A CASE OF DISTAL ULNAR NERVE VARIATION – PRESENCE OF SENSORY LOOP AROUND THE HOOK OF THE HAMATE BONE. Un caso de variación distal del nervio ulnar – Presencia de un bucle alrededor del gancho del hueso ganchoso


  • Alexander K Angelov Department of Anatomy, Histology and Embryology, Medical University of Sofia, Sofia
  • Lazar Jelev Department of Anatomy, Histology and Embryology, Medical University of Sofia, Sofia



Palabras clave:

ulnar nerve variation, neural loop, hamate bone, flexor retinaculum, clinical implications, variación del nervio ulnar, lazo neural, hueso ganchoso, retináculo flexor, implicaciones clínicas


Las variaciones del nervio cubital ulnar en la muñeca son extrañas, pero todavía tienen importancia clínica. Durante una disección de rutina de la mano derecha de un hombre europeo de 67 años, se encontró en la muñeca  un nervio ulnar aberrante. Su rama superficial se bifurcó y formó un lazo completo alrededor del gancho del hueso ganchoso. Los nervios sensoriales de los dedos surgieron de las diferentes partes de este lazo. La presencia de dicha variación predispone al nervio a una neuropatía por compresión incluyendo una lesión accidental ocasionada durante las intervenciones quirúrgicas.


Ulnar nerve variations in the wrist are rare but still have clinical importance. In the course of a routine dissection of the right hand of a 67-y-old Caucasian male cadaver an aberrant ulnar nerve at the wrist was found. Its superficial branch bifurcated and formed a complete loop around the hook of the hamate bone. The sensory digital nerves arose from the different parts of this loop. The presence of such a variant neural loop predisposes the nerve to compression neuropathy and accidental injury during surgical interventions.


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