Compression of which nerve is commonly misdiagnosed as lateral epicondylitis?

Correct Answer: A

Rationale: The correct answer is A: Posterior interosseous nerve. Compression of this nerve can mimic lateral epicondylitis due to similar symptoms like wrist and finger extension weakness. The other choices are incorrect because: B: Anterior interosseous nerve compression presents with different symptoms, C: Median nerve compression typically causes different symptoms like carpal tunnel syndrome, and D: C8/T1 nerve roots are associated with different conditions like thoracic outlet syndrome.

Correct Answer: C

Rationale: The correct answer is C: The spinoglenoid notch of the scapula. Isolated infraspinatus weakness and atrophy is indicative of a lesion at the spinoglenoid notch, which is where the suprascapular nerve passes to innervate the infraspinatus muscle. The suprascapular notch (A) is more related to the supraspinatus muscle. C5 nerve root (B) involvement would typically present with a wider range of muscle weakness. The upper trunk of the brachial plexus (D) would lead to a more extensive pattern of muscle involvement.

Correct Answer: D

Rationale: The correct answer is D: Elbow. Heterotopic ossification is the abnormal formation of bone in soft tissues. In burn patients, the elbow joint is the most common site due to the frequent positioning of the arm during treatment, leading to immobilization and subsequent bone formation. The hip, shoulder, and knee joints are less commonly affected in burn patients. This is because the elbow joint is more prone to prolonged immobilization compared to the other joints, increasing the risk of heterotopic ossification.

Correct Answer: A

Rationale: The correct answer is A: Phonophoresis. Phonophoresis is a technique that uses ultrasound waves to enhance the delivery of medications through the skin. Ultrasound waves help to increase the permeability of the skin, allowing the medications to penetrate deeper into the tissues. This method is commonly used in physical therapy to treat various musculoskeletal conditions. Summary of other choices: B: Diathermy is a therapeutic technique that uses high-frequency electromagnetic currents for deep heating of tissues. C: Iontophoresis is a technique that uses electrical currents to drive medications into the skin. D: None of the above is incorrect as phonophoresis is the correct technique described in the question.

Correct Answer: C

Rationale: The correct answer is C: MRI. MRI is the 'gold standard' for evaluating the rotator cuff because it provides detailed images of soft tissues like tendons and muscles. It offers superior resolution compared to other imaging modalities, allowing for accurate detection of rotator cuff tears and other pathologies. Plain x-ray (A) is not ideal for soft tissue evaluation. Physical exam (B) can provide valuable information but may not definitively diagnose rotator cuff issues. Ultrasound (D) is useful but may not offer the same level of detail and accuracy as MRI for evaluating the rotator cuff.