Five Centimeters Morton's Neuroma in a 46-Year-Old Woman Affected by Macrodactily.

The present article described the case of a voluminous Morton's neuroma of the third intermetatarsal space in a patient affected by macrodactily. The case was unique because of its dimensions, the uncommon surgical approach which was needed for removal, the association with macrodactily of the fourth toe with Raynaud's phenomenon, and the postoperative defect in the intrinsic muscles. The patient was operated in February 2016 by transverse plantar approach. Twelve months after surgery, the patient complained for hypoesthesia on third and fourth toes with inability to actively spread the toes and enlargement in the second interdigital space. The dimensions of the lesions may be explained with the presence of macrodactily in the fourth toe with occasional Raynaud's phenomenon, which may have caused an abnormal arrangement of the nerve branches for the fourth interspace with related microtrauma. A plantar approach was highly recommended as the size of the lesion forced it to the plantar surface of the foot. The inability to actively spread the toes and the enlargement of the second interdigital space are likely to be related to a deficiency of the interosseous muscles, innervated by the deep branch of the lateral plantar nerve, which had probably been sacrificed because of the size of the lesion and the subversion of the surrounding anatomical relationships.