Sporting Elbow - Clinical Reasoning and Differential Diagnosis

Original Editor - Wanda van Niekerk based on the course by Ian Gatt
Top Contributors - Wanda van Niekerk, Kim Jackson, Jess Bell, Robin Leigh Tacchetti and Robin Tacchetti

Introduction

The elbow is a complex joint and stability is provided by osseous and soft-tissue constraints. The elbow's relative instability makes it vulnerable to injuries, often caused by sports and these injuries often involve several of the structures associated with the joint. Apart from the clinical history, clinical reasoning and the physical examination are essential to make a diagnosis.

Anatomy of the Elbow

The distal humerus meets the proximal radius and ulna bones to form the elbow joint. 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) (i.e. pronation and supination). It is an extremely congruent and stable joint. The stability of the elbow is provided by the osseous anatomy, capsuloligamentous structure and the musculotendinous units that cross the elbow.

Joints

The humerus, radius and ulna articulate to form the three joints that make up the elbow. Table 1 provides an anatomical overview of the elbow. For more detailed information on the specific elbow joints, please read: The Complex Anatomy of the Elbow - Joints

Table 1: Anatomical overview of the elbow

	Humeroulnar Joint	Radiohumeral Joint	Proximal Radioulnar Joint
Active range of motion norms	Flexion 140° Extension 0 - 10°	Flexion 140° Extension 0 - 10°	Pronation 80 -90° Supination 80 -90°
Capsular pattern	Flexion and extension	Flexion and extension	Equal limitations of supination and pronation
Ligaments	Ulnar collateral ligament (UCL -anterior oblique bundle; posterior oblique bundle; intermediate bundle; transverse ligament) Lateral ulnar collateral ligament (LUCL)	Radial collateral ligament (RCL)	Annular ligament Quadrate ligament Oblique cord Interosseous membrane

Ligaments and Capsule

Elbow Joint

The Medial Collateral Ligament Complex (MCLC) / Ulnar Collateral Ligament is the most important stabiliser of the elbow and it provides valgus and posteromedial stability. It comprises an anterior and posterior bundle and a supporting transverse ligament (ligament of Cooper). The anterior band is more taught in extension and relaxes into flexion, whereas the posterior band tightens in flexion and releases in extension. Thus, the anterior band is more vulnerable to valgus stress in elbow extension and the posterior band of the anterior medial collateral ligament (AMCL) is more vulnerable to valgus stress in elbow flexion.

The Lateral Collateral Ligament Complex (LCLC) is the primary stabiliser against varus and external rotation stresses. It is formed by the lateral ulnar collateral ligament, the radial collateral ligament and the annular ligament.

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

For more information, please read: The Complex Anatomy of the Elbow - Ligaments and Capsule

Muscles

Muscle Synergy of the Elbow
Flexion	Primary Flexors: Biceps brachii Brachialis Brachioradialis Secondary Flexors: Pronator teres Extensor carpi radialis longus Flexor carpi radialis (at elbow angles 50 degrees or more)
Extension	Primary Elbow Extensors Triceps Anconeus Secondary Extensors Flexor carpi ulnaris Extensor carpi ulnaris
Pronation	Pronator teres Pronator quadratus
Supination	Mainly biceps Assistance from supinator Lesser degree finger and wrist extensors

Differential Diagnosis

Take into consideration both form (structures) and function in the differential diagnosis of the elbow.

Form

• Cervical radiculopathy (referred pain)
• Systemic conditions (e.g. Rheumatoid Arthritis)
• Anterior elbow:
  • Biceps strain/tear/tendinopathy
  • Myositis ossificans in brachioradialis
  • Osteochondritis dissecans (trochlea)

• Posterior elbow
  • Triceps strain/tears/tendinopathy
  • Olecranon bursitis
  • Osteochondritis dissecans (olecranon)
  • Olecranon spurs/loose bodies

• Radial side of elbow
  • Synovial plica
  • Lateral epicondylalgia (involvement of extensor carpi radialis brevis)
  • Osteochondritis dissecans (radio-capitellum)
  • Posterolateral rotatory instability (PLRI) - radiocarpal ligament combined with lateral ulnar collateral ligament
  • Nerve entrapment: posterior interosseus nerve (radial tunnel syndrome)

• Ulnar side
  • Medial epicondylalgia (Golfer’s Elbow)
  • Nerve entrapment of ulnar nerve
  • Dislocations can cause injury to the ulnar nerve

• Fractures

It is evident that there is a large number of conditions related to form that should be considered with the differential diagnosis of elbow pain. Thus, it can be helpful to distinguish between traumatic and non-traumatic mechanisms.

Table 1: Sporting elbow conditions and the common sports it can occur in

Diagnosis	Sport in which injury commonly occur
Biceps tendon rupture	Strength training; weightlifting
Lateral elbow tendinopathy	Sports associated with repeated gripping and/or wrist extension activities such as tennis, squash, badminton
Flexor/pronator tendinopathy (golfer's elbow)	Golf and in tennis players who uses a lot of topspin on their forehand
Medial collateral ligament sprain	Throwing sports such as baseball, javelin, water polo, handball, cricket
Ulnar nerve entrapment	Throwing sports
Olecranon bursitis	Athletes falling on the posterior aspect of the elbow on hard surfaces in sports such as football (goalkeepers) and basketball
Posterior dislocation	Contact sports or when falling from a height such as pole vaulting

Function

Although the form/structures might be compromised in athletes with elbow injuries, often these individuals still show a high level of function in the injured area. As part of the differential diagnosis, it is key to not only identify the structures involved but also to have a clear picture of function (i.e. what the athlete can do; the pain pattern over time; traumatic vs non-traumatic injury; and urgency vs non-urgency in relation to surgical management).

Kinetic Chain

Factors relevant to function include:

• Kinetic chain
  • Knowledge and understanding of the kinetic chain and how different components can be affected is important. For example, when a boxer throws a punch with his lead arm, the force is coming from the feet driving up into the hip. Approximately 50% of the force will come from the lower legs, 30% from the trunk and 20% from the upper limb.
  • Keep in mind that these percentages may be different in different athletes (i.e. wheelchair-based athletes and swimmers)
  • The key consideration is to acknowledge and understand the whole body contribution in an injury, pathology or dysfunction.

• Strength Testing
  • Isometric testing
    • An examiner applying resistance with their hand in different ranges will provide information on quality
    • Isometric testing with a handheld dynamometer will provide quantitative information in different ranges
  • Isokinetic testing
    • Testing strength through range of motion
  • Strength testing in tennis elbow
    • Dorf et al. investigated the effect of elbow position on grip strength in the evaluation of lateral epicondylitis. They found that there was no difference in grip strength in elbow flexion and extension for the healthy extremity. Grip strength was 29% stronger in elbow flexion than extension for the affected extremity. When comparing the healthy extremity with the affected extremity, the affected extremity was 50% weaker in elbow extension compared to the healthy extremity. In elbow flexion, the affected extremity was 31% weaker than the healthy extremity. This is significant especially with regards to elbow extension providing a mechanical advantage in grip strength of the hand. Using strength testing in people with tennis elbow will provide better objectivity.

• Range of motion
  

  Elbow range of motion measured with smartphone
  • Movements at the elbow to consider and measure:
    • Flexion and extension
    • Pronation and supination
  • Smartphone apps are available to help clinicians measure elbow range of motion.
  • Measuring flexion and extension with an inclinometer app on smartphone
    • Patient rests arm flat on table, so that the humerus is parallel to the horizontal plane. The forearm is in neutral. Inclinometer is set to zero on table. The patient flexes elbow maximally. Smartphone placed parallel to forearm and value can be read.
    • For elbow extension the smartphone is aligned to the forearm in maximal extension.

• End-feel
  • From a manual therapy perspective (especially when range of motion is similar), it is advised to consider the end-feel of the elbow joints. Consider the type of end-feel, as well as the athlete's reaction with this type of provocation.

Special Investigations

• Ultrasound
  • Can assist in the management of stubborn cases of lateral epicondylalgia by characterising the extent of the tendon tearing and identifying the presence of concomitant RCL injury.
• MRI
• Injection (Lignocaine or Marcaine)

Clinical Tests

• Lateral epicondylalgia
  • Middle finger strength test/Maudsley’s test
  • Mill’s test
  • Cozen’s test
  • Chairlift test
  • Polk’s test lateral
  • Grip strength test

• Medial collateral ligament complex/ulnar collateral ligament insufficiency
  • Moving valgus stress test
  • Valgus stress test
  • Milking manoeuvre

Valgus Stress Test video provided by Clinically Relevant

Milking Maneuver Test video provided by Clinically Relevant

• Posterolateral rotatory instability
  • Table-top relocation test
  • Stand-up test/chair push up test
  • Push-up test
  • Lateral pivot shift test

Table Top Relocation Test video provided by Clinically Relevant

Lateral Pivot Shift Test video provided by Clinically Relevant

Chair Sign Test video provided by Clinically Relevant

• Total distal biceps rupture
  • Hook test
  • Passive forearm pronation (PFP) test
  • Supination-pronation test
  • Biceps squeeze test
  • Biceps crease interval (BCI)
  • Bicipital aponeurosis (BA) flex test

• Total distal triceps rupture
  • Triceps squeeze test

• Posteromedial impingement syndrome
  • Arm bar test
  • Valgus overload test/posteromedial impingement test

• Medial epicondylalgia
  • Epicondylitis medialis test/ Golfer’s elbow test
  • Polk’s test medial

Whatever clinical test is being performed, always consider the amount of stress being applied to the structure and the element of safety.

Proximal Radioulnar Joint and Humeroradial Joints in Lateral Epicondylalgia

It is important to consider the proximal radioulnar joint (PRUJ) and the humeroradial joints (HR) in relation to lateral epicondylalgia. Specifically taking into consideration the following:

• Extensor carpi radialis brevis arises from the lateral epicondyle and the annular ligament

• Radial collateral ligament also originates from lateral epicondyle and inserts into the ligament
• The close relationship between ECRB and RCL is seen in:
  • Concomitant injuries
  • Potential instability around this region may provoke lateral epicondylalgia (tennis elbow)

Therefore, having a good understanding of the close relationship between ECRB and RCL, as well as the mobility of the radiohumeral joint will have an impact on lateral epicondylalgia (tennis elbow) management. Furthermore, consider the open- and close-packed positions of the elbow joints to avoid confusion when palpating or mobilising these joints.

PRUJ and HR Joints in LE

Joints	Open Packed	Close Packed
PRUJ	Elbow flexion (70°) Supination (5°)	Elbow extension Full supination
HR	Elbow extension Full supination	Elbow flexion (70°) Supination (5°)

Medial Epicondylalgia and Pronator Teres

• Hypertrophy of pronator teres may lead to symptoms around the medial epicondyle of the elbow.
• Pronator teres syndrome – i.e. the median nerve is trapped between the two heads of pronator – will mainly produce symptoms distally rather than locally.

Conclusion

General guidelines to consider:

• Diagnosis
  • Consider traumatic vs non-traumatic injuries
  • Structures (form) involved

• Prognosis = function
  • What can or can’t the athlete do?
  • Strength
  • Range of motion
  • End feel

• With non-traumatic injuries consider contributions from the shoulder and forearm, as well as the hand and wrist.

• For lateral epicondylalgia and medial epicondylalgia, consider the surrounding structures that could also be involved

• The elbow can be tricky – if unsure get a second opinion!