Effect of Gender Differences on Patient-Reported Outcomes and Complications in Total Ankle Replacement

BACKGROUND

The purpose of this study was to evaluate gender differences in patient outcomes and complications following total ankle replacement (TAR).

METHODS

Consecutive patients who underwent primary TAR from July 2007 through May 2016 were prospectively followed and retrospectively reviewed. Demographic, operative, patient-reported outcomes (PROs), and complication data were collected and analyzed. PROs included the visual analog scale (VAS), 36-Item Short-Form Health Survey (SF-36), American Orthopaedic Foot & Ankle Society (AOFAS) hindfoot scale, and Short Musculoskeletal Function Assessment (SMFA). A total of 475 patients were evaluated, including 248 males (52.2%) and 227 females (47.8%) with an average of 56.8 months follow-up.

RESULTS

Women were more likely to have inflammatory arthritis (13.7% vs 2.8%; P < .01) and significantly worse preoperative SF-36 total, SF-36 mental health component, AOFAS total, AOFAS pain, SMFA function, and SMFA bother scores (all P < .05). Both genders demonstrated significant improvement in PROs at 1, 2, and 5 years. The magnitude of improvement was similar between genders for all PROs (all P < .05) with the exception of SF-36 physical function, which was greater in men. Females underwent more nonrevision reoperations (32.2% vs 22.6%; P = .0191), but there was no significant difference in failure rates (male 7.3% vs female 3.5%; P = .07). The reoperation and failure rates at 2 years postoperation were 10.1% and 1.6% for men and 18.5% and 0.9% for women, respectively.

CONCLUSION

Women undergoing TAR were more likely to have worse preoperative PROs and higher rates of nonrevision reoperations, which remains true when controlling for their increased incidence of inflammatory arthritis. However, women reported similar improvements in PROs and had similar prosthetic survival rates as men. Increased understanding of these disparities, combined with gender-based interventions, may further advance patient outcomes.

LEVEL OF EVIDENCE

Level III, therapeutic, retrospective comparative series.

Immune cell profiling in the joint following human and murine articular fracture

OBJECTIVE

Human and in vivo animal research implicates inflammation following articular fracture as contributing to post-traumatic arthritis. However, relevant immune cell subsets present following injury are currently undefined. Immunophenotyping human and murine synovial fluid may help to identify immune cell populations that play key roles in the response to articular fracture.

METHODS

Immunophenotyping by polychromatic flow cytometry was performed on human and mouse synovial fluid following articular fracture. Specimens were collected in patients with closed ankle fracture at the time of surgical fixation and from C57BL/6 mice with closed articular knee fracture. Immune cells were collected from injured and uninjured joints in mice via a novel cell isolation method. Whole blood samples were also collected. Immunohistochemistry (IHC) was performed on mouse synovial tissue to assess for macrophages and T cells.

RESULTS

Following intra-articular fracture, the prominent human synovial fluid immune cell subset was CD3+ T cells, containing both CD4+ and CD8+ T cells. In mice, infiltration of CD45+ immune cells in synovial fluid of the fractured limb was dominated by CD19+ B cells and CD3+ T cells at 7 days after intra-articular fracture. We also detected adaptive immune cells, including macrophages, NK cells, dendritic cells and monocytes. Macrophage and T cell findings were supported by IHC of murine synovial tissue.

CONCLUSIONS

Determining specific cell populations that mediate the immune response is essential to elucidating the chain of events initiated after injury and may be an important step in identifying potential immune signatures predictive of PTA susceptibility or potential therapeutic targets.

Total ankle arthroplasty and ankle arthrodesis in rheumatic disease patients: An analysis of outcomes and complications using the National Inpatient Sample (NIS) database

INTRODUCTION

Rheumatoid arthritis (RA), can manifest as an inflammatory arthropathy in the ankle. As a result, this study sought to examine the role of RA with respect to complications in patients undergoing either total ankle arthroplasty or ankle arthrodesis by utilizing the National Inpatient Sample to assess for correlations.

METHODS

Admissions for TAA and AA were extracted from the National Inpatient Sample using primary ICD-9-CM diagnosis codes. Patients aged 18-65 years with a duration of hospital stay of >3 days and isolated complications were included. Multivariable regression was then performed within matched groups to determine differences.

RESULTS

There was decreased risk of myocardial infarction, pulmonary embolism, surgical site infection, and urinary tract infection in patients with RA. Postoperative development of pneumonia was seen at a higher rate in patients with RA.

CONCLUSION

RA is not associated with a markedly increased complication burden in the appropriately chosen surgical candidate for ankle arthrodesis and ankle arthroplasty.

Effect of surface topography on in vitro osteoblast function and mechanical performance of 3D printed titanium

Critical-sized defects remain a significant challenge in orthopaedics. 3D printed scaffolds are a promising treatment but are still limited due to inconsistent osseous integration. The goal of the study is to understand how changing the surface roughness of 3D printed titanium either by surface treatment or artificially printing rough topography impacts the mechanical and biological properties of 3D printed titanium. Titanium tensile samples and discs were printed via laser powder bed fusion. Roughness was manipulated by post-processing printed samples or by directly printing rough features. Experimental groups in order of increasing surface roughness were Polished, Blasted, As Built, Sprouts, and Rough Sprouts. Tensile behavior of samples showed reduced strength with increasing surface roughness. MC3T3 pre-osteoblasts were seeded on discs and analyzed for cellular proliferation, differentiation, and matrix deposition at 0, 2, and 4 weeks. Printing roughness diminished mechanical properties such as tensile strength and ductility without clear benefit to cell growth. Roughness features were printed on mesoscale, unlike samples in literature in which roughness on microscale demonstrated an increase in cell activity. The data suggest that printing artificial roughness on titanium scaffold is not an effective strategy to promote osseous integration.

The Impact of Preoperative Mental Health and Depression on Outcomes After Total Ankle Arthroplasty

BACKGROUND

Preoperative mental health and depression have been shown to negatively impact patient-reported outcome measures after a broad array of orthopaedic procedures including total ankle arthroplasty. The hypothesis for this study was that decreased Short Form (SF)-36 Mental Component Summary (MCS) scores will modulate the impact of depression on patient-reported outcome measures after total ankle arthroplasty.

METHODS

All patients undergoing primary total ankle arthroplasty between January 2007 and December 2016 who were enrolled into a prospective outcomes study and who had at least 1-year minimum study follow-up were retrospectively reviewed. Patients were separated into 4 groups based on the presence or absence of an SF-36 MCS score of <35 points and diagnosis of depression. SF-36 Physical Component Summary (PCS) and MCS scores, Short Musculoskeletal Function Assessment (SMFA) function and bother components, and visual analog scale (VAS) pain were collected preoperatively and in the 1 to 2-year follow-up. The Wilcoxon rank sum was used to assess differences in outcomes by depression and low preoperative MCS scores. Multivariable models were then constructed to evaluate between-group differences in change scores according to preoperative SF-36 MCS scores and a diagnosis of depression, with adjustment for baseline patient and treatment characteristics.

RESULTS

Patients with depression and those with low preoperative MCS scores had significantly worse final outcome scores along with reduced improvement in SF-36 PCS and VAS pain scores compared with patients without these risk factors. Among patients with depression, low preoperative MCS scores helped to differentiate patients with poor final outcome scores. Similarly, in patients with low preoperative MCS scores, depression helped to differentiate patients with poor final outcome scores.

CONCLUSIONS

Although patients achieved significant improvements in functional outcomes regardless of cohort, decreased preoperative mental health modulated the impact of depression on outcomes. Patients with diminished preoperative mental health and depression are at an increased risk for sustaining smaller improvements in outcomes.

LEVEL OF EVIDENCE

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Clinical applications of custom 3D printed implants in complex lower extremity reconstruction

Background

Three dimensional printing has greatly advanced over the past decade and has made an impact in several industries. Within the field of orthopaedic surgery, this technology has vastly improved education and advanced patient care by providing innovating tools to complex clinical problems. Anatomic models are frequently used for physician education and preoperative planning, and custom instrumentation can assist in complex surgical cases. Foot and ankle reconstruction is often complicated by multiplanar deformity and bone loss. 3D printing technology offers solutions to these complex cases with customized implants that conform to anatomy and patient specific instrumentation that enables precise deformity correction.

Case presentation

The authors present four cases of complex lower extremity reconstruction involving segmental bone loss and deformity – failed total ankle arthroplasty, talus avascular necrosis, ballistic trauma, and nonunion of a tibial osteotomy. Traditional operative management is challenging in these cases and there are high complication rates. Each case presents a unique clinical scenario for which 3D printing technology allows for innovative solutions.

Conclusions

3D printing is becoming more widespread within orthopaedic surgery. This technology provides surgeons with tools to better tackle some of the more challenging clinical cases especially within the field of foot and ankle surgery.

Patient Characteristics of Possible Responders and Nonresponders to Total Ankle Arthroplasty

BACKGROUND

Characteristics of responders, or those who achieve a clinical improvement above the level of a minimal clinically important difference, have not been defined for total ankle arthroplasty (TAA). The purpose of this study was to determine patient characteristics that distinguish possible responders from possible nonresponders after TAA using criteria established for other arthroplasty surgeries.

METHODS

Patients undergoing TAA who were enrolled into a prospective study at a single academic center evaluating patient-reported outcomes were included. Patients were characterized as possible responders if the relative or absolute improvement in their 2-year follow-up Short Musculoskeletal Function Assessment (SMFA) function score was at least 50% or 20, respectively, compared with their preoperative score, consistent with Outcome Measures in Rheumatoid Arthritis Clinical Trials and the Osteoarthritis Research Society International (OMERACT-OARSI) responder criteria. Patient factors were then associated with possible responder or nonresponder status and a multivariable analysis was performed. A total of 491 patients with complete data and 2-year follow-up were included in this study.

RESULTS

Multivariable analysis demonstrated that a higher baseline 36-Item Short-Form Survey (SF-36) mental component summary (MCS) score (OR [95% CI], 1.02 [1.01, 1.04]; P = .003), indicating better mental health, was associated with being a possible responder to TAA. The presence of rheumatic disease (OR [95% CI], 0.38 [0.22, 0.67]; P = .001) was a significant predictor of being a possible nonresponder.

CONCLUSION

Our data reveal that a higher baseline SF-36 MCS score was associated with increased improvement in SMFA function scores, while rheumatic disease was associated with worse improvement in SMFA function scores after TAA. Patients with rheumatic disease or poor mental health may not achieve as favorable results after TAA and should be counseled appropriately.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Comparison of Tibiotalocalcaneal Arthrodeses Using a Sustained Dynamic Compression Nail Versus Nondynamized Nails

Background. Tibiotalocalcaneal (TTC) arthrodesis is a common treatment option for hindfoot arthritis and deformity. Loss of compression over time with statically locked nails may contribute to nonunion. A novel retrograde intramedullary nail with an internal pseudoelastic component has recently been used to provide sustained dynamic compression (SDC). The purpose of this study was to compare fusion rates and time to union between the SDC and nondynamized (ND) nails. Methods. All patients who underwent TTC arthrodesis with an intramedullary nail at a single institution from 2013 to 2017 and who had at least 1 year of follow-up were included in this study. Baseline patient and operative characteristics were collected and compared between the sustained SDC and ND nail groups. The rate of successful fusion, time to union, and complications were compared between the groups. Results. The SDC cohort had a significantly faster time to union by 3.9 months (P = .049). The SDC cohort had a higher fusion rate (78.0%) compared with the ND nail cohort (75.0%), although this was not statistically significant (P = .75). The SDC nail was used significantly (P < .05) more often in patients with known risk factors for nonunion, including female sex, smoking, revision surgery, prior trauma, and patients requiring 3D cage implants for significant bone loss. There were no differences between the groups in terms of complications. Conclusion. The SDC nail has been shown to achieve successful arthrodesis in a population at high risk for nonunion, using less hardware, and at a faster rate than ND nails. Level of Evidence: Level III: Retrospective, comparative study.

Salvage Arthrodesis for Failed Total Ankle Replacement

Salvage arthrodesis for failed total ankle replacement can be a successful procedure. The decision to perform salvage arthrodesis is based on many factors, but the following are the most important indications: severe loss of bonestock (tibia, talus, or both), inadequate soft tissue coverage, or the inability to eradicate an infection. With few revision implants on the market, salvage arthrodesis is currently the most common treatment for failed replacement and justification for revision ankle replacement is limited when any of these factors are present.

Arthroscopic Treatment of Osteochondral Lesions of the Talus With Microfracture and Platelet-Rich Plasma-Infused Micronized Cartilage Allograft

Osteochondral lesions of the talus (OLTs) are difficult to treat. Arthroscopic microfracture augmented with micronized cartilage (BioCartilage; Arthrex, Naples, FL) and platelet-rich plasma is emerging as a treatment for moderate-sized, well-contained full-thickness OLTs. This treatment may provide superior histologic results and is less technically demanding and yields less morbidity than an open osteochondral allograft or autograft transfer. This technique guide presents the senior author's preferred strategy for treatment of a moderate-sized OLT with arthroscopic microfracture and placement of micronized cartilage and platelet-rich plasma.

Systematic Review of Subtalar Distraction Arthrodesis for the Treatment of Subtalar Arthritis

BACKGROUND

Subtalar distraction arthrodesis (SDA) was developed as a means of treating the symptoms of subtalar arthritis. Despite almost 30 years of research in this field, many controversies still exist regarding SDA. The objective of this study was to present an overview of outcomes following SDA, focusing on surgical technique as well as clinical and radiographic results.

METHODS

MEDLINE and EMBASE were queried and data abstraction was performed by 2 independent reviewers. Inclusion criteria for the articles were (1) English language, (2) peer-reviewed clinical studies with evidence levels I to IV, (3) with at least 5 patients, and (4) reporting clinical and/or radiographic outcomes of SDA.

RESULTS

Twenty-five studies matched the inclusion criteria (2 Level III and 23 Level IV studies) including 492 feet in 467 patients. The most common indication for SDA was late complications of calcaneus fractures. Many different operative techniques have been described, and there is no proven superiority of one method over the other. The most commonly reported complications were nonunion, hardware prominence, wound complications, and sural neuralgia. All studies showed both radiographic and clinical improvement at the last follow-up visit compared with the preoperative evaluation. Pooled results (12 studies, 237 patients) demonstrated improved American Orthopaedic Foot & Ankle Society ankle-hindfoot scores with a weighted average of 33 points of improvement.

CONCLUSION

SDA provides good clinical results at short-term and midterm follow-up, with improvement in ankle function as well as acceptable complication and failure rates. Higher quality studies are necessary to better assess outcomes between different operative techniques.

LEVEL OF EVIDENCE

Level III.

Inflammatory cytokines and matrix metalloproteinases in the synovial fluid after intra-articular elbow fracture

BACKGROUND AND HYPOTHESIS

Post-traumatic elbow contracture remains a common and challenging complication with often unsatisfactory outcomes. Although the etiology is unknown, elevated or abnormal post-fracture synovial fluid cytokine levels may result in the migration of fibroblasts to the capsule and contribute to capsular pathology. Thus, the purpose of this study was to characterize the cytokine composition in the synovial fluid fracture hematoma of patients with intra-articular elbow fractures.

METHODS

The elbow synovial fluid fracture hematoma of 11 patients with intra-articular elbow fractures was analyzed for CTXII (C-terminal telopeptides of type II collagen [a cartilage breakdown product]) as well as 15 cytokines and matrix metalloproteinases (MMPs) including interferon γ, interleukin (IL) 1β, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12p70, IL-13, tumor necrosis factor α, MMP-1, MMP-2, MMP-3, MMP-9, and MMP-10. The uninjured, contralateral elbow served as a matched control. Mean concentrations of each factor were compared between the fluid from fractured elbows and the fluid from control elbows.

RESULTS

The levels of 14 of 15 measured cytokines and MMPs-interferon γ, IL-1β, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12p70, IL-13, tumor necrosis factor α, MMP-1, MMP-3, MMP-9, and MMP-10-were significantly higher in the fractured elbows. In addition, post hoc power analysis revealed that 10 of 14 significant differences were detected with greater than 90% power. The mean concentration of CTXII was not significantly different between groups.

CONCLUSIONS

These results demonstrate a proinflammatory environment after fracture that may be the catalyst to the development of post-traumatic elbow joint contracture. The cytokines with elevated levels were similar, although not identical, to the cytokines with elevated levels in studies of other weight-bearing joints, indicating the elbow responds uniquely to trauma.

Particulated juvenile articular cartilage allograft transplantation for osteochondral lesions of the knee and ankle

Introduction: Osteochondral lesions have been challenging to treat due to the limited regenerative capacity of native hyaline cartilage. Although surgical options are available, a newer technique, Particulated Juvenile Cartilage Allograft Transplantation (PJCAT) has shown promise for lesions of the knee and ankle. Short-term studies have been encouraging of its use, but there is still limited evidence of its long-term durability.Areas covered: This review will summarize the surgical options currently available for osteochondral lesions, outline the indications and contraindications of PJCAT, present the basic science and clinical evidence of the procedure, and describe the surgical approaches of this technique.Expert opinion: PJCAT is a promising method to treat osteochondral lesions. However, continued research is needed to document the efficacy of this technique and potential superiority over other techniques. Benefits include ease of application, potential for arthroscopic or minimally invasive delivery, no need for perpendicular access, no donor site morbidity, and delivery of viable chondrocytes in hyaline cartilage.

Results of Tibia and Fibula Osteotomies Performed Concomitant to Total Ankle Replacement

BACKGROUND

Neutral ankle alignment along with medial and lateral support are paramount to the success of total ankle replacement (TAR). Fibula, intra-articular medial malleolus, and supramalleolar tibia osteotomies have been described to achieve these goals; however, the literature is scant with outcomes and union rates of these osteotomies performed concomitant to TAR. The purpose of this study was to describe our results.

METHODS

A retrospective review was performed to identify patients who had a concomitant tibia, fibula, or combined tibia and fibula osteotomy at the same time as TAR. Routine radiographs were used to assess osteotomy union rates and changes in alignment. Outcomes questionnaires were evaluated preoperatively and at most recent follow-up. Twenty-six patients comprising 4% of the total TAR cohort were identified with a mean follow-up of 3.9 years.

RESULTS

There were 12 combined tibia and fibula osteotomies, 9 isolated tibia osteotomies, and 5 isolated fibula osteotomies. The union rate for these osteotomies was 92%, 100%, and 100%, respectively. Mean coronal alignment improved from 15.2 to 2.1 degrees (P < .001). There was significant improvement in patient-reported outcome scores, including Short Form-36, Short Musculoskeletal Function Assessment, and visual analog scale pain. There was 1 failure in the study.

CONCLUSION

These data demonstrate successful use of tibia, fibula, or combined tibia and fibula osteotomies at the same time as TAR in order to gain neutral ankle alignment. The overall union rate was 96% with significant improvement in alignment, pain, and patient-reported outcomes. We believe concomitant osteotomies can be considered a successful adjunctive procedure to TAR.

LEVEL OF EVIDENCE

Level III, retrospective comparative series.

Prospective Randomized Trial Comparing Mobile-Bearing and Fixed-Bearing Total Ankle Replacement

BACKGROUND

Outcomes of total ankle replacement for the treatment of end-stage ankle arthritis continue to improve. Debate continues whether a mobile-bearing total ankle replacement (MB-TAR) or a fixed-bearing total ankle replacement (FB-TAR) is superior, with successful outcomes reported long term for MB-TAR and at intermediate- to long-term follow-up for newer generation FB-TAR. Although comparisons between the 2 total ankle designs have been reported, to our knowledge, no investigation has compared the 2 designs with a high level of evidence. This prospective, randomized controlled trial conducted at a single institution compares patient satisfaction, functional outcomes, and radiographic results of the mobile-bearing STAR and the fixed-bearing Salto-Talaris in the treatment of end-stage ankle arthritis.

METHODS

Between November 2011 and November 2014, adult patients with end-stage ankle osteoarthritis failing nonoperative treatment were introduced to the study. With informed consent, 100 patients (31 male and 69 female, average age 65 years, range 35-85 years) were enrolled; a demographic comparison between the 2 cohorts was similar. Exclusion criteria included inflammatory arthropathy, neuropathy, weight exceeding 250 pounds, radiographic coronal plane deformity greater than 15 degrees, or extensive talar dome wear pattern ("flat-top talus"). Prospective patient-reported outcomes, physical examination, and standardized weightbearing ankle radiographs were obtained preoperatively, at 6 and 12 months postoperatively, and then at yearly intervals. Data collection included visual analog pain score, Short Form 36, Foot and Ankle Disability Index, Short Musculoskeletal Functional Assessment, and American Orthopaedic Foot & Ankle Society ankle-hindfoot score. Surgeries were performed by a nondesign team of orthopedic foot and ankle specialists with total ankle replacement expertise. Statistical analysis was performed by a qualified statistician. At average follow-up of 4.5 years (range, 2-6 years) complete clinical data and radiographs were available for 84 patients; 7 had incomplete data, 1 had died, 4 were withdrawn after enrolling but prior to surgery, and 4 were lost to follow-up.

RESULTS

In all outcome measures, the entire cohort demonstrated statistically significant improvements from preoperative evaluation to most recent follow-up with no statistically significant difference between the 2 groups. Radiographically, tibial lucency/cyst formation was 26.8% and 20.9% for MB-TAR and FB-TAR, respectively. Tibial settling/subsidence occurred in 7.3% of MB-TAR. Talar lucency/cyst formation occurred in 24.3% and 2.0% of MB-TAR and FB-TAR, respectively. Talar subsidence was observed in 21.9% and 2.0% of MB-TAR and FH-TAR, respectively. Reoperations were performed in 8 MB-TARs and 3 FH-TARs, with the majority of procedures being to relieve impingement or treat cysts and not to revise or remove metal implants.

CONCLUSION

With a high level of evidence, our study found that patient-reported and clinical outcomes were favorable for both designs and that there was no significant difference in clinical improvement between the 2 implants. The incidence of lucency/cyst formation was similar for MB-TAR and FH-TAR for the tibial component, but the MB-TAR had greater talar lucency/cyst formation and tibial and talar subsidence. As has been suggested in previous studies, clinical outcomes do not necessarily correlate with radiographic findings. Reoperations were more common for MB-TAR and, in most cases, were to relieve impingement or treat cysts rather than revise or remove metal implants.

LEVEL OF EVIDENCE

Level I, prospective randomized study.

Pathogenesis of Posttraumatic Osteoarthritis of the Ankle

Ankle osteoarthritis affects a significant portion of the global adult population. Unlike other joints, arthritis of the ankle often develops as a response to traumatic injury (intra-articular fracture) of the ankle joints. The full mechanism leading to posttraumatic osteoarthritis of the ankle (PTOAA) is poorly understood. These deficits in knowledge pose challenges in the management of the disease. Adequate surgical reduction of fractured ankle joints remains the gold standard in prevention. The purpose of this review is to thoroughly delineate the known pathogenesis of PTOAA, and provide critical updates on this pathology and new avenues to provide therapeutic management of the disease.

Management of Complications of Achilles Tendon Surgery

There are multiple techniques to treat tendon defects in the event end-to-end repair cannot be achieved after débridement. In general, the choice of treatment technique is based on size of the resultant gap. Although each treatment technique has literature to support its use, there are no data to support the use of one technique over another. Treatment should be based on the experience and discretion of the treating surgeon. This article proposes an algorithm for wound breakdown, infection, and rerupture after Achilles tendon surgery. This algorithm should be used as a guide.

Patients at Risk for Exceeding CJR Cost Targets After Total Ankle Arthroplasty

BACKGROUND

The Comprehensive Care for Joint Replacement (CJR) model includes total ankle arthroplasty (TAA), under which a target reimbursement is established. Whether this reimbursement is sufficient to cover average cost remains unknown. We hypothesized that a substantial number of TAAs still exceed cost targets, and that risk factors associated with exceeding the target cost could be identified preoperatively.

METHODS

Two hundred two primary TAAs performed at a single tertiary referral center under the CJR model from June 2013 to May 2017 were retrospectively reviewed. Patient demographics, comorbidities, outcomes, and costs were extracted from the electronic medical record using a validated structured query language (SQL) algorithm. A comparison cohort of 2084 CJR total hip arthroplasty (THA) and total knee arthroplasty (TKA) cases performed during the same period was also reviewed.

RESULTS

Twenty TAAs (10%) exceeded the target cost of care, significantly fewer than CJR THAs/TKAs (29%) performed during the same period (P < .0001). These patients did not differ significantly in age, sex, body mass index, number of Elixhauser comorbidities, or the American Society of Anesthesiologists score. The average cost for these patients was $17 338 higher than those who did not exceed the target cost, and they were less likely to be married or have a partner (45% vs 79%, P = .001). Non-Caucasian status also reached significance (P < .0001). Those exceeding the target cost had a significantly longer length of stay (2.6 vs 1.5 days, P < .0001) and were more likely to be discharged to either skilled nursing or a rehabilitation facility (60% vs 1%, P < .0001).

CONCLUSION

Even high-volume TAA centers still exceed target costs in up to 10% of cases, with length of stay, discharge location, and readmissions driving many of these events. Potential risk factors for excess cost include marital/partner status and non-Caucasian ethnicity, but further work is needed to clarify their effects and whether other risk factors exist.

LEVEL OF EVIDENCE

Level III, comparative study.

The Use of Bone Grafts, Bone Graft Substitutes, and Orthobiologics for Osseous Healing in Foot and Ankle Surgery

Achieving fusion in osseous procedures about the foot and ankle presents unique challenges to the surgeon. Many patients have comorbidities that reduce osseous healing rates, and the limited space and high weightbearing demand placed on fusion sites makes the choice of bone graft, bone graft substitute, or orthobiologic agent of utmost importance. In this review, we discuss the essential characteristics of grafts, including their osteoconductive, osteoinductive, osteogenic, and angiogenic properties. Autologous bone graft remains the gold standard and contains all these properties. However, the convenience and lack of donor site morbidity of synthetic bone grafts, allografts, and orthobiologics, including growth factors and allogenic stem cells, has led to these being used commonly as augments.

Algorithm for Management of Periprosthetic Ankle Fractures

BACKGROUND

Evidence on the management of and outcomes from periprosthetic fractures about a total ankle replacement (TAR) are limited. The purpose of this study was to develop an algorithm for the management of patients with postoperative periprosthetic fractures about a TAR.

METHODS

This was a retrospective analysis of patients undergoing a TAR from 2007 through 2017 with a subsequent periprosthetic fracture >4 weeks from index surgery. Implant stability was defined radiographically and intraoperatively where appropriate. Univariate and multivariate analyses were used to identify differences in outcomes. Thirty-two patients were identified with a remote TAR periprosthetic fracture with an average follow-up of 26 months (range, 3-104 months).

RESULTS

Most fractures were located about the medial malleolus (62.5%); the majority of fractures (75%) were deemed to have stable implants. Fractures of the talus always had unstable implants and always required revision TAR surgery (100%, P = .0002). There was no difference in patient-reported outcomes between stable and unstable fractures at an average of 36 months. In a multivariate analysis, fracture location (talus), less time to fracture, and implant type were found to be predictive of unstable implants ( P < .001). Implant stability was independently associated with the need for revision surgery ( P < .049). Nonoperative treatment was independently associated with treatment failure ( P < .001).

CONCLUSION

The majority of stable fractures about a TAR required operative fixation. Management with immobilization was fraught with a high rate of subsequent surgical intervention. We found that fractures about the talus required revision TAR surgery or arthrodesis.

LEVEL OF EVIDENCE

Level III, retrospective cohort study.

Outcomes of Total Ankle Arthroplasty in Moderate and Severe Valgus Deformity

Introduction. Failure to correct coronal deformity at the time of total ankle arthroplasty (TAA) can lead to early implant failure. We aimed to determine clinical, radiographic, and patient-reported outcomes of patients with moderate to severe valgus deformity who underwent TAA for end-stage ankle arthritis. Methods. Patients with a valgus deformity of at least 10° who underwent TAA were retrospectively reviewed. The coronal tibiotalar angle was assessed on radiographs preoperatively, at 1 year, and at final follow-up. The visual analog scale (VAS) for pain, Short Form-36 (SF-36), American Orthopaedic Foot and Ankle Society (AOFAS) hindfoot-ankle scale, and Short Musculoskeletal Function Assessment (SMFA) scores were assessed preoperatively and at final follow-up. Results. Mean preoperative valgus deformity was 15.5 ± 5.0°, and was corrected to a mean of 1.2 ± 2.6° of valgus postoperatively. VAS, SF-36, AOFAS, and SMFA scores improved significantly (P < .001 for all). There was no significant change in tibiotalar angle between 1 year and final follow-up in either group. Reoperation and revision rates did not differ between groups. Conclusion. Correction of coronal alignment was achieved and maintained in patients with both moderate and severe preoperative valgus malalignment. Outcome scores significantly improved for all patients. Levels of Evidence: Therapeutic, Level IV.

Revision Surgery for Metal Component Failure in Total Ankle Arthroplasty

Background:

Metal component failure in total ankle arthroplasty (TAA) is difficult to treat. Traditionally, conversion to an arthrodesis has been advocated. Revision TAA surgery has become more common with availability of revision implants and refinement of bone-conserving primary implants. The goal of this study was to analyze the clinical results and patient-reported outcomes for patients undergoing revision total ankle arthroplasty.

Methods:

We retrospectively reviewed prospectively collected data on 52 patients with a mean age of 63.5 ± 9.6 years who had developed loosening or collapse of major metal components following primary TAA. These patients were compared to a case-matched control group of 52 primary TAAs performed at the host institution with a minimum of 2 years’ follow-up. Cases of isolated polyethylene exchange, infection, or extra-articular realignment procedures were excluded. The American Orthopaedic Foot & Ankle Society (AOFAS) hindfoot score, Short Form 36 (SF-36), Short Musculoskeletal Function Assessment (SMFA), and pain scores were prospectively collected. Clinical data was collected through review of the electronic medical record to identify reasons for clinical failure, where clinical failure was defined as second revision or conversion to arthrodesis or amputation.

Results:

The identified causes of failure of primary TAA were aseptic loosening of both components (42%), talar component subsidence/loosening (36%), coronal talar subluxation (12%), tibial loosening (8%), and talar malrotation (2%). Thirty-one patients (59.5%) underwent revision of all components, 20 (38.5%) just the talar and polyethylene components, and one (2%) the tibial and polyethylene components. The average time to revision was 5.5 years ± 5.4 with a follow-up of 3.1 years ± 1.5 after revision. Eleven (21.2%) revision arthroplasties required further surgery: 6 required conversion to arthrodesis and 5 required second revision TAA. Pain scores, SF-36 scores, SMFA scores, and AOFAS Hindfoot scores all improved after revision surgery but never reached the same degree of improvement seen after primary TAA.

Conclusions:

Clinical and patient-reported outcomes of revision ankle arthroplasty after metal component failure significantly improved after surgery, although the recovery time was longer. In this series, 21.2% of revision TAAs required a second revision TAA or arthrodesis surgery. Various prostheses performed similarly when used for revision surgery. Revision TAA can offer significant improvements postoperatively.

Level of Evidence:

Level III, therapeutic.

Hindfoot Arthrodesis Screw Position and Trajectory Effect on Talus Subsidence When Performed With Total Ankle Arthroplasty

BACKGROUND:

Total ankle arthroplasty (TAA) is increasingly being recognized as an effective surgical option for end-stage ankle arthritis. Associated hindfoot arthrodesis procedures are at times needed to correct malalignment or to address adjacent joint arthritis. Results following TAA and associated hindfoot arthrodesis have at times been underwhelming and the devascularization of the talar blood supply has been postulated as a potential cause. This study explored the association between hindfoot arthrodesis fixation and talar component subsidence.

METHODS:

The study included 81 consecutive patients who underwent a TAA with either an isolated subtalar arthrodesis or combined subtalar and talonavicular arthrodesis with a minimum of 2 years of follow-up. Radiographic and clinical evaluations including patient-reported outcomes were performed at each postoperative visit. The primary outcome measure was the presence of talar component subsidence while patient-reported outcomes were the secondary outcome measure.

RESULTS:

30.9% of patients had evidence of talar component subsidence. Subsidence was seen in 55.5% of patients with dorsal to plantar subtalar fixation compared to 11.1% of patients with plantar to dorsal screws ( P < .001) and in 44.4% of patients with screws violating the sinus tarsi compared to 3.7% of patients without screws in the sinus tarsi ( P < .001). Screws that were placed from dorsal to plantar were more likely to violate the sinus tarsi ( P < .001). Patients with evidence of talar subsidence reported higher pain scores and lower functional scores. There were 8 TAA failures, and the presence of dorsal to plantar screws was associated with failure ( P < .01).

CONCLUSION:

Screws that are placed across the subtalar joint from a dorsal to plantar approach are more likely to violate the sinus tarsi, contributing to a significantly higher rate of talar component subsidence when associated with TAA.

LEVEL OF EVIDENCE:

Level II, prospective comparative series.

The Effect of Patient Characteristics on 1 to 2-Year and Minimum 5-Year Outcomes After Total Ankle Arthroplasty

BACKGROUND

Total ankle arthroplasty has shown durable improvements in patient-reported outcomes. However, the impact of common comorbidities and patient factors has not been fully characterized. The purpose of this study was to identify patient comorbidities and characteristics that impact outcomes after total ankle arthroplasty.

METHODS

Patients who underwent a total ankle arthroplasty between January 2007 and December 2016 were enrolled into a prospective study at a single academic center. Patients completed outcome measures before the surgical procedure and at the time of follow-up: a visual analog scale (VAS) for pain, the 36-item Short Form Survey (SF-36), and the Short Musculoskeletal Function Assessment (SMFA). Patient and operative factors, along with prevalent preoperative comorbidities, were analyzed for association with preoperative to postoperative changes in 1 to 2-year and minimum 5-year outcomes. Comorbidities that met a significance threshold of p < 0.05 in adjusted analyses were incorporated into multivariable outcome models.

RESULTS

A total of 668 patients with a mean 1 to 2-year follow-up (and standard deviation) of 1.6 ± 0.5 years (range, 10 months to 2 years and 2 months) were included. Patients' pain and function significantly improved across all outcomes (p < 0.05). However, depression, staged bilateral ankle arthroplasty, increased length of stay, a prior surgical procedure, increased American Society of Anesthesiologists (ASA) score, and particular implant types were associated with significantly smaller improvements in at least 1 patient-reported outcome after total ankle arthroplasty in the 1 to 2-year follow-up, although the effects were relatively small. At a minimum 5-year follow-up, smoking, depression, implant type, and staged bilateral ankle arthroplasty were associated with worse outcomes, and a prior surgical procedure, a simultaneous bilateral surgical procedure, and obesity were associated with improved outcomes.

CONCLUSIONS

Patients who underwent total ankle arthroplasty had significant improvement in patient-reported outcomes, although several factors were associated with a small, but significant, negative impact on improvement, including depression, increased ASA score, current smoking, increased length of stay, a prior surgical procedure, and staged bilateral total ankle arthroplasty. Current smoking, obesity, and depression are potentially modifiable risk factors that could be improved prior to total ankle arthroplasty. Patients with these characteristics should be counseled on their risk of limited improvement in ankle pain and disability after total ankle arthroplasty.

LEVEL OF EVIDENCE

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

Possible Implications for Bundled Payment Models of Comorbidities and Complications as Drivers of Cost in Total Ankle Arthroplasty

BACKGROUND:

The Comprehensive Care for Joint Replacement (CJR) model provides bundled payments for in-hospital and 90-day postdischarge care of patients undergoing total ankle arthroplasty (TAA). Defining patient factors associated with increased costs during TAA could help identify modifiable preoperative patient factors that could be addressed prior to the patient entering the bundle, as well as determine targets for cost reduction in postoperative care.

METHODS:

This study is part of an institutional review board-approved single-center observational study of patients undergoing TAA from January 1, 2012, to December 15, 2016. Patients were included if they met CJR criteria for inclusion into the bundled payment model. All Medicare payments beginning at the index procedure through 90 days postoperatively were identified. Patient, operative, and postoperative characteristics were associated with costs in adjusted, multivariable analyses. One hundred thirty-seven patients met inclusion criteria for the study.

RESULTS:

Cerebrovascular disease (intracranial hemorrhages, strokes, or transient ischemic attacks) was initially associated with increased costs (mean, $5595.25; 95% CI, $1710.22-$9480.28) in adjusted analyses ( P = .005), though this variable did not meet a significance threshold adjusted for multiple comparisons. Increased length of stay, discharge to a skilled nursing facility (SNF), admissions, emergency department (ED) visits, and wound complications were significant postoperative drivers of payment.

CONCLUSION:

Common comorbidities did not reliably predict increased costs. Increased length of stay, discharge to an SNF, readmission, ED visits, and wound complications were postoperative factors that considerably increased costs. Lastly, reducing the rates of SNF placement, readmission, ED visitation, and wound complications are targets for reducing costs for patients undergoing TAA.

LEVEL OF EVIDENCE:

Level II, prognostic prospective cohort study.