Variant distribution of the calf cutaneous nerves - case report and clinical impact

We report a cadaveric case of unusual innervation pattern of the right calf and ankle. During dissection of an 82 years-old, formalin-fixed, male cadaver, the posterior femoral cutaneous nerve was found providing sensory supply to the lateral knee region, while it terminated at the level of the ankle. Moreover, the medial sural cutaneous nerve did not anastomose with a peroneal communicating branch and it continued as the lateral dorsal cutaneous nerve of the foot. In cases that the peroneal communicating branch is absent, the medial sural cutaneous nerve is called sural nerve. Additionally, the lateral sural cutaneous nerve travelled over the calf crossing the sural nerve at its middle and thus, providing sensory supply to the upper lateral calf and the lower medial aspect of the calf and ankle. This peculiar sensory supply may cause diagnostic hazard in cases of nerve injury with neurological symptomatology, whereas due to the presented variability, nerves are prone to iatrogenic injury during procedures in the area.