Accessory head of the flexor pollicis longus muscle: anatomical study and clinical significance.

BACKGROUND: The accessory head of the flexor pollicis longus (AHFPL) has an oblique trajectory from medial to lateral aspect of the forearm below the flexor digitorum superficialis muscle and then joins the flexor pollicis longus muscle. When the anterior interosseous nerve (AIN) courses underneath the muscle belly of the AHFPL an entrapment neuropathy may occur, known as anterior interosseous nerve syndrome (AINS). MATERIALS AND METHODS: This descriptive cross-sectional study evaluated 106 fresh upper extremities. When the AHFPL was present, its fascicle was traced up to evaluate the origin site. The morphometric variables were measured using a digital micrometre (Mitutoyo, Japan). The relationship between the AHFLP and the AIN was evaluated. RESULTS: The AHFPL was found in 34 (32.1%) of the 106 forearms. The AHFPL arose from the flexor digitorum superficialis muscle in 16 (47.1%) forearms, the medial epicondyle of the humerus in 10 (29.4%) forearms and the coronoid process of ulna in 8 (23.5%) forearms. The average total length of the AHFPL was 94.11 ± ± 10.33 mm. The AIN was located lateral to the AHFPL in 3 (8.8%) forearms, posterolateral in 7 (20.6%) forearms and posterior in 24 (70.6%) forearms. CONCLUSIONS: This study performed in a South American population sample revealed a prevalence of the AHFPL in a lower range compared to previous studies in North Americans and Asians. The AIN coursed more frequently underneath the muscle belly of AHFPL. This finding has clinical significance in the onset of the AINS and the subsequent surgical procedure for the AIN decompression.

Variaciones vasculares en cavidad abdominal y de vías urinarias: presentación de caso / Vascular variations in urinary tract and abdominal cavity: case report

Se presenta un raro caso de múltiples variaciones en la cavidad abdominal de un espécimen cadavérico de 50 años de género masculino, del laboratorio de anatomía de la Universidad Industrial de Santander (Bucaramanga-Colombia). Se observó variaciones arteriales (arteria renal adicional derecha y origen de la rama hepática derecha desde la arteria mesentérica superior), venosa (vena renal derecha adicional) y de vía urinaria (doble uréter en el lado derecho). Estas diversas variantes anatómicas además de suscitar interés académico, deben ser consideradas y descritas correctamente por los clínicos durante la realización de procedimientos quirúrgicos, radiológicos y de imágenes diagnósticas en la cavidad abdominal.

Here we present a rare case of multiple abdominal cavity variations in a 50-year-old male cadaveric specimen of the anatomy laboratory of the Universidad Industrial de Santander (Bucaramanga, Colombia). The anatomical dissection revealed arterial variations (right additional renal artery and origin of the right hepatic branch from the superior mesenteric artery), venous (right additional renal vein) and urinary tract (duplicated ureter on the right side). These multiple anatomic variations in addition to raising academic interest, should be considered and described correctly by clinicians while performing surgical, radiological and imaging procedures in the abdominal cavity.