Biomechanical Evaluation of Spring Ligament Augmentation With the FiberTape Device in a Cadaveric Flatfoot Model

Simulated Weightbearing and Articular Injury From Transarticular Screws in a Ligamentous Lisfranc Injury Model

BACKGROUND

Transarticular screw fixation is a common surgical treatment for tarsometatarsal ligamentous (Lisfranc) injuries. Iatrogenic damage to articular cartilage from screw placement, however, has been thought to potentially lead to increased risk of tarsometatarsal (TMT) joint arthritis after initial injury. To date, no study has evaluated the effect of weightbearing on articular cartilage after screw fixation. The aim of this study was to create a Lisfranc injury and quantify and compare articular damage due to screw fixation before and after simulated weightbearing.

METHODS

A ligamentous Lisfranc injury was created in 10 cadaveric specimens and treated with transarticular screws. Specimens were cycled for 1000 cycles at 250 N to simulate 2 weeks of physiologic weightbearing. Rotation and diastasis across the Lisfranc complex were measured. Articular injury as a percentage of total articular surface was measured using digital imaging of the first and second TMT joint before and after simulated weightbearing. Comparisons between articular damage were made and statistical analysis was performed.

RESULTS

Simulated partial weightbearing increased articular injury 1.44-fold (P < .001). The second metatarsal (M2) showed the greatest increase (1.54-fold, P = .0047), whereas the first (M1) showed the least (1.35-fold, P = .0083). Increases seen at the medial (1.43-fold, P = .0387) and middle cuneiform (1.44-fold, P = .0292) were intermediate between the values seen at M2 and M1.

CONCLUSION

Articular damage from transarticular screw fixation significantly increased after simulated partial weightbearing. This may increase the risk of arthritis and future morbidity when using transarticular screws for the treatment of ligamentous Lisfranc injuries.

CLINICAL RELEVANCE

Iatrogenic damage to articular cartilage due to screw fixation of ligamentous Lisfranc injuries may be increased with weightbearing.

Spring Ligament Reconstruction for Progressive Collapsing Foot Deformity: Contemporary Review

The spring ligament is one of the main stabilizers of the medial arch of the foot and the primary static supporter of the talonavicular joint. Attenuation or rupture of this ligament is thought to play a central role in the pathophysiology of progressive collapsing foot deformity. Traditional correction of flexible flatfoot consists of posterior tibial tendon augmentation along with various osteotomies or hindfoot fusions. Repair or reconstruction of the spring ligament has not been as widely pursued. In recent years, newer techniques have been explored and may improve outcomes of traditional procedures, or possibly entirely replace some osteotomies. Combined spring-deltoid ligament reconstruction is also gaining traction as a viable technique, particularly as the ankle begins to deform into valgus. This review summarizes the variety of nonanatomic and anatomic reconstruction techniques that have been described, including autologous tendon transfers, allografts, and synthetic augmentation. Although many have only been characterized in biomechanical cadaver studies, this article reviews preliminary clinical studies that have shown promising results. There is a need for more high-quality studies evaluating the clinical, radiographic, and patient-reported outcomes following spring ligament reconstruction.

Ligament Insufficiency with Flatfoot: Spring Ligament and Deltoid Ligament

The objective of this article was to review the deltoid ligament and spring ligament specifically as they pertain to ligament insufficiency and adult-acquired flatfoot deformity. Discussion includes the normal and abnormal biomechanical forces that extend through these ligaments in normal and flatfoot deformity. Current literature related to spring ligament repair as part of the flatfoot deformity reconstruction is also reviewed.

Biomechanical Comparison of Fiber Tape Device Versus Transarticular Screws for Ligamentous Lisfranc Injury in a Cadaveric Model

BACKGROUND

The preferred method of fixation and surgical treatment for ligamentous Lisfranc injuries is controversial. Transarticular screws, bridge plating, fusion, and flexible fixation have been described, yet none have demonstrated superiority. Furthermore, screw fixation and plating often require secondary surgery to remove implants, leading surgeons to seek alternative fixation methods.

PURPOSE

To compare transarticular screws and a fiber tape construct under a spectrum of biomechanical loads by evaluating the diastasis at 3 joints in the Lisfranc complex.

STUDY DESIGN

Controlled laboratory study.

METHODS

Eight matched pairs of fresh, previously frozen lower extremity cadaveric specimens were fixed with either 2 cannulated transarticular crossed screws or a fiber tape construct with a supplemental intercuneiform limb. The diastasis between bones was measured at 3 midfoot joints in the Lisfranc complex: the Lisfranc articulation, the second tarsometatarsal joint, and the intercuneiform joint. Measurements were obtained for the preinjured, injured, and fixation conditions under static loading at 50% donor body weight. Specimens then underwent cyclic loading performed at 1 Hz and 100 cycles, based on 100-N stepwise increases in ground-reaction force from 100 to 2000 N, to simulate postoperative loading from the partial weightbearing stage to high-energy activities. Failure of fixation was defined as diastasis ≥2 mm at the Lisfranc articulation (second metatarsal-medial cuneiform joint).

RESULTS

There were no significant differences in diastasis detected at the Lisfranc articulation or the intercuneiform joint throughout all loading cycles between groups. All specimens endured loading up to 50% body weight + 1400 N. Up to and including this stage, there were 2 failures in the cannulated transarticular crossed-screw group and none in the fiber tape group.

CONCLUSION

The fiber tape construct with a supplemental intercuneiform limb, which does not require later removal, may provide comparable biomechanical stability to cannulated transarticular crossed screws, even at higher loads.

CLINICAL RELEVANCE

Ligamentous Lisfranc injuries are common among athletes. Therefore, biomechanical evaluations are necessary to determine stable constructs that can limit the time to return to play. This study compares the biomechanical stability of 2 methods of fixation for ligamentous injury through a wide spectrum of loading, including those experienced by athletes.

A Critical Biomechanical Evaluation of Foot and Ankle Soft Tissue Repair

The objective of this article is to review the biomechanical stresses that occur during normal physiologic function of lower extremity soft tissue anatomic structures and to use this as a baseline for a critical analysis of the medical literature because it relates to surgical reconstruction following injury. The Achilles tendon, anterior talofibular ligament, plantar plate, and spring ligament are specifically evaluated.

Operative Management: Spring Ligament

Pes planovalgus is a multiplanar deformity consisting of a combination of hindfoot valgus, collapse of the medial longitudinal arch, forefoot varus, and forefoot abduction. This deformity is often associated with posterior tibial tendon dysfunction. Collapse of the medial longitudinal arch increases stress to the static stabilizers of the medial column including the deltoid ligament, spring ligament, plantar fascia, plantar and talocalcaneal interosseous ligaments, as well as the talonavicular and naviculocuneiform capsules. There is a higher incidence of concomitant spring ligament pathology in pes planovalgus deformity and posterior tibial tendon dysfunction based on magnetic resonance imaging and intraoperative observation than in other static stabilizers.

Adult Acquired Flatfoot Deformity

Adult acquired flatfoot deformity (AAFD) is a condition commonly seen by orthopaedic surgeons. Posterior tibial tendon dysfunction is thought to be the initial pathoanatomic etiology that leads to this deformity. Successful resolution of the pain associated with AAFD can be achievable with nonsurgical methods. Patients who continue to have pain or functional limitations despite nonsurgical treatment can find improvement with appropriately selected surgical interventions. This article addresses new advances in treatment based on the stage of AAFD and will identify areas of continued development with a focus on surgical management. The literature continues to evolve as demonstrated by a recent update regarding the nomenclature and treatment of this condition to progressive collapsing flatfoot deformity. Future goals of research include understanding the natural history of the disease, from asymptomatic to symptomatic, and studying a wide array of newer treatments and implants that have not been prospectively evaluated.

Spring and Deltoid Ligament Insufficiency in the Setting of Progressive Collapsing Foot Deformity. An Update on Diagnosis and Management

The spring ligament and deltoid ligament are important stabilizers of the medial ankle. Together, they form a complex along the medial ankle and foot that is critical to stability of both the ankle and the medial longitudinal arch. Incompetence of the spring and deltoid ligament is a component of both the early and late stages of progressive collapsing foot deformity. As the importance of this medial ligament complex has been recognized, repair and reconstruction of these ligaments have progressively evolved, initially as separate reconstructions, and more recently as combined techniques.

Current Trends in Treatment of Injuries to Spring Ligament

The spring ligament is the main static supporter of the medial longitudinal arch. Identifying every detail of the pathophysiology of each condition in which these structures are involved is the key to an appropriate approach and treatment. Isolated reconstruction of the posterior tibial tendon present long-term results with a high failure rate. It is important to diagnose spring ligament injuries because of the probable consequences if not treated, such as acquired flatfoot deformity and loss of correction of treated flatfoot. The option of surgical treatment is discussed in this article.

Biomechanical Comparison of Fibertape Device Repair Techniques of Ligamentous Lisfranc Injury in a Cadaveric Model

BACKGROUND

Lisfranc ligamentous injuries are complex, and their treatment, along with the preferred method of fixation, is controversial. Implementing a flexible synthetic augmentation device (fibertape) has been described as an alternative to traditional screw fixation. This biomechanical study evaluated two fibertape devices with interference screw fixation: InternalBrace, and InternalBrace with supplementary intercuneiform stabilization.

METHODS

The diastasis and relative angular displacement between bones were measured at three midfoot joints in the Lisfranc articulation. Measurements were obtained for the pre-injured, injured, and post-fixation stages under static loading. Specimens then underwent stepwise increases in cyclic loading performed at 1 Hz and 100 cycles, at 100 N ground reaction force intervals from 500 to 1200 N to simulate postoperative loading, and then up to 1800 N to simulate high loads. Failure of fixation was defined as diastasis greater than 2 millimeters at the second-metatarsal - medial-cuneiform joint.

RESULTS

InternalBrace specimens demonstrated failures in 3 of 9 (33%) specimens at cyclic loads of 1000 N. Conversely, InternalBrace with Supplementary Limb specimens had 1 failure at 1200 N. The difference in diastasis at the second metatarsal-medial cuneiform joint was statistically significant between the two groups at higher loads of 1600N (p = 0.019) and 1800N (p = 0.029).

CONCLUSION

The use of InternalBrace for ligamentous Lisfranc injuries appears to provide a biomechanically viable alternative for withstanding early postoperative protected weight bearing. Furthermore, the use of a supplementary limb in addition to the InternalBrace fibertape fixation method appears to enhance its biomechanical efficacy.

A valuable option: Clinical and radiological outcomes of braided suture tape system augmentation for spring ligament repair in flexible flatfoot

BACKGROUND

The purpose of this study was to evaluate the clinical and radiological outcomes of the briaded suture tape system augmentation in the treatment of flexible flatfoot.

METHODS

Patients who underwent suture tape system augmentation in addition to spring ligament repair and flexor digitorum longus (FDL) transfer were reviewed. Clinical and radiological outcomes were studied. The results were compared to a matched control group who underwent the conventional surgical treatment, which involved FDL transfer only or FDL transfer plus medial sliding calcaneal osteotomy.

RESULTS

A total of 40 patients (11 males and 29 females) who underwent hindfoot reconstruction for flexible flatfoot (Johnson stage 2) were reviewed. There were 18 patients in the suture tape system group and 22 patients in the control group. In the suture tape system group, there was excellent improvement in patients' symptoms, AOFAS score (97.9 improved from 76.7) and significantly more number of patients with stable single leg stance. Radiographic parameters improved postoperatively too.

CONCLUSIONS

This is the first clinical study which studied the outcome of suture tape system augmentation for spring ligament repair. Patients with suture tape system reconstruction showed more number of patients with single leg stance and better correction of forefoot abduction. It is a reasonable component of hindfoot reconstruction.

[Surgical procedures for the correction and stabilization of pes planovalgus]

The medial column of the foot is a relevant factor of the pathogenesis of pes planovalgus. Crucial anatomic structures are the tibiocalcaneonavicular ligament complex, the naviculocuneiform joints, including the ossa cuneiformia, and the first tarsometatarsal joint. A combination of bony and soft tissue reconstructive techniques must, therefore, be taken into account when treating pes planovalgus. The present article presents stabilizing and correcting surgical procedures for the medial column of the foot, including basic anatomy and biomechanics.

Anterior Syndesmotic Augmentation Technique Using Nonabsorbable Suture-Tape for Acute and Chronic Syndesmotic Instability

Syndesmotic instability is a source of significant pain and disability. Both subtle instability and gross diastasis, whether acute or chronic, require stabilization and may benefit from reconstruction with ligamentous augmentation. The use of nonabsorbable suture-tape has emerged as a promising operative strategy, allowing surgeons to anatomically reconstruct the syndesmosis, in particular the anterior inferior tibiofibular ligament. The current work provides a detailed description of the technique and preliminary results of a patient cohort treated using nonabsorbable suture-tape for syndesmotic augmentation.Level of Evidence: Level V, expert opinion.

Comparative Study of Spring Ligament Reconstructions Using Either Hamstring Allograft or Synthetic Ligament Augmentation

BACKGROUND

Idiopathic flatfeet are usually caused by attenuation of the medial soft tissues rather than a lateral osseous deficiency. Debate continues on whether spring ligament attenuation or posterior tibial tendon (PTT) dysfunction is the initial driver for the deformity. Our comparative prospective study aimed to quantify the radiological and clinical outcomes of 2 techniques for spring ligament reconstruction using a hamstring graft or a synthetic ligament.

METHODS

Seventeen spring ligament reconstructions (SLRs) were performed in 17 patients using synthetic ligament augmentation and 16 SLRs were performed using hamstring allograft in 13 patients. Additional procedures such as gastrocnemius recession, PTT advancement, flexor digitorum longus transfer, and calcaneal osteotomy were performed as required. A minimum of 12 months of follow-up was available for all cases. Radiographic analysis was performed with standardized parameters.

RESULTS

Following SLR with synthetic ligament augmentation, all radiological parameters significantly improved (P < .05). Hamstring allograft SLR also demonstrated significantly improved radiographic parameters in all but Meary's line at final follow-up. At 12 months, patient outcome scores were significantly better in the synthetic ligament group.

CONCLUSION

Reconstruction of the spring ligament using either hamstring allograft or synthetic ligament augmentation provided significant improvements in radiological alignment; however, superior patient-reported outcomes were found in the synthetic ligament augmentation group.

LEVELS OF EVIDENCE

Level III, retrospective cohort study.

Adult rigid flatfoot: Triple arthrodesis and osteotomy

To analyze the efficacy of arthrodesis combined with osteotomy applied to subtalar, calcaneocuboid, and talonavicular joints for the treatment of adult rigid flatfoot.This retrospective study included 29 adult patients with rigid flatfoot who underwent triple arthrodesis combined with osteotomy from January 2015 to December 2017. All patients suffered from stage III of adult acquired flatfoot. Patients returned for a clinical and radiologic follow-up evaluation at an average of 19.5 (range, 15-27) months postoperatively. Outcomes were assessed by comparing pre- and postoperative AOFAS scores, VAS pain scores, and Karlsson scores, and the radiographic assessment including Meary, Pitch, and Kite angles.Twenty six patients returned for final evaluation. Twenty four patients had an excellent or good outcome on patient subjective self-assessment. All the VAS scores, AOFAS scores, and Karlsson scores at final follow-up showed different extents of improvement. The mean Meary angle significantly decreased from 25.8 ± 5.4 degrees preoperatively to 6.9 ± 7.7 degrees at final follow-up, and the mean Pitch angle improved markedly from 12.5 ± 3.7 points preoperatively to 23.2 ± 4.1 points at final follow-up (P < .001).Arthrodesis combined with osteotomy can effectively correct calcaneal valgus deformity, restore arch structure, and relieve foot pain in adult rigid flatfoot.

Flexible Fixation in Foot and Ankle Surgery

Flexible fixation has been described and utilized in various aspects of foot and ankle surgery over the past several decades. In regards to ankle surgery, flexible fixation devices have been used for stabilization of the ankle syndesmosis and augmentation of lateral collateral ankle ligament repair. In the foot, flexible fixation devices have been incorporated into hallux valgus or varus correction, Lisfranc injury repair, and more recently spring ligament repair augmentation. This article reviews the various applications for flexible fixation in foot and ankle surgery, as well as evidence-based literature on surgical applications and clinical outcomes.