Addressing non-unions involves stabilizing the affected area through osteosynthesis and improving bone biology using bone grafts. However, there is no consensus on the optimal treatment method. This study aims to compare outcomes of non-union surgery using conventional treatment methods (metal hardware ± graft) versus osteosynthesis with the human allogeneic cortical bone screw (Shark Screw®) alone or in combination with a metallic plate. Thirty-four patients underwent conventional treatment, while twenty-eight cases received one or more Shark Screws®. Patient demographics, bone healing, time to bone healing, and complications were assessed. Results revealed a healing rate of 96.4% for the Shark Screw® group, compared to 82.3% for the conventionally treated group. The Shark Screw® group exhibited a tendency for faster bone healing (9.4 ± 3.2 vs. 12.9 ± 8.5 weeks, p = 0.05061). Hardware irritations led to six metal removals in the conventional group versus two in the Shark Screw® group. The Shark Screw® emerges as a promising option for personalized non-union treatment in the foot, ankle, and select lower leg cases, facilitating effective osteosynthesis and grafting within a single construct and promoting high union rates, low complications, and a rapid healing process.

Ankle arthrodesis (AA) provides reliable pain relief, good patient satisfaction scores, and improved overall function. However, this procedure has been associated with numerous complications and sequelae, such as pseudoarthrosis, malunion, gait abnormalities, increased demand on surrounding joints, and a long period of convalescence. Conversion to total ankle arthroplasty (TAA) is a potential option in the management of these complex and challenging situations. The purpose of this study is to investigate the outcomes of AA conversion to TAA. A systematic review of electronic databases was performed. Six studies involving 172 ankles met inclusion criteria. The weighted mean preoperative Visual Analogue Scale (VAS) score at the time of TAA conversion was 7.8 and the weighted mean postoperative VAS score at the time of final follow-up was 2.5. The weighted mean preoperative AOFAS score at the time of TAA conversion was 32 and the weighted mean postoperative AOFAS score at the time of final follow-up was 72.4. The rate of salvage tibiotalocalcaneal arthrodesis was 2.3% and rate of transtibial amputation was also 2.3% after attempted conversion from initial AA to TAA. Conversion of AA to TAA appears to be a viable option to improve patient outcomes and prevent extensive hindfoot arthrodesis and transtibial amputation. More prospective studies with consistent reporting of outcomes, complications, and revision rates with long-term follow-up are needed.

Non-union is a regular complication of arthrodeses. Standard treatment includes revision surgery with frequent need for re-revision due to persistent non-union. Particularly patients with concomitant diseases are at risk of secondary complications. There is a need for evaluation of alternative treatment options. The aim of this study is to provide first evidence on union-rate and pain course after focussed extracorporeal shock-wave therapy of arthrodesis non-unions.

In a retrospective single-centre study, 25 patients with non-union following arthrodesis received one session of focussed extracorporeal shock-wave therapy (energy flux density 0.36 mJ/mm², 3000 impulses, 23 kV, 4 Hz). Radiographic and clinical results were recorded 6, 12 and 24 weeks after treatment.

24 patients were followed-up. After 24 weeks arthrodeses of the hand healed in 80%, of the upper ankle in 50%, of subtalar joint in 27.2% and of the midfoot in 0% of the cases. Pain decreased from 4.8 (± 2.8) points on the visual analogue scale to 3.4 (± 2.3), 2.9 (± 2.5) and 2.4 (± 2.8) points after 6, 12 and 24 weeks, respectively (p < 0.0001).

Our data indicate that the effect of focussed, high-energy shock wave therapy depends on body region and is effective for the treatment of non-unions of the hand as well as for pain relief.

Level IV.

Ankle arthrodesis is a common treatment used for patients with end-stage ankle arthritis (ESAA). The surgical goal of ankle arthrodesis is to obtain bony union between the tibia and talus with adequate alignment [slight valgus (0°-5°)], neutral dorsiflexion, and slight external rotation positions) in order to provide a pain-free plantigrade foot for weightbearing activities. There are many variations in operative technique including deferring approaches (open or arthroscopic) and differing fixation methods (internal or external fixation). Each technique has its advantage and disadvantages. Success of ankle arthrodesis can be dependent on several factors, including patient selection, surgeons' skills, patient comorbidities, operative care, etc. However, from our experience, the majority of ESAA patients obtain successful clinical outcomes. This review aims to outline the indications and goals of arthrodesis for treatment of ESAA and discuss both open and arthroscopic ankle arthrodesis. A systematic step by step operative technique guide is presented for both the arthroscopic and open approaches including a postoperative protocol. We review the current evidence supporting each approach. The review finishes with a report of the most recent evidence of outcomes after both approaches and concerns regarding the development of hindfoot arthritis.

Although conversion of the painful ankle arthrodesis to total ankle arthroplasty remains controversial, this surgical modality has satisfactorily expanded the treatment armamentarium for addressing this pathology.

Preoperative preparation and planning is similar to that for a primary total ankle arthroplasty, and implants designed for primary arthroplasty can be used in most patients managed with conversion to total ankle replacement.

Position the patient as for a primary total ankle replacement.

Preserve exsanguination time by removing hardware prior to inflating the tourniquet.

Recreate the native joint line, which can be relatively easy in selected patients and challenging in others.

Set the optimal talar slope, which can be challenging, particularly when the ankle arthrodesis is malunited in equinus.

Because the former medial and lateral articulations between the talus and the malleoli can be difficult to define, use careful surgical technique to avoid compromise of the malleoli and excessive talar resection.

To avoid potential malleolar fractures, mobilize the ankle only after the prophylactic malleolar screws have been placed; the tibial and talar cuts, completed; the gutters, reestablished; all resected bone, removed; and scar tissue from the posterior aspect of the ankle, excised; thereafter, conversion total ankle arthroplasty is similar to a primary total ankle replacement, with the exception of potential bone defects where prior hardware was positioned.

Perform the routine steps for primary total ankle arthroplasty, often ignoring bone defects from the ankle arthrodesis hardware, but plan to repair the defects with bone-grafting before implanting the final talar component.

Perform tibial preparation in a manner similar to that used for primary total ankle arthroplasty.

We performed 23 conversion total ankle arthroplasties in patients who had an ankle arthrodesis, including those with pain despite successful fusion and those with painful nonunions⁹.

Background Nonunion of an ankle arthrodesis is associated with significant pain and morbidity. Revision arthrodesis presents greater short-term morbidity and long-term sequelae. 1-6 Recent reports have demonstrated the feasibility of converting a symptomatic nonunion of an ankle arthrodesis to a total ankle arthroplasty.7-9 The objective of the present study was to evaluate the short-term outcome associated with take down of symptomatic nonunions of ankle arthrodeses and conversion to a fixed bearing, intramedullary total ankle arthroplasty. Methods Five patients with symptomatic, aseptic tibiotalar arthrodesis nonunions (average age, 62.2 years), who underwent conversion to a total ankle arthroplasty were retrospectively identified and assessed at a prospective office visit. Minimum follow-up was 12 months (average, 21.3 months). Clinical outcomes were assessed on the basis of the American Foot and Ankle Society (AOFAS) ankle-hindfoot score10 and the Foot Function Index.11,12 Radiographic analysis, patient satisfaction and pain levels were also evaluated. Results The average post-operative AOFAS ankle-hindfoot score was 82.6, while the FFI was 28.2%. The average clinical range of motion was 35 degrees. Visual analog scale (VAS) pain scores averaged 31.1 out of 100. Four out of the five patients were very satisfied or satisfied. Radiographically, the tibial and talar components were stable in all patients without evidence of loosening, migration, or subsidence. There were no complications requiring additional procedures. Conclusions Patients undergoing ankle arthrodesis that is complicated by an aseptic nonunion pose a difficult clinical problem. Conversion to a total ankle arthroplasty with a fixed bearing, intramedullary implant is a viable treatment option with reliable short-term results.

Therapeutic, Level IV: Case series.

Arthrodesis is a common operative procedure used to manage arthritis and deformity in the foot and ankle. Nonunion is a possible and undesirable outcome in any arthrodesis surgery. Rates of nonunion in the foot and ankle literature range from 0% to 47% depending on the patient population and joint involved. Multiple factors can contribute to developing a nonunion including location, fixation method, tobacco use, diabetes, infection, and others.

The case logs of 3 foot and ankle surgeons were reviewed from January 2007 to September 2014 to identify nonunion arthrodesis revision cases. The patient factors reviewed included diabetes, inflammatory arthropathy, tobacco use, history of infection, nonunion elsewhere, neuropathy, Charcot arthropathy, posttraumatic arthritis, and prior attempt at revision arthrodesis at the same site. Operative records were reviewed to identify location of the nonunion, instrumention, use of allograft or autograft bone, use of iliac crest bone marrow aspirate (ICBMA) and use of orthobiologics such as bone morphogenetic protein (BMP) during the revision arthrodesis. Successful revision was defined as radiographic union on the final radiograph during follow-up. Eighty-two cases of revision arthrodesis were identified with an average follow-up of 16 months.

The overall nonunion rate was 23%. Neuropathy and prior attempts at revision were identified as significant risks (P <.05) for persistent nonunion. Odds ratio calculated based on previous attempts at revision arthrodesis found a 2.8-fold increase in the risk of failure for each attempt at revision.

Revision arthrodesis for nonunion in the foot and ankle was successful (77%) under a variety of patient and operative conditions. Neuropathy was a significant patient risk factor for persistent nonunions, and we believe it is important to identify even in the nondiabetic patient. As the number of attempts at revisions increases, there is a subsequent 3-fold increase in the risk of persistent nonunion.

Level IV, case series.

Tibiotalocalcaneal arthrodesis is used to manage end stage arthritis, often associated with severe bone loss. The goal is to relieve pain through a stable, well-aligned hindfoot and ankle. We describe our initial results and outcome of ankle and tibiotalocalcaneal arthrodesis using a 90° blade plate.

We retrospectively reviewed the records of patients managed at our institution between 2010 and 2014. Twenty cases were identified who had either talocrural (n = 9) or TTC fusion (n = 11) with 1 patient having both ankle and then TTC fusion in separate sittings.

Fusion occurred in 18 of the 20 cases (90%) with correction of angular deformity and restoration of hindfoot alignment. None of the 18 patients developed complications and all discharged to follow-up when independently mobile and satisfied with the outcome.

This study demonstrated that using a 90° blade plate for ankle or TTC arthrodesis in a diverse group of complex primary and revision indications associated with severe deformity and bone loss resulted in a high rate of bony union and stable deformity correction.

While autogenous cancellous iliac crest bone graft is the gold standard for foot and ankle surgery, it lacks Level I evidence. Although one third of all graft cases performed in the United States today rely on allograft, some surgeons believe no graft is necessary. We hypothesized that a systematic review of the foot and ankle literature would reveal that (1) autogenous bone graft during foot and ankle arthrodesis would demonstrate healing rates that were superior to the use of either using allograft or no bone graft at all, and (2) these differences would be even more dramatic in patients having risk factors that impair bone healing. To our knowledge, neither of these assessments to date has ever been performed with this body of literature. The goal of this study was to review the use and union rates of bone graft during foot and ankle arthrodesis and determine if autogenous bone graft was superior.

A literature search was performed to include articles between 1959 and 2012 using autograft, allograft, and/or no bone graft for foot and/or ankle arthrodesis. Case reports involving fewer than four patients, investigations failing to incorporate outcome data, those involving orthobiologic augmentation, and those including vascularized graft, xenograft, or pediatric patients were excluded. Recorded search results included patient demographics, comorbidities, pre-operative diagnosis, surgical procedure, bone graft type and indication, union rate, method of fixation, patient satisfaction, all outcome scores, definition of healing/success, and any listed complications including revision. Final data were stratified based upon the type of graft material.

This search generated 953 related articles, of which 159 studies (5327 patients) met inclusion criteria. The majority (153/159) were retrospective case series. Systematic review demonstrated a trend toward higher union rates for cancellous autograft (OR 1.39, p=0.11), structural autograft (OR 1.52, p=0.09), and cancellous allograft (OR 1.31, p=0.52) relative to no graft material, but none reached statistical significance. Compared to no graft, structural allograft trended toward worse performance (OR 0.62, p=0.17). The overall probability of union was 93.7% for cancellous autograft, 94.2% for structural autograft, 93.3% for cancellous allograft, 91.4% for no graft, and 86.9% for structural allograft. When only comparing the 19 papers that included a no graft arm (91.9% union rate), data revealed the highest union using cancellous autograft (95.1%, OR 1.73, p=0.09) and structural autograft (96.3%, OR 2.33, p=0.06) while only 76% for structural allograft. No significant statistical association existed between union rates and other recorded variables.

Systematic analysis of bone graft use in foot and ankle fusions favors the use of autograft and cancellous allograft for optimized healing rates, although no differences were statistically significant. If we assume that graft material been chosen for more complex procedures having lower anticipated union rates, then these data lend further support to the use of autograft and cancellous allograft.

Level IV.

Open ankle arthrodesis is one of the primary operations for disabling ankle arthrosis. The transfibular lateral approach to ankle fusion is a common approach for open ankle arthrodesis. Autologous bone graft can be harvested from the osteotomised fibula. We describe a safe technique of taking graduated slices of fibula bone graft, which allows optimal fibula length excision and are suitable in shape to pack into defects at the fusion site.

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.

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.

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.

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 IV, retrospective case series.

To report 18 patients who underwent tibiotalocalcaneal arthrodesis using a retrograde intramedullary nail or cannulated screws.

10 men and 8 women (19 ankles) aged 36 to 70 (mean, 52) years underwent tibiotalocalcaneal arthrodesis using a retrograde intramedullary nail (n=13) or cannulated screws (n=6). Indications for arthrodesis were severe cavovarus deformity secondary to polio or charcot-marie-tooth disease (n=7), severe osteoarthritis in the ankle and subtalar joints (n=6), Charcot joint deformity (n=3), failed fusion procedures (n=2), and foot drop secondary to T12 tumour surgery (n=1). The visual analogue score (VAS) for pain was assessed, as were the American Orthopaedic Foot and Ankle Society (AOFAS) scores (for subjective and objective pain, function, and stability of the ankle), short form 36 (SF-36), and patient expectation and satisfaction scores.

The mean follow-up period was 35.6 (range, 11-144) months. 13 of 18 patients returned for assessment of scores. 18 of the 19 ankles achieved fusion after a mean period of 5.9 (range, 3-11) months. The mean VAS scores for pain, AOFAS scores, and SF-36 scores all improved. 11 patients had good-to-excellent satisfaction and expectation scores. Two patients had severe wound infections and underwent implant removal (after bone union), debridement, and intravenous antibiotic therapy. Two other patients had superficial wound infections. One patient with retrograde intramedullary nailing had a pseudoarthrosis and underwent implant removal, redebridement, re-autografting, and cannulated screw fixation. Fusion was achieved subsequently.

Tibiotalocalcaneal arthrodesis improved the pain score and quality of life, despite a high risk of complications.

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.

Arthrodesis is the most common procedure used to treat end-stage osteoarthritis of the ankle, particularly in patients with difficult conditions such as poor bone quality. While many techniques are available to fuse the ankle, current recommendations favor the use of internal fixation with screws and/or plates. Despite of progress, the complication rate remains a major concern. Non-union is one difficult problem especially with difficult bone conditions, particularly the loss of bone stock on the talar side. Therefore, fusion of the tibiotalar joint is often extended to the talocalcaneal joint to provide sufficient stability. To preserve the subtalar joint, an anterior double plate system for rigid fixation of isolated tibiotalar arthrodesis was developed. This is a preliminary report on the clinical and radiological outcome with this technique.

Twenty-nine patients (15 men, 14 women; one ankle per patient) were treated from October 2006 to September 2007. We converted 16 ankles with osteoarthritis and difficult bone conditions, four non-united ankle arthrodeses, and nine failed total ankle replacements to an isolated tibiotalar arthrodesis using anterior double plating. If necessary, we used solid allograft to fill bony defects. Outcomes included bone union as assessed by radiographs, pain as indicated by the American Orthopaedic Foot and Ankle Society scores, and patient satisfaction.

Solid arthrodesis was achieved after an average of 12.3 (eight to 26) weeks in the 16 ankles without bone graft interposed between the tibia and talus, and 14.3 (range, 8 to 26) weeks in the 13 ankles with interpositional bone allograft. Radiographs showed that the position of arthrodesis obtained at the time of surgery did not change in any patient up to one year after surgery. The mean American Orthopaedic Foot and Ankle Society (AOFAS) Hindfoot Score increased from 37 (range, 20 to 63) preoperatively to 68 (range, 50 to 92) at the last followup. Twenty-seven patients (93%) were satisfied with their outcome and indicated they would have the operation again. No complications were noted.

The anterior double plating system was shown be a reliable method to achieve solid isolated tibiotalar arthrodesis, even in ankles with difficult conditions such as loss of bone stock due to failed total ankle arthroplasty.

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.

Tibiotalocalcaneal arthrodesis is a successful and proven surgical procedure for patients who have significant arthritic changes, deformity, and failed previous operations. Surgical technique varies depending on the type of fixation. Basic surgical principles should not be violated. Correction of the deformity with appropriate joint preparation and stable fixation is important for a good outcome. Other adjunctive materials, such as bone growth stimulators and orthobiologics, should be used appropriately to ensure adequate primary arthrodesis.

Contemporary recommendations for primary and revision ankle arthrodesis favor internal compression techniques involving the use of screw and/or plate fixation. While tibiotalocalcaneal arthrodesis with internal fixation may be a suitable method of salvage for the treatment of a failed tibiotalar arthrodesis in selected patients, ring external fixation has been reported as an alternative. We reviewed our experience with revision tibiotalar arthrodesis, with a focus on ring external fixation.

Forty-five consecutive patients underwent revision tibiotalar arthrodesis with use of repeat internal fixation (eleven patients), ring external fixation (twenty-two patients), or tibiotalocalcaneal arthrodesis (twelve patients). Union rates were assessed radiographically, and functional outcome was determined with use of preoperative and postoperative American Orthopaedic Foot and Ankle Society ankle-hindfoot scores.

All forty-five patients were available for follow-up at an average of 50.3 months. The average ankle-hindfoot score improved from 31.1 points preoperatively to 65.8 points at the time of the most recent follow-up. At the time of the most recent follow-up, the union rate was 88.9% (forty of forty-five). Fusion was achieved with revision tibiotalar arthrodesis in thirty-six (80%) of forty-five patients, including eight of the eleven patients in the repeat internal fixation group, nineteen of the twenty-two patients in the ring external fixation group, and nine of the twelve patients in the tibiotalocalcaneal arthrodesis group. Re-revision led to union in four of five patients. The overall union rate for ring external fixation, including revision and re-revision tibiotalar arthrodeses, was 84.6% (twenty-two of twenty-six). The five patients with persistent nonunion following revision ankle arthrodesis opted for transtibial amputation.

Revision tibiotalar arthrodesis leads to satisfactory limb salvage in a majority of patients. Ring external fixation may facilitate clinically acceptable limb salvage in complex cases when methods of internal fixation are limited or even contraindicated.

Many operative techniques have been described for ankle arthrodesis, with varying fusion rates. In revisions, the fusion rate is lower than in primary arthrodesis. Recent reports have described good results after Ilizarov ankle arthrodesis. However, descriptions were qualitative, with none using an accepted score. We describe our experience with this technique and functional outcomes in our patients.

Seventeen patients (average age 48 years) had primary or revision unilateral ankle arthrodesis using the Ilizarov technique at two centers. Diagnoses included post-traumatic arthritis and Charcot arthropathy. Three patients had talar osteonecrosis. Time in the frame averaged 15 weeks and in a cast 4 weeks. Followup averaged 6 years. Outcome was assessed using the American Orthopaedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot Scale.

All ankles achieved solid fusion. The average AOFAS score was 65 out of 86 possible. Based on this, results were defined as excellent in three patients, good in eight, fair in four, and poor in two. Minor complications were common, all resolving with local treatment. No deep infection developed. One fusion malunited in 8 degrees of varus.

The Ilizarov external fixator has numerous advantages applicable to ankle fusion, including: stable fixation, respect for soft tissues, and the possibility of postoperative alignment 'fine-tuning'. Additionally, the ability to direct forces through or around skeletal elements allows varying of the load through the skeletal elements, allowing early weightbearing. The Ilizarov technique, with its high union rate, may be considered for any ankle arthrodesis but is especially useful in complex cases such as revisions, talar osteonecrosis, soft-tissue compromise, and infection. Early weightbearing is an added benefit.

Combined ankle and subtalar arthritis is a difficult problem for which there are varied solutions. Each solution has its advantages and disadvantages. Treatment must be specifically tailored to the patient's needs, comorbidities, and expectations. Because of the complicated nature of this condition and its treatment, complications are common and should be anticipated.

Several methods of obtaining ankle fusion have been described, with numerous studies reporting on patient populations with varied diagnoses and various methods of fixation. This has led to outcome analyses that are difficult to interpret. Our hypothesis is that using a standard method of fusion, without the aid of allograft, a solid ankle fusion can be achieved in patients with end-stage ankle arthritis, and that this outcome can be reflected in standardized outcome tools. Forty-one consecutive ankle fusions in 40 patients were included in our study, with a minimum followup of 3 years. All patients had an ankle arthrodesis using two parallel retrograde 7.3-mm screws and local fibular graft. All but two patients obtained a solid talocrural union (95%), with a mean postoperative improvement in the American Orthopaedic Foot and Ankle Society score of 23 points. Results of our study showed that a simple technique based on sound mechanical and biologic principles can yield excellent outcomes for patients.

Malunion and nonunion of an ankle fusion site are associated with pain, osteomyelitis, limb-length discrepancy, and deformity. The Ilizarov reconstruction has been used to treat these challenging problems.

We reviewed the results in twenty-one ankles that had undergone a revision of a failed fusion, with simultaneous treatment of coexisting pathologic conditions, with use of the Ilizarov technique. Eight patients had undergone ankle fusion only, eleven had undergone ankle and subtalar fusion, and two had undergone pantalar fusion. Eighteen patients with an average limb-length discrepancy of 4 cm underwent limb lengthening simultaneously with the revision surgery. The average patient age was forty years. Indications for treatment were malunion (eleven patients), aseptic nonunion (eight patients), and infected nonunion (two patients). Clinical, subjective, objective, gait, and radiographic analyses were performed after an average duration of follow-up of 83.4 months.

Solid union was achieved in all ankles. The functional result was excellent for fifteen patients, good for three, fair for two, and poor for one. The bone result was excellent for ten ankles, good for nine, fair for one, and poor for one. All eighteen patients who underwent gait analysis had a heel-to-toe progression gait, and twelve achieved normal walking velocity with their shoes on. A plantigrade foot was achieved in each case, and only two patients had >5 degrees of residual deformity. During the Ilizarov treatment, forty-one minor complications (treated conservatively) and twenty major complications (treated surgically) occurred. After removal of the circular frame, seven other complications, which required four additional operations, occurred.

In patients with a failed ankle fusion, infection, limb-length discrepancy, and foot deformity can be addressed simultaneously with use of the Ilizarov apparatus to achieve a solid union and a plantigrade foot, usually with a clinically satisfactory result.

AVN of the talus is a challenging disease process with respect to patho-physiology and treatment. We believe that our algorithm is a legitimate approach to aid the orthopedic surgeon in initiating a promising treatment. It is divided into different levels and allows to change between some. This is not the only way to proceed but it seems promising, especially if the long-term results with the vascularized bone grafts show revascularization of the talus. As always in medicine, the treatment needs to be individualized. Arthrodesis always should be the last option and is a challenging procedure.

Previously failed procedures with less than optimal outcomes always are distressing to the patient and surgeon. The revisional arthrodesis may require a higher level of surgical technique and skill than the original procedure from which it was derived. Another level of difficulty is added when the original procedure was deemed to have failed secondary to poor patient compliance. The basic tenets of successful revisional arthrodesis include a motivated and educated patient, adherence to basic surgical principles and techniques, and the ability to extrapolate those principles and techniques into ideas that are born from thinking along the lines of necessity.

From 1989 to 1996, we treated 18 cases (10 males, eight females; average age 48.2 years) of failed ankle arthrodesis by revision of ankle arthrodesis and followed their progress for at least two years. The average time interval between original surgery and revision was 17.3 months. Revisions were needed due to infection in one case, nonunion in 10 cases, and malalignment in seven cases. The salvage operations included debridement in the infected case, refreshed pseudoarthrosis in nonunion cases, and corrective osteotomy in malalignment cases. Sixteen cases were fixed by crossed screws with internal compression, one infected case was fixed by an external fixator, and one case with bone loss was fixed with buttress plate. The average follow-up period was 40.4 months. There was one nonunion and two delayed unions, with an ultimate fusion rate of 94%. The average AOFAS ankle-hindfoot score was 70.9 at final follow up. There was one excellent result (5.6%), five good results (27.8%), 11 fair results (61%), and one poor result (5.6%), and the overall results were poorer compared with our series of primary arthrodesis. The time to fusion also took longer in the revision cases (average 2.7 months in primary cases and 4.8 months in revision cases). Fusion techniques that ensure solid union in a functional position are essential. If an ankle arthrodesis fails, however, revision is a salvage procedure that can achieve an acceptable result.

The purpose of this study was to compare the compression effect of the 7.0-AO screw and the 6.5 mm Ideal Compression Screw (I.CO.S.) screw in an in vitro subtalar arthodesis model. Six fresh-frozen, human cadaver foot specimens were obtained for analysis. The subtalar joint was opened laterally without affecting the articular surfaces. ATekscan 5051 sensor with a maximum pressure of 250 PSI and a sensel-density of 62 sensel/sq-cm was placed into the joint, which allowed for continuous measurement of the contact area and contact forces achieved by one 7.0 AO-screw, and thereafter by one 6.5 I.CO.S.-screw. When tightening the screw, mean contact area increased by 0.21 cm2 for the AO-screw (p<0.05), and by 0.27 cm2 for the I.CO.S.-screw (p>0.05). When comparing the tightened AO-screw and I.CO.S.-screw, mean contact area increased from 1.40 cm2 to 1.97 cm2 (p<0.05). The mean contact force also increased when tightening the screws. This increase was 7.6 N for the AO-screw (p<0.05) and 14.8 N for the I.CO.S.-screw (p>0.05). When comparing the tightened AO-screw and I.CO.S.-screw, mean contact force increased from 54.9 N to 81.7 N (p<0.05). The obtained results have shown that the design of the screw influences the achieved compression force. The superior compression of the I.CO.S.-screw might be explained by the better gripping and additional compression mechanism of its head. The shape of the head of the cannulated AO-screw, in contrast, may be critical to resist against the weak cortical bone of the calcaneus, i.e. it can sink into soft bone resulting in a loss of compression force.

Arthrodesis has remained the mainstay for treating arthritis and deformities of the ankle and hindfoot for more than a century. Formidable technical challenges exist in achieving a successful result, leading to numerous complications as high as 50% in some series. The most frequent complications after tibiotalar and tibiotalocalcaneal arthrodesis involve nonunion, malunion, infection, and wound complications among others. Meticulous preoperative consideration for the technical and biologic issues involved may lead to diminished complication rates. With advances in implant technology, revision arthrodesis can, in most cases, be expected to yield outcomes comparable with those of a primary procedure. Algorithms for the treatment of the most frequent complications are presented.

Primary osteoarthritis of the ankle is a rare entity. Osteoarthritis of the ankle more commonly is seen secondary to trauma of the articular surface involving the normal biomechanics of the ankle. The causes are many and treatment consists of prevention of additional deterioration or treatment of that deterioration. The patient with osteoarthritis is plagued by chronic pain and decreased function. The surgical option for treatment includes soft tissue and bony debridement, ligamentous reconstruction, corrective osteotomy, arthrodesis, arthroplasty, or a combination of those treatments. The surgical treatment options are discussed and guidelines are provided for the treatment of ankle arthritis based on current concepts reported in the literature.