Perspectives on Ligament Augmentation Techniques Among AOFAS Members: A Cross-Sectional Survey

Authors: Nathaniel E. Zona, Samuel D. Stark, Alexander Vlasak, Sergei O. Alexeev, Kenneth J. Hunt

Abstract

Background:

Ligamentous pathologies and injuries of the foot and ankle commonly require surgical repair. Ligament augmentation techniques (LAT) use a synthetic ligament that spans the anatomic length of the injured ligament, anchoring to bone on both ends. Use of LAT in foot and ankle surgery is rapidly progressing, but the rates of usage and surgeon-specific indications are not well known. This study aims to provide an in-depth analysis of LAT use by foot and ankle surgeons.

Methods:

An online survey was distributed to the surgeon members of the American Orthopaedic Foot & Ankle Society (AOFAS). Survey questions detailed demographics and practice details, current use of LATs, and the future trajectory of LATs. Responses were tabulated and summarized. Logistic regression and χ2 tests of independence compared trends in LAT use between North America and outside continent, years in practice, and type of practice.

Results:

Of 1895 invited surgeons, 244 (12.9%) completed the survey. Among respondents, 209 surgeons (85.7%) reported current LAT use, most of whom were based in North America (197, 80.7%). North American respondents were significantly more likely to report using LAT when compared to respondents outside of North America (89% vs 72% respectively) (P = .007). The 3 most common ligaments for LAT use were the ATFL (205, 98.1%) followed by the syndesmosis ligament (125, 59.8%) and the deltoid ligament (122, 58.4%). The most common reason for LAT use was faster return to sport (136, 65.1%). More than half of respondents (131, 53.6%) anticipate increased LAT in the future.

Conclusion:

LAT use in foot and ankle surgery is multifactorial, influenced by patient demographics, regional practices, industry dynamics, and surgeon training. Ongoing debates about the cost-effectiveness and long-term outcomes of LAT suggest that further research is necessary to fully define its role in orthopaedic foot and ankle surgery.

Level of Evidence:

Level V, therapeutic.

Introduction

Ligamentous injuries and ligament pathology of the foot and ankle are common and at times require surgical repair of the ruptured or attenuated tissues. These repairs can result in prolonged recovery times and delayed return to activity. Ligament augmentation techniques (LAT) have recently been introduced in foot and ankle surgery, attempting to reduce recovery time and improve immediate postoperative stability.^ 2 ^ LAT can broadly be described as a synthetic, flexible material that spans the anatomical ligament and is anchored to bone on both ends. LAT was first attempted more than a century ago for repair of the anterior cruciate ligament,^ 9 ^ but the modern LAT began in the late 20th century with the use of devices like the Ligament Advanced Reinforcement System and the Kennedy Ligament Augmentation Device.^19,33,41^

LAT was introduced to foot and ankle surgery in the early 2000s for repair of the tibiofibular syndesmosis, using a suture-button construct.^56,57^ Since then, LATs have been expanded to several other ligamentous structures including the anterior talofibular ligament (ATFL),^10,12,15,16,36,49,50,59,61,64^ the deltoid ligament,^7,14,46^ the Lisfranc ligaments,^13,18,32,42,44^ the spring ligament,^1,4,24,30,45,54^ the calcaneofibular ligament (CFL),^25,29,58^ and the collateral ligaments of the hallux.^11,22,40^ A recent review found that despite there being no publications regarding LAT for the foot and ankle prior to 2005, foot and ankle now accounts for 28.9% of such publications.^ 2 ^ A survey of ISAKOS surgeons in 2023 found that 87% of fellowship-trained foot and ankle surgeons use LAT. This represented the highest percentage of LAT use among the represented specialties.^ 31 ^ These studies depict a rapid rise in both the anatomical locations, and the rate of LAT use in foot and ankle surgery.

Although LAT usage is increasing in foot and ankle surgery, the surgeon-specific rationale for its application remains poorly defined. The goal of this study was to identify the influential factors that contribute to foot and ankle surgical decision making regarding LAT use among the AOFAS membership.

Methods

Following exemption from our institutional review board, a voluntary survey was sent to the active (n = 1,265), candidate (n = 137), and international (n = 493) surgeon members of the American Orthopaedic Foot & Ankle Society (AOFAS) via email. All anonymous responses were collected between February 6, 2024, and April 5, 2024, using REDCap electronic data capture tools. There was no incentive for participating in the survey.

The survey was composed of 3 sections, including demographics and practice details, current use of LAT, and the future trajectory of LAT. Sections 1 and 3 were asked to all respondents, whereas section 2 was limited to those using LAT in their practice. Branching logic was used to reduce survey fatigue, only asking participants questions relevant to the prior response. There was a maximum of 61 questions. The survey was designed to take an average of 15 minutes to complete and can be viewed in the Supplemental Information.

Data analysis was performed using the R statistical package (V4.2.1). Survey responses were summarized as frequencies and proportions. In the second section of the survey, subgroup analyses were performed by type of practice (academic, community hospital, and private), years in practice, and practice location (North America vs other continents). χ^2^ tests of independence were used to identify associations between current LAT use and the type of practice or practice location. Given a low sample size for non–North American respondents, we calculated a post hoc fragility index (FI) for significant differences found between practice locations. The FI is a way to determine how robust or fragile a significant finding of a dichotomous outcome is by identifying the minimum number of respondents who would need to flip their binary response to reverse the significance of a result using a Fisher exact test.^ 20 ^ A lower FI indicates greater fragility of a result. Logistic regression models assessed associations between current LAT use and years in practice. A P value of <.05 was considered statistically significant in all tests.

Results

Our survey of the AOFAS candidate, active, and international membership was initiated by 249 foot and ankle surgeons, corresponding to 13.1% of the surveyed membership. Of these respondents, 244 (98.0%) completed the required survey fields and were included in our analysis. North America was the most common location of practice, with 197 (80.7%) respondents. In total, 212 (86.9%) respondents had a practice composed of 75% to 100% foot and ankle surgery. All respondent demographics and practice details can be found in Table 1.

Use of LAT

LAT was used by 209 (85.7%) surgeons. Among North American surgeons, 88.9% use LAT (Figure 1A). No geographic region of the United States notably deviates from the whole cohort’s rate of LAT use, and the rates were not significantly different from each other (P = .436) (Figure 1B). There was a significant difference (P = .007) between North American respondents (89% yes) and surgeons from all other continents (72% yes). However, the FI was 3, indicating that if 3 non–North American surgeons reported “yes” instead of “no” for their use of LAT, no significant difference would be observed. No significant difference was observed between rates of LAT use and practice type nor was a significant association found between rates of LAT use and years in practice (Tables S1 to S3).

Anatomical Location

Many surgeons report the ATFL as a common location for use, although very few surgeons will use LAT on the PTFL (Table 2). There were 39 surgeons who noted other locations, including the spring ligament (n = 24), CFL (n = 12), Lisfranc ligaments (n = 3), and AITFL (n = 1). The 3 most common ligaments that surgeons perform LAT—the ATFL, syndesmosis ligament, and deltoid ligament—displayed a bimodal distribution in the proportion of repairs done with LAT (Figure 2). Although the median percentage of repairs done with LAT for these respective ligaments was 50%, 75.5%, and 49%, a high concentration of surgeons for each ligament reported using LAT far more or far less than the median. For each of these respective ligaments, there was a statistically significant correlation between the percentage of repairs being performed with LAT and the volume of LAT repairs done within the last 2 years (P < .001 for each ligament).

Motivation for Learning LATs and Reasons Surgeons Use LATs

The reported primary motivation to learn LAT, with 134 (64.1%) respondents, was an individual interest in the skill. This was followed by 56 (26.8%) having LAT skills required in their residency or fellowship training, 13 (6.2%) had unique motivations, 5 (2.4%) did not have a motivation, and 1 (0.5%) was motivated by a patient request. More than 90% of surgeons reported a belief in faster return to sport and better outcomes compared with non-LAT repair as reasons for performing LAT (Figure 3). The reasons for use were not statistically different between North America vs other continents and not significantly associated to years in practice (Tables S1 and S3). More academic surgeons reported a desire to use their training than those in community hospitals or private practice (P = .046) but otherwise there were no statistically significant differences (Table S2).

Influential Factors for Using LATs

The most reported influential factor for use of LAT was elite athlete status (Figure 4). All the listed patient characteristics generally influenced an increased use of LAT. Only 14 respondents stated no patient characteristics influencing their use. Respective influential factors were not statistically different between practice type and not significantly associated to years in practice (Tables S2 and S3). Elite athlete status was recognized at significantly greater rates among North American respondents (60% vs 43%; P = .029), as was manual labor (43% vs 26%; P = .031) (Table S1).

Concerns About Cost

There is a wide distribution of concern in the cost of LAT use (Figure 5). The varying levels of concern were not significantly different nor associated with any of the practice characteristic subgroups. Although concerns about cost did not significantly differ by type of practice, 44.1% of private practice surgeons reported being concerned, whereas only 37.9% and 31.3% of academic and community hospital surgeons reported concerns (Table S2).

Future Trajectory of LATs

More than half of the 244 respondents (131, 53.6%) believe LATs will be used more 5 years in the future, whereas only 9 (3.7%) surgeons estimate that their use will decrease and 84 (34.4%) anticipate using LAT about the same. The remaining 16 (6.6%) respondents expressed uncertainty about their future use. The leading reason for increased, similar, and decreased trajectory of LAT is an expected increase in evidence, absence of new evidence, and a lack of supportive evidence for LATs over traditional techniques, respectively (Figure 6). Despite this controversy, the number of individuals who believe future evidence will support LAT is 16 times greater than those who believe it will not.

Discussion

This survey of the AOFAS provides a comprehensive analysis of current practices regarding ligament augmentation techniques (LAT) in foot and ankle surgery, based on responses from 244 surgeons. This study offers critical insights into the adoption and future trajectory of LAT. The results indicate differences in LAT adoption attributable to anatomic differences and similarities among the drivers of surgical decision making, highlighting the importance of resource availability and questioning the impact of emerging technologies.

LAT Utilization Across Anatomical Locations

Of the 209 AOFAS surgeons who use LAT in their practice, 98.1% report using LAT for ATFL repairs. However, they apply this technique in a median of 50% of their ATFL cases, indicating that although LAT is widely considered as a potential tool for enhancing biomechanical stability, it is not universally applied to all ATFL repairs. This suggests that surgeons are selective in their use of LAT, reserving it for cases where they believe it offers the most benefit. It may not be appropriate in every case. Nonetheless, the high adoption rate aligns with recent literature demonstrating the effectiveness of suture tape augmentation in Boström repairs, resulting in low rates of recurrent ankle instability even in cases with poor ligamentous tissue quality.^ 35 ^ However, other studies cast doubt on superiority of LAT use, showing that Boström repairs with suture tape resulted in similar patient-reported outcomes as Boström repair alone.^ 16 ^ Even so, ATFL repairs are by far the most prevalent use of LATs in the foot and ankle.^ 31 ^

Our results indicate that 59.8% of surgeons use LAT, including suspension techniques such as suture buttons and direct augmentation with suture anchors, for syndesmosis ligament repairs. This usage suggests surgeons are recognizing the limitations of traditional static fixation methods. A growing body of recent literature supports several advantages of LAT-based repair of the syndesmosis over solid fixation. These include better functional outcomes,^3,35,62^ lower rates of removal and implant failure,^52,62^ lower risk of syndesmotic malreduction,^38,65^ and improved biomechanical properties and long-term joint stability.^34,38^

Deltoid ligament repairs show an adoption rate at 58.4%. This variability reflects debates about the necessity of complex and costly augmentation in deltoid repairs, where traditional suture techniques may suffice. Having a patient who is an elite athlete or a manual laborer were among the 2 most reported patient factors that would indicate the use of LAT. These findings are consistent with recent literature demonstrating both the biomechanical efficacy^7,8^ and improved clinical outcomes with LAT of the deltoid.^46,60^ We speculate that some surgeons prefer nonaugmented approaches in lower-demand patients or with lower severity injuries deemed manageable without augmentation.

Notably, the data show lower adoption of LAT in hallux ligaments (11.5%). This may be due to several factors. First, our results demonstrate a lower volume of hallux ligament surgeries being performed when compared to those above. Despite reports of good outcomes for bunion correction with LAT techniques,^ 48 ^ this practice has not significantly expanded. This may be a reflection of the relatively underreported nature of hallux ligamentous injuries in the literature, including plantar plate and collateral ligament injuries.^28,51^ In addition, limited evidence-based treatment guidelines exist for the treatment of hallux ligamentous injuries, and many outcomes studies cover small numbers of high-level athletes, limiting the utility of these works across the broader population.^23,55^

Overall high reported LAT usage in ATFL and syndesmosis repairs suggests a moderate consensus on the benefits of augmentation in these frequently injured areas among the sampled AOFAS surgeons. However, the more modest adoption in deltoid repairs and minimal use in hallux ligaments may indicate areas of lower overall clinical volume (when compared to ATFL and syndesmosis repairs) and perhaps where further research and clinical experience are needed to establish best practices. Our findings are consistent with the broader trend of increasing LAT use in orthopaedic surgery, with a recent study showing that 60.4% of LAT literature has been published since 2017.^ 2 ^

Industries’ Impact on LAT

The rapid adoption of LAT in foot and ankle surgery is frequently justified by purported benefits such as accelerated rehabilitation and quicker return to sport. However, our findings raise questions about the foundation of these claims, as we did not ascertain whether this rationale stems from robust clinical evidence, individual provider experience, or information disseminated through educational platforms—many of which may be influenced by industry interests rather than independent, peer-reviewed data. This lack of clarity is particularly concerning given the expanding commercial footprint of device manufacturers in orthopaedic surgery, where industry marketing and direct-to-provider education have demonstrably shaped surgical practice patterns and decision making.^ 6 ^

Notably, 12% of surveyed surgeons reported LAT use in response to patient requests, a figure that, although seemingly minor, suggests that patient demand (possibly fueled by direct-to-consumer advertising) can influence clinical choices even when the scientific basis is uncertain. Furthermore, industry entanglement is 7.2% of surgeons disclosed LAT device sponsorships, and 13.3% learned LAT techniques directly from medical device representatives, bypassing traditional academic or peer-reviewed educational channels. Although none explicitly cited personal financial gain as a motivator, it is difficult to ignore the role of commercial pressures and incentives in the proliferation of LAT, especially in a field where the orthopaedics device market is valued in the tens of billions of dollars annually and has a long history of industry-driven practice changes.^39,47^

LAT Fixation Methods

The survey revealed a strong preference for suture anchors in LAT, with 75% of respondents indicating its use in ATFL repairs and similar preponderance of use at the deltoid. Suture anchors have perceived biomechanical advantages in providing secure fixation in a less osteoinvasive manner while allowing for biological healing.^ 50 ^ In contrast, interference screws appear to be less favored despite their historical use.

It is notable that among surgeons using LAT, suture buttons were the favored method of fixation at the syndesmosis. As evidence accumulates supporting the efficacy and potential benefits of suture button fixation for syndesmosis injuries, its adoption in clinical practice has increased. This trend reflects the ongoing evolution of surgical techniques in ankle syndesmosis repair, driven by a promulgation of research and improved study of clinical outcomes with LAT.^2,43,52^

Influential Factors Driving LAT Use

The survey data shows that LAT is more frequently used for elite athletes, manual laborers, or obese patients. These patients place greater mechanical stress on their joints and ligaments, which likely drives the perceived need for augmentation to reduce the risk of failure in repairs. For example, 106 respondents reported that they “significantly increase” LAT use or “use LAT every time” in elite athletes, and none reported any influence of decreased use. Intuitively, the anticipated level of physical and mechanical demand placed on the ligament postoperatively is a strong determinant of LAT use. This finding is consistent with prior clinical studies of LAT in the ankle and other anatomic sites that note potential advantages of shorter postoperative immobilization duration and more rapid return to play.^21,26,27,36,64^ In addition, multiple biomechanical studies at the ankle, knee, and elbow support the idea that LAT provides added stability over a repair or nonaugmented reconstruction.^5,37,50^ Although limited data exist, a prior study to identify risk factors for failure of a modified Broström’s procedure demonstrated that higher BMI was associated with worse outcomes on the 12-Item Short Form Health Survey (SF-12),^ 53 ^ thus lending credence to the idea that patients with increased BMI may benefit from LAT.^ 63 ^

Patient age may also factor into the decision-making process. LAT use is less influenced by advanced age in comparison to other factors. This could reflect concerns over healing potential and increased surgical risks in older populations, where the potential benefits of LAT may not outweigh the potential for increased operative time, cost, and complexity. Additionally, as has been considered in a recent systematic review of ACL reconstruction in patients >50 years old,^ 17 ^ older patients may be less likely to engage in high-demand activities that would justify the added stabilization provided by augmentation techniques.

Regional and Practice-Based Variations in LAT Adoption

North America had the highest adoption rates for LAT compared with all other geographic regions, at 89%. However, our non–North American sample was low, and our finding of statistically significant differences in rate of LAT use is fragile (FI = 3). Still, this variation could be attributed to several factors, including access to LAT materials, differences in health care funding, and regional preferences for conservative vs surgical management of ligament injuries in North America vs the other geographic regions. These findings coincide with prior literature demonstrating that North American costs for orthopaedic surgical care are some of the highest in the world.^17,45,57^ Notably, our findings differ somewhat from those of a recent survey of International Society of Arthroscopy, Knee Surgery and Orthopedic Sports Medicine surgeon members, which showed that sports surgeons in Asia reported using LAT the most (80%), followed closely by North America (75%), whereas those in Africa used it the least (59%).^ 31 ^

There was not a statistically significant difference in the reported rates of LAT use by surgeons in private, academic, and community hospital settings. Despite the potentially increased cost of LAT materials at the time of surgery, the added financial burden did not deter most surgeons from adopting these techniques. Many surgeons report learning LAT during their fellowship training, perhaps leading these treatments to become more rigorously incorporated into their long-term practices. We also found that concerns about cost did not significantly differ between surgeon practice settings. However, cost-related concerns may remain a barrier in lower-income regions or in health care systems with more strict cost-containment measures until standardized treatment recommendations about the use of LAT in the foot and ankle emerge.

The Future of LAT in Foot and Ankle Surgery

The data indicate a trend toward increased LAT use in the future. This could come to fruition as a result of a variety of factors, including expanded training opportunities, decreased costs with wider adoption, and emerging evidence supporting LAT’s efficacy in reducing injury recurrence rates and improving functional outcomes. A minority reported concerns that future studies may fail to demonstrate the clear benefits of LAT, or that emerging techniques could render current LAT methods obsolete. This skepticism reflects the need for high-quality, controlled and randomized studies to definitively establish the long-term outcomes of LAT compared with traditional repair methods. Perhaps in the future newer, less invasive techniques, such as biological augmentation or tissue engineering, could supplant LAT as a popular alternative to traditional ligament repairs, especially if they can achieve similar outcomes with lower costs or reduced surgical morbidity and complexity.

Limitations

Several limitations must be acknowledged. First, a highly probable response bias may have influenced the ratio of LAT users to non-LAT users as members were invited to participate in a survey regarding LAT. In particular, the low response rate raises the possibility that LAT users were more likely to respond, potentially skewing results toward higher usage rates. This may have influenced our results, particularly those addressing outcomes and benefits to LAT and the future trajectory of their adoption. Further, a large proportion of the AOFAS, and thus foot and ankle providers, did not respond to the survey, which introduces an element of uncertainty in whether trends in our sample differ from the population not surveyed. The low overall response rate (12.9%) raises the possibility of nonresponse bias, especially if surgeons who actively use LAT were more likely to complete the survey. This limits the generalizability of the observed rates of LAT use. Additionally, the survey cohort consisted solely of AOFAS members, which may limit the generalizability of these findings to the global orthopaedic community. Ultimately, we cannot draw definitive conclusions about global LAT practices and are limited to conclusions based on responses from a small proportion of surgeons within the AOFAS.

Finally, the survey did not capture detailed information on the severity of injuries or comorbidities. Future research should aim to stratify data based on injury or pathology type, severity, and patient-specific factors, such as activity level and overall health status, to provide a more nuanced understanding of when and why LAT is used in patients with foot and ankle pathology.

Conclusion

This survey paints a picture of the current state of LAT use among surgeons of the AOFAS. Although LAT is widely used for certain ligament repairs, particularly in ATFL pathology, its application is not routine in every repair. In other areas, such as hallux ligaments and PTFL, it remains far less common. The drivers of LAT adoption appear to be multifactorial, influenced by patient demographics, regional practices, and surgeon training. Although we did not find device commercialism or sponsorship to motivate LAT use, it is clear that industry is an important consideration for LAT adoption. There is substantial influence of industry in both education and device adoption. Thus, it remains imperative to approach the expanding use of LAT with skepticism regarding commercial influences and to demand higher standards of evidence and transparency regarding the commercial interests at play. These considerations highlight the need for independent, high-quality studies to define LAT’s true clinical value and inform evidence-based guidelines. Our results suggest that the use of LAT will continue in the future, with many surgeons anticipating increased usage as costs decrease and evidence grows. However, ongoing debates about the cost-effectiveness and long-term outcomes of LAT suggest that further research is necessary to fully define its role in orthopaedic foot and ankle surgery.

Supplemental Material