The MRI appearance of myloglossus.

PURPOSE: This case report describes the MRI appearance and significance of the myloglossus muscle, a variant extrinsic tongue muscle. METHODS: The myloglossus muscle was incidentally discovered on imaging performed for head and neck cancer evaluation. RESULTS: The myloglossus is best visualized on non-fat saturated T2 MRI and has signal characteristics that match those of muscle. It originates at the angle of the mandible and inserts into the tongue between the styloglossus and hyoglossus. CONCLUSION: Accurate identification and delineation of the extrinsic muscles of the tongue, including the myloglossus, is essential for proper staging and treatment of head and neck cancers. This case report attempts to fill a void in depicting the MRI appearance of myloglossus muscle.

Unusual bilateral variation of the flexor digitorum accessorius longus muscle and its relation on tarsal tunnel syndrome.

PURPOSE: During standard anatomical dissection for a medical anatomy course, we encountered an unusual bilateral variant of a unipennate flexor digitorum accessorius longus (FDAL) muscle, a supernumery muscle of the deep posterior leg and medial ankle. METHODS: We documented the muscles course and measured the diameter and length of the FDAL muscle belly, as well as the full length of its tendinous attachments. RESULTS: On both right and left legs, the FDAL originated from the proximal posterior fibula and distal one-third of the flexor hallucis longus muscle. The tendon had a distal attachment on the flexor digitorum longus (FDL) tendon and traveled with the FDL tendon as it inserted on the third distal phalanx. The left FDAL full length was 42.54 cm; the length of the muscle belly was 16.26 cm; and the circumference of the muscle belly was 4.44 cm. The right FDAL full length was 44.20 cm; the length of muscle belly was 12.06; and the circumference (belly) was 4.44 cm. Surrounding musculature and neurovasculature follow standard anatomical courses. CONCLUSION: This anatomical documentation provides opportunities for clinicians to consider mechanical influences of the FDAL on plantar foot function and further consider the accessory ankle muscles that have the potential to cause compressive neuropathies such as tarsal tunnel syndrome.

Muscular variations during axillary dissection: a clinical study in fifty patients.

AIM: The present study was conducted to detect the musculature variations during axillary dissection for breast cancer surgery. METHODS: The anatomy of axilla regarding muscular variations was studied in 50 patients who had an axillary dissection for the staging and treatment of invasive primary breast cancer over one year. RESULTS: In a period of one year, two patients (4%) with axillary arch and one patient (2%) with absent pectoralis major and minor muscles among fifty patients undergoing axillary surgery for breast cancer were identified. CONCLUSIONS: Axillary arch when present should always be identified and formally divided to allow adequate exposure of axillary contents, in order to achieve a complete lymphatic dissection. Complete absence of pectoralis major and minor muscles precludes the insertion of breast implants and worsens the prognosis of breast cancer.

Estudio anatómico del fascículo accesorio del músculo flexor largo del pulgar y su relación con el nervio interóseo anterior en individuos brasileños / Anatomical study of the accessory head of the flexor pollicis longus muscle and its relationship to the anterior interosseous nerve in Brazilian individuals

Entre los síndromes de compresión nerviosa en el antebrazo, debido a la presencia de arcos tendinosos de músculos relacionados al trayecto de los nervios que transcurren entre sus capas musculares, se encuentra el del nervio interóseo anterior (NIA). La presencia de variaciones musculares puede generar arcos que ocasionan compresión nerviosa. El objetivo fue establecer la incidencia y morfología del músculo accesorio del flexor largo del pulgar (AFLP) y la relación de éste con el NIA o sus ramos motores. Se utilizaron 30 antebrazos, de cadáveres formolizados de individuos adultos brasileños. El punto de referencia seleccionado para las mediciones fue el epicóndilo medial del humero (EMH). Se observó que tres miembros superiores presentaron el AFLP (10%), en todos ellos se originó en el EMH para terminar insertándose en el tendón del músculo flexor largo del pulgar (FLP). El vientre muscular presentó aspecto fusiforme, el cual tenía un tendón que formó un arco con el FLP. En uno de los casos, este arco se relacionó con el paso del NIA; en los otros dos, lo hizo con los ramos motores que se originan del NIA. Al diagnosticar los síndromes generados por compresión nerviosa se debe considerar la presencia del AFLP, el cual, potencialmente se puede relacionar con el trayecto del NIA o de sus ramos.

Between the syndromes of nerve compression in the forearm, due to the presence of the tendinous arches related to the nerves that pass between its muscle layers, is the anterior interosseous nerve (AIN). The presence of muscular variations can generate arches that cause nerve compression. The aim of our study was to establish the incidence and morphology of the accessory head of flexor pollicis longus muscle (AFPLm) and its relationship with AIN or its branches. Thirty forearms of formalized corpses of adult Brazilians were used. The selected landmark for measurements was the medial epicondyle of the humerus (MEH). It was noted that three upper limbs presented the AFPLm (10%), originated from the MEH to end inserted into the tendon of the flexor pollicis longus muscle. The AFPLm showed fusiform appearance, which had a tendon that formed an arch with the flexor pollicis longus muscle. In one case, this arch was associated with the passage of AIN. In the other two, this arch was related to motor branches originating from the AIN. The diagnosis of nerve compression syndromes should consider the presence of AFLPm, which potentially can be related to the course of the AIN or its branches.

Fleshy palmaris longus muscle - a cadaveric finding and its clinical significance: a case report.

INTRODUCTION: Palmaris longus variations may include complete agenesis, variation in the location and form of the fleshy portion, aberrancy in attachment, duplication or triplication, accessory tendinous slips, replacing elements of similar form or position. Description of case: An anomalous palmaris longus muscle was found in the right upper extremity of a 63 year-old male cadaver. The muscle was totally fleshy without a long insertion tendon. Its origin was normal, the belly was rather broad and long, fusiform at the upper half and unipennate at the lower half of the forearm, and it was toggled into a short and thick tendon. At its insertion the tendon was split forming a second thinner tendon. The thick tendon was inserted into the flexor retinaculum and the thinner one into the palmar aponeurosis. The muscle compressed the median nerve although no related symptoms were reported on the cadaver's medical history. DISCUSSION: This variation is of clinical importance because it may cause carpal tunnel syndrome or difficulties in image interpretation by radiologists. In addition the palmaris longus muscle is an anatomical landmark for operations at the forearm and wrist and its tendon can be used as a graft.