Orthopaedic Nurses Certification Board (ONCB) Metabolic/Inflammatory/Tumors Practice Exam

Which condition is characterized by severe muscle weakness and difficulty in climbing stairs?

1. Polymyalgia rheumatica

2. Rheumatoid arthritis

3. Polymyositis

4. Giant cell arteritis

The correct answer is: Polymyositis

Polymyositis is characterized by progressive muscle weakness and inflammation, particularly affecting skeletal muscles. One of the hallmark symptoms of this condition is difficulty in performing tasks that require proximal muscle strength, such as climbing stairs or lifting objects. This arises due to the targeted atrophy and inflammation of the muscle fibers, leading to significant weakness. In contrast, conditions like polymyalgia rheumatica primarily involve muscle pain and stiffness rather than weakness, and rheumatoid arthritis, while it can involve joint pain and swelling, does not specifically lead to muscle weakness as a primary symptom. Giant cell arteritis is a vessel-targeted inflammation that can lead to headaches and jaw claudication, primarily affecting older adults, but again does not involve specific muscle weakness. Therefore, the distinct presentation of proximal muscle weakness in polymyositis makes it the correct choice for this question.