Recovery of sensation in free flaps

Abstract

A clinical study of touch, pain, warm and cold stimuli and two-point discrimination was performed in 27 free flaps four months to four years after the microsurgical procedure. There were 5 free skin flaps (2 with nerve suture), 15 musculocutaneous, 4 muscle-covered with split skin grafts and 3 osteomusculocutaneous flaps transplanted to various sites on the body. The results show full or nearly full recovery of touch and pain sensation in all free skin flaps. The musculocutaneous and osteomusculocutaneous free flaps developed good sensation if firmly grown onto the healthy recipient skin with normal sensation. Muscle flaps covered with split skin grafts and all flaps surrounded by scar tissue had a clinical absence of sensation. This study and our earlier findings of the regeneration of nerves in free skin grafts, in skin flaps and in experimental free flaps, lead us to suggest that the healthy denervated skin of the free flap provides a strong neurotrophic stimulus to the cut cutaneous nerves in the edges of the recipient skin. Cutaneous nerves freely regenerate in the loose subcutaneous tissue of the flap. We therefore conclude that all free flaps with skin islands have a potential for developing sufficient protective touch and pain sensation and even some superficial sensitivity.

Sensory recovery of noninnervated free flap in oral and oropharyngeal reconstruction

“…A number of authors have reported successful sensory recovery using innervated free flaps in oral and oropharyngral reconstruction 2,7,10,14,20 . In contrast, spontaneous recovery of sensation in noninnervated flaps has also been reported 3,4,13,23 .…”

Influence of human skin injury on regeneration of sensory neurons

“…Although the scar tissue may hamper regenerating nerves, hypertrophic scars may be penetrated by regenerating nociceptive nerves, as there is an increase in the levels of substance P and CGRP in the basal epidermis of these tissues (Parkhouse et al 1992). On the other hand, a lack of the full recovery of sensation in surgical flaps (Lahteenmaki et al 1989;Rath and Green 1991) or skin grafts may be explained by poor trophic influences of factors from the target tissue. Amongst the many treatment modalities of painful neuromas, relocation of the amputated nerve stumps into muscle or bone or "wrapping" of the stump by fat or fascia are recognised as being successful (Jones 1996;Sood and Elliot 1998).…”

Reinnervation of Split Skin Grafts in Humans: Comparison of Two Different Methods of Operation

“…Clinical and experimental studies have shown that the pattern of reinnervation is similar to that of the recipient site (10,14,21). Nerves may regenerate incompletely (9,12,15,27) or sensory and autonomous functions may be totally absent (8,13,30). Apart from differences between various types of grafts, the degree of reinnervation also differs among grafts of the same kind (14,(21)(22)(23) because of the many factors that influence nerve regeneration including the thickness of the skin graft (17,21), the bed of the wound and the surrounding tissue (14,21), and the postoperative course (21).…”