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Q1: What bones and ligaments form the elbow joint?
The elbow is a hinged joint formed by articulations between three bones: the humerus, radius, and ulna. It is stabilized by the lateral and medial collateral ligament complexes. This stable structure allows for controlled upper extremity mobility while limiting range of motion compared to the shoulder.
Q2: How do you perform palpation during an elbow examination?
Palpation localizes pain to anterior, posterior, medial, or lateral regions. Start anteriorly by finding the biceps tendon in the cubital fossa, then assess the median nerve and joint capsule. Progress posteriorly to palpate the triceps, olecranon process, and olecranon bursa. Medially, locate the epicondyle, flexor tendons, MCL, and ulnar nerve. Laterally, assess the epicondyle, extensor tendons, and radial head.
Q3: What are the normal ranges of motion for elbow flexion, extension, pronation, and supination?
Normal elbow extension is 0 degrees at full straightening. Flexion ranges approximately 150 degrees when touching the hand to the shoulder. Pronation (palms facing down) is about 80-90 degrees, and supination (palms facing up) reaches approximately 90 degrees. Comparing both sides helps identify mechanical blocks or stiffness from injury or arthritis.
Q4: What muscle groups control elbow movement and where do they attach?
Flexor muscles include biceps brachii, brachialis, and brachioradialis. Extension involves triceps brachii and anconeus. Pronation engages brachioradialis and pronator teres, while supination involves biceps brachii, brachioradialis, and supinator muscles. The lateral epicondyle anchors extensors, and the medial epicondyle anchors flexor and pronator muscles.
Q5: How do resisted motion tests help diagnose epicondylitis?
Resisted motion tests assess muscle strength and identify tendonitis or epicondylitis. Resisting pronation aggravates medial epicondylitis since pronator tendons attach there. Resisting wrist extension and supination aggravates lateral epicondylitis. Resisting wrist flexion and middle finger extension tests medial and lateral structures respectively, helping clinicians localize inflammation to specific epicondyles.
Q6: What special tests evaluate collateral ligament stability in the elbow?
Valgus stress testing assesses the medial collateral ligament (MCL), which is injured more commonly than the lateral collateral ligament (LCL). Varus stress tests the LCL. The milking maneuver creates valgus stress by having the patient bend the elbow to 90 degrees, fully supinate the hand with thumb extended, then pull laterally using the opposite arm to test MCL integrity.
Q7: What are tennis elbow and golfer's elbow, and how do they relate to elbow anatomy?
Lateral epicondylitis, called tennis elbow, occurs when extensors attaching to the lateral epicondyle become inflamed, commonly in tennis players. Medial epicondylitis, or golfer's elbow, involves inflammation of flexor and pronator muscles attaching to the medial epicondyle, frequently seen in golfers. Both conditions result from repetitive motion and can be identified through careful palpation and resisted motion testing during physical examination.