Clinic And Morphologic Observation On The Sensory Recovery Of Random Pattern Skin Flap Of Abdominal Region In Repairing Cutaneous Deficiency Of Finger Tip

Objective: Skin is covering the whole body, with protection, aesthetics, regulating body temperature, shock absorption, dispersion pressure and other functions. Skin was often injured by external factor, then the formation of skin and soft tissue defect occurred. Today, with the rapid development of industry and agriculture, the hand is more vulnerable injured, the skin defect of finger tip accounts for a large proportion of hand injuries.Abdominal skin flap can repair cutaneous deficiency of finger tip,which is a more traditional, mature surgical approach, and postoperatively most of the flaps were satisfied.According to the basic of anatomic, the blood supply of random pattern skin flap, with only the capillary network in dermis and the vascular network under the dermis ,is from the muscle cutaneous artery branch. Early research mostly concentrated in the blood supply of flap, this study was to evaluate the sensory function of random pattern skin flap of abdominal region in repairing cutaneous deficiency of finger tip, returned to guide patients should pay attention to the problems of life and avoid damage.Methods: From September 2010 to February 2011, 23 pationts with cutaneous deficiency of finger tip (30 digits) were treated with random pattern skin flap of abdominal region .Their ages ranged from 18 to 50 years,with a mean age of 31 years.After debridement the defect area was 0.7cm×1.2cm 2.5cm×3cm. 3 weeks later at the second stage,flap pedicle was divided. Postoperatively the patients were followed up for 1 week to 6 months,.The cont of detection includes: tactile sense, pain sense, temperature sensation and two point discrimination .Tactile sense was tested by a cotton bud; pain sense was tested by a 2ml syringe needle; temperature sensation was tested by two test tubes with 0℃ 10℃cold water and 50℃ 60℃hot water; two point discrimination was tested by of blunt compasses . On the basic of British Medical Research Institute sensory function was divided into six grade, S₄: normal sensation; S₃⁺: partial recovery of two points discrimination; S₃: superficial tactile sense and pain sense recovery, hypersensitivity disappeared; S₂: partial recovery of tactile sense and pain sense; S₁: deep pain sense recovery; S₀: no sensory recovery. 2-finger flaps were made thinner by surgery after 3 months, and 2-finger flaps were made thinner by surgery after 6 months .During the operation we cut some tissue of flaps to biopsy, using HE staining and special staining, to observe the regeneration of sensory nerve in flap with optical microscope at different periods.Results: All the flaps survived. Postoperatively follow-up ranged from 1 week to 6 months.Pationts basically satisfied with the appearance of the fingers and the flaps, only 4 patients have the second operation to make the flap thinner.All flaps had satisfactory flexibility and texture. Sensory recovery were satisfacted.We presumed the recovery order is touch and pain sensation, cold sensation, heat sensation, two points discrimination. Sensory recovery was from proximal end to distal end , and from circumferentia to the center. 6 months later the sensory recovery of the flaps: the sensory function of all flaps are all up to S₃⁺. No donor site complications occured. Light microscope observation: 3 months later we could see few free nerve endings in cuticular plate, and some nerve fibers in reticular layer,but the density was lower; 6 months later , many nerve endings were in cuticular plate,and more nerve fibers were in dermis plate.We could see Meissner corpuscles in papillar layer, Merkel cells in basal layer of cuticular,and complete Pacinian corpuscles in deep dermis plate.Conclusions: Random pattern skin flap of abdominal region is a simple and safe method to repair skin defects of finger tip, without sacrificing the appearance and function of the other fingers. The treatment outcomes were satisfactory.The sensory nerves of flap can be regenerated, and the direction of regeneration is generally from proximal end to distal end, and from circumferentia to the center.