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

Outcomes of cobalt-chrome 3D-printed total talus replacement with and without combined total ankle replacement

BACKGROUND

Collapse of the talus and peri-talar arthritis pose treatment challenges due to the anatomy and location of the talus as a keystone of the foot and ankle. Custom 3D-printed total talus replacement (TTR) and combined total ankle total talus replacement (TATTR) have emerged as treatment options for these pathologies. However, the safety and efficacy of these implants is unknown due to the limited number of cases and short follow-up durations.

METHODS

This was a retrospective study to assess surgical outcomes of patients who underwent a TTR and TATTR with or without subtalar fusion. Patient demographics, intraoperative parameters, device related surgical and non-surgical events, imaging and clinical evaluations, and patient reported outcome (PRO) measures were compiled.

RESULTS

A total of 38 patients received a custom 3D-printed implant with mean follow-up time of 22.1 (range: 12-45) months. In this cohort, 7 (18.4 %) required secondary surgery and 3 (7.9 %) required implant removal. Multivariate logistic regression revealed that patient diagnosis of depression was a significant predictor of secondary surgery with an OR 17.50 (p = 0.037). Significant postoperative improvements were observed in the talocalcaneal height (p = 0.005) and talar declination angle (p = 0.013) for the TATTR group. VAS and PROMIS pain interference (PI) scores demonstrated an initial significant improvement in pain, but this improvement did not maintain significance at most recent follow-up. However, there was a significant increase in the PROMIS physical function (PF) scores (p = 0.037) at most recent follow-up.

CONCLUSION

These results demonstrate that TTR and TATTR provide significant improvement in post-operative radiographic foot and ankle alignment and physical function at the two-year timepoint. PRO findings suggest that patients are more active after surgery. Surgeons considering proceeding with either of these procedures should counsel patients about pain and functional outcomes as well as realistic expectations in patients with depression.

LEVEL OF EVIDENCE

Level 3.

Limb Salvage by Means of Hindfoot Arthrodesis Utilizing Bulk Allograft and External Fixation

FORMAT

Retrospective Review.

LENGTH OF FOLLOW-UP

18 months.

CLASSIFICATION

Rearfoot and Ankle Reconstruction.

METHODOLOGY

Level 4 Retrospective Review.

PROCEDURES

A retrospective review was performed of 6 patients who had undergone limb salvage procedures between January 2016 and April 2019. Patients underwent surgery due to severe limb-threatening diagnosis including Charcot and/or osteomyelitis. Salvage arthrodesis was performed with bulk femoral head allograft incorporation using a hexapod external fixation system. The external fixation was retained for an average of 16 weeks. All patients were followed for a postoperative period of 16 months.

RESULTS

Successful rearfoot arthrodesis and limb salvage was achieved in ⅚ (83%) of patients.

DISCUSSION

This review demonstrates that limb salvage and arthrodesis are possible using femoral head allograft incorporation by external fixation alone. The involved patients had resolution of the osteomyelitis and Charcot deformity, salvage arthrodesis of the rearfoot and avoidance of a major limb amputation.

LEVELS OF EVIDENCE

IV.

Outcomes of Tibiotalocalcaneal Arthrodesis vs Talar Body Prosthesis as Treatment of Collapsed Avascular Necrosis of the Talus: A 10- to 13-Year-Follow-up Retrospective Comparative Study

BACKGROUND

Joint salvage surgeries such as tibiotalocalcaneal arthrodesis and talar prosthesis are commonly used in the surgical treatment of collapsed avascular necrosis of the talus (AVNT). However, differences in outcomes of these 2 surgical treatments are still inconclusive. This study compared the 10- to 13-year outcomes and 10-year survivorship rates of tibiotalocalcaneal arthrodesis and talar body prosthesis in the surgical treatment of collapsed AVNT.

METHODS

A retrospective comparative study was conducted of patients who underwent either tibiotalocalcaneal arthrodesis or talar body prosthesis implantation between 2005 and 2012. The demographic matching process resulted in 24 patients per treatment group. Clinical outcomes were evaluated using a numeric rating scale (NRS) of 2 hours of activities of daily living (ADL) and Foot and Ankle Ability Measure (FAAM) for ADL. Radiographic assessments included the incidence of nonunion, adjacent joint arthritis, and prosthesis loosening. The 10-year survivorship of both surgical treatments was calculated. A P value of less than .05 was considered statistically significant.

RESULTS

The median NRS of 2 hours of ADL and FAAM score for ADL were statistically significantly better in the talar body prosthesis group, with P values of .001 and <.001, respectively. The statistically significant differences in FAAM score for ADL exceeded the minimum clinically important difference. In the tibiotalocalcaneal arthrodesis group, nonunion was observed in 7 of 24 patients (29.2%). No prosthesis loosening was reported in the talar body prosthesis group. The 10-year survivorship was statistically significantly higher in talar body prosthesis than tibiotalocalcaneal arthrodesis (95.8% vs 70.8%), P = .023.

CONCLUSION

Talar body prosthesis implantation in selected eligible patients demonstrated statistically significantly better 10- to 13-year clinical outcomes and higher 10-year survivorship compared with tibiotalocalcaneal arthrodesis in the surgical treatment of collapsed AVNT.

LEVEL OF EVIDENCE

Level III, retrospective cohort comparative study.

Tibiotalocalcaneal arthrodesis with an intramedullary nail: The functional and clinical outcome of a challenging patient group and its comparison to a below knee amputation

BACKGROUND

Tibiotalocalcaneal arthrodesis (TTCA) is a salvage procedure to fuse the ankle and subtalar joints to treat severe ankle and hindfoot disease. Patients often have multiple operations before a TTCA. A below knee amputation (BKA) has major physical and psychological impacts. Our aim is to investigate the outcomes of these treatments in salvage situations, with a focus on objective functional measurements and patient reported outcome measures (PROMs).

METHODS

52 patients underwent TTCA with a retrograde intramedullary nail and contacted for clinical and functional assessments and compared to patients who underwent traumatic BKA. PROMS such as AOFAS score, SF-36 and foot function index (FFI), and objective functional outcome measures were used.

RESULTS

Of the 52 TTCA patients, 28 patients were recruited for follow-up. 35.7% of patients had postoperative complications. Mean postoperative AOFAS score was 63.9 ± 8.4 (range, 47-81), FFI 48.8 ± 15.8 (range, 22.2-75.2). 11 BKA patients (mean age 46.4 years) were included as control group. BKA patients scored higher than the TTCA patients on SF-36 physical functioning (p < 0.01) and SF-36 mental health (p < 0.05) subscales. The flat-surface functional tests (timed up and go test, 2-minute walk test, 10-meter walk test) showed significantly (p < 0.05) better outcomes for the BKA compared to TTCA.

CONCLUSIONS

A TTCA is a salvage procedure with high complication rates. Functional and psychometric results are reduced compared to the normal population. Patients after a BKA had significantly better scores on SF-36 functional and mental health subscales and better functional outcomes for flat ground activities compared to TTCA. Heterogeneity of the TTCA and BKA patient cohorts is a limitation of this study. With these results in mind, the outlook of a BKA is not necessarily a grim one. They may be used by surgeons to counsel patients preoperatively when managing complex ankle and hindfoot disease.

LEVEL OF EVIDENCE

Level III, retrospective cohort study.

Preliminary Experience With Commercially Available Trabecular Metal Tibial Cones Combined With a Retrograde Locked Intramedullary Nail for Bony Defects in Tibiotalocalcaneal Arthrodesis

Critical sized bone defects in the ankle are becoming increasingly more common in patients undergoing limb reconstruction with tibiotalocalcaneal arthrodesis. Bulk allografts have not fared well over time. There have been scattered preliminary reports using custom spinal cages or 3D-printed Titanium Implants to address the critical bony defect; however, the cost of these devices is prohibitive in many clinical practice settings. The purpose of this investigation is to report the preliminary experience using a commercially available Trabecular Metal (Zimmer-Biomet) tibial metaphyseal cone combined with a retrograde locked intramedullary nail to address this challenging problem. Eight consecutive patients underwent tibiotalocalcaneal arthrodesis using a commercially available Trabecular Metal tibial metaphyseal cone combined with a retrograde locked intramedullary nail. Five developed bone loss secondary to neuropathic (Charcot) bony resorption and 3 underwent surgery for failed total ankle arthroplasty. All 8 patients eventually achieved clinical and radiographic healing and were able to ambulate with standard footwear. One patient developed a postoperative wound infection at the site of calcaneal locking screws, which resolved with debridement and parenteral antibiotic therapy. Critical bone defects about the ankle have successfully addressed with custom 3D titanium implants. This small series suggests that similar clinical outcomes can be achieved with the use of a commercially available porous tantalum metaphyseal spacer borrowed from our arthroplasty colleagues, combined with the use of a retrograde locked intramedullary nail.Levels of Evidence: Level 4: Retrospective case series.

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.

The use of a 3D printed titanium implant for arthrodesis in the management of large osseous defects in the ankle

BACKGROUND

Large osseous defects (LOD) in the ankle occur because of multiple aetiologies. Advancement in 3-dimensional (3D) printing technologies has led to the use of custom implants and instrumentation their management. A 3D printed patient-specific porous titanium cage which allows for peripheral osteo-integration and autogenous bone-grafting could be an ideal implant in these cases.

METHODS

Retrospective review of a multi-centre, multi-surgeon consecutive cohort of patients requiring either TTC or AA for a large osseous defect between June 2019 - August 2020. A custom titanium prosthesis was 3D-printed according to CT measurements for implantation.

RESULTS

Mean follow up was 19.5 months (range 12-24 months). Plain radiographs and CT scans at 12 months confirmed osseointegration (stability) in 11of 13 patients (84%). Two patients developed late infection, one requiring revision surgery.

CONCLUSIONS

3D-Printed titanium implants in the management of LODs in the ankle offer a comparable success rate to other reported procedures, with unlimited geometric possibilities in the design allowing for accurate length correction. Their structural stability may offer an advantage over conventional bone graft techniques and limits the amount of bone-graft required.

LEVELS OF EVIDENCE

LOE III.

Effect of intramedullary nail stiffness on load-sharing in tibiotalocalcaneal arthrodesis: A patient-specific finite element study

Tibiotalocalcaneal (TTC) arthrodesis is a procedure to treat severe ankle and subtalar arthropathy by providing pain free and stable fusion using IM nails. These nails can be manufactured with multiple materials and some feature the ability to dynamize the arthrodesis construct. However, the impact of IM nail material and nail dynamization on load-sharing and in the setting of bone resorption have not been quantified. This work utilized a patient-specific finite element analysis model of TTC arthrodesis to investigate IM nails with differing material moduli and the impact of nail dynamization on load-sharing and intersegmental compression in the setting of bone resorption. Each nail was virtually inserted into a patient-specific model of a hindfoot, which was segmented into the three bones of the TTC complex and assigned material properties based on the densitometry of the bone. Compression, amount of load-sharing, and stress distributions after simulated bone resorption were quantified and compared between the varying IM nails. Simulations revealed that bone segments were only subjected to 17% and 22% of dynamic gait forces in the titanium and carbon fiber nail constructs, whereas the pseudoelastic NiTi nail constructs allowed for 67% of the same. The titanium and carbon fiber nails lost all initial compression in less than 0.13mm of bone resorption, whereas the NiTi nail maintained compression through all simulated values of bone resorption. These data highlight the poor load-sharing of static nail TTC arthrodesis constructs and the ability of a pseudoelastic IM nail construct to maintain intersegmental compression when challenged with bone resorption.

The Ankle Joint: Management of Significant Bone Loss with Arthrodesis

Segmental bone loss of the distal tibia and/or talus presents a challenge to successful reconstruction for the foot and ankle surgeon. When conservative care has been exhausted, multiple surgical treatment options are available including bone transport, bulk allografts, bulk autografts, titanium cages, and external fixation techniques. The primary goals of surgical correction include restoration of limb length as well as a plantigrade, stable lower extremity.

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.

Medial Femoral Condyle Free Flap for Persistent Osseous Nonunion of the First Metatarsophalangeal Joint: A Preliminary Report of a New Surgical Indication for the Medial Femoral Condyle Free Flap

Background

Recalcitrant or persistent nonunions of the metatarsophalangeal (MTP) joint occur following failed MTP surgery for MTP fusion, failed MTP prosthesis, for hallux rigidus or due to infection and erosion. A deficient soft tissue envelope and compromised vascular supply of tissues in this region compound further attempts to salvage the great toe and preserve function. The medial femoral condyle (MFC) free flap provides vascularized corticocancellous bone and periosteum and has been successfully used for a variety of complex hindfoot and ankle pathologies. We present an additional indication with a small cohort study demonstrating its use in persistent nonunions of the first MTP joint.

Methods

A retrospective review was completed of all MFC flaps used for revision of failed first MTP joint fusion from January 2019 to November 2022. Demographic information, comorbidities, as well as clinical and radiologic follow-up was obtained from the patient charts.

Results

Three patients were included with MTP nonunion and an average of 7.5 (range, 5-11) failed prior surgeries. Mean age at index surgery was 50 (range, 46-57) years. An osseous union was achieved in all patients after 82 (range, 75-88) days. Hardware removal was possible after 81 (range, 55-98) days. Mean follow-up was 17 (range, 5-31) months. We note a 100% flap success rate without returns to the operating room. The lengths of the bone flaps were 2 to 4 cm, the volumes were 8 to 12 cm3. Fixation was performed with 1 intramedullary K-wire. The recipient vessel in all patients was the dorsalis pedis artery or a tributary thereof. All arterial anastomoses were performed under the operating microscope.

Conclusion

The MFC free flap is a reasonable option for salvage of complex recalcitrant or persistent nonunions of the first MTP joint. More prospective long-term studies with functional outcomes are necessary to confirm these findings.

Level of Evidence

Level IV, retrospective case series.

Septic History Limits the Outcome of Tibiotalocalcaneal Arthrodesis

Joint destruction necessitates tibiotalocalcaneal arthrodesis (TTCA) in cases of clinical deficits that cannot be controlled conservatively, possibly leading to sepsis. We aimed to compare the underlying etiology of posttraumatic joint destruction and the outcomes after TTCA in patients with a septic or aseptic history. Between 2010 and 2022, 216 patients with TTCA were retrospectively enrolled (septic TTCA (S-TTCA) = 129; aseptic TTCA (A-TTCA) = 87). Patient demographics, etiology, Olerud and Molander Ankle Scores (OMASs), Foot Function Index (FFI-D) scores, and Short Form-12 Questionnaire (SF-12) scores were recorded. The mean follow-up period was 6.5 years. Tibial plafond and ankle fractures were the most common causes of sepsis. The mean OMAS was 43.0; the mean FFI-D was 76.7; and the mean SF-12 physical component summary score was 35.5. All the scores differed significantly between the groups (p < 0.001). With an average of 11 operations until the arthrodesis was achieved, the S-TTCA patients underwent about three times as many operations as the A-TTCA patients (p < 0.001), and 41% of S-TTCA patients remained permanently unable to work (p < 0.001). The significantly worse results of S-TTCA compared to A-TTCA show the long and stressful ordeal that patients with a septic history suffer. Further attention must be paid to infection prophylaxis and, if necessary, early infection revision.

Functional outcomes of tibiotalocalcaneal arthrodesis using a hindfoot arthrodesis nail in treating Charcot's arthropathy deformity

Background

Tibiotalocalcaneal arthrodesis or hindfoot fusion is a salvage surgical option used to treat symptomatic or severe deformity as a result of Charcot's arthropathy. It is an internal fixation that utilizes nails to stabilize the hindfoot after surgical correction of the deformity. This study intends to measure the change in functional outcomes of patients with Charcot's arthropathy using this technique and the time taken to achieve fusion.

Method

This study presents a series of 40 cases of Charcot's arthropathy where hindfoot fusion was done using a hindfoot arthrodesis nail. A retrospective analysis was done where these patients' functional scores had been evaluated preoperatively and postoperatively (serially) with the Short-Form Health Survey 36 (SF-36), American Orthopedic Foot and Ankle Society (AOFAS), Foot and Ankle Outcome Score (FAOS), and Foot Function Index (FFI). Along with its complication, the length of time required for the fusion is also reported.

Results

This study consists of 40 patients (13 men, 27 women; mean age 60.5 years; age range 52-68 years) with a mean follow-up of 64 months (range 24-108 months). The mean time taken for fusion was 5.1 months. All patients showed improvement in functional scoring (SF-36, AOFAS, FFI, and FAOS) postoperatively. We establish that the improvements were gradual over 2 years. Approximately 37.5% of patients had a minor complication and 2.5% had a major complication.

Conclusion

Hindfoot fusion using a hindfoot arthrodesis nail results in improved functional outcome with an acceptable fusion time and acceptable complication rate.

Level of evidence

Level III.

Tibiotalocalcaneal Arthrodesis in Severe Hindfoot Deformities

Tibiotalocalcaneal arthrodesis (TTCA) is the most common and reliable procedure in the treatment of patients with end-stage ankle arthritis combined with severe deformity. Many of these patients present with difficult previous sequelae that include nonunion, malunion, broken implants, vascular deficiencies, skin problems, or a combination of the previous. In that complex scenario, sometimes the only alternative treatment is a below-the-knee amputation. Image studies--weightbearing X-rays, tomography, and magnetic resonance - are fundamental to evaluate alignment and bone stock. When all conservative treatments fail to alleviate pain and dysfunction, the combination of osteotomies and arthrodesis is the procedure of choice. Surgical planning needs to be very detailed and thorough with a special focus on bone loss after debridement of non-healthy tissue and removal of metalwork. TTCA with grafting allows for the preservation of the limb in more than 80% of cases but at the expense of many complications with nonunion rates of approximately 20% of cases. There is controversy about the use of a retrograde nail versus specific TTCA plate and screws but results from biomechanical studies do not show a clear superiority of one specific construct. Amputation rates are close to 5% of cases after repeated failed surgeries. Bulk allografts increase the rate of nonunions but apparently do not have an influence on postoperative infections. Valgus positioning of the ankle/hindfoot is paramount to allow for maximal sagittal plane compensation from the midtarsal joints. Most patients are satisfied with the results of these salvage operations. The studies presented in this article have a considerable wide array of different scenarios that obviously bias some of the results, complications, and outcomes but together they present a persuasive pattern toward considering TTC with grafting and nail or plate fixation as a good salvage procedure that may help the patients to maintain their foot and ankle with a better alignment, function, and pain relief.

Arthrodesis in the Deformed Charcot Foot

Charcot neuroarthropathy (CN) is a systemic disease that causes fractures, dislocations, and deformities involving the foot and ankle, resulting in substantial risk of ulceration, infection, and function loss. Early recognition and prevention of collapsing foot and ankle are still the best options for the management of patients with diabetic CN. For a successful arthrodesis procedure, the principles of adequate joint preparation, deformity correction, and soft tissue protection and care are essentials, associated with robust fixation (internal and/or external), use of different biological graft options in segmental losses, and prolonged off-loading.

Improved Pain and Function After TTC Fusion With a Custom Cage

BACKGROUND

Three-dimensional custom cages can be used to treat complex ankle and hindfoot pathology and bone loss with potentially better patient satisfaction and higher fusion rates than tibiotalocalcaneal (TTC) fusion alone or in combination with bulk femoral head allograft. Yet there is limited literature to support this procedure. The purpose of this study is to objectively quantify the clinical and radiologic outcomes of patients undergoing patient-specific 3D-printed custom cage implantation to fill large defects around the ankle joint region as part of a limb-salvaging TTC fusion.

METHODS

This is a retrospective review of 21 patients (mean age 59.3 years) who underwent custom cage implantation with a TTC retrograde fusion nail by a single surgeon for massive bone loss of the ankle and hindfoot. Patient charts were reviewed for pain and functional outcomes, complications, and various demographics, including number of previous surgeries to the ipsilateral ankle. Mean follow-up was 32 months. All 21 patients had preoperative and postoperative pain and function scores available for analysis.

RESULTS

A total of 20 (95.2%) of the 21 patients had their cage in situ at final follow-up. Overall, with the numbers available, visual analog scale (VAS) for pain, Foot and Ankle Ability Measure (FAAM) activities of daily living subscale, and the 12-Item Short Form Health Survey (SF-12) mental and physical health scores significantly improved from preoperative to final follow-up. However, when compared to the overall US population of age-matched 55- to 64-year-old individuals, patients still remained relatively disabled. There were 2 failures, one of which required amputation and the other was treated nonoperatively with bracing.

CONCLUSION

In conclusion, in this relatively small, single-surgeon series, we found that 3D-printed custom cage technology offered a viable option for complex TTC fusion procedures performed in the presence of significant bone loss, with good fusion rates, however relatively modest improvement in functional outcomes.

LEVEL OF EVIDENCE

Level IV, retrospective case series.

Early Outcomes of Combined Total Ankle Total Talus Replacement Using a 3D-Printed Talus Component With Hindfoot Arthrodesis

Late-stage talar avascular necrosis (AVN) results in devascularization of the talus with osteonecrosis and subchondral collapse. A combined total ankle and total talus replacement (TATTR) with hindfoot arthrodesis may be utilized for end-stage talar AVN with tibiotalar and hindfoot joint arthritis. The purpose of this study is to evaluate the short-term outcomes of combined TATTR with hindfoot arthrodesis. Patients who underwent a combined TATTR or TTR with a hindfoot arthrodesis (subtalar with or without talonavicular arthrodesis) from 2016 to 2020 were retrospectively reviewed. Patient demographics, comorbidities, and surgical data were collected. Outcomes included the Visual Analog Scale (VAS) scores, range of motion, radiographic parameters, union rates, and complications. A total of 18 patients were reviewed. Nine patients were included with an average of 19.4 months follow-up. Significant postoperative improvements were observed in VAS scores (P < .001), ankle plantarflexion (P = .04), talocalcaneal height (P = .03), and tibiotalar alignment (P = .02). All patients achieved a successful union of their subtalar and talonavicular joints arthrodesis. There was one reoperation for a persistent varus ankle deformity. This is the first study to evaluate the clinical outcomes, radiographic outcomes, and union rate in combined TATTR with hindfoot arthrodesis. The early results demonstrated significant clinical improvement with 100% hindfoot union rate and no prosthetic failure.Level of Evidence: IV.

Lower Limb Salvage Using Patent-Specific 3D-Printed Titanium Cage Following Severe Left Ankle Traumatic Partial Amputation: A Pediatric Case Report

BACKGROUND

Patients with large bony defects of the ankle who wish to avoid amputation have limited surgical intervention options for limb salvage. Each of these interventions are technically complex and present significant risk for complications. The use of a patient-specific 3D-printed titanium cage in conjunction with a tibiotalocalcaneal (TTC) arthrodesis using a retrograde nail is another management option. This case adds to the scarce published literature on this technique.

CASE PRESENTATION

This report presents the case of a 16-year-old female who suffered a traumatic partial amputation of her left distal lower extremity following an all-terrain-vehicle accident that resulted in a 10.0 × 10.0 cm skin laceration and a 5-cm subsegmental bony loss of the distal tibia. She was successfully treated using a patient-specific 3D-printed titanium truss cage in conjunction with a TTC arthrodesis using a retrograde nail.

CONCLUSIONS

The decision to amputate or attempt limb salvage in a severely injured lower limb is still a topic of active debate. However, literature has shown that patients who undergo limb salvage surgery have better psychological health outcomes and equivalent functional outcomes as patients who have undergone amputation. Therefore, research on techniques that optimize and advance limb salvage surgery is needed. As the numerous potential benefits and limitations of patient-specific 3D-printed implants are assessed throughout the field of orthopedics, further research and cost-analysis will be required. Cases such as the one presented add to the limited existing literature of patient-specific 3D-printed implant for treatment of large distal lower extremity bony defects.

LEVELS OF EVIDENCE

Level V (Case Report).

Tibiotalocalcaneal Arthrodesis with Structural Allograft for Management of Large Osseous Defects of the Hindfoot and Ankle: A Systematic Review and Meta-Analysis

Large osseous defects of the hindfoot and ankle pose a surgical challenge. Tibiotalocalcaneal (TTC) arthrodesis utilizing a structural allograft may be required to fill the osseous void, preserve limb length and achieve fusion. Several authors have reported small case series on this topic, however outcomes have varied and no systematic review of this data has been published to date. The primary aim of this study is to report rates of osseous union, limb salvage and complications in patients undergoing TTC arthrodesis with a structural allograft. A total of 11 publications were identified that met the inclusion criteria. One hundred seventy-five patients were included with a weighted mean age of 60.5 (range 50-72) years and follow-up period of 29.7 (range 3-62) months. Femoral head allograft was the most commonly utilized structural graft and a retrograde intramedullary nail was the most common fixation construct. Results demonstrated an overall union rate of 67.4%, limb salvage rate of 92.5% and complication rate of 26.6%. Allograft-related complications were rare with an allograft fracture rate of 0.1% and allograft collapse rate of 1.2%. There was no significant difference in union rate when using a retrograde intramedullary nail versus a plate construct (p = .9148). TTC arthrodesis with use of a structural allograft is a viable treatment option for limb salvage when faced with complex hindfoot and ankle pathology involving large osseous defects. Despite high rates of radiographic nonunion, this approach can provide patients with a stable and functional limb while avoiding amputation.

Ankle and Tibiotalocalcaneal Fusion

Arthrodesis of the ankle and/or tibiotalocalcaneal joints is a reliable treatment of arthritic conditions of the ankle and hindfoot. It may be complicated by infection, nonunion, malunion, fracture, wound complications, nerve injury, and adjacent joint degeneration. These complications may be addressed with a variety of techniques but should be done so carefully so as not to lead to more complex problems. A thorough work-up and discussion should take place prior to any surgical intervention and treatment. Several cases are presented to illustrate revision arthrodesis techniques and the management of these complications.

Outcomes of Surgical Reconstruction Using Custom 3D-Printed Porous Titanium Implants for Critical-Sized Bone Defects of the Foot and Ankle

BACKGROUND

Treating critically sized defects (CSDs) of bone remains a significant challenge in foot and ankle surgery. Custom 3D-printed implants are being offered to a small but growing subset of patients as a salvage procedure in lieu of traditional alternates such as structural allografts after the patient has failed prior procedures. The long-term outcomes of 3D-printed implants are still unknown and understudied because of the limited number of cases and short follow-up durations. The purpose of this study was to evaluate the outcomes of patients who received custom 3D-printed implants to treat CSDs of the foot and ankle in an attempt to aid surgeons in selecting appropriate surgical candidates.

METHODS

This was a retrospective study to assess surgical outcomes of patients who underwent implantation of a custom 3D-printed implant made with medical-grade titanium alloy powder (Ti-6Al-4V) to treat CSDs of the foot and ankle between June 1, 2014, and September 30, 2019. All patients had failed previous nonoperative or operative management before proceeding with treatment with a custom 3D-printed implant. Univariate and multivariate odds ratios (ORs) of a secondary surgery and implant removal were calculated for perioperative variables.

RESULTS

There were 39 cases of patients who received a custom 3D-printed implant with at least 1 year of follow-up. The mean follow-up time was 27.0 (12-74) months. Thirteen of 39 cases (33.3%) required a secondary surgery and 10 of 39 (25.6%) required removal of the implant because of septic nonunion (6/10) or aseptic nonunion (4/10). The mean time to secondary surgery was 10 months (1-22). Multivariate logistic regression revealed that patients with neuropathy were more likely to require a secondary surgery with an OR of 5.76 (P = .03).

CONCLUSION

This study demonstrated that 74% of patients who received a custom 3D-printed implant for CSDs did not require as subsequent surgery (minimum of 1-year follow-up). Neuropathy was significantly associated with the need for a secondary surgery. This is the largest series to date demonstrating the efficacy of 3D-printed custom titanium implants. As the number of cases using patient-specific 3D-printed titanium implant increases, larger cohorts of patients should be studied to identify other high-risk groups and possible interventions to improve surgical outcomes.

LEVEL OF EVIDENCE

Level IV, case series.

The Long-Term Clinical Results of Total Talar Replacement at 10 Years or More After Surgery

BACKGROUND

Total talar replacement has been reported to have favorable short-term and intermediate-term results for the treatment of osteonecrosis of the talus. The purpose of this study was to evaluate the long-term clinical results of total talar replacement for a minimum of 10 years after the surgical procedure.

METHODS

From October 2005 to April 2011, 19 ankles in 18 patients (1 male and 17 female) were treated using a total talar prosthesis for osteonecrosis of the talus. The median follow-up period was 152 months (interquartile range [IQR], 138, 160 months). The Ankle Osteoarthritis Scale (AOS) score, the Japanese Society for Surgery of the Foot (JSSF) Ankle-Hindfoot Scale score, and the presence of osteophytes and degenerative changes in the adjacent joints were assessed preoperatively and at the final follow-up. Subsidence of the prosthesis was also assessed at the earliest opportunity for full weight-bearing and the final follow-up. The postoperative range of motion of the ankle was assessed at the final follow-up.

RESULTS

The median scores for all subscales of the AOS significantly improved. The median JSSF Ankle-Hindfoot Scale score significantly improved from 58 (IQR, 55, 59.5) to 97 (IQR, 87, 99.5). In the subcategories of this scale, the median pain score improved from 20 (IQR, 20, 20) to 40 (IQR, 30, 40), and the median function score improved from 28 (IQR, 26, 30.5) to 47 (IQR, 47, 50). The median postoperative range of motion of the ankle was 45° (IQR, 42.5°, 55°). Subsidence of the implant was not recognized at the final follow-up (p = 0.083). Proliferation of osteophytes and degenerative changes in the adjacent joints did not affect the overall results.

CONCLUSIONS

The customized alumina ceramic total talar prosthesis produced stable clinical outcomes over 10 years, and the patients treated with total talar replacement showed favorable clinical results over this time frame.

LEVEL OF EVIDENCE

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

Early results and complication rate of the LapiCotton procedure in the treatment of medial longitudinal arch collapse: a prospective cohort study

INTRODUCTION

Instability/collapse of the medial column has been associated with many conditions, particularly progressive collapsing foot deformity (PCFD), hallux valgus (HV), and midfoot arthritis (MA). Restoration of first ray length and sagittal plane alignment to restore the foot tripod is essential when treating these deformities. This study aimed to assess early results, healing, and complication rate of a distraction dorsal opening plantarflexion wedge allograft first tarsometatarsal joint fusion (LapiCotton Procedure) in patients with collapse/instability of the medial column.

METHODS

In this prospective cohort study, we included PCFD, HV, and MA patients that underwent a LapiCotton procedure. Fusion site healing was defined by > 50% bone bridging in both interfaces between allograft wedge and host bone using weight-bearing computed tomography (WBCT) after 3 months. First ray collapse radiographic correction and minor and major complications (deep dehiscence, deep infection, and reoperation) were assessed.

RESULTS

A total of 22 patients (22 feet) were included (11 PCFD, 6 MA, and 5 of HV patients). Mean follow-up was 5.9 months (range 3-12) and median allograft size was 8 mm (range 5-19 mm). Bone healing was observed in 91% of cases. Two minor complications (9%, both superficial dehiscence) and one major complication (4.5%, deep infection) were observed. Statistically significant improvement of the sagittal plane talus-first metatarsal angle was observed, with mean improvement of 9.4° (95% CI 6.7-12.1°; p < 0.0001).

CONCLUSION

In this prospective cohort study of 22 patients treated with the LapiCotton procedure for medial longitudinal arch collapse/instability, we observed a low complication rate (9% minor, 4.5% major), high healing rate after 3 months (91%), one clinically stable radiographic non-union (4.5%) and one unstable non-union (4.5%) needing reoperation. Our results demonstrate promising initial results for LapiCotton technique in treating collapse of the medial longitudinal arch in patients with PCFD, MA and HV deformities. Long-term results are needed to confirm these promising results.

LEVEL OF EVIDENCE

Level II, prospective cohort study.

Biologic Augmentation of Tibiotalocalcaneal Arthrodesis With Allogeneic Bone Block Is Associated With High Rates of Fusion

BACKGROUND

The orthopaedic conditions and systemic comorbidities that occur in patients who require bone block tibiotalocalcaneal (TTC) arthrodesis have made this procedure associated with a higher-than-normal risk of nonunion, graft collapse, hardware failure, and amputation. Here, we present a novel approach to bone block TTC arthrodesis using adjunctive osteoinductive agents and a prolonged course of protected weightbearing to assess if we could improve on historical outcomes. We also evaluated the efficacy of a vascularized medial femoral condyle (MFC) free flap to augment TTC arthrodesis.

METHODS

Fourteen adult patients underwent bone block TTC arthrodesis biologically augmented with fresh-frozen femoral head allograft, bone marrow aspirate concentrate, and demineralized bone matrix cortical fibers. Three patients with soft tissue defects underwent vascularized reconstruction with an MFC free flap. Radiographic union, the Foot Function Index (FFI), and PROMIS pain interference (PI), and physical function (PF) scores were assessed at follow-up.

RESULTS

TTC fusion was documented on plain radiograph in 13 of 14 patients (92.9%) and CT in 10 of 11 patients (90.9%). Mean time to fusion was 183.2 ± 83.2 days. One patient (7.1%) experienced nonunion and persistent infection requiring amputation. Patients who underwent vascularized bone grafting had significantly shorter time to fusion (112.3 ± 31.7 days vs 204.4 ± 82.7 days, P = .05). Patient-reported outcomes revealed mild to moderate pain and dysfunction after 1 year (mean FFI = 41.0% ± 23.1%, PROMIS PI = 58.3 ± 1.8, PROMIS PF = 39.0 ± 2.2).

CONCLUSION

In this relatively small series, the biologic augmentation of bone block TTC arthrodesis with osteoinductive agents and protective weightbearing resulted in excellent rates of fusion, modest pain, and preserved function of the lower extremity in almost all those treated. Osseous healing appears to be enhanced and accelerated with application of an MFC flap. We believe that this approach offers a viable salvage option for these challenging clinical problems.

LEVEL OF EVIDENCE

Level IV, case series.

Treatment of Severe Avascular Necrosis of the Talus Using a Novel Keystone-Shaped 3D-Printed Titanium Truss Implant

Background

Avascular necrosis (AVN) of the talus most commonly occurs secondary to trauma. Significant bone loss and collapse in severe talar AVN remains an operative challenge. Tibiotalocalcaneal arthrodesis (TTC) using femoral head allograft is at risk of collapse and subsidence. The use of a void-filling titanium truss can mitigate against this. This study describes the use of a novel keystone shaped 3D-printed titanium truss for treatment of severe talar AVN.

Methods

Three patients with end-stage AVN of the talus were included. Each patient underwent a TTC arthrodesis with a custom-made, 3D-printed, keystone-shaped, truss implant in conjunction with a hindfoot intramedullary nail. Modified patient American Orthopaedic Foot & Ankle Society (AOFAS) scores were recorded at the preoperative, 6-month, 12-month, and annual postoperative timepoints.

Results

All patients progressed to satisfactory radiological union by one year. Mean follow up time was 32 months (24-48 months). Mean preoperative modified AOFAS score was 5. There was progressive improvement in AOFAS scores from 6 months postoperatively. Mean modified AOFAS score improved from 28 at 6 months to 37 at 2 years postoperatively.

Conclusion

Custom-made 3D-printed titanium trusses provide promising outcomes for treating severe AVN of the talus. The "keystone" design is advantageous as it allows for bone stock preservation and conforms to the shape of the native calcaneum. All patients showed progressive improvements in outcomes at sequential time intervals postoperatively. The implant provides a strong mechanical structure resisting collapse and subsidence during the arthrodesis process.

Level of Evidence

Level IV, retrospective case series.

Avascular Osteonecrosis of the Talus: Current Treatment Strategies

Avascular osteonecrosis (AVN) of the talus (AVNT) is a painful and challenging clinical diagnosis. AVNT has multiple known risk factors and etiologies and presents at different stages in severity. Given these unique factors, the optimal treatment solution has yet to be determined. Both joint-preserving and joint-sacrificing procedures are available, including core decompression and arthrodeses. Recently, new salvage and replacement techniques have been described including vascularized pedicle bone grafts and total talus replacement using patient-specific prosthesis; however, evidence remains limited. This review examines the current trends AVNT treatment and the emerging data behind these novel techniques.

[Salvage options following failed total ankle arthroplasty]

The number of patients with osteoarthritis of the ankle, which are treated by arthroplasty, has continuously increased in recent years. The survival time of these implants is far below the results following hip and knee arthroplasty. In some cases a failure rate of approximately 1% per year or a survival rate of 70% after 10 years has been reported. The most frequent reasons for revision of an ankle prosthesis are aseptic loosening, technical implantation errors and persisting pain. For the revision of an ankle prosthesis there are basically two treatment options. For a long time, ankle arthrodesis was considered the gold standard after a failed prosthesis. In recent years, there has been an increasing trend towards re-implantation of an ankle prosthesis, as this preserves the functionality and mobility of the ankle joint as far as possible. Depending on the reason for failure and the size of the bony defect, a decision must be made regarding a one-stage and a two-stage procedure with bone augmentation. This article presents the advantages and disadvantages of arthrodesis and revision arthroplasty after failed primary ankle arthroplasty and highlights the special features of surgery.

Risk factors for nonunion following tibiotalocalcaneal arthrodesis: A systematic review and meta-analysis

BACKGROUND

The goal of this study is to review the literature to identify risk factors for nonunion after tibiotalocalcaneal arthrodesis (TTCA) and stratify them based on strength of evidence.

METHODS

Five databases were searched from inception to May 17th, 2020. Abstracts and full-text articles were screened for those that included risk factors predictive of nonunion following TTCA.

RESULTS

Eight studies involving 624 patients were included and 33 potential risk factors for nonunion were identified. Strong evidence supported prior peripheral neuropathic conditions as risk factors for nonunion following surgery (OR: 2.86, 95% CI: 1.56-5.23).

CONCLUSION

TTCA is an effective salvage procedure but is associated with high nonunion rates. The results of our meta-analysis suggest that prior peripheral neuropathic conditions have strong evidence for failure to achieve union. Surgeons should be cognizant of these risks when performing TTCA and carefully monitor patients with the aforementioned comorbidity to achieve successful results.

Ankle Height Preservation with the Hind Foot Nail and Iliac Crest Bone Blocks in Patients with Sequelae of Partial or Complete Talus Bone Loss

Introduction:

The management of talus bone loss in trauma is difficult and unsatisfactory. This study assessed whether the height of the ankle was preserved when entire or partial talar bone loss was managed with hind foot intramedullary nail augmented with autogenous rectangular or trapezoidal cortico-cancellous bone blocks from the iliac crest in the presence of active or latent infection.

Materials and methods:

Four patients were included in the study from January 2011 to December 2017. In the first stage, all four patients underwent debridement of the ankle, total or partial excision of the talus, and antibiotic-loaded bone cement spacer (ALBC) placement in the ankle joint. The second stage of the arthrodesis procedure was initiated six to eight weeks after the primary procedure, where these patients underwent arthrodesis with hindfoot nail and bone blocks from the iliac crest.

Results:

All patients were followed-up for an average of 17.6 months (range 12.0 – 32.0 months). The arthrodesis site had united in all these four patients. The AOFAS scores were satisfactory in all patients. One patient underwent nail removal after the arthrodesis site had united.

Conclusions:

The hind foot nail with iliac crest bone block maintains the ankle height and ensures successful arthrodesis. In patients with partial/ complete bone loss with suspicion or confirmation of infection, staging the arthrodesis procedure minimises the chance of complications.

The King's Sliding Hindfoot Osteotomy for the Treatment of Talus Body Defects-Results of a New Technique in Tibiotalocalcaneal Arthrodesis

Bone loss after avascular necrosis of the talus secondary to acute traumatic or chronic pathologies often requires surgical reconstruction. This study reports the early results of a sliding oblique hindfoot osteotomy for salvage procedures combined with tibiotalar arthrodesis to achieve a well-aligned, painless, plantigrade foot. All patients presenting to our institution with severe talus body defects requiring corrective surgery between January 2016 and August 2020 were included. An oblique osteotomy of the diseased talus was performed to correct anterior talus subluxation and prevent excessive loss of height at the tibiotalar apposition and to correct varus-valgus deformity. A retrograde hindfoot nail was used for intramedullary tibiotalocalcaneal arthrodesis. Patients were prospectively followed. Primary outcomes included assessment of mobility and union at 6 months. Secondary outcomes included 30-day postoperative complications, patient satisfaction and change in American Orthopaedic Foot & Ankle Society (AOFAS) score at 1-year postoperation. Nine patients underwent this procedure with a mean follow-up of 18 months (4-36 months). Average age was 66 (58-81) years. Mean body mass index was 33.7 (22-38) kg/m². All patients went on to fusion and were ambulating at 6 months (n = 8). At 1 year, the mean improvement in AOFAS was 28.9 points (p < .05) (n = 7) and all patients were satisfied with the outcome of their treatment. This technique represents an alternative to conventional hindfoot salvage techniques showing predictable outcomes in complex hindfoot deformity with talar body collapse and anterior subluxation. Further quantitative studies are needed to define if this technique minimizes limb shortening/limb-length discrepancies when compared to traditional horizontal cuts.

High-strength, porous additively manufactured implants with optimized mechanical osseointegration

Optimization of porous titanium alloy scaffolds designed for orthopedic implants requires balancing mechanical properties and osseointegrative performance. The tradeoff between scaffold porosity and the stiffness/strength must be optimized towards the goal to improve long term load sharing while simultaneously promoting osseointegration. Osseointegration into porous titanium implants covering a wide range of porosity (0%-90%) and manufactured by laser powder bed fusion (LPBF) was evaluated with an established ovine cortical and cancellous defect model. Direct apposition and remodeling of woven bone was observed at the implant surface, as well as bone formation within the interstices of the pores. A linear relationship was observed between the porosity and benchtop mechanical properties of the scaffolds, while a non-linear relationship was observed between porosity and the ex vivo cortical bone-implant interfacial shear strength. Our study supports the hypothesis of porosity dependent performance tradeoffs, and establishes generalized relationships between porosity and performance for design of topological optimized implants for osseointegration. These results are widely applicable for orthopedic implant design for arthroplasty components, arthrodesis devices such as spinal interbody fusion implants, and patient matched implants for treatment of large bone defects.

Outcome of Pantalar Fusion With Femoral Head Allograft in Avascular Necrosis of Talus

Background: Avascular necrosis (AVN) of the talus is a challenging condition that is caused primarily by trauma. The severity of the talus fracture determines the risk of AVN. Severe osteonecrosis with the loss of talar integrity can be treated with arthrodesis and structural bone graft.

Method: This study shows the experience of pantalar arthrodesis using hindfoot arthrodesis nail, screw fixation, and femoral head allograft in four patients.

Result: All patients were satisfied in terms of pain and function after an average of 4 months postsurgery. Limb length discrepancy was <1 cm and hindfoot fusion was achieved by 3 months. The mean score for SF-36 physical function and AOFAS hindfoot score at a 2-year postpantalar arthrodesis was 88 and 80.8, respectively.

Conclusion: Hindfoot ankle arthrodesis, with the usage of femoral head allograft, can be successfully used for the treatment of traumatic AVN of talus.

Three-Dimensional Printed Cage in Patients With Tibiotalocalcaneal Arthrodesis Using a Retrograde Intramedullary Nail: Early Outcomes

Introduction. Segmental bone loss in the hindfoot hinders the chance of successful outcomes. Tibiotalocalcaneal arthrodesis is a reliable option; nevertheless, the risk of nonunion is high. Three-dimensional (3D) printed titanium implants offer a strong scaffold that can be customized and has demonstrated encouraging healing rates. In this study, we described the clinical outcomes and the radiologic union rate of a case series of patients with hindfoot arthrodesis, using a retrograde intramedullary nail associated to a 3D printed titanium cage. Methods. Seven patients undergoing hindfoot arthrodesis, using a retrograde intramedullary nail associated to a custom 3D printed titanium cage, were included. Demographic data were collected. Functional outcomes were assessed using the American Orthopedic Foot and Ankle Score and the Visual Analogue Scale for pain. Hindfoot alignment and radiographic union were evaluated using weight-bearing radiographs and computed tomography scan, respectively. Results. A total of 6 (85%) patients had more than 50% bony bridging. Only 1 patient underwent below knee amputation due to recurrence of chronic osteomyelitis. Two additional patients had minor complications. Conclusion. Tibiotalocalcaneal arthrodesis using customized titanium cages for patients with large bone defects has shown a high rate of union in those at risk of nonunion. However, further research with larger series is needed.Levels of Evidence: Level IV: Case series.

Use of Three-dimensional Titanium Trusses for Arthrodesis Procedures in Foot and Ankle Surgery: A Retrospective Case Series

Periarticular osseous defects pose a challenge when considering arthrodesis. Failure to restore the cubic content of bone can result in shortening and malalignment, as well as subsequent biomechanical issues. This study reports on 12 patients treated with patient-specific 3-D printed (7) and prefabricated titanium trusses (5). Twelve consecutive patients were treated for osseous defects of the forefoot, hindfoot, and ankle with patient-specific, 3D printed or prefabricated manufacturer titanium trusses. Seven were customized, patient-specific 3D printed trusses (4WEB, Frisco, Texas) and 5 were prefabricated manufacturer titanium trusses. All patients had a minimum of 6 months of clinical and radiographic follow-up. and no patients were lost to follow-up. Seven of the 12 patients had a computed tomography (CT) scan performed following surgery. Successful limb or ray salvage was achieved in 11 of 12 patients (91.7%). Six of 7 patients (85.7%) with a postoperative CT scan, went on to complete radiographic consolidation across all arthrodesis sites. The remaining 5 patients showed complete consolidation across the arthrodesis sites on plain film radiographs. Complications included one patient with a residual midfoot deformity that required a subsequent midfoot osteotomy in order to obtain a plantigrade foot following successful tibiotalocalcaneal (TTC) arthrodesis, and a below knee amputation in one patient who underwent revision TTC arthrodesis to salvage avascular necrosis of the talus that developed following the index procedure. Eleven of 12 patients undergoing arthrodesis demonstrated successful union with both customized, patient-specific 3D printed and prefabricated manufacturer titanium trusses on CT scans or radiographs. The average follow-up was 14 months. Reports on traditional methods of addressing periarticular defects in patients requiring arthrodesis show mixed results and relatively high complication rates. Custom, 3D printed and prefabricated titanium truss technology offers an alternative to traditional methods for large, periarticular osseous defects.

Femoral Head Allografts for Talar Body Defects

BACKGROUND

Large structural bone deficits after a failed ankle arthroplasty or avascular necrosis (AVN) of the talus present a complex reconstruction challenge. The aim of this study was to report the results of patients undergoing an ankle arthrodesis or tibiotalocalcaneal fusion using a femoral head allograft (FHA).

METHODS

All ankle and tibiotalocalcaneal fusions using FHA between February 2006 and January 2019 were included. Forty-four patients (45 ankles) with a mean follow-up of 42.8 months were studied. Males accounted for 58.1% (25/43 patients). All patients had either failure of primary or revision total ankle arthroplasty (TAA) or AVN of the talus. Pre- and postoperative Veterans RAND Health Survey (VR-12), Foot and Ankle Ability Measure (FAAM), Ankle Osteoarthritis Scale (AOS) and visual analog scale (VAS) for pain scores were obtained. A patient satisfaction survey was distributed postoperatively and results were tabulated.

RESULTS

Preoperatively to postoperatively, the VR-12 Mental score remained essentially unchanged (P = .752) and the VR-12 Physical score improved (P = .007); the FAAM Activities of Daily Living (ADL) and Sport scores improved (P < .001); the AOS Pain and Disability scores improved (P < .001); and the man VAS score improved (P < .001). The overall satisfaction rate was 78.6 on a 100-point scale. At an average of 18.7 weeks, 90.7% of the ankles were substantially fused. Five patients went on to nonunions and revision surgery.

CONCLUSION

The use of FHA to treat talar defects was a viable option. In this complex patient population, the arthrodesis rate was high at 89% with very positive patient-reported outcome scores.

LEVEL OF EVIDENCE

Level IV, case series.

Comparison of 3D Printed Spherical Implants versus Femoral Head Allografts for Tibiotalocalcaneal Arthrodesis

Successful tibiotalocalcaneal (TTC) arthrodesis can be difficult to achieve in patients with bulk bone defects even with the use of femoral head allograft. Retrograde intramedullary nail placement through custom 3-dimensional (3D) spherical implants is an innovative option for these patients. The purpose of this study was to compare fusion rates, graft resorption, and complication rates between patients undergoing TTC fusion with 3D sphere implants versus femoral head allografts. Patients who underwent TTC arthrodesis with an intramedullary nail along with a 3D spherical implant (n = 8) or femoral head allograft (n = 7) were included in this study. The rate of successful fusion of the tibia, calcaneus, and talar neck to the 3D sphere or femoral head allograft was compared between the groups. The rate of total fused articulations was significantly higher in the 3D sphere group (92%) than the femoral head allograft group (62%; p = .018). The number of patients achieving successful fusion of all 3 articulations was higher in the 3D sphere group (75%) than the femoral head allograft group (42.9%, p = .22). The rate of graft resorption was significantly higher in the femoral head allograft group (57.1%) than the 3D sphere group (0%, p = .016). There were no significant differences between the groups in terms of complications. These data demonstrate that the use of a custom 3D printed sphere implant is safe in patients with severe bone loss undergoing TTC arthrodesis with a retrograde intramedullary nail and may result in improved rates of successful arthrodesis.

Total Ankle Total Talus Replacement Using a 3D Printed Talus Component: A Case Report

The 3D custom total talus replacement is a novel treatment for avascular necrosis of the talus. However, patients who require a total talus replacement often have concomitant degenerative changes to the tibiotalar, subtalar, or talonavicular joints. The combined 3D custom total ankle-total talus replacement (TATTR) is used for patients with an unreconstructable talus and adjacent tibial plafond involvement. The goal of performing a TATTR is to provide pain relief, retain motion at the tibiotalar joint, maintain or improve the patient's functional status, and minimize limb shortening. TATTR is made possible by 3D printing. The advent of 3D printing has allowed for the accurate recreation of the native talar anatomy with a talar dome that can be matched to a total ankle replacement polyethylene bearing. In this article, we will discuss a case of talar avascular necrosis treated with a combined TATTR and review the current literature for TATTR.

Two-Staged Revision Total Ankle Arthroplasty Surgery with Primary Total Ankle Arthroplasty System: A Case Report

CASE

Case of a 2-staged revision surgical technique for the treatment of an aseptic total ankle arthroplasty (TAA) loosening: first surgery: removal of the loosened and painful TAA Scandinavian Total Ankle Replacement, with exclusion of infection, and reconstruction of the large bone defect (bone-defect downsizing surgery); proof of successful ankle bone reconstruction by CT-scan imaging; second surgery: implantation of a primary VANTAGE TAA (ankle reconstruction with new primary TAA).

CONCLUSION

The present case shows the management of a failed TAA with bone defect by performing a 2-step surgical approach: removal of loosened TAA with simultaneous bone stock restoration and then implantation of a new primary TAA. This concept is a possible alternative to a post-TAA ankle arthrodesis or to the use of a TAA revision system.

Three-dimensional Printing in Orthopaedic Surgery: Current Applications and Future Developments

Three-dimensional (3D) printing is an exciting form of manufacturing technology that has transformed the way we can treat various medical pathologies. Also known as additive manufacturing, 3D printing fuses materials together in a layer-by-layer fashion to construct a final 3D product. This technology allows flexibility in the design process and enables efficient production of both off-the-shelf and personalized medical products that accommodate patient needs better than traditional manufacturing processes. In the field of orthopaedic surgery, 3D printing implants and instrumentation can be used to address a variety of pathologies that would otherwise be challenging to manage with products made from traditional subtractive manufacturing. Furthermore, 3D bioprinting has significantly impacted bone and cartilage restoration procedures and has the potential to completely transform how we treat patients with debilitating musculoskeletal injuries. Although costs can be high, as technology advances, the economics of 3D printing will improve, especially as the benefits of this technology have clearly been demonstrated in both orthopaedic surgery and medicine as a whole. This review outlines the basics of 3D printing technology and its current applications in orthopaedic surgery and ends with a brief summary of 3D bioprinting and its potential future impact.

Treatment of Severe Ankle and Hindfoot Deformity: Technique Using Femoral Head Allograft for Tibiotalocalcaneal Fusion Using a Cup-and-Cone Reamer

Limb shortening due to structural bone loss in tibiotalocalcaneal arthrodesis is a concern that can negatively impact the patient's gait and weight-bearing. To aid in preventing the risk of limb shortening, the use of a femoral head allograft and intramedullary nail in tibiotalocalcaneal arthrodesis has been shown to successfully preserve limb length in patients with structural bone deficits. We present our technique using a femoral head allograft with a cup-and-cone reamer for the treatment of severe ankle and hindfoot deformity.

Avascular Necrosis of the Talus

Talar osteonecrosis results from trauma to the fragile blood supply to the talus. Many etiologies exist that can cause talar osteonecrosis, with the most common being talar neck fractures. Patients with talar osteonecrosis frequently present with progressive ankle pain and limited range of motion. Treatment strategy depends primarily on the stage of disease. Conservative care in the form of medications and bracing treatment can be beneficial for patients with low functional status and early disease stages. Surgical options also exist for early disease without talar collapse that can potentially preserve the tibiotalar joint. Once talar collapse develops, surgical treatment is move invasive and typically involves an arthrodesis or talus arthroplasty. Although some treatment guidelines exist based on the disease stage, talar osteonecrosis is a complex problem, and treatment strategy should always be determined on a case-by-case basis carefully examining all clinical aspects.

Three-dimension correction of Charcot ankle deformity with a titanium implant

BACKGROUND

Charcot neuroarthropathy of the ankle is an extremely challenging clinical dilemma, and its surgical management can be highly complicated. The goal of Charcot ankle treatment is to to restore a plantigrade and stable foot, and thus to avoid ulceration with subsequent infection. This report aims to introduce a method of correcting ankle deformity using a novel 3D printing technique.

PATIENT AND METHODS

One patient with Charcot ankle deformity was operated in this study. The ankle deformity of this patient was quantified in three dimensions through computed tomography. On the basis of the computed tomography scans, a new titanium implant was designed and manufactured using 3D printing. The implant was applied in the surgery of tibio-talo-calcaneal arthrodesis to restore local anatomy of the affected ankle of the patient with Charcot neuroarthropathy.

RESULTS

Evaluation of the post-operative radiography indicated union in the affected ankle. After surgery, the planar foot in this patient was restored. The patient was satisfied with the post-operative course, and joint fusion was successful as indicated by 2-year post-operative evaluation. The results of post-operative follow-up showed that the lower limb length of the patient with Charcot neuroarthropathy was salvaged, and the patient retained the plantigrade foot.

CONCLUSION

Three-dimensional printing technique combined with tibio-talo-calcaneal arthrodesis may help to correct ankle deformity in patients with Charcot neuroarthropathy.

Management of Osseous Defects in the Tibia: Utilization of External Fixation, Distraction Osteogenesis, and Bone Transport

The use of external fixators for distraction osteogenesis has revolutionized treatment options for segmental bone defects in the tibia. Following corticotomy, the latency phase allows the biologic environment to initiate healing, and optimized distraction rates produce regenerate. Regenerate consolidation can be improved with local and systemic biologic optimization. Consolidation time is often considered to be 3 to 4 times longer than distraction in adults. Soft tissue considerations are important during external fixation and distraction. Additionally, slow regenerate can be benefited by various techniques discussed in this article. Distraction osteogenesis is a beneficial tool for segmental bone defects.

Retrospective review of complications following long tourniquet time in foot and ankle surgery

BACKGROUND

Tourniquet use is ubiquitous in orthopaedic surgery to create a bloodless field and to facilitate safe surgery, however, we know of the potential complications that can occur as a result of prolonged tourniquet time. Experimental and clinical research has helped define the safe time limits but there is not much literature specific to foot and ankle surgery.

METHODS

A retrospective review of the postoperative course of patients with prolonged tourniquet time (longer than 180 min) for foot and ankle procedures was done. Data related to the patient factors and the surgical procedure was collected. The length of stay, re-admissions and complications were the important indicators of the individual patient's recovery.

RESULTS

Twenty patients were identified with longer than 180-min tourniquet times for complex foot and ankle procedures. The average uninterrupted tourniquet time was 191 min. Eight of the twenty procedures were revision surgeries. The average length of stay was 3 days and there were no re-admissions within 30 days. Eight patients (40%) had at least one recorded complication. The complications seen in this group were transient sensory loss, wound issues, superficial infection, ongoing pain and non-union.

CONCLUSIONS

This case series has not revealed any major systemic complications resulting from the prolonged tourniquet such as pulmonary embolism or renal dysfunction. Unlike past literature on knee procedures with extended tourniquet times, no major nerve palsies were seen in our patient group. Our understanding of the local and systemic effects of tourniquet is not complete and this study demonstrates that the complications do not necessarily increase in a linear fashion in relation to the tourniquet time.

Tibiotalocalcaneal Arthrodesis Using a Novel Retrograde Intramedullary Nail

Background. Tibiotalocalcaneal (TTC) arthrodesis is a common treatment option for complex hindfoot pathology. Overall union rates range from 50% to 86% but can be even lower in certain populations. A novel retrograde intramedullary nail has recently been developed. The purpose of this study was to report fusion rates, time to weight-bearing, and complications with the use of the A3 Fusion Nail. Methods. All patients 18 years or older who underwent TTC arthrodesis with an A3 Fusion Nail at a single institution from 2010 to 2015 with a minimum 3-month follow-up were included in this study. Rates of successful fusion, time to union, time to weight-bearing, and complications were evaluated. A total of 20 patients with an average age of 58.1 years and an average follow-up of 12.5 months met inclusion criteria. Results. Successful TTC arthrodesis was achieved in 14 of 20 patients (70%) overall. Average time to union was 8.1 months, and average time to weight-bearing was 6.8 weeks. Of 20 patients, 17 (85%) required femoral head allograft for bulk bone defects, and the union rate in this subset of patients was 76.5%. The rates of revision surgery (10%) and complications were low. Conclusion. The A3 Fusion Nail demonstrated a favorable safety profile and achieved TTC arthrodesis at a rate consistent with historical data despite being used in a patient population at high risk for nonunion. In patients with bulk bone defects at high risk for nonunion, the A3 Fusion Nail demonstrated superior rates of fusion (76.5%) to those reported in the literature (50%).Level of Evidence: Level III: Retrospective cohort study.

Effect of bone morphogenetic protein-2/hydroxyapatite on ankle fusion with bone defect in a rabbit model: a pilot study

Background

Revision ankle-fusion surgery after a failure of total ankle arthroplasty has a problem with bone-defect management by implant removal. For the reconstruction of bone defects, autogenous bone often causes minor and major complications. Recombinant human-bone morphogenetic protein-2 (rhBMP-2) plays essential roles in bone regeneration strategies, and hydroxyapatite (HA) is beneficial as the rhBMP-2 carrier. In this study, we evaluate whether rhBMP-2/HA can replace autogenous bone in a rabbit ankle-fusion model with distal tibia bone defect.

Methods

The bone defect was created in the distal tibia. The ankle fusion was performed by a cannulated screw from lateral malleolus and various treatments on bone defect. Thirty male white New Zealand rabbits were divided into three groups of 10 animals on each group dependent on treatment methods as control group (no treatment into defect), auto-bone group (autogenous bone treatment), and rhBMP-2/HA group (40 μL of 1 μg/mL rhBMP-2/100 μL HA). Bone formation on defect and the union of the ankle joint were evaluated by X-ray, micro-CT, and histological analysis at 8 weeks and 12 weeks, postoperatively.

Results

Radiographic assessment found the control and auto-bone groups still had the bone defect present, but rhBMP-2/HA group showed complete replacement of the defect with newly formed bone at 12 weeks. Micro-CT showed significantly higher new bone formation within the defect in the rhBMP-2/HA group than in the auto-bone and control groups at 8 weeks (p > 0.05 and p < 0.01, respectively) and 12 weeks (p < 0.05, p < 0.001, respectively). Fusion rate (%) analysis of micro-CT showed a higher percentage of union in the rhBMP-2/HA group than in the auto bone and control groups at 8 weeks (p > 0.05, p < 0.001, respectively) and 12 weeks (p < 0.001 and p < 0.001, respectively). The histological showed the highest osteointegration between distal tibia and talus in the rhBMP-2/HA group at 12 weeks.

Conclusions

This study indicated that rhBMP-2/HA showed much better bone fusion than did the autogenous bone graft and was effective in promoting fusion rate and improving the quality of the ankle joint fusion.

Midterm Results of Radiographic and Functional Outcomes After Tibiotalocalcaneal Arthrodesis With Bulk Femoral Head Allograft

Background: Tibiotalocalcaneal (TTC) arthrodesis implementing adjunctive allografts is a method of limb salvage for patients with complex hindfoot osseous deficits, though outcome results are limited. The purposes of this study were to assess functional and radiographic outcomes after TTC arthrodesis with femoral head allograft and retrospectively identify prognostic factors. Methods: The authors reviewed 24 TTC arthrodesis procedures with bulk femoral head allografts performed by a single surgeon from 2004 to 2016. Radiographic union at the ankle and subtalar joints along with stability of the allograft were assessed. Patients who had clinically successful arthrodeses were contacted to score the Foot and Ankle Ability Measure-Activities of Daily Living (FAAM-ADL) questionnaire, Visual Analog Scale (VAS) for pain, and Short Form-12 (SF-12) at a mean of 58.0 months (range, 28-102) postoperatively. Results: Complete radiographic union of involved joints was achieved in 15 patients (63%) and in 75% (36/48) of all joints; 21 ankles (88%) were assessed to be radiographically stable at final follow-up. Three patients (13%) underwent revision arthrodesis at a mean of 18.9 months postoperatively, and 21 patients (88%) did not require additional surgery as of final follow-up. Patients significantly improved to a mean FAAM-ADL score of 71.5 from 36.3 (P < .001). The mean VAS for pain significantly improved from 77.2 to 32.9 (P < .001). Male sex (P = .08) and a lateral operative approach (P = .03) both resulted in worse outcomes. Conclusion: Use of a femoral head allograft with TTC arthrodesis can offer improved functional scores and sustained radiographic outcomes.Level of Evidence: Level IV: Case series.

Talectomy as Part of Chronic Foot and Ankle Deformity Correction Procedure: A Retrospective Study

Severe foot and ankle deformities can be associated with high complication rates and impaired quality of life in patients. Surgical correction using a talectomy procedure has previously been described in many lower extremity pathologies and is a powerful tool for the correction of severe foot and ankle deformity. This study aimed to describe the role of talectomy and the outcomes of this procedure in patients presenting with severe foot and ankle deformity. A review of 45 patients undergoing talectomy by a single surgeon was completed. Data extracted included the cause of deformity, history of infection, body mass index, and relevant comorbidities. Outcome measures of interest were minor or major complications and limb functionality at final follow-up. Statistical analysis was performed by using a Wilcoxon rank sum test and a Fisher exact test looking at variables affecting selected outcome measures. Limb salvage occurred in 38 of 45 patients (84.4%). Patients with an infection history had 89% lower odds of a functional limb at final follow-up (p = .0389). Six of 7 patients (85.7%) who ultimately underwent amputation had a history of prior infection. Women had 8.25 times higher odds of having a functional limb compared with men (p = .047). All 13 patients with major complications had neuropathy (p = .024). Patients with chronic lower extremity deformities can successfully be treated with a talectomy as a part of the reconstructive procedure. This is a challenging patient population that is associated with a high complication rate. Patients with a history of infection should be counseled on the possibility of requiring major amputation.

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.