Unraveling the Mystery of Shoulder Pain #3: Infraspinatus Muscle-Tendon Injuries
Instructor: Ben Benjamin, Ph.D.
Instructor: Ben Benjamin, Ph.D.
1 Webinar Goal
Explore the assessment and treatment of infraspinatus muscle-tendon unit injury.
Logistics • Time: 1 hour
• Schedule: • Presentation 30–40 min • Questions 15–20 min
• Ongoing questions: Use Question box. If I don’t get to your question, ask me on my Dr Ben Benjamin Facebook page after the webinar.
• Get a pen and paper please
Pretest 1. The infraspinatus muscle tendon unit is the primary mover when a. serving in tennis b. hitting backhand c. hitting forehand d. none of the above 2. The infraspinatus muscle tendon unit is usually as strong as strong as the biceps. True or False? 3. When the infraspinatus muscle tendon unit is injured lying on either side is often painful. True or False? 4. The antagonist to the infraspinatus is the: a. supraspinatus b. subscapularis c. teres major and minor d. pectoralis and subscapularis 5. The infraspinatus muscle works with the teres major to laterally rotate the shoulder. True or False?
2 Anatomy
Infraspinatus Muscle-Tendon Unit
Infraspinatus Infraspinatus muscle tendon • Extends from the infraspinous fossa of the scapula to the greater tubercle
Teres minor
Infraspinatus Muscle
• Attached to and covered by the infraspinatus fascia • Infraspinatus fascia separates it from teres major and minor
3 Infraspinatus Tendon
• Glides over the lateral border of the spine of the scapula • Passes over the posterior of the shoulder-joint capsule • Inserts into the greater tubercle • Sometimes separated from shoulder-joint capsule by a bursa
Infraspinatus Function
• Works as external rotator of the glenohumeral joint • Abducts the arm
The Rotator Cuff: Infraspinatus and Teres Minor
• Rotate the head of the Infraspinatus Infraspinatus humerus outward into muscle tendon external rotation • Work together to allow the arm to reach backward • Compared to the teres minor, the infraspinatus is the major external rotator • Infraspinatus is the second Teres minor most often injured rotator cuff muscle
4 Assessment
Assessment Tests
• Resisted lateral rotation • Resisted lateral rotation (30 degrees) • Passive Elevation • Painful Arc • Horizontal Adduction
Resisted Lateral Rotation
5 Resisted Lateral Rotation from 30 Degrees
Passive Elevation
Painful Arc
6 Horizontal Adduction
Theory
Assessment Test Results for the Infraspinatus
• Pain on resisted lateral rotation: infraspinatus is injured
• Other tests tell you injury location
• Other tests are only necessary to do specific scar tissue work
7 Clinical Reasoning Questions
What muscles do you use when:
• Taking off a sweater overhead? • Hitting a ball with a bat? • Reaching to the side (abducting) with your thumb facing down? • Reaching behind you to get something in the back seat of your car? • Grabbing your bag in the backseat and lifting it to the front seat next to you? • Lying on your side in bed?
Opportunity to Test AIS
These were the symptoms I had:
• When I reached into the back seat of my car to get something, it was painful.
• When I was lying on my side, after a while my shoulder began to hurt.
8 Treatment
Friction
Watch the videos at the end of the Webinar
Tendon Injury Exercise Program (TIEP)
Watch the videos at the end of the Webinar
9 TIEP Exercise Therapy
1. Warm up 2. Stretch 3. Strength 4. Stretch 5. Ice
Active Isolated Stretching
Questions
Facebook.com/DrBenBenjamin
10 Post-test 1. The infraspinatus muscle tendon unit is the primary mover when a. serving in tennis b. hitting backhand c. hitting forehand d. none of the above 2. The infraspinatus muscle tendon unit is usually as strong as strong as the biceps. True or False? 3. When the infraspinatus muscle tendon unit is injured lying on either side is often painful. True or False? 4. The antagonist to the infraspinatus is the: a. supraspinatus b. subscapularis c. teres major and minor d. pectoralis and subscapularis 5. The infraspinatus muscle works with the teres major to laterally rotate the shoulder. True or False?
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