Shoulder complex consists of following joints
1) Shoulder joint
2) AC Joint
3) SC Joint
4) Scapulothoracic joint.
All 4 joints work in concomittant and coordinated fashion so as to produce efficient movement at shoulder.
Shoulder complex has got direct impact on cervical, thoracic and lumbar spine and vice versa.
Considering the complex relationship, if any of the shoulder complex or spine movement gets impaired due to weak or tight muscles it leads to imbalance in the whole system.
This imbalance leads to improper functioning of shoulder leading to “Shoulder Dysfunction”