Chapter 11: The Shoulder and Upper Arm

EDUCATIONAL OBJECTIVES

The learner should, at the completion of the chapter, be able to perform the following:

ANATOMY

The shoulder girdle is one of the most mobile anatomical structures in the body. The shoulder girdle moves in multiple directions, allowing the upper arm to assume an unlimited number of positions. Naturally, whatever position the shoulder and upper arm assume is yet another position in which they can become injured. The shoulder girdle gains its mobility at the expense of stability. This chapter focuses on two types of athletic injuries to the shoulder and upper arm; those caused by direct and indirect trauma.

The shoulder and upper arm is made up of these four bones: sternum, clavicle, humerus, and scapula. The four joint of the shoulder girdle are the sternoclavicular (SC), acromioclavicular (AC), coracoclavicular (CC), and glenohumeral (GH). The sternum is located on the anterior portion of the body and provides attachment to the clavicle at the SC joint. The SC joint attaches the upper extremity to the torso. The clavicle supports the shoulder complex on the front of the body. There is no muscle or fat covering this bone, so it is easy to feel along its s-shaped length. Distally on the clavicle, you may be able to feel a projection. This is the point where the clavicle articulates with a part of the scapula known as the acromion process forming the AC joint. Through the coracoclavicular ligaments, the articulation joins the clavicle with the scapula to form the coracoid process, a bony protusion on the anterior aspect of the scapula. These two bones are attached in both places by ligaments to form the CC joint. The clavicle does not articulate with the humerus on the distal aspect but attaches to the proximal aspect of the sternum, to form the SC joint.

The humerus is the long bone of the upper arm. The skeletal articulation of the humerus and the scapula is structurally weak, but very mobile. This joint, the GH joint, is similar to the hip joint except that the socket is very shallow, allowing for greater movement. The range of motion of the gleniod humeral joint is complex and allows for movement in all planes. The scapula, which "floats" on the back of the rib cage, has two small, hooked projections, the acromion process and the coracoid process. The scapula, through its muscular attachment to the torso and humerus, has a scapularhumeral movement/rhythm that allows these anatomical structures to move effectively. Another section of the scapula is called the glenoid fossa, a shallow socket or cup on the lateral side of the scapula. This depression articulates with the spherical head of the humerus and is called the glenohumeral joint. The primary ligaments of the shoulder complex allow for the tremendous mobility and movement associated with this region of the body. The strength and integrity of these structures, in conjunction with the muscles, account for the majority of the stability of the complex.

Like the muscular structure around the knee, the muscles that cross the shoulder's glenoid humeral joint add stability to the weak bony structure. These muscles include the deltoid, pectoralis major, biceps, triceps, latissimus dorsi, trapezius, and the rotator cuff muscle group. The rotator cuff muscle group includes the supraspinatus, infraspinatus, teres minor, and subscapularis, commonly referred to as SITS. The muscles of the shoulder assist with the stability, movement, and strength to this complex anatomical area. The shoulder complex must be strong in order for the athlete to effectively participate in those sports that demand throwing as part of the game.

This area of the body is innervated by a number of different nerves. The sensory distribution of a nerve root is called a dermatome, which produces feeling in a certain anatomical area. The motor distribution of a group of muscles innervated by a single nerve root is called a mytome and it produces movement of anatomical structures. Additionally anatomical structures in the shoulder girdle that are often injured are the bursi. The bursae are closed, fluid-filled sacs that serve as cushions against friction over a prominent bone, or where a tendon moves over a bone.

SHOULDER AND UPPER ARM ANATOMY

Bones

  1. Sternum
  2. Clavicle
  3. Scapula
  4. Humerus
Ligaments
  1. Costoclavicular
  2. Acromioclavicular
  3. Coracoclavicular
  4. Acromion
  5. Sternoclavicular
  6. Glenohumeral
Joints
  1. Glenohumeral (GH)
  2. Acromioclavicular (AC)
  3. Sternoclavicular (SC)
  4. Coracoclavicular (CC)
Range of Motion: Shoulder Joint

Flexion
Extension
Abduction
Adduction
Horizontal Abduction
Horizontal Adduction
Internal and External Rotation--with arm at the side of the body and with the arm abducted to 90 degrees
Circumduction
Elevation
Depression
Protraction
Retraction

Muscles and Functions

  1. Deltoid - abduction, flexion, internal and external rotation of arm
  2. Biceps - flexion and supination of arm
  3. Triceps - extends forearm and upper arm
  4. Coracobrachialis - adduction; assists in flexion and pronation of the arm.
  5. Supraspinatus - assists in abducting arm (Rotator Cuff)
  6. Infraspinatus - external rotation (Rotator Cuff)
  7. Teres minor - external rotation (Rotator Cuff)
  8. Subscapularis - internal rotation of shoulder (Rotator Cuff)
  9. Rhomboids - retraction and rotation of the scapula
  10. Pectoralis Major - flexes upper arm; adducts arm anteriorly, internal rotation
  11. Pectoralis Minor - raises ribs for inspiration, draws scapula forward and downward
  12. Latissimus Dorsi - extends arm; adducts arm posteriorly, internal rotation, downward rotation of scapula
  13. Levator Scapulae - elevates scapula, extends and lateral flexion of neck, assists with downward rotation of scapula
  14. Serratus Anterior - Rotates scapula for abduction and flexion of arm, protracts scapula
  15. Teres Major - Assists in extension, adduction, and internal rotation of arm
  16. Trapezius - Retraction, upward rotation, elevates scapula, and downward rotation of scapula
Dermatomes

C4 - Upper chest across the clavicle
C5 - The skin and the lateral aspect of the arm over the insertion of the deltoid muscle
C6 - The bicep muscle lateral to the base of the thumb
C7 - The tricep muscle with distribution to the second and third fingers
C8 - Intrinsic muscle with distribution to the fourth and fifth fingers
T1 - Medial aspect of forearm
T2 - Across upper chest above the nipples
T3 - Across upper chest above the nipples
T4 - At the nipples
T5 - Across the abdomen
T6 - Across the abdomen
T7 - Across the sternal notch
T8 - Across the abdomen, supplies motor function for abdominal muscle contraction
T9 - Across the abdomen; supplies motor function for abdominal muscle contraction
T10 - Umbilicus
T11 - Below Umbilicus
T12 - Just below groin

Myotomes

C4 - Shoulder Shrugs
C5 - Abduction Test of the Arms
C6 - Wrist Extension
C7 - Triceps (Extension)
C8 - Finger Flexion
T1 - Finger Abduction

When testing, resistive technique should be used to determine strength of myotome.

EVALUATION FORMAT

The first purpose of an evaluation is to determine if a serious injury has occurred. The evaluation format of History, Observation, Palpation and Special Tests is thoroughly covered in Chapter 2 and Chapter 6. Listed below is an abbreviated version of this format.

History: Questions should include mechanism of injury, location of pain, sensations experienced, and previous injury.

Observation: Compare the uninjured to the injured upper extremity and look for bleeding, deformity, swelling, discoloration, scars, and other signs of trauma.

Palpation: Using bilateral comparison, palpate neurological, circulatory, and anatomical structures, and assess for potential fractures.

Special Tests: Special tests assess disability to ligament, muscle, tendon, accessory anatomical structures, inflammatory conditions, range of motion, and pain or weakness in affected area. These tests are well beyond the expertise of a student athletic trainer.

ASSESSMENT TESTS

The purpose of a thorough evaluation is to enable the allied health professional to properly assess the severity of the injury and to make recommendations regarding treatment and possible return to participation. Listed below is a review of evaluation techniques utilized by certified athletic trainers. For further information, the learner should consult chapter references for a comprehensive description of evaluation techniques.

Glenohumeral Joint Stability Tests

Apprehension: detects anterior shoulder subluxation or dislocation
Relocation: detects chronic anterior dislocation of the glenohumeral joint
Anterior Instability: detects anterior instability of the glenohumeral joint
Anterior/Posterior Translation: assesses anterior/posterior joint laxity
Posterior Glenohumeral Instability: assesses humeral head posterior subluxation
Inferior Drawer or Feagin: assesses humeral head inferior subluxation

Rotator Cuff Impingement Tests

Full Flexion: assesses the presence of rotator cuff inflammation or impingement
Flexion-internal rotation: assesses the presence of rotator cuff inflammation or impingement

Rotator Cuff Muscular Strength Tests

Supraspinatus Strength (empty can test): assesses the strength of the supraspinatus muscle
Internal Rotation Strength: assesses the strength of the subscapularis muscle
External Rotation Strength: assesses the the strength of the infraspinatus and teres minor muscles

Internal Derangement Test

Glenoid Labrum Clunk: assesses the glenoid labrum's integrity and stability

Acromioclavicular Joint Tests

Acromioclavicular Joint Stability: assesses the integrity of the acromioclavicular and coracoclavicular ligaments
Cross Chest or Horizontal Adduction: assesses acromioclavicular joint impingement

Sternoclavicular Joint Test

Sternoclavicular Joint Integrity: assesses the sternoclavicular and costoclavicular ligaments' integrity

CONDITIONS THAT INDICATE AN ATHLETE SHOULD BE REFERRED FOR PHYSICIAN EVALUATION:

COMMON INJURIES

Fractures: Fractures to the clavicle, humerus, scapula, and sternum can occur from a direct blow or indirect trauma (falling on an outstretched arm). In the latter case, the force is transmitted directly to all four shoulder joints, causing a mechanism of injury. The clavicle is commonly fractured in the middle third of the bone, usually resulting from a direct blow. Unlike the clavicle, the proximal end of the humerus is covered by a good deal of soft tissue. Therefore, with a fracture to the humerus in the shoulder area, the athletic trainer may not notice the obvious deformity found with a fractured clavicle. Fractures and dislocations of the head of the humerus should be treated as medical emergencies, because of the danger of tearing or impingement of the blood vessels and nerves that supply the arms. When pain, point tenderness, discoloration, and athlete's inability to move the extremity exist, immediate first aid treatment should include stabilizing the injured joint (applying a sling), treat the athlete for shock, and immediate medical referral for physician evaluation.

Dislocations: The dislocation of the head of the humerus from its shallow joint is common in sports. Injury to a freely movable, gelenohumeral joint can occur, in which most injuries result in an anterior glenohumeral dislocation. All first-time dislocations should be considered to be fractures by the athletic trainer until X-ray reveals otherwise.

A shoulder dislocation is a dangerous condition that should only be handled by emergency medical personnel. A physician is the only person who should reduce a shoulder dislocation. Damage to vessels and nerves can be a problem with this injury. The anterior glenohumeral dislocation occurs when the arm is abducted and externally rotated, a common mechanism during arm tackling in football. Because of the displacement of the head of the humerus, the injured shoulder will look flat compared with the uninjured side. The athlete may hold the arm slightly abducted. With this injury, supporting ligaments and muscles can be torn, causing hemorrhage. Immobilization of the arm in a comfortable position and basic first aid treatment of protection, rest, ice, compression, elevation and support (PRICES) should be initiated. Shoulder dislocations require immobilization and a complete rehabilitation program to reduce the chance of re-injury. Since most shoulder dislocations occur with the arm in abduction and externally rotated, rehabilitation program should concentrate on adduction and internal rotation movements. Athletes with chronic shoulder dislocations should be checked by the team physician and rehabilitation exercises should strengthen strained muscles or those too weak for the activities of the sport.
 
 

Shoulder Separation: The three non-movable joints in the shoulder girdle are the acromioclavicular (AC), sternoclavicular (SC) and coracoclavicular (CC). When injured, these joints are classified as being separated and or sprained and are classified in one of three categories: first degree (mild), second degree (moderate), or third degree (severe).

First degree sprain: One or more of the supporting ligaments and surrounding tissues are stretched. There is minor discomfort, point tenderness, and little or no swelling. There is no abnormal movement in the joint to indicate lack of stability.

Second degree sprain: A portion of one or more ligaments is torn. There is pain, swelling, point tenderness, and loss of function for several minutes or longer. There is slight abnormal movement in the joint. The athlete may not be able to walk normally and will favor the injured leg.

Third degree sprain: One or more ligaments has been completely torn, resulting in joint instability. There is either extreme pain or little pain (if nerve damage has occurred), loss of function, point tenderness, and rapid swelling. An accompanying fracture is possible.

Acromioclavicular (AC) Sprain: All the ligaments of the shoulder complex can be sprained, but the acromioclavicular sprain is the most common. The frequency of this injury is due to the location of the supporting ligaments on the tip of the shoulder. This injury is often referred to as a separated shoulder. The mechanism of injury is often a blow to the top of the shoulder or a fall on an outstretched arm. Depending on the force, the injury can be classified as first, second, or third degree. The first degree sprain mildly stretches the acromioclavicular ligaments, resulting in pain between the clavicle and acromion process of the scapula. There is no deformity. The second degree sprain has some tearing of the ligaments, resulting in clavicle displacement. The athlete will express pain, discomfort and inability to perform range of motion exercises. Third degree sprains result in extreme pain and obvious displacement of the clavicle. Surgery may be required.

A simple functional test that can be done to confirm an AC sprain is to have the athlete touch the opposite shoulder with the hand of the injured side. If there is an AC sprain, this movement may be painful, and perhaps even impossible to perform, depending on the severity of the injury. Basic first aid treatment for AC sprains includes protection, rest, ice, compression, elevation and support (arm sling) along with referral to a physician for evaluation. Once healing has occurred, the sports medicine team can implement a comprehensive rehabilitation program. Prior to return to physical activity, selection of preventive/supportive techniques and protective devices can be utilized to reduce the occurrence of re-injury.

Muscular Strains: Since the shoulder has many movements, muscular strains to the shoulder girdle are common. Common causes of shoulder muscle strains are lack of strength, repetitive overuse, improper technique and inadequate warm-up. When palpating the area, the student athletic trainer may note soreness or pain primarily in the soft tissue. Manual resistance to every movement the shoulder can make help reveal the injured muscle. As the student athletic trainer resists the athlete's flexion, extension and other movements, one particular range of motion may produce the most pain. The basic treatment should consist of protection, rest, ice, compression, elevation, and support.

Contusions of the Shoulder: Both the muscles and the bones of the shoulder are often bruised in sports. The distal aspect of' the clavicle is especially susceptible to contusion, commonly known as a shoulder pointer. Once an AC sprain has been ruled out, treatment of contusion should include the basic treatment of PRICES along with protective padding utilized prior to return to physical activity.

Brachial Plexus:

As previously reviewed in chapter ten, a cervical or shoulder girdle injury often seen in football is the stretching of one or more of the brachial plexus nerves. This nerve group begins in the neck and innervates the upper extremities. When the brachial plexus becomes stretched or contused, a burning sensation is produced that extends from the point of injury into the arm, often resulting in temporary loss of function and numbness of the arm.

An athlete who has suffered from cervical nerve stretch syndrome must be removed from competition and checked by a physician. Medical clearance by the physician must be obtained before further athletic participation is permitted.

REHABILITATION

Before sending an athlete back to competition, the following rehabilitation guidelines must be met:

The sports medicine team should design the athlete's comprehensive rehabilitation program. A list of suggested rehabilitation exercises are outlined next.

Range of Motion Exercises

Flexion and Extension
Abduction and Adduction
Horizontal Abduction and Adduction
Internal and External Rotation--with arm at the side of the body
Internal and External Rotation--with the arm abducted to 90 degrees
Circumduction
Elevation and Depression
Protraction and Retraction
Shoulder and Upper Arm Strengthening Exercises Incline bench press
Non-gravity pendular movements
Overhead press
Push-ups
Rowing
Shoulder wheel
Towel movement routine
Included in any rehabilitation protocol would be the following: PREVENTIVE/SUPPORTIVE TECHNIQUES

An outline of basic taping and wrapping techniques is listed next. For detailed information, consult this chapter's references.

Wrapping Techniques for Support

Taping Techniques for the Shoulder PROTECTIVE DEVICES

Listed next are various protective devices that are commercially available to use as an adjunct or replacement to taping or wrapping procedures. Prior to use, consultation with an equipment specialist and certified athletic trainer is highly encouraged.

MUSCULOSKELETAL CONDITIONS/DISORDERS

Listed next are musculoskeletal conditions/disorders that affect the shoulder and upper arm. Define and review these conditions using a medical dictionary.

REFERENCES

American Academy of Orthopedic Surgeons (1991) Athletic Training and Sports Medicine (2nd ed.). Park Ridge, IL; American Academy of Orthopedic Surgeons.

Arnheim, D. & Prentice, W. (1997). Principles of Athletic Training (9th ed.). St. Louis: McGraw-Hill.

Anderson M. and Hall S. (1995) Sports Injury Management Baltimore: Williams and Wilkins.

Daniels, Lucille and Worthingham, Catherine. Muscle Testing: Techniques of Manual Examination. Philadelphia: W.B. Saunders, 5th ed., 1986.

Gallaspy, J. & May D. (1996) Signs and Symptoms of Athletic Injuries St. Louis, Mosby

Harrelson G. & Andrews J. (1993) Physical Rehabilitation of the Injured Athlete Philadeplhia: W.B. Saunders

Hoppenfield, S. (1976) Physical Examination of the Spine and Extremities New York: Appleton, Century, and Crofts.

Norkin & White (1985) Measurement of Joint Motion: A Guide to Goniometry Philadelphia: F.A. Davis Co..

Stone R. & Stone J. (1997) Atlas of Skeletal Muscles (2nd ed.) Dubuque: McGraw Hill.

Wright K. & Whitehill W. (1996) The Comprehensive Manual of Taping and Wrapping Techniques Gardner: Cramer Products

Suggested Multimedia Resources

Wright, K, Harrelson, G. Fincher L & Floyd, R. (1996) Sports Medicine Evaluation Series: Shoulder Dubuque: McGraw Hill.

Wright K. & Whitehill W. (1997) Sports Medicine Taping Series: Shoulder and Elbow Dubuque: McGraw Hill.
 
 

The Comprehensive Manual for Taping and Wrapping Techniques

Sports Medicine Evaluation Series: Shoulder


Chapter 11 - Review Questions

Completion:

1. The _______ _______ is the point where the clavicle articulates with the scapula.

2. The clavicle does not articulate with the __________.

3. Palpate the area ____ and ____ the injury first, working ____ the injury site.

4. The _____ glenohumeral dislocation occurs when the arm is _____ and _______ rotated.

5. The four bones that make up the shoulder/upper arm complex are the __________, the ________, and the __________.

6. The __________ end of the clavicle articulates with the sternum. The __________ end articulates with the acromion process.

7. _______ attach the scapula to the clavicle.

8. Resistance to shoulder movements can often reveal an injury to a specific ________.

9. With a shoulder dislocation, you should always suspect a __________.

10. Contusions of the distal end of the clavicle are called __________ __________.

11. The four deep muscles that stabilize the head of the humerus into the glenoid fossa are referred to as the rotator cuff. The four muscles are: ________, __________, ___________, and __________.

Short Answer:

1. Name three components of a rehabilitation protocol:

2. Name four shoulder rehabilitative exercises:

3. Name an internal derangement test.

4. Describe the basic first aid treatment for a fractured clavicle.

5. What is a common mechanism of an acromioclavicular (AC) sprain.

 
PICTURES and DESCRIPTION for Chapter 7

Textbook Source: Wright K. & Whitehill W. (1996) The Comprehensive Manual of Taping and Wrapping Techniques Gardner: Cramer Products

GLENOHUMERAL JOINT WRAP

Purpose: provide support to the glenohumeral joint of the shoulder.

Anatomical Structure: Glenohumeral joint

Anatomical position: The athlete should assume this position: Standing with shoulder abducted, elbow flexed, biceps muscle contracted, and hand on low back.

Supplies needed: 6" extra long elastic wrap, and 2" elastic tape.

Pre-Wrapping Procedure: Instruct the athlete to breathe deeply, expanding the chest. Then, you may begin your wrap.

Wrapping Procedures:

  1. A continuous strip of 6" elastic wrap is applied in a shoulder spica method. This supportive technique should restrict abduction and external rotation of the glenohumeral joint. Begin on the distal aspect of the biceps muscle of the affected arm, move anteriorly, and encircle the arm.
  2. Continue the wrap across the anterior aspect of the chest, under the opposite arm, across the posterior aspect of the torso, and encircle the distal aspect of the upper arm.
  3. Repeat this procedure a second time.
  4. Secure the wrap by using a continuous strip of elastic tape in the same pattern as the wrap. Anchor the wrap with 2" elastic tape following the same pattern as the wrap.
  5.  
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