Scapular Protraction PDF

# Scapular Protraction ## 1446 H/2024 A.D. ## Manual Muscle Test 200 PHT - Theoretical Part. Jazan University, College of Nursing and Health Sciences, Physical Therapy Department. ### 15th lecture - Theoretical Part: Scapular Protraction **Objectives:** at the end of this lecture the student wi...

# Scapular Protraction ## 1446 H/2024 A.D. ## Manual Muscle Test 200 PHT - Theoretical Part. Jazan University, College of Nursing and Health Sciences, Physical Therapy Department. ### 15th lecture - Theoretical Part: Scapular Protraction **Objectives:** at the end of this lecture the student will be able to: 1. Identify the primary muscles involved in scapular protraction. 2. Identify the range of motion of scapular protraction. 3. Describe effect of weakness of scapular protraction. **Content:** 1. Anatomy of primary muscles involved in scapular protraction. 2. Range of motion of scapular protraction. 3. Effect of weakness of scapular protraction. ### Scapular Protraction Motion (scapular abduction and upward rotation) **Primary Muscles:** 1. Serratus anterior muscle. ### Range of Motion The abduction displacement of the scapula is approximately equivalent to the space of 3 - 4 fingers (Fig. 1). **Figure. 1: Range of motion for scapular protraction.** * A picture of the scapula, with an arrow pointing from the spine to the scapula, labeled Abduction (Protraction). **Limiting factors of range of motion:** 1. Tension of trapezoid ligament (limits forward rotation of scapula upon clavicle). 2. Tension of trapezius and rhomboid major and minor. ### Anatomy of Serratus Anterior muscle. **Origin:** Outer surfaces and superior borders of upper eight or nine ribs. **Insertion:** Costal surface of medial border of scapula (Fig.2). **Nerve supply:** Long thoracic nerve. **Figure. 2: Serratus Anterior.** * A picture of the scapula and surrounding muscles, with the serratus anterior labeled. **Action:** * It abducts, and upward rotates the scapula, so the glenoid cavity faces cranially and holds the medial border of the scapula firmly against the thorax. * The upper fibers of serratus anterior may elevate the scapula slightly. * The lower fibers may depress the scapula. * The serratus anterior acts to displace the thorax posteriorly as the effort is made to push the body away from the wall from a position of 90° flexion of humerus and the hands against a wall (Fig.3). **Figure. 3: Serratus anterior contraction during wall push action.** * A picture of a person pushing against a wall. **Effect of weakness of Serratus anterior:** 1. Weakness or paralysis of Serratus anterior lead to abnormal position of scapula called (winged scapula), in which the shoulder blade, or shoulder bone, protrudes from a person's back (Fig.4) 2. A person's ability to lift, pull, and push weighty objects will be decreased. 3. In some serious cases, the ability to perform activities of daily living such as changing one's clothes and washing one's hair may be difficult. **Figure 4: Winged Scapula.** * A picture of a person with a winged scapula.