Anatomical And Biomechanical Study Of Tendon Fixation Of Long Head Of Biceps Brachii

Part 1 anatomical study on the fixation of the long head tendon of biceps brachiiObjective: By studying the anatomy of the fixation of LHBT(long head of the biceps brachii tendon),the anatomic characteristics of the fixation points of LHBT were analyzed to provide anatomic basis for the appropriate fixation points of clinical LHBT.Methods: 24 fresh adult cadavers of shoulder joint were dissected layer by layer.After exposing LHBT and its adjacent muscles and tendons,the starting point a of the supraglenoid node of LHBT,the capsule point B of the exit joint,the lower edge point C of the small node,the upper edge point D of the pectoralis major muscle,the junction point e of the muscle and tendon,the lower edge point F of the pectoralis major muscle were marked respectively.The length of AB,AC,ad,AE and AF were measured with vernier caliper.The points B,C,D,e and F were measured with silk thread and ruler Tendon diameter.Results: The length ab of intraarticular LHBT was 21.25~35.58 mm,with an average of(29.95±5.11mm).The length from the starting point of LHBT to the lower edge of the small nodule was 43.25~67.56 mm,with an average of(54.86±5.41)mm;the length from the upper edge of the pectoralis major muscle was 69.65~92.82 mm,with an average of(82.17±6.24)mm;the length from the lower edge of the small nodule to the muscle tendon was 90.78~125.46 mm,with an average of(104.17±8.98)mm;the length from the lower edge of the small nodule to the pectoralis major muscle was 99.34~139.44 mm,with an average of(117.24±16.17)mm;the length from the lower edge of the small nodule to the pectoralis major muscle was The length CD of the upper edge is 25.69~34.67 mm,with an average of(27.29±3.87)mm.The diameter of LHBT tendon in point B was about 5.75~6.84 mm,with an average of(6.30±4.33)mm;the diameter of LHBT tendon in point C was about 5.25~6.67 mm,with an average of(6.03±0.50)mm;the diameter of LHBT tendon in point D was about 5.05~6.34 mm,with an average of(5.99±0.62)mm;the diameter of LHBT tendon in point e was about 5.45-6.79 mm,with an average of(5.99±0.63)mm;the diameter of LHBT tendon in point F was about 8.55~10.86 mm,with an average of(10.16±0.98)mm.In the length of LHBT,there were significant differences between AB and AC,ad,AE,AF(P < 0.05).In the diameter of LHBT tendon,there was no significant difference between point B and C,D,E(P > 0.05),but there was significant difference between point B and F(P < 0.05).Conclusion: LHBT is an important tendon of pronation in flexion of shoulder,elbow and forearm.It passes through the groove between nodules in a certain arc after passing through the joint capsule,and then through the pectoralis major muscle area.When LHBT tendon fixation is performed,if it exceeds the upper border of pectoralis major muscle,it may reach or even exceed the junction of muscle and tendon,affecting the fixation effect.Part 2 A comparative study on biomechanics of tendon fixation of long head tendon of biceps brachii with 3-suture and anchor nailObjective: To compare the biomechanical properties of different methods(3-suture anchor,tendon suture,compression screw)and different positions(proximal and distal)of the compression screw in LHBT fixation,so as to provide the biomechanical theoretical support for the selection of the methods and positions of LHBT fixation.Methods: Using 24 fresh frozen human shoulder joint cadaver specimens,the skin and muscles were removed layer by layer,the inter nodal groove and the small tubercle of humerus were exposed,part of the joint capsule and pectoralis major muscle were preserved first,the joint capsule,the lower edge of the small tubercle of humerus,the upper edge of the pectoralis major muscle and the lower edge of the pectoralis major muscle were marked on the humerus,the LHBT was dissociated,and the soft tissues such as the upper muscle and blood vessels of humerus were repaired and cleaned up.In this process Care should be taken to avoid damaging bone markers.The repaired specimens were randomly divided into three groups: the proximal 3-suture anchor group,the proximal extrusion screw group,and the distal extrusion screw group.The tendon fixation positions of the proximal 3-suture anchor group and the proximal extrusion screw group were at the junction of the left capsule and the LHBT nodal groove,and the muscle of the distal extrusion screw group The tendon was fixed 20 mm below the tubercle.Adjust the specimen clamp so that the tension applied to each specimen by the biomechanical machine is parallel to the longitudinal axis of the humerus.The preload of small range(5N)is applied for 2 minutes first,then from 5N to 100 N after preloading,and the cyclic loading is 500 times at the frequency of 1 Hz;finally,the load failure test is carried out at 1 mm / s.Three groups of cyclic displacement,stiffness,failure load,failure displacement and failure mode were recorded.There were significant differences between the three groups(P < 0.05).Results: There was no significant difference in ultimate failure load and stiffness between the proximal 3-suture anchor group and the proximal compression screw group(P > 0.05).However,the circulation displacement(P = 0.009)and destruction displacement(P = 0.027)of the proximal 3-suture anchor were significantly higher than those of the proximal compression screw.There was no significant difference in ultimate failure load and stiffness between the two groups(P > 0.05).However,the cyclic displacement(P = 0.000)and destructive displacement(P = 0.005)of the proximal compression screw fixation were significantly higher than those of the distal compression screw fixation.In the 3-suture group,the failure modes included 5 anchor pulling out and 3 LHBT tendon tearing,while in the compression screw fixation group,the failure modes of all specimens were LHBT tendon tearing,with significant differences between the two groups.Conclusion: There are equivalent ultimate failure load and rigidity between the technique of tendon suture LHBT with 3-suture anchor and the technique of extrusion screw LHBT,but in the study of cadaver biomechanics,the technique of tendon suture LHBT with 3-suture anchor shows greater cyclic displacement and failure displacement.With the change of the fixation position at the far and near end,the near end of extrusion screw LHBT has greater damage than the far end Displacement values.From the perspective of biomechanics,it is a very good technique for the fixation of LHBT on the pectoralis major muscle by tendon suture with 3-suture anchor.