Sensory information to the area of skin over index finger (dermatome) is subserved by afferent fibers from which dorsal root?

Correct Answer: C

Rationale: The correct answer is C7 because the index finger is innervated by the C7 dermatome. Each spinal nerve innervates a specific area of skin called a dermatome. In this case, the C7 spinal nerve is responsible for providing sensory information to the skin over the index finger. Choices A (C5), B (C6), and D (C8) are incorrect as they do not correspond to the dermatome responsible for innervating the index finger. Therefore, the correct answer is C7 based on the specific dermatomal distribution of sensory fibers.

Correct Answer: A

Rationale: The correct answer is A: Scaphoid. A fall or blow on a hyperextended wrist can disrupt blood flow to the scaphoid bone, leading to osteonecrosis. The scaphoid is vulnerable due to its location and blood supply. Lunate (B), Triquetrum (C), and Pisiform (D) are less likely to be affected in this scenario due to their different anatomical locations and blood supplies.

Correct Answer: A

Rationale: The correct answer is A: Axial skeleton. Skeletal metastases commonly occur in the axial skeleton due to its rich blood supply and high bone turnover rate. This makes it a favorable site for cancer cells to metastasize. Metastases in the femur, humerus, and radius are less common compared to the axial skeleton. The long bones like femur, humerus, and radius are more prone to primary bone tumors rather than metastases. Therefore, the correct answer is A as it aligns with the typical pattern of skeletal metastases.

Correct Answer: D

Rationale: The correct answer is D: Improve efficiency. Cardiac rehabilitation can benefit a patient with angina pectoris by improving the efficiency of the heart muscle, leading to better circulation and reduced workload on the heart. This helps in managing angina symptoms and improving overall cardiovascular health. A: Increasing myocardial oxygen consumption would worsen angina symptoms by putting more strain on the heart. B: Decreasing the maximum heart rate could limit the patient's ability to exercise and improve cardiovascular health. C: Changing the angina threshold does not directly address the underlying issue of heart efficiency and may not provide long-term benefits.

Correct Answer: B

Rationale: The correct answer is B: High frequency, low intensity. This type of TENS stimulator is most effective because high frequency helps to block pain signals from reaching the brain, while low intensity ensures safety and prevents muscle contractions. High frequency stimulates nerve fibers that inhibit pain transmission, providing relief without causing discomfort. A: High frequency, high intensity can be too harsh and may lead to muscle contractions, causing discomfort. C: Low frequency, high intensity may not effectively block pain signals and can cause muscle contractions or discomfort. D: Low frequency, low intensity may not provide sufficient pain relief as it might not effectively block pain signals.