극하근"

[문형철]

- 어깨외회전근력 약화로 나타나는 짝힘의 불균형 치료 핵심근육

1. 극하근과 소원근은 손상은 드물지만 어깨 통증이 있을때 흔히 반사성근수축이 일어나면서 근육긴장, Trp가 많이 발생

2. 거의 모든 어깨통증 환자는 어깨의 외회전근력 약화가 나타남.  특히 소원근은 근위축이 흔하게 발생함. 

3. 생체역학적으로 균형있는 어깨내회전과 외회전 힘의 비율 - 어깨 내회전이 100%일때, 어깨 외회전근력은 최소 63%가 되어야 함. 

4. 회회전의 주동근은 극하근과 소원근!!

panic bird...

In human anatomy, the infraspinatus muscle is a thick triangular muscle, which occupies the chief part of the infraspinatous fossa.^[1] As one of the four muscles of the rotator cuff, the main function of the infraspinatus is to externally rotate the humerus and stabilize the shoulder joint.

It attaches medially to the infraspinous fossa of the scapula and laterally to the middle facet of the greater tubercle of the humerus.

The muscle arises by fleshy fibers from the medial two-thirds of the infraspinatous fossa, and by tendinous fibers from the ridges on its surface; it also arises from the infraspinatous fasciawhich covers it, and separates it from the teres major and teres minor.^[1]

The fibers converge to a tendon, which glides over the lateral border of the spine of the scapula, and, passing across the posterior part of the capsule of the shoulder-joint, is inserted into the middle impression on the greater tubercle of the humerus.^[1] The trapezoidal insertion of the infraspinatus onto the humerus is much larger than the equivalent insertion of the supraspinatus, the reason why the infraspinatus is involved in rotarcuff tears about as frequently as the supraspinatus. ^[2]

극하근의 신경지배

The suprascapular nerve innervates the supraspinatus and infraspinatus muscles. These muscles function to abduct and laterally rotate the arm, respectively.

극하근과 소원근의 관계

The infraspinatus is frequently fused with the teres minor.^[3] The infraspinatus is the main external rotator of the shoulder. When the arm is fixed, it abducts the inferior angle of the scapula. Its synergists are teres minor and the deltoid.^[4] The infraspinatus and teres minor rotate the head of the humerus outward (external, or lateral, rotation); they also assist in carrying the arm backward (extension of the glenohumeral joint).^[1] Additionally, the infraspinatus reinforces the capsule of the shoulder joint.^[3]

극하근 Trp 탐구

극하근 건 촉진법

극하근 추나건 사용법

극하근 운동법(어깨 외회전)

에반스의 극하근 isolated stretching

[조상욱]

힘의 비율까지 고려하기엔 너무 어렵겠지만 바른 움직임을 위해선 결국 비율까지도 맞춰줘야겠네요