Rotator cuff interval - Anatomy

Rotator cuff interval
Triangular shape. Bordered by:
1. Coracoid process
2. Subscapularis muscle/tendon (SSc)
3. Supraspinatus muscle/tendon (SSp)

Houses:
1. (Intra-articular portion of) Long head of biceps tendon (LHBT)
2. Coracohumeral ligament (CHL) (superficial)
     - Variants: absent CHL
     - Originate from postero-lateral of coracoid process
3. Superior glenohumeral ligament (SGHL) (deep)
     - Variants: absent SGHL

Important structures:
1. Medial-pulley-complex (MPC)
     - Medial bundle of CHL + SSc + SGHL
     - Medial to the LHBT
     *Disruption causes subluxation of the LHBT medially

2. Lateral-pulley-complex (LPC)
     - Lateral bundle of CHL + SSp
     - Lateral to the LHBT

3. Rotator cable (part of lateral-pulley-complex)
     - Suspense and stabilise the shoulder joint
     - Thin fibrous band extension from CHL and some of SGHL
     - Traverse deep to SSp and ISp, superficial to joint capsule

4. Capsulo-ligamentous biceps pulley / Superior-complex layer (SCL)
     - CHL + SGHL + Capsule
     - Forms the roof of intra-articular portion of LHBT (proximal to the transverse humeral ligament)

5. Rotator crescent
     - An area between rotator cable and the SSp insertion
     - Poorly vascularised area
     - Gets thinner with age




Reference: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5568533/