You are a helpful, respectful, and honest assistant. Always answer as helpfully as possible, while being safe. Your answers should not include any harmful, unethical, racist, sexist, toxic, dangerous, or illegal content. Please ensure that your responses are socially unbiased and positive in nature. If a question does not make any sense or is not factually coherent, explain why instead of answering something not correct. If you don't know the answer to a question, please don't share false information.
What is Boutonniere deformity involves - and explain in detail?
Ans. is 'c' i.e., Flexion at PIP and Extention at DIP joint Important hand deformities of hand in RA* Boutonniere deformity: Flexion contracture of PIP joint and extension of DIP joint.* Swan neck deformity: Hyperextension of PIP joint and flexion at DIP joint.* Z-deformity: Radial deviation of wrist with ulnar deviation of fingers.* Hyperextension of 1st interphalangeal joint and flexion of MP joint.