Spring Ligament Instability

Ultrasound assessment of the spring ligament and posterior tibial tendon in healthy subjects: A descriptive study

BACKGROUND

The main aim of this study was to ultrasonographically analyse the thickness and the relationship between the Superomedial Bundle of the Spring Ligament and the Posterior Tibial Tendon in healthy subjects and its relationship with different epidemiological variables.

METHODS

Fifty-five healthy feet with a mean of 47 years old measuring the same ultrasound model and researcher. Demographic variables (age, sex, laterality, BMI, type of sports activity performed, and type of work activity) were collected from all participants. The thickness of the PTT and the Spring Ligament was measured in both longitudinal and transverse diameters. The intraclass correlation coefficient (ICC) was also analysed to assess the agreement of the measurements between a researcher and the ultrasound specialist radiologist.

RESULTS

The mean thickness of the Spring ligament was 5.07 mm (95 % CI 4.75-5.38), while that of the PTT in its long axis was 3.58 mm (95 % CI 3.37-3.79). Regarding the interobserver agreement analysis, the intraclass correlation coefficient for measurements between observers was 0.91 (CI95 %: 0.698-0.977) which denotes a high degree of similarity between the clinician and the radiologist.

CONCLUSION

This study describes the relationships between the thickness of the posterior tibial tendon and the superomedial Bundle of the Spring ligament in healthy subjects, as well as their variability according to certain epidemiological variables such as age, gender, occupation, and sport. On the other hand, the measurements taken by a researcher high agreement with those taken by a radiologist specialized in ultrasound.

Hydroxyapatite deposition disease (HADD) of the spring ligament: an unusual cause of medial foot pain

Foot pain is one of the most common presenting complaints in orthopaedic clinical practice and can be attributed to a multitude of pathologies in the various osseous structures, ligaments, and tendons of the foot. The spring ligament complex (SLC) between the calcaneum and navicular supports the talus and plays a major role in the static stability of the medial longitudinal arch of the foot. Although calcific ligamentous enthesopathy around the ankle has been described in the literature, we report the first case of its kind affecting the SLC in a 51-year-old male with medial foot pain and no history of trauma. We highlight the role of radiological interventions in the diagnosis and effective management using ultrasound (US)-guided barbotage.

Unique shape variations of hind and midfoot bones in flatfoot subjects-A statistical shape modeling approach

Flatfoot deformity is a prevalent hind- and midfoot disorder. Given its complexity, single-plane radiological measurements omit case-specific joint interaction and bone shape variations. Three-dimensional medical imaging assessment using statistical shape models provides a complete approach in characterizing bone shape variations unique to flatfoot condition. This study used statistical shape models to define specific bone shape variations of the subtalar, talonavicular, and calcaneocuboid joints that characterize flatfoot deformity, that differentiate them from healthy controls. Bones of the aforementioned joints were segmented from computed tomography scans of 40 feet. The three-dimensional hindfoot alignment angle categorized the population into 18 flatfoot subjects (≥7° valgus) and 22 controls. Statistical shape models for each joint were defined using the entire study cohort. For each joint, an average weighted shape parameter was calculated for each mode of variation, and then compared between flatfoot and controls. Significance was set at p < 0.05, with values between 0.05 ≤ p < 0.1 considered trending towards significance. The flatfoot population showed a more adducted talar head, inferiorly inclined talar neck, and posteriorly orientated medial subtalar articulation compare to controls, coupled with more navicular eversion, shallower navicular cup, and more prominent navicular tuberosity. The calcaneocuboid joint presented trends of a more adducted calcaneus, more abducted cuboid, narrower calcaneal roof, and less prominent cuboid beak compared to controls. Statistical shape model analysis identified unique shape variations which may enhance understanding and computer-aided models of the intricacies of flatfoot, leading to better diagnosis and, ultimately, surgical treatment.

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.

Medium- to Long-term Results of Nonanatomic Spring Ligament Reconstruction Using an Allograft Tendon in Progressive Collapsing Foot Deformity With Severe Abduction Deformity

BACKGROUND

Spring ligament reconstruction (SLR) has been suggested as an adjunct to other reconstructive procedures to potentially avoid talonavicular joint fusion in progressive collapsing foot deformity (PCFD) with severe abduction deformity. Most clinical reports present short-term follow-up data and a small number of patients. The purpose of this study was to examine the medium- to long-term outcomes of an SLR using allograft tendon augmentation as part of PCFD surgical reconstruction. This study to our knowledge represents the largest number of patients and the longest follow-up to date.

METHODS

This study retrospectively reviewed 26 patients (27 feet, mean age of 61.4 years) who underwent SLR with allograft tendon as part of PCFD reconstruction. The mean follow-up of the cohort was 8 years (range, 5-13.4). Radiographic evaluation consisted of 5 parameters including talonavicular coverage angle (TNC), with the maintenance of correction being evaluated by comparing parameters from the early postoperative period (mean: 11.6 months, range, 8-17) to final follow-up. Foot and Ankle Outcome Score (FAOS) and patient satisfaction questionnaires were collected at final follow-up. Conversion to talonavicular or subtalar fusion was considered as a failure.

RESULTS

Final radiographs demonstrated successful abduction correction, with the mean TNC improving from 43.7 degrees preoperatively to 14.1 degrees postoperatively (P < .0001). All other radiographic parameters improved significantly and exhibited maintenance of the correction. All FAOS subscales showed significant improvement. Responses to the satisfaction questionnaire were received from all except 1 patient, of whom 88.5% (23/26) were satisfied with the results, 96.2% (25/26) would undergo the surgery again, and 88.5% (23/26) would recommend the surgery. Eight feet (29.6%) required painful hardware removal and 1 (3.7%) developed nonunion of the lateral column lengthening osteotomy. No patient required conversion to talonavicular or subtalar fusion.

CONCLUSION

This study demonstrates favorable medium- to long-term outcomes following PCFD reconstruction including an SLR with allograft tendon augmentation.

LEVEL OF EVIDENCE

Level IV, case series.

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.

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.

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.

Combined weightbearing CT and MRI assessment of flexible progressive collapsing foot deformity

BACKGROUND

The objective of this study was to evaluate the correlation between Weightbearing CT (WBCT) markers of pronounced peritalar subluxation (PTS) and MRI findings of soft tissue insufficiency in patients with flexible Progressive Collapsing Foot Deformity (PCFD). We hypothesized that significant correlation would be found.

METHODS

Retrospective comparative study with 54 flexible PCFD patients. WBCT and MRI variables deformity severity were evaluated, including markers of pronounced PTS, as well as soft tissue degeneration. A multiple regression analysis and partition prediction models were used to evaluate the relationship between bone alignment and soft tissue injury. P-values of less than .05 were considered significant.

RESULTS

Degeneration of the posterior tibial tendon was significantly associated with sinus tarsi impingement (p = .04). Spring ligament degeneration correlated to subtalar joint subluxation (p = .04). Talocalcaneal interosseous ligament involvement was the only one to significantly correlate to the presence of subfibular impingement (p = .02).

CONCLUSION

Our results demonstrated that WBCT markers of pronounced deformity and PTS were significantly correlated to MRI involvement of the PTT and other important restraints such as the spring and talocalcaneal interosseus ligaments.

LEVEL OF EVIDENCE

Level III, Retrospective comparative study.

The Importance of the Medial Column in Progressive Collapsing Foot Deformity: Osteotomies and Stabilization

Adult acquired flatfoot deformity is a complex pathologic condition that requires considerate and thoughtful surgical solutions. Medial column procedures are often supplemented by a medializing calcaneal osteotomy and/or a lateral column lengthening because of the complex nature of progressive collapsing foot deformity and its resultant peritalar instability. Other osteotomies and fusions include a Cotton osteotomy and first tarsometatarsal fusion.

What Are the Updates on Epidemiology of Progressive Collapsing Foot Deformity?

Progressive collapsing foot deformity is one of the most controversial topics in foot and ankle surgery. Much research has been done regarding anatomy, biomechanics, and etiology behind this complex deformity and there is interest in studying metabolic or genetic conditions that could influence the development of this multifactorial disorder. Relevant anatomy includes osseous and soft tissue structures. Several risk factors like obesity, genetics, and flat foot during childhood have been proposed in literature. It occurs 3 times more often in women, the peak incidence happening at age 55, and is more common in white, obese, diabetic, rheumatic, and hypertensive patients.

Imaging of Peritalar Instability

Undiagnosed medial ankle instability can be a prerequisite for pathogenic progression in the foot, particularly for adult acquired flatfoot deformity. With the complex anatomy in this region, and the limitations of each individual investigational method, accurately identifying peritalar instability remains a serious challenge to clinicians. Performing a thorough clinical examination aided by evaluation with advanced imaging can improve the threshold of detection for this condition and allow early proper treatment to prevent further manifestations of the instability.

Biomechanics of Medial Ankle and Peritalar Instability

The deltoid and spring ligaments are the primary restraints against pronation and valgus deformity of the foot, and in preserving the medial arch. The posterior tibial tendon has a secondary role in plantar arch maintenance, and its biomechanical stress increases considerably when other tissues fail. A thorough understanding of the anatomy and biomechanics of the deltoid-spring ligament is crucial for successful reconstruction of the tibiocalcanealnavicular ligament, hence, to restore ankle and medial peritalar stability. Although effective in correcting the deformity, tibionavicular tenodesis might be critical, as it blocks physiologic pronation of the hindfoot, which may result in dysfunction and pain.

The Failed Deltoid Ligament in the Valgus Misaligned Ankle-How to Treat?

This article deals with the treatment of a chronically failed deltoid ligament complex in the valgus misaligned ankle. This is a challenging task in every orthopedic foot and ankle surgery. Before embarking on any surgery that relates to the deltoid ligament complex, it is mandatory to analyze any underlying cause that could promote the impairment. Once this is done, it might be of value in considering anatomic reconstructions. The article provides an anatomic reconstruction technique, which should help address the problem.

Anatomy of the Deltoid-Spring Ligament Complex

A thorough knowledge of the anatomy of the deltoid and spring ligament complex is important for treatment of deformities that impact the foot and ankle. Both ligaments are interconnected, and the study of their anatomic characteristics is better performed together than in isolation. The deltoid ligament is a group of ligaments that derives its origin from the medial malleolus, and the spring ligament complex consist of a group of ligaments that connects the navicular and the sustentaculum tali of the calcaneus. They both play an important role in stabilization of the medial ankle and medial column of the foot.

Imaging Techniques for Assessment of Dynamically Unstable Sports Related Foot and Ankle Injuries

Foot and ankle instability can be seen both in acute and chronic settings, and isolating the diagnosis can be difficult. Imaging can contribute to the clinical presentation not only by identifying abnormal morphology of various supporting soft tissue structures but also by providing referring clinicians with a sense of how functionally incompetent those structures are by utilizing weight-bearing images and with comparison to the contralateral side. Loading the affected joint and visualizing changes in alignment provide clinicians with information regarding the severity of the abnormality and, therefore, how it should be managed.

Acute Deltoid Ligament Repair in Ankle Fractures

There is no consensus on whether the deltoid ligament must be repaired in ankle fractures. Recent studies have shown better early radiologic results when the deltoid ligament is repaired, but no differences in long term functional outcomes. However, there is evidence suggesting that patients with high fibular fractures or injuries with concomitant syndesmotic instability may benefit from repair. The authors recommend repairing the deltoid ligament complex in bimalleolar equivalent fractures associated with syndesmotic or gross multiligamentous instability as well as in heavier patients with greater mechanical requirements.

Indications for Deltoid and Spring Ligament Reconstruction in Progressive Collapsing Foot Deformity

RECOMMENDATION

There is evidence supporting medial soft tissue reconstruction, such as spring and deltoid ligament reconstructions, in the treatment of severe progressive collapsing foot deformity (PCFD). We recommend spring ligament reconstruction to be considered in addition to lateral column lengthening or subtalar fusion at the initial operation when those procedures have given at least 50% correction but inadequate correction of the severe flexible subluxation of the talonavicular and subtalar joints. We also recommend combined flatfoot reconstruction and deltoid reconstruction be considered as a joint sparing alternative in the presence of PCFD with valgus deformity of the ankle joint if there is 50% or more of the lateral joint space remaining.

LEVEL OF EVIDENCE

Level V, expert opinion.

Three-Dimensional Biometric Weightbearing CT Evaluation of the Operative Treatment of Adult-Acquired Flatfoot Deformity

BACKGROUND

Assessment of operative correction of adult-acquired flatfoot deformity (AAFD) has been traditionally performed by clinical evaluation and conventional radiographic imaging. Previously, a 3-dimensional biometric weightbearing computed tomography (WBCT) tool, the foot ankle offset (FAO), has been developed and validated in assessing hindfoot alignment. The purpose of this study was to investigate the role of FAO in evaluating operative deformity correction in AAFD.

METHODS

In this prospective comparative study, 19 adult patients (20 feet) with stage II (flexible) flatfoot deformity underwent preoperative and postoperative standing WBCT examination at mean 19 months (range, 6-24) after surgery. Three-dimensional coordinates of the foot tripod and center of the ankle joint were acquired by 2 independent and blinded observers. These coordinates were used to calculate the FAO using dedicated software, and subsequently compared pre- and postoperatively. The FAO is a previously validated biometric measurement that represents centering of the foot tripod as well as hindfoot alignment, with a normal mean FAO of 2.3% ± 2.9%. In addition, Patient Reported Outcomes Measurement Information System (PROMIS) clinical outcomes scores were compared pre- and postoperatively with a mean follow-up of 22.6 months (range, 14-37).

RESULTS

There was significant correction of flatfoot deformity from a mean preoperative FAO of 9.8% to a mean postoperative value of 1.3% (P < .001). Additionally, there was statistically significant improvement in all PROMIS domains (P < .05), except depression, at an average follow-up of 22.6 months. Spring ligament reconstruction was the only procedure associated with a significant correction in FAO (P = .0064).

CONCLUSION

The FAO was a reliable and sensitive tool that was used to evaluate preoperative deformity as well as postoperative correction, with patients demonstrating both significant improvement in FAO as well as patient-reported outcomes. These findings demonstrate the role for biometric 3-dimensional WBCT imaging in assessing operative correction after flatfoot reconstruction, as well as the potential role for operative planning to address preoperative deformity.

LEVEL OF EVIDENCE

Level II, prospective comparative study.

Advanced Ankle and Foot Sonoanatomy: Imaging Beyond the Basics

Ankle/foot pain is a common complaint encountered in clinical practice. Currently, due to the complex anatomy, the diagnosis and management of the underlying musculoskeletal disorders are extremely challenging. Nowadays, high-resolution ultrasound has emerged as the first-line tool to evaluate musculoskeletal disorders. There have been several existing protocols describing the fundamental sonoanatomy of ankle/foot joints. However, there are certain anatomic structures (e.g., Lisfranc ligament complex or Baxter nerve) which are also clinically important. As they are rarely elaborated in the available literature, a comprehensive review is necessary. In this regard, the present article aims to brief the regional anatomy, illustrate the scanning techniques, and emphasize the clinical relevance of the ankle/foot region.