Clinical Application Of Sural Neurofasciocutaneous Flap In Children Patients And Analysis Of The Influencing Factors Contributing To The Survival Rate Of The Flap

Objective: To summarise clinical application experience of sural neurofasciocutaneous flap in children patients, discuss the clinical characteristics of sural neurofasciocutaneous flap in children patients, analyze the influencing factors contributing to the survival of the flap.Method: Using 33 sural neurofasciocutaneous flaps to reconstruct soft tissue defect of lower leg, foot and ankle in children patients from April of 2001 to April of 2008, The age of the patients ranged from 3 to 13 years old, the average age is 7 years old. Thirty-two flaps soft tissue defects were caused by trauma, which all complicate with the exposed bone, joint, muscle tendon tendon. The other one defect was caused by disposing the unstable scar. 25 flaps position located in heel defects and Achilles tendon or ankle, 6 falps in region dorsd is pedis. 2 flaps in inferior segment of leg (2). 32 flap's extremity distal surpassed the one third juncture between middle segment and upper segment of the leg. One flap's extremity distal below the one third juncture between middle segment and upper segment of the leg. The size of the flaps ranged from 6cm×5cm to 16cm×10cm. The length-width ratio of the flap ranged from 3/1 to 5.67/1. The pivot points lied ronged from 4.5cm to 12 cm above the fip lateral malleolus. All 33 flaps are almost distally based sural neurofasciocutaneous flaps, One of them is distally-based cross-leg sural neurofasciocutaneous flap. The lower leg length (the distance between the tip of the lateral malleolar and popliteal crease) is divided to 9 equall parts, and location of the flap is defined as leg zonation which the flap extremity distal to the pedicle lies in. The definition of the flap length-width ratio is that the length of the flap puls the length of the pedicle conpare to the width of pedicle. The statistics was used to analyze the influencing factors contributing to the survival rate of all flaps retrospectively. There are several influencing factors analyzed, include sex, age, defect, pivot point location, flap length-width ratio, flap location, flap length plus pedicle length, flap width and pedicle length-width ratio. The multiple factors (sex, age, defect location, pivot point location, flap length-width ratio, flap location) is analyzed with statistics method. The statistics was used to compare the survival rate and factors impacted on the survival (the length-width ratio of flap, flap location) of 33 of children flap's usedsural neurofasciocutaneous flap and 79 cases of adult sural neurofasciocutaneous flap of same period. Statistics analytical method: t-test and chi square test are used for uni-factor analysis; Logistic regression analysis is adopted for multi- factor analysis.Result: Among these 33 flaps, 30 flaps survived uneventfully; The totally survival rate is 90.9%; distal partial necrosis took place in 3 flaps, which wound surfaces healed by changing dressings, secondary suture or skin grafting respectively; All of the wound is eliminated by the flap. the survival rate of the length-width ratio less than 5 group(92.6%,25/27) is higher than that of the length-width ratio more than and equal to 5 group(83.3%,5/6) (P=1.000); One flap survived uneventfully, which extremity distal lower the juncture between middle segment and upper segment of the leg. 32 flap's extremity distal surpassed the one-third juncture upper one-third segment of the leg and the survival rate is 90.6%. The survival rate of the flap location less than and equal to 7/9 group(100 %,14/14)is higher than that of the flap location more than 7/9 group(78.9 %,16/19)(P=0.244); The survival rate of the flap location less than and equal 8/9 group(91.7%,22/24)is higher than that of the flap location more than 8/9 group(77.8%,8/9)(P=1.000). Logistic regression analysis showed that pivot point affect the survival of a flap, The survival rate of the pivot points lower than and equal 6cm above the tip of the lateral malleolus group(96%,24/25) is higher than the pivot point higher than 6cm above the tip of lateral malleolus group(75%,6/8). The survival rate of children sural neurofasciocutaneous flap group and adult sural neurofasciocutaneous flap group were respectively 90.9% (30/33), 88.6% (70/79); The comparison of the factors impacting the flap's survival (the ratio flap, flap position) between children and adults has no significant difference.Conclusion: (1) The survival rate of the sural neurofasciocutaneous flap in children is also high when the flap location surpassed the one-third juncture between middle segment and upper segment of the leg; the flap survived reliable when flap position in the lower 7/9 of the leg (including reach 7/9); (2) With the length-width ratio increasing, the survival rate of children sural neurofasciocutaneous flap decreased progressively; (3) The impact of the length-width ratio and location of flap on the flap's survival has no significant difference between children and adults.