used (healthcare payer perspective, year 2008 costs). Annual discounting was applied to costs (3%) and effects (1.5%) as recommended by the Belgian pharmacoeconomic guidelines. The incremental cost per QALY gained for CC compared with MFX was €16,229, with a difference in costs of €20,802 and 1.282 QALYs gained. Sensitivity analyses indicated that the key model drivers were the proportion of patients with hyaline cartilage and the correlation between hyaline cartilage formation and later avoidance of OA. Probabilistic sensitivity analyses showed robustness of the results, with 80% of the simulations below the usual UK National Institute for Health and Clinical Excellence (NICE) threshold of €22,000 per QALY. Assuming a good correlation between high-quality cartilage repair and avoidance of OA at a later stage, the benefits of the cell therapy CC over MFX in terms of QALYs gained and OA-related costs avoided appear real. Further research is required to explore long-term effects of cartilage repair and reduce uncertainty on quality of life of patients with OA before and after joint replacement.

Failures of the Dual Articular knee prosthesis due to fracture of the polyethylene post

The Dual Articular (DA) total knee replacement was designed for revision and complex primary knee arthroplasty. A number of these knees failed due to fracture of the polyethylene post. We aimed to identify the proportion of DA prostheses that failed in this manner in our hospital. The hospital database was interrogated to identify all patients undergoing revision total knee replacement under the care of one surgeon from 1995 to 2007. Case notes were then reviewed to collect information about the history surrounding the knee surgery, and determine the patient's weight at the time of surgery. Telephone follow-up was carried out to obtain complete contemporary data. Forty-eight prostheses were implanted into 39 patients (21 male, 18 female). Thirty-two of the prostheses were DA and of these, 7 underwent arthroscopy or arthrotomy to reveal a fracture of the polyethylene post (22%). T-tests showed no statistical difference in age (p = 0.73) or weight (p = 0.79) between the group of DA patients with fractured posts and those without. Six of the 7 fractures were in male patients (Chi-squared; p = 0.01). Patients complained of pain, clicking and instability at a mean of 7 years post-surgery. Sixteen DA2000 prostheses were implanted, but none of these had failed due to a fractured polyethylene post. A high proportion of DA prostheses failed due to post fracture. We recommend that patients with DA prostheses be kept under review to detect failures early. Pain, clicking and instability should be investigated with arthroscopy and the tibial insert exchanged as appropriate.

Rates of infection and revision in patients with renal disease undergoing total knee replacement in Scotland

We undertook a study to determine the rates of infection and revision of total knee replacement (TKR) in patients with renal failure, renal transplantation and those undergoing renal dialysis in Scotland. The overall early and late infection rates were 1.10% and 2.19% compared with 1.06% and 2.01%, respectively, for non-renal patients. Patients with renal failure had a significantly increased risk of early infection (1.6%, relative risk 1.52, p = 0.002) and late infection (4.47%, relative risk 2.22, p < 0.001). Those on renal dialysis had significantly increased risks of late infection (8.03%, relative risk 3.99, p < 0.001) and early revision (3.70%, relative risk 4.40, p < 0.001). Renal transplant patients had a significantly increased risk of late infection, regardless of whether renal transplantation occurred before TKR (9.09%, relative risk 4.517, p = 0.027) or at any time (8.0%, relative risk 3.975, p = 0.047). There were significantly increased rates of comorbidities associated with infection for all the renal patient groups. Logistic regression analysis showed that renal failure and renal dialysis were independent risk factors for early infection and revision, respectively.

CandidaInfection in Total Knee Arthroplasty with Successful Reimplantation

Fungal infections associated with prosthetic joints are uncommon. The first case report describes a woman with insidious onset of a candidal infection of a revision total knee arthroplasty. After multiple joint debridements and prolonged antibacterial and antifungal therapy, she had a successful reimplantation of a knee prosthesis. The second case report concerns a man who had a primary cemented total knee arthroplasty that became infected with Candida albicans. He underwent resection arthroplasty with eventual replant without recurrence at 20 years. Although resection arthroplasty should be maintained as the gold standard in the surgical treatment of this problem, the first case shows a successful short-term outcome ofreimplantation of a patient with fungal infection of long-stemmed, revision total knee replacement. It also shows a treatment failure with fluconazole that was cured by voriconazole and caspofungin, two more recently developed antifungal agents.

Navigated Revision TKR: A Comparative Study with Conventional Instruments

We selected 86 cases for the study: 50 navigated revision total knee replacements (TKRs) and 36 conventional revision TKRs. We hypothesized that the rate of satisfactory implantation would be higher for navigated revision TKR than for conventional revision TKR. The primary criterion was the rate of optimally implanted prostheses on postoperative anteroposterior and lateral long leg radiographs. Thirty-one navigated cases (62%) and 14 conventional cases (39%) had an optimal global implantation (P<.05). The use of a standard navigation software for revision TKR allows a significant improvement of the accuracy of implantation. However, development of dedicated software will allow addressing more precisely the specific features of a revision TKR, such as stem extension navigation, defects filling, and joint line reconstruction.

Distal femoral varus osteotomy outcome: Is associated femoropatellar osteoarthritis consequential?

Distal femoral varus osteotomy (FVO) can be indicated for young active patients who have lateral unicompartmental osteoarthritis in a valgus knee originating in the femur. However, its indication remains controversial when associated patellofemoral osteoarthrosis is present. Associated patellofemoral osteoarthrosis influences the results of osteotomy in cases of lateral tibiofemoral osteoarthrosis. Twenty patients (22 knees) underwent opening wedge FVO for lateral tibiofemoral osteoarthrosis of a valgus knee. The osteoarthrosis was lateral and unicompartmental in 11 cases, associated with patellofemoral osteoarthrosis in nine cases, and global in two cases. The osteotomy site was fixed with a 95° blade plate in all cases. At a mean follow-up of 54months, all the patients were evaluated using the International Knee Society (IKS) score. Eighteen knees had good or excellent results (80%), two had fair results (9.5%), and two had poor results (9.5%). One female patient underwent total knee replacement revision at 8years and three others are awaiting total knee replacement. The mean preoperative IKS score increased from 49.28 (range, 14-70) to 74.23 (range, 41-92) at the last follow-up. The mean preoperative functional score increased from 50.68 (range, 30-80) to 72.85 (range, 40-90) at the last follow-up (p=0.001). The 8-year survival rate was 91% (confidence interval, 69-100%). We noted improvement in patellofemoral syndrome and recentering of the patella in seven cases out of nine with severe patellofemoral osteoarthrosis. Distal femoral varus osteotomy, with lateral opening wedge and fixation can be a good alternative to treatment of lateral tibiofemoral osteoarthritis associated with a valgus knee originating in the femur. The association of patellofemoral osteoarthritis does not affect the functional results. Level IV. Retrospective study.

Multi-ligament instability after early dislocation of a primary total knee replacement — Case report

Peripheral nerve blocks have found increased popularity in providing prolonged post-operative analgesia following total knee replacement surgery. They generally provide effective analgesia with fewer complications than epidurals. This report describes an acute low-energy knee dislocation after a well balanced, fixed bearing, cruciate-retaining primary total knee replacement performed under a spinal anaesthetic with combined complimentary femoral and sciatic nerve blocks. The dislocation was not accompanied by neurovascular compromise. Due to the subsequent instability and injury to both collaterals, the posterior cruciate ligament and posterolateral corner structures, the knee was treated with a rotating-hinge revision total knee replacement. The dislocation occurred whilst the peripheral nerve blocks (PNB) were still working. We review our incidence of PNB related complications and conclude that PNB remain a safe and effective analgesia for total knee replacements. However, we advocate that ward staff and patients should be sufficiently educated to ensure that unaided post-operative mobilisation is prevented until such a time that patients have regained complete voluntary muscle control.

Custom-made hinged spacers in revision knee surgery for patients with infection, bone loss and instability

Polymethyl methacrylate spacers are commonly used during staged revision knee arthroplasty for infection. In cases with extensive bone loss and ligament instability, such spacers may not preserve limb length, joint stability and motion. We report a retrospective case series of 19 consecutive patients using a custom-made cobalt chrome hinged spacer with antibiotic-loaded cement. The “SMILES spacer” was used at first-stage revision knee arthroplasty for chronic infection associated with a significant bone loss due to failed revision total knee replacement in 11 patients (58%), tumour endoprosthesis in four patients (21%), primary knee replacement in two patients (11%) and infected metalwork following fracture or osteotomy in a further two patients (11%). Mean follow-up was 38 months (range 24–70). In 12 (63%) patients, infection was eradicated, three patients (16%) had persistent infection and four (21%) developed further infection after initially successful second-stage surgery. Above knee amputation for persistent infection was performed in two patients. In this particularly difficult to treat population, the SMILES spacer two-stage technique has demonstrated encouraging results and presents an attractive alternative to arthrodesis or amputation.

Salmonella infection of a total knee replacement

Salmonella enterica serotype Choleraesuis is a rare infective pathogen in total knee arthroplasty and accounts for less than 1% of all cases. In the United Kingdom, the most prevalent organisms are Staphylococci, which account for over 50% of cases. We present an interesting case report of an infected revision total knee replacement following foreign travel to a region with an increased prevalence of Salmonella. The patient presented typically with an effused knee and raised inflammatory markers. Tissue samples demonstrated Salmonella choleraesuis as the infective organism. Though this serotype has previously been isolated from an infected total hip prosthesis, we believe this could be the first reported case involving a total knee replacement. Following involvement of our microbiology team and aggressive antibiotic therapy, the patient was successfully treated with two-stage revision surgery and at one-year post-op is making a satisfactory recovery.

An Overview about Biomedical Applications of Micron and Nano Size Tantalum

Tantalum is obtained from the minerals colombite, tantalite and euxenite. It is greyish silver, heavy and very hard. Tantalum does not react with body fluids and is used to make surgical equipment. Tantalum also does not irritate the body and is used to make surgical sutures as well as implants, such as artificial joints and cranial plates. Bone growth around tantalum covered by calcium phosphate is described by in vitro experimentations. in vivo. Bioactive properties of porous tantalum have been recently developed. Porous tantalum consists of an interconnected porous structure with an average porosity diameter of approximately 400 microm. Hollow spheres with nanometre-to-micrometer dimensions are widely used in different range of applications such as drug delivery carriers and bioreactors. Porous tantalum metal is currently used in orthopaedic for manufacturing of structural component for primary and revision total hip and knee replacements and, more recently, in spine surgery. Good clinical outcomes have been achieved especially in hip revision surgery, using tantalum implants, and promising short term follow up have been reported for knee revision surgery. Some patents for tantalum biomedical applications have been obtained and this article reviews various recent patents on this material. Many patents are developed on tantalum for biomedical application. This paper review some of them with particular interested for biomedical applications in orthopaedic and dentistry.

Pseudoaneurysm after revision total knee arthroplasty

Arterial vascular complications following knee replacement are uncommon with reported incidence ranging from 0.03 to 0.12%. The complication rate is rising with increased number of primary and revision total knee replacements. Vascular complications following TKR can result in arterial thrombosis, AV fistula, haemorrhage, pseudoaneurysm and arterial transection. They are associated with significant morbidity and can be limb-threatening. Early recognition and management of vascular injury is essential although some times its presentation may be delayed. We report a case of pseudoaneurysm arising from inferior lateral genicular branch of the anterior tibial artery after revision right total knee replacement.

Severe tibial bone loss in revision total knee replacement managed with structural femoral head allograft: A prospective case series from the Royal London Hospital

Large tibial bone defects may cause problems at the time of revision total knee replacement. We report on 15 patients (15 knees) followed at a mean of 5.4 years (33–115 months) who underwent revision total knee replacement for severe tibial bone loss using shaped femoral head allograft and Freeman–Samuelson revision components (Zimmer, Winterthur, Switzerland). The mean American Knee Society Score pre-operatively was 22.7 points (0–45) increasing to a mean of 77.2 points (15–95) after operation. The survivorship for the series at 6 years was seven out of nine knees. One patient required an above knee amputation at 3.5 years, whilst another underwent a second revision TKR procedure at 3.4 years. Thirteen knees did not require further surgery and showed a mean time for allograft incorporation of 1.9 years (12–36 months) with no component migration.Severe tibial bone loss at the time of revision TKR surgery is a difficult problem to treat. Our case series demonstrates that when shaped femoral heads are used as structural allograft along with long stemmed components a successful result can be achieved.

Use of Porous Tantalum Metaphyseal Cones for Severe Tibial Bone Loss During Revision Total Knee Replacement

The best treatment method for large tibial bone defects during revision knee replacement has not been established. The purpose of this study was to determine the initial results obtained with a unique reconstructive implant, the porous tantalum metaphyseal cone, designed as an alternative treatment for severe tibial bone loss following total knee arthroplasty. Porous tantalum metaphyseal cones were implanted during fifteen revision total knee replacements in eight women and seven men who had an average age of 68.1 years at the time of the procedure. The patients had had an average of 3.5 prior total knee replacements. According to the Anderson Orthopaedic Research Institute bone defect classification, eight knees had a Type-3 defect and seven knees had a Type-2B bone defect. All patients were followed clinically and radiographically. The patients were followed for an average of thirty-four months (range, twenty-four to forty-seven months). Overall, the average Knee Society clinical scores improved from 52 points preoperatively to 85 points at the time of the final follow-up. At the final follow-up evaluation, all fifteen porous metaphyseal cones showed evidence of osseointegration with reactive osseous trabeculation at points of contact with the tibia. There was no evidence of loosening or migration of any of these tibial reconstructions at the time of final follow-up. At the time of short-term follow-up, the porous tantalum metaphyseal tibial cones effectively provided structural support for the tibial implants in this series. The potential for long-term biologic fixation may provide durability for these tibial reconstructions. Long-term follow-up and comparison with alternative reconstructive techniques will be required to evaluate the true effectiveness of this treatment approach.

Repair of defects and containment in revision total knee replacement

The treatment of bony defects of the tibia at the time of revision total knee replacement is controversial. The place of compacted morsellised bone graft is becoming established, particularly in contained defects. It has previously been shown that the initial stability of impaction-grafted trays in the contained defects is equivalent to that of an uncemented primary knee replacement. However, there is little biomechanical evidence on which to base a decision in the treatment of uncontained defects. We undertook a laboratory-based biomechanical study comparing three methods of graft containment in segmental medial tibial defects and compared them with the use of a modular metal augment to bypass the defect. Using resin models of the proximal tibia with medial defects representing either 46% or 65% of the medial cortical rim, repair of the defect was accomplished using mesh, cement or a novel bag technique, after which impaction bone grafting was used to fill the contained defects and a tibial component was cemented in place. As a control, a cemented tibial component with modular metal augments was used in identical defects. All specimens were submitted to cyclical mechanical loading, during which cyclical and permanent tray displacement were determined. The results showed satisfactory stability with all the techniques except the bone bag method. Using metal augments gave the highest initial stability, but obviously lacked any potential for bone restoration.

Lactobacillus as a rare cause of an infected total knee replacement: a case report

IntroductionWe report a rare case of an infected revision total knee replacement as a result of a Lactobacillus species infection. Lactobacillus infections have been associated with prolonged broad-spectrum antibiotic use. This can have implications in revision surgery, especially when patients have been on previous long-term suppressive antibiotic therapy.Case presentationAn 81-year-old British man with a previous history of complex revision knee arthroplasty for infection presented with a hot, swollen knee joint. He had previously been on long-term suppressive antibiotic therapy. Aspiration of the knee joint yielded a culture of Lactobacillus species.ConclusionIn patients undergoing revision joint arthroplasty, especially for previous infection, the presence of common and uncommon bacterial species must be excluded and eradicated before further surgical intervention.