1. Chapter 15
The Elbow Complex

2. Overview
The elbow complex is an inherently strong and stable compound joint, which is enclosed within the capsule of the cubital articulation. The stability of the elbow complex, gives it very little in the way of compensatory adjustments, making it prone to overuse injuries
The primary function of the elbow complex is to work together with the shoulder to position the hand for functional activities

3. Anatomy
The elbow complex is comprised of three distinct articulations:
The humeroulnar joint
The humeroradial joint
The proximal radioulnar joint

4. Humeroulnar Joint
A uniaxial hinge joint formed between the trochlear notch of the proximal ulna and the spool-shaped trochlea of the humerus
The angulation of this joint forms the “carrying angle”
The carrying angle is approximately 11-14° in males and 13-16° in females

5. Humeroradial Joint
A uniaxial hinge joint formed between the spherical capitellum of the humerus, and the concave head of the radius
The design of this joint allows the elbow to flex and extend, and for the radius to rotate

6. Proximal Radioulnar Joint
The proximal (superior) radioulnar joint is a uniaxial pivot joint formed between the periphery of the convex radial head, and the fibrous osseous ring formed by the concave radial notch of the ulna
The annular ligament forms 80% of the articular surface of the proximal radioulnar joint

7. Joint Capsule
The joint capsule of the elbow complex is thin but strong
The capsule of the joint does not respond well to injury or prolonged immobilization, and often forms thick scar tissue, which may result in flexion contractures of the elbow

8. Medial (Ulnar) Collateral Ligament
The fan-shaped MCL is functionally the most important ligament in the elbow for providing stability against valgus stress, particularly in the range of ° of flexion and extension
There are three distinct components of the MCL:
Anterior bundle
Transverse bundle
Posterior bundle

9. Medial (Ulnar) Collateral Ligament
Anterior bundle
Anterior band
The strongest and stiffest of the elbow collateral ligaments
Primarily stabilizes the elbow against valgus stress in the ranges of ° of flexion, and becomes a secondary restraint with further flexion

10. Medial (Ulnar) Collateral Ligament
Anterior bundle
The posterior band
Taut beyond 55° of elbow flexion
A secondary restraint to valgus stress at lesser degrees of flexion
An equal co-restraint with the anterior band at terminal elbow flexion
A primary restraint to passive elbow extension

11. Medial (Ulnar) Collateral Ligament
The transverse bundle
Also known as Cooper’s ligament
Fibers both originate and insert on the ulna and therefore have little role in elbow stability

12. Medial (Ulnar) Collateral Ligament
Posterior bundle
Appears to be a thickening of the posterior elbow capsule
Provides only secondary restraint to valgus stress at flexion beyond 90°.

13. Lateral (Radial) Collateral Ligament
Consists of:
The annular ligament
The fan-like radial collateral ligament
The accessory collateral ligament
The lateral ulnar collateral ligament
The LCL functions to maintain the ulnohumeral and radiohumeral joints in a reduced position when the elbow is loaded in supination

14. Annular Ligament
The annular ligament functions to maintain the relationship between the head of the radius and the humerus and ulna

15. Bursae
The olecranon bursa is the main bursa of the elbow complex and lies posteriorly between the skin and the olecranon process
Under normal conditions the bursa does not communicate with the elbow joint, although its superficial location puts it at high risk for injury from direct trauma to the elbow

16. Elbow Flexors
The prime movers of elbow flexion are the biceps, brachialis, and brachioradialis
The pronator teres, flexor carpi radialis (FCR), and flexor carpi ulnaris (FCU), and the extensor carpi radialis longus (ECRL) muscles are considered as weak flexors of the elbow

17. Elbow Extensors
There are two muscles that extend the elbow: the triceps and the anconeus

18. Forearm Pronators Pronator teres Pronator quadratus
Flexor carpi radialis

19. Forearm Supinators
Biceps
Supinator

20. Cubital tunnel A fibro-osseous canal that contains the ulnar nerve
The floor of the tunnel is formed by the MCL
The roof is formed by an aponeurosis, the arcuate ligament
The medial head of the triceps constitutes the posterior border of the tunnel
The anterior and lateral borders are formed by the medial epicondyle and olecranon, respectively
The volume of the cubital tunnel is greatest with the elbow held in extension

21. Cubital Fossa
The cubital fossa represents the triangular space, or depression, which is located over the anterior surface of the elbow joint, and which serves as an ‘entrance’ to the forearm, or antebrachium

22. Cubital Fossa The contents of the fossa include:
The tendon of the biceps brachii lies as the central structure in the fossa
The median nerve
The brachial artery
The radial nerve
The median cubital or intermediate cubital cutaneous vein

23. Nerves
Ulnar
Radial
Median

24. The Arcade of Fröhse
The arcade of Fröhse is an inverted arched structure that lies within 1 cm distal of the fibrous edge of the ECRB and approximately 2 to 4 cm distal to the radiohumeral joint
It represents the proximal border of the superficial head of the supinator, through which the radial nerve passes

25. The Radial Tunnel/Supinator Canal
The radial tunnel lies on the anterior aspect of the radius, and is approximately three to four finger breadths long, beginning just proximal to the radiohumeral joint, and ending at the site where the nerve passes deep to the superficial part of the supinator muscle

26. Biomechanics
Biomechanically, the elbow predominantly functions as an important link in the upper extremity kinetic chain, allowing the generation and transfer of forces which occur in the upper extremity.

27. Humeroulnar Joint
The resting, or open pack, position for the humeroulnar joint is 70° of flexion with 10° of forearm supination
The closed pack position is full extension and maximum forearm supination
The capsular pattern is much more limitation in flexion than extension

28. Humeroradial Joint
The resting, or open pack, position of the humeroradial joint is extension and forearm supination
The closed pack position is approximately 90° of elbow flexion and 5° of supination
There is no true capsular pattern at this joint, although clinically an equal limitation of pronation and supination is observed

29. Proximal Radioulnar Joint
The resting, or open pack, position for the proximal radioulnar joint is 70° flexion and 35° of forearm supination
The closed pack position is 5° of forearm supination
The capsular pattern is minimal to loss of motion, with pain at the end ranges of pronation and supination

30. Force Couples of the Elbow
The triceps/biceps during arm extension and flexion
Flexor carpi radialis (FCR), flexor carpi ulnaris (FCU), flexor digitorum communis (FDC)/Extensor carpi radialis longus (ECRL), extensor carpi radialis brevis (ECRB), extensor communis (EC) during wrist flexion and extension

31. Force Couples of the Elbow
Pronator teres, pronator quadratus/supinator during forearm pronation and supination
Triceps/biceps, brachioradialis; pronator teres/supinator; FCR, FCU/ECRB, ECRL during activities requiring elbow stabilization

32. Examination
History
During the history, the clinician must determine the chief complaint and whether there is a specific mechanism of injury
Where is the pain?
Was there any antecedent trauma or overuse?
Is there any paresthesia?
What makes the symptoms better/worse

33. Examination Systems Review
The clinician should be able to determine the suitability of the patient for physical therapy
If the clinician is concerned with any signs or symptoms of a visceral, vascular, neurogenic, psychogenic, spondylogenic or systemic disorder that is out of the scope of physical therapy, the patient should be referred to an appropriate healthcare provider

34. Examination Observation
The affected elbow should be inspected for scars, deformities, and swelling
The clinician should observe the ‘carrying angle’ of the elbow and compare it to the other side

35. Examination Palpation
Because they are superficial, most of the elbow structures are easily palpable, making it easier for the clinician to pinpoint the specific area of pain

36. Examination Active range of motion with passive overpressure
It is important to determine how much range of motion (ROM) is necessary for the patient to perform his or her job and recreational activities
The patient is asked to perform active flexion, extension of the elbow, pronation and supination of the forearm, and wrist flexion and extension. The ranges are recorded

37. Examination Resistive testing
In addition to all of the shoulder muscles that insert at or near the elbow (biceps, brachialis, triceps), the clinician must also test the muscles responsible for elbow flexion, and extension, forearm supination, pronation, and wrist flexion and extension

38. Examination Functional assessment
A number of tests have been designed to assess elbow function

39. Examination Passive articular motion testing The ulnohumeral joint
The radiohumeral joint
The proximal radioulnar joint
The distal radioulnar joint

40. Examination Stress tests
Medial (ulnar) collateral ligament (valgus test)
Lateral (radial) collateral ligament (varus test)

41. Examination Special tests Tennis elbow tests Golfer’s Elbow test
Cozen’s test
Mill’s test
Golfer’s Elbow test
Cubital tunnel syndrome tests
Elbow flexion
Pressure provocative test
Tinel’s Sign (at the elbow)

42. Intervention Strategies
Acute Phase
Protection of the injury site
Restoration of pain-free range of motion in the entire kinetic chain
Improve patient comfort by decreasing pain and inflammation
Retard muscle atrophy
Minimize detrimental effects of immobilization and activity restriction
Maintain general fitness
Patient to be independent with home exercise program

43. Intervention Strategies
Functional Phase
Attain full range of pain free motion
Restore normal joint kinematics
Improve muscle strength to within normal limits
Improve neuromuscular control
Restore normal muscle force couples