Course Instructor (P19)
Common Trigger Point Areas
1) Upper Trapezius Muscle
The upper fibers originate above the superior nuchal line, the ligamentum nuchae, and spinous process of C1 through C5. Inserting on the spine of the scapula, the acromion and the lateral 1/3 of the clavicle. The upper trapezius is innervated by the spinal accessory nerve (CN XI, motor) and the 3rd and 4th cervical nerves (sensory). The upper trapezius muscle fibers raise the shoulder. Upper trapezius muscle Trigger Points (TP’s) are commonly activated by whiplash and/or repetitive overload.
a) Rhomboid Minor – origin is at the ligamentum nuchae and the spinous processes of the C7 and T1 vertebrae. Insertion is the medical border of the scapula.
b) Rhomboid Major – origin is at the spinous processes of T2 to T5 vertebrae and it inserts at the medial border of the scapula between its spine and its inferior angle.
- These muscles are innervated by the Dorsal Scapula nerve (C5 nerve root). They adduct and elevate the scapula and hold the lower angle of the scapula close to the ribs preventing winging.
- Prolonged Rhomboid Trigger Points can cause rounded shoulders and refer pain to the scapula and the the Supraspinatus muscle. These TP’s are activated by prolonged forward bending in the round shoulder position and by upper thoracic scoliosis.
- Rhomboid ‘TP’s are usually found along the medial border of the scapula. Compress them for approximately 1 minute.
3) Supraspinatous Muscle
- The Supraspinatous muscle originates at the medial Supraspinatus fossa and attaches laterally to the upper part of the greater tubercle of the humerus. It is innervated by the suprascapula nerve from the C5 spinal root.
- The supraspinatus muscle strengthens the shoulder joint by drawing the humerus toward the glenoid fossa and it assists in abduction of the arm.
- Supraspinatus T.P.’s can refer pain into the lateral epicondyle of the elbow.
- The Infraspinatous muscle originates in the Infraspinatus fossa, extends laterally and inserts into the greater tuberosity of the humerus. It is innervated by the Suprascapula nerve arising from the 5th and 6th cervical nerves. This muscle helps to stabilize the shoulder joint by holding the head of the humerus in the glenoid fossa and is involved in external rotation of the arm at the shoulder.
- Infraspinatus trigger points may cause an inability to internally rotate and adduct the arm at the same time. Visualize an individual not being able to reach into their back pocket.
- Referred pain from these TP’s is found in the front of the shoulder joint and down the arm.
- The trigger points are activated by frequent overload stress where the patient must reach out and back repetitively.
5) Teres Minor
- The Teres Minor muscle originates at the dorsal surface of the scapula near its axillary border and inserts at the greater tubercle of the humerus. It is innervated by the axillary nerve which contains fibers from the 5th cervical root.
- The Teres Minor muscle will stabilize the shoulder joint by holding the head of the humerus in the glenoid fossa and also helps to externally rotate the arm at the shoulder joint.
- The teres minor will refer pain to the deltoid muscle.
- Teres Minor TP’s will be found in the area of the arm crease.