An Anatomic Analysis On Design The Segmental Latissimus Dorsi Flap And Clinical Study On Function At The Donor Site After Flap Tranfer

Chapter 1 An Study on the Segmental Latissimus Dorsi Flap Design Analysis of the AnatomyObjective To design the segmental latissimus dorsi flap and provide alternatives to reserve the function of the shoulder and upper arm,dissect and analysize the position,distribution,vascular pedicle length and diameter of thoracodorsal artery and its branches supplying latissimus dorsi and the relationship between thoracodorsal nerve and thoracodorsal artery and the scope of the latissimus dorsi supported by every branches.Study and improve mechanism of blood supply and innervation of every segment of the latissimus dorsi,explore the feasibility and necessity of the function of the remaining latissimus dorsi after the segmental latissimus dorsi flap transfer.Methods Ten fresh cadaver specimen were perfused through artery by gelatin-lead oxide,and the left and right side of the latissimus dorsi muscle were microdissected,and thoracodorsal artery and its branches and thoracodorsal nerve and its branches were isolated.Record the vascular anatomy of thoracodorsal artery branchs including vascular morphology,run,distribution,vascular pedicle length of every branch,diameter of every branch,and the relationship between thoracodorsal nerve and artery.On the basis of the dissecting relationship between the thoracodorsal artery and nerve,choose suitable segmental latissimus dorsi muscle for transferring,leaving the remaining latissimus dorsi function intact.Results Twenty cases of the latissimus dorsi autopsy specimens were observed anatomically the constant thoracodorsal artery.There were 20 cases to be found the lateral branch from thoracodorsal artery,while 18 cases to be found the medial branch from thoracodorsal artery.The thoracodorsal artery bifurcation was away from the average distance of 3.8 cm under the shoulder angle and apart from the latissimus dorsi medial average distance of 2.3cm.The thoracodorsal nerve run with the thoracodorsal artery,and the thoracodorsal nerve bifurcation was about 1.2cm higher than the thoracodorsal artery bifurcation.The medial branch run parallel to the superior border of the muscle on average 3.4 cm below it,with a lateral branch running parallel to the lateral border of the LD muscle 2.2 cm medial to it.The mean length of the vascular pedicle from its origin at the subscapular artery to the thoracodorsal artery lateral branch entering the LD muscle was 10.41 cm(9.07–12.45,n=20),while that to the medial branch of the thoracodorsal artery entering the LD muscle was 9.07 cm(7.98–10.79,n=18).There was a statistically significant difference(p < 0.001)in the pedicle length based on the lateral branch compared with that based on the medial branch.The mean diameter of the lateral branch at the departure of the thoracodorsal artery was statistically significantly greater than that of the medial branch(p<0.001).Conclusions(1)The lateral branch of the thoracodorsal artery running constantly in the latissimus dorsi deep surface can be used as a vascular pedicle.The diameter,vascular pedicle length and distribution location of the lateral branch of thoracodorsal artery are better than those of the medial branch,so it has more advantages for harvesting the segmental latissimus dorsi as a free flap with the lateral branch as a vascular pedicle.(2)Because the thoracodorsal artery runs with the thoracodorsal nerve with at least 2cm between them,and the thoracodorsal nerve bifurcation is higher than the thoracodorsal artery bifurcation,so during dissecting the vascular pedicle,the thoracodorsal nerve dominating the remaining latissimus dorsi can be protected.Chapter 2The Clinical Study on Function at the Donor Site after Harvesting Segmental Latissimus Dorsi FlapObjective The purpose of the present study was to evaluate arm and shoulder function prospectively after transfer of the lateral segment of the latissimus dorsi muscle based on mediun and small wound with the lateral branch of the thoracodorsal artery as the vascular pedicle leaving the remaining latissimus dorsi nerve intact.Methods Twenty patients were recruited from our department from September 2010 to February 2014,whose wound locating in lower extremity were repaired by the lateral segmental latssimus dorsi free flap with the lateral branch of the thoracodorsal artery as the vascular pedicle leaving the remaining latissimus dorsi nerve intact,and functional disability was determined by the Disabilities of Arm,Shoulder,and Hand(DASH),and muscle strength by needle electromyography(EMG)before surgery and at five different time points postoperatively.Results These 20 flaps survived postoperatively except for one distal necrosis,and wound healing by dressing.The phenomenon of flap blood supply poor including severe swelling,blood stasis purple and vascular crisis didn’t appear after 2 weeks postoperatively,every wound healing was good.At half a month and 1 month postoperatively,the scores were clinically and statistically significantly increased from the preoperative mean(mean DASH: half a month review 28.50,p < 0.001;1 month 19.61,p < 0.001).However,the score 3months after surgery was statistically significantly higher than the preoperative score(mean DASH;3 months review 12.61,p < 0.001).DASH scores tended to plateau at 6and 12 months postoperatively,which were still statistically significant(both p < 0.001).At 3months postoperatively,the p-valuewas 0.023,which was found to be statistically significant.The mean amplitude 6 and 12 months after surgery was found to be almost the same as before surgery.Conclusions Lateral segmental LD muscle transfer,leaving the residual segment motor function intact,can be recommended as an alternative for moderate and small-size bone exposure wounds,especially in the lower extremities,that minimizes loss of donorsite function.