Arthrodesis of the ankle secondary to replacement

Outcomes of Total Ankle Arthroplasty After Periprosthetic Cyst Curettage and Bone Grafting

Total ankle arthroplasty (TAA) has become a popular management option for ankle arthritis. Periprosthetic osteolysis is one of the most common causes for reoperation in TAA. A CT scan should be done in all suspected osteolysis cases to confirm location, quantify size and aid in surgical planning. These patients are often asymptomatic with limited evidence regarding appropriate management. Smaller lesions should be monitored for progression in size. Periprosthetic cysts measuring 10-15mm in all three axes should be considered for debridment and curettage with autogenous bone grafting. The authors believe that bone grafting of large asymptomatic periprosthetic cysts could prevent implant failure.

Navigating the Challenges of Total Ankle Replacement: Deformity Correction and Infection Considerations

In recent years, total ankle replacement (TAR) has gained widespread acceptance as a surgical treatment for end-stage ankle arthritis. This shift is due to notable improvements in implant design, surgical instrumentation, technique, and surgeon expertise, resulting in high levels of patient satisfaction comparable to ankle fusion. Additionally, indications for TAR have expanded to include advanced deformities that were previously considered unsuitable for the procedure, making ankle arthrodesis the only option. Despite these advancements, TAR still carries a higher complication rate compared to other ankle surgeries. The complex anatomy of the ankle, coupled with limited soft tissue, presents significant challenges in managing complications associated with TAR.

Total Ankle Replacement Infections: A Systematic Review of the Literature

Periprosthetic infection (PJI) after TAR is a serious complication, often requiring further surgery, including revision arthroplasty, conversion to ankle arthrodesis, or even amputation. This systematic review aims to summarize the current evidence on the management of TAR PJI and provide a comprehensive overview of this topic, especially from an epidemiologic point of view. Three different databases (PubMed, Scopus, and Web of Science) were searched for relevant articles, and further references were obtained by cross-referencing. Seventy-one studies met the inclusion criteria, reporting on cases of TAR PJI. A total of 298 PJIs were retrieved. The mean incidence of PJI was 3.8% (range 0.2-26.1%). Furthermore, 53 (17.8%) were acute PJIs, whereas most of them (156, 52.3%) were late PJIs. Most of the studies were heterogeneous regarding the treatment protocols used, with a two-stage approach performed in most of the cases (107, 35.9%). While the prevalence of ankle PJI remains low, it is potentially one of the most devastating complications of TAR. This review highlights the lack of strong literature regarding TAR infections, thus highlighting a need for multicentric studies with homogeneous data regarding the treatment of ankle PJI to better understand outcomes.

Fusion after a failed primary total ankle arthroplasty

Aims

When a total ankle arthroplasty (TAA) fails, it can be converted to a fusion or a revision arthroplasty. Despite the increasing numbers of TAAs being undertaken, there is little information in the literature about the management of patients undergoing fusion following a failed TAA. The primary aim of this study was to analyze the survival of fusions following a failed TAA using a large dataset from the National Joint Registry (NJR).

Methods

A data linkage study combined NJR and NHS Digital data. Failure of a TAA was defined as a fusion, revision to a further TAA, or amputation. Life tables and Kaplan-Meier graphs were used to record survival. Cox proportional hazards regression models were fitted to compare the rates of failure.

Results

A total of 131 patients underwent fusion as a salvage procedure following TAA. Their mean age was 65.7 years (SD 10.6) and 73 (55.7%) were male. The mean follow-up was 47.5 months (SD 27.2). The mean time between TAA and fusion was 5.3 years (SD 2.7). Overall, 32 (24.4%) underwent reoperations other than revision and 29 (22.1%) failed. Of these 24 (18.3%) underwent revision of the fusion and five (3.8%) had a below-knee amputation. No patients underwent conversion to a further TAA. Failure usually occurred in the first three postoperative years with one-year survival of fusion being 96.0% (95% confidence interval (CI) 90.7 to 98.3) and three-year survival in 69 patients being 77.5% (95% CI 68.3 to 84.4).

Conclusion

Salvage fusion after a failed TAA shows moderate rates of failure and reoperations. Nearly 25% of patients required revision within three years. This study is an extension of studies using the same methodology reporting the failure rates and risk factors for failure, which have recently been published, and also one reporting the outcome of revision TAA for a failed primary TAA, using the same methodology, which will shortly be published.

Republication of "Total Ankle Replacement Conversion to Tibiotalocalcaneal Arthrodesis With Bulk Femoral Head Allograft and Pseudoelastic Intramedullary Nail Providing Sustained Joint Compression"

Tibiotalocalcaneal (TTC) arthrodesis is commonly performed to salvage a failed total ankle replacement. These salvage procedures are complicated by significant bone loss from the ankle replacement and are associated with low patient satisfaction. Here, we describe 2 cases of patients who presented with a failed total ankle replacement and underwent arthrodesis using a bulk femoral head allograft and a novel pseudoelastic intramedullary nail. The intramedullary nail contains an internal pseudoelastic element that adapts to bone resorption and settling allowing for compression to be maintained at the arthrodesis sites throughout healing. In the first case, a 65-year-old woman with a failed total ankle replacement underwent TTC arthrodesis. The second case involved an obese 53-year-old woman who had previously undergone 2 total ankle replacement procedures that resulted in unsuccessful outcomes. In both cases, union was demonstrated on computed tomographic scan by 6 months. At 2 years postsurgery, both patients were satisfied with the procedure. These cases provide preliminary evidence that tibiotalocalcaneal arthrodesis with a pseudoelastic IM nail and structural allograft is an appropriate treatment for failed total ankle replacements. Level of Evidence: Level IV, therapeutic, case series.

Management of Periprosthetic Bone Cysts After Total Ankle Arthroplasty

Modern improvements in total ankle arthroplasty (TAA) have increased the performance of this procedure for treatment of end-stage ankle arthritis. A common finding after TAA is the formation of periprosthetic bone cysts, which can be clinically silent or result in TAA failure. The exact cause of periprosthetic bones cysts has not been established, but major theories are related to osteolysis secondary to implant wear, micromotion, and stress shielding. Treatment can be nonoperative with clinical observation for small, asymptomatic cysts. Large, progressive, and symptomatic cysts often merit surgical treatment with debridement and grafting, revision TAA, or salvage arthrodesis.

Revision tibiotalar arthrodesis with posterior iliac autograft after failed arthroplasty: A matched comparative study with primary ankle arthrodeses

INTRODUCTION

Tibiotalar arthrodeses performed after failed ankle arthroplasties are known to be complex procedures with often disappointing functional outcomes. This study reports the results of a revision technique using a posterior iliac crest autograft.

HYPOTHESES

We hypothesized that: (1) revision tibiotalar arthrodeses (RTTAs) had functional outcomes which were similar to those of a reference cohort of primary tibiotalar arthrodeses (TTAs) and that (2) the union rate was satisfactory.

MATERIALS AND METHODS

This retrospective study compared 16 RTTAs performed for failed arthroplasties that caused pain and a functional disability (4 aseptic loosening, 4 massive progressive periprosthetic cysts, 5 malpositioning of implants, and 3 cases of unexplained mechanical pain) with a series of 16 primary TTAs performed for painful ankle osteoarthritis. The groups were matched at a 1:1 ratio for age, sex, side and body mass index. The preoperative workup included a physical exam, the American Orthopaedic Foot and Ankle Society (AOFAS) score, weight bearing radiographs, CT and SPECT scans. Outcomes were assessed both clinically (AOFAS score) and radiographically (X-rays and scans). The mean duration of the procedure (DP), average length of stay (LOS), fusion and complication rates, and time to union were also compared.

RESULTS

At the mean follow-up of 30 months (range, 12-88) for the RTTA group and 59 months (range, 23-94) for the TTA group (p=.001), the AOFAS score increased from 27 to 70.8 points (p<.001) and from 29.8 to 76.2 points (p<.001), respectively; values were similar at the last follow-up (p=.442). Both groups had similar fusion (94%) and complication rates (12%). The DP was 196.9±33.6min (range, 179-213) vs. 130±28.4min (range, 118-141) (p<.001) and the LOS was 3.8 days (range, 2-6) vs. 3.9 days (range, 2-6) (p<.445) for both groups (RTTA vs. TTA).

CONCLUSION

This RTTA technique using a posterior iliac crest allograft for filling bone defects was validated by the quality of the functional outcomes obtained.

LEVEL OF EVIDENCE

IV; Comparative retrospective study.

Utilization of the Pedicled and Free Fibula Flap for Ankle Arthrodesis

Ankle arthrodesis has become a common surgical procedure for individuals with end-stage ankle arthritis, chronic infection, and bony misalignment. Although arthrodesis is typically managed with arthrodesis in situ or realignment, reconstruction may be utilized for patients with more complicated cases that involve metatarsal defects. Our institution utilizes both the pedicled and free fibula flaps for surgical management pertaining to ankle arthrodesis. Our study looks to evaluate the work of a single plastic surgeon and identify patient postoperative outcomes.

The outcomes of revision surgery for a failed ankle arthroplasty

Aims

Revision rates for ankle arthroplasties are higher than hip or knee arthroplasties. When a total ankle arthroplasty (TAA) fails, it can either undergo revision to another ankle replacement, revision of the TAA to ankle arthrodesis (fusion), or amputation. Currently there is a paucity of literature on the outcomes of these revisions. The aim of this meta-analysis is to assess the outcomes of revision TAA with respect to surgery type, functional outcomes, and reoperations.

Methods

A systematic review was conducted using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. PubMed, Medline, Embase, Cinahl, and Cochrane reviews were searched for relevant papers. Papers analyzing surgical treatment for failed ankle arthroplasties were included. All papers were reviewed by two authors. Overall, 34 papers met the inclusion criteria. A meta-analysis of proportions was performed.

Results

Six papers analyzed all-cause reoperations of revision ankle arthroplasties, and 14 papers analyzed failures of conversion of a TAA to fusion. It was found that 26.9% (95% confidence interval (CI) 15.4% to 40.1%) of revision ankle arthroplasties required further surgical intervention and 13.0% (95% CI 4.9% to 23.4%) of conversion to fusions; 14.4% (95% CI 8.4% to 21.4%) of revision ankle arthroplasties failed and 8% (95% CI 4% to 13%) of conversion to fusions failed.

Conclusion

Revision of primary TAA can be an effective procedure with improved functional outcomes, but has considerable risks of failure and reoperation, especially in those with periprosthetic joint infection. In those who undergo conversion of TAA to fusion, there are high rates of nonunion. Further comparative studies are required to compare both operative techniques. Cite this article: Bone Jt Open 2022;3(7):596–606.

Pathogenesis, Evaluation, and Management of Osteolysis Following Total Ankle Arthroplasty

Periprosthetic osteolysis is a common occurrence after total ankle arthroplasty (TAA) and poses many challenges for the foot and ankle surgeon. Osteolysis may be asymptomatic and remain benign, or it may lead to component instability and require revision or arthrodesis. In this article, we present a current and comprehensive review of osteolysis in TAA with illustrative cases. We examine the basic science principles behind the etiology of osteolysis, discuss the workup of a patient with suspected osteolysis, and present a review of the evidence of various management strategies, including grafting of cysts, revision TAA, and arthrodesis.Level of Evidence: Level V, expert opinion.

Revision Surgery for Failed Total Ankle Replacement

Revision surgery for failed total ankle replacement is a challenge to the revision surgeon. Deformity, presence of infection, segmental bone defects, patient comorbidities, and soft tissue compromise all are significant considerations when determining appropriate procedures. Revision total ankle replacement, explant and fusion with or without lengthening, use of a trabecular metal cage, placement of an antibiotic cement spacer, grafting, and amputation all are viable options to treat patients with failed ankle arthroplasty.

Ankle Arthrodesis With Structural Grafts Can Work for the Salvage of Failed Total Ankle Arthroplasty

Background. Treatment options after failed total ankle arthroplasty (TAA) are limited. This study reports midterm outcomes and radiographic results in a single-surgeon group of patients who have undergone ankle arthrodesis with intramedullary nail fixation and structural allograft augmentation following failed TAA. Methods. A retrospective review on patients who underwent failed TAA revision with structural femoral head allograft and intramedullary tibiotalocalcaneal (TTC) nail fixation was completed. Foot Function Index (FFI), American Orthopaedic Foot & Ankle Society (AOFAS) outcome scores, and radiographs were obtained at each visit with 5-year follow-up. Results. Five patients were followed to an average of 5.2 years (range 4.7-5.6). Enrollment FFI was 34.82 (range 8.82-75.88); at midterm follow-up it was 20.42 (range 0-35.38). Enrollment AOFAS scores averaged 66.6 (range 61-77); at midterm follow-up it was 70.33 (range 54-88). Radiographs showed union in 4 of 5 patients at enrollment and 2 of 3 patients at midterm. Conclusions. Utilization of TTC fusion with femoral head allograft is a salvage technique that can produce a functional limb salvage. Our results show continued improvement in patient-reported outcomes, with preservation of limb length and reasonable union rate. Levels of Evidence: Therapeutic, Level II: Prospective, comparative trial.

Ankle fusion after failed ankle replacement in rheumatic and non-rheumatic patients

BACKGROUND

With longer follow-up, survival rate of total ankle replacements (TAR) diminishes. It is therefore important to have a reliable fall-back option in case of failed TAR. Revision arthroplasty is often impossible because of loss of bonestock or infection. Conversion to ankle fusion is then indicated. We investigated the clinical, radiographic and patient reported results for fusion after failed TAR in a consecutive group of patients. We concentrated on the influence of inflammatory joint disease (IJD) on union rate.

METHODS

Patient files and radiographic images of 46 consecutive patients (47 ankles) were reviewed. There were 22 patients with IJD. Fixation methods included; anterior plating, blade plate fixation, intramedullary nailing, compression screws and external fixation. Foot and Ankle Outcome Score (FAOS) and Foot and Ankle Ability Measure (FAAM) were used to determine patient related outcomes.

RESULTS

Forty out of 47 ankles (85%) Fused. Union rate in the non-IJD group (96%) was significantly higher compared to the IJD-group (73%, p=0.04). Revisions and complications were more frequent in the IJD group, but numbers were too small to detect a significant difference. Mean PROM scores were: FAOS-symptoms; 68.5, FAOS-pain; 70.3, FAOS-QoL; 43.7, FAOS-ADL; 68.1 and FAAM-ADL; 52.1, with no significant difference between IJD and non-IJD patients.

CONCLUSIONS

IJD-patients have a higher nonunion rate after ankle fusion for failed TAR. However, patient reported outcome is not significantly different between the two groups.

LEVEL OF EVIDENCE

IV, retrospective cohort.

Complications and results of the arthrodesis after total ankle arthroplasty failure: a retrospective monocentric study of 12 cases

INTRODUCTION

Total ankle arthroplasty (TAA) has the objective to maintain the range of motion of the tibiotarsal joint and to preserve the nearby joints. However, the complication rate and failures remain quite high after TAA. The main objective of the study was to evaluate the improvement in the functional scores of the tibiotarsal arthrodesis after TAA failure. The secondary objective was to assess the specific complications.

MATERIALS AND METHODS

This monocentric retrospective series includes 12 patients (nine men, three women, average age 52.5 years) operated between 2003 and 2018. An iliac graft was used in all cases. The arthrodesis was stabilized either by screws or by retrograde nailing.

RESULTS

The reoperation was due to painful malleolar conflicts or loosening. The AOFAS score increased from 38/100 to 67/100 (51-86) post-operatively. The fusion was acquired at 3.7 months (3-6) except in two cases.

DISCUSSION AND CONCLUSION

The 83% primary fusion rate is in the low average of the literature and 92% fusion rate in the high average after reoperation. All patients were improved even in two non-unions. The results of this study confirm that the arthrodesis after TAA failure is a reliable alternative to the TAA replacement. However, they are lower than those after a first-line arthrodesis.

Total Ankle Replacement Conversion to Tibiotalocalcaneal Arthrodesis With Bulk Femoral Head Allograft and Pseudoelastic Intramedullary Nail Providing Sustained Joint Compression

Tibiotalocalcaneal (TTC) arthrodesis is commonly performed to salvage a failed total ankle replacement. These salvage procedures are complicated by significant bone loss from the ankle replacement and are associated with low patient satisfaction. Here, we describe 2 cases of patients who presented with a failed total ankle replacement and underwent arthrodesis using a bulk femoral head allograft and a novel pseudoelastic intramedullary nail. The intramedullary nail contains an internal pseudoelastic element that adapts to bone resorption and settling allowing for compression to be maintained at the arthrodesis sites throughout healing. In the first case, a 65-year-old woman with a failed total ankle replacement underwent TTC arthrodesis. The second case involved an obese 53-year-old woman who had previously undergone 2 total ankle replacement procedures that resulted in unsuccessful outcomes. In both cases, union was demonstrated on computed tomographic scan by 6 months. At 2 years postsurgery, both patients were satisfied with the procedure. These cases provide preliminary evidence that tibiotalocalcaneal arthrodesis with a pseudoelastic IM nail and structural allograft is an appropriate treatment for failed total ankle replacements.

Level of Evidence:

Level IV, therapeutic, case series.

Revision of failed total ankle arthroplasty to a hindfoot fusion

Aims

The aim of this study was to present a series of patients with aseptic failure of a total ankle arthroplasty (TAA) who were treated with fusion of the hindfoot using a nail.

Patients and Methods

A total of 23 TAAs, in 22 patients, were revised for aseptic loosening and balloon osteolysis to a hindfoot fusion by a single surgeon (NH) between January 2012 and August 2014. The procedure was carried out without bone graft using the Phoenix, Biomet Hindfoot Arthrodesis Nail. Preoperative investigations included full blood count, CRP and ESR, and radiological investigations including plain radiographs and CT scans. Postoperative plain radiographs were assessed for fusion. When there was any doubt, CT scans were performed.

Results

The mean follow-up was 13.9 months (4.3 to 37.2). Union occurred at the tibiotalar joint in 22 ankles (95.6%) with one partial union. Union occurred at the subtalar joint in 20 ankles (87%) of cases with two nonunions. The nail broke in one patient with a subtalar nonunion and revision was undertaken. The only other noted complication was one patient who suffered a stress fracture at the proximal aspect of the nail, which was satisfactorily treated conservatively.

Conclusion

This study represents the largest group of patients reported to have undergone revision TAA to fusion of the hindfoot with good results Cite this article: Bone Joint J 2018;100-B:475–9.

Poor outcomes of fusion with Trabecular Metal implants after failed total ankle replacement: Early results in 11 patients

INTRODUCTION

One of the reasons for revision of total ankle replacement (TAR) implants is loosening due to subchondral cysts. Reconstruction and fusion of the ankle is often the first choice for revision procedures due to the large bone defects, which are typically filled with autograft and/or allograft. Filling the defect with a trabecular metal tantalum implant is a potential alternative given the biomechanical properties of this component.

HYPOTHESIS

Using tantalum as a spacer provides primary stability and contributes to fusion of the ankle joint after removal of failed TAR implants.

METHODS

Eleven patients underwent arthrodesis an average of 6.9 years after TAR. The mean height of the bone defect was 32mm. It was filled with a specially designed quadrangular implant (Trabecular Metal™, Zimmer/Biomet) combined with an iliac crest graft. Ten patients underwent tibio-talo-calcaneal (TTC) arthrodesis fixed with an angled retrograde nail and one patient underwent talocrural arthrodesis fixed with two plates (anterolateral and anteromedial). The clinical, functional (AOFAS and SF36 scores) and radiological (plain X-rays and CT scan) outcomes were determined.

RESULTS

At a mean follow-up of 19.3 months, the mean total AOFAS score was 56 (21-78) and the mean SF36 score was 60.5 (19-84). One patient was lost to follow-up and four patients still had pain. The tantalum implant was integrated in six patients. Five patients achieved fusion of the subtalar joint and 8 achieved fusion of the talocrural joint. Three patients required surgical revision.

DISCUSSION

Our hypothesis was not confirmed. The clinical outcomes after more than 1 year of follow-up are disappointing, as was the large number of nonunion cases and the lack of tantalum integration. These technical failures can be explained by insufficient construct stability and/or insufficient implant porosity.

LEVEL OF EVIDENCE

IV (retrospective cohort study).

[Aseptic loosening of total ankle replacement and conversion to ankle arthrodesis]

OBJECTIVE

To remove loosened prosthesis components, to perform augmentation, to address osseous defects, to perform neutrally aligned ankle arthrodesis, and to achieve postoperative pain relief.

INDICATIONS

Symptomatic, aseptic loosening of total ankle replacement (TAR) with/without substantial bone defect of the tibial and/or talar bone stock.

CONTRAINDICATIONS

General surgical or anesthesiological risks, periprosthetic infection, local or systemic infection, nonmanageable soft tissue problems.

SURGICAL TECHNIQUE

Removal of both prosthesis components using the previous incision (mostly using anterior ankle approach). Careful debridement of bone stock at the tibial and talar side. Osseous augmentation of defects using autologous or homologous cancellous bone, if needed, using structural allografts.

POSTOPERATIVE MANAGEMENT

A soft wound dressing is used. Thromboprophylaxis is recommended. Patient mobilization starts on postoperative day 1 with 15 kg partial weight bearing using a stabilizing walking boot or cast for 6-8 weeks. Following clinical and radiographic follow-up at 6 weeks, full weight bearing is initiated gradually after progressive osseous healing has been confirmed.

RESULTS

Between January 2007 and December 2012, ankle arthrodesis was performed in 9 patients with failed TAR (6 men and 3 women, mean age 56.4 ± 7.0 years, range 47.8-66.0 years). The mean time between the initial TAR and revision surgery was 4.5 ± 2.4 years (range 1.2-7.9 years). In one patient irrigation and debridement was performed due to superficial wound infection. Another patient had a delayed osseous healing 11 months after the revision surgery.

Evaluation and management of the painful total ankle arthroplasty

Total ankle arthroplasty (TAA) is an increasingly popular treatment option for patients with end-stage ankle arthritis. Although improved short- and long-term clinical and radiographic outcomes have been achieved with TAA, revision surgery may be necessary in the setting of aseptic loosening, subsidence, impingement, arthrofibrosis, or infection. Factors such as patient selection, implant design, and surgical technique can all contribute to TAA failure. Treatment of patients with a painful TAA is complex and requires careful consideration of symptom history, workup, and nonsurgical and surgical treatment options. Surgical management of failed TAA includes arthrodesis, revision surgery, or below-knee amputation.

Ankle arthrodesis after failed total ankle replacement: a systematic review of the literature

PURPOSE

As the number of total ankle replacements (TARs) performed has risen, so has the need for revision. The purpose of this investigation was to perform a systematic review of clinical outcomes following a salvage ankle arthrodesis from a failed TAR to identify patient- and technique-specific prognostic factors and to determine the clinical outcomes and complications following an ankle arthrodesis for a failed TAR.

METHODS

We searched PubMed, Medline, EMBASE, and the Cochrane Central Register of Controlled Trials for studies that analyzed ankle fusion after failed TAR with a minimum follow-up of 1 year.

RESULTS

We included 16 studies (193 patients). The majority of patients (41%) underwent the index TAR for rheumatoid arthritis. The majority of these revision surgeries were secondary to component loosening, frequently of the talar component (38%). In the cases that were revised to an ankle arthrodesis, 81% fused after their first arthrodesis procedure. The intercalary bone graft group and the blade plate group had the highest rate of fusion after the first attempt at fusion at 100%, whereas the tibiotalocalcaneal fusion with cage group had the lowest fusion rate at 50%. The overall complication rate was 18.2%, whereas the overall nonunion rate was 10.6%.

CONCLUSION

A salvage ankle arthrodesis for a failed TAR results in favorable clinical end points and overall satisfaction at short-term follow-up if the patients achieve fusion. The bone graft fusion and blade plate group resulted in the highest first-attempt fusion rate, with a low complication rate. Future studies should include prospective, comparative control or surgical groups and use standardized outcome measurements that will make direct comparisons easier.

LEVELS

Level IV: Systematic Review of Level IV Studies.

Inferior results of salvage arthrodesis after failed ankle replacement compared to primary arthrodesis

BACKGROUND

Up to now, there has been no evidence that salvage arthrodesis would perform inferior when compared with primary ankle arthrodesis. The purpose of this study was to compare their clinical and radiographic results.

METHODS

A retrospective analysis was performed using 2 validated scores and assessment of radiographic union by comparing 23 patients who underwent salvage ankle arthrodesis (group SA = salvage arthrodesis) after failed total ankle replacement with 23 matched patients who received primary ankle arthrodesis (group PA = primary arthrodesis). The mean follow-up period was 38 (range 16-92) months in group SA and 56 (23-94) months in group PA.

RESULTS

Complete union was achieved in 17 patients (74%) after a mean time of 50 (13- 114) weeks in group SA and in 16 patients (70%) after a mean time of 23 (10-115) weeks in group PA. The SF-36 score averaged 48 points (7-80) in SA and 66 points (14-94; P = .006) in group PA. In group SA the mean FFI was 57% (22-82) for pain and 71% (44-98) for function. In group PA significantly better results for pain with 34% (0-88; P = .002) and function with 48% (1-92; P = .002) were found.

CONCLUSION

Salvage arthrodesis led to impaired life quality and reduced function combined with significantly higher pain when compared with primary ankle arthrodesis. These findings can be used to counsel our patients preoperatively.

LEVEL OF EVIDENCE

Level III, retrospective case series.

Surgical tip: Titanium foam blocks can simplify fusion of failed total ankle replacements

Ankle arthrodesis following failed ankle replacements is a technically challenging task because of the large defect left behind after the prosthesis is removed. The usual practice is to use bulk grafts which are either autografts or allografts to fill the defect. We report our experience with the use of a titanium foam block specifically designed for fusion of failed ankle replacements. This particular method was chosen to avoid the technical difficulties and morbidities associated with the use of bulk autografts and allografts. We describe the surgical technique and early results in the first two cases performed in our unit. The satisfactory clinical and radiologic results in the two cases demonstrate the ability of the titanium foam block to simplify an otherwise complex procedure without compromising the outcome.

Retrograde Intramedullary Nail With Femoral Head Allograft for Large Deficit Tibiotalocalcaneal Arthrodesis

BACKGROUND

Large bone defects present a difficult task for surgeons when performing single-stage, complex combined hindfoot and ankle reconstruction. There exist little data in a case series format to evaluate the use of frozen femoral head allograft during tibiotalocalcaneal arthrodesis in various populations in the literature.

METHODS

The authors evaluated 25 patients from 2003 to 2011 who required a femoral head allograft and an intramedullary nail. The average time of final follow-up visit was 83 ± 63.6 weeks (range, 10-265).

RESULTS

Twelve patients healed the fusion (48%). Twenty-one patients resulted in a braceable limb (84%). Four patients resulted in major amputation (16%).

CONCLUSION

This series may allow surgeons to more accurately predict the success and clinical outcome of these challenging cases.

LEVEL OF EVIDENCE

Level IV, case series.

Arthrodesis After Failed Total Ankle Replacement

BACKGROUND

The literature on salvage procedures for failed total ankle replacement (TAR) is sparse. We report a series of 17 patients who had a failed TAR converted to a tibiotalar or a tibiotalocalcaneal arthrodesis.

METHODS

Between 2003 and 2012, a total of 17 patients with a failed TAR underwent an arthrodesis. All patients were followed on a regular basis through chart review, clinical examination and radiological evaluation. The following variables were analyzed: pre- and postoperative Meary angle, cause of failure, method of fixation, type of graft, time to union, complications, and postoperative American Orthopaedic Foot and Ankle Society (AOFAS) score. The average follow-up was 30.1 months. The average period from the original arthroplasty to the arthrodesis was 49.8 months.

RESULTS

Thirteen of the 17 ankles were considered radiographically healed after the first attempt in an average time of 3.7 months and 3 after repeat arthrodesis. Bone grafts were used in 16 patients. The median postoperative AOFAS score was 74.5. The mean Meary angle of the hindfoot was 5 degrees of valgus.

CONCLUSION

Tibiotalar and tibiotalocalcaneal arthrodeses were effective salvage procedures for failed TAR. Massive cancellous allografts were a good alternative to compensate for the large bone defect after removal of the prosthesis and to preserve the leg length.

LEVEL OF EVIDENCE

Level IV, retrospective case series.

Ankle arthritis: review of diagnosis and operative management

The diagnostic and therapeutic options for ankle arthritis are reviewed. The current standard of care for nonoperative options include the use of nonsteroidal antiinflammatory drugs, corticosteroid injections, orthotics, and ankle braces. Other modalities lack high-quality research studies to delineate their appropriateness and effectiveness. The gold standard for operative intervention in end-stage degenerative arthritis remains arthrodesis, but evidence for the superiority in functional outcomes of total ankle arthroplasty is increasing. The next few years will enable more informed decisions and, with more prospective high-quality studies, the most appropriate patient population for total ankle arthroplasty can be identified.

Tibiotalocalcaneal arthrodesis with bulk femoral head allograft for salvage of large defects in the ankle

BACKGROUND

Tibiotalocalcaneal arthrodesis in patients with large segmental bony defects presents a substantial challenge to successful reconstruction. These defects typically occur following failed total ankle replacement, avascular necrosis of the talus, trauma, osteomyelitis, Charcot, or failed reconstructive surgery. This study examined the outcomes of tibiotalocalcaneal (TTC) arthrodesis using bulk femoral head allograft to fill this defect.

METHODS

Thirty-two patients underwent TTC arthrodesis with bulk femoral head allograft. Patients who demonstrated radiographic union were contacted for SF-12 clinical scoring and repeat radiographs. Patients with asymptomatic nonunions were also contacted for SF-12 scoring alone. Preoperative, intraoperative, and postoperative factors were analyzed to determine positive predictors for successful fusion.

RESULTS

Sixteen patients healed their fusion (50% fusion rate). Diabetes mellitus was found to be the only predictive factor of outcome; all 9 patients with diabetes developed a nonunion. In this series, 19% of the patients went on to require a below-knee amputation.

CONCLUSIONS

Although the radiographic fusion rate was low, when the 7 patients who had an asymptomatic nonunion were combined with the radiographic union group, the overall rate of functional limb salvage rose to 71%. TTC arthrodesis using femoral head allograft should be considered a salvage procedure that is technically difficult and carries a high risk for complications. Patients with diabetes mellitus are at an especially high risk for nonunion.

LEVEL OF EVIDENCE

Level IV, retrospective case series.

Fusion following failed total ankle replacement

Although mid- to long-term results after total ankle replacement have improved because of available second- and third-generation devices, failure of total ankle replacement is still more common compared with total hip replacement and total knee replacement. The portfolio of available total ankle replacement revision component options is small. Furthermore, the bone stock of the tibiotalar region is scarce making it difficult and in some situations impossible to perform revision total ankle replacement. In these cases tibiotalar and tibiotalocalcaneal fusions are valuable options. This article describes which surgical procedures should be performed depending on the initial situation and gives detailed advice on surgical technique, postoperative care, and clinical results.

Salvage arthrodesis after failed ankle replacement: surgical decision making

Fusion remains the primary technique to salvage the failed total ankle. Fusions present a daunting challenge because of the large bone defect left by the explanted arthroplasty components and the difficulty obtaining stable fixation. Limiting the fusion to the tibiotalar joint preserves the essential motion of the hindfoot. However, because of loss of talar bone stock, it is often necessary to include the subtalar joint in a tibiotalocalcaneal fusion. This article discusses how to determine whether an isolated ankle or ankle-hindfoot fusion is indicated and presents surgical techniques for filling the bone defect and achieving stable internal fixation.

Circular external fixator-assisted ankle arthrodesis following failed total ankle arthroplasty

BACKGROUND

Failed total ankle arthroplasty (TAA) often results in significant bone loss and requires salvage arthrodesis. This study quantified the bone loss following failed TAA and reports the outcome of seven arthrodesis reconstructions using the Ilizarov method.

METHODS

A retrospective review of ankle fusions was performed for failed TAA to collect the mode of implant failure, presenting limb length discrepancy (LLD), total bone defect, postarthrodesis LLD, and treatment type (shoe lift versus distraction osteogenesis) and amount (shoe lift or lengthening).

RESULTS

Four mechanical failures and three infections were found. Four of seven cases had prior revision TAAs. Four of seven patients were treated with tibiotalar arthrodesis; three of the seven patients required talar resection and tibiocalcaneal arthrodesis. The mean presenting LLD was 2.2 (range, 1.2 to 3.5) cm. The mean time in frame was 197 (range, 146 to 229) days. With a mean postexplantation total bone defect of 5.1 (range, 3.7 to 8.5) cm, four of seven patients elected tibial lengthening following fusion [mean lengthening 4.6 (range, 2.5 to 8.0) cm; external fixation index (EFI) 42.6 (range, 16.5 to 55.6) days/cm)]. Three of seven patients were treated with a shoe lift [mean lift height 2.9 (range 2.5 to 3.2) cm]. There was no failure of fixation, refracture, or infection. All patients had a stable plantigrade foot and walked with minimal limp. Association for the Study and Application of the Method of Ilizarov (ASAMI) functional scores were six good and one fair. ASAMI bone scores were four excellent and three good.

CONCLUSIONS

Ankle arthrodesis following failed TAA results in large LLDs secondary to bone loss during implant failure and subsequent explantation. External fixation can produce an excellent fusion rate in complex, possibly infected, failed TAAs. Limb length equalization (by either distraction osteogenesis or shoe lift) provides a means of obtaining good functional outcomes following failed TAA.

Operative technique of two parallel compression screws and autologous bone graft for ankle arthrodesis after failed total ankle replacement

BACKGROUND

The management of failed total ankle replacement (TAR) depends on the primary indication, presence of infection, condition of adjacent joints, and available bone stock. In addition, the patient's expectations, age, and general health should also be taken into account.

METHODS

This article describes a technique of arthrodesis in failed TAR with two parallel screws inserted in opposite directions and autologous cancellous bone graft. Four patients were managed using this technique. The subtalar joint and both malleoli were preserved.

RESULTS

The average time for radiological union was 14.8 weeks. There were no hardware-related complications or infections. One patient developed subsequent subtalar arthritis and is waiting for subtalar joint fusion.

CONCLUSION

The results from this small series of patients suggest that arthrodesis following failed total ankle replacement with two parallel screws and bone graft may be an effective technique.

Tibio-talo-calcaneo fusion using a locked intramedullary compressive nail

We present the clinical results and outcomes of 30 consecutive patients (31 ankles) who have undergone tibio-talo-calcaneal arthrodesis using an intramedullary nail to achieve bony union. This was a prospective study and surgery was performed by the senior author in a single hospital. We achieved high levels of satisfaction and outcome via the AOFAS and SF-36 scoring systems. We propose that this method of arthrodesis is reliable and easily reproducible for patients with severe arthritis and bone loss at the ankle and subtalar joints.

Metal-reinforced cement augmentation for complex talar subsidence in failed total ankle arthroplasty

There are limited options for failed total ankle arthroplasty (TAA) with major talar bone loss and component subsidence. Surgical options for this condition include revision arthroplasty, salvage arthrodesis, or amputation. Revision arthroplasty generally has been considered in situations of loose components with minimal bone loss or use of expensive custom-fabricated prosthetic components with elongated stems. Historically, failure that involves major talar bone loss has been considered resistant to reconstruction, and responsive only to complex arthrodesis or amputation. In this report, we describe a unique method of restoring talar support and preserving ankle function after failed TAA with major talar bone loss and component subsidence. Talar reconstruction using metal-reinforced bone cement augmentation is combined with the Inbone (Wright Medical Technology, Inc., Arlington, TN) total ankle system to restore talar height and ligamentous support. This technique has been used successfully in the last 4 years for various patterns of talar bone loss and obviates the need for custom components. When successfully performed, the revision technique results in restoration of mechanical alignment, anatomic height, and component support, in addition to providing substantial symptomatic relief.

Salvage of failed total ankle arthroplasty with fusion using structural allograft and internal fixation

BACKGROUND

The current study presents our experience with conversion of failed TAA to fusion.

MATERIALS AND METHODS

A retrospective review of all failed total ankles converted to fusion from 1999 to 2009 was performed at our institution.

RESULTS

Twelve total ankles were converted to isolated ankle fusions (Group I) and 12 converted to ankle-hindfoot fusions (Group II). All isolated ankle fusions were stabilized with anterior plate and screws with one nonunion. Structural bone graft was used in ten of 12. Mean outcome scores using the AOFAS-Ankle/Hindfoot score and Maryland Foot Score improved from preoperative values of 43 ± 13 and 56.7 ± 14 to 67 ± 12 and 71.2 ± 16 postoperatively, respectively (p < 0.05). All Group II ankle-hindfoot fusion patients were fixed using either anterior plate and screws, intramedullary nail, or a combination nail:plate construct. All received structural allografts. Five patients developed nonunion including four subtalar nonunions Preoperative scores on the AOFAS-AHS and MFS were 48.8 ± 14 and 58.3 ± 14. Postoperative scores were 51.2 ± 17 for the AOFAS and 64.5 ± 14 for the MFS. These changes were not statistically significant. However, the difference in nonunions was significant, p < 0.05.

CONCLUSION

Failed total ankles can be successfully converted to fusion using structural bone graft and internal fixation. The primary risk appears to be nonunion of the subtalar joint when ankle-hindfoot fusion is required. We believe this risk can be decreased by using a separate approach for preparation of the subtalar joint.

Use of a trabecular metal implant in ankle arthrodesis after failed total ankle replacement

BACKGROUND AND PURPOSE

Arthrodesis after failed total ankle replacement is complicated and delayed union, nonunion, and shortening of the leg often occur-especially with large bone defects. We investigated the use of a trabecular metal implant and a retrograde intramedullary nail to obtain fusion.

PATIENTS AND METHODS

13 patients with a migrated or loose total ankle implant underwent arthrodesis with the use of a retrograde intramedullary nail through a trabecular metal Tibial Cone. The mean follow-up time was 1.4 (0.6-3.4) years.

RESULTS

At the last examination, 7 patients were pain-free, while 5 had some residual pain but were satisfied with the procedure. 1 patient was dissatisfied and experienced pain and swelling when walking. The implant-bone interfaces showed no radiographic zones or gaps in any patient, indicating union.

INTERPRETATION

The method is a new way of simplifying and overcoming some of the problems of performing arthrodesis after failed total ankle replacement.

Salvage arthrodesis for failed total ankle arthroplasty

BACKGROUND AND PURPOSE

Total ankle arthroplasty (TAA) has gained popularity in recent years. If it fails, however, salvage arthrodesis must be reliable as a rescue procedure. We therefore investigated the clinical, radiographic, and subjective outcome after salvage arthrodesis in a consecutive group of patients, and concentrated on the influence of the method of fixation on union rate and on salvage in inflammatory joint disease.

PATIENTS AND METHODS

Between 1994 and 2005, salvage arthrodesis was performed on 18 ankles (18 patients). Diagnosis was inflammatory joint disease (IJD) in 15 cases and osteoarthritis (OA) in 3. Tibio-talar fusion was performed in 7 ankles, and tibio-talocalcaneal fusion in 11. Serial radiographs were studied for time to union. Clinical outcome at latest follow-up was measured by the AOFAS score, the foot function index (FFI) and by VAS scores for pain, function, and satisfaction.

RESULTS

Blade plates were used in 7 ankles (4 IJD, 3 OA); all united. Nonunion developed in 7 of the 11 rheumatic ankles stabilized by other methods. 11 patients (8 fused ankles, 3 nonunions) were available for clinical evaluation. Their mean AOFAS score was 62 and mean overall FFI was 70. VAS score for pain was 20, for function 64, and for satisfaction 74. The scores were similar in united and non-united ankles.

INTERPRETATION

Blade plate fixation is successful in salvage arthrodesis for failed TAA. A high nonunion rate was found after salvage ankle arthrodesis in IJD with other methods of fixation. Clinical results were fair to good.

Can porous tantalum be used to achieve ankle and subtalar arthrodesis?: a pilot study

A structural graft often is needed to fill gaps during reconstructive procedures of the ankle and hindfoot. Autograft, the current gold standard, is limited in availability and configuration and is associated with donor-site morbidity in as much as 48%, whereas the alternative allograft carries risks of disease transmission and collapse. Trabecular metal (tantalum), with a healing rate similar to that of autograft, high stability, and no donor-site morbidity, has been used in surgery of the hip, knee, and spine. However, its use has not been documented in foot and ankle surgery. We retrospectively reviewed nine patients with complex foot and ankle arthrodeses using a tantalum spacer. Minimum followup was 1.9 years (average, 2 years; range, 1.9-2.4 years). Bone ingrowth into the tantalum was analyzed with micro-CT in three of the nine patients. All arthrodeses were fused clinically and radiographically at the 1- and 2 year followups and no complications occurred. The American Orthopaedic Foot and Ankle Society score increased from 32 to 74. The micro-CT showed bony trabeculae growing onto the tantalum. Our data suggest tantalum may be used as a structural graft option for ankle and subtalar arthrodesis. All nine of our patients achieved fusion and had no complications. Using tantalum obviated the need for harvesting of the iliac spine.

LEVEL OF EVIDENCE

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

Ankle arthrodesis

Numerous techniques for ankle arthrodesis have been reported since the original description of compression arthrodesis. From the early 1950s to the mid 1970s, external fixation was the dominant technique utilized. In the late 1970s and 1980s, internal fixation techniques for ankle arthrodesis were developed. In the 1990s, arthroscopic ankle arthrodesis was developed for ankle arthrosis with minimal or no deformity. The open technique is still widely used for ankle arthrosis with major deformity. For complex cases that involve nonunion, extensive bone loss, Charcot arthropathy, or infection, multiplanar external fixation with an Ilizarov device, with or without a bone graft, may achieve successful union. The fusion rate in most of the recently published studies is 85% or greater, and may depend on the presence of infection, deformity, avascular necrosis, and nonunion.

The present state of ankle arthroplasty

BACKGROUND

Total ankle arthroplasty (TAA) is being carried out with increasing frequency and manufacturers are releasing new implant designs each year.

METHODS

We comment on the various designs and the outcome of the procedure as reported in the literature. No results have so far been published on the majority of the more recent designs and where outcome data are available, the follow up period is very short.

RESULTS

For those designs where 5 or 10 year follow-up studies have been performed, the survivorship at 5 years is over 90% in most instances and of the order of 80% at 10 years. The failure rate is lower in ankles that are well aligned at presentation than it is for those with more than 15 degrees varus or valgus deformity pre-operatively.

CONCLUSIONS

TAA has definite advantages over fusion for some patients and if selection criteria are adhered to, a long-lasting satisfactory outcome can be achieved.

[Short-term results after STAR total ankle replacement]

BACKGROUND

This retrospective study was performed to investigate the clinical and radiological results after STAR total ankle replacement.

MATERIAL AND METHODS

Between January 2000 and September 2004, 49 patients with an average age of 62.5 years underwent total ankle replacement with the STAR prosthesis. At an average follow-up of 30.4 months, 48 patients were examined clinically and radiologically. The Kofoed ankle score and the patients' subjective satisfaction were evaluated.

RESULTS

The operation improved the Kofoed ankle score significantly, from 28 to 86 points, 90% of the patients were satisfied with the results. The revision rate was 10%.

CONCLUSION

The early results after implantation of the STAR ankle prosthesis are encouraging. With correct indication, a high rate of pain reduction and patient satisfaction can be achieved. The long-term benefit of this procedure has yet to be determined.

Ankle arthrodesis: the simple and the complex

Ankle arthrodesis is by no means a simple surgery. It requires preoperative planning, meticulous preparation of bony surfaces, cognizance of ankle positioning, and rigidity of fixation. The procedure also requires enough experience on the part of the operating surgeon to recognize important patient factors and to determine which type of ankle arthrodesis is most appropriate for that specific patient.

A technique of fusion for failed total replacement of the ankle

Salvage of a failed total ankle replacement is technically challenging and although a revision procedure may be desirable, a large amount of bone loss or infection may preclude this. Arthrodesis can be difficult to achieve and is usually associated with considerable shortening of the limb.

We describe a technique for restoring talar height using an allograft from the femoral head compressed by an intramedullary nail. Three patients with aseptic loosening were treated successfully by this method with excellent symptomatic relief at a mean follow-up of 32 months (13 to 50).

Unsuccessful use of a titanium mesh cage in ankle arthrodesis: a report on three cases operated on due to a failed ankle replacement

Three patients with a failed total ankle arthroplasty underwent tibiocalcaneal arthrodesis. In an attempt to preserve leg length, a titanium cage filled with autologous bone was placed in the defect. None of the ankles healed primarily. After 9 to 29 months, the cages, which only contained necrotic material, were removed and repeat arthrodesis was performed using a retrograde intramedullary nail. After this procedure, 1 ankle had healed after 14 months whereas 2 did not heal. However, after a third attempt, using external fixation, 1 of the latter 2 healed. The method used in this report cannot be recommended. Although titanium mesh cages filled with autograft have been successfully used to substitute for vertebral defects, the author does not feel that the method can be recommended for ankle arthrodesis.

Arthrodesis after failed total ankle replacement

We present a series of 16 patients treated between 1993 and 2006 who had a failed total ankle replacement converted to an arthrodesis using bone grafting with internal fixation. We used tricortical autograft from the iliac crest to preserve the height of the ankle, the malleoli and the subtalar joint. A successful arthrodesis was achieved at a mean of three months (1.5 to 4.5) in all patients except one, with rheumatoid arthritis and severe bone loss, who developed a nonunion and required further fixation with an intramedullary nail at one year after surgery, before obtaining satisfactory fusion. The post-operative American Orthopaedic Foot and Ankle Society score improved to a mean of 70 (41 to 87) with good patient satisfaction. From this series and an extensive review of the literature we have found that rates of fusion after failed total ankle replacement in patients with degenerative arthritis are high. We recommend our method of arthrodesis in this group of patients. A higher rate of nonunion is associated with rheumatoid arthritis which should be treated differently.

The Swedish Ankle Arthroplasty Register: An analysis of 531 arthroplasties between 1993 and 2005

BACKGROUND

Whether or not ankles can be replaced with reasonable safety has been the subject of debate. We present the results of a nationwide series of total ankle arthroplasties.

PATIENTS AND METHODS

All Swedish hospitals that implant or have implanted modern three-component ankle prostheses reported demographic data and date of index and revision surgery to a central register. After the data had been introduced into a database, prosthetic survival rates with exchange or permanent extraction of components as endpoint were calculated.

RESULTS

Of the 531 prostheses implanted, 101 had been revised by June 15, 2006. The overall survival rate at 5 years was 0.78 (95%CI: 0.74-0.82). For the three surgeons who had inserted the majority of the STAR ankles, the survival rates became significantly higher after the first 30 cases had been performed and was estimated to be 0.86 (0.80-0.93) at 5 years. Lower age at index surgery implied increased risk of revision whereas diagnosis or gender did not.

INTERPRETATION

Ankle replacement is a valuable alternative to arthrodesis. However, replacing an ankle is a demanding procedure and the survival is not comparable to that after hip or knee replacement. It is obvious that with increasing experience, the results -- including prosthetic survival -- will improve.

[Long-term behavior of ankle fusion: assessment of the same series at 7 and 23 year (19-36 years) follow-up]

PURPOSE OF THE STUDY

Theoretically, long-term functional and radiographic degradation is predictable after ankle fusion, but sound evidence from the consecutive analysis of the same cohort is lacking. The purpose of this study was to check the hypothesis by repeating assessment in the same cohort of patients who underwent ankle fusion.

MATERIAL AND METHODS

The cohort included 52 ankle fusions which had been analyzed in 1984 at seven years (range 2-22 years) follow-up then again in 2000 using the same evaluation criteria. Among the 52 patients, six were lost to follow-up (11.5%) 20 had died (38.4%) and one had undergone leg amputation. The second analysis thus included 25 patients (48%). The comparison cohort thus included 25 patients (18 men and 7 women), mean age 62+/-12.6 years (range 40-94) at the 2000 assessment performed 23+/-4.5 years (range 19-36 years) after the fusion. Functional outcome was assessed with the 100-point Duquennoy scale. Osteoarthritis of the subtalar and mediotarsal joints were assessed preoperatively and at follow-up using the same scale.

RESULTS

The functional outcome did not deteriorate significantly between 1984 and 2000. The mean score was 65.8+/-22.6 (range 19-92) in 1984 and 64.7+/-18.3 (range 34-90) in 2000 (p=0.67). Fifteen patients (60%) had a good or very good outcome at seven years, and 14 (56%) at 23 years. Between 1984 and 2000, ten patients improved their score (on average 10.4 points, range 1-21 points), two had an unchanged score and thirteen a lower score (on average 10 points, range -1 to -24). Ten of these thirteen patients developed severe intercurrent conditions (neurological or cardiac) explaining the degradation. At last follow-up, sixteen ankles were pain free or nearly pain free. Twelve patients considered their ankle as a forgotten problem (VAS 10) and had no regrets concerning the operation. The evolution of the subtalar joint in 16 cases (nine fusions including five at the same time as the ankle fusion and four performed within four years) showed that all developed osteoarthrtic degradation early with aggravation between 1984 and 2000, leading in the majority of cases to severe degenerative disease. This osteoarthritis was painful in less than one-third of the cases (including the four secondary subtalar fusions and the four subtalar fusions which were painful at mobilization). Twenty-three mediotarsal joints were analyzed (two fusions four years after ankle fusion). The degradation was later and less severe than for the subtalar joint with a majority showing moderate osteoarthritis. Ten ankles exhibited compensatory hypermobility of the forefoot measured at more than 15 degrees without pain.

DISCUSSION

This long-term follow-up with two successive assessments using the same evaluation criteria did not demonstrated the late degradation of function expected after ankle fusion. It did show however the presence of undeniable radiographic degradation of the subtalar joint but with little or no severe clinical expression at a minimal follow-up of 19 years. There was no need for complementary fusion between 4 and 23 years follow-up.

The management of failed ankle replacement

Advances in the design of the components for total ankle replacement have led to a resurgence of interest in this procedure.

Between January 1999 and December 2004, 16 patients with a failed total ankle replacement were referred to our unit. In the presence of infection, a two-stage salvage procedure was planned. The first involved the removal of the components and the insertion of a cement spacer. Definitive treatment options included hindfoot fusion with a circular frame or amputation. When there was no infection, a one-stage salvage procedure was planned. Options included hindfoot fusion with an intramedullary nail or revision total ankle replacement. When there was suspicion of infection, a percutaneous biopsy was performed. The patients were followed up for a minimum of 12 months.

Of the 16 patients, 14 had aseptic loosening, five of whom underwent a revision total ankle replacement and nine a hindfoot fusion. Of the two with infection, one underwent fusion and the other a below-knee amputation. There were no cases of wound breakdown, nonunion or malunion.

Management of the failed total ankle replacement should be performed by experienced surgeons and ideally in units where multidisciplinary support is available. Currently, a hindfoot fusion appears to be preferable to a revision total ankle replacement.