Knee arthrodesis--a review

Early results of a novel modular knee arthrodesis implant after uncontrolled periprosthetic knee joint infection

AIM

The aim of this study is to evaluate the functional outcomes and complications after non-fusion knee arthrodesis with a modular segmental intramedullary implant used for infected total knee arthroplasty revisions.

METHODS

A retrospective review of the patients who had been surgically treated with a modular intramedullary arthrodesis implant for recurrent infection after revision TKA between January 2016 and February 2020 were included. The indications for arthrodesis were failed infected TKA with massive bone loss, deficient extensor mechanism and poor soft tissue coverage that precluded joint reconstruction with revision TKA implants. Clinical outcomes were assesed with visual analogue scale for pain (pVAS), Oxford knee score (OKS) and 12-item short form survey (SF-12). Full-length radiographs were used to verify limb length discrepancies (LLD).

RESULTS

Fourteen patients (4 male and 10 female) patients with a mean age of 69.3 (range, 59 to 81) years at time of surgery were available for final follow-up at a mean of 28.8 months (range, 24-35 months). All clinical outcome scores improved at the final follow-up (pVAS, 8.5 to 2.6, p = .01; OKS, 12.6 to 33.8, p = .02; SF-12 physical, 22.9 to 32.1, p = .01 and SF-12 mental, 27.7 to 40.2, p = .01). The mean LLD was 1.0 cm (range, + 15 - 2.3 cm). Re-infection was detected in three patients (21.4%). Two patients were managed with suppressive antibiotic treatment and a third patient required repeat 2-stage revision procedure. In one patient, a periprosthetic femur fracture was observed and treated with plate osteosynthesis.

CONCLUSION

Uncontrolled infection after total knee arthroplasty can be effectively treated with arthrodesis using a modular intramedullary nail and satisfactory functional results can be obtained.

LEVEL OF EVIDENCE

Level 4, Retrospective cohort study.

A comparison of outcomes for above-knee-amputation and arthrodesis for the chronically infected total knee arthroplasty: a systematic review

INTRODUCTION

Several strategies have been shown to have some efficacy in the chronically infected total knee arthroplasty (TKA): chronic antibiotic suppression, a second two-stage revision, arthrodesis, and above-the-knee amputation (AKA). We conducted a systematic review to determine the efficacy of these treatments in patients who had previously received a two-stage revision.

METHODS

A systematic review of the literature was performed which investigated PubMed, Embase, Scopus, and Web of Science Databases. Chronic infection was defined as a persistent infection of a TKA after a previous two-stage revision. Studies were independently evaluated by two reviewers. Quality appraisal was performed using MINORS Criteria.

RESULTS

14 studies were included for the final review. For chronically infected TKA, a second two-stage revision was often sufficient to control infection. If revision failed, the most common next procedure was either a repeat revision or AKA. AKA patients had less pain and higher quality of life scores compared to arthrodesis, but a higher five-year mortality rate.

DISCUSSION AND CONCLUSION

Chronic infection in TKA offers a multitude of challenges for orthopedic surgeons. We found that arthrodesis and AKA were not significantly different in rates of infection eradication or quality of life. We recommend clinicians to actively discuss options with patients to find a procedure most suitable for them.

Selecting a high-dose antibiotic-laden cement knee spacer

Prosthetic joint infection [PJI] after total knee arthroplasty (TKA) remains a common and challenging problem for joint replacement surgeons and patients. Once the diagnosis of PJI has been made, patient goals and characteristics as well as the infection timeline dictate treatment. Most commonly, this involves a two-stage procedure with the removal of all implants, debridement, and placement of a static or dynamic antibiotic spacer. Static spacers are commonly indicated for older, less healthy patients that would benefit from soft tissue rest after initial debridement. Mobile spacers are typically used in younger, healthier patients to improve quality of life and reduce soft-tissue contractures during antibiotic spacer treatment. Spacers are highly customizable with regard to antibiotic choice, cement variety, and spacer design, each with reported advantages, drawbacks, and indications that will be covered in this article. While no spacer is superior to any other, the modern arthroplasty surgeon must be familiar with the available modalities to optimize treatment for each patient. Here we propose a treatment algorithm to assist surgeons in deciding on treatment for PJI after TKA.

Knee Arthrodesis with a Modular Silver-Coated Endoprosthesis for Infected Total Knee Arthroplasty with Extensive Bone Loss: A Retrospective Case-Series Study

INTRODUCTION

Knee arthrodesis is a limb salvage intervention for persistent periprosthetic joint infection (PJI) when revision total knee arthroplasty fails. Conventional arthrodesis techniques are associated with the increased rate of complications, especially in patients with extensive bone loss and extensor tendon deficiency.

METHODS

Eight patients with a modular silver-coated arthrodesis implant after failed exchange arthroplasty for infection, were retrospectively reviewed. All patients had significant bone loss, while 5 displayed extensor tendon deficiency. Survivorship, complications, leg length discrepancy, median Visual Analogue Scale (VAS) and Oxford Knee score (OKS) were evaluated.

RESULTS

The median follow up was 32 months (range 24-59 months). The survivorship rate of the prosthesis was 86% during the minimum time of follow up of 24 months. In one patient recurrence of the infection was observed and above-knee amputation was performed. The median postoperative leg length discrepancy was 2.07 ± 0.67 cm. Patients were able to ambulate with mild or no pain. The median VAS and OKS was 2.14 ± 0.9 and 34.7 ± 9.3, respectively.

CONCLUSIONS

The results of our study demonstrated that knee arthrodesis with a silver coated arthrodesis implant, performed for persistent PJI in patients with significant bone loss and extensor tendon deficit, provided a stable construct, allowed eradication of infection and was associated with good functional outcome.

Challenges and opportunities in vascularized composite allotransplantation of joints: a systematic literature review

Background

Joint allotransplantation (JA) within the field of vascularized composite allotransplantation (VCA) holds great potential for functional and non-prosthetic reconstruction of severely damaged joints. However, clinical use of JA remains limited due to the immune rejection associated with all forms of allotransplantation. In this study, we aim to provide a comprehensive overview of the current state of JA through a systematic review of clinical, animal, and immunological studies on this topic.

Methods

We conducted a systematic literature review in accordance with the PRISMA guidelines to identify relevant articles in PubMed, Cochrane Library, and Web of Science databases. The results were analyzed, and potential future prospects were discussed in detail.

Results

Our review included 14 articles describing relevant developments in JA. Currently, most JA-related research is being performed in small animal models, demonstrating graft survival and functional restoration with short-term immunosuppression. In human patients, only six knee allotransplantations have been performed to date, with all grafts ultimately failing and a maximum graft survival of 56 months.

Conclusion

Research on joint allotransplantation has been limited over the last 20 years due to the rarity of clinical applications, the complex nature of surgical procedures, and uncertain outcomes stemming from immune rejection. However, the key to overcoming these challenges lies in extending graft survival and minimizing immunosuppressive side effects. With the emergence of new immunosuppressive strategies, the feasibility and clinical potential of vascularized joint allotransplantation warrants further investigation.

Knee Arthrodesis: An Analysis of Surgical Risk Factors and Complications Using a National Database

Background

Knee arthrodesis is predominantly a salvage procedure. In present time, knee arthrodesis is mostly considered for cases of unreconstructable failed total knee arthroplasty after prosthetic joint infection or trauma. Knee arthrodesis has shown better functional outcomes than amputation for these patients but has a high complication rate. The purpose of this study was to characterize the acute surgical risk profile of patients undergoing a knee arthrodesis for any indication.

Methods

The American College of Surgeons National Surgical Quality Improvement Program database was queried to determine 30-day outcomes after knee arthrodesis between 2005 and 2020. Demographics, clinical risk factors, and postoperative events were analyzed, along with reoperation and readmission rates.

Results

A total of 203 patients that underwent a knee arthrodesis were identified. Forty-eight percent of patients had at least 1 complication. The most common complication was acute surgical blood loss anemia requiring a blood transfusion (38.4%), followed by organ space surgical site infection (4.9%), superficial surgical site infection (2.5%), and deep vein thrombosis (2.5%). Smoking was associated with higher rates of reoperation and readmission (odds ratio 9, P < .01, and odds ratio 6, P < .05).

Conclusions

Overall, knee arthrodesis is a salvage procedure that has a high rate of early postoperative complications and is most often performed in patients at higher risk. Early reoperation is strongly associated with a poor preoperative functional status. Smoking places patients at higher risk of early complications.

Outcomes of Second-stage Reimplantation After Modular Knee Arthrodesis for Periprosthetic Joint Infection

Modular knee arthrodesis (MKU) is a salvage treatment for recurrent periprosthetic joint infection (PJI) or PJI associated with notable bone loss. Reimplantation endoprosthetic reconstruction (REI) is an option in patients with MKU who have PJI clearance but are not satisfied with pain or functional outcomes with MKU. The purpose of this study was to evaluate the outcomes of MKU to REI conversion.

Methodological Challenges in Predicting Periprosthetic Joint Infection Treatment Outcomes: A Narrative Review

The management of periprosthetic joint infection (PJI) generally requires both surgical intervention and targeted antimicrobial therapy. Decisions regarding surgical management–whether it be irrigation and debridement, one-stage revision, or two-stage revision–must take into consideration an array of factors. These include the timing and duration of symptoms, clinical characteristics of the patient, and antimicrobial susceptibilities of the microorganism(s) involved. Moreover, decisions relating to surgical management must consider clinical factors associated with the health of the patient, alongside the patient's preferences. These decisions are further complicated by concerns beyond mere eradication of the infection, such as the level of improvement in quality of life related to management strategies. To better understand the probability of successful surgical treatment of a PJI, several predictive tools have been developed over the past decade. This narrative review provides an overview of available clinical prediction models that aim to guide treatment decisions for patients with periprosthetic joint infection, and highlights key challenges to reliably implementing these tools in clinical practice.

Knee Arthrodesis Affects Gait Kinematics More in the Ankle Than in the Hip Joint

Background and Objectives: No gold standard exists for treating persistent periprosthetic knee infections. Knee arthrodesis represents one treatment concept for extensive bone defects and extensor system insufficiencies. It has already been shown that knee arthrodesis leads to a significant reduction in one's quality of life. The aim of this survey was to assess the influence of knee arthrodesis on the neighboring joints on the basis of gait analysis data. Our hypothesis is that the hip and ankle joints are negatively influenced by knee arthrodesis in the process of walking. Materials and methods: We performed six pedobarographic and four gait analytical measurements in six patients 2.4 ± 1.6 years after receiving knee arthrodesis at the operating ages of 69.1 ± 9.2 years. Gait analysis consisted of time-distance parameters/minute (number of steps, double support, cycle time, standing phase, step length, gait speed). A healthy group of test subjects (n = 52) was included as the control cohort. Gait analysis was conducted using a three-dimensional movement system and three force-measuring platforms to determine the ground reaction force. Foot pressure was measured using a pedography platform. Results: Five of six patients presented an incomplete rolling movement over the toes on the side that was operated on, presenting with a gait line ending in the forefoot area. All of the patients bore less weight on the side that was operated on. Three of six patients demonstrated a pathological gait line with a healthy opposite side ending in the forefoot area. All of the patients exhibited a reduction in gait speed and step length and a lower number of steps. All of the patients had a prolonged double support/cycle time. Conclusions: Isolated knee arthrodesis is associated with reduced forefoot repulsion, restricted movement on the side receiving the operation, and reduced movement in the ankle/knee joint. The hip showed norm deviations in the hip moment/angle. Knee arthrodesis causes reduced gait kinetics/kinematics. Our survey shows that the relative joint moments of the ankle joint and hip are often reduced. The ankle joint is more affected compared to the hip.

Functional Outcome of Patients Undergoing Knee Arthrodesis after Infected Total Arthroplasty

Objective  Retrospectively assess the functional outcome of patients undergoing arthrodesis after septic failure of total knee arthroplasty. Methods  Eighteen patients were evaluated, with a mean time of 3.7 years of follow-up. Arthrodesis surgery was performed using a narrow anterior dynamic compression plate, and medial or external fixator in two planes of the joint (Orthofix Bone Growth Therapy, Lewisville, TS, USA), at the surgeon's discretion. Results  The most frequent pathogen found was Staphylococcus aureus methicillin sensitive (38.9%). The mean lower limb discrepancy was 3.63 cm. The mean knee society score was 68 points. According to the visual analog scale for pain, 44% of the patients had a 0 score at the time of assessment, and 22.2% were very dissatisfied, despite the bone healing achieved. Patients were assessed for the ability to walk with or without assistance. Conclusion  Knee arthrodesis surgery was effective in controlling the infectious process and decreasing pain complaints, but satisfaction with the procedure was low.

Application of the Ilizarov technique for knee joint arthrodesis as a treatment for end-stage tuberculosis of the knee

Background

With the global determination to eliminate tuberculosis (TB), the treatment for end-stage TB of the knee joint is still a great clinical challenge. This study aims to retrospectively determine the clinical and radiographic outcomes after use of the Ilizarov technique for knee joint arthrodesis as a treatment for end-stage knee TB.

Methods

Twenty-six patients with end-stage knee TB treated by external fixation with the Ilizarov fixator between 2012 and 2017 were examined. Anti-TB drugs were administered preoperatively, intraoperatively, and postoperatively. Clinical and radiologic examinations were performed for comprehensive evaluations, and these include C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), flexion and valgus angle of the knee, leg-length discrepancy, and Lysholm score.

Results

Twenty-four patients were followed up for an average of 5.8 years (2.2–7 years). All patients achieved bone fusion within a mean of 6.4 months (4–16 months). The ESR and CRP concentrations were observed to return to normal within 5.1 ± 1.1 months postoperatively. There was no recurrence of TB. At last follow-up, the mean leg-length discrepancy was 2.7 ± 1.4 cm, and the mean alignment was 8.7 ± 2.6° flexion and 5.3 ± 1.0° valgus. No patient had a significant rotational deformity. The average Lysholm score was seen to improve significantly from 36.8 ± 18.4 preoperatively to 79.5 ± 5.9 at final follow-up (p < 0.0001).

Conclusion

This study has demonstrated that the Ilizarov technique for knee joint arthrodesis as a treatment of end-stage knee TB achieved promising outcomes with minimal complications.

Knee arthrodesis for a congenital luxation with Larsen syndrome

A 31-year-old woman with known Larsen syndrome presented with congenital chronic luxation of her right knee with increasing instability symptoms, which limited her daily activities. We refrained from a constrained knee arthroplasty due to her relatively young age and decided to perform a knee arthrodesis. Knee arthrodesis is a viable lifelong-lasting operative treatment alternative for specific instability-related knee disease. The knee arthrodesis was performed by double plating with an additional fixation of the patella. At 1-yearfollow-up, she was able to walk without limitations and did not experience any pain with complete consolidation of the arthrodesis. At 2-year follow-up, she performed all her daily activities without limitations. Both the Knee injury and Osteoarthritis Outcome Score (KOOS) and the International Knee Documentation Committee subjective knee form (IKDC) improved at 2-year follow-up (KOOS: 61.3; IKDC: 56.3) compared with 1-year follow-up (KOOS: 52; IKDC: 40.2).

Peri-implant fracture after dual-plating knee arthrodesis for failed total knee arthroplasty: case series

Knee arthrodesis is an option in the setting of failed total knee arthroplasty. Dual-plate fixation is a described technique to obtain knee fusion in this scenario. Literature on the complications of knee arthrodesis with dual-plate constructs is limited. We present 3 cases who underwent dual-plate knee arthrodesis complicated by peri-implant femur fracture.

Comparison of two-stage revision arthroplasty and intramedullary arthrodesis in patients with failed infected knee arthroplasty

BACKGROUND

Failed total knee arthroplasty (TKA) with significant bone loss and compromised soft-tissues is challenging and the final results are often inferior to patient's expectation. The objective of this study was to present a comparison of outcomes in patients with failed infected TKA treated with two-stage revision TKA or knee arthrodesis and to assess clinical and functional results, implant survival and infection recurrence. The hypothesis was that an arthrodesis may result in beneficial effects on patients' outcome.

METHODS

Clinical data of 81 patients with periprosthetic joint infection (PJI) of the knee joint were collected and analyzed retrospectively. Between 2008 and 2014, a total of 36 patients had been treated within a two-stage exchange procedure and reimplantation of a modular intramedullary arthodesis nail and 45 patients with revision TKA. Patients were treated according to the same structured treatment algorithm. Clinical and functional evaluation was performed using the Oxford knee score (OKS) and the visual analogue scale (VAS).

RESULTS

The mean follow-up was 32.9 ± 14.0 months. The rate of definitely free of infection at last follow-up in the arthrodesis group was 32 of 36 (88.9%) and 36 of 45 (80.0%) in the revision TKA group (p = 0.272). Mean VAS for pain in the arthrodesis group was 3.1 ± 1.4 compared to 3.2 ± 1.6 in the revision TKA group (p = 0.636). The OKS in the arthrodesis group was 38.7 ± 8.9 and 36.5 ± 8.9 (p = 0.246) in patients with revision TKA. Rate of revisions in the revision-TKA group was 2.8 ± 3.7 compared to 1.2 ± 2.4 in the arthrodesis group (p = 0.021).

CONCLUSION

Treatment of PJI needs a distinct therapy with possible fallback strategies in case of failure. A knee arthrodesis is a limb salvage procedure that showed no significant benefits on the considered outcome factors compared to revision TKA but is associated with significantly lower revision rate. After exhausted treatment modalities, a knee arthrodesis should be considered as an option in selected patients.

LEVEL OF EVIDENCE

Level III, retrospective cohort study.

Single stage reconstruction of post traumatic and post excisional composite perigenual defects using chimeric pedicled propelled osteomyocutaneous fibula flap

INTRODUCTION

Composite perigenual defects (CPGDs) are exacting the expertise of the reconstructive surgeons. Segmental skeletal defects continue to be a challenge for both orthopedic and plastic surgeons. There are many techniques available for the reconstruction of segmental skeletal defects in the perigenual region. This study explores the outcomes of pedicled chimeric propelled osteomyocutaneous fibula flap reconstruction of post traumatic and post excisional composite perigenual defects (CPGDs) MATERIALS AND METHODS: It was a retrospective study conducted from 2011 to 2016 including 16 patients (5 post excisional defects and 11 post traumatic defects). 14 males and 2 females were included. Ages of the patients were ranging from 24 to 46 years. All had their CPGDs reconstructed with chimeric pedicled propelled fibula osteomyocutaneous flap RESULTS: All 15 patients on an average of 26 months follow-up assumed pain free unrestrictive walking. Fracture of hardware and transferred fibula occurred in one case 2 ^1/2 years following the surgery. Other patients had good functional recovery in an average of 26 months follow up. The average MSTS score of 15 patients was 23.9.

CONCLUSION

This anatomically construed procedure will be addendum to the armamentarium of reconstruction in both post excisional limb salvage milieu and secondary posttraumatic context for the perigenual composite defects. With high healing potential, infection culling capacity, high osteogenic potential and good supportive hardwares the pedicled osteomyocutaneous fibula flap may usher in better outcome in composite perigenual defects reconstruction.

External Fixation vs Intramedullary Nailing for Knee Arthrodesis After Failed Infected Total Knee Arthroplasty: A Systematic Review and Meta-Analysis

BACKGROUND

The aim of this study is to compare intramedullary nailing with external fixation for knee arthrodesis after failed infected total knee arthroplasty (TKA). Primary outcome is radiographic union. Secondary outcomes include recurrent deep infection, revision arthrodesis, and amputation.

METHODS

Systematic review and meta-analysis of studies comparing outcomes from intramedullary nailing and external fixation in patients with infected TKA undergoing arthrodesis procedures was performed. Randomized controlled trials and cohort studies were included.

RESULTS

Intramedullary nailing achieves a significantly higher rate of radiographic union compared with external fixation (odds ratio [OR] 5.17, 95% confidence interval [CI] 2.74-9.75, P < .00001) at a mean follow-up of 44.22 months. There is no significant difference in the rate of recurrent deep infection (OR 0.91, 95% CI 0.38-2.15, P = .83) or amputation (OR 0.94, 95% CI 0.23-3.84, P = .93). The rate of revision arthrodesis procedures is significantly lower for intramedullary nailing compared with external fixation (OR 0.28, 95% CI 0.08-0.93, P = .04).

CONCLUSION

Intramedullary nailing is more effective than external fixation with respect to several clinically important outcomes. Therefore, we recommend intramedullary nailing for achieving knee arthrodesis as a salvage procedure for infected TKA in the absence of specific indications for external fixation.

Knee arthrodesis versus above-the-knee amputation after septic failure of revision total knee arthroplasty: comparison of functional outcome and complication rates

BACKGROUND

After septic failure of total knee arthroplasty (TKA) and multiple revision operations resulting in impaired function, bone and/or soft-tissue damage a reconstruction with a revision arthroplasty might be impossible. Salvage procedures to regain mobility and quality of life are an above-the-knee amputation or knee arthrodesis. The decision process for the patient and surgeon is difficult and data comparing arthrodesis versus amputation in terms of function and quality of life are scarce. The purpose of this study was to analyse and compare the specific complications, functional outcome and quality of life of above-the-knee amputation (AKA) and modular knee-arthrodesis (MKA) after septic failure of total knee arthroplasty.

METHODS

Eighty-one patients treated with MKA and 32 patients treated with AKA after septic failure of TKA between 2003 and 2012 were included in this cohort study. Demographic data, comorbidities, pathogens and complications such as re-infection, implant-failure or revision surgeries were recorded in 55MKA and 20AKA patients. Functional outcome with use of the Lower-Extremity-Functional-Score (LEFS) and the patients reported general health status (SF-12-questionnaire) was recorded after a mean interval of 55 months.

RESULTS

A major complication occurred in more than one-third of the cases after MKA and AKA, whereas recurrence of infection was with 22% after MKA and 35% after AKA the most common complication. Patients with AKA and MKA showed a comparable functional outcome with a mean LEFS score of 37 and 28 respectively (p = 0.181). Correspondingly, a comparable physical quality of life with a mean physical SF-12 of 36 for AKA patients and a mean score of 30 for MKA patients was observed (p = 0.080). Notably, ten AKA patients that could be fitted with a microprocessor-controlled-knee-joint demonstrated with a mean LEFS of 56 a significantly better functional outcome than other amputee patients (p < 0.01) or MKA patients (p < 0.01).

CONCLUSION

Naturally, the decision process for the treatment of desolate situations of septic failures following revision knee arthroplasty is depending on various factors. Nevertheless, the amputation should be considered as an option in patients with a good physical and mental condition.

Two-stage knee arthrodesis with a modular intramedullary nail due to septic failure of revision total knee arthroplasty with extensor mechanism deficiency

BACKGROUND

Periprosthetic joint infection is a serious complication and reconstruction after failed revision total knee arthroplasty with significant bone loss and compromised soft-tissues can be challenging. Objective of this study was to assess clinical and functional results, implant survival and infection recurrence rates in patients treated with two-stage arthrodesis after failed revision TKA with extensor mechanism deficiencies due to PJI, and to identify the factors that affect outcomes after surgery.

METHODS

Thirty seven patients with PJI treated within a two-stage exchange and reimplantation of an arthrodesis nail between 2008 and 2014 were included. Systemic and local risk factors were graded preoperatively according to McPherson et al. All patients were treated according to a structured treatment algorithm. Clinical and functional evaluation was performed using the Oxford Knee Score and the Visual Analogue Scale.

RESULTS

Thirty two of 37 patients (86.5%) were graded as free of infection. Five patients (13.5%) had recurrent infection after arthrodesis with the need of revision surgery. Mean leg-length discrepancy was 2.2cm. The mean VAS for pain was three, the mean Oxford Knee Score was 38±9. Total implant survival at a 74month follow-up was 74.3% (95% CI: 45.4 to 91.1%), as determined by Kaplan-Meier survival curves. Local McPherson Score, as well as number of revisions was found to be of significant influence to the survival rate.

CONCLUSIONS

Septic failure of revision knee arthroplasty can be effectively treated with two-stage arthrodesis using a modular intramedullary nail, providing a stable and painless limb with satisfactory functional results and acceptable infection eradication rates.

Knee arthrodesis: procedures and perspectives in the US from 1993 to 2011

BACKGROUND

The incidence and prevalence of knee arthrodesis (fusion) in the United States is largely unknown, in spite of numerous case reports and review articles that have called attention to this life altering procedure.

PURPOSE

This study was conducted to determine long-term knee arthrodesis incidence and patient populations, and to characterize the associated healthcare burden.

METHODS

The Nationwide Inpatient Sample was used to evaluate knee arthrodesis procedures performed in the United States between 1993 and 2011. Patient age, sex, and reimbursement method were evaluated along with hospital attributes. Procedural rates for individual demographics were calculated using population data from the US Census. Commonly occurring diagnoses and procedures in knee arthrodesis were compiled.

RESULTS

The annual number of reported knee arthrodesis procedures remained relatively unchanged between 1993 and 2011 (Mean 1014, Standard Deviation 113), but there was a small but significant decrease in the procedure rate when taking population changes into account. Over 80 % of patients were aged 45 or above. Approximately 65 % of patients utilized governmental payers for reimbursement. Nearly all of the procedures were performed in metropolitan area hospitals (92.5 %), and a significant majority performed in teaching hospitals (62 %).

CONCLUSIONS

The low incidence of knee arthrodesis procedures reflects both clinician and patient antipathy for this undesirable surgery. Case studies continue to reflect an interest to improve methodology, but also suggest a significant number of patients that go untreated given the current state of the art. Future work should seek to quantify the prevalence of patients with a severely dysfunctional knee who might otherwise undergo arthrodesis, but opt against it given the significant quality of life issues associated with the procedure.

Knee Arthrodesis After Failure of Knee Arthroplasty: A Nationwide Register-Based Study

BACKGROUND

Arthrodesis is considered a salvage procedure after failure of a knee arthroplasty. Data on the use of this procedure are limited. The purpose of this study was to identify the incidence, causes, surgical techniques, and outcomes of arthrodesis after failed knee arthroplasty in a nationwide population.

METHODS

Data were extracted from the Danish Civil Registration System, the Danish National Patient Register, and the Danish Knee Arthroplasty Register. A total of 92,785 primary knee arthroplasties performed in Denmark from 1997 to 2013 were identified by linking the data using the unique personal identification number assigned to each patient. Of these arthroplasties, 165 were followed by arthrodesis. Hospital records of all identified cases of arthrodesis were reviewed. A competing risk model was used to estimate the cumulative incidence of arthrodesis in the study period. Differences in cumulative incidence were compared with the Gray test.

RESULTS

A total of 164 of the 165 arthrodeses were performed for causes related to failed knee arthroplasty. The 15-year cumulative incidence of arthrodesis was 0.26% (95% confidence interval, 0.21% to 0.31%). The 5-year cumulative incidence decreased significantly (p < 0.0001) from 0.32% for arthroplasties performed from 1997 to 2002 to 0.09% for arthroplasties performed from 2008 to 2013. The most common causes of arthrodesis were periprosthetic infection in 152 patients (93%), extensor mechanism disruption in 46 (28%), soft-tissue deficiency in 25 (15%), and severe bone loss in 11 (7%). In 79 patients (48%), there were 2 or more indications for arthrodesis. Solid fusion was achieved in 65% of the patients. The fusion rate was significantly higher after intramedullary nail fixation compared with external fixation (p = 0.01). A total of 34 patients (21%) underwent repeat arthrodesis, and 23 patients (14%) eventually underwent transfemoral amputation.

CONCLUSIONS

The cumulative incidence of arthrodesis within 15 years after primary knee arthroplasty was 0.26%. There was a significant decrease in the 5-year cumulative incidence during the study period, suggesting an overall improvement in prevention of this adverse outcome of knee arthroplasty.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Conversion of a Surgically Arthrodesed Knee to a Total Knee Arthroplasty-Is it Worth it? A Meta-Analysis

BACKGROUND

Conversion of a surgically arthrodesed knee to total knee arthroplasty (TKA) is an option for a select group of patients who are not satisfied with their results. However, there is a paucity of literature on this topic. A systematic review of literature was performed to (1) describe the overall demographic characteristics; (2) evaluate the clinical outcomes; (3) determine the overall rate of complications; and (4) evaluate the overall satisfaction of patients who underwent conversion of an arthrodesed knee to TKA.

METHODS

A comprehensive literature search was systematically performed to evaluate all studies included in the literature until July 2015. The specific search terms used were "fusion knee" and "arthrodesis knee," which revealed a total of 2206 studies. A review and selection of these abstracts were then performed based on inclusion and/or exclusion criteria; a total of 10 articles were used for final review.

RESULTS

There were a total of 98 surgically arthrodesed knees that subsequently underwent TKA. Patients had a mean age of 55 years and were followed up for a mean of 5 years. Using a random effects model, there was an overall complication rate of 47%, an overall revision rate of 25%, and an overall failure rate of 11%. However, most patients were overall satisfied with the procedure.

CONCLUSION

Fusion takedown is a challenging procedure that should only be performed by experienced surgeons after extensive discussion with the patients. The clinical outcomes are good with overall patient satisfaction, but complication rates are high including risk of repeat fusion or amputation.

Knee arthrodesis with a long intramedullary nail as limb salvage for complex periprosthetic infections

BACKGROUND

Periprosthetic infection following total knee arthroplasty is a devastating complication, which is not always satisfactorily resolved by revision surgery. Arthrodesis is a salvage alternative to above-knee amputation or permanent resection arthroplasty. Fixation options include internal compression plating, external fixation, and intramedullary nails.

METHODS

We retrospectively reviewed twelve consecutive cases (9 males, 3 females; mean age, 67 years) of knee arthrodesis with a long intramedullary nail, performed at a single institution between 2003 and 2014. Desired outcomes were the ability to mobilize without pain, solid radiographic fusion, and the eradication of infection.

RESULTS

Mean follow-up was 48.5 months (range, 9-120 months). Eleven patients (92 %) demonstrated stable fusion, ten patients (83 %) were ambulatory without pain, and ten patients (83 %) remained without infection at most recent follow-up. Eight patients (67 %) achieved union at an average of 12 months; three required repeat procedures, achieving union at an average of 9 months. There was a significant difference (P < 0.01) between the numbers of previous operations amongst the eight patients who initially achieved union (mean, 3.25) and three who subsequently required repeat procedures (mean, 8.33).

CONCLUSIONS

In contrast to similar studies, we performed a single-stage exchange where possible, while comparable ambulatory and fusion rates were observed. Numerous previous attempts at revision arthroplasty, co-morbidities, and infections with highly resistant organisms have been associated with further complications. Although technically challenging, knee arthrodesis with a long intramedullary nail offers an acceptable limb salvage procedure for carefully selected patients with complex periprosthetic infections.

The SIGN nail for knee fusion: technique and clinical results

Purpose: Evaluate the efficacy of using the SIGN nail for instrumented knee fusion.

Methods: Six consecutive patients (seven knees, three males) with an average age of 30.5 years (range, 18–50 years) underwent a knee arthrodesis with SIGN nail (mean follow-up 10.7 months; range, 8–14 months). Diagnoses included tuberculosis (two knees), congenital knee dislocation in two knees (one patient), bacterial septic arthritis (one knee), malunited spontaneous fusion (one knee), and severe gout with 90° flexion contracture (one knee). The nail was inserted through an anteromedial entry point on the femur and full weightbearing was permitted immediately.

Results: All knees had clinical and radiographic evidence of fusion at final follow-up and none required further surgery. Four of six patients ambulated without assistive device, and all patients reported improved overall physical function. There were no post-operative complications.

Conclusion: The technique described utilizing the SIGN nail is both safe and effective for knee arthrodesis and useful for austere environments with limited fluoroscopy and implant options.

No improvement in the post-TKA infection prognosis when the implant is not reimplanted: Retrospective multicentre study of 72 cases

INTRODUCTION

For the surgeon and patient, permanent removal of an infected knee prosthesis is an unwelcome decision taken out of necessity because unfavourable local or general conditions may increase the likelihood of mechanical or infectious failure upon prosthesis reimplantation. The purpose of this study was to determine if permanent removal of an infected total knee arthroplasty (TKA) implant controls the infection and prevents above-the-knee amputation when reimplantation turns out to be too risky. It was hypothesized that removal without reimplantation contributes to eradicating the infection and helps to avoid amputation.

PATIENTS AND METHODS

Seventy-two consecutive patients who underwent TKA removal between 2000 and 2010 at 14 hospitals were reviewed. The TKA removal was followed by knee fusion in 29 cases or implantation of a permanent cement spacer in 43 cases.

RESULTS

If failure is defined as clinically obvious recurrence of the infection, the survival rate was 65 ± 5% at 2 years; 44% of patients had a recurrence of the infection, 8% had undergone amputation and 19% presented with nonunion at the last follow-up. The male gender and the presence of multiple co-morbidities were predisposing factors for failure.

DISCUSSION

Control of the infection is not guaranteed upon TKA implant removal; the success rate is lower than in cases of two-stage reimplantation. The outcomes in this study are worse than those of other published studies. This is likely due to the heterogeneity in the patient population and treatments, along with the presence of co-morbidities. This treatment option should be the last recourse before amputation.

Knee arthrodesis using a unilateral external fixator combined with crossed cannulated screws for the treatment of end-stage tuberculosis of the knee

Background

The treatment of end-stage tuberculosis (TB) of the knee remains a significant clinical challenge, and clinical data are lacking. This study aimed to retrospectively determine the outcome of single-stage knee arthrodesis with a unilateral external fixator combined with cannulated screws for the treatment of end-stage TB.

Methods

Twenty-six patients with end-stage knee TB were treated by single-stage arthrodesis. All patients underwent open debridement and the insertion of a unilateral external fixator combined with crossed cannulated screws and received systemic antitubercular therapy. Clinical evaluations and radiographic analyses were performed after an average follow-up duration of 5.5 years.

Results

The mean time to radiographic bone fusion was 5.6 months. Primary full union was achieved in 25 patients (96.2 %) within 8 months, and the remaining patients achieved bone fusion at 14 months postoperatively. The mean post-operative alignment was 5.4° valgus and 12.5° flexion. The mean leg-length discrepancy was 2.8 cm. The mean VAS score improved from 67.3 before surgery to 16.2 at the last follow-up (P < 0.01), and the mean WOMAC score improved from 58.8 to 13.7 (P < 0.01). The erythrocyte sedimentation rate (ESR) and C-reactive protein level returned to normal in 25 patients by 3 months postoperatively. No recurrence in the target knee was noted.

Conclusions

Single-stage arthrodesis with a unilateral external fixator combined with cannulated screws can be regarded as efficacious for the treatment of end-stage knee TB. Additional studies are necessary to confirm the findings of our study.

Septic single-stage knee arthrodesis after failed total knee arthroplasty using a cemented coupled nail

Knee arthrodesis is a potential salvage procedure for limb preservation after failure of total knee arthroplasty (TKA) due to infection. In this study, we evaluated the outcome of single-stage knee arthrodesis using an intramedullary cemented coupled nail without bone-on-bone fusion after failed and infected TKA with extensor mechanism deficiency. Between 2002 and 2012, 27 patients (ten female, 17 male; mean age 68.8 years; 52 to 87) were treated with septic single-stage exchange. Mean follow-up duration was 67.1months (24 to 143, n = 27) (minimum follow-up 24 months) and for patients with a minimum follow-up of five years 104.9 (65 to 143,; n = 13). A subjective patient evaluation (Short Form (SF)-36) was obtained, in addition to the Visual Analogue Scale (VAS). The mean VAS score was 1.44 (SD 1.48). At final follow-up, four patients had recurrent infections after arthrodesis (14.8%). Of these, three patients were treated with a one-stage arthrodesis nail exchange; one of the three patients had an aseptic loosening with a third single-stage exchange, and one patient underwent knee amputation for uncontrolled sepsis at 108 months. All patients, including the amputee, indicated that they would choose arthrodesis again. Data indicate that a single-stage knee arthrodesis offers an acceptable salvage procedure after failed and infected TKA.

Advanced concepts in knee arthrodesis

The aim is to describe advanced strategies that can be used to diagnose and treat complications after knee arthrodesis and to describe temporary knee arthrodesis to treat infected knee arthroplasty. Potential difficult complications include nonunited knee arthrodesis, limb length discrepancy after knee arthrodesis, and united but infected knee arthrodesis. If a nonunited knee arthrodesis shows evidence of implant loosening or failure, then bone grafting the nonunion site as well as exchange intramedullary nailing and/or supplemental plate fixation are recommended. If symptomatic limb length discrepancy cannot be satisfactorily treated with a shoe lift, then the patient should undergo tibial lengthening over nail with a monolateral fixator or exchange nailing with a femoral internal lengthening device. If a united knee arthrodesis is infected, the nail must be removed. Then the surgeon has the option of replacing it with a long, antibiotic cement-coated nail. The authors also describe temporary knee arthrodesis for infected knee arthroplasty in patients who have the potential to undergo insertion of a new implant. The procedure has two goals: eradication of infection and stabilization of the knee. A temporary knee fusion can be accomplished by inserting both an antibiotic cement-coated knee fusion nail and a static antibiotic cement-coated spacer. These advanced techniques can be helpful when treating difficult complications after knee arthrodesis and treating cases of infected knee arthroplasty.

Arthrodesis of the knee following failed arthroplasty

PURPOSE

Primary stability in arthrodesis of the knee can be achieved by external fixation, intramedullary nailing or plate fixation. Each method has different features and results. We present a practical algorithm for arthrodesis of the knee following a failed (infected) arthroplasty, based on our own results and a literature review.

METHODS

Between 2004 and 2010, patients were included with an indication for arthrodesis after failed (revision) arthroplasty of the knee. Patients were analyzed with respect to indication, fusion method and bone contact. End-point was solid fusion.

RESULTS

Twenty-six arthrodeses were performed. Eighteen patients were treated because of an infected arthroplasty. In total, ten external fixators, ten intramedullary nails and six plate fixations were applied; solid fusion was achieved in 3/10, 8/10 and 3/6, respectively.

CONCLUSIONS

There is no definite answer as to which method is superior in performing an arthrodesis of the knee. Intramedullary nailing achieved the best fusion rates, but was used most in cases without--or cured--infection. Our data and the contemporary literature suggest that external fixation can be abandoned as standard fusion method, but can be of use following persisting infection. The Ilizarov circular external fixator, however, seems to render high fusion rates. Good patient selection and appropriate individual treatment are the key to a successful arthrodesis. Based upon these findings, a practical algorithm was developed.

Success of different knee arthrodesis techniques after failed total knee arthroplasty: is there a preferred technique?

Arthrodesis is a widely accepted treatment for failed total knee arthroplasty when further revision is contraindicated. In this study, we retrospectively review the pre-operative characteristics, operation techniques, treatment plans, and eventual outcomes in 42 consecutive patients (43 knees) who underwent knee arthrodesis at a single institution. Femorotibial fusion was achieved in 30 cases (75.0%). No cases of implant failure were recorded. Post-operative complications occurred in 20 cases (46.5%). Repeat arthrodesis was performed in 4 cases, and 2 patients eventually required above-the-knee amputation. Comparing the cases with successful vs. unsuccessful outcomes, there was a significant difference in days until hospital discharge following arthrodesis (P = .026), mean erythrocyte sedimentation rate prior to arthrodesis (P = .012), and the proportion of patients with post-operative wound complications (P = .021).

Outcome after knee arthrodesis for failed septic total knee replacement using a monolateral external fixator

PURPOSE

To evaluate the pain level and patient satisfaction as well as the fusion and infection eradication rates after knee arthrodesis using a monolateral external fixator for failed septic total knee replacement (TKR).

METHODS

Records of 10 male and 11 female consecutive patients aged 70 to 88 (mean, 81) years who underwent knee arthrodesis using a monolateral external fixator for failed septic TKR were retrospectively reviewed. Each patient had undergone a mean of 3.4 (range, 1-15) procedures. The infection eradication rate, fusion rate, time to achieve fusion, pain level, patient satisfaction, and health-related quality of life were evaluated.

RESULTS

Infection was eradicated in 18 (86%) of the 21 patients, whereas fusion was achieved in 17 (81%) of the 21 patients after a mean of 10.3 (range, 4-16) months. Those who did and did not achieve fusion differed significantly in terms of the mean pain score (2.3 vs. 6.4, p=0.031). Compared with age-matched Spanish general population, patients aged >75 years fared significantly worse in terms of the mean physical summary component score (40.7 vs. 34.9, p=0.001). Among those who achieved fusion, 82% were very or somewhat satisfied; none was very dissatisfied. Among those who did not achieve fusion, 75% were very or somewhat dissatisfied.

CONCLUSION

Knee arthrodesis using a monolateral external fixator for failed septic TKR achieved high fusion and infection eradication rates, despite the extended time needed. When fusion is achieved, patients had good pain relief and satisfaction.

Is there a role for knee arthrodesis with modular endoprostheses for tumor and revision of failed endoprostheses?

BACKGROUND

Knee arthrodeses are performed to treat infection after arthroplasty and tumors requiring extensive soft tissue resection. Many techniques have been described, but most have important disadvantages. Currently, endoprosthetic arthrodesis implants are available, but little is known about them.

QUESTIONS/PURPOSES

Our objective was to analyze a series of knee arthrodeses with a modular prosthetic system to evaluate (1) survivorship of the implant, (2) complications, (3) whether survivorship differed between arthrodeses done for primary tumor resection and revision reconstructions, and (4) whether survivorship differed based on the presence of previous infection or the use of a gastrocnemius flap.

METHODS

We present 32 patients with modular knee arthrodeses; arthrodeses were performed in 25 patients with tumors and in seven patients without tumors. There were 14 implants done at the time of tumor resection and 18 for revision of failed implants. Survivorship and complications were analyzed with Kaplan-Meier curves. Log-rank test was used for comparison between primary and revision implants, not infected and previously infected implants, and use or nonuse of a gastrocnemius flap.

RESULTS

Survivorship of arthrodeses with modular endoprostheses was 50% and 25% at 5 and 10 years, respectively. There were nine infections (29%) and one implant fracture (3%). Amputation as final surgery was required in 8 patients (six owing to infection and two to oncologic failures). There was no significant difference in survivorship between arthrodeses done for primary tumor resection and as a salvage procedure for failed implants. No differences were found between patients with and without prior infection or with and without a gastrocnemius flap.

CONCLUSIONS

Survivorship of a modular arthrodesis implant was 50% at 5 years owing to a high complication rate. Infection is the most common cause of failure of oncologic and revision implants. Implant fracture is a rare occurrence. Modular segmental arthrodesis provides a stable construct for patients in whom limb preservation is possible but a hinged device is contraindicated as a result of major muscle resection.

LEVEL OF EVIDENCE

Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Two-stage knee arthrodesis using a cemented modular tumour replacement system for recalcitrant septic proximal tibial non-union: a case report

Knee arthrodesis is an alternative to amputation for treating recalcitrant septic non-union of the proximal tibia with bone loss, soft-tissue compromise, and knee-joint involvement. Nonetheless, arthrodesis is difficult to achieve if bone loss is massive, and the septic environment can result in failed bone fusion. We report on a 77-year-old man with massive bone loss secondary to recalcitrant septic non-union who underwent radical bone resection, followed by knee arthrodesis using a cemented modular intercalary megaprosthesis in conjunction with a microvascularised flap in 2 stages.

Knee arthrodesis - ultima ratio for the treatment of the infected knee

The irretrievable destruction of the knee due to trauma, tumor or infection is the indication for knee arthrodesis. The main reason for knee arthrodesis in terms of infection ist the infected total knee arthroplasty. Central problem is the definition of the term "irretrievable". It is based on the subjective opinion of the attending physician and depends on his expert knowledge of this specific entity. The preservation of a functioning extremity is the main goal. This article shows the typical indications and contraindications for knee arthrodesis following septic knee diseases. In addition it gives insight into the biomechanical and technical considerations to be kept in mind. Finally the postoperative care and outcome of different techniques are analysed.

[Knee arthrodesis in rescue surgery: a study of 18 cases]

BACKGROUND

The aim of the study is evaluate the functional outcome, complications and general health in patients undergoing knee arthrodesis.

PATIENTS AND METHODS

Eighteen patients undergoing knee arthrodesis due to contraindication of primary or revision of a total knee arthroplasty (TKA). Anatomical arthrodesis was performed if there was a good contact of the two bone surfaces, whereas if it was not possible to achieve adequate femoral-tibial contact, artificial arthrodesis was performed. Function was assessed using the WOMAC score, and the health status using the SF-36.

RESULTS

Four patients were diagnosed with anatomical non-union arthrodesis and required a secondary surgical procedure to achieve fusion. Patients with artificial fusion did not have any secondary procedure. Patients less than 65 years-old and the patients with anatomical fusion had a better outcome in the physical role and body pain area using the SF-36 score. WOMAC index outcomes were similar in all patients, regardless of age and fusion type.

CONCLUSIONS

Anatomical and artificial arthrodesis of the knee achieved pain relief, acceptable function of the limb and an adequate quality of life, with the best results in patients less than 65 years-old.

Knee arthrodesis with a press-fit modular intramedullary nail without bone-on-bone fusion after an infected revision TKA

INTRODUCTION

Knee arthrodesis can be an effective treatment after an infected revision Total Knee Arthroplasty (TKA). The main hypothesis of this study is that a two-stage arthrodesis of the knee using a press-fit, modular intramedullary nail and antibiotic loaded cement, to fill the residual gap between the bone surfaces, prevents an excessive limb shortening, providing satisfactory clinical and functional results even without direct bone-on-bone fusion.

MATERIAL AND METHODS

The study included 22 patients who underwent knee arthrodesis between 2004 and 2009 because of recurrent infection following revision-TKA (R-TKA). Clinical and functional evaluations were performed using the Visual Analogue Scale (VAS) and the Lequesne Algofunctional Score. A postoperative clinical and radiographical evaluation of the residual limb-length discrepancy was conducted by three independent observers.

RESULTS

VAS and LAS results showed a significant improvement with respect to the preoperative condition. The mean leg length discrepancy was less than 1cm. There were three recurrent infections that needed further surgical treatment.

DISCUSSION

This study demonstrated that reinfection after Revision of total knee Arthroplasty can be effectively treated with arthrodesis using a modular intramedullary nail, along with an antibiotic loaded cement spacer and that satisfactory results can be obtained without direct bone-on-bone fusion.

Bridging knee arthrodesis for limb salvage using an intramedullary cemented nail: a retrospective outcome analysis of a case series

INTRODUCTION

Failed total knee replacement with compromised bone and soft-tissues can be challenging. In these situations, arthrodesis remains a treatment option of a limb-saving procedure.

METHODS

We investigated the outcome of treatment with an intramedullary cemented knee arthrodesis nail implanted in 22 consecutive patients with forlorn situations after failed total knee replacement.

RESULTS

There were three major complications due to re-infection and two minor complications due to wound-healing disturbances that healed with the implant retained after an average follow-up of 3.4 years. Clinical examination, Short Form-36 and Oxford knee scores revealed low pain levels, safe implant anchorage, and improved stability of the knee, whilst autonomous mobility utilizing walking aids was still possible.

CONCLUSION

Bridging knee arthrodesis with an intramedullary nail is a valuable salvage procedure with acceptable clinical results. As recurring infection remains the most challenging complication, regular clinical and radiological follow-up examinations are necessary following implant-related knee arthrodesis to allow timely intervention in case of loosening.

Distraction arthrodesis with intramedullary nail and mixed bone grafting after failed infected total knee arthroplasty

PURPOSE

The purpose of this study was to determine the success rate of the distraction arthrodesis, which was attempted to maintain the limb length during arthrodesis using an intramedullary nail and mixed bone grafting, in terms of the eradication of infection, solid union, and functional outcome. The hypothesis was that distraction arthrodesis would be successful in union and elimination of infection with minimal limb shortening and a satisfactory functional outcome despite large bone defects.

METHODS

Eight patients were managed by arthrodesis using a Huckstep intramedullary nail and massive corticocancellous bone chip grafts from autologous iliac bone and deep-frozen femoral head allografts were included in the study. The mean age of the patients was 65.5 ± 7.1 years, and the follow-up duration was 52.1 ± 21.3 months. A mean of 5.3 ± 1.3 surgical procedures had been performed before arthrodesis. The mean longest and shortest distances of the bone defect were 58.6 ± 10.3 and 34.6 ± 7.0 mm, respectively.

RESULTS

Radiological union was obtained in all cases at a mean of 9.9 ± 1.9 months. The mean postoperative limb shortening was 11.0 ± 7.3 mm when compared to the contralateral knee. The mean Knee Society score was 59.9 ± 9.2, and the function score was 38.8 ± 13.3. No additional procedures were required for any of the patients.

CONCLUSION

Distraction arthrodesis of infected knees following total knee arthroplasty demonstrated union and eradication of infection in all patients and a large tibiofemoral gap due to the severe bone defect could be managed with massive bone chip grafts. This method of arthrodesis would be a reliable and an effective method for failed total knee arthroplasty when two-staged reimplantation fails or is not attainable.

Knee joint transplantation combined with surgical angiogenesis in rabbits--a new experimental model

PURPOSE

We have previously described a means to maintain bone allotransplant viability, without long-term immune modulation, replacing allogenic bone vasculature with autogenous vessels. A rabbit model for whole knee joint transplantation was developed and tested using the same methodology, initially as an autotransplant.

MATERIALS/METHODS

Knee joints of eight New Zealand White rabbits were elevated on a popliteal vessel pedicle to evaluate limb viability in a nonsurvival study. Ten additional joints were elevated and replaced orthotopically in a fashion identical to allotransplantation, obviating only microsurgical repairs and immunosuppression. A superficial inferior epigastric facial (SIEF) flap and a saphenous arteriovenous (AV) bundle were introduced into the femur and tibia respectively, generating a neoangiogenic bone circulation. In allogenic transplantation, this step maintains viability after cessation of immunosuppression. Sixteen weeks later, X-rays, microangiography, histology, histomorphometry, and biomechanical analysis were performed.

RESULTS

Limb viability was preserved in the initial eight animals. Both soft tissue and bone healing occurred in 10 orthotopic transplants. Surgical angiogenesis from the SIEF flap and AV bundle was always present. Bone and joint viability was maintained, with demonstrable new bone formation. Bone strength was less than the opposite side. Arthrosis and joint contractures were frequent.

CONCLUSION

We have developed a rabbit knee joint model and evaluation methods suitable for subsequent studies of whole joint allotransplantation.

Knee arthrodesis using a vascularized fibular rotatory graft after tumor resection

INTRODUCTION

Knee arthrodesis is one of the reconstruction options for limb preservation after malignant tumor resection. Vascularised rotatory fibular transfer allows biological and, thus,definitive reconstruction. The goal of this work was to analyse the results of knee arthrodesis with vascularised fibular graft after tumor resection and to discuss the reliability of this technique.

PATIENTS AND METHODS

We report a retrospective series of 13 patients with an average age of 29.6 years. The pathological diagnosis was bone sarcoma in 12 cases and synovial chondrosarcoma in one case. Resection/arthrodesis was undertaken as the primary procedure in 11 cases.In two cases, arthrodesis was indicated after failure of an endoprosthesis. Reconstruction was achieved with a vascularised fibular rotatory transfer in all cases. For stabilisation, an external fixator was utilised in eight cases, a femorotibial nail in three cases, and a plate in two cases.Mean follow-up was 6 years.

RESULTS

We encountered infection in 53% of cases, mechanical complications in 53% of cases,and nerve palsy in 23% of cases. Four patients died from metastases (only one had arthrodesis complete union). In the nine surviving patients, arthrodesis was fully united in seven cases,after an average period of 36 months. The functional score average (Enneking classification)was 20 points.

DISCUSSION

Knee arthrodesis after tumor resection is a complex technique. Septic complications and mechanical failure are frequent regardless of the technique employed. They are related to the extent of bone sacrifice but also to that of soft tissues. The use of vascularised fibula alone and stabilisation by external fixation were the main shortcomings in this series. TYPE OF STUDY RETROSPECTIVE: Level IV.

Knee stabilisation following infected knee arthroplasty with bone loss and extensor mechanism impairment using a modular cemented nail

Infected Total Knee Replacement with significant bone loss and loss of extensor mechanism poses a difficult management problem. Arthrodesis relying on bony union can be difficult to achieve and can result in significant limb shortening. We retrospectively looked at the outcome of seven patients with significant bone loss and extensor mechanism insufficiency following infected TKR who underwent knee stabilisation using a modular cemented nail. The nail relied on the strong coupling mechanism between the modular femoral and tibial components. Pain score improved from a mean of 7.9 pre-operatively to 1.5 post-operatively at a mean follow up of 39.6 months (range 7-68) months. Two patients underwent technically easy revision nailing for recurrent infection and aseptic loosening. The Endo-Model(R) Knee Fusion Nail (Newsplint, UK/Waldemar Link, GmbH & Co. KG, Hamburg, Germany) has good early results in terms of pain relief and provides a stable knee in cases with significant bone loss and extensor mechanism insufficiency following an infected TKR thus avoiding an above knee amputation.

Use of bone morphogenetic proteins in arthrodesis: clinical results

Bone grafting is not routinely required in primary arthrodesis in the absence of infection, avascular necrosis, bone defect or previous non-union; when any of the above factors is present, autograft is the gold-standard method. However, donor site morbidity and the quantitative and qualitative limitations of autograft have led to the development of alternatives. This study documents the use of the bone morphogenetic protein BMP-7 in a total of 19 joint fusions (ankle, subtalar, talonavicular, pubic and sacroiliac). Healing rates of 90% and satisfactory subjective functional outcome in 70% of cases were recorded over a minimum follow-up of 15 months. These data should provide a sound foundation for future clinical trials evaluating the application of BMP-7 in the fusion of joints.

Innovative trident fixation technique for allograft knee arthrodesis for high-grade osteosarcoma around the knee

OBJECTIVE

Reconstruction for osteosarcoma around the knee after wide resection faces the challenge of great bone defect and future limb length discrepancy in the skeletally immature patients. Modern prosthetic reconstruction may provide good results, but the longevity may be of concern and may not be affordable in certain communities. Allograft knee arthrodesis still has its role in light of bone stock preservation and cost-effectiveness.

METHODS

We developed the innovative trident fixation technique utilizing three Steinmann pins to minimize limb length inequality without jeopardizing knee fusion stability. Twelve patients were enrolled. The mean age was 11.5 (10-13) years. Two had high-grade osteosarcoma in proximal tibia and others in distal femur.

RESULTS

Two patients died of oncological disease. The median follow-up of the disease-free 10 patients was 47 (41-60) months. All allograft-host bone junctions healed uneventfully without major complications except one allograft fracture. The average limb length discrepancy was 1.45 (1.0-2.1) cm at latest follow-up.

CONCLUSIONS

This straightforward technique was successful in knee arthrodesis with minimized limb length inequality. Accordingly, in light of bone stock preservation and longevity for the young children, it may be a surgical alternative for malignant bone tumors around the knee.