A 37-year-old woman comes to the office due to left elbow discomfort and swelling for the past several days. The patient recalls no major trauma but has been participating in a high-intensity workout program recently. Physical examination findings are shown in the exhibit.

The patient is able to fully extend the elbow without increased pain. Pathology involving which of the following structures is the most likely cause of this patient's current condition?

Question

A 37-year-old woman comes to the office due to left elbow discomfort and swelling for the past several days.  The patient recalls no major trauma but has been participating in a high-intensity workout program recently.  Physical examination findings are shown in the exhibit.
 
The patient is able to fully extend the elbow without increased pain.  Pathology involving which of the following structures is the most likely cause of this patient's current condition?

Quizplus · Accepted Answer

This patient has olecranon bursitis with localized swelling over the posterior elbow. The olecranon bursa is a fluid-filled synovial sac between the olecranon process and the skin that alleviates friction at the bony prominence. Repetitive pressure or overuse (eg, upper extremity exercise) can injure the bursa, leading to synovial fluid accumulation within it. Bursitis due to overuse is noninflammatory; associated discomfort is typically mild. However, inflammatory bursitis (eg, gout, rheumatoid arthritis, infection) can present with significant erythema and pain. Because the bursa is not an intraarticular structure, bursitis typically does not interfere with joint range of motion (ie, there is normal, pain-free range of motion) unless it is significantly enlarged or inflamed. In contrast, intraarticular pathologies (eg, septic arthritis, intraarticular fracture) that involve the capsule, synovium, or bone impair range of motion due to joint effusion and pain; diffuse joint swelling (not localized bursal swelling) is typically present (Choices B and C). (Choice A) The annular ligament encircles the radial head and holds it and the ulna together. In children, ligamental laxity can predispose to radial head subluxation (ie, nursemaid elbow) when axial traction is applied to the arm. Affected patients have mild tenderness in the anterolateral elbow (radial head) that is worsened by forearm supination. Swelling is not seen. (Choice E) The triceps muscle originates from the infraglenoid tubercle of the scapula and posterior humerus and inserts onto the posterior olecranon; it extends the elbow. Triceps tendon injury leads to pain at the posterior olecranon with elbow extension, and significant swelling would be atypical. Educational objective: Olecranon bursitis presents with localized swelling at the olecranon process. Pain and erythema are typically minimal or absent unless significant inflammation is present. A bursa is not an intraarticular structure; therefore, range of motion of the associated joint is typically preserved and pain-free. __________ References: Common superficial bursitis. (http://www.ncbi.nlm.nih.gov/pubmed/28290630)

A 37-Year-Old Woman Comes to the Office Due to Left