The resistance to failure of spring ligament reconstruction

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.

Medial arch instability/internal foot overload association with non-insertional Achilles tendinopathy and the 'Zone of Conflict Theory'

BACKGROUND

Non insertional Achilles tendinopathy [AT] is a degenerative condition that is prevalent in runners. 30% have no preceding history and many runners do not develop AT. Overuse, pronation, and compromised blood supply are hypothesised as causal. The exact precipitant is still unknown. The link between medial arch instability and AT has not been made. The purpose of this study was to investigate the association between spring ligament (SL) laxity and first ray (FRI) instability, and the presence of (AT).

METHODS

Ethical approval was obtained. Patients were identified from hospital databases for unilateral AT, allowing the opposite unaffected foot to be used as an internal control. SL laxity was measured using the lateral translation score and FRI was measured using a modified digital Klauemeter. Ultrasound was used to assess the tendoachilles [TA] in affected vs unaffected legs.

RESULTS

17 patients were recruited with a mean age of 55.6 and mean body mass index (BMI) of 33.3. The average symptom duration was 3.62 years. There were 12 left feet and 5 right feet. There was no statistical difference in dorsiflexion angles for the TA or the gastrocnemius. All Beighton scores < 5. Lateral translation scores, FRI scores and TA thickness was significantly greater in AT feet [p < 0.05]. More affected feet had Tibialis posterior tendon pain (TP) [p < 0.05].

CONCLUSIONS

Feet with AT exhibit higher lateral translation scores and greater FRI compared to healthy feet, and combined with previous literature evidence, suggests alteration of the subtalar axis alters force moments that may lead to an intrinsic overload of the TA, when the foot enters a "zone of conflict". Medial arch instability, in particular SL laxity and FRI, may contribute to the development of non-insertional AT and treatment of this with early arch support may prevent progressive degeneration.

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.

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.

Comparison of each bundle of the spring ligament complex between the standing and supine positions: A multiposture magnetic resonance imaging study

BACKGROUND

The spring ligament complex (SLC) supports the medial longitudinal arch of the foot, particularly in standing. We evaluated posture-related changes in the thickness and length of the three SLC bundles and their histology.

METHODS

The thickness and length of the supramedial calcaneonavicular ligament (smCNL), medioplantar oblique calcaneonavicular ligament (mpoCNL), and inferoplantar calcaneonavicular ligament (iplCNL) were measured in the supine and standing positions, using a multiposture magnetic resonance imaging system, in 72 healthy adult feet. Histological examination was performed for 10 feet from five cadavers.

RESULTS

The smCNL thickness decreased and its length increased from the supine to the standing position (P < 0.001); no other posture-related effects were noted. Histologically, smCNL fibers overlapped along multiple directions while mpoCNL and iplCNL, fibers were oriented horizontally along the longitudinal axis and vertically along the short axis, respectively.

CONCLUSION

The complex, multidirectional, orientation of the smCNL allows an adaptive response to changes in loading.

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.

How does the postoperative medial arch height influence the patient reported outcomes of stage Ⅱ acquired adult flatfoot deformity?

BACKGROUND

This study aimed to assess how the postoperative medial arch height influenced postoperative patient-reported clinical outcomes after surgery for stage Ⅱ acquired adult flatfoot deformity.

METHODS

A total of 30 feet of 30 patients (7 males, 23 females) who underwent surgery for stage Ⅱ acquired adult flatfoot deformity and could be followed up for at least 2 years were included. The average age at surgery was 60.0 (standard deviation, 13.0) years, and the average follow-up period was 40 (standard deviation, 15.4) months. Among them, 16 patients underwent lateral column lengthening and 14 patients did not. Patient-reported clinical outcomes were evaluated using the Self-Administered Foot Evaluation Questionnaire. Radiographic alignment was evaluated by the talonavicular coverage angle, lateral talo-1st metatarsal angle, medial cuneiform height, medial cuneiform to 5th metatarsal height, and calcaneal pitch. The correlation between postoperative Self-Administered Foot Evaluation Questionnaire and radiographic alignment was assessed with Pearson's correlation analysis.

RESULTS

Self-Administered Foot Evaluation Questionnaire and radiographic alignment significantly improved postoperatively in all patients (P < 0.0001). In patients with severe deformity who needed lateral column lengthening, lateral talo-1st metatarsal angle was negatively and medial cuneiform to 5th metatarsal height was positively correlated with physical functioning Self-Administered Foot Evaluation Questionnaire subscales (r = -0.56 and 0.55), and medial cuneiform height was positively correlated with physical functioning, social functioning and general health Self-Administered Foot Evaluation Questionnaire subscales (r = 0.70, 0.55 and 0.73, respectively).

CONCLUSION

Postoperative medial arch height could influence physical functioning, social functioning, and general health in patients with severe stage II adult-acquired flatfoot deformity.

Augmented Spring Ligament Repair in Pes Planovalgus Reconstruction

Patients with pes planovalgus deformity often have coexisting spring ligament pathology. A primary repair of the ligament may fail during weightbearing due to chronic degeneration of the ligamentous tissue. Augmentation with a suture tape has been suggested to strengthen the repair. Limited data exist regarding flatfoot reconstruction with augmented spring ligament repair using a suture tape. This is a review of 57 consecutive patients who had flatfoot reconstruction with concomitant spring ligament augmented repair between July 2014 and August 2017. Weightbearing radiographic parameters were obtained preoperatively and compared to radiographs at an average time of 62 ± 46.5 (range 20-220) weeks postoperative. Significant improvements were seen in the radiographic parameters evaluated. Five patients had subsequent operations including one deep infection, 2 hardware removals remote to the spring ligament augmentation, 1 ankle arthrodesis, and 1 triple arthrodesis. Concomitant spring ligament repair augmented with a suture tape was a safe procedure that contributed to radiographic correction in a consecutive series of 57 patients undergoing flatfoot deformity correction.

Spring ligament insufficiency and hallux valgus as an independent risk factors for first ray instability

INTRODUCTION

First ray instability (FRI) arising from failed plantar/interosseous ligaments is strongly associated with planovalgus, leading to synovitis and deformity. Our hypothesis is that proximal spring ligament insufficiency (SLI) drives secondary FRI in the absence of hallux valgus (HV) and may be an independent risk factor.

METHODS

Patients with FRI, screened by Klaue's test, were recruited. Patients' normal contralateral feet with previous radiographs were included as controls. First ray dorsal translation was measured with a digital Klauemeter. Spring ligament integrity was assessed using lateral translation distance as an indirect measure of spring ligament strain. Intermetatarsal angle and hallux valgus angle were recorded to classify the severity of HV.

RESULTS

Seventy feet included, 54 had symptomatic FRI and 16 were asymptomatic contralateral feet included as control. Twenty-three feet had moderate/severe HV and 47 had mild/normal HV. Moderate/severe HV was associated with FRI (OR, 10.31; p = 0.029). Forty-five feet with SLI had a strong association with FRI (OR, 100.7; p < 0.0001). SLI without moderate/severe HV was the most prevalent group (31/54), followed by SLI with moderate/severe HV, 29.63% (16/54). Moderate/severe HV without SLI was prevalent in 11.1% (6/54) and 1.85% (1/54) had no SLI or moderate/severe HV. In a multivariate logistic regression analysis model, both SLI and severe/moderate HV were independent predictors of FRI.

CONCLUSION

This is the first study that links SLI and HV as independent risk factors to FRI. 98.15% of FRI can be attributed to SLI, HV or both. First ray instability may allude to the strong presence of spring ligament insufficiency in the absence of hallux valgus.

LEVEL OF EVIDENCE

Level III, retrospective cohort study.

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.

High incidence of spring ligament laxity in ankle fractures with complete deltoid ruptures and secondary first ray instability

AIMS

To assess the incidence of spring ligament failure in patients who have complete deltoid ruptures.

PATIENTS AND METHODS

The authors retrospectively analysed ankle fractures in our trauma database from January 2015 to January 2019. 61 patients who sustained ankle fractures with complete deltoid ligament ruptures based on an AP ankle radiographs with increased medial joint space were identified. 25 patients attended clinic for assessment. Of these, 5 were found to have gross planovalgus with pre-existing spring ligament laxity in the uninjured control foot and these were excluded from the analysis. 20 patients were assessed for spring ligament failure /laxity. For each patient, the uninjured foot was used as the control.

RESULTS

The TMT instability score and the lateral translation score showed statistically significant increases in the injured compared to the uninjured foot. The ratio of increase in both TMT instability and lateral translation scores (strain) in the injured versus the uninjured foot was assessed. A strong correlation (+0.62 pearson correlation coefficient) was found between the two ratios.

CONCLUSION

All 20 patients showed increased spring ligament laxity and 19 patients showed increased TMT instability. Our results show that with complete deltoid rupture, there is likely greater disruption of the medial ligamentous structures of the foot than previously recognised. The degree of increase in the spring ligament strain also correlates with the degree of strain at the plantar TMT joint ligaments, and thus first ray instability. This finding has significant implications for the long-term assessment and management of ankle fractures involving complete deltoid disruption. Early intervention with orthotics in this cohort may prevent progressive destabilisation of the midfoot and the first ray. This evolving understanding may lead to the prospect of earlier surgical intervention to reconstitute the integrity of the spring ligament and protect the foot progressing to stage 2 AAFD.

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.

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.

Finite element analysis of secondary effect of midfoot fusions on the spring ligament in the management of adult acquired flatfoot

BACKGROUND

Surgical treatment of adult acquired flatfoot deformity can involve arthrodesis of the midfoot to stabilize the medial column. Few experimental studies have assessed the biomechanical effects of these fusions, because of the difficulty of measuring these parameters in cadavers. Our objective was to quantify the biomechanical stress caused by various types of midfoot arthrodesis on the Spring ligament. To date this is not known.

METHODS

An innovative finite element model was used to evaluate flatfoot scenarios treated with various combinations of midfoot arthrodesis. All the bones, cartilages and tissues related to adult acquired flatfoot deformity were included, respecting their biomechanical characteristics. The stress changes on the Spring ligament were quantified. Both foot arch lengthening and falling were measured for each of the midfoot arthrodeses evaluated.

FINDINGS

Arthrodesis performed for stabilization of the talonavicular joint leads to a higher decrease in stress on the Spring ligament. Talonavicular fusion generated a Spring ligament stress decrease of about 61% with respect to the reference case (without any fusion). However, fusing the naviculocuneiform joints leads to an increase in the stress on the Spring ligament.

INTERPRETATION

This important finding has been unknown to date. We advocate caution regarding fusion of the naviculocuneiform joint as it leads to increased stresses across the Spring ligament and therefore accelerates the development of planovalgus.

InternalBrace has biomechanical properties comparable to suture button but less rigid than screw in ligamentous lisfranc model

Purpose

The aim of this study was to investigate the biomechanical properties of the InternalBrace for lisfranc injuries.

Methods

A Sawbone model was developed comparing screw, suture button and InternalBrace.

Results

When loaded in axial tension at 0.5 mm/s, the screw was stiffest (2,240 N/mm), while the InternalBrace (200 N/mm) was stiffer than the suture button (133 N/mm). Cyclic loading with 10,000 cycles of 69 N, 138 N, and 207 N showed the InternalBrace maintained stiffness, but fatigued earlier than the suture button.

Conclusion

The mechanical properties of the InternalBrace support clinical use, but further studies are needed regarding early weight bearing.

Long-term follow-up of patients undergoing tibialis posterior transfer: Is acquired pes planus a complication?

In this retrospective study, a series of 10 elective patients treated with transfer of the tibialis posterior (TP) tendon for pes cavus and drop foot are described. Since TP transfer completely subtracts the role of this tendon, this cohort of patients provides an opportunity to examine the consequences of tibialis posterior (TP) deficiency. After a mean follow up period of 44.7 months, only one patient showed evidence of strain in the spring ligament but none of the patients in this series developed clinical or radiological evidence of planovalgus deformity. The authors conclude that planovalgus deformity is not an inevitable sequelae of TP Tendon transfer and that established theory underestimates the role of static soft tissue restraints such as spring ligament in hindfoot stability.