University:
Stanford University
Course:
MED 101 | Human Anatomy
Academic year:

2023
Views:

459

Pages:

2
Author:

larbi43100

Infraspinatus paralysis ➢The suprascapular nerve, After innervating the supraspinatus,t he suprascapular nerve crosses the spinoglenoid process to innervate the infraspinatus. There are therefore three possible origins of infraspinatus paralysis: . Spinal at the level of the emergence of the nerve (C5-C6) . High scapular when crossing the coracoid notch. . Low scapular when crossing the spino-glenoid procession. Only the last lesion gives isolated paralysis of the subscapularis. ❉ Etiology The exercises responsible for this pathology are repeated retropulsion exercises (wrestling, weightlifting, athletic strength, rugby in the scrum) and falls on the back (judo) or movements of too great an amplitude (bad hammer or javelin throw, Pole vault...). ❉ Diagnosis . Physical examination In very muscular athletes, amyotrophy of the subscapular fossa is evident compared to the opposite side. Conversely, in adolescents or weakly muscular subjects, amyotrophy can be hidden by the latissimus dorsi. The force in external rotation is reduced but it is partly compensated by the teres minor muscle. The supraspinatus is strictly normal. . Complementary exam The electromyogram confirms peripheral damage to the suprascapular nerve at the level of the spinoglenoid process. ❉ Treatment Infraspinatus nerve treatment includes four parts: . Absolute rest of the nerve (shoulder immobilization) intended to avoid friction at the level of its passage at the level of the spine of the scapula. . Starting a muscle maintenance treatment with electrostimulation. . The fight against the inflammatory phenomenon (NSAIDs). As soon as the nervous response has normalized, physiotherapy will be active and intended to restore the region's physiology (proprioceptive re-education). The responsible action will naturally be modified or abandoned. ➢ Supraspinatus paralysis Regarding the innervation of the supraspinatus, the nerve can be damaged at two levels: . At its cervical emergence. . At the level of the coracoid notch. This paralysis is always accompanied by paralysis of the infraspinatus ❉ Etiology Three mechanisms can be attributed to the genesis of this lesion: . Horizontal adduction . Antepulsion with internal rotation of the scapulohumeral . Horizontal retropulsion with external rotation of the shoulder ❉ Diagnosis . ● ● ● Physical examination The symptomatology is dominated by posterior shoulder pain, of which it is most often difficult to discern what is due to the supraspinatus or infraspinatus muscle. Clinical examination may reveal amyotrophy of the supraspinous fossa, but observation and palpation are hampered by the deltoid. The comparative examination of muscular strength is also quite difficult due to compensation by the deltoid for the supraspinatus and the teres minor for the infraspinatus. . Additional tests The diagnosis will be confirmed by the electromyogram, which shows peripheral neurogenic damage whose location will be possible to specify. ❉ Treatment The treatment includes four parts: . ● ● ● ● ● Resting the shoulder . Electrostimulation of the supraspinatus muscle, intended to limit its amyotrophy. . Physiotherapeutic maintenance of the region's muscles and joint range of motion. . The initiation of oral treatment (NSAIDs and vitamin therapy B1-B6). Treatment must be prolonged (two to six months depending on the extent of the neurological damage).