Chapter 5: Humerus and Shoulder Study Guide

Chapter 5 Humerus and Shoulder Girdle Here\'s a more organized and simplified study guide for your test on the shoulder girdle, humerus, clavicle, scapula, and shoulder joints. I\'ve broken it down into key points with headings, so you can quickly review. \-\-- \#\#\# \*\*Proximal Humerus\*\* \...

Chapter 5 Humerus and Shoulder Girdle Here\'s a more organized and simplified study guide for your test on the shoulder girdle, humerus, clavicle, scapula, and shoulder joints. I\'ve broken it down into key points with headings, so you can quickly review. \-\-- \#\#\# \*\*Proximal Humerus\*\* \- \*\*Largest bone of the upper limb\*\* \- Consists of a body and two ends: one articulates with the scapula (shoulder joint). \- \*\*Anatomy\*\*: \- \*\*Head\*\*: Articulates with the scapula (shoulder joint). \- \*\*Anatomic Neck\*\*: Below and lateral to the head; connects with tubercles. \- \*\*Greater & Lesser Tubercle\*\*: Points for muscle attachment. \- \*\*Surgical Neck\*\*: Common fracture site. \- \*\*Intertubercular Sulcus (Bicipital Groove)\*\*: Deep groove between tubercles. \- \*\*Deltoid Tuberosity\*\*: Raised area on the body where deltoid muscle attaches. \-\-- \#\#\# \*\*Shoulder Girdle\*\* \- \*\*Bones\*\*: Clavicle & Scapula. \- \*\*Function\*\*: Connects the upper limbs to the trunk. \- \*\*Anterior Connection\*\*: Sternum (at sternoclavicular joint). \- \*\*Posterior Connection\*\*: Scapula connects via muscles (no bone-to-bone contact). \- \*\*Joints\*\*: \- \*\*SC Joint\*\*: Sternoclavicular joint (between clavicle and sternum). \- \*\*AC Joint\*\*: Acromioclavicular joint (between acromion and clavicle). \-\-- \#\#\# \*\*Clavicle\*\* \- \*\*Long Bone\*\*: Sits just above the first rib. \- \*\*Acromial Extremity\*\*: Lateral end, connects with acromion of scapula (AC joint). \- \*\*Sternal Extremity\*\*: Medial end, connects with manubrium of sternum (SC joint). \- \*\*Double Curve\*\*: Provides strength. \- \*\*Male vs Female\*\*: Males tend to have thicker, more curved clavicles, while females have shorter, less curved clavicles. \-\-- \#\#\# \*\*Scapula (Shoulder Blade)\*\* \- \*\*Flat Bone\*\*: Forms the back of the shoulder girdle. \- \*\*Shape\*\*: Triangular. \- \*\*Two Surfaces\*\*: \- \*\*Costal (Anterior)\*\*: Contains the subscapular fossa. \- \*\*Dorsal (Posterior)\*\*: Divided by the spinous process. \- \*\*Three Borders\*\*: \- \*\*Lateral\*\*: From glenoid cavity to inferior angle. \- \*\*Medial\*\*: From superior to inferior angles. \- \*\*Superior\*\*: From superior angle to coracoid process. \- \*\*Three Angles\*\*: \- \*\*Superior\*\*: Junction of superior and medial borders. \- \*\*Inferior\*\*: Junction of medial and lateral borders (near 7th rib). \- \*\*Lateral\*\*: At the glenoid cavity. \-\-- \#\#\# \*\*Shoulder Joint\*\* \- \*\*Type\*\*: Ball-and-socket. \- \*\*Classification\*\*: \- \*\*Function\*\*: Diarthrodial (freely movable). \- \*\*Anatomy\*\*: Synovial. \- \*\*Motion\*\*: Capable of all movements (flexion, extension, rotation, etc.). \- \*\*Parts\*\*: \- \*\*Proximal Humerus\*\*: Head, anatomic neck, tubercles, surgical neck, body. \- \*\*Glenoid Cavity\*\*: Shallow depression in the scapula that the humeral head fits into. \-\-- \#\#\# \*\*Radiographic Procedures\*\* \#\#\#\# \*\*Humerus AP Projection\*\* \- \*\*Position\*\*: \- Erect or supine. \- Align the humerus with the IR. \- Abduct arm slightly and supinate the hand (epicondyles parallel to IR). \- \*\*Central Ray\*\*: Perpendicular to midpoint of humerus. \- \*\*Collimation\*\*: Include the shoulder, humerus, and elbow joints. \#\#\#\# \*\*Humerus Lateral Projection\*\* \- \*\*Position\*\*: \- Erect or supine. \- Internally rotate arm to position epicondyles perpendicular to the IR. \- \*\*Central Ray\*\*: Perpendicular to midpoint of humerus. \- \*\*Collimation\*\*: Include shoulder and elbow joints. \#\#\#\# \*\*Transthoracic Lateral Projection (Trauma)\*\* \- \*\*Position\*\*: \- Lateral with the side of interest closest to IR. \- Arm in neutral rotation. \- Raise opposite arm to avoid superimposition of shoulders. \- \*\*Central Ray\*\*: Perpendicular to mid-diaphysis of humerus. \- \*\*Collimation\*\*: Focus on the humerus and thorax area. \-\-- \#\#\# \*\*Patient Prep and Instructions\*\* \- \*\*Prep\*\*: Remove jewelry, artifacts, and clothing that can block radiographic images. \- \*\*Patient Position\*\*: Can be upright or supine. Make sure the shoulder and elbow joints are equidistant from the ends of the IR. \- \*\*Instructions\*\*: Suspend respiration during exposures to avoid motion. \- \*\*Radiation Protection\*\*: Use proper collimation and lead shielding. \-\-- \#\#\# \*\*Additional Tips\*\* \- \*\*Collimation\*\*: Always collimate tightly to avoid unnecessary radiation exposure. \- \*\*Proper Exposure\*\*: Ensure proper technique for optimal image quality with clear bony trabecular markings. \- \*\*Breathing\*\*: For most radiographs, suspend respiration. However, use a breathing technique for transthoracic projections. \-\-- \#\#\# \*\*Key Anatomy and Radiograph Tips\*\* \- \*\*Humerus AP\*\*: Greater tubercle laterally, humeral head partially visible medially. \- \*\*Humerus Lateral\*\*: Epicondyles superimposed, lesser tubercle in profile. \- \*\*Transthoracic Lateral\*\*: Entire humerus visualized, no superimposition from opposite humerus. \-\-- Review these key sections, and you should be well-prepared for your test tomorrow! Let me know if you need any more details or clarifications. To help you study effectively for your test tomorrow, I\'ve organized the information into sections, focusing on key points, patient positions, and image evaluation criteria. You can use this as a quick reference for your study. \-\-- \#\#\# \*\*Shoulder -- Internal Rotation (AP) (Non-Trauma)\*\* \- \*\*Patient Position\*\*: Rotate slightly toward the affected shoulder, place scapula parallel to IR. \- \*\*Part Position\*\*: Flex elbow slightly, rotate arm internally, and rest the back of the hand on the hip. \- \*\*CR\*\*: Perpendicular, 1 inch inferior to coracoid process. \- \*\*Collimation\*\*: 10 × 12 inches (24 × 30 cm). \- \*\*Image Criteria\*\*: \- Lesser tubercle in profile, pointing medially. \- Greater tubercle superimposed over humeral head. \- More humeral overlap of glenoid cavity than in external/neutral positions. \-\-- \#\#\# \*\*Shoulder -- External Rotation (AP) (Non-Trauma)\*\* \- \*\*Patient Position\*\*: Rotate slightly toward the affected shoulder, scapula parallel to IR. \- \*\*Part Position\*\*: Flex elbow, rotate arm externally, and supinate hand. \- \*\*CR\*\*: Perpendicular, 1 inch inferior to coracoid process. \- \*\*Collimation\*\*: 10 × 12 inches (24 × 30 cm). \- \*\*Image Criteria\*\*: \- Humeral head and greater tubercle in profile. \- Glenoid cavity in profile, slight overlap with humeral head. \- Bony trabecular detail. \-\-- \#\#\# \*\*Shoulder -- Neutral Position (AP) (Trauma)\*\* \- \*\*Patient Position\*\*: Arm in neutral position, palm resting on thigh. \- \*\*CR\*\*: Perpendicular, directed to mid-scapulohumeral joint (¾ inch inferior to coracoid process). \- \*\*Collimation\*\*: Adjust to soft tissue margins. \- \*\*Image Criteria\*\*: \- Greater tubercle partially superimposing humeral head. \- Humeral head partially in profile. \- Slight overlap of humeral head and glenoid. \-\-- \#\#\# \*\*Shoulder -- Inferosuperior Axial (Lawrence Method) (Non-Trauma)\*\* \- \*\*Patient Position\*\*: Supine, arm abducted 90° from body, external rotation (palm up). \- \*\*CR\*\*: Medial angle of 25°-30°, centered to axilla and humeral head. \- \*\*Collimation\*\*: Close on four sides. \- \*\*Image Criteria\*\*: \- Lateral view of proximal humerus and scapulohumeral cavity. \- Coracoid process and lesser tubercle in profile. \- Superimposed superior and inferior borders of the glenoid cavity. \-\-- \#\#\# \*\*Shoulder -- Oblique (Grashey Method) (Non-Trauma)\*\* \- \*\*Patient Position\*\*: Supine or upright, RPO or LPO, 35°-45° posterior oblique position. \- \*\*CR\*\*: Perpendicular to glenoid cavity, entering 2 inches medial and inferior to the superolateral border of the shoulder. \- \*\*Collimation\*\*: 8 × 10 inches (18 × 24 cm). \- \*\*Image Criteria\*\*: \- Open joint space between humeral head and glenoid cavity. \- Glenoid cavity in profile. \- Bony trabecular detail. \-\-- \#\#\# \*\*Shoulder -- Transthoracic Lateral (Lawrence) (Trauma)\*\* \- \*\*Patient Position\*\*: Supine or upright lateral, affected limb closer to IR. \- \*\*CR\*\*: Perpendicular, midcoronal plane at surgical neck. \- If the unaffected shoulder cannot be elevated, angle the CR 10°-15° cephalad. \- \*\*Collimation\*\*: Close to area of interest. \- \*\*Image Criteria\*\*: \- Proximal humerus, scapula, clavicle, and humerus visible through lung field. \- Scapula superimposed over thoracic spine. \-\-- \#\#\# \*\*Shoulder -- PA Oblique (Scapular Y) (Trauma)\*\* \- \*\*Patient Position\*\*: Upright or recumbent, RAO or LAO. \- \*\*CR\*\*: Perpendicular to scapulohumeral joint (2 inches below AC joint). \- \*\*Collimation\*\*: Close on four sides. \- \*\*Image Criteria\*\*: \- Humeral head and glenoid cavity superimposed. \- Scapula in lateral profile. \- Acromion projected laterally, coracoid potentially below clavicle. \-\-- \#\#\# \*\*Clavicle -- AP & AP Axial\*\* \- \*\*Patient Position\*\*: Upright or supine, arms at sides. \- \*\*CR\*\*: \- AP: Perpendicular to midshaft of clavicle. \- AP Axial: 15°-30° cephalad to mid-clavicle. \- \*\*Collimation\*\*: 8 × 12 inches (18 × 30 cm), ensure AC and SC joints are included. \-\-- \#\#\# \*\*Key Notes for All Shoulder Exams\*\*: \- \*\*Respiration\*\*: Suspend at the end of inhalation to help elevate the clavicles. \- \*\*Collimation\*\*: Always collimate tightly to avoid unnecessary radiation. \- \*\*Positioning\*\*: Proper body rotation is essential for optimal imaging. Ensure scapula, humerus, and clavicle alignment. \-\-- \#\#\# \*\*General Image Evaluation Criteria for Shoulder Radiographs\*\*: \- \*\*Proper Collimation\*\*: Ensure the image includes only the area of interest. \- \*\*Profile Views\*\*: Check for the correct profile of the humeral head, tubercles, and scapula. \- \*\*Superimposition\*\*: Look for proper superimposition of anatomical structures (e.g., humeral head and glenoid cavity). \- \*\*Bony Trabecular Detail\*\*: Confirm clear visibility of bone structures and soft tissues. This guide will help you review the essential details for each exam. Be sure to focus on the patient positioning, CR angles, collimation areas, and image criteria for accurate shoulder imaging. Best of luck on your test! **\#\#\# Scapula Projections** \#\#\#\# 1. \*\*AP Scapula\*\* \- \*\*Patient Position\*\*: \- Consider comfort; upright or supine \- \*\*Part Position\*\*: \- Center scapula to grid \- Abduct arm 90°, supinate hand \- Flex elbow \- \*\*CR\*\*: Perpendicular to 2 inches (5 cm) inferior to coracoid process \- \*\*Collimation\*\*: Closely around scapula area \*\*Evaluation Criteria\*\*: \- Lateral scapula free from rib superimposition \- Scapula horizontal, not slanted \- Scapular details visible, with lung and ribs blurred (shallow breathing) \- Acromion and inferior angle included \- Bony trabecular detail and soft tissues \-\-- \#\#\#\# 2. \*\*Lateral Scapula\*\* \- \*\*Patient Position\*\*: \- Standing or seated in RAO/LAO (45°--60° oblique) \- Scapula centered to grid \- \*\*Part Position\*\*: \- \*\*For Acromion/Coracoid\*\*: Flex elbow, place hand on posterior thorax \- \*\*For Scapula Body\*\*: \- Extend arm or bring across chest \- Lateral and medial borders of scapula perpendicular to IR \- \*\*CR\*\*: Perpendicular to mid-medial border of scapula \- \*\*Collimation\*\*: Closely around scapula area \*\*Evaluation Criteria\*\*: \- Lateral/medial borders of scapula superimposed \- No scapula body superimposition on ribs \- No humeral superimposition \- Inclusion of acromion and inferior angle \- Bony trabecular detail \-\-- **\#\#\# AC Joints (Pearson Method)** \-\-- \#\#\#\# 1. \*\*AP AC Joints (Pearson)\*\* \- \*\*Patient Position\*\*: \- Erect, posterior shoulders against cassette \- Equal weight on both feet, arms at sides, no rotation \- \*\*Part Position\*\*: \- Center IR to CR, top 2 inches (5 cm) above shoulders \- Perform 2 sets of bilateral AC joints: one with weights, one without \- \*\*CR\*\*: \- Bilateral: Perpendicular to midpoint (1 inch above jugular notch) \- Unilateral: 1 inch below affected AC joint \- \*\*Collimation\*\*: Long narrow field, upper border at shoulder soft tissue margins \*\*Evaluation Criteria\*\*: \- Both AC joints, with/without weights, included \- No rotation/leaning \- Clear AC joint separation if present \- Correct weight markers \-\-- \#\#\# Hill-Sachs Defect (Shoulder Dislocation) \- \*\*Definition\*\*: Impacted fracture on the posterolateral humeral head caused by anterior dislocation of the shoulder. \- \*\*Radiographic Methods for Evaluation\*\*: 1\. \*\*Rafert Modification\*\* 2\. \*\*Inferosuperior Axial Projection\*\* 3\. \*\*West Point Method\*\* 4\. \*\*Stryker Notch Method\*\* 5\. \*\*Garth Method\*\*: For assessing acute trauma, posterior dislocations, glenoid fractures, Hill-Sachs defects, and calcifications. \-\-- \#\#\# Other Methods for Shoulder Pathology Evaluation \-\-- \#\#\#\# 1. \*\*AP Oblique (Apple Method)\*\* \- Similar to the \*\*Grashey Method\*\*, but uses weight abduction to show cartilage loss. \#\#\#\# 2. \*\*Superoinferior Axial Projection\*\* \- Evaluates joint relationship between humerus and glenoid cavity. \#\#\#\# 3. \*\*Tangential (Neer Method)\*\* \- PA oblique projection (RAO/LAO) for supraspinatus outlet. \- Diagnoses shoulder impingement by showing coracoacromial arch. \#\#\#\# 4. \*\*AP Axial Projection\*\* \- Evaluates humeral head relationship with glenoid cavity, often for diagnosing posterior dislocations. \#\#\#\# 5. \*\*Tangential (Fisk Modification)\*\* \- Evaluates the intertubercular groove of the humerus. \-\-- \#\#\# Summary Tips for Studying: \- \*\*Review Positioning and CR\*\* for each projection. \- \*\*Practice Image Evaluation Criteria\*\* to understand what to look for in your final images (e.g., clarity, specific anatomical parts). \- \*\*Know Common Pathologies\*\* like Hill-Sachs defects and how each method helps evaluate them. \- \*\*Focus on key projections\*\* for AC joints, scapula, and humerus as they often show up on exams. \-\-- \#\#\# Good luck on your test tomorrow!