Injuries of Pectoral, Scapular and deltoid regions

1. Absence of Pectoral Muscles- Pec major absent (sternocostal part)- No disability- Anterior axillary fold (skin and fascia overlying inferior boarder of pec major) absent

nipple > inferior than usual

Poland syndrome: (3)

Pec maj and minor absent Breast hypoplasia (underdevelopment) Absence of 2- 4 rib segments

2. Paralysis of serratus anterior a. Result: Long thoracic nerve injury Winged Scapular

i. Wing Appearance of Scapular1. Medial boarder of scapular moves laterally and posteriorly away

from thoracic wall (Person leans on hand/ presses UL against wall)ii. Winged Scapular Deformity

1. Medial boarder and inferior angle of scapular pull markedly away from posterior thoracic wall

iii. No complete abduction (UL cannot abduct above horizontal position)1. serratus ant cant rotate glenoid cavity superiorly 2. Trapezius helps raise arm above horizontal position

b. At risk:i. Knife stab, bullet shot in thorax (Long thoracic nerve courses superficial

aspect of serratus anterior)

3. Injury of spinal accessory nerve (CN XI)a. Result: Spinal Accessory Nerve Palsy

i. Ipsilateral (on one side) weakness when shoulders shrugged/elevated against resistance

4. Injury of Thoracodorsal Nerve (C5-C8) – passes inferiorly along posterior wall of axilla, enters medial surface of lat dorsi

a. Result: Paralysis of latissimus dorsi (primary activities where active depression of scapular is required) (passive depression provided by gravity is adequate for most activities)

i. Unable to raise trunk w UL eg during climbingii. Cannot use axillary crutch (shoulder pushed superiorly by lat dorssi)

b. At Risk:i. Surgery in inferior part of axilla

ii. Mastectomies when axillary tail of the breast is removediii. Surgery on scapular lymph nodes (terminal part of nerve lies anterior to

lymph nodes and subscap artery)

5. Injury to Dorsal Scapular Nerve- innervates rhomboidsa. Result: Paralysis of Rhomboid(s)

i. Scapular on affected side located farther from midline than that on normal side

6. Injury to Axillary Nerve (C5-C6) – passes inferior to humeral head and winds around surgical neck of humerus, runs transversely under cover of deltoid (common site for intramuscular injections of drugs) at level of surgical neck of humerus (awareness of location avoids injury to it during surgical approaches)

a. Result: i. Deltoid Atrophies

1. Presenting sign: Rounded contour of shoulder flattened as compared to uninjured side slight hollow inferior to acromion

ii. Loss of sensation over lateral side of proximal arm (Regimental Patch)1. area supplied by superior lateral cutaneous nerve of arm (the

cutaneous branch of axillary nerve)b. At Risk:

i. Fracture at Surgical Neck of Humerusii. Dislocation of Glenohumeral Joint

iii. Compression from incorrect use of crutches

7. Fracture- Dislocation of Proximal Humeral Epiphysisa. In severe fractures:

i. Shaft of humerus markedly displacedii. Humeral head retains normal relationship with glenoid cavity

b. Cause/ At Risk:i. Direct blow / indirect injury of shoulder of child

1. Tendons of STIS rotator cuff muscles stronger than epiphysial plate (Joint capsule of glenohumeral joint reinforced by rotator cuff muscles)

8. Rotator Cuff Injuries (SEE “DISLOCATION OF GLENOHUMERAL JOINT”)a. Cause:

i. Injury/ disease damage musculotendinous rotator cuffb. Result:

i. Instability of glenohumeral jointii. Rupture/tear of 1/> SITS tendons (due to trauma) *supraspinatus tendon

most commonly rupturediii. Degenerative Tendonitis of rotator cuff (Common in older ppl)

9. Triangle Of Auscultationa. Small triangular gap in musculature near inferior angle of scapularb. Formed by:

i. Superior horizontal boarder of lat dorsiii. Medial boarder of scapular

iii. Inferolateral boarder of trapeziusc. Clinical significance:

i. Gd place to examine posterior segments of lungs w stethoscopeii. When:

1. Scapulae are drawn anteriorly (arms folded across chest) 2. Trunk is flexed 3. 1. + 2. Triangle of Auscultation enlarges and parts of 6th and 7th

ribs and 6th intercostal space are subcutaneous