2AXILLARY NERVEA large nerve arising from the posterior cord of the brachial plexusDivided:Posterior branch: Innervates Teres minor, part of the Deltoideus&Anterior branch. Innervates Skin overlying the Deltoideus; the Deltoideus. (Some fibers of the nerve also supply the capsule of the shoulder joint)
3AetiologyBlunt trauma or excessive stress on the nerve over a long period of timeother body structures putting pressure on the axillary nerve, or trapping it against another body parta penetrating injury, such as a knife or gunshot woundexceeding a normal range of motion joint.high-impact upper body activities (athletes)perform repetitive tasks using your shoulderhave a certain type of existing bone fractureimproperly use supportive equipment such as crutches
4Pathophysiologymost common peripheral nerve injury to affect the shoulder.It most often is seen after glenohumeral joint dislocation, proximal humerus fracture, or a direct blow to the deltoid muscle.Compression neuropathy has been reported to occur in the quadrilateral space syndrome,true pathophysiology of this disorder remains unclear.vulnerable during any operative procedure involving the inferior aspect of the shoulder and iatrogenic injury (Referring to injuries caused by a doctor.).
5The quadrangular space (or quadrilateralspace or Foramen Humerotricipitale) is an axillary space in the arm.This is a clinically important anatomic space in the arm.Pathophysiologymost common peripheral nerve injury to affect the shoulder.It most often is seen after glenohumeral joint dislocation, proximal humerus fracture, or a direct blow to the deltoid muscle.Compression neuropathy has been reported to occur in the quadrilateral space syndrome, although the true pathophysiology of this disorder remains unclear. The axillary nerve is vulnerable during any operative procedure involving the inferior aspect of the shoulder and iatrogenic injury remains a serious complication of shoulder surgery. During the acute phase of injury, the shoulder should be rested, and when clinically indicated, a patient should undergo an extensive rehabilitation program emphasizing range of motion and strengthening of the shoulder girdle muscles. If no axillary nerve recovery is observed by 3 to 6 months after injury, surgical exploration may be indicated, especially if the mechanism of injury is consistent with nerve rupture. Patients who sustain injury to the axillary nerve have a variable prognosis for nerve recovery although return of function of the involved shoulder typically is good to excellent, depending on associated ligamentous or bony injury.
6Pathophysiology Seddon's Classification of Nerve Injury Nerve regeneration takes place at a rate of ~1mm/daySeddon's Classification of Nerve InjuryNeuropraxia The axon and all 3 connective tissue layers (endoneurium, perineurium, and epineurium) remain intact with a decrease in conductionAxonotmesis Axonal damage is present with preservation of the endoneuriumNeurotmesis Axonal damage is present
7PathophysiologyAnterior shoulder dislocation is the most common occurring dislocation at the shoulder.Men and women 3:1 9-65% involve axillary nerve injuryTraction and compression to the axillary nerveBlunt trauma
8Clinical Presentation # Variable and can go undetected, as the concomitant dislocation or fracture may mask the symptoms. Subjective ExaminationGeneralized mild, dull, and achy pain to the deep or lateral shoulder, with occasional radiation to the proximal armNumbness and tingling of the lateral arm and/or posterior aspect of the shoulder In some cases, persisting 2-4 weeks post-injuryFeeling of instability
9Clinical Presentation Weakness, especially with flexion, abduction, and external rotation Fatigue, especially with overhead activities, heavy lifting, and/or throwing May/or may not reveal a history of trauma to the shoulder regionEasing Factors include: rest, ice, analgesics, and anti-inflammatory medications
10Clinical Presentation Differential Diagnosis“Unhappy Triad”Quadrilateral Space Syndrome (QSS) Posterior Cord of the Brachial Plexus InjuryC5-6 Cervical RadiculopathyParsonage-Turner Syndrome (PTS)"Unhappy Triad"The “Unhappy Triad” consists of a shoulder dislocation that results in both a rotator cuff tear and axillary nerve injury.Occurs in 9-18% of anterior shoulder dislocationsRisk of an “unhappy triad” with anterior shoulder dislocation increases after the age of 40.
11Clinical Presentation Quadrilateral space syndrome(QSS)QSS is an “uncommon condition that involves the compression of the posterior humeral circumflex artery and the axillary nerve within the quadrilateral space,” secondary to an acute trauma or from overuse, especially with overhead sports like throwing and swimming.Symptoms are typically present with the arm in an overhead position, especially in late cocking or the early acceleration phases of throwingParsonage-Turner Syndrome(PTS)PTS is an uncommon, idiopathic condition.Characterized by an acute onset of intense pain, without a mechanism of injury, that subsides within days-weeks, leaving behind residual weakness/paralysis in upper extremity muscles.
13Symptoms Numbness over part of the outer shoulder Shoulder weakness, especially when lifting the arm up and away from the bodyMay experience weakness in the shoulders and have problems with normal physical activities, such as lifting your arms above your head. Difficulty lifting objects can also be a sign of AND.Over time, your shoulder muscles may become smaller because they cannot be worked out regularly.
14Medical Management Examination Physical examination should begin with a screening consisting of an evaluation of the head and neck which shouldn’t reveal any abnormalities.If the patient presents with a recent shoulder dislocation, presence of a radial pulse and sensation and movement of the digits should also be assessed as part of the initial screening
15Medical Management Nonsurgical Reduction Surgery Reduction eliminates the need for surgical intervention, and is followed by immobilization and physical therapy management.Immobilization for young adult males 4-6 weeksImmobilization for older patients 7-10 days Precaution should be taken during manipulative reduction of a dislocation,NSAIDS, rest, ice SurgeryIndications for surgerySuspicion of osteophyte formation or compression in the quadrilateral space.No axillary nerve recovery observed by 3 to 4 months following injury.No improvements seen after 3 to 6 months of conservative treatment.No EMG/NCV evidence of recovery by 3 to 6 months after injury.Surgical ProceduresNeurolysisNeurorrhaphyNerve grafting
16Physical Therapy Management (current best evidence) Current research encompassing treatment and intervention of axillary nerve injuries following shoulder dislocation is limited.Non-Surgical Physical Therapy Treatment0-2 weeksShoulder immobilization via sling after reductionThere is insufficient evidence to support whether physical therapy should be initiated during or after immobilization. Isometric Strengthening; Dosing: 10 seconds X 6 repetitions X 2 day within limits of painShoulder(Flex, Ext, Abd, Add, IR)Joint MobilityActive Range of Motion(AROM); Dosing 10 repetitions X 2 dayElbow(Flex, Ext ,Pronation, Supination)Wrist (Flex, Ext, Radial/Ulnar deviation)Hand (Opening/Closing Fist)
172-4 weekJoint MobilityPROM/AAROM); Dosing 10 repetitions X 2 day Shoulder (Flex, IR, Add)Avoid end-range ER/Abd until later stages of treatment!AROM; Dosing 10 repetitions X 2 dayElbow(Flex, Ext ,Pronation, Supination) Wrist (Flex, Ext, Radial/Ulnar deviation) Hand (Opening/Closing Fist)Pendulum Exercises 3 sets x 30 secondsPostural/Periscapular Muscular Strengthening/Neuromuscular Re-educationTarget MusclesDeltoid Serratus AnteriorRhomboid Major/Minor Upper/Middle/Lower TrapeziumPRECAUTION: against shoulder abduction & flexion beyond 90 degrees, and ER beyond neutral in the first 3 weeksOlder individuals have lower rates of reoccurrence of shoulder dislocation and an increase in incidence of joint stiffness.
18Medical Management 4-6 weeks D/C sling Strengthening Program light resistive exercises Proprioceptive TechniquesPNF diagonalsClosed Chained ActivitiesWall push-ups -->Table-->FloorWeight Shifts6 weeks-Discharge Continue ROM, glenohumeral and scapulothoracic stabilization/strengthening exercises,Proprioception, and joint mobility, while maintaining optimal conditions for tissue healingBegin to initiate sport/job specific activities, progressing to full return as patient’s functional status allowsMedical Management
19ConclusionDuring the acute phase of injury, the shoulder should be rested, and when clinically indicated, a patient should undergo an extensive rehabilitation program emphasizing range of motion and strengthening of the shoulder girdle muscles.If no axillary nerve recovery is observed by 3 to 6 months after injury, surgical exploration may be indicated, especially if the mechanism of injury is consistent with nerve rupture.Patients who sustain injury to the axillary nerve have a variable prognosis for nerve recovery although return of function of the involved shoulder typically is good to excellent, depending on associated ligamentous or bony injury.