Examination of the Elbow Region
Examination of the Elbow Region
LEARNING OUTCOMES
After studying this chapter, you should be able to:
. Outline the key anatomical structures and biomechanical functions of the elbow joint complex.
. Discuss common pathological presentations for this region.
. Identify how clinical reasoning guides history taking in the subjective examination of people with elbow complex pain and/or dysfunction, informed by the location, behaviour and nature of symptoms, and the value of screening questions. . Discuss the multifactorial nature of elbow pain and the role psychosocial factors may play in how people with elbow dysfunction may present.
. Identify how subjective data will guide the physical examination of the elbow complex.
. Using clinical reasoning, justify selection of tests and interpretation of findings related to common pathological presentations of the elbow complex.
. List the key constituents of a comprehensive physical examination of the elbow complex with considerations of the sensitivity and specificity of key physical tests for the elbow joint region.
. Explain how physical examination findings contribute to reasoning of common pathologies of the elbow joint.
INTRODUCTION TO THE ELBOW REGION
INTRODUCTION TO THE ELBOW REGION
The elbow complex is composed of three bones, the humerus, ulna and radius, which together form three separate articulations: the humeroulnar joint, the humeroradial joint and the superior radioulnar joint. The joint capsule is continuous for all three joints and is reinforced by the collateral ligaments, which contribute to elbow stability. The humeroulnar joint provides most structural stability due to the tight fit between the trochlea and the trochlear notch. It is primarily involved in flexion and extension. The humeroradial joint allows flexion and extension movements as well as pronation and supination. The elbow is not considered a weight-bearing joint; however, activities such as pushing and press-ups do subject the humeroradial joint to compression forces and should be considered. The superior and inferior radioulnar joints are considered as one joint; however, in this text the inferior radioulnar joint is discussed in Chapter twelve. They are primarily involved in supination and pronation movements and therefore are essential in fine-tuning wrist and hand spatial positioning.
The muscles associated primarily with the elbow include three flexors (brachialis, biceps brachii and brachioradialis) and two extensors (triceps and anconeus). The role these muscles have in elbow movement depends on many factors, including functional elbow and forearm positions, type of muscle contraction and associated load. In addition, the humerus provides a stable base of attachment for many of the wrist and hand muscles via the common flexor/pronator and extensor tendon origins, which are the medial and lateral dynamic stabilizers of the elbow joint, respectively. These tendon origins are susceptible to overload and degenerative changes.
Anatomically the elbow forms part of the kinetic chain for the upper limb, sitting between the mobile shoulder, wrist and hand joints. The elbow's primary role is to optimize hand function by enabling an individual to place the hand in a variety of positions to perform functional activities. Normal elbow physiological ranges for flexion and extension range between negative five degrees hypertension and one hundred forty-five degrees flexion, although most functional activities usually occur between thirty and one hundred forty degrees of flexion, meaning one does not need to have full elbow range to be fully functional.
The superior radioulnar joint has on average seventy-five degrees of forearm pronation and eighty-five degrees of supination. These physiological ranges enable a wide variety of activities. For example, elbow flexion and supination are used to bring the hand to the face and body in activities of daily living, such as eating, dressing and carrying. Similarly, elbow extension and pronation together enable the hand to be used in reaching, pushing, throwing and weight bearing, for example through a walking stick. The elbow joints therefore allow transmission of forces to or from the hand such as torque as a result of twisting for example using a screwdriver or compression for example pushing a heavy door. Any gross loss of flexion or extension range may significantly limit the level of functional independence for an individual, with a fifty percent loss of range resulting in an eighty percent functional loss. In contrast, compensations at the elbow may arise when there are dysfunctions at the wrist or shoulder, reminding us of the importance of screening these regions too.
Elbow injuries affect people of all ages and activity levels and result in significant pain and disability. Elbow pain potentially may be described as arthrogenic, myogenic, neurogenic or a combination of these, depending on the structures involved. Sports involving overhead throwing, repeated use of power grips for example golf and tennis and compression for example divers, gymnasts and weightlifters are particularly associated with acute and chronic elbow pathologies.
Particular symptoms may be indicative of certain conditions. For example, numbness and tingling in the little finger while talking on the phone may suggest ulnar neuropathy, twinges of pain on turning a key may be related to the superior radioulnar joint and an inability to extend the elbow fully may suggest synovitis or osteoarthritis. See Table eleven point one for possible causes of pain and/or limitation of movement. Limitation of cervical or glenohumeral joint range, along with glenohumeral joint weakness, has also been linked to elbow joint pathology.