Ultrasound Examination of the Ligament Complex Within the Medial Aspect of the Ankle and Foot.

To properly diagnose and treat injuries to the ankle or foot, the physician must have good anatomical knowledge of the ligaments involved. The bundles can be distinguished and identified by ultrasound examination of the medial aspect, but this may be a challenging task. In the present illustrated study, we discuss how a detailed ultrasound examination can be made of the different ligaments within the medial aspect of the ankle and foot.

Morphology of the ligaments located on the medial side of the ankle and on the plantar surface of the foot.

To have biodynamic features, the feet have bones located in a special posture, the joints that keep together those bones, the ligaments that provide linkage to those joints, and tendons of muscles particularly which end the foot. This study aimed to research the morphology of the medial side and plantar ligaments. The study was conducted on a total of 30 feet belonging to 2 women and 13 men cadavers that exist at the Anatomy Department of the Medical Faculty of Uludag University. After the dissections, 61 parameters that belonging to the ligaments and general features of the foot, were evaluated. The statistical analysis of the collected data was evaluated by SPSS 20.0. According to the findings, while the descriptive statistics of the foot and the ligaments related to the foot, the statistically significant difference of any of the parameters wasn't observed when they were compared between the right and left sides of the foot. In terms of the correlative relations, the parameters that showed high correlation were chosen and 28 formulas were developed using regression analysis. We foresee that our findings of the features belonging to normal anatomic structures will deepen our knowledge besides providing important benefits before or during orthopedic and plastic surgery operations related to the region. Also, our findings were discussed by comparing the findings of similar studies belonging to many other researchers in literature, and our study's contribution to the literature was evaluated.

Biomechanical Analysis of Midfoot Instability After Bifurcate Ligament Injury and Ankle Brace Application: A Cadaveric Study.

This cadaveric study investigated the biomechanical characteristics and stabilizing contribution of the bifurcate ligament using a multidirectional loading method and assessed the stabilizing effect of a brace after injury of the ligament. Eight freshly frozen cadaveric feet were tested for forefoot torque in inversion, eversion, adduction, and plantarflexion. Each band of the bifurcate ligament was transected sequentially, and the contribution of each portion of the ligament, as well as the stabilizing effects of the ankle brace, were examined. Stability decreased substantially after calcaneocuboid ligament transection for inversion and adduction loading. Bracing restored some stability, except for the adduction loading direction, for which it had only limited effect. The data indicate that inversion and adduction loading are strongly related to bifurcate ligament injury. The stabilizing effect of the ankle brace may have limited effectiveness for loads under adduction.

Morphological features of the bifurcated ligament.

INTRODUCTION: Damage to the bifurcate ligament is one of the most difficult injuries to diagnose from imaging techniques. A probable reason for this is that the morphological characteristics of this structure have yet to be sufficiently elucidated. We, therefore, endeavored to elucidate the morphological characteristics of the bifurcate ligament through a large-scale study involving numerous specimens. MATERIALS AND METHODS: This study included 100 feet from 52 formalin-fixed cadavers. The bifurcate ligament was classified into three types: presence of both calcaneonavicular ligament and calcaneocuboid ligament (Type I); absence of calcaneocuboid ligament (Type II); and absence of calcaneonavicular ligament (Type III). Morphological characteristics of the bifurcate ligament were determined by measuring fiber bundle length, width, and thickness at the center of each ligament. RESULTS: This classification resulted in 68 Type I feet (68%), 32 Type II feet (32%), and 0 Type III feet (0%). The calcaneonavicular ligament was 20.8 ± 2.9 mm long, 4.9 ± 1.2 mm wide, and 3.8 ± 1.1 mm thick. The calcaneocuboid ligament was approximately 10.5 ± 2.7 mm long, 4.7 ± 2.4 mm wide, and 1.5 ± 0.6 mm thick. The bifurcate ligament was located deep under the extensor hallucis brevis and extensor digitorum brevis muscles in all specimens. The calcaneal origin of the calcaneonavicular ligament was situated deep under the interosseous talocalcaneal ligament in all specimens. Two sides were identified in which the calcaneocuboid ligament was located deep under the dorsal calcaneocuboid ligament. CONCLUSION: Such variations and positional relationships were suggested to be factors complicating the diagnostic imaging of bifurcate ligament injuries. The present study results will likely form useful basic data for diagnostic imaging.

The Potential of Endoscopic Spring Ligament Repair in Flatfoot Reconstruction.

BACKGROUND: Spring ligament fulfills 2 main important functions: one, supporting the head of the talus and stabilizing the talonavicular joint, and the other, maintaining the longitudinal arch by acting as a static support. In this preliminary report, we describe an endoscopic repair for spring ligament injuries with modified portals. METHODS: We performed a retrospective case series study from February 2019 to January 2022. Posterior tibial tendon and/or associated bone deformities were assessed at the same surgical procedure. All patients were ≥18 years old and they had more than 6 months of follow-up. The procedure was performed in 11 patients. Mean age was 46 years (range 18-63). Ten had concomitant bony realignment surgery, and 8 had posterior tibial tendon surgery. RESULTS: In all patients, endoscopic spring ligament repair could be technically done. The modified portals were used in all procedures as described in the surgical technique. Three patients had a superficial lesion, 1 had a rupture <5 mm, 7 had a rupture >5 mm but not a complete rupture through the entire spring ligament. Most of the patients had good clinical results from the surgery that included endoscopic spring ligament debridement and/or repair at 2 years follow up. CONCLUSION: In this small series we found that endoscopy may be an effective technique to diagnose and treat incomplete spring ligament injuries. LEVEL OF EVIDENCE: Level IV, retrospective case series.

Foot length - A reliable predictor of posterior tibial tendon thickness: A cadaveric study.

Background: Tibialis posterior tendon, deltoid ligament and spring ligament are the three most important structures on the medial aspect of the foot. They contribute to the stability of the foot and ankle and also to the maintenance of the arches of the foot. These structures get affected and dimensions get disrupted in various traumatic and degenerative conditions. Normal range of dimensions of these structures has not been studied in an Indian population. Our objective is to define the normal thicknesses of these structures using a cadaveric model. We also hypothesize that longer the foot, higher stresses on these structures and hence thicker they will be. We aim to assess this hypothesis as well. Methods: Dissection of the medial aspect of the foot was done on twenty cadaveric below knee specimens. Tibialis posterior tendon was identified and its thickness was measured. Deltoid and plantar calcaneonavicular ligaments were identified. Their lengths and thicknesses were measured. Length of the feet was also measured prior to dissection. Statistical analysis was done using the data obtained. Results: Mean tibialis posterior thickness was 7.0165 ± 0.387 mm. Mean deltoid thickness was 5.124 ± 0.28 mm. Its mean length was 21.328 ± 2.22 mm. Mean plantarcalcaneonavicular ligament thickness was 2.491 ± 1.120 mm. Thicknesses of the tibialis posterior tendon and plantarcalcaneonavicular ligament correlated significantly with the length of the foot. Conclusion: The thicknesses of the tibialis posterior tendon and plantar calcaneonavicular ligament are shown to be a function of and significantly proportional to the length of the foot. This helps the surgeon to estimate the thicknesses which the structures had prior to the pathology, in order to recreate the non-pathological anatomy after a tendon transfer or a reconstruction procedure. The normal thicknesses of tibialis posterior, deltoid and plantar calcaneonavicular ligaments are described for an Indian setting and deviations can be used to assess various pathologies of the foot and ankle affecting these structures.

Quantifying increased lateral column instability in Adult Acquired Flatfoot Deformity (AAFD).

AAFD comprises ligamentous failure and tendon overload, mainly focused on the symptomatic posterior tibial tendon and the spring ligament. Increased lateral column (LC) instability arising in AAFD is not defined or quantified. This study aims to quantify the increased LC motion in unilateral symptomatic planus feet, using the contralateral unaffected asymptomatic foot as an internal control. In this case matched analysis, 15 patients with unilateral stage 2 AAFD foot and an unaffected contralateral foot were included. Lateral foot translation was measured as a guide to spring ligament competency. Medial and LC dorsal sagittal instability were assessed by direct measurement of dorsal 1st and 4th/5th metatarsal head motion and further video analysis. The mean increase in dorsal LC sagittal motion (between affected vs unaffected foot) was 5.6 mm (95% CI [4.63-6.55], p < 0.001). The mean increase in the lateral translation score was 42.8 mm (95% CI [37.48-48.03], p < 0.001). The mean increase in medial column dorsal sagittal motion was 6.8 mm (95% CI [5.7-7.8], p < 0.001). Video analysis also showed a statistically significant increase in LC dorsal sagittal motion between affected and unaffected sides (p < 0.001). This is the first study that quantifies a statistically significant increased LC dorsal motion in feet with AAFD. Understanding its pathogenesis and its link to talonavicular/spring ligament laxity improves foot assessment and may allow the development of future preventative treatment strategies.

Differential contribution of lateral plantar foot ligaments to lateral column stability - A cadaver based sectioning analysis.

Lateral column (LC) instability occurs in adult acquired flatfoot deformity (AAFD). Differential ligament contribution to LC stability is unknown. The primary aim was to quantify this by using cadaver sectioning of lateral plantar ligaments. We also determined the relative contribution of each ligament to dorsal translation of the metatarsal head in the sagittal plane. 17 below-knee cadaveric specimens, preserved by vascular embalming method, were dissected to expose plantar fascia, long/short plantar ligaments (L/SPL), calcaneocuboid (CC) capsule and inferior 4th/5th tarsometatarsal (TMT) capsule. Dorsal forces of 0 N, 20 N and 40 N were applied to the plantar 5th metatarsal head after sequential ligament sectioning in different orders. Pins provided linear axes on each bone, allowing relative angular bone displacements to be calculated. Photography and ImageJ processing software were then used for analysis. The LPL (and CC capsule) had the greatest contribution to metatarsal head motion (107 mm) after isolated sectioning. In the absence of other ligaments, sectioning these resulted in significantly increased hindfoot-forefoot angulation (p ≤ 0.0003). Isolated TMT capsule sectioning demonstrated significant angular displacement even when other ligaments remained intact (with intact L/SPL, p = 0.0005). CC joint instability required both LPL and capsular sectioning for significant angulation to occur, whilst TMT joint stability was largely dependent on its capsule. The relative contribution of static restraints to the lateral arch has not yet been quantified. This study provides useful information on relative ligament contribution to both CC and TMT joint stability, which may in turn improve understanding of surgical interventions used to restore arch stability.

Normal and Diseased Imaging: Ultrasound/MRI.

The lesser metatarsophalangeal joint plantar plate and calcaneonavicular (spring) ligament are highly specialized soft tissue structures within the foot, consisting partly of fibrocartilage and capable of withstanding high compressive and tensile loads. Preoperative advanced imaging, in the form of point-of-care ultrasound and MRI, has become indispensable for surgeons hoping to confirm, quantify, and better localize injuries to these structures before surgery. This article describes the technical considerations of ultrasound and MRI and provides examples of the normal and abnormal appearances of these structures. The pros and cons of each imaging modality are also discussed.

The Spring Ligament Complex-Anatomy and Function.

This article provides an overview of the soft tissue contributions to the normal structures that surround the talo-calcaneal-navicular (TCN) joint of the human arch. The TCN joint has a multiplanar range of motion that makes it essential to the kinetic coupling that links the forefoot and hindfoot. The soft tissue connection surrounding this joint is known as the spring ligament complex. More accurate knowledge of the anatomy of this complex will enhance the understanding of its role in the support of the head of the talus and, potentially, its critical interactions with the normal or abnormal function of the arch.

Physical Examination of the Ankle: A Review of the Original Orthopedic Special Test Description and Scientific Validity of Common Tests for Ankle Examination.

OBJECTIVES: To review the literature, identify and describe commonly used special tests for diagnosing injury to the ligaments of the ankle complex, present the distinguishing characteristics and limitations of each test, and discuss the current evidence for the clinical use of each test. DATA SOURCES: Multiple PubMed (1920-2018) and CINAHL (1920-2018) searches were conducted and various musculoskeletal examination textbooks were reviewed to examine common orthopedic tests used to assess the ankle. The articles were reviewed for additional references and the search continued until the original description was found when possible. STUDY SELECTION: All articles discussing the performance of the test or its validity (ie, sensitivity and specificity) were reviewed and summarized. DATA EXTRACTION: Articles were reviewed for additional references and the search continued until the original description was found when possible. DATA SYNTHESIS: The literature was reviewed, commonly used special tests for diagnosing ankle injuries were identified and described, distinguishing characteristics and limitations of each test were presented, and the current evidence for the clinical use of each test was discussed. CONCLUSIONS: A complete physical examination is critical in the diagnosis of ankle injuries. The combination of available information such as mechanism of injury, all signs and symptoms, and changes in gait, is key to a conclusive and correct diagnosis. Clinicians should be aware of the severely limited evidence supporting the use of many commonly used special tests. Applying evidence from the literature will improve diagnostic accuracy. Further research is needed to understand the performance ability of special tests, both individually and when grouped as part of a test battery.

Anatomico-radiological Study of the Bifurcate Ligament of the Foot with Clinical Significance.

Introduction Lateral ankle sprain caused by forcible plantar flexion and inversion of the foot commonly damages the anterior talofibular ligament and other ligaments. Unfortunately, involvement of the bifurcate ligament (BL) is often overlooked when assessing such injuries in clinical practice and identification of this ligament on magnetic resonance (MR) scans can be challenging. Anatomically, the BL is a Y-shaped structure with two bands: the calcaneonavicular ligament (CNL) and calcaneocuboid ligament (CCL). There are few anatomical studies on the morphometric characteristics of the BL and even fewer biomechanical studies. Therefore, the objective of this anatomico-radiological study was to investigate the morphology of the BL using a multifaceted approach, and classify the fiber characteristics of the CNL and CCL. Materials and methods We measured the length and the width of 53 embalmed cadaveric feet. Meticulous dissection of each foot was performed to expose the BL. Measurements of the length, width, thickness, and shape of the CNL and CCL were taken using a digital caliper. We also documented the fiber orientation of each ligament, and used a goniometer to measure the bifurcation angle between the CNL and CCL via two methods. Confirmatory histologic analysis of the ligaments was performed and digital radiographs of the ligaments with attached radiopaque monofilament were taken. We also included an MR scan of the BL. Using descriptive and inferential statistics, we documented any significant relationships between the variables. Results  Mean (range) age at death of cadavers was 76 (42-94) years. The CNL was found in all the feet and the CCL was not present in 9.4% of the feet. Mean (standard deviation) length of the CNL and CCL was 22.7 (4.12) mm and 10.9 (2.53) mm, respectively. Mean (standard deviation) thickness of the CNL and CCL was 3.23 (1.56) mm and 1.48 (0.71) mm, respectively. Related to ligament morphology, the CNL was most frequently cord shaped (67.92%) and the CCL was most frequently flat shaped (83.33%). The mean bifurcation angle measured 32.75o and 29.31o in methods 1 and 2, respectively. The correlation between the two measured angles was very strong (p < 0.001). Discussion We found that 90.6% of feet had both the CNL and CCL, 9.4% had the CNL and no CCL, and none (0%) had the CCL and no CNL. These frequencies are similar to a recent Japanese study. Our sample of donors were American and predominantly white. Whether the difference in frequencies between the studies is related to ethnicity is unknown and requires future investigation. Interestingly, on average the CNLs were twice as long and twice as thick as the CCLs. The CCLs tended to be wider distally and tapered compared to the CNLs. Conclusions Our findings better classify the morphology and fiber orientation of the BL. Coupled with the radiographs and MR scan, our data may be of particular value to radiologists and surgeons. Our BL fiber orientation classification system and angle measurements can pave the way for future biomechanical studies to investigate any relationships between fiber type, angle, and strength of the constituent bands. More accurate descriptions of the BL should lead to improved diagnosis and treatment of ligamentous injuries of the foot.

Spring Ligament Instability.

The crucial role of the spring ligament complex within the pathologic process that leads to flatfoot deformity has evolved recently. There has been improvement in the anatomic knowledge of the spring ligament and understanding of its complex relationship to the deltoid complex and outstanding advances in biomechanics concepts related to the spring ligament. Optimization of flatfoot treatment strategies are focused on a renewed interest in the spring ligament and medial soft tissue reconstruction in concert with bony correction to obtain an adequate reduction of the talonavicular deformity and restoration of the medial longitudinal arch.

What to Do with the Spring Ligament.

The spring ligament complex is an important static restraint of the medial longitudinal arch of the foot and its failure has been associated with progressive flatfoot deformity. Reconstruction of the spring ligament complex is most appropriate in stage II posterior tibial tendon dysfunction, before severe peritalar subluxation and rigid deformity develops. Although an understanding of the spring ligament complex and its contribution to medial arch stability has grown, there is no unanimously accepted surgical technique that has consistently demonstrated satisfactory outcomes. This article reviews the pathoanatomy of the spring ligament complex and the role of spring ligament reconstruction in acquired flatfoot deformity, and highlights current research.

Spring ligament complex: Illustrated normal anatomy and spectrum of pathologies on 3T MR imaging.

The spring (plantar calcaneonavicular) ligament complex connects the calcaneus and navicular bone of the foot and serves as the primary static stabilizer of the medial longitudinal arch of the foot. In this article, we describe the normal anatomy of the spring ligament complex, illustrate 3T magnetic resonance imaging appearances in its normal and abnormal states, and discuss the pathological associations with relevant case examples.

Neutral heel lateral push test: The first clinical examination of spring ligament integrity.

INTRODUCTION: The spring (calcaneonavicular) ligament is an intricate multiligament complex whose primary role is to stabilise the medial longitudinal arch and head of talus. Clinical suspicion of a spring ligament injury in isolation is roused when persistent medial midfoot pain is present with associated pes planus following trauma. METHOD: We undertook a cadaveric study on 21 specimens to assess the use of a neutral heel lateral push test to examine the spring ligament in a standardised procedure, measuring lateral translation with graduated antegrade and retrograde defunctioning of surrounding structures and the spring ligament. RESULTS: In all specimens, a significant displacement occurred on incision of the spring ligament regardless of order of dissection. The degree of displacement increased by an insignificant amount as surrounding structures were incised at each incremental force applied. DISCUSSION: The neutral heel push test is the first clinical examination to be described to determine integrity of the spring ligament complex. Our study objectively demonstrates that lateral displacement in relation to the mid and hind-foot is influenced most significantly by the integrity of the spring ligament and to a lesser extent by tibialis posterior and flexor digitorum longus.

Anatomical reconstruction of the spring ligament complex: "internal brace" augmentation.

The calcaneonavicular (spring) ligament complex is a critical static support of the medial arch of the foot. Compromise of this structure has been implicated as a primary causative factor of talar derotation leading to the clinical deformity of peritalar subluxation. Few procedures have been described to address this deficiency. The technique we describe here is a simple yet effective method to reconstruct the spring ligament complex that can easily be used in conjunction with other more commonly used procedures for extra-articular reconstructions of this deformity. We believe this procedure allows for a more powerful deformity correction and may decrease dependency on other nonanatomic reconstructive procedures.

Flexible cavovarus foot in children and adolescents.

Flexible cavovarus feet in children and adolescents can be challenging. A careful history and physical examination are paramount for determining the best treatment strategy and a multitude of options are available. Specific treatment strategies should be individualized and any bony correction must be in conjunction with a muscle balancing procedure. Well-timed soft tissue and occasionally bony procedures can delay the progression of deformity. These patients are monitored long term because further treatment may be required.