The elbow joint is a synovial hinge joint whose primary function is to aid in the orientation of the hand in space for crucial functions like eating and drinking. The joint’s articular cartilage is susceptible to damage, which left untreated will result in arthritis with its associated pain and functional disability. Osteoarthritis of the joint is the most common form of arthritis that results in elbow joint pain and functional disability, with rheumatoid arthritis, posttraumatic arthritis, and crystal arthropathy also causing arthritis of the elbow joint. Less common causes of arthritis-induced elbow joint pain include the collagen vascular diseases, infection, villonodular synovitis, and Lyme disease. Acute infectious arthritis of the elbow joint is best treated with early diagnosis, with culture and sensitivity of the synovial fluid and prompt initiation of antibiotic therapy. The collagen vascular diseases generally manifest as a polyarthropathy rather than a monoarthropathy limited to the elbow joint, although elbow pain secondary to the collagen vascular diseases responds exceedingly well to ultrasoundguided intra-articular injection of the elbow joint.

Patients with elbow joint pain secondary to arthritis, synovitis, and gout and collagen vascular disease-related joint pain complain of pain that is localized to the elbow and forearm. Activity makes the pain worse, with rest and heat providing some relief. The pain is constant and characterized as aching. Sleep disturbance is common with awakening when patients roll over onto the affected elbow. Some patients complain of a grating, catching, or popping sensation with range of motion of the joint, and crepitus may be appreciated on physical examination.

Functional disability often accompanies the pain and many pathologic conditions of the elbow joint. Patients will often notice increasing difficulty in performing their activities of daily living and tasks that require flexing or extending the elbow such as lifting heavy objects and holding a coffee cup. If the pathologic process responsible for the elbow pain is not adequately treated, the patient’s functional disability may worsen, and muscle wasting and ultimately a frozen elbow may occur.

Plain radiographs are indicated in all patients who present with elbow pain (Fig. 51.1). Based on the patient’s clinical presentation, additional testing may be indicated, including complete blood cell count, sedimentation rate, and antinuclear antibody testing. MRI or ultrasound of the elbow is indicated if tendinopathy, crystal arthropathy, fracture, joint mice, synovitis, bursitis, or ligamentous injury is suspected (Fig. 51.2).

The elbow joint is a synovial hinge-type joint that allows the distal humerus to articulate with the proximal radius and ulna (Fig. 51.3). The joint allows flexion and extension as well as supination and pronation. The joint’s articular surface is covered with hyaline cartilage, which is susceptible to arthritis and degeneration. This membrane gives rise to synovial tendon sheaths and bursae that are subject to inflammation. The entire elbow joint is surrounded by ligaments, which coupled with the extremely deep bony articular socket makes the joint stable throughout its range of motion (Figs. 51.4 and 51.5). The joint capsule is lined with a synovial membrane, which attaches to the articular cartilage. This membrane gives rise to synovial tendon sheaths and bursae that are subject to inflammation and swelling, especially in the anterior and posterior aspects of the joint where the joint capsule is less dense. The olecranon bursa lies in the posterior aspect of the joint, while the cubital bursa, which is also known as the bicipitoradial bursa, lies anteriorly (Figs. 51.6 and 51.7). Both are subject to the development of bursitis with misuse or overuse of the elbow joint. The primary innervation of the elbow joint comes from the musculocutaneous and radial nerves with some lesser contribution from the median and ulnar nerves. As the ulnar nerve passes inferiorly down the upper arm, it courses medially at the mid humerus to pass between the olecranon process and medial epicondyle of the humerus (Fig. 51.8). The nerve is extremely susceptible to entrapment and trauma at this point. Anteriorly, the median nerve lies just medial to the brachial artery and is occasionally susceptible to damage during puncture of the brachial artery when drawing arterial blood gasses.