Anatomic And Clinical Study On Treatment Of The Burst Fractrue Of Upper Thoracic Vertebras With Paralysis Through The "U" Fenestration Approach In The Sternal Manubrium

Objective:1 To observe the anatomy of the sternal manubrium and upper thoracic vertebras. Studyed the feasibility of the "U" fenestration in the sternal manubrium to approach the upper thoracic vertebra.Build an anatomic foundation for clinic.2 Anatomised important vessels and nerves,researched the anatomic relationships between them and upper thoracic vertebras.To contrast the left approach with the right one about surgical risk maked reference for clinic.3 To observe clinic curative effect in the treatment of burst fracture of upper thoracic vertebra with paralysis through the "U" fenestration approach in the sternal manubrium.Explored the advantage and caution of the approach.Method:1 We measure the mean width of upper thoracic vertebras(a) and the narrowest width of the sternal manubrium(b) of 35 corpse samples,Calculated the value of a/b(%).Defined the vertebra which level is just higher than the sternal cornu as the observed one on 50 MRI samples.To measure the length between level projection of the lower border of observed vertebra in the sternal manubrium and midpoint of the jugular notch(c) and the legth of the sternal manubrium(d).Calculated the value of c/d(%).2 Through the "U" fenestration in the sternal manubrium,the left anterior surgical approach to the upper thoracic vertebrae were done in 35 corpse samples.Observed the surgical field through the organic clearance which is between the left common carotid artery and the trachea and esophagus.To measure the origin and course of the recurrent laryngeal nerve,thoracic duct,and relationships between them with upper thoracic vertebraes.3 We treated 12 patients with the burst fracture of upper thoracic vertebra who had 6 with complete and others with incomplete paralysis.All cases treated through the "U" fenestration approach for anterior decompression and stabilization.Result: 1 The mean valuses of a/b is(78±7.9)%.a/b＜1,so the "U" fenestration in the sternal manubrium could approach upper thoracic vertebra in Coronal plane,we only need to excise (78±7.9)%of the narrowest width of the sternal manubrium.There are 46 samples(92%) which lower border of T₄ are higher than the level of the sternal cornu on 50 MIR samples.So T₄ is the observed one.The mean values of c/d is(72±14.7)%.c/d＜1,so the "U" fenestration in the sternal manubrium could approach T₄ in Sagittal plane.To approach T₄ vertebra,we only need to excise(72±14.7)%of the length of the sternal manubrium.2 There are the 91.4%of samples which could be approached to T₄ vertebra by the space(borders:right—the left common carotid artery;left—the trachea and esophagus;inferior-the left innominate vein).The right recurrent laryngeal nerve which derives from vagus nerve at the level of T_1～2 reaches the tracheoesophageal groove at the level of T₁.It is across between common carotid artery and tracheoesphageal theca at the level of T_1～2 and liable to stretching injury;The thoracic duct ascend closed with the left side of tracheoesphageal theca.It aparts from the tracheoesphageal theca at the level of T₂ and go with the left subclavian artery immediately.It could be protected because of it's anatomy characteristic.So, it should take the left anterior approach to upper thoracic vertebras when do surgery.3 Cases were followed up for 1～7years,all got the fusion of bone graft.Loosening and breakage of the internal fixators were not found in all cases.There were no occurrence of incision infection,asphyxia,pneumothorax,chyle leakage,pulmonary infection etc.9 got motor and sensor recovery to some extent.According to Asia grading,in 6 of grade A,1 was restored to B,2 to C,3 had no obvious recovery;1 grade B was restored to C;In 3 cases of grade C,2 were restored to D,1 to E;2 cases of grade D were restored to E.Conclusion:1 Anatomically,the "U" fenestration in the sternal manubrium could approach to T₁ vertebra.2 Clinically,the burst fracture of upper thoracic vertebras(T_1～3) with paralysis could be treated through the "U" fenestration approach in the sternal manubrium.3 The "U" fenestration approach is effective for the burst fracture of upper thoracic vertebras with paralysis.