INSPECTION

Considerable information can be ascertained from careful visual inspection of the elbow joint. Because much of the joint is subcutaneous, any appreciable alteration in the skeletal anatomy is usually obvious. Gross soft tissue swelling or muscle atrophy is also easily observed.

AXIAL ALIGNMENT

Axial malalignment of the elbow, when compared with the opposite side, suggests prior trauma or a skeletal growth disturbance. To determine the carrying angle, the forearm and hand should be supinated and the elbow extended; the angle formed by the humerus and forearm is then determined (Fig. 4-1A). Although there is considerable variation with race, age, sex, and body weight, an average of 10 degrees for men and 13 degrees for women has been calculated as the mean carrying angle from several reports.^3,4,13,14

FIGURE 4-1 A, The carrying angle is a clinical measurement of the angle formed by the forearm and the humerus with the elbow extended. B and C, The normal 10- to 15-degree carrying angle can be altered by injury about the elbow, causing a varus carrying angle, or so-called gunstock deformity.

Angular deformities, such as cubitus varus or valgus, are also easily identifiable (see Fig. 4-1B and C). The elbow moves from a valgus to varus alignment as with flexion. In a post-traumatic condition, however, abnormalities in the carrying angle cannot be accurately assessed in the presence of a significant flexion contracture (see Chapter 3). Rotational deformities following supracondylar or other fractures of the humeral shaft may be difficult to perceive.

LATERAL ASPECT

Fullness about the infracondylar recess just inferior to the lateral condyle of the humerus, the “soft spot,” suggests either an increase in synovial fluid, synovial tissue proliferation, or radial head pathology, such as fracture, subluxation, or dislocation (Fig. 4-2). Subtle evidence of effusion can be determined by observing fullness in this area.

FIGURE 4-2 A normal depression in the contour of the skin in the intracondylar recess (arrowhead) (A) becomes obliterated in the presence of synovitis or effusion (B).

Thin, taut, adherent skin over the lateral epicondyle may be indicative of excessive cortisone injections in this area for refractory lateral epicondylitis (see Chapter 44). A prominence involving the lateral triangle often indicates a posteriorly dislocated radial head (Fig. 4-3; see Fig. 4-22A and B).

FIGURE 4-3 Developmental posterior dislocation of the radial head (A) is associated with obvious prominence (B). Typically, this problem is associated with only minimal limitation of function.

FIGURE 4-22 A, The patient has done a push-up with hands in neutral and his arms wider than shoulder (valgus) and is at a terminal extension (axial load) of his unaffected elbow. He has apprehension in his affected left elbow (axial load + valgus). B, A close-up of the posterolateral dislocation.

POSTERIOR ASPECT

A prominent olecranon suggests a posterior subluxation or migration of the forearm on the ulnohumeral articulation. Occasionally, marked distortion is associated with surprisingly satisfactory function (Fig. 4-4). Rupture of the triceps tendon at its insertion should be suspected if this finding is accompanied by loss of active extension. Loss of terminal passive extension of the elbow is a sensitive but nonspecific indicator of intra-articular pathology. Loss of active motion with full passive extension suggests either mechanical (triceps avulsion) or neurologic conditions.

FIGURE 4-4 Gross deformity of the elbow from a malunion of a condylar fracture. The excellent function is typical of condylar but not T-Y type malunions.

The prominent subcutaneous olecranon bursa is readily observed posteriorly when it is inflamed or distended (Fig. 4-5). Rheumatoid nodules frequently are found on the subcutaneous border of the ulna (see Chapter 74).

FIGURE 4-5 An inflamed or enlarged olecranon bursa is one of the more dramatic diagnoses made by observation in the region of the elbow.

(From Polley, H. G., and Hunder, G. G.: Rheumatologic Interviewing and Physical Examination of the Joints, 2nd ed. Philadelphia, W.B. Saunders Co., 1978.)

MEDIAL ASPECT

On occasion the ulnar nerve may be observed to displace anteriorly during flexion with recurrent subluxation of the ulnar nerve.⁸ Otherwise, few landmarks are observable from the medial aspect of the joint. The prominent medial epicondyle is evident unless the patient is obese.

ASSOCIATED JOINTS AND NEURAL FUNCTION

No examination of the elbow is complete without a review of the cervical spine and all other components of the upper extremity. If the elbow pain has a radicular pattern, it is important to review the patient’s cervical spine alignment and range of motion and perform neurologic testing of the entire upper extremity. The main nerve roots involved with elbow function are C5-7 (Fig. 4-6). There is considerable overlap in the sensory dermatomes of the upper extremity. The general distribution of sensory levels includes C5, the lateral arm; C6, the lateral forearm; C7, the middle finger; and C8 and T1, the medial forearm and arm dermatomes, respectively.

FIGURE 4-6 The biceps, brachioradialis, and triceps reflexes allow evaluation of the C5, C6, and C7 nerve roots, respectively.

Biceps function from innervation of C5-C6 is a flexor of the elbow and forearm supinator. The reflex primarily tests C5 and some C6 competency. The C6 muscle group of most interest is the mobile wad of three, consisting of the extensor carpi radialis longus and brevis and the brachioradialis muscles. These also are known as the radial wrist extensors and should be assessed for strength and reflex integrity. The reflex is primarily a C6 function, with some C5 component. The primary elbow muscle innervated by C7 is the triceps, which should always be assessed for strength and reflex. Wrist flexion and finger extension also are primarily supplied by C7, with some C8 innervation (see Fig. 4-6).

Elbow pain may be referred from the shoulder; therefore, a visual inspection of the shoulder for muscle wasting and appearance should be made, followed by an appropriate functional assessment. Specific attention should be directed toward motion and the spectrum of impingement tendinitis or rotator cuff pathology which often is manifested by pain in the brachium.

For normal forearm rotation, there must be a normal anatomic relationship between the proximal and distal radioulnar joint. Inflammatory changes involving either the elbow or the wrist or both will cause a loss of forearm rotation. Disruption of the normal relationship of the distal radioulnar joint will cause dorsal prominence of the distal ulna exaggerated by pronation and is lessened by supination. Because pronation is the common resting position of the hand, dorsal subluxation of the ulna at the wrist is often identifiable by inspection.