const {
  Document, Packer, Paragraph, TextRun, Table, TableRow, TableCell,
  HeadingLevel, AlignmentType, BorderStyle, WidthType, ShadingType,
  VerticalAlign, PageNumber, Header, Footer, PageBreak, TableOfContents,
  LevelFormat
} = require('docx');
const fs = require('fs');

// Color palette
const BLUE_DARK = "1F3864";
const BLUE_MID = "2E74B5";
const BLUE_LIGHT = "D6E4F0";
const YELLOW_HL = "FFF2CC";
const GREEN_HL = "E2EFDA";
const RED_HL = "FCE4D6";

function heading1(text) {
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    shading: { type: ShadingType.CLEAR, fill: BLUE_DARK },
    run: { color: "FFFFFF", bold: true, size: 28 },
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}

function heading2(text) {
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    spacing: { before: 300, after: 100 },
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}

function heading3(text) {
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function para(text, options = {}) {
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function bullet(text, bold_prefix = null) {
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function subbullet(text) {
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function highlight(text, fill = YELLOW_HL) {
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    shading: { type: ShadingType.CLEAR, fill },
    spacing: { before: 80, after: 80 },
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function keypoint(label, value) {
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}

function makeTable(headers, rows, headerFill = BLUE_MID) {
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    tableHeader: true,
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      left: { style: BorderStyle.SINGLE, size: 4, color: BLUE_MID },
      right: { style: BorderStyle.SINGLE, size: 4, color: BLUE_MID },
      insideH: { style: BorderStyle.SINGLE, size: 2, color: "C0C0C0" },
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function spacer(lines = 1) {
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}

function divider() {
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    border: { bottom: { style: BorderStyle.SINGLE, size: 6, color: BLUE_MID } },
    spacing: { before: 100, after: 100 },
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}

// ──────────────────────────────────────────────
//  DOCUMENT CONTENT
// ──────────────────────────────────────────────

const doc = new Document({
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  sections: [
    {
      headers: {
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                new TextRun({ text: "ELBOW BIOMECHANICS - STUDY GUIDE", bold: true, color: BLUE_DARK, size: 18 }),
                new TextRun({ text: "  |  Joint Structure & Function", color: "888888", size: 18 }),
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                new TextRun({ text: "Elbow Biomechanics Study Guide  |  Page ", color: "888888", size: 16 }),
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        // =========================================
        // TITLE PAGE
        // =========================================
        new Paragraph({
          children: [new TextRun({ text: "ELBOW BIOMECHANICS", bold: true, size: 52, color: BLUE_DARK, font: "Calibri" })],
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        new Paragraph({
          children: [new TextRun({ text: "Comprehensive Study Guide", size: 34, color: BLUE_MID, font: "Calibri" })],
          alignment: AlignmentType.CENTER,
          spacing: { before: 0, after: 400 },
        }),
        new Paragraph({
          children: [new TextRun({ text: "Based on Joint Structure & Function | Campbell's Operative Orthopaedics | Miller's Review", size: 20, color: "666666", italics: true })],
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          spacing: { before: 0, after: 800 },
        }),

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          alignment: AlignmentType.CENTER,
          spacing: { before: 100, after: 80 },
          indent: { left: 200, right: 200 },
        }),
        makeTable(
          ["Topic", "Key Fact"],
          [
            ["Joints in elbow complex", "3 — Ulnohumeral (hinge) + Radiocapitellar + Proximal Radioulnar (pivot)"],
            ["Type of joint", "Trochoginglymoid (\"sloppy hinge\") — 2 degrees of freedom"],
            ["Normal ROM", "Flexion 0–145° | Pronation 80° | Supination 85°"],
            ["Functional ROM", "30–130° flexion, 50° pronation, 50° supination"],
            ["Close-packed position", "Full extension (elbow) | Full supination (radioulnar)"],
            ["Resting position", "70° flexion, 35° supination"],
            ["Carrying angle", "11° valgus (extension) → 6° varus (flexion)"],
            ["Primary valgus stabilizer", "Anterior bundle of MCL"],
            ["Primary varus stabilizer", "Lateral Ulnar Collateral Ligament (LUCL)"],
            ["Primary stability (overall)", "Ulnohumeral joint — 55–75% of joint restriction"],
          ],
          BLUE_DARK
        ),

        new Paragraph({ children: [new PageBreak()] }),

        // =========================================
        // SECTION 1: ANATOMY
        // =========================================
        new Paragraph({
          text: "1. OSSEOUS ANATOMY",
          heading: HeadingLevel.HEADING_1,
          spacing: { before: 200, after: 150 },
        }),

        heading2("1.1 Bones of the Elbow Complex"),
        para("Three bones form the elbow: the Humerus, Radius, and Ulna. These create three articulations enclosed within a single joint capsule."),

        spacer(),
        heading3("Distal Humerus"),
        bullet("Trochlea (medial) - articular surface that articulates with the trochlear notch of the ulna; shaped like a pulley"),
        bullet("Capitulum (lateral) - rounded surface articulating with the radial head; separated from trochlea by a shallow sulcus"),
        bullet("Olecranon fossa (posterior) - receives olecranon process in full extension"),
        bullet("Coronoid fossa (anterior) - receives coronoid process in full flexion"),
        bullet("Radial fossa (anterior) - receives radial head in full flexion"),
        bullet("Medial epicondyle - attachment site for common flexor tendon & MCL"),
        bullet("Lateral epicondyle - attachment site for common extensor tendon & LCL complex"),

        spacer(),
        heading3("Proximal Ulna"),
        bullet("Trochlear notch - articulates with humerus trochlea; primary elbow joint"),
        bullet("Olecranon process - bony lever for triceps; limits extension"),
        bullet("Coronoid process - limits extension; anterior MCL attaches to sublime tubercle"),
        bullet("Radial notch - articulates with radial head (proximal radioulnar joint)"),

        spacer(),
        heading3("Proximal Radius"),
        bullet("Radial head - disc-shaped; articulates with capitulum and radial notch of ulna"),
        bullet("Radial tuberosity - attachment site for biceps brachii tendon"),

        spacer(),
        highlight("KEY POINT: The supratrochlear septum separates the olecranon and coronoid fossae — a thin, transparent lamina of bone. These three fossae provide stability by housing the bony processes at extremes of motion.", BLUE_LIGHT),

        spacer(),
        heading2("1.2 Carrying Angle"),
        para("The carrying angle is the valgus angulation of the forearm relative to the arm when the elbow is extended."),
        makeTable(
          ["Position", "Carrying Angle", "Clinical Note"],
          [
            ["Full extension", "~11° valgus", "Normal alignment; cubitus valgus if increased"],
            ["Full flexion", "~6° varus", "Angle reverses due to trochlear spiral"],
            ["Cubitus valgus", "> 15° valgus", "May cause tardy ulnar nerve palsy"],
            ["Cubitus varus", "< 5° or varus", "\"Gunstock deformity\" - common after supracondylar fracture"],
          ]
        ),

        new Paragraph({ children: [new PageBreak()] }),

        // =========================================
        // SECTION 2: JOINTS & KINEMATICS
        // =========================================
        new Paragraph({
          text: "2. JOINTS & KINEMATICS",
          heading: HeadingLevel.HEADING_1,
          spacing: { before: 200, after: 150 },
        }),

        heading2("2.1 The Three Articulations"),
        makeTable(
          ["Joint", "Type", "Motion", "Primary Role"],
          [
            ["Ulnohumeral", "Ginglymoid (hinge)", "Flexion / Extension", "Primary stability; 55-75% joint restriction"],
            ["Radiocapitellar", "Trochoid (pivot)", "Flexion/Extension + rotation", "Valgus stress resistance; vertical load transfer"],
            ["Proximal Radioulnar", "Trochoid (pivot)", "Pronation / Supination", "Forearm rotation; stabilized by annular ligament"],
          ]
        ),
        spacer(),
        highlight("The elbow complex as a whole is a trochoginglymoid joint (also called a \"sloppy hinge\") with 2 degrees of freedom: flexion-extension AND pronation-supination.", YELLOW_HL),

        spacer(),
        heading2("2.2 Axis of Rotation"),
        bullet("Flexion-extension axis: passes through the center of the capitellum and trochlea (lateral view)"),
        bullet("This axis is 2–3 mm in diameter, located in the center of the trochlea"),
        bullet("Axis lies ANTERIOR to the humeral midline - along the anterior cortex line"),
        bullet("Forearm pronation/supination axis: longitudinal axis running through the radial head to the distal ulna"),
        bullet("The carrying angle changes due to the oblique trochlear orientation - this is normal kinematics"),

        spacer(),
        heading2("2.3 Normal & Functional Range of Motion"),
        makeTable(
          ["Motion", "Normal ROM", "Functional ROM", "Notes"],
          [
            ["Flexion", "0–145°", "30–130°", "Limited by soft tissue apposition"],
            ["Extension", "0° (some have 5–10° hyperextension)", "0–30°", "Limited by olecranon impingement"],
            ["Pronation", "~80°", "~50°", "Radioulnar joint rotation"],
            ["Supination", "~85°", "~50°", "Radioulnar joint rotation"],
          ]
        ),

        spacer(),
        heading2("2.4 End-Feel & Limiting Structures"),
        makeTable(
          ["Motion", "End-Feel", "Primary Limiting Structure"],
          [
            ["Flexion (passive)", "Soft (normal)", "Soft tissue apposition (forearm to arm)"],
            ["Flexion (active)", "Firm", "Active insufficiency of biceps (two-joint)"],
            ["Extension", "Hard/Bony", "Olecranon in olecranon fossa"],
            ["Supination", "Firm", "Ligamentous tension"],
            ["Pronation", "Hard/Firm", "Bony contact + ligamentous"],
          ]
        ),

        spacer(),
        highlight("Close-packed position = Full Extension (maximum bony congruity). Resting position = 70° flexion, 35° supination.", GREEN_HL),

        new Paragraph({ children: [new PageBreak()] }),

        // =========================================
        // SECTION 3: LIGAMENTOUS STABILITY
        // =========================================
        new Paragraph({
          text: "3. LIGAMENTOUS STABILITY",
          heading: HeadingLevel.HEADING_1,
          spacing: { before: 200, after: 150 },
        }),

        heading2("3.1 Medial Collateral Ligament (MCL) Complex"),
        para("Also called the Ulnar Collateral Ligament (UCL). Consists of THREE bundles:"),

        spacer(),
        makeTable(
          ["Bundle", "Origin", "Insertion", "Primary Function"],
          [
            ["Anterior bundle (AOL)", "Anterior medial epicondyle", "Sublime tubercle of coronoid", "PRIMARY valgus restraint throughout functional ROM"],
            ["Posterior bundle (POL)", "Posterior medial epicondyle", "Medial olecranon", "Primary valgus restraint at MAXIMAL flexion"],
            ["Transverse bundle (Cooper's)", "Olecranon", "Coronoid process", "Minimal contribution; deepens socket"],
          ]
        ),

        spacer(),
        heading3("MCL Function by Elbow Position"),
        bullet("Full extension: MCL, joint capsule, and ulnohumeral articulation share valgus stress equally"),
        bullet("Flexion (functional ROM): Anterior MCL is the prime valgus stabilizer"),
        bullet("90° flexion: Anterior MCL becomes primary - bony contribution is less in mid-flexion"),
        bullet("Maximal flexion: Posterior bundle takes over as primary valgus restraint"),
        bullet("Distraction: MCL complex is the dominant soft-tissue restraint in flexion"),

        spacer(),
        highlight("CLINICAL PEARL: MCL tear/attenuation is the most common cause of medial elbow instability in overhead athletes (pitchers, javelin throwers). Tommy John surgery = UCL reconstruction.", YELLOW_HL),

        spacer(),
        heading2("3.2 Lateral Collateral Ligament (LCL) Complex"),
        para("Consists of FOUR components:"),
        bullet("Radial Collateral Ligament (RCL) - fan-shaped; from lateral epicondyle"),
        bullet("Lateral Ulnar Collateral Ligament (LUCL) - from posterior lateral epicondyle to crista supinatoris of proximal ulna"),
        bullet("Accessory Collateral Ligament"),
        bullet("Annular Ligament - encircles radial head; maintains radioulnar articulation"),

        spacer(),
        heading3("LCL Function"),
        bullet("LUCL is the PRIMARY restraint to varus stress and external rotational stress throughout elbow motion"),
        bullet("LUCL injury → Posterolateral Rotatory Instability (PLRI)"),
        bullet("Varus stress in extension: resisted equally by joint articulation, LUCL, and capsule"),
        bullet("Varus stress in flexion: 75% resisted by joint articulation alone"),

        spacer(),
        heading2("3.3 Joint Capsule"),
        bullet("Anterior capsule: resists anterior displacement of distal humerus; provides distraction resistance in extension"),
        bullet("Posterior capsule: taut in extension; contributes to valgus/varus stability in extension"),
        bullet("At 90° flexion: capsule provides little resistance to distraction"),
        bullet("Resting capsular volume: ~25 mL; intra-articular swelling causes semi-flexed posture (~80°)"),

        spacer(),
        highlight("STABILITY SUMMARY TABLE", BLUE_LIGHT),
        makeTable(
          ["Stress Type", "Position", "Primary Restraint", "Secondary Restraint"],
          [
            ["Valgus", "Extension", "MCL (ant. bundle)", "Capsule + joint surface (equal thirds)"],
            ["Valgus", "Flexion (30-120°)", "Anterior MCL bundle", "Radial head"],
            ["Valgus", "Max flexion", "Posterior MCL bundle", "Ant. bundle + capsule"],
            ["Varus", "Extension", "Joint articulation", "LCL + capsule (equal thirds)"],
            ["Varus", "Flexion", "Joint articulation (75%)", "LUCL"],
            ["Distraction", "Extension", "Anterior capsule", "MCL + LCL"],
            ["Distraction", "Flexion", "MCL complex", "Minimal capsule contribution"],
          ]
        ),

        new Paragraph({ children: [new PageBreak()] }),

        // =========================================
        // SECTION 4: MUSCLES & FORCE COUPLES
        // =========================================
        new Paragraph({
          text: "4. MUSCLES & FORCE PRODUCTION",
          heading: HeadingLevel.HEADING_1,
          spacing: { before: 200, after: 150 },
        }),

        heading2("4.1 Flexor Group"),
        makeTable(
          ["Muscle", "Origin", "Insertion", "Joints Crossed", "Notes"],
          [
            ["Brachialis", "Anterior distal humerus", "Coronoid process / ulnar tuberosity", "1 (elbow only)", "Strongest elbow flexor; true one-joint muscle"],
            ["Biceps brachii (long head)", "Supraglenoid tubercle", "Radial tuberosity", "2 (shoulder + elbow)", "Subject to active insufficiency in elbow flexion"],
            ["Biceps brachii (short head)", "Coracoid process", "Radial tuberosity", "2 (shoulder + elbow)", "Also powerful supinator"],
            ["Brachioradialis", "Lateral supracondylar ridge", "Styloid process of radius", "1 (elbow)", "Most effective with forearm in neutral rotation"],
          ]
        ),

        spacer(),
        heading2("4.2 Extensor Group"),
        makeTable(
          ["Muscle", "Origin", "Insertion", "Joints Crossed", "Notes"],
          [
            ["Triceps brachii (long head)", "Infraglenoid tubercle of scapula", "Olecranon process", "2 (shoulder + elbow)", "Two-joint; passive tension limits elbow flexion"],
            ["Triceps brachii (lateral head)", "Posterior humerus (above radial groove)", "Olecranon process", "1", "Powerful extensor"],
            ["Triceps brachii (medial head)", "Posterior humerus (below radial groove)", "Olecranon process", "1", "Most active throughout extension range"],
            ["Anconeus", "Posterior lateral epicondyle", "Lateral olecranon", "1", "Assists extension; provides lateral stability"],
          ]
        ),

        spacer(),
        heading2("4.3 Two-Joint Muscle Concepts (CRITICAL)"),

        heading3("Active Insufficiency"),
        para("A two-joint muscle becomes too SHORT to generate effective force when it is shortened simultaneously at both joints it crosses."),
        bullet("Example: Biceps brachii during combined elbow flexion + shoulder flexion"),
        bullet("The muscle reaches active insufficiency - it cannot generate adequate tension"),
        bullet("This is why grip strength decreases when elbow is fully flexed with shoulder also flexed"),

        spacer(),
        heading3("Passive Insufficiency"),
        para("A two-joint muscle becomes too LONG/TIGHT when it is stretched simultaneously across both joints, limiting range of motion at one or both joints."),
        bullet("Example: Long head of triceps during elbow flexion when shoulder is also extended"),
        bullet("The passive tension from the overstretched triceps LIMITS elbow flexion range"),
        bullet("This is demonstrated in Figure 8-16A from the textbook image"),

        spacer(),
        makeTable(
          ["Concept", "Muscle State", "Mechanism", "Clinical Example"],
          [
            ["Active insufficiency", "Too short at both joints", "Cannot generate adequate contractile force", "Weak elbow flexion when shoulder is flexed + elbow fully flexed"],
            ["Passive insufficiency", "Too long/stretched at both joints", "Passive tension limits ROM", "Reduced elbow flexion when shoulder is extended (triceps long head)"],
          ]
        ),

        spacer(),
        highlight("REMEMBER: Active insufficiency = muscle too short to contract well. Passive insufficiency = muscle too stretched to allow full ROM.", YELLOW_HL),

        spacer(),
        heading2("4.4 Factors Affecting Muscle Force Output"),
        bullet("Physiological Cross-Sectional Area (PCSA) - greatest determinant of maximum force-producing capacity"),
        bullet("Number of joints crossed - one-joint muscles are more efficient force generators"),
        bullet("Muscle length-tension relationship - optimal force produced at resting length"),
        bullet("Velocity of contraction - slower contractions allow greater force production"),
        bullet("Joint angle - changes the mechanical advantage (moment arm) throughout ROM"),
        bullet("Co-contractions of flexors and extensors provide dynamic elbow stability"),

        spacer(),
        heading2("4.5 Muscle Action During Functional Activities"),
        bullet("During pulling: biceps, brachialis, and elbow flexors are dominant"),
        bullet("During pushing: triceps and elbow extensors generate force"),
        bullet("Body weight support (pushing up from chair): elbow extensors resist 300% body weight forces"),
        bullet("Throwing: valgus stress at medial elbow can reach 64 Nm - approaches MCL failure load"),
        bullet("Co-contractions at the wrist and hand amplify elbow stability during power grips"),

        new Paragraph({ children: [new PageBreak()] }),

        // =========================================
        // SECTION 5: JOINT REACTION FORCES
        // =========================================
        new Paragraph({
          text: "5. JOINT REACTION FORCES",
          heading: HeadingLevel.HEADING_1,
          spacing: { before: 200, after: 150 },
        }),

        heading2("5.1 Forces at the Elbow"),
        para("Joint reaction forces (JRF) at the elbow depend on the load carried, muscle activity, and joint position."),

        makeTable(
          ["Activity", "Approximate JRF", "Notes"],
          [
            ["Carrying a light load (hand)", "~3x load weight", "Amplified by short forearm lever arm"],
            ["Push-up position", "~45% body weight", "Compressive load through radiocapitellar joint"],
            ["Throwing (baseball)", "~300-500 N compression", "Plus significant valgus torque (~64 Nm)"],
            ["Activities of daily living", "0.3–3.0x body weight", "Range depending on task type"],
          ]
        ),

        spacer(),
        heading2("5.2 Radiocapitellar vs. Ulnohumeral Load Sharing"),
        bullet("Radiocapitellar joint: transmits ~60% of longitudinal compressive load"),
        bullet("Ulnohumeral joint: primary constraint to valgus/varus and rotation"),
        bullet("Radial head resection → increased MCL stress (iatrogenic valgus instability)"),
        bullet("With intact radial head: radiocapitellar joint is secondary valgus stabilizer"),

        spacer(),
        highlight("CLINICAL NOTE: When MCL is deficient, the radial head becomes the primary valgus stabilizer. NEVER resect the radial head in a patient with MCL tear without reconstruction!", RED_HL),

        new Paragraph({ children: [new PageBreak()] }),

        // =========================================
        // SECTION 6: CLINICAL CORRELATIONS
        // =========================================
        new Paragraph({
          text: "6. CLINICAL CORRELATIONS",
          heading: HeadingLevel.HEADING_1,
          spacing: { before: 200, after: 150 },
        }),

        heading2("6.1 Elbow Instability Patterns"),
        makeTable(
          ["Instability Type", "Injured Structure", "Clinical Test", "Notes"],
          [
            ["Medial (valgus) instability", "Anterior MCL bundle", "Valgus stress test at 30° flexion", "Common in overhead athletes"],
            ["Lateral (varus) instability", "LUCL", "Varus stress test", "Less common; lateral pivot shift test"],
            ["Posterolateral rotatory instability (PLRI)", "LUCL (primary)", "Lateral pivot shift test", "Apprehension/subluxation of radial head"],
            ["Simple dislocation", "LCL then MCL (Horii circle)", "Imaging", "Posterolateral dislocation most common"],
          ]
        ),

        spacer(),
        heading2("6.2 Elbow Position & Intra-articular Swelling"),
        bullet("Intra-articular effusion causes the patient to hold elbow at ~80° flexion"),
        bullet("80° flexion = position of MINIMUM joint capsule tension"),
        bullet("Each mL of intra-articular fluid decreases ROM by ~2.1°"),
        bullet("Close-packed position (full extension) has maximum capsular tension - MOST painful with effusion"),

        spacer(),
        heading2("6.3 Common Tendinopathies"),
        makeTable(
          ["Condition", "Structure Involved", "Mechanism", "Provocative Test"],
          [
            ["Lateral epicondylitis (\"Tennis Elbow\")", "Common extensor tendon (ECRB mainly)", "Repetitive wrist extension under load", "Cozen's test, Mill's test"],
            ["Medial epicondylitis (\"Golfer's Elbow\")", "Common flexor-pronator tendon", "Repetitive wrist flexion/pronation", "Resisted wrist flexion + pronation"],
            ["Distal biceps tendinopathy/rupture", "Distal biceps tendon at radial tuberosity", "Forced extension during active flexion", "Hook test, squeeze test"],
            ["Triceps tendinopathy/rupture", "Distal triceps at olecranon", "Eccentric overload, direct trauma", "Resisted extension, palpation"],
          ]
        ),

        spacer(),
        heading2("6.4 Nerve Relationships"),
        bullet("Ulnar nerve: passes posterior to medial epicondyle in cubital tunnel - vulnerable in valgus stress"),
        bullet("Radial nerve: passes anterior to radial head - vulnerable in radial head fractures/dislocations"),
        bullet("Median nerve: passes anterior to elbow - vulnerable in supracondylar fractures (anterior interosseous nerve)"),
        bullet("Tardy ulnar nerve palsy: late complication of cubitus valgus deformity from old lateral condyle fractures"),

        new Paragraph({ children: [new PageBreak()] }),

        // =========================================
        // SECTION 7: QUICK-RECALL MEMORY AIDS
        // =========================================
        new Paragraph({
          text: "7. MEMORY AIDS & QUICK RECALL",
          heading: HeadingLevel.HEADING_1,
          spacing: { before: 200, after: 150 },
        }),

        heading2("7.1 Mnemonic: ELBOW FACTS"),
        bullet("E - Extension = close-packed position"),
        bullet("L - Ligament (anterior MCL) = primary valgus stabilizer"),
        bullet("B - Brachialis = strongest ONE-joint flexor (not biceps!)"),
        bullet("O - Olecranon = bony block that limits extension"),
        bullet("W - Width of axis = 2–3 mm through center of trochlea"),
        spacer(),
        bullet("F - Flexion functional range = 30–130°"),
        bullet("A - Active insufficiency = biceps too short when flexed at both joints"),
        bullet("C - Carrying angle = 11° valgus in extension"),
        bullet("T - Trochoginglymoid = 2 degrees of freedom"),
        bullet("S - Swelling → 80° flexion (minimum capsular tension)"),

        spacer(),
        heading2("7.2 Position-Stability Quick Reference"),
        makeTable(
          ["Elbow Position", "Close-packed?", "Capsule Tension", "Best for..."],
          [
            ["Full Extension", "YES", "HIGH", "Bony congruity; avoid with effusion"],
            ["~70-80° Flexion", "NO (resting)", "LOWEST", "Patient comfort with swelling"],
            ["90° Flexion", "NO", "Moderate", "Functional position for most tasks"],
            ["Full Flexion", "NO", "Moderate-High", "Maximum reach tasks"],
          ]
        ),

        spacer(),
        heading2("7.3 One-Sentence Summaries"),
        highlight("The elbow is a trochoginglymoid joint (hinge + pivot) with the MCL as the primary valgus stabilizer and the LUCL as the primary varus/rotational stabilizer.", BLUE_LIGHT),
        highlight("The brachialis is the true workhorse flexor; biceps adds supination power but is limited by active insufficiency.", GREEN_HL),
        highlight("Intra-articular swelling = semi-flexed posture (~80°) because this minimizes joint capsule tension.", YELLOW_HL),
        highlight("Two-joint muscles (biceps, triceps long head) are subject to active AND passive insufficiency depending on position of both joints.", RED_HL),

        spacer(),

        // =========================================
        // SECTION 8: PRACTICE QUESTIONS
        // =========================================
        new Paragraph({
          text: "8. SELF-ASSESSMENT QUESTIONS",
          heading: HeadingLevel.HEADING_1,
          spacing: { before: 200, after: 150 },
        }),

        heading2("Questions"),
        para("1. A pitcher complains of medial elbow pain and instability with throwing. Which specific bundle of which ligament is most likely injured?"),
        spacer(),
        para("2. Why does a patient with elbow joint effusion hold their arm at ~80° flexion rather than full extension?"),
        spacer(),
        para("3. What is the difference between active and passive insufficiency? Give an elbow muscle example for each."),
        spacer(),
        para("4. What are the three articulations of the elbow complex, and what are their respective joint types?"),
        spacer(),
        para("5. Describe the carrying angle of the elbow and how it changes from extension to flexion."),
        spacer(),
        para("6. Why should the radial head NOT be resected in a patient with a concurrent MCL tear?"),
        spacer(),
        para("7. What is the close-packed position of the elbow, and what structures provide stability in this position?"),

        spacer(2),
        heading2("Answers"),
        para("1. Anterior bundle of the Medial Collateral Ligament (MCL/UCL) - primary restraint to valgus stress in functional ROM."),
        spacer(),
        para("2. ~80° flexion minimizes joint capsule tension. Full extension (close-packed) would maximally stretch the capsule, increasing pain. Each mL of fluid decreases ROM by 2.1°."),
        spacer(),
        para("3. Active insufficiency = a two-joint muscle is too short at both joints to generate effective contraction (e.g., biceps during combined shoulder + elbow flexion). Passive insufficiency = a two-joint muscle is too stretched at both joints to allow full ROM (e.g., triceps long head limiting elbow flexion when shoulder is also extended)."),
        spacer(),
        para("4. (1) Ulnohumeral - ginglymoid/hinge; (2) Radiocapitellar - trochoid/pivot; (3) Proximal Radioulnar - trochoid/pivot. Together = trochoginglymoid."),
        spacer(),
        para("5. ~11° valgus in full extension; changes to ~6° varus in full flexion. This is due to the oblique orientation of the humeral trochlea and is normal kinematics."),
        spacer(),
        para("6. When the MCL is torn, the radial head becomes the PRIMARY valgus stabilizer. Removing it leaves no restraint to valgus force, causing catastrophic instability."),
        spacer(),
        para("7. Full extension is close-packed. Stability is provided by: bony congruity (olecranon in fossa), MCL anterior bundle, lateral collateral complex, and anterior joint capsule."),

        spacer(),
        divider(),
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          children: [new TextRun({ text: "Sources: Campbell's Operative Orthopaedics 15th Ed | Miller's Review of Orthopaedics 9th Ed | Imaging Anatomy Vol. 3 | Joint Structure & Function (Levangie & Norkin)", italics: true, size: 18, color: "888888" })],
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