To Measure The Actual Defect Size Of Wound Through Skin Viscoelasticity And Discuss The Clinical Effect Of Skin Stretching For Closing Defect Wound

Objective: To explore the biomechanical properties of skin,a novel skin stretching device with rod was used to measure the actual defect size of wound through skin viscoelasticity,provide preconditions for the use of skin stretching technique in treating defect wound,and discuss the clinical effect of skin stretching for closing defect wound.Methods: From May 2015 to December 2016,the wounds of four extremities of15 cases(9 males and 6 females;mean age: 32.5 years old(17-53 years old))were closed by using the novel skin stretching device with rod.The widths of skin defect wounds were measured by using the device with rod.The pronated skin edges were trimmed 2 to 3mm,and skin edges on two sides were not free.The wound widths weremeasured in the following three conditions: wound defect width D1 was directly measured as the data of group A;the wound edges were pushed with both hands and folded together(Pinch experiment)to judge whether it is possible to close the wound with low tension,the result of the original Pinch experiment of wound was recorded,and wound defect width D2 was measured as the data of group B;hooked needle was installed at the wound site with high tension,and the needle inserting point on skin was5 to 10 mm away from the wound,reaching the subcutaneous tissue but not exceeding the fascia.According to the operation instructions,hooked needle slot and rod were installed,and two rows of hooked needles were folded to close the wound edges.The initial tension was recorded according to the tension scale.Wound defect width D3 was measured as the data of Group C when the scale was adjusted to low tension scale.The novel skin stretching device with rod was used to close wound: the number of the skin stretching devices was determined by the wound size.A set of skin stretching device was installed at the wound site with high tension with the same method mentioned above.Circulating load traction was carried out with four minutes of stretching and one minute of relaxation as a cycle.Arterial pulse was monitored during the whole process to closely observe any local color change of wound edges.Using skin viscoelasticity,local skin realized stress relaxation when skin was fully stretched until the tension scale of closing wound was a low tension scale.Time consumed for closing wound for each patient T was recorded.Skin stretching device with rod was removed.Wound tension was detected with the assistance of Pinch experiment.The final results of Pinch experiment were recorded.Wound with low tension was closed with suture.The follow-up was one year.The complete wound healing times and incision complications of these patients were analyzed to evaluate the clinical outcome.Results:1.There were statistically significant differences between group A(wound defect width measured directly)and group B(wound defect width measured by pushing withboth hands and folding together wound edges(Pinch experiment))and between group A(wound defect width measured directly)and group C(wound defect width measured on the low tension scale of skin stretching device),but there was no statistically significant difference between group B and group C.2.The initial closure tension of all wounds: 8 cases had high scale tension;7 cases had medium scale tension;the final closure tension was low scale tension;the final Pinch experiment was negative;the mean time of using the stretching device was 48minutes(15-82 minutes);7 patients were followed up at 3 to 8 months(4.8 months on average).All wounds were healed at stage I and the mean healing time was 14 days.No skin edge necrosis,incision infection and scar hyperplasia were noted after operation.Conclusions:1.The measurement of wound defect width using skin stretching device on low tension scale is more objective and accurate than the other two methods;2.The novel skin stretching device with rod has objective tension scale and is minimally invasive.It can fully take advantage of skin viscoelasticity to close wound with low tension,avoid skin-grafting or flap surgery and provide a very safe and effective treatment method for larger wounds on upper limbs.