Subtalar arthrography in acute injuries of the calcaneofibular ligament

Current Concepts on Subtalar Instability

Subtalar instability remains a topic of debate, and its precise cause is still unknown. The mechanism of injury and clinical symptoms of ankle and subtalar instabilities largely overlap, resulting in many cases of isolated or combined subtalar instability that are often misdiagnosed. Neglecting the subtalar instability may lead to failure of conservative or surgical treatment and result in chronic ankle instability. Understanding the accurate anatomy and biomechanics of the subtalar joint, their interplay, and the contributions of the different subtalar soft tissue structures is fundamental to correctly diagnose and manage subtalar instability. An accurate diagnosis is crucial to correctly identify those patients with instability who may require conservative or surgical treatment. Many different nonsurgical and surgical approaches have been proposed to manage combined or isolated subtalar instability, and the clinician should be aware of available treatment options to make an informed decision. In this current concepts narrative review, we provide a comprehensive overview of the current knowledge on the anatomy, biomechanics, clinical and imaging diagnosis, nonsurgical and surgical treatment options, and outcomes after subtalar instability treatment.

The Location of the Fibular Tunnel for Anatomically Accurate Reconstruction of the Lateral Ankle Ligament: A Cadaveric Study

We aimed to describe the location of fibular footprint of each anterior talofibular ligament (ATFL) and calcaneofibular ligament (CFL), as well as their common origin in relation to bony landmarks of the fibula in order to determine the location of the fibular tunnel. In 105 ankle specimens, the center of the footprints of the ATFL and CFL (cATFL and cCFL, respectively) and the intersection point of their origin (intATFL-CFL) were investigated, and the distances from selected bony landmarks (the articular tip (AT) and the inferior tip (IT) of the fibula) were measured. Forty-two (40%) specimens had single-bundle ATFL, and 63 (60%) had double-bundle patterns. The distance between intATFL-CFL and IT was 12.0 ± 2.5 mm, and a significant difference was observed between the two groups (p = 0.001). Moreover, the ratio of the intATFL-CFL location based on the anterior fibular border for all cadavers was 0.386. The present study suggests a reference ratio that can help surgeons locate the fibular tunnel for a more anatomically accurate reconstruction of the lateral ankle ligament. Also, it may be necessary to make a difference in the location of the fibular tunnel according to the number of ATFL bundles during surgery.

Currently used imaging options cannot accurately predict subtalar joint instability

PURPOSE

To give a systematic overview of current diagnostic imaging options and surgical treatment for chronic subtalar joint instability.

METHODS

A systematic literature search across the following sources was performed: PubMed, ScienceDirect, and SpringerLink. Twenty-three imaging studies and 19 outcome studies were included. The Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS 2) tool was used to assess the methodologic quality of the imaging articles, while the modified Coleman Score was used to assess the methodologic quality of the outcome studies.

RESULTS

Conventional radiographs were most frequently used to assess chronic subtalar joint instability. Talar tilt, anterior talar translation, and subtalar tilt were the three most commonly used measurement methods. Surgery often included calcaneofibular ligament reconstruction.

CONCLUSION

Current imaging options do not reliably predict subtalar joint instability. Distinction between chronic lateral ankle instability and subtalar joint instability remains challenging. Recognition of subtalar joint instability as an identifiable and treatable cause of ankle pain requires vigilant clinical investigation.

LEVEL OF EVIDENCE

Systematic Review of Level III and Level IV Studies, Level IV.

Independent Attachment of Lateral Ankle Ligaments: Anterior Talofibular and Calcaneofibular Ligaments - A Cadaveric Study

Anatomic knowledge of lateral ligaments around the lateral malleolus is important for repair or reconstruction of ankle instability. The detailed structure of the connective fibers between the anterior talofibular ligament (ATFL) and the calcaneofibular ligament (CFL) is unknown. To clarify the anatomic structure of ATFL and CFL and the connective fiber between the 2 ligaments, the lateral ligament was dissected in 60 ankles of formalin-fixed cadavers, and the distance was measured between bony landmarks and fibular attachment of ATFL and CFL using a digital caliper. All ankles had connective fibers between ATFL and CFL. The structure of connective fibers consisted of a thin fiber above the surface layer of ATFL and CFL; it comprised thin fibrils of the surface layer covering the lower part of ATFL and the front part of CFL. Both ATFL and CFL were independent fibers, and both attachments of the fibula were isolated. Single bands of ATFL were noted in 14 of 60 (23.3%) ankles, double bands that divided the superior and inferior bands were observed in 42 of 60 (70.0%) ankles, and multiple bands were observed in 4 of 60 (6.7%) ankles. A cord-like and a flat and fanning type of CFL was noted in 22 (36.7%) and 38 (63.3%) of the 60 ankles, respectively. Distances between ATFL/CFL and articular and inferior tips of the fibula were 4.3 ± 1.1 mm/7.6 ± 1.6 mm and 14.3 ± 1.9 mm/7.4 ± 1.7 mm, respectively (mean ± standard deviation). The results of this study suggest that knowledge of more anatomic structures of ATFL, CFL, and connective fiber will be beneficial for surgeons in the repair or reconstruction of the lateral ligament of the ankle.

Anatomic validation of the lateral malleolus as a cutaneous marker for the distal insertion of the calcaneofibular ligament

PURPOSE

An anatomic study was performed to confirm whether the lateral malleolus could serve as a simple and reproducible anatomic reference for the distal insertion of the calcaneofibular ligament (CFL).

METHODS

Dissection was performed after placement of a Kirschner wire to simulate the calcaneal tunnel for the distal insertion of the CFL. The skin was penetrated 1 cm distal and posterior to the tip of the lateral malleolus. The main information recorded was the distance from the Kirschner wire to the centre of the distal insertion of the CFL. Other elements were noted (characteristics of the CFL, distance between the distal insertion of the CFL-peroneal tubercle, nerve or tendon injuries).

RESULTS

Thirty ankles were dissected. The mean distance from the Kirschner wire to the centre of the distal insertion of the CFL was 2.4 ± 1.8 mm. Only one case of peroneal injury was noted. The sural nerve was usually located a mean 1.8 ± 1.1 mm from the Kirschner wire. The posterior tibial vascular pedicle was a mean 27.8 ± 3.5 mm from the point of exit of the Kirschner wire.

CONCLUSION

Using the lateral malleolus as the cutaneous reference for the distal insertion of the CFL seems to be more reliable than the pure arthroscopic technique. This study describes a percutaneous technique to obtain a calcaneal tunnel for distal insertion of the CFL. The sural nerve is at the greatest risk of injury with this technique and requires careful subcutaneous incision to prevent injury. This new percutaneous technique is less invasive than a purely arthroscopic technique and more accurately identifies the location of the tunnel. It can be used to do calcaneal tunnel in clinical practice during anatomic ligament reconstruction for chronic ankle instability.

Recent Developments in the Treatment of Ankle and Subtalar Instability

It was nearly a centenary ago that severe ankle sprain was recognized as an injury of the ankle ligament(s). With the recent technological advances and tools in imaging and surgical procedures, the management of ankle sprains - including subtalar injuries - has drastically improved. The repair or reconstruction of ankle ligaments is getting more anatomical and less invasive than previously. More specifically, ligamentous reconstruction with tendon graft has been the gold standard in the management of severely damaged ligament, however, it does not reproduce the original ultrastructure of the ankle ligaments. The anatomical ligament structure of a ligament comprises a ligament with enthesis at both ends and the structure should also exhibit proprioceptive function. To date, it remains impossible to reconstruct a functionally intact and anatomical ligament. Cooperation of the regenerative medicine and surgical technology in expected to improve reconstructions of the ankle ligament, however, we need more time to develop a technology in reproducing the ideal ligament complex.

Diagnostic validity of alternative manual stress radiographic technique detecting subtalar instability with concomitant ankle instability

PURPOSE

To incorporate a diagnostic technique for measuring subtalar motion, namely "talar rotation", into the manual supination-anterior drawer stress radiographs for evaluation of the severity of rotational instability, and to determine its clinical relevance.

METHODS

Sixty-six patients with combined injuries of the anterior talofibular (ATFL) and calcaneofibular ligament (CFL) underwent three bilateral manual stress radiographs, and mean increments of anterior talar translation (mm), talar tilt (°), and talar rotation (%) in the injured ankle compared to the normal opposite side were measured with the technique. Intraobserver and interobserver reliability of each measure was assessed, and the difference in the degree of increments was compared according to the presence of additional cervical ligament insufficiency.

RESULTS

Ankle stress radiographic intraobserver and interobserver agreement was ICC = 0.91 and 0.82 for talar rotation (%), ICC = 0.64 and 0.51 for anterior talar translation, and ICC = 0.78 and 0.71 for talar tilt angle, respectively. In group 2 including patients with combined injuries of the ATFL and CFL along with additional cervical ligament insufficiency, a significantly higher increment of talar rotation, mean 6.4% (SD 3.4%), was observed compared to that of talar rotation, mean 4.1% (SD 2.7 ), in the other group (group 1) with an intact cervical ligament (p < 0.001).

CONCLUSIONS

A new comprehensive stress radiographic technique for diagnosis of chronic lateral ankle instability presented in this study might be a reliable and representable measurement tool to assess additional injury or instability of the subtalar joint.

LEVEL OF EVIDENCE

Prospective cohort study, Level II.

Imaging of the subtalar joint

Imaging of the subtalar joint can be challenging because of its complex planar anatomy. This article reviews the anatomy and common anatomic variants as seen with different imaging techniques. Although radiography remains the initial mode of imaging, computed tomography and MRI are frequently needed to better delineate the joint anatomy and improve the sensitivity and the specificity of detection of joint pathology. A short review of arthrographic techniques and various examples of imaging of common pathology involving this joint are also included.

Subtalar instability

Subtalar instability is a common clinical entity. Clinicians should have a high index of suspicion of this diagnosis in patients who have been diagnosed with chronic lateral ankle instability but have failed standard management and have continued pain in the sinus tarsi. As with ankle instability, nonoperative management is the initial mainstay of treatment. Operative management includes ligamentous reconstruction of key lateral stabilizers of the subtalar joint. Future research on this subject should be focused at improving diagnosis and recognition of this entity.

Upper ankle ligament rupture and long term problems in a patient with Ehlers Danlos Syndrome — a case report

Rupture of the upper ankle joint ligaments is a common injury. Therapy in patients with Ehlers Danlos Syndrome (EDS) is a challenge due to the autosomal-dominant collagenopathy. Therapeutic recommendations and long term results in treatment of patients with EDS are rare. Therefore uncertainty exists. We present a case of clinical and radiologic long term results after ligament rupture of the upper ankle joint in a patient with EDS. A literature review tries to reveal current therapeutic strategies in patients with EDS.

Adjacent tissue involvement of acute inflammatory ankle arthritis on magnetic resonance imaging findings

PURPOSE

The ankle joint and surrounding subtalar joint have several tendons in close proximity. This study was performed to investigate the concurrent adjacent tissue involvement on MRI findings when the surgical treatment is considered for an acute inflammatory arthritis of the ankle joint.

METHODS

Consecutive patients with acute inflammatory ankle arthritis who visited the emergency room and underwent MRI were included. After interobserver reliability testing of MRI findings, adjacent tissue involvement in the acute inflammatory ankle arthritis were evaluated including flexor hallucis longus (FHL), flexor digitorum longus (FDL), tibialis posterior (TP), peroneus longus (PL), peroneus brevis (PB), extensor digitorum longus (EDL), tibialis anterior (Tib Ant), extensor hallucis longus (EHL), subtalar joint, talus, tibia, and calcaneus.

RESULTS

Twenty-five patients (mean age 57.8 years; 16 males and nine females) were included. Of the 25 patients, 23 showed FHL involvement, 21 FDL, 21 TP, 15 PL, 15 PB, three EDL, 21 subtalar joint, six talus, six tibia, and five calcaneus on MR images. No Tib Ant or EHL involvement was observed on MR findings in acute inflammatory ankle arthritis.

CONCLUSIONS

Patients with acute inflammatory ankle arthritis showed frequent concomitant surrounding tissue involvement on MRI, which included FHL, FDL, TP, and subtalar joint. This needs to be considered when surgical drainage is planned for acute inflammatory ankle arthritis.

Subtalar instability: diagnosis and treatment

Subtalar instability is challenging to diagnose. It rarely follows a complete subtalar dislocation, an event more likely to result in subtalar pain, stiffness, and arthritis. By history, subtalar instability can be suggested by the patient’s feeling of ankle instability, easy “rolling over,” and a need to look at the ground constantly when walking. Clinical measures for inversion and eversion do not accurately reflect isolated subtalar motion, as soft tissue and other joint motion confound the examination. Stress radiographs have high false positive rates. Magnetic resonance imaging can show injured or disorganized ligaments suggestive of recurrent subtalar strain, but are not dynamic studies and cannot alone diagnose instability. Operative treatment, when elected, should focus on determining the source of the problem. Generally direct repair of the lateral ligaments is sufficient. Bony malalignment should always be considered especially in the setting when previous ligament reconstruction has failed.

Chronic ankle and subtalar joint instability in the athlete

Chronic ankle and subtalar joint (STJ) instability is a common clinical entity and the physician must be able to determine the exact pathologic condition for proper treatment. There are many diagnostic techniques that can be used to evaluate the ankle joint and STJ. These diagnostic techniques do not take the place of a proper patient history taking. Appropriate and aggressive rehabilitation should be attempted in all cases of chronic ankle and subtalar instability before electing surgical reconstruction.

Accuracy of sonographically guided posterior subtalar joint injections: comparison of 3 techniques

OBJECTIVE

The primary purpose of this investigation was to determine the accuracy of 3 different sonographically guided posterior subtalar joint (PSTJ) injection techniques in an unembalmed cadaveric model.

METHODS

A single experienced examiner injected the PSTJs of 12 unembalmed cadaveric ankle-foot specimens using the anterolateral, posterolateral, and posteromedial approaches. The injection order for each specimen was randomized, and each technique was completed with a different-color diluted latex solution. Coinvestigators blinded to the injection technique dissected each specimen and graded the colored latex location as accurate (in the PSTJ), accurate with overflow (within the PSTJ but also in other regions), or inaccurate (no latex in the joint).

RESULTS

All 3 sonographically guided PSTJ injection approaches accurately placed latex into the PSTJ (100% accuracy). Latex was also found in adjacent regions in 19.4% (7 of 36) of injections: 8.3% (3 of 36) within the tibiotalar joint, 8.3% (3 of 36) in the peroneal (fibularis) tendon sheath, and 2.8% (1 of 36) in the flexor hallucis longus tendon sheath. The anterolateral approach placed latex outside the PSTJ 25% of the time (3 of 12 injections: 1 tibiotalar and 2 peroneal [fibularis] sheath), the posterolateral approach 25% of the time (3 of 12 injections: 1 tibiotalar, 1 peroneal [fibularis] sheath, and 1 flexor hallucis longus tendon sheath), and the posteromedial approach 8.3% of the time (1 tibiotalar).

CONCLUSIONS

This cadaveric investigation suggests that all 3 sonographically guided PSTJ techniques may be used to access the PSTJ with a high degree of accuracy. Clinicians should consider sonographically guided PSTJ injections as a favorable alternative to fluoroscopy and computed tomographic guidance when diagnostic or therapeutic image-guided PSTJ injections are indicated.

Chondral injuries of the ankle with recurrent lateral instability: an arthroscopic study

BACKGROUND

Prolonged lateral instability of the ankle after ligament injury has been believed to be a major cause of osteoarthritis of the ankle, yet the rate of development of osteoarthritis of the ankle is relatively low. Clarifying the relationship between patient factors and chondral damage of the ankle with prolonged instability is essential to identify the important risk factors underlying osteoarthritis of the ankle.

METHODS

Arthroscopic examination was performed to assess the condition of the articular cartilage in a series of patients with prolonged lateral instability of the ankle. There were ninety-three patients with ninety-nine involved ankles. Their mean age was 28.7 years (range, fifteen to fifty-nine years). The relationships between the severity of the chondral damage and patient factors, the number and combination of torn ligaments, and mechanical instability and alignment of the ankle mortise were studied.

RESULTS

Twenty-three ankles were classified as grade 0 (normal cartilage); thirty-five, as grade 1 (superficial softening, fibrillation, or fissuring of the cartilage); twenty-four, as grade 2 (a cartilage defect without exposure of the subchondral bone); and seventeen, as grade 3 (exposure of the subchondral bone). Patient age, the talar tilt angle, and varus inclination of the ankle plafond were significantly associated with more severe chondral changes.

CONCLUSIONS

Patient age, the talar tilt angle, and varus inclination of the ankle are risk factors for severe chondral damage of the ankle in patients with a prolonged history of lateral ankle instability.

Management of acute and chronic ankle instability

Acute lateral ankle ligament injuries are common. If left untreated, they can result in chronic instability. Nonsurgical measures, including functional rehabilitation, are the management methods of choice for acute injuries, with surgical intervention reserved for high-demand athletes. Chronic lateral ankle instability is multifactorial. Failed nonsurgical management after appropriate rehabilitation is an indication for surgery. Of the many surgical options available, anatomic repair of the anterior talofibular and calcaneofibular ligaments is recommended when the quality of the ruptured ligaments permits. Anatomic reconstruction with autograft or allograft should be performed when the ruptured ligaments are attenuated. Ankle arthroscopy is an important adjunct to ligamentous repair and should be performed at the time of repair to identify and address intra-articular conditions associated with chronic ankle instability. Tenodesis procedures are not recommended because they may disturb ankle and hindfoot biomechanics.

Comparative results of conservative treatments for isolated anterior talofibular ligament (ATFL) injury and injury to both the ATFL and calcaneofibular ligament of the ankle as assessed by subtalar arthrography

BACKGROUND

There have been no reports describing the results of conservative treatment of acute lateral ligament injury of the ankle in detail in terms of the severity of the injury, and the results of conservative treatment for injury with severe instability are still controversial. The purpose of this study was to assess the results of nonoperative treatment of acute lateral ligament injury according to its severity.

METHODS

Fifty-five consecutive acute lateral ankle ligament injuries in 54 patients who were treated nonoperatively were followed up as a prospective study. Twenty-seven were male patients and 27 were female patients; the average age was 23.9 years (12-55 years). The patients were divided into two groups according to the extent of the ligament injury: patients with an isolated injury of the anterior talofibular ligament and those with combined injuries of the anterior talofibular ligament and the calcaneofibular ligament. In addition to the routine examinations for inversion ankle sprain, subtalar arthrography was mainly used to assess the condition of the calcaneofibular ligament. The arthrography was performed an average of 3.5 days after the injury (0-5 days).

RESULTS

Fifty-five ankles of patients who were treated nonoperatively according to the same protocol were included in this study, and were followed up for an average of 5.0 years (37-86 months). At the time of the final follow-up, 22 of 25 (88%) ankles with an isolated injury to the anterior talofibular ligament were asymptomatic; in contrast, only 9 of 30 (30%) ankles with combined injuries of the anterior talofibular and calcaneofibular ligament were asymptomatic. The average American Orthopaedic Foot and Ankle Society score of the isolated injuries was 97.8 points, in contrast to 92.4 points for the combined injuries.

CONCLUSIONS

The results of nonoperative treatment with 1 week immobilization followed by a functional brace were excellent in patients with an isolated injury of the anterior talofibular ligament, but were unsatisfactory in those with combined injuries of the anterior talofibular and calcaneofibular ligaments.

The effect of ankle injury on subtalar motion

BACKGROUND

Injuries to the medial and lateral ankle ligaments have been implicated in subtalar joint instability. Lateral injury increased subtalar joint varus and anterior translation, while deltoid injury increased external rotation and valgus in studies using static, non-physiologic testing.

METHODS

The current study employed a physiologically accurate ankle model using phasic force-couples attached to the muscle-tendon units to reproduce ankle motion. Six-degree-of-freedom kinematics of the tibia, talus, and calcaneus were measured using a VICON motion analysis system under the following experimental conditions: 1) intact ligaments 2) complete lateral ligament injury with subsequent repair, 3) superficial deltoid injury with subsequent repair, and 4) deep deltoid injury without repair in eight harvested lower extremities. Statistical analysis was by repeated measures analyses of variance.

RESULTS

At heel-strike, the subtalar joint is in internal rotation, dorsiflexion, and varus. As the leg progresses to foot-flat, there is external rotation, plantarflexion, and valgus rotation. From foot-flat to heel-rise, there is little subtalar joint motion, while at toe-off, there is slight internal rotation, dorsiflexion, and varus rotation. The total rotations amounted to 9.0 degrees (SD 5.0 degrees) external rotation, 6.1 degrees (SD 2.5 degrees) plantarflexion, and 7.8 degrees (SD 5.5 degrees) valgus. Disruption of the superficial deltoid increased plantarflexion (p < .001) and valgus (p < .05). The additional lateral injury increased both external rotation (p < .001) and valgus (p < .02). Lateral injury alone had no significant effect on subtalar joint motion.

CONCLUSION

Unlike most previous reports, this study showed no significant influence of isolated lateral ankle injury on subtalar joint motion, probably because the current study examined subtalar joint motion under physiologic loading and motion rather than by static stress testing. This calls into question the relevance of static stress testing to the in situ function of the subtalar joint. The increased external rotation and valgus seen with deltoid injury in the current study is consistent with previous reports.

Subtalar arthrodesis

A satisfactory outcome after isolated subtalar joint arthrodesis is dependent on proper patient selection, understanding the pathology and indications, and choosing the appropriate operative technique. Performing a thorough history and physical examination will assist in this process. Ancillary tests, including radiographs and advanced imaging, should be obtained to reinforce the surgeon's suspicions and to aid in the proper surgical planning for the patient. Also, a proper postoperative protocol should be used to allow for adequate healing, and,thus, optimize functional outcome.

Achilles tendon rupture associated with injury of the calcaneofibular ligament

A 49-year-old man collided against an infielder when he slid into second base during a recreational baseball game. He was unable to continue in the game due to diffuse pain and swelling of his hindfoot. A rupture of the Achilles tendon was diagnosed incidentally on palpation and observation of a positive Thompson's squeeze test. Subcutaneous hemorrhage at the lateral aspect of the heel and a small bone fragment under the lateral malleolus on an anteroposterior plain radiograph indicated a fracture of the calcaneal wall. At surgery, a complete rupture of the Achilles tendon and an avulsion of the calcaneofibular ligament from the calcaneal wall were seen. Both injuries were surgically repaired, and the patient subsequently did well. The mechanism of injury was thought to be impact hyperdorsiflexion of the ankle with rupture of the Achilles tendon accompanied by an inversion injury. Using a literature search, it was found that this combination of injuries has not been previously reported.

Reconstruction of the lateral ankle ligaments with bone-patellar tendon graft in patients with chronic ankle instability: a preliminary report

BACKGROUND

Unsatisfactory long-term results have been reported after use of a Broström repair for patients with chronic ankle ligament insufficiency.

HYPOTHESIS

Repair or reconstruction of both the anterior talofibular and calcaneofibular ligaments is essential for normal kinematics of the ankle-hindfoot.

STUDY DESIGN

Case series.

METHODS

Thirteen patients with chronic instability of the ankle were found at operation to have injuries of both the anterior talofibular and calcaneofibular ligaments, with a lack of healthy ligament margins suitable for suturing. Reconstruction of the ligaments was performed with bone-patellar tendon graft. The score devised by Good et al. was used to assess the patients' clinical condition before the operation and at final follow-up.

RESULTS

Before the operation, six patients had a grade 3 clinical condition and seven had a grade 4 condition. At a mean follow-up of 26.5 months, all patients had a grade 1 condition. The average talar tilt of the patients was improved from 18.4 degrees +/- 5.5 degrees to 4.9 degrees +/- 2.6 degrees, and the average anterior drawer sign was improved from 9.1 +/- 2.6 mm to 5.8 +/- 1.6 mm.

CONCLUSION

In cases of combined injuries, short-term results of reconstruction of the anterior talofibular and calcaneofibular ligaments using bone-split patellar tendon graft were good, with a low frequency of complications.

Ligamentous injuries about the ankle and subtalar joints

Ligamentous injuries at the ankle and subtalar joint range from simple sprains to severe talar dislocations. While lateral ankle sprains are among the most frequently encountered injuries and do not pose a greater diagnostic problem, the surgeon must be suspicious not to overlook associated ligamentous injuries at the subtalar and midtarsal level that may result in chronic painful conditions. Syndesmotic instabilities with or without ankle fractures must be assessed carefully and treated properly, since these are prearthrotic conditions. In the treatment of chronic ankle or subtalar instability tenodeses provide mechanical stability while reducing subtalar mobility. Anatomic reconstruction methods therefore should be considered for both conditions.