Distribution Of Sensory And Motor Nerves In Rotator Cuff Tendon And Its Clinical Significance

Objective:The main innervation and running of the four tendons of rotator cuff were dissected and studied.To clarify the distribution of sensory nerve endings and motor nerve endings in rotator cuff tendon;The rotator cuff correlation model was established to investigate the distribution and changes of sensory and motor nerve endings in rotator cuff in different rat models.Based on the above research results and other relevant studies,the causes of the corresponding clinical symptoms can be inferred to improve the treatment plan of rotator cuff disease.Methods:This study is designed to be progressive in three parts.The first part is the domination of the rotator cuff main neural anatomy studies: in 6 cases by formalin soaked specimen,the separation of control on the shoulder rotator cuff nerve,scapular nerve and axillary nerve under this article 3 nerve to position into the muscle record three nerve from the length of branch to into the muscle and nerve in the diameter of the important anatomical location,record into a table and analysis.The second part is the dyeing of the fresh shoulder cuff:Into 6 fresh adult corpse,unilateral shoulder line operation complete remove humerus head and adhesion of the subscapularis tendon,supraspinatus tendons tendons,infraspinatus and small circular muscle tendons,in-20 ℃ preservation,for HE,gold chloride,immunofluorescence and immunohistochemical staining,to clear the rotator cuff tendon of sensory nerve endings and motor nerve endings in distribution.The third part was the staining of rat model: standard SD rats were used to establish rotator cuff related models,which were divided into 3 groups: sham operation group,rotator cuff injury group,and rotator cuff reconstruction group.Eight weeks after modeling,the rats were euthanized,and the supraspinatus tendons of the three groups were taken and stored at-20℃ for gold chloride staining to determine the changes of sensory nerve endings in the rotator cuff model of the three groups of rats.Results:(1)Anatomical results of rotator cuff nerve running distribution:A: Observation of the suprascapular nerve: Scapular nerve trunk of brachial plexus on dry,outside the back below the line of the trapezius muscle deep surface,hole on incisure into the shoulder by shoulder,then through the holes into the shoulder on a nest and supraspinatus,supraspinatus branch under the supraspinatus deep facing and nerve trunk by okada jar incisure interiorly to the Vatican to the nest,infraspinatus supported along the musculoskeletal facing down line,Along the way,the joint branches are distributed around the shoulder joint.The length of the suprascapular nerve from the brachial plexus to the suprascapular hole was(45.00±6.86)mm,and the length of the suprascapular nerve from the suprascapular hole to the suprascapular hole was(20.13±4.52)mm.The diameter of the suprascapular nerve from the brachial plexus was(1.49±0.43)mm,the diameter of the suprascapular nerve at the suprascapular hole was(1.40±0.42)mm,and the diameter at the subscapular hole was(1.31±0.41)mm.B: Observation of the subscapular nerve: the subscapular nerve originates from the posterior cord of the brachial plexus,the superior subscapular nerve and the inferior subscapular nerve respectively originate from the posterior cord of the brachial plexus,the superior subscapular nerve passes through the posterior part of the superior axilla and descends to the upper part of the subscapular muscle,and the inferior subscapular nerve enters through the lower part of the axilla and innervates the lower part of the subscapular muscle.The length of the superior subscapular nerve from the brachial plexus to the subscapularis muscle was(43.96±9.51)mm,and the length of the inferior subscapular nerve from the brachial plexus to the subscapularis muscle was(53.92±11.05)mm.The outer diameter of the upper subscapular nerve from the brachial plexus posterior cord was(1.81±0.59)mm,and that of the subscapularis muscle was(1.68±0.54)mm.The outer diameter of the inferior subscapular nerve from the posterior cord of the brachial plexus was(1.92±0.67)mm and to the subscapularis muscle was(1.66±0.55)mm.C: Observation of the branches of the minor teres muscle of the axillary nerve: after the axillary nerve is emitted from the brachial plexus,it enters the posterior tract through the posterior branches of the superior trunk.Walk in the axilla,walk in front of the subscapularis muscle and descend,enter the quadrangular foramen,pass through the quadrangular foramen and reach the lower back of the shoulder joint,then give off the branches of the teres minor,then the lateral margin of the teres minor,and finally give off the branches and supply the muscle.The anterior length of the minor teres branch was about :(16.85±6.79)mm,the diameter of the minor teres branch was about :(1.40±0.53)mm when it originated,and the diameter of the minor teres branch was about :(1.42±0.52)mm when it entered the muscle.(2)Dyeing results of human fresh shoulder cuff:A: There are different number of sensory nerve endings in different positions of the four tendons of rotator cuff.The number of free nerve endings in all tendons of rotator cuff is the largest,followed by Pacinian corpulla and Ruffini corpulla.Golgi tendon organs are rarely found in tendons and mainly exist at the junction between tendons and muscles.B: The number of sensory nerve endings in the four rotator cuff tendons in descending order is subscapularis tendon,supraspinatus tendon,infraspinatus tendon and teres minor tendon.C: In all tendons,the number of sensory nerve endings near the joint surface is more,the number of sensory nerve endings in the middle layer is less,and finally the number of sensory nerve endings in the distal joint surface layer of the bursa layer will increase.D: The application of modified gold chloride did not stain the motor endplate at all tendon sites(occasionally considered as experimental error),but a small amount of staining of the motor endplate at the tendon-muscle junction was possible.There were more and stronger k-R staining results in muscles,but no positive results in rotator cuff tendons(the occasional results were considered as experimental errors).There were a few positive results at the junction of muscle and tendon,indicating that motor nerve fibers were widely distributed in muscles,while there was no distribution of motor nerve endings in tendon positions.In general,k-R staining results of the four tendons were more frequent when they were near the muscle-tendon junction,while there were no positive results in the pure tendon position of all sections.(3)Staining results of rats in the three groups:A:Rotator cuff injury in rats: A model of the supraspinatus tendon atrophy,supraspinatus tendons within the typical receptor number decreased significantly,some typical receptor morphological changes(atrophy or within the structure disorder),the number of irregular structure of the sensor will be increased,and the total number of receptor(including four typical kinds of sensors and the structure of the irregular)decreased significantly.B: The supraspinatus tendon in the rat rotator cuff injury repair model healed well,and the number of supraspinatus tendon receptors in the rat rotator cuff injury reconstruction model was more than that in the rat injury model.Conclusion:(1)Muscular innervation: the supraspinatus and infraspinatus are mainly innervated by the supraspinatus nerve from the superior trunk of the brachial plexus,the subscapularis muscle is mainly innervated by the superior subscapular nerve and the inferior subscapular nerve from the posterior cord of the brachial plexus,and both of these two nerves have the probability to branch,and the teres minor is mainly innervated by the teres minor branch of the axillary nerve.(2)The distribution of sensory nerve endings: the number of free nerve endings in all tendons of rotator cuff is the largest,followed by Pacinian cordillera and Ruffini cordillera,Golgi tendon organs are less in tendon,mainly exist in the junction of tendon and muscle;The number of sensory nerve endings in four rotator cuff tendons in descending order were subscapularis tendon,supraspinatus tendon,infraspinatus tendon and teres minor tendon.(3)Distribution law of motor nerve endings: human rotator cuff tendon is only distributed at the junction of muscle and tendon,and there is no motor nerve endings in other positions,proving that rotator cuff can only transmit sensory signals,not electrical signals causing contraction.(4)After tendon injury of supraspinatus muscle in rats,the number of sensory nerve endings in tendon will decrease,and the structure will atrophy and destruction,etc.Surgery can improve the changes of sensory nerve endings.Meaning:(1)To clarify the general distribution of sensory and motor nerves in the rotator cuff can explain,to a certain extent,the more serious symptoms of subscapularis tendon injury and supraspinatus tendon injury,and the difficulty to detect the internal tendon tear.(2)The distribution area of different types of sensory and motor nerve endings can be defined,and the low-distribution area of sensory nerve can be selected for operation during the operation to protect the structure of the proximal joint capsule,which can optimize the intraoperative surgical location and improve the prognosis.(3)It can provide a certain anatomical basis for the selection of nerve problems in denervation operation.(4)Rat experiments have proved that patients with rotator cuff injury will have a large number of abnormal sensory nerve endings without treatment for a long time.Surgical treatment is recommended when the symptoms are more serious,which can make certain recovery of the sensory nerve endings.