Physiotherapy Management of the Elbow

Contributors-

Original Editor - Mandy Roscher Top Contributors - Mandy Roscher, Kim Jackson, Wanda van Niekerk, Tarina van der Stockt, Rucha Gadgil and Jess Bell

The Complex Anatomy of the Elbow

The elbow joint is where the distal humerus meets the proximal radius and ulna bones. It is known as a trochleogingylomoid joint as it can flex and extend as a hinge (ginglymoid) joint as well as pivot around an axis (trochoid motion) known as pronation and supination. It is an extremely congruent joint and is inherently stable with injuries at the elbow resulting in an inheritably unstable joint.

Joints

The humerus, radius and ulna articulate to form 3 joints that make up the elbow.

Ulnohumeral Joint

The ulnohumeral hinge joint is responsible for flexion and extension. The spool-shaped trochlea of the humerus articulates with the greater sigmoid arch of the proximal ulna.

Radiocapitellar Joint

The radiocapitellar joint is where the radius and humerus articulate. It is partly responsible for pronation and supination. The capitellum of the lateral distal humerus is a spherical structure onto which the concave surface of the proximal radial head articulates.

Proximal Radioulnar Joint

The proximal radioulnar joint is a trochoid joint responsible for pronation or supination of the forearm. The peripheral edge of the radial head articulates with the radial notch of the ulna.

Carrying Angle

The carrying angle is measured when the elbow is in full extension and supination. It is an angle measured along the long axis of the humerus and ulna. In men, it is approximately 11-14° and women 13-16°. Is it appropriately named as it allows our arms to clear our hips as we walk and allows objects to be carried.

Movements at the Elbow

Flexion and Extension

Flexion and Extension occurs at the ulnohumeral joint. Normal range of movement is from 0-140° but only 30°-130° is required for most ADLs

Pronation and Supination

The radiocapitellar joint and proximal radioulnar joint are responsible for pronation and supination. Normal ROM is considered approximately 180° (80-90 pronation and 90 supination). 100° of movement (50° pronation and 50° supination) is considered adequate for most ADLs. If pronation ROM is lost this can be compensated by using shoulder abduction. But, there is no compensatory action for supination and as such a loss of supination ROM can pose a greater disability than a loss of pronation ROM.

Ligaments and Capsule

There are 2 main ligament complexes at the elbow namely the Medial and Lateral Collateral.

Medial Collateral Ligament Complex (MCLC)

The MCLC is comprised of the anterior bundle, posterior bundle and transverse ligament (the ligament of Cooper). The anterior bundle is considered to be the most important stabiliser of the elbow and provides valgus and posteromedial stability. The anterior bundle is further divided into the anterior and posterior bands. The anterior band is more taught in extension and relaxes into flexion and the posterior band is taught in flexion and releases in extension. This makes the anterior band more vulnerable to valgus stress when the elbow is extended and the posterior band of the AMCL more vulnerable to valgus stress when the elbow is flexed.

Lateral Collateral Ligament Complex (LCLC)

The LCLC is the primary stabiliser against varus and external rotation stresses. The lateral ulnar collateral ligament, the radial collateral ligament and the annular ligament form the LCLC. The lateral ulnar collateral ligament is important in maintaining posterolateral rotatory stability as well as stabilising against varus stresses. The radial collateral ligament also contributes to posterolateral rotational stability. The Annular ligament surrounds the radial head but does not attach to it. It is am important stabiliser of the proximal radioulnar and radiocapitellar joint.

Joint Capsule

The joint capsule of the elbow surrounds all 3 joints. There are thickening medially and laterally of the joint capsule that blend with the MCLC and LCLC respectively and contributes to stability of the elbow.

Musculature

There are 4 main muscle groups at the elbow. The anterior bicep group, the posterior tricep group, the lateral extensor-supinator group and the medial flexor-pronator group

Each muscle group applies a compressive load to the elbow joint when they contract.

• Primary Elbow Flexors
  • Brachialis
  • Biceps brachii
  • Brachioradialis
• Secondary Elbow Flexors
  • Pronator teres
  • Extensor carpi radialis longus
  • Flexor carpi radialis (at elbow angles 50 degrees or more)
• Primary Elbow Extensors
  • Triceps
  • Anconeus
• Secondary extensors
  • Flexor Carpi ulnaris
  • Extensor carpiulnaris
• Pronation
  • Pronator teres
  • Pronator quadratus
• Supination
  • Mainly Biceps
  • Assistance from supinator
  • Lesser degree finger and wrist extensors