Hallux saltans due to stenosing tenosynovitis of flexor hallucis longus: dynamic sonography and arthroscopic findings

Intermittent flexor hallucis longus dislocation: ultrasound findings

We report a case of intermittent dislocation of the flexor hallucis longus at its passage in the retro-malleolar area, related to a post-traumatic detachment of the retrotalar pulley from the medial tubercle of the talus. High-resolution ultrasound depicted the anterior dislocation of the tendon during dynamic stress, by asking the patient to flex his hallux against the examiner resistance, with the ankle in slight dorsiflexion. The tendon normally relocated after the dynamic maneuver. Tendon dislocation was associated with a painful snap.

Flexor Hallucis Longus decompression under ultrasound guidance: A cadaver study

INTRODUCTION

The Flexor Hallucis Longus (FHL) is a muscle that can be subject to multiple impingements caused by exaggerated plantar flexion in athletes. The most common impingement is due to inflammation of the tendon at the retrotalar pulley. The constraints exerted on the FHL are responsible for a pathology called functional Hallux Limitus. Surgical treatment consists of tenolysis of the FHL arthroscopically or via open surgery, by opening the pulley. The objective of this study was to evaluate the risk of lesions of the neurovascular pedicle and the posterior tibial tendon after tenolysis of the Flexor Hallucis Longus under ultrasound guidance.

HYPOTHESIS

The hypothesis of this study is that tenolysis of the Flexor Hallucis Longus could proceed under ultrasound guidance without associated tendon lesions or neurovascular lesions.

MATERIAL AND METHODS

Thirteen cadaveric specimens were studied, resulting in an analysis of 26 feet. Following identification of the Flexor Hallucis Longus, tenolysis with a 19-gauge needle under ultrasound guidance was performed by an orthopedic specialist after hydrodissection to push back the posterior tibial pedicle. The dissection of the cadavers made it possible to verify the positioning of the posterior tibial pedicle, the FHL tendon and the opening of the retrotalar pulley.

RESULTS

Five cadaveric subjects, 10 cases, underwent a complete opening of the retrotalar pulley under ultrasound guidance. In 16 cases, the opening was partial, with a section of the pulley of 65.87±18%. The cases of partial openings showed no neurovascular or tendinous lesions. The 10 cases of complete opening resulted in 5 lesions of the tibial nerve, 4 vascular lesions: 1 venous and 3 arterial, and 6 lesions of the FHL tendon.

CONCLUSION

Tenolysis of the Flexor Hallucis Longus under ultrasound guidance at the level of its retrotalar pulley was systematically associated with neurovascular lesions in the event of complete release of the pulley by the method studied, unlike a partial release where no lesion was found.

LEVEL OF EVIDENCE

III; case-control study.

Hearing and Seeing Nerve/Tendon Snapping: A Systematic Review on Dynamic Ultrasound Examination

Nerve/tendon snapping can occur due to their sudden displacement during the movement of an adjacent joint, and the clinical condition can really be painful. It can actually be challenging to determine the specific anatomic structure causing the snapping in various body regions. In this sense, ultrasound examination, with all its advantages (especially providing dynamic imaging), appears to be quite promising. To date, there are no comprehensive reviews reporting on the use of dynamic ultrasound examination in the diagnosis of nerve/tendon snapping. Accordingly, this article aims to provide a substantial discussion as to how US examination would contribute to 'seeing' and 'hearing' these pathologies' different maneuvers/movements.

[Hallux saltans-rare diagnosis, often overlooked]

Hallux saltans is similar to digitus saltans and produces a spontaneous "snapping" of the big toe. This results in a constriction of the flexor hallucis longus tendon within the osteofibrous retromalleolar canal. The diagnosis was first described in 1940, and only a few case reports exist. We present the diagnosis and the treatment of a patient and give a review of the literature.

A problem-based approach in musculoskeletal ultrasonography: heel pain in adults

Musculoskeletal ultrasonography (US) has unique advantages, such as excellent spatial resolution for superficial structures, the capability for dynamic imaging, and the ability for direct correlation and provocation of symptoms. For these reasons, US is increasingly used to evaluate problems in small joints, such as the foot and ankle. However, it is almost impossible to evaluate every anatomic structure within a limited time. Therefore, US examinations can be faster and more efficient if radiologists know where to look and image patients with typical symptoms. In this review, common etiologies of heel pain are discussed in a problem-based manner. Knowing the common pain sources and being familiar with their US findings will help radiologists to perform accurate and effective US examinations.

Flexor Hallucis Longus Tendon Impingement Syndrome: All-inside Arthroscopic Treatment and Long-term Follow-up

This study aimed to evaluate the surgical technique and long-term clinical outcomes of all-inside arthroscopic treatment for flexor hallucis longus (FHL) tendon impingement syndrome. We retrospectively evaluated 34 FHL tendon impingement syndrome patients with complete follow-up data who were admitted from June 2015 to August 2018 and underwent the all-inside arthroscopy technique. The subjects consisted of 20 (58.82%) males and 14 (41.18%) females, with a mean age of 32.7 ± 10.2 (range 21-52) years. The cases consisted of 19 (55.88%) right and 15 (44.12%) left feet. The mean disease duration was 18.5 ± 9.1 (range 10-43) months. The visual analogue scale (VAS), American Orthopaedic Foot & Ankle Society (AOFAS), Karlsson Ankle Functional Score (KAFS), and 36-item Short Form Health Survey questionnaire (SF-36) scores for pain were 3.6 ± 1.2, 84.1 ± 9.6, 86.3 ± 10.7, and 94.7 ± 9.3, respectively. All patients were treated with all-inside posterior arthroscopy for the debridement of the FHL tendon sheath combined with partial muscle belly resection. Post-operative follow-up and observation of the patients' pain and ankle movement were evaluated using VAS, AOFAS, KAFS, and SF-36. All incisions were healed in the first stage, and no complications such as nerve, blood vessel, or tendon injuries occurred. The hospital stays were 3 to 5 days, with a mean of 3.7 ± 1.3 days. All patients were followed up for 12 to 36 months, with a mean follow-up time of 25.4 ± 8.5 months. By the last follow-up, the ankle joint and hallux movement were normal and returned to the pre-pain state for these patients. The VAS score decreased to 0.2 ± 0.1, while the AOFAS, KAFS, and SF-36 scores increased to 97.7 ± 8.5, 97.9 ± 8.2, and 118.2 ± 8.4, respectively. Advantages of all-inside posterior arthroscopic partial muscle belly resection for the treatment of FHL tendon impingement syndrome include small surgical trauma, fast functional recovery, and reliable outcomes. This procedure is therefore worthy of clinical attention and promotion.

Posterior Ankle Arthroscopy for Flexor Hallucis Longus Entrapment: A Case Report

Introduction:

Stenosing tenosynovitis is a chronic disorder frequently observed in finger triggering of a digit. Regarding the toes, although entrapment of the flexor hallucis longus (FHL) has already been reported in a few cases among sports players, the clinical condition is uncommon. Besides, the case without any specific causes is particularly rare.

Case Report:

We report the case of a 26-year-old male with FHL entrapment. Even though he was unaware of any cause, he felt tenderness on the posteromedial side of his left ankle, and his great toe was locked in the flex position. Magnetic resonance imaging indicated effusion in the tendon sheath of the FHL and the possibility of a partial tear of the FHL. We hypothesized that the scar tissue secondary to the partial tear of the FHL may have been irritated at the retrotalar pulley below the sustentaculum tali, where the FHL glides. Therefore, posterior ankle arthroscopy was performed for the treatment of the FHL entrapment.

Conclusion:

Orthopedic surgeons should list this pathology as a differential diagnosis of posterior ankle pain, even in non-athletes.

Ankle Injuries in Dancers

The term dance encompasses a broad range of different styles; much of the orthopaedic literature has focused on ballet dancers. Injury is common in dancers at all levels, and many serious dancers sustain multiple injuries as they progress through their career. Foot and ankle injuries are among the most common injuries experienced by dancers. These injuries include those that are specific to dancers because of the unique physical maneuvers required to effectively perform, but they can also include common injuries that may require relatively different treatment because of the physical demands of the dancer. Os trigonum syndrome and flexor hallucis longus tenosynovitis generally fall into the former category as they are injuries that are more prevalent in dancers due to the extreme plantarflexion involved in dancing, especially ballet, and the relative demand placed on the toe flexors, most notably the flexor hallucis longus. On the other hand, anterior ankle impingement occurs both in dancers and in the general public. In many cases, a team approach to treatment with knowledgeable physical therapists can obviate the need for surgical treatment. If surgical treatment proves necessary, good results can be achieved with sound surgical technique and a well thought-out rehabilitation program.