An Erratic Origin of Quadratus Plantae: An Embryological Error

Background: Quadratus plantae (Flexor digitorum accessorius) is one of the plantar muscles of foot . It is present in the second layer of sole. It takes origin from calcaneus and gets inserted into the tendon of flexor digitorum longus. The main function of it is to flex the lateral four toes in any position of the ankle joint by pulling on tendons of the flexor digitorum longus. Its variations like high origin have been implicated in the causation of tarsal tunnel syndrome. Methodology and Results: In routine dissection done on 22 cadavers, we observed a bilateral variant muscle flexor digitorum accessorius longus on both right and left sides in a male cadaver. The modality of choice in diagnosing the accessory muscle is magnetic resonance imaging. Conclusion: The knowledge of this variation would be essential to anatomists, radiologists and also to the foot surgeons while performing posterior ankle endoscopy. KEY WORDS: Flexor digitorum Accessorius longus, Tarsal tunnel syndrome, Posterior ankle endoscopy.

Tarsal Tunnel Syndrome Secondary to Accessory Musculature: A Case Report

Tarsal tunnel syndrome (TTS) is a relatively uncommon compression neuropathy caused by impingement of the tibial nerve or one of the terminal branches. The presence of accessory musculature at the posteromedial aspect of the ankle has been identified as a rare cause of this condition. Despite the rarity of this condition, it must be considered in patients with refractory symptoms consistent with tibial nerve dysfunction. The accurate diagnosis of this condition relies heavily on a detailed history and physical examination, adequate imaging read by both surgeon and trained musculoskeletal radiologist, as well as a high level of suspicion for such pathology. In this case report, we describe a 46-year-old male with history, examination, and imaging all consistent with TTS secondary to accessory musculature. Following excision of an accessory soleus and flexor digitorum accessorius longus, as well as simultaneous tarsal tunnel release, the patient experienced full resolution of his symptoms. This highlights the importance of considering accessory musculature as a potential cause of TTS in patients presenting with tibial compression neuropathy. Levels of Evidence: Level V: Case Report

Supernumerary muscle of tarsal tunnel: a case report

Supernumerary muscles are an infrequent fmding during dissections around the ankle. This report focusses on the finding of one such muscle which was found in the tarsal tunnel of the left lower limb unilaterally during routine dissection of a 70 year old male cadaver in Bankura Sammilani Medical College, West Bengal.This supernumerary muscle had a single head of origin from the flexor hallucis longus and posterior intermuscular septum and was traced to its insertion into the flexor digitorum accessorius in the sole and hence was named flexor digitorum accessorius longus, and its relations with the neurovascular bundle were noted. Flexor digitorum accessorius longus may be a cause of tarsal tunnel syndrome so it should be kept in mind during its management. It may also produce symptoms mimicking soft tissue tumors. Thus knowledge of this muscle will be of utmost importance to anatomists, clinicians, radiologists and athletes.

Anatomical Characteristics of the Flexor Digitorum Accessorius Longus Muscle and Their Relevance to Tarsal Tunnel Syndrome

Background Clinical and cadaver studies have reported that supernumerary muscles could be the etiology of a variety of pathologic disorders, such as posterior impingement syndrome, tarsal tunnel syndrome (TTS), and flexor hallucis longus tenosynovitis. We describe a unique variant of the flexor digitorum accessorius longus (FDAL) muscle as an apparent cause of TTS, functioning as an independent flexor of the second toe, which has not been described in the literature. In addition to this case report, a systematic review was performed of TTS caused by the FDAL muscle. Methods A targeted search of PubMed, the Cochrane Library, the Cumulative Index to Nursing and Allied Health Literature, and Web of Science identified full-text papers that fulfilled the inclusion and exclusion criteria. Results Twenty-nine papers were identified for inclusion in the systematic review: 12 clinical papers of TTS caused by the FDAL muscle and 17 cadaver-based papers. Conclusions Clinicians often do not include the FDAL muscle in the differential diagnosis of TTS. This literature review suggests that the FDAL is an important muscle in terms of its functional and clinical significance. Knowledge of this muscle, its anatomical location and variations, and its magnetic resonance imaging characteristics may help clinicians make an accurate differential diagnosis.