Risk Factors for Nonunion Following Ankle Arthrodesis: A Systematic Review and Meta-analysis

Reaming for Tibiotalocalcaneal Nailing Removes Only 10% of the Ankle and Subtalar Joints

OBJECTIVES

Tibiotalocalcaneal (TTC) nailing in the setting of acute ankle trauma has become increasingly popular. No consensus exists as to whether formal joint preparation is necessary, although there is some concern that residual motion at unprepared joints may lead to implant loosening and/or breakage. The objective of this study was to quantify the proportion of tibiotalar and subtalar articular surface destruction that occurs during reaming for TTC nail fixation.

METHODS

Twelve cadaver lower extremities were procured. The specimens were pinned into neutral ankle and hindfoot alignment. A guidewire was inserted under fluoroscopy, followed by a 12-mm opening reamer. The specimens were then dissected, exposing the tibial plafond, talar dome, posterior facet of the talus, and posterior facet of the calcaneus. Images of each joint were obtained, and ImageJ software was used to calculate the total joint surface area and the area of articular destruction.

RESULTS

The mean proportion of articular cartilage destruction was 9.3%, 10.3%, 8.9%, and 10.3% for the tibial plafond, talar dome, posterior facets of the talus, and posterior facets of the calcaneus, respectively. No joint destruction was observed in the middle facets of the subtalar joint.

CONCLUSIONS

Reaming for TTC nail placement violates approximately 10% of each articular surface of the tibiotalar and subtalar joints. Retention of 90% of the articular surface may allow for residual motion at the joints and therefore potentially substantial stress on the implant. Formal joint preparation for the purposes of achieving fusion during TTC nail placement may be beneficial to prevent implant loosening or breakage.

Association of Smokeless Tobacco and Complications Following Ankle and Hindfoot Arthrodesis

BACKGROUND

The purpose of this study was to (1) evaluate the rates of postoperative complications following ankle or hindfoot arthrodesis among current smokeless tobacco users and people who smoke compared to matched controls, and (2) compare rates of postoperative complications in current smokeless tobacco users vs people who smoke tobacco cigarettes.

METHODS

A retrospective cohort study was conducted using a large national database. For patients who underwent ankle or hindfoot arthrodesis, smokeless tobacco users (n = 131) and people who smoke (n = 1948) were matched 1:4 with controls, and smokeless tobacco users (n = 131) were matched 1:4 with people who smoke tobacco cigarettes (n = 524). Orthopaedic complications within 90 days, 1 year, and 2 years were compared using multivariable logistic regressions.

RESULTS

Within 90 days of ankle or hindfoot arthrodesis, smokeless tobacco users demonstrated significantly higher rates of hardware removal (odds ratio [OR] 5.01, 95% CI 1.65-15.20), wound disruption or dehiscence (OR 3.00, 95% CI 1.21-7.44), and pooled complications (16.0% vs 5.9%, OR 2.84, 95% CI 1.50-5.38) compared with tobacco-naïve controls. The rates of hardware removal, wound disruption and dehiscence, and pooled complications remained significant in the smokeless tobacco cohort at 1 and 2 years. At 2 years following ankle or hindfoot arthrodesis, smokeless tobacco users additionally demonstrated significantly higher rates of infection (OR 6.08, 95% CI 1.15-32.05) and nonunion (OR 2.35, 95% CI 1.31-4.20) compared with tobacco-naïve controls. Within 90 days of ankle or hindfoot arthrodesis, smokeless tobacco users demonstrated significantly lower rates of malunion or nonunion than patients who smoke tobacco cigarettes (OR 0.34, 95% CI 0.12-0.97), whereas all other complications were not significantly different.

CONCLUSION

Smokeless tobacco use is associated with higher rates of complications following ankle or hindfoot arthrodesis compared with tobacco-naïve controls, and physicians should screen for smokeless tobacco use specifically and encourage cessation before operating electively.

LEVEL OF EVIDENCE

Level III, retrospective cohort study.

Evaluating Failure Mechanisms for Total Talus Replacement: Contemporary Review

BACKGROUND

As total talus replacement (TTR) grows in popularity as a salvage option for talar collapse, a critical evaluation of the complications associated with this procedure is indicated.

METHODS

In this review of the literature, we present a patient report and provide a review of several complications seen after TTR, including ligamentous instability, infection, and adjacent joint osteoarthritis, which we have encountered in our practice.

RESULTS

Total talus replacement has the potential to reduce pain and preserve range of motion. However, the treating surgeon must be cognizant of the variety of adverse outcomes. We have presented cases of potential devastating complications from our own clinical experience and the literature.

CONCLUSIONS

In conclusion, TTR may have utility in the properly selected patient with end-stage talar collapse, but implant composition, indications, and patient demographic variables complicate the interpretation of the literature.Levels of Evidence: Level III.

Patient-related risk factors associated with poorer outcomes following total ankle arthroplasty

Aims

This scoping review aims to identify patient-related factors associated with a poorer outcome following total ankle arthroplasty (TAA).

Methods

A scoping review was performed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. A computer-based literature search was performed in PubMed, Embase, Cochrane trials, and Web of Science. Two reviewers independently performed title/abstract and full-text screening according to predetermined selection criteria. English-language original research studies reporting patient-related factors associated with a poorer outcome following TAA were included. Outcomes were defined as patient-reported outcome measures (PROMs), perioperative complications, and failure.

Results

A total of 94 studies reporting 101,552 cases of TAA in 101,177 patients were included. The most common patient-related risk factor associated with poorer outcomes were younger age (21 studies), rheumatoid arthritis (17 studies), and diabetes (16 studies). Of the studies using multivariable regression specifically, the most frequently described risk factors were younger age (12 studies), rheumatoid arthritis (eight studies), diabetes (eight studies), and high BMI (eight studies).

Conclusion

When controlling for confounding factors, the most commonly reported risk factors for poor outcome are younger age, rheumatoid arthritis, and comorbidities such as diabetes and increased BMI. These patient-related risk factors reported may be used to facilitate the refinement of patient selection criteria for TAA and inform patient expectations.

The Fate of Delayed Unions After Isolated Ankle Fusion

BACKGROUND

Nonunion remains the most common major complication of ankle arthrodesis. Although previous studies have reported delayed union or nonunion rates, few have elaborated on the clinical course of patients experiencing delayed union. In this retrospective cohort study, we sought to understand the trajectory of patients with delayed union by determining the rate of clinical success and failure and whether the extent of fusion on computed tomography scan (CT) was associated with outcomes.

METHODS

Delayed union was defined as incomplete (<75%) fusion on CT between 2 and 6 months postoperatively. Thirty-six patients met the inclusion criterion: isolated tibiotalar arthrodesis with delayed union. Patient-reported outcomes were obtained including patient satisfaction with their fusion. Success was defined as patients who were not revised and reported satisfaction. Failure was defined as patients who required revision or reported being not satisfied. Fusion was assessed by measuring the percentage of osseous bridging across the joint on CT. The extent of fusion was categorized as absent (0%-24%), minimal (25%-49%), or moderate (50%-74%).

RESULTS

We determined the clinical outcome of 28 (78%) patients with mean follow-up of 5.6 years (range, 1.3-10.2). The majority (71%) of patients failed. On average, CT scans were obtained 4 months after attempted ankle fusion. Patients with minimal or moderate fusion were more likely to succeed clinically than those with "absent" fusion (P = .040). Of those with absent fusion, 11 of 12 (92%) failed. In patients with minimal or moderate fusion, 9 of 16 (56%) failed.

CONCLUSION

We found that 71% of patients with a delayed union at roughly 4 months after ankle fusion required revision or were not satisfied. Patients with less than 25% fusion on CT had an even lower rate of clinical success. These findings may help surgeons in counseling and managing patients experiencing a delayed union after ankle fusion.

LEVEL OF EVIDENCE

Level IV, retrospective cohort study.

Association of Preexisting Triple Fusion and Arthroscopic Ankle Arthrodesis nonunion

BACKGROUND

Arthroscopic ankle arthrodesis (AAA) is a successful treatment for end-stage ankle arthritis. A significant early complication of AAA is symptomatic nonunion. Published nonunion rates range from 8% to 13%. Longer term, there is concern that it predisposes to subtalar joint (STJ) fusion. To better understand these risks, we undertook a retrospective investigation of primary AAA.

METHODS

All adult AAA cases conducted at our institution over a 10-year period were reviewed. A total of 284 eligible AAA cases in 271 patients were analyzed. The primary outcome measure was radiographic union. Secondary outcome measures included reoperative rate, postoperative complications and subsequent STJ fusion. Univariate and multivariate logistic regression analysis was performed to identify nonunion risk factors.

RESULTS

The overall nonunion rate was 7.7%. Smoking (odds ratio [OR] 4.76 [1.67, 13.6], P = .004) and previous triple fusion (OR 40.29 [9.46, 171.62], P < .001) were independent risk factors on univariate analysis. Only prior triple fusion persisted as a major risk factor associated with nonunion on multivariate analysis (OR 18.3 [3.4, 99.7], P < .001). Seventy percent of patients with a previous triple fusion went on to develop nonunion compared to 5.5% of those without. Increasing age, obesity, surgical grade, diabetes, postoperative weightbearing plan, steroid use, and inflammatory arthropathy were not significant risk factors. The leading cause of reoperation was hardware removal (18%). There were 5 superficial (1.8%) and 4 deep (1.4%) infections. Eleven (4.2%) required subsequent STJ fusion. The "survivorship" of STJ post AAA was 98%, 85%, and 74% at 2, 5, and 9 years, respectively.

CONCLUSION

As the largest study of AAA in the literature, our findings suggest prior triple fusion is a major independent risk factor for AAA nonunion. These patients should be counseled of this high risk and may benefit from alternative surgical options.

LEVEL OF EVIDENCE

Level III, retrospective cohort study.

The Trans-Achilles Approach for Plate Supplementation of Ankle Arthrodesis With an Existing Hindfoot Fusion Nail: A Case Report

Tibiotalar arthrodesis revision surgeries are not uncommon. Several approaches have been described in the literature for ankle arthrodesis nonunions. In this article, we describe the posterior trans-Achilles approach, which ensures adequate surgical exposure while minimizing damage to the surrounding soft tissues. It provides a convenient method for utilizing bone grafts or substitutes and allows for the advantageous application of posterior plating. The possible complications of this approach are delayed wound healing, wound infection, injury to the sural nerve, and the potential need for a skin graft. Despite the advantages of this approach, infection, delayed union, and nonunion risks remain high in this patient population. Finally, the trans-Achilles approach is valid for complex ankle procedures, especially in revisions with compromised ankle soft tissue envelopes.

Factors Associated With Poor Patient-Reported Outcomes in Isolated Gastrocnemius Recession for Heel Pain

Background

Gastrocnemius recession is commonly performed for a variety of pathologies of the foot and ankle, yet studies characterizing risk factors associated with patient-reported outcomes are limited. In this cohort study, patient outcomes were compared against the general population for PROMIS scores with correlation analysis comparing demographics and comorbidities. Our primary goal in this study is to identify risk factors associated with poor patient-reported outcomes following isolated gastrocnemius recession for patients with plantar fasciitis or insertional Achilles tendinopathy.

Methods

A total of 189 patients met inclusion criteria. The open Strayer method was preferred. However, if the myotendinous junction could not be adequately visualized without expanding the excision, then a Baumann procedure was performed. The decision between the two did not depend on preoperative contracture. Patient demographics and visual analog scale (VAS) scores were obtained via the electronic medical record. Telephone interviews were completed to collect postoperative Patient-Reported Outcomes Measurement Information System (PROMIS) and Foot Function Index (FFI) scores. The data were analyzed using the type 3 SS analysis of variance test to identify individual patient factors associated with reduced PROMIS, FFI, and VAS scores.

Results

No demographic variables were found to be significantly associated with postoperative complications. Patients who reported tobacco use at the time of surgery had significantly decreased postoperative PROMIS physical function (P = .01), PROMIS pain interference (P < .05), total FFI scores (P < .0001), and each individual FFI component score. Patients undergoing their first foot and ankle surgeries reported numerous significant postoperative outcomes, including decreased PROMIS pain interference (P = .03), higher PROMIS depression (P = .04), and lower FFI pain scores (P = .04). Hypertension was significantly associated with an increased FFI disability score (P = .03) and, along with body mass index (BMI) >30 (P < .05) and peripheral neuropathy (P = .03), significantly higher FFI activity limitation scores (P = .01). Pre- and postoperative VAS scores demonstrated improvement in patient-reported pain from a mean of 5.53 to 2.11, respectively (P < .001).

Conclusion

We found in this cohort that numerous patient factors were independently associated with differences in patient-reported outcomes following a Strayer gastrocnemius recession performed for plantar fasciitis or insertional Achilles tendinopathy. These factors include, but are not limited to, tobacco use, prior foot and ankle surgeries, and BMI. This study strengthens previous reports demonstrating the efficacy of isolated gastrocnemius recession and elucidates variables that may affect patient-reported outcomes.

Level of Evidence

Level III, retrospective cohort study.

Sex-Based Difference in Bone Healing: A Review of Recent Pre-clinical Literature

PURPOSE OF REVIEW

Recent literature has sought to understand differences in fusion failure, specifically considering how patient sex may play a role. Overall, there exists inconclusive data regarding any sex-based differences in bone healing.

RECENT FINDINGS

In vitro studies examining the roles of sex hormones, 5-LO, IGF-1, VEGF, osteoclasts, and OPCs seem to show sexually dimorphic actions. Additionally, donor characteristics and stem cell environment seem to also determine osteogenic potential. Building on this biomolecular basis, in vivo work investigates the aforementioned elements. Broadly, males tend to have a more robust healing compared to females. Taking these findings together, differences in sex hormones levels, their timing and action, and composition of the inflammatory milieu underlie variations in bone healing by sex. Clinically, a robust understanding of bone healing mechanics can inform care of the transgender patient. Transgender patients undergoing hormone therapy present a clinically nuanced scenario for which limited long-term data exist. Such advances would help inform treatment for sports-related injury due to hormonal changes in biomechanics and treatment of transgender youth. While recent advances provide more clarity, conclusive answers remain elusive.

Does Concurrent Distal Tibiofibular Joint Arthrodesis Affect the Nonunion and Complication Rates of Tibiotalar Arthrodesis?

Tibiotalar arthrodesis successfully treats ankle arthritis but carries risk of nonunion. It is unclear whether concurrent distal tibiofibular arthrodesis affects tibiotalar nonunion rate. The purpose of this study is to compare tibiotalar nonunion and complication rates in patients with versus without a distal tibiofibular arthrodesis. This is a retrospective review of 516 consecutive ankle arthrodesis performed between March 2002 and May 2016. A total of 319 ankles (312 patients) underwent primary, open tibiotalar arthrodesis (227 with distal tibiofibular arthrodesis, 92 without). Primary outcome measure was nonunion rate. Secondary outcome measures were time to tibiotalar union, rate of development of post-operative deep vein thrombosis (DVT)/pulmonary embolism (PE), rate of deep wound complications, and rate of return to operating room (OR). No differences in nonunion rates were observed in both cohorts of patients with versus without distal tibiofibular arthrodesis: 17/227 (7.5%) versus 11/92 (12%) (p = 0.2), respectively, odds ratio was 0.74, 95% CI: 0.29~2.08 (p = 0.55). There was no difference in deep wound complications (5.3% versus 10.9%, p = 0.42), time to union (3.7 months versus 4.1 months, p = 0.72), or rate of development of DVT/PE (5.2% versus 2.2%, p = 0.18) between patients with and without distal tibiofibular arthrodesis, respectively. This is the first study directly comparing nonunion and complication rates in primary, open ankle arthrodesis with and without distal tibiofibular arthrodesis. Inclusion of the distal fibular joint with the tibiotalar fusion was not associated with a change in tibiotalar nonunion rate, time to union, wound complications, or postoperative DVT/PE.

Patient and Surgical Factors Affecting Fusion Rates After Arthroscopic and Open Ankle Fusion: A Review of a High-Risk Cohort

ABSTRACT

We present a case series with the objective of identifying risk factors for nonunion after open and arthroscopic primary ankle arthrodesis. Eighty-seven patients who underwent primary ankle arthrodesis and met inclusion criteria were divided into open (N = 46) and arthroscopic (N = 41) groups. Patient and operative characteristics were retrospectively analyzed as possible risk factors for nonunion within each technique. The nonunion rate was 11% in the open and 12% in the arthroscopic group. Obesity, smoking, and ASA class 3 were highly prevalent in both groups. In the arthroscopic group, a remote history of infection and the use of headed screws had notably higher risk of nonunion, though not statistically significant. In the open group, use of bone graft trended toward lower risk of nonunion, though also not statistically significant. The results of this study demonstrated, nonunion rates are comparable between open and arthroscopic ankle arthrodesis in high-risk patients. For patients with a remote history of infection, open ankle arthrodesis may be preferable, and bone graft importance may vary with open versus arthroscopic technique.

LEVEL OF EVIDENCE

III.

Factors Associated With Nonunion and Infection Following Ankle Arthrodesis Using a Large Claims Database: Who Has Elevated Risk?

Background:

Complications such as nonunion and infection following ankle arthrodesis can lead to increased patient morbidity and financial burden from repeat operations. Improved knowledge of risk factors can improve patient selection and inform post–ankle arthrodesis surveillance protocols.

Methods:

This is a large retrospective, database study with structured query of a national insurance claims database (PearlDiver Technologies) for patients treated with ankle arthrodesis from 2015 to 2019 as identified by International Classification of Diseases, Tenth Revision (ICD-10), codes. Patients with any operation 1 year prior to or following ankle arthrodesis were excluded from analysis to prevent attributing complications to another operation. Likelihoods of nonunion and infection within 1 year and 3 years following ankle arthrodesis were analyzed using Kaplan-Meier estimations. Patient characteristics associated with the identified complications following ankle arthrodesis were analyzed using multivariable logistic regression analyses.

Results:

Our query yielded 2463 patients in the 5-year period who underwent ankle arthrodesis. Nonunion occurred in 11% (95% CI 10-12) of patients within 1 year of ankle arthrodesis and 16% (95% CI 14-17) of patients within 3 years. Infection occurred in 3.9% (95% CI 3.1-4.7) of patients within 1 year of ankle arthrodesis and in 6.2% (95% CI 5.1-7.2) of patients within 3 years. Obese patients increased odds of nonunion on multivariable analysis (OR 1.6, 95% CI 1.3-2.0; P < .001). On multivariable analysis, diabetes (OR 1.7, 95% CI 1.2-2.6; P = .010) and each 1-unit increase in Elixhauser Comorbidity Index scores (OR 1.1, 95% CI 1.1-1.2; P < .001) contributed to increased odds of infection after ankle arthrodesis.

Conclusion:

Nonunion and infection following ankle arthrodesis have a 3-year probability of 16% and 6%, respectively. More than one-quarter of patients with nonunion following ankle arthrodesis experience a delay in diagnosis beyond 1 year. The risk of post–ankle arthrodesis nonunion is highest in patients with obesity; the risk of post–ankle arthrodesis infection is highest in patients with diabetes or an elevated Elixhauser Comorbidity Index score.

Level of Evidence:

Level III, prognostic study.