A Study of Tibial Cyst Formation in Modular Stemmed Total Ankle Arthroplasty: Exploring a Possible Relationship to Smooth and Porous Coating on the Stem Segments.

Vertical fixation through stemmed components has been a successful strategy in total ankle arthroplasty. Research in hip replacement surgery has demonstrated increased rates of stress shielding, aseptic loosening, thigh pain, and cystic formation around stemmed femoral implants extensively coated with porous surfaces. While some ankle prostheses have integrated porous coating technology with stemmed tibial implants, there is little to no research investigating the potential negative effects of bone bonding to the tibial stems and possible impact on tibial cyst formation. We performed a retrospective cohort study comparing the incidence of periprosthetic tibial cyst formation in smooth versus fully porous-coated stemmed tibial implants after undergoing total ankle implant arthroplasty. Radiographs were compared for postoperative rates of tibial cyst formation and bone bonding to the tibial stems. Relative risk for reoperation between the smooth and porous-coated implants was investigated. The smooth-stem group showed no incidence of tibial cyst formation nor signs of significant bone bonding to the tibial stems; however, the follow-up matched porous-coated group showed a rate of 63% of cystic formation with associated evidence of bone bonding on final radiographic follow-up (p < .01). Relative risk for reoperation was 0.74. Despite a higher incidence of tibial cyst formation in the stemmed ankle arthroplasty groups with porous coating, reoperation rates were similar. We theorize that the proximal bonding to the porous stem surface could impact the distal stems and result in the observed increase in cyst formation.

Comparison of Dynamic Versus Static Locked Retrograde Tibiotalocalcaneal Arthrodesis With Intramedullary Nail Fixation: Evaluation of the RAIN Database.

Hindfoot osteoarthritis (OA) or deformity involving the ankle and subtalar joint is a disabling condition. Tibiotalocalcaneal (TTC) fusion is an effective salvage option in pathologies where total ankle replacement is contraindicated. The purpose of this study is to compare the union rate of the ankle joint in proximal static versus dynamically locked retrograde intramedullary nail fixation for tibiotalocalcaneal arthrodesis. An institutional review board-approved comprehensive chart and radiographic review was performed. TTC arthrodesis performed in patients with OA, post-traumatic arthritis, or deformity corrected by retrograde nail were included. Patients with Charcot arthropathy, failed joint replacement, neuropathy, or avascular necrosis were excluded. The primary outcome was ankle joint union with secondary measure of mean time to fusion. A total of 60 patients met inclusion criteria with 30 in the static group (SG) and 30 in the dynamic group (DG). The average age of the static group (SG) and dynamic group (DG) was 56.9 and 54.1 years, respectively. Mean body mass index was 34.03 kg/m2 for SG and 33.43 kg/m2 for DG. The union rate of the ankle joint was slightly higher in the DG but not statistically significant [SG 83.3%, DG 86.6%, p > .05 (p = .83)]. Time to fusion (TTF) in SG was 111.6 days compared to 97.2 days in DG. Dynamically locked intramedullary nails allow continued compression across the arthrodesis site as fusions remodel. Time to union and union rate of the ankle joint was superior in the dynamic group but this was not statistically significant. In this cohort, union rates were excellent in both groups, and no statistically significant difference was seen in the number of nonunions.

Accuracy of CT-Derived Patient-Specific Instrumentation for Total Ankle Arthroplasty: The Impact of the Severity of Preoperative Varus Ankle Deformity.

BACKGROUND: Significant preoperative varus tibiotalar deformity was once believed to be a contraindication for total ankle arthroplasty (TAA). Our primary goal was to evaluate the influence of increasing preoperative varus tibiotalar deformity on the accuracy of final implant positioning using computed tomography (CT)-derived patient-specific guides for TAA. METHODS: Thirty-two patients with varus ankle arthritis underwent TAA using CT-derived patient-specific guides. Patients were subcategorized into varying degrees of deformity based on preoperative tibiotalar angles (0°-5° neutral, 6°-10° mild, 11°-15° moderate, and >15° severe). Postoperative weightbearing radiographs were used to measure coronal plane alignment of the tibial implant relative to the target axis determined by the preoperative CT template. Average follow-up at the time of data collection was 36.8 months. RESULTS: Average preoperative varus deformity was 6.06° (range: 0.66°-16.3°). Postoperatively, 96.9% (30/31) of patients demonstrated neutral implant alignment. Average postoperative tibial implant deviation was 1.54° (range: 0.17°-5.7°). Average coronal deviation relative to the target axis was 1.61° for the neutral group, 1.78° for the mild group, 0.94° for the moderate group, and 1.41° for the severe group (P = .256). Preoperative plans predicted 100% of tibial and talar implant sizes correctly within 1 size of actual implant size. Conclusion. Our study supports the claim that neutral postoperative TAA alignment can be obtained using CT-derived patient-specific instrumentation (PSI). Furthermore, final implant alignment accuracy with PSI does not appear to be impacted by worsening preoperative varus deformity. All but one patient (96.9%) achieved neutral postoperative alignment relative to the predicted target axis. LEVEL OF EVIDENCE: Level IV, Clinical Case Series.

Pedal Musculovenous Pump Activation Effectively Counteracts Negative Impact of Knee Flexion on Human Popliteal Venous Flow.

Knee scooters are commonly used for mobility instead of other devices. However, passive popliteal venous flow impedance has been observed with knee scooter usage ostensibly as a result of deep knee flexion. This study aimed to characterize the magnitude of impact knee flexion has on popliteal venous flow in relation to the degree of knee flexion when walking boot immobilized. Furthermore, the countervailing effect of standardized pedal musculovenous pump (PMP) activation was observed. Popliteal venous diameter and flow metrics were assessed with venous ultrasonography in 24 healthy individuals. Straight leg, crutch, and knee scooter positioning while wearing a walking boot and non-weight-bearing were compared. Flow was assessed with muscles at rest and with PMP activation. Of 24 participants, 16 (67%) were female. Twelve limbs (50%) were right sided. The mean age was 21.9 (SD = 3.0) years, and the mean body mass index was 21.9 (SD 1.9) kg/m2. Observer consistencies were excellent (intraclass correlation range = 0.93 to 0.99). No significant differences in mean vessel diameter, time-averaged mean velocity, and total volume flow occurred (all P > .01). Corresponding knee flexion effect sizes were small (range = -0.04 to -0.26). A significant decrease (-24%) in active median time-averaged peak velocity occurred between upright and crutch positions (20.89 vs 15.92 cm/s; P < .001) with a medium effect size (-0.51). PMP activation increased all flow parameters (all P < .001), and effect sizes were comparatively larger (>0.6) across all knee flexion positions.Clinical Significance: Knee flexion has a small to medium impact on popliteal venous return in healthy patients. Active toe motion effectively counters the negative effects of gravity and knee flexion when the ankle is immobilized.Levels of Evidence: Therapeutic, Level IV.

Lateral Instability in Total Ankle Arthroplasty: A Comparison Between the Brostrom-Gould and Anatomic Lateral Ankle Stabilization (ATLAS).

BACKGROUND: Lateral ankle instability is not uncommon after osseous cuts and soft tissue releases are performed during Total Ankle Arthroplasty (TAA), particularly with varus malalignment. The purpose of the present study was to compare the outcomes of ankles that underwent TAA with concurrent Brostrom-Gould (BG) or Anatomic Lateral Ankle Stabilization (ATLAS) at a minimum of 1-year follow-up. METHODS: Thirty-eight TAAs underwent BG (21 INFINITY, 4 CADENCE) or ATLAS (13 INBONE-2) between August 2015 and February 2019 at a single institution and were at least 1 year postoperative (mean 18.3 months, range: 12-40). Baseline patient demographics, characteristics, and operative factors were assessed via medical record and chart reviews. Radiographs parameters were measured preoperatively, at 6 weeks postoperative, and during the latest follow-up. Revisions, reoperations, and complications were classified according to the criteria established by Vander Griend et al and Glazebrook et al, respectively. Univariate and multivariate analyses were performed. RESULTS: Survivorship for TAA with concurrent BG/ATLAS was 97%. Overall, TAA with concurrent BG had higher incidences of early TAA revision (4%), recurrent instability (4%), reoperation (16%), and complications (29%) compared to ATLAS. Postoperative coronal and sagittal tibiotalar alignment changes were significant for both groups (P < .001, P = .014); however, the differences were greater for ATLAS (P = .045, P < .001). CONCLUSION: The present study is the first to compare outcomes between techniques for addressing ankle instability in the TAA population. At short-term follow-up, anatomic reconstruction produced better outcomes than the traditional BG procedure. Additional comparative studies between techniques to address instability in the TAA population are warranted. LEVEL OF EVIDENCE: Level III: Retrospective cohort study.

The Medial Gastrocnemius Recession, an Alternative Surgical Treatment for Isolated Gastrocnemius Contracture: A Cadaver Study With Discussion Emphasizing Variable Conjoint Tendon Anatomy.

BACKGROUND: Gastrocnemius recession is a popular procedure utilized to treat chronic conditions related to isolated gastrocnemius contracture (IGC). Recent anatomical research detailing variable gastrocsoleus tendon morphology has raised important questions regarding the safety of some traditional recession procedures. Alternative gastrocnemius recession strategies may produce comparable dorsiflexion improvement results while avoiding the surgical risk related to conjoint tendon anatomical variability. METHODS: Ten matched cadaver pairs were randomized to receive either a medial gastrocnemius recession (MGR) procedure or a gastrocnemius intramuscular recession "Baumann" procedure. Postoperative dorsiflexion improvement was measured and then compared between groups. Detailed postoperative surgical dissections were performed to assess structures at risk, conjoint tendon morphology, and anatomical symmetry. RESULTS: Medial gastrocnemius recession and Baumann procedures were equally effective at producing significant increases in passive ankle dorsiflexion. No sural nerve injuries were observed. Thirty-five percent of specimens showed direct muscular fusion of at least a portion of the distal gastrocnemius muscular tissue to the adjacent soleus. CONCLUSION: The MGR procedure produced comparable dorsiflexion improvement results to the Baumann procedure in our cadaver model. Surgeons must account for certain conjoint tendon anatomical variants when surgically treating IGC as traditional recession methods risk tendo-Achilles overlengthening. LEVELS OF EVIDENCE: Level V: Cadaver Study.

Direct Plantar Approach to Plantar Plate Repair and Associated Wound Complications.

BACKGROUND: Lesser toe metatarsophalangeal joint (MTPJ) instability, secondary to plantar plate tear, has been the focus of numerous recent publications, the majority reporting on repair through a dorsal approach. A plantar approach has been described with the advantage of direct ligamentous repair or repair to bone, which follows conventional techniques employed throughout the body. Previous clinical studies have shown success in deformity correction and the longevity of both approaches. The proponents of the dorsal approach advocate that indirect repair of the plantar plate avoids perceived risks of complications with a plantar incision without evidence of superior outcomes. The purpose of this study was to investigate the safety and efficacy of the direct plantar approach to plantar plate repairs (PPRs) by reporting the rate of specific complications in a large clinical series. METHODS: This was the institutional review board (IRB) approved retrospective study of 204 PPRs in 185 patients (194 lesser MTP, 10 hallux MTP) with an average age of 56 and a mean body mass index (BMI) of 28. Surgical technique involved repair with absorbable braided suture (88%) versus suture anchor (12%) with or without MTPJ pinning (80%). Mean follow up was 53 weeks (range 5-170). Patients were screened for associated risk factors, including diabetes mellitus (8%), tobacco use (5%), neuropathy (1%), and additional concurrent procedures (96%). Complications were defined as superficial or deep infection, painful scars, and reoperation. Analysis was conducted using the Wilcoxon-Mann-Whitney test or Fisher's exact tests for continuous and categorical variables, respectively. Risk factors were analyzed using univariate logistic analysis to produce odds ratios (OR) with a 95% confidence interval (CI) and an inclusion criterion of a P-value, P > .2 for multivariate analysis as determined by Wald tests (significance at P < .05 for final modeling). RESULTS: Overall, there were 31 total complications (15%) demonstrated by 14 superficial infections (6.8%) and 17 painful scars (8.3%) along with three reoperations (1.4%). All reoperations were performed for deformity or instability, not scar revision. There were no deep infections. No increased odds of complications were found with suture anchor repair, MTPJ pinning, neuropathy, or diabetes. Patients that used tobacco had 7.5 (CI 1.66, 34.06) the odds of developing any wound complication compared with nonsmokers. Tobacco use was also found to significantly increase the odds of superficial infection by 9.8 (CI 2.08, 46.15). There was no increase in painful scars or reoperation in tobacco users. This study did not find an increased complication rate with additional ipsilateral procedures performed at the time of surgery. CONCLUSION: To our knowledge, this is the largest study evaluating the direct plantar approach to PPR as well as the evaluation of associated complications with the plantar incision. With low complication and minimal reoperation rates, the results of this study have demonstrated the clinical viability of plantar-based incisions. Previous studies have demonstrated the success of PPR and correction of deformity with a direct approach. This case series further demonstrates the safety and efficacy of plantar-based incisions, particularly for direct PPRs. LEVEL OF EVIDENCE: IV Retrospective Case Series. CATEGORY: Lesser Toes.

Paediatric ankle cartilage lesions: Proceedings of the International Consensus Meeting on Cartilage Repair of the Ankle.

BACKGROUND: The evidence supporting best practice guidelines in the field of cartilage repair of the ankle are based on both low quality and low levels of evidence. Therefore, an international consensus group of experts was convened to collaboratively advance toward consensus opinions based on the best available evidence on key topics within cartilage repair of the ankle. The purpose of this article is to report the consensus statements on "Pediatric Ankle Cartilage Lesions" developed at the 2019 International Consensus Meeting on Cartilage Repair of the Ankle. METHODS: Forty-three international experts in cartilage repair of the ankle representing 20 countries convened to participate in a process based on the Delphi method of achieving consensus. Questions and statements were drafted within four working groups focusing on specific topics within cartilage repair of the ankle, after which a comprehensive literature review was performed and the available evidence for each statement was graded. Discussion and debate occurred in cases where statements were not agreed upon in unanimous fashion within the working groups. A final vote was then held, and the strength of consensus was characterised as follows: consensus: 51-74%; strong consensus: 75-99%; unanimous: 100%. RESULTS: A total of 12 statements on paediatric ankle cartilage lesions reached consensus during the 2019 International Consensus Meeting on Cartilage Repair of the Ankle. Five achieved unanimous support, and seven reached strong consensus (>75% agreement). All statements reached at least 84% agreement. CONCLUSIONS: This international consensus derived from leaders in the field will assist clinicians with the management of paediatric ankle cartilage lesions.

Terminology for osteochondral lesions of the ankle: proceedings of the International Consensus Meeting on Cartilage Repair of the Ankle.

BACKGROUND: The evidence supporting best practice guidelines in the field of cartilage repair of the ankle is based on both low quality and low levels of evidence. Therefore, an international consensus group of experts was convened to collaboratively advance toward consensus opinions based on the best available evidence on key topics within cartilage repair of the ankle. The purpose of this article is to report the consensus statements on "terminology for osteochondral lesions of the ankle" developed at the 2019 International Consensus Meeting on Cartilage Repair of the Ankle. METHODS: Forty-three international experts in cartilage repair of the ankle representing 20 countries were convened and participated in a process based on the Delphi method of achieving consensus. Questions and statements were drafted within four working groups focusing on specific topics within cartilage repair of the ankle, after which a comprehensive literature review was performed, and the available evidence for each statement was graded. Discussion and debate occurred in cases where statements were not agreed on in unanimous fashion within the working groups. A final vote was then held, and the strength of consensus was characterised as follows: consensus, 51%-74%; strong consensus, 75%-99%; unanimous, 100%. RESULTS: A total of 11 statements on terminology and classification reached consensus during the 2019 International Consensus Meeting on Cartilage Repair of the Ankle. Definitions are provided for osseous, chondral and osteochondral lesions, as well as bone marrow stimulation and injury chronicity, among others. An osteochondral lesion of the talus can be abbreviated as OLT. CONCLUSIONS: This international consensus derived from leaders in the field will assist clinicians with the appropriate terminology for osteochondral lesions of the ankle.

Osteochondral Lesions of the Tibial Plafond and Ankle Instability With Ankle Cartilage Lesions: Proceedings of the International Consensus Meeting on Cartilage Repair of the Ankle.

BACKGROUND: An international consensus group of experts was convened to collaboratively advance toward consensus opinions based on the best available evidence on key topics within cartilage repair of the ankle. The purpose of this article is to present the consensus statements on osteochondral lesions of the tibial plafond (OLTP) and on ankle instability with ankle cartilage lesions developed at the 2019 International Consensus Meeting on Cartilage Repair of the Ankle. METHODS: Forty-three experts in cartilage repair of the ankle were convened and participated in a process based on the Delphi method of achieving consensus. Questions and statements were drafted within 4 working groups focusing on specific topics within cartilage repair of the ankle, after which a comprehensive literature review was performed and the available evidence for each statement was graded. Discussion and debate occurred in cases where statements were not agreed on in unanimous fashion within the working groups. A final vote was then held. RESULTS: A total of 11 statements on OLTP reached consensus. Four achieved unanimous support and 7 reached strong consensus (greater than 75% agreement). A total of 8 statements on ankle instability with ankle cartilage lesions reached consensus during the 2019 International Consensus Meeting on Cartilage Repair of the Ankle. One achieved unanimous support, and seven reached strong consensus (greater than 75% agreement). CONCLUSION: These consensus statements may assist clinicians in the management of these difficult clinical pathologies. LEVEL OF EVIDENCE: Level V, mechanism-based reasoning.

Heterotopic Ossification Following Total Ankle Arthroplasty With Fourth-Generation Prostheses.

BACKGROUND: The purpose of the present study was to assess the radiographic incidence, location, and classification of heterotopic ossification (HO) in patients who underwent total ankle arthroplasty (TAA) with a 4th generation prostheses at a minimum of 1-year follow up. Baseline demographic, radiographic, and operative factors between patents with and without HO were compared. METHODS: Ninety ankles that underwent TAA with a 4th generation protheses, INFINITY (n = 62) or CADENCE (n = 28) were followed for an average of 23.7 (range, 12-49) months. Incidence and location of HO was assessed on weightbearing radiographs, and severity graded according to the modified Brooker classification. Data was compared between patents with and without HO to identity any predisposing factors. RESULTS: In 90 ankles that underwent 4th generation TAA, HO incidence was 55.6% (n = 50); 56.5% (n = 35) for INFINITY, and 53.6% (n = 15) for CADENCE. Twenty-five cases of HO were observed posteriorly, 16 anteriorly, and 9 combined. Severity was as follows; class I in 19 cases (38%), class II in 20 (40%), class III in 9 (18%) and class IV in 2 (4%). A single ankle required a non-revisional reoperation for HO debridement; reoperation rate of 2%. CONCLUSION: The present study suggests a similarly high incidence of HO after TAA with two different 4th generation protheses (INFINITY 56.5%, CADENCE 53.6%). A trend for differences in location and severity between the protheses may also be present. Given the paucity of literature, additional studies with longer follow-up are warranted to discern the significance of HO following TAA with 4th generation protheses. LEVEL OF EVIDENCE: Level III: Retrospective cohort study.

The INFINITY Total Ankle Prosthesis: Outcomes at Short-Term Follow-up.

BACKGROUND: The INFINITY total ankle prothesis remains the most widely used fourth-generation total ankle arthroplasty (TAA) system in the United States. The purpose of the present study was to assess radiographic outcomes for INFINITY at short-term follow-up. METHODS: All patients who underwent primary TAA with INFINITY between August 2015 and June 2018 at a single institution and who were at least 1 year postoperative were included. A total of 55 ankles with a mean follow up 22 months (range, 12-43 months) met the criteria. Weightbearing radiographs were assessed using coronal and sagittal alignment parameters preoperatively, at 6 to 8 weeks postoperatively, and at the most recent follow-up. Medical records and charts were reviewed and revisions, reoperations, and complications were classified according to the criteria established by Vander Griend et al and Glazebrook at el, respectively. RESULTS: Overall, INFINITY survivorship was 98.2%. Coronal and sagittal tibiotalar alignment improved after surgery (P < .001, P = .09, respectively), and was maintained during the latest follow-up (P = .62, P = .47, respectively). Only 1 ankle (1.8%) required early revision; while 5 (9.1%) indicated non-implant-related revision; 85.5% required no reoperation. In nineteen ankles (34.5%), postoperative periprosthetic lucency was observed; most were not progressive (17 ankles, 89.5%). Twelve complications (3 high grade, 3 intermediate, and 6 low grade) in 11 ankles (20%) were recorded according to the Glazebrook classification system. CONCLUSION: INFINITY survivorship was 98.2% at a mean of 1.8 years of follow-up, and only 1 ankle required prosthetic revision. Additional studies with longer follow-up are warranted for fourth-generation TAA prostheses. LEVELS OF EVIDENCE: Level IV: Case series.

The Role of Secondary Imaging Techniques for Assessing Bone Mineral Density in Elderly Ankle Fractures.

Elderly ankle fractures in the elderly represent a substantial healthcare burden. Dual-energy x-ray absorptiometry (DXA) is the gold standard for diagnosis of osteoporosis. However, there is emerging research regarding secondary imaging techniques to evaluate bone mineral density (BMD). The purpose of this systematic review was to summarize the role of secondary imaging techniques for measuring BMD in elderly ankle fractures. A literature search was undertaken using relevant search terms. Articles were screened for suitability and data extracted where studies met inclusion criteria and were of sufficient quality. Eight studies were included in the systematic review. Computed tomography (CT) may have a role in preoperative surgical planning, provide an explanation for injury patterns in elderly patients, and may be correlated with clinical outcomes. High-resolution peripheral quantitative CT may be better suited than DXA for the assessment of ankle fractures due to the resolution of the image and its ability to distinguish between bone compartments, as well as provide a more accurate estimation of bone quality. Quantitative ultrasound has shown promise as a tool for measuring BMD in patients with osteoporosis, but is not able to detect osteoporosis in patients with ankle fractures. This paper helps define the role of each modality in the spectrum of care in the evaluation of osteoporosis as it pertains to elderly ankle fractures.

The Safety Profile of Same-Day Outpatient Total Ankle Arthroplasty.

There has been significant change in the health care policy in the United States in recent years with an increasing focus on health care costs and patient satisfaction. One strategy of cost containment is to transition outpatient surgery away from high cost hospital environments. Total ankle arthroplasty has begun the evolution to outpatient settings; however, there is limited published literature on the results of outpatient total ankle arthroplasty (TAA). The purpose of the present study was to review the safety profile of same day outpatient TAA at an ambulatory surgery center. A review of consecutive patients who underwent same day outpatient TAA for end-stage ankle arthritis with a minimum of 12 months' follow-up was performed. The primary outcomes assessed were the incidence of perioperative adverse medical events, hospital admissions related to the procedure, and postoperative complications (minor and major). Univariate analyses were performed. Fifty-one patients who underwent same-day TAA between June 2016 and July 2018 were included; mean follow-up was 20.7 months (± 7.6). The mean age at time of surgery was 56.5 years (± 7.2), with a mean body mass index of 30.4 (± 5.3). Overall, there were no perioperative adverse medical events or hospital admissions related to the procedure. Five minor complications (9.8%) and 7 major (13.7%) were recorded. Of the major complications, only 1 required TAA revision. Implant survivorship during the most recent follow-up was 98%. The present study suggests that TAA can be performed safely in an outpatient ambulatory setting. Additional comparative studies with larger TAA cohorts and patient reported outcomes are warranted.

Total Ankle Arthroplasty With Anatomic Lateral Ankle Stabilization (ATLAS) in Moderate and Severe Pre-operative Varus Alignment.

The purpose of the present study was to assess the early clinical and radiographic outcomes for patients who underwent TAA and Anatomic Lateral Ankle Stabilization (ATLAS) using synthetic graft for instability in moderate and severe preoperative varus alignment. Seven ankles with moderate or severe varus alignment underwent TAA with a 3rd generation prothesis (INBONE-2) and ATLAS using synthetic graft between September 2018 and February 2019 at a single institution, and were at least 1 year postoperative (mean 13.3 months, range 12-15). Medical records and charts were reviewed for revisions, reoperations, and complications. Weightbearing radiographs were assessed using tibiotalar alignment parameters preoperatively, and during the latest follow-up. Survivorship for INBONE-2 with ATLAS was 100%; recurrent instability was not observed. Symptomatic talonavicular joint arthritis was recorded for a single patient 12 months postoperatively; no revisions, or reoperations were performed. Coronal alignment improved significantly from 17.7 ± 9.3 (range, 10.1-33.6) to 2.3 ± 1.2 (range, 0.9-4.4) degrees (p < .006), and all ankles achieved neutral alignment in a single stage. Regarding sagittal alignment, 2 ankles (28.5%) were translated anteriorly and the rest were neutral (71.5%) preoperatively. Significant posterior translation was observed and during the latest follow-up, 4 ankles were neutral (57.1%) and 3 posterior (42.9%) (p < .009). Satisfactory outcomes were observed at a minimum of 1-year follow-up for patients with moderate or severe varus alignment who underwent TAA with INBONE-2 and ATLAS. ATLAS may afford advantages over previously described repair techniques. Comparative studies between the Brostrum-Gould and ATLAS are warranted.

Intermediate-Term Outcomes of a Third-Generation, 2-Component Total Ankle Prosthesis.

BACKGROUND: Short-term outcomes for the INBONE I and INBONE II tibial stems have been favorable. The INBONE-II talus has been shown to have lower reoperation and failure rates compared to its predecessor at short term follow-up. The purpose of the present study was to assess mid-term outcomes for the third generation, two component total ankle prosthesis at 5 to 9 years follow-up, evaluating both the tibial and talar components. METHODS: All patients who underwent primary total ankle arthroplasty (TAA) with INBONE-II between July 2010 and July 2014 at a single institution and who were at least 5 years postoperative were included. A total of 15 ankles with a mean follow-up of 85 months (range, 61-113 months) met the criteria. Radiographs were assessed using coronal and sagittal alignment parameters preoperatively, at 6 weeks postoperatively, and at the most recent follow-up. Medical records were reviewed and revisions, reoperations, and complications were classified according to the criteria established by Vander Griend et al and Glazebrook et al, respectively. RESULTS: The survivorship of the prosthesis at a mean of 85 months was 93.7%. The coronal and sagittal tibiotalar alignments 6 weeks after surgery were 2.1 degrees (P = .081) and 36% (P = .15), respectively. Maintenance of this alignment was observed during the latest follow-up (P = .684 and P = .837, respectively). One ankle (6.7%) required early component revision, while 4 (26.7%) required a non-implant-related revision. Six complications (2 high grade, 1 intermediate, and 3 low) in 5 ankles (33.3%) were recorded according to the Glazebrook classification system. CONCLUSION: The present study is the first to report midterm follow-up after TAA with this third-generation, 2-component prothesis. High survivorship, maintenance of correction, and a low incidence of major complications were observed in this small case series. The most common complication overall was lateral gutter impingement, which accounted for the majority of the nonrevisional reoperations. LEVEL OF EVIDENCE: Level IV, case series.

Bone Mineral Density Testing in Patients Undergoing Total Ankle Arthroplasty: Should We Pay More Attention to the Bone Quality?

Total ankle arthroplasty (TAA) has become one of the standard treatments for end-stage ankle arthritis. Long-term TAA survivorship is reported from 63% to 95%, with aseptic loosening being the most common mode of failure. Several studies have shown that low bone mineral density (BMD) of the hip affects the longevity of prosthetic implants. The role of Dual energy X-ray absorptiometry for TAA has not been established. The purpose of this review was to define the role of BMD in TAA outcomes and the role of Dual energy X-ray absorptiometry in measuring periprosthetic BMD. There is a paucity of information and published literature regarding the relationship between BMD and TAA. From attempting this systematic review, we hope to highlight that much of the focus in total ankle arthroplasty has emphasized implants and relatively little has focused on the quality of bone into which the prostheses are implanted.

Short- to Midterm Follow-up of Cemented Total Ankle Replacement Using the INBONE II: A Retrospective Chart Review.

Background: Total ankle arthroplasty is a viable option for the treatment of end stage ankle arthritis. The purpose of this study is to report on the mid-term results with a cemented total ankle prosthesis, the Inbone™ II implant over a 5 year period. Methods: A retrospective, single-center chart and radiographic review of all patients with end stage ankle arthritis treated with Inbone™ II TAR) as the primary index procedure from 12/1/2012 to 3/1/2017. Clinical data were evaluated at 3 month, 6 month, 1 year and subsequent intervals for the study period. Preoperative diagnosis, pertinent patient demographics adjunctive procedures, implant associated complications, subsequent surgeries, and revisions were recorded. Results: 121 total ankles met our inclusion criteria. Patients had an INBONE™ II TAR implant placed with bone cement with a minimum of a 12 months follow up. Average age was 62.88 (range, 32-87) years, average body mass index was 32.74 (range, 21.8-56.04) kg/m2 and average follow up was 28.51(range, 12-69) months. Using the COFAS complication classification there were 14 minor, 11 moderate, and 5 major complications. 6/121 (5.0%) revisions which included: polyethylene exchange, device explant/fusion, and antibiotic spacer in situ. No complications over the course of this study ended in amputation. Conclusion: Total Ankle Arthroplasty utilizing the cemented INBONE™ II yielded good midterm results with regards to minor, moderate, and major complications. Rate of revision 6/121 (5.0%) was within the reported range with only 5 patients converted to fusion during the study period resulting in a 95% survivability at mid-term follow up.Levels of Evidence: Level IV: Retrospective case series.

Accuracy of Weightbearing CT Scans for Patient-Specific Instrumentation in Total Ankle Arthroplasty.

BACKGROUND: Total ankle arthroplasty (TAA) is a popular and viable option for end-stage ankle arthritis. Posttraumatic arthritis is the most common etiology of ankle arthritis, which creates the additional challenge of osseus deformity. Accuracy and reproducibility in placing the implant on the mechanical axis has been shown to be paramount in all joint arthroplasty including total ankle replacement. Patient-specific preoperative navigation is a relatively new technology for TAA, and up until this past year has been based off of nonweightbearing (NWBCT) or simulated weightbearing computed tomography (WBCT). Our institution has created a protocol to use WBCT in the preoperative patient-specific navigation for TAA using the Prophecy system. The purpose of our study was to compare the accuracy and reproducibility of implant alignment and size using WBCT vs prior studies using NWBCT for the Prophecy reports. METHODS: All patients from July 2019 through October 2020 who underwent TAA were evaluated. Inclusion criteria consisted of primary TAA using patient-specific preoperative navigation who had postoperative radiographs in the 4-6-week time frame. Prophecy predictions and measurements were then compared to actual implant placement and size. RESULTS: Ten patients met our inclusion criteria of WBCT Prophecy preoperative planning using 2 different implant systems. Preoperative deformities in this cohort were small. The average postoperative coronal alignment was 0.84 degrees, range 0.19 to 2.4 degrees. Average postoperative sagittal plane deformity was 1.9 degrees, range 0.33 to 5.05 degrees. Tibial component size was properly predicted in all patients, talar component in 9 of 10. CONCLUSION: This initial report supports accuracy and reproducibility in preoperative patient-specific navigation when using WBCT for TAA with these implants. All TAAs were within the intended target of less than 5 degrees varus or valgus. LEVEL OF EVIDENCE: Level III, retrospective comparative analysis.

Risk Factors for Early Failure of Fourth Generation Total Ankle Arthroplasty Prostheses.

A number of 2-component, fourth generation total ankle arthroplasty (TAA) prostheses have been introduced to the market in the past few years, as the popularity and indications for TAA have continued to expand. The purpose of the present study was to identify independent risk factors for the early failure of fourth generation TAA prostheses. A total of 97 ankles underwent TAA with a fourth generation prostheses (INFINITY, CADENCE) between August 2015 and June 2018 at a single institution and were at least 6 months postoperative (mean 18.3 months, range 6-43). The primary outcome assessed was the need for revision surgery, defined as removal of 1 or both metal components for any reason, excluding infection. Baseline patient demographics, characteristics, radiographic alignment parameters, and distal tibia cortical bone thickness (CBT) were assessed. Revisions, reoperations, and complications were classified according to the criteria established by Vander Griend et al and Glazebrook et al, respectively. Univariate and multivariate analyses were performed. Three ankles (3.1%) underwent revision surgery for aseptic loosening at a mean of 24.3 (range, 16-31) months; all had a CBT <4 mm. Independent predictors for reoperation were CBT <4 mm, presence of diabetes, and ipsilateral hindfoot fusion (p = .04). No associations were identified for purported risk factors (age, body mass index, and coronal deformity). The present study is the first to suggest a potential relationship between reduced CBT of the distal tibia, and TAA failure. Additional studies are warranted to better understand the role of bone density in TAA survivorship.