History taking for back pain , knee pain and other chief complaints for orthopaedics. Important things to rule out and positive and negative relevances

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I now have rich, comprehensive content from multiple authoritative textbooks. Let me compile a detailed response.

Orthopaedic History Taking: Back Pain, Knee Pain & Other Chief Complaints

General Framework for Any Orthopaedic Complaint

Every orthopaedic history follows a structured SOCRATES + contextual model:

Component	Key Questions
Site	Exact location? Point with one finger.
Onset	Sudden vs. gradual? Precipitating event?
Character	Aching, sharp, burning, shooting, throbbing?
Radiation	Does it travel? Where to?
Associated symptoms	Swelling, stiffness, locking, clicking, weakness, numbness?
Timing	Constant vs. intermittent? Morning stiffness? Night pain?
Exacerbating/Relieving	Movement, rest, posture, analgesics?
Severity	0-10 scale; functional limitation?

Always include: Occupation, handedness (for UL), dominant activity/sport, BMI, prior episodes, prior treatment, medications (especially steroids, anticoagulants), comorbidities (DM, osteoporosis, cancer, immunosuppression), and family history.

1. BACK PAIN - Detailed History Taking

Pain Character & Location

Axial (localised to back): points to muscular, ligamentous, vertebral, disc, or facet origin
Radiation to buttocks/thighs only: often referred from disc or SI joint
True sciatica (below knee, dermatomal): nerve root involvement - ask specifically if it goes below the knee
L4-L5 disc: radiates to dorsum of foot / big toe (L5 dermatome)
L5-S1 disc: radiates to lateral foot / small toe (S1 dermatome)

Critical Pain Features to Ask

Feature	Implication
Worse with sitting, better with standing/lying	Disc herniation
Worse with walking / extension, better with forward flexion / sitting	Spinal stenosis (neurogenic claudication)
Dull aching, worsens with movement, improves with rest	Benign mechanical pain
Night pain, awakens from sleep, unrelenting	RED FLAG - tumour or infection
Worse with coughing, Valsalva, sneezing	Disc herniation
Worsens lying supine	Tumour, AAA, retroperitoneal pathology

RED FLAGS in Spine (Goldman-Cecil Medicine)

Rule these out in every patient with back pain:

History of malignancy (back pain is the initial symptom in majority of spinal mets; 20% have undiagnosed primary)
Unexplained weight loss
Unexplained fever / rigors
Immunosuppression (HIV, steroids, transplant, chemotherapy)
Intravenous drug use (spinal epidural abscess)
Osteoporosis + even minor trauma (compression fracture - especially elderly women, steroid users)
Age < 20 or > 50 years
History of recent surgery / GI / GU procedure (haematogenous seeding)
Progressive neurological deficit (weakness, sensory loss worsening)
Myelopathy signs (bilateral leg weakness, spasticity, clumsiness)
Possible cauda equina syndrome (see below)
Duration > 6 weeks without improvement
Uncontrollable / unrelenting pain despite analgesics and rest
Trauma (any mechanism raising fracture concern)

CAUDA EQUINA SYNDROME - Emergency History (Do Not Miss)

Ask explicitly:

Bladder: retention (inability to void) or incontinence?
Bowel: incontinence or loss of anal tone sensation?
Saddle anaesthesia: numbness in perineum, inner thighs, genitalia?
Progressive bilateral leg weakness or numbness?

Bowel or bladder incontinence combined with back pain is a surgical emergency until proven otherwise. Measure post-void residual (>100 mL is significant). - Tintinalli's Emergency Medicine

Spinal Infection (Discitis/Epidural Abscess) Predictors

Ask about (most significant in descending order per Tintinalli's):

Fever or rigors
Recent antibiotic use (past 30 days - may mask)
Significant spinal pain
IV drug use
Advanced age
Diabetes mellitus
Renal failure, alcoholism, recent skin abscess/UTI/pneumonia

Positive & Negative Likelihood Ratios - Cancer as Cause of LBP

Finding	Sensitivity	Specificity	LR+	LR-
Prior history of cancer	31%	98%	14.7	0.7
Failure to improve after 1 month	31%	90%	3.0	0.77
Age > 50	77%	71%	2.7	0.32
Unexplained weight loss	15%	94%	2.7	0.9
Duration > 1 month	50%	81%	2.6	0.62
No relief with bed rest	90%	46%	1.7	0.21
Nocturnal pain	92%	46%	1.7	0.17
Any of: age >50, hx cancer, weight loss, failure of conservative therapy	100%	60%	2.5	0.0

(Source: Symptom to Diagnosis, 4th Ed)

Functional History (Mandatory)

How far can you walk before pain stops you? (claudication distance - neurogenic vs vascular)
Can you ride a bike without pain? (neurogenic claudication: flexed posture = relief; vascular claudication: cycling also hurts)
Effect on sleep, work, ADLs

2. KNEE PAIN - Detailed History Taking

(Harrison's Principles, 22E; S Das Clinical Surgery, 13E; Campbell's Operative Orthopaedics, 15E)

Core Symptoms to Ask About

"PLAN-CLOGS" mnemonic for knee symptoms:

Pain - location (anterior, medial, lateral, posterior, diffuse)
Locking - true locking (cannot fully extend, springy block) vs. pseudo-locking (pain inhibition)
Activity-related change
Night pain
Clicking / Clunking
Limp / gait change
Oedema (swelling - acute vs. chronic; intra-articular vs. extra-articular)
Giving way
Stiffness (morning stiffness duration)

Anterior Knee Pain

Worse going up/down stairs or sitting for prolonged periods ("cinema sign"): patellofemoral syndrome / OA
Young active patient: patellar tendinopathy, Osgood-Schlatter (tibial tubercle pain in adolescents)

Medial Knee Pain

After awkward twisting: medial meniscus tear
Tender on anteromedial proximal tibia: pes anserine bursitis (common in obese patients, OA, fibromyalgia - often missed)
MCL strain: after valgus stress, lateral blow

Lateral Knee Pain

Lateral meniscus tear, IT band friction syndrome (runners)

Posterior Knee Pain

Baker's cyst (popliteal cyst) - fluctuant swelling behind knee, worse with extension

Mechanical Symptoms

True locking (cannot fully extend, springy block at a fixed angle) = meniscal tear (bucket-handle) until proven otherwise
Giving way = ligamentous instability (ACL most common), patellofemoral maltracking, or quadriceps weakness
Clicking / snapping = may be meniscal, or plica syndrome

"A sensation of giving way or snaps, clicks, catches, or jerks in the knee may be described, or the history may be even more indefinite, with recurrent episodes of pain" - Campbell's Operative Orthopaedics, 15th Ed

Swelling Pattern

Pattern	Suggests
Immediate swelling (within 2 hours of injury)	Haemarthrosis - ACL rupture, osteochondral fracture
Delayed swelling (12-24 hrs after injury)	Meniscal tear (slow synovial reaction)
Chronic fluctuant effusion	OA, RA, crystal arthropathy, chronic meniscal
Horseshoe-shaped swelling around patella	Knee joint effusion (obliterates normal depressions)

Inflammatory vs. Mechanical History

Feature	Mechanical (OA)	Inflammatory (RA, gout, pseudogout)
Morning stiffness	< 30 minutes	> 1 hour
Activity effect	Worse with activity	Often better with movement
Erythema/warmth	Uncommon	Common
Systemic symptoms	Absent	Fever, malaise, other joints
Night pain	Late-stage	Gout attacks often nocturnal

Don't Miss

Referred pain from the hip - always examine the hip in every patient presenting with knee pain. Hip OA / fracture frequently refers to the knee. "Very often a patient with pathology in the hip will complain of pain in the knee" - S Das Clinical Surgery
Gout/pseudogout - acute monoarthritis, warm, erythematous knee
Septic arthritis - fever, hot swollen joint, inability to bear weight - EMERGENCY
DVT - posterior knee / calf swelling, risk factors (immobility, recent surgery)

3. HIP PAIN

Groin pain = intra-articular (OA, AVN, labral tear, fracture)
Greater trochanter pain = trochanteric bursitis / gluteus medius tendinopathy
Posterior buttock pain = piriformis syndrome, SI joint, referred lumbar
FABER test pain = hip / SI joint pathology
Night pain / rest pain = AVN, malignancy
Leg length discrepancy = ask about shoe wear, pelvic tilt
Groin pain radiating down anterior thigh = femoral nerve / L2-L3 involvement

4. SHOULDER PAIN

Painful arc (60-120° of abduction) = rotator cuff / subacromial impingement
Full arc pain = AC joint pathology
Night pain, unable to lie on shoulder = rotator cuff tear, frozen shoulder
Unable to raise arm, dropping arm test = full-thickness rotator cuff tear
Instability / apprehension = glenohumeral instability
Stiffness in all planes = adhesive capsulitis (frozen shoulder)
Occupation: overhead work, throwing athletes
Age: RCT tears commoner > 50 years; instability commoner < 30 years

5. FOOT & ANKLE PAIN

First step pain in the morning, heel pain = plantar fasciitis
Lateral ankle pain after inversion injury = lateral ligament complex sprain
Bony prominence dorsal foot = exostosis
Numbness in toes = tarsal tunnel syndrome, peripheral neuropathy - check diabetes history
Gradual flat foot deformity = tibialis posterior tendon dysfunction

6. General Positive & Negative History Points in Orthopaedics

Positive History Points (Increase Suspicion for Serious Pathology)

History of malignancy anywhere (LR+ 14.7 for spinal mets)
Constitutional symptoms: fever, weight loss, night sweats (infection / malignancy)
Night pain that awakens from sleep (tumour until proven otherwise)
Bilateral neurological symptoms (myelopathy, cauda equina)
Bowel/bladder dysfunction with back pain (CES - surgical emergency)
Trauma mechanism (fracture, ligament injury)
Acute swelling / haemarthrosis (ACL, fracture)
Vascular risk factors + claudication distance (PAD vs. neurogenic)
Immunosuppression / IV drug use / recent instrumentation (infection)

Negative History Points (Reassuring / Mechanical Nature)

Young patient, no systemic symptoms
Clear precipitating activity (injury mechanism consistent with diagnosis)
Pain improves with rest
No night pain
No neurological symptoms
Responds to NSAIDS / physiotherapy within 4-6 weeks
Duration < 6 weeks

Key Diagnoses NOT to Miss in Orthopaedics

"Must Not Miss"	Key History Clue
Cauda equina syndrome	Bilateral leg symptoms + bladder/bowel dysfunction
Spinal cord compression (myelopathy)	Bilateral progressive weakness, spasticity, hand clumsiness
Spinal metastases	Night pain + cancer history + age > 50
Spinal epidural abscess	Fever + severe back pain + IV drug use / recent procedure
AAA rupture	Severe back/flank pain + hypotension + elderly male (not positional)
Septic arthritis	Hot joint + fever + inability to weight bear
Pathological fracture	Minimal trauma + osteoporosis / cancer history
DVT with referred knee pain	Calf swelling + risk factors after immobility/surgery
Hip fracture presenting as knee pain	Elderly fall + cannot weight bear
ACL rupture	"Pop" + immediate haemarthrosis + giving way

Sources: Goldman-Cecil Medicine; Tintinalli's Emergency Medicine; Harrison's Principles of Internal Medicine 22E; Miller's Review of Orthopaedics 9E; Campbell's Operative Orthopaedics 15E; S Das Manual on Clinical Surgery 13E; Symptom to Diagnosis 4E; Bradley & Daroff's Neurology in Clinical Practice.

Make a presentation on differential diagnosis algorithms for knee, hip, and back pain

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Running Command

ls /home/daytona/workspace/ 2>/dev/null && mkdir -p /home/daytona/workspace/ortho-ddx-pptx

Writing File

~/ortho-ddx-pptx/create_pptx.js

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// ════════════════════════════════════════════════════════════════════
// SLIDE 2 – OVERVIEW: APPROACH TO MUSCULOSKELETAL PAIN
// ════════════════════════════════════════════════════════════════════
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    { n: "4", title: "INVESTIGATE", detail: "X-ray (weight-bearing)\nMRI (soft tissue / neural)\nBlood tests: ESR, CRP\nBone scan · EMG/NCS" },
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    ["Response to rest", "Improves", "Variable", "No improvement", "No improvement"],
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// ════════════════════════════════════════════════════════════════════
// SLIDE 3 – KNEE PAIN ALGORITHM (PART 1: LOCATION-BASED)
// ════════════════════════════════════════════════════════════════════
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      label: "POSTERIOR",
      color: C.teal,
      dx: 1.5, dy: 1.6, bw: 3.1, bh: 1.3,
      items: [
        "Baker's cyst (popliteal cyst)",
        "Posterior capsule sprain",
        "PCL tear",
        "DVT (exclude!)",
      ],
    },
    {
      dir: "bottom-left",
      label: "DIFFUSE / INTRA-ARTICULAR",
      color: C.orange,
      dx: -4.8, dy: 1.4, bw: 3.6, bh: 1.65,
      items: [
        "Osteoarthritis (commonest)",
        "Rheumatoid arthritis",
        "Crystal arthropathy (gout/pseudogout)",
        "Septic arthritis (EMERGENCY)",
        "Haemarthrosis (ACL rupture, fracture)",
      ],
    },
    {
      dir: "left",
      label: "MEDIAL",
      color: C.teal,
      dx: -4.5, dy: -0.6, bw: 3.5, bh: 1.6,
      items: [
        "Medial meniscus tear",
        "MCL sprain / tear",
        "Pes anserine bursitis",
        "Medial tibial plateau fracture",
        "Medial plica syndrome",
      ],
    },
  ];

  branches.forEach(b => {
    const bx = cx + b.dx;
    const by = cy + b.dy;

    // Arrow from centre to box edge
    const arrowStartX = cx;
    const arrowStartY = cy;
    const arrowEndX = bx + b.bw / 2;
    const arrowEndY = by + b.bh / 2;
    s.addShape(pres.ShapeType.line, {
      x: Math.min(arrowStartX, arrowEndX),
      y: Math.min(arrowStartY, arrowEndY),
      w: Math.abs(arrowEndX - arrowStartX),
      h: Math.abs(arrowEndY - arrowStartY),
      line: { color: C.midGrey, width: 1, endArrowType: "triangle" },
      flipH: arrowStartX > arrowEndX,
      flipV: arrowStartY > arrowEndY,
    });

    // Region header
    s.addShape(pres.ShapeType.roundRect, {
      x: bx, y: by, w: b.bw, h: 0.35,
      fill: { color: b.color }, rectRadius: 0.06,
    });
    s.addText(b.label, {
      x: bx, y: by, w: b.bw, h: 0.35,
      fontSize: 10, bold: true, color: C.white, align: "center", valign: "middle",
      fontFace: "Calibri", margin: 0,
    });
    // Items
    s.addShape(pres.ShapeType.roundRect, {
      x: bx, y: by + 0.35, w: b.bw, h: b.bh - 0.35,
      fill: { color: C.white }, line: { color: b.color, width: 1 }, rectRadius: 0.06,
    });
    const txtItems = b.items.map((t, i) => ({
      text: t,
      options: { bullet: { type: "bullet" }, breakLine: i < b.items.length - 1, fontSize: 9 },
    }));
    s.addText(txtItems, {
      x: bx + 0.1, y: by + 0.4, w: b.bw - 0.2, h: b.bh - 0.48,
      fontFace: "Calibri", color: C.darkText, valign: "top", fontSize: 9,
    });
  });

  // Footnote
  s.addText("* Always examine the HIP — hip pathology (OA, fracture) commonly presents as knee pain  |  Immediate effusion (< 2h) = haemarthrosis (ACL rupture until proven otherwise)", {
    x: 0.35, y: 6.95, w: 12.6, h: 0.35,
    fontSize: 8, color: C.midGrey, fontFace: "Calibri", italic: true,
  });
}

// ════════════════════════════════════════════════════════════════════
// SLIDE 4 – KNEE PAIN DECISION FLOWCHART
// ════════════════════════════════════════════════════════════════════
{
  const s = pres.addSlide();
  s.background = { color: C.offWhite };
  headerStrip(s, "Knee Pain — Clinical Decision Flowchart", "Structured stepwise diagnostic approach");

  // Start node
  flowBox(s, "PATIENT WITH KNEE PAIN", 4.3, 1.35, 4.7, 0.52, C.navy, C.white, 13);
  downArrow(s, 6.65, 1.87, 0.28);

  // Q1
  flowBox(s, "Trauma / acute injury?", 4.8, 2.15, 3.7, 0.45, C.teal, C.white, 11);
  // YES branch
  s.addShape(pres.ShapeType.line, { x: 6.65, y: 2.6, w: 0, h: 0.22, line: { color: C.midGrey, width: 1.5, endArrowType: "triangle" } });
  flowBox(s, "Immediate swelling\n(< 2 hours)?", 5.2, 2.82, 2.9, 0.55, "2471A3", C.white, 10);

  // YES from immediate swelling
  s.addShape(pres.ShapeType.line, { x: 5.2, y: 3.09, w: -0.25, h: 0, line: { color: C.green, width: 1.5, endArrowType: "triangle" } });
  flowBox(s, "YES → Haemarthrosis\n• ACL rupture\n• Osteochondral fracture\n• Patellar dislocation", 2.1, 2.78, 2.8, 0.72, C.orange, C.white, 9);

  // NO from immediate swelling
  s.addShape(pres.ShapeType.line, { x: 8.1, y: 3.09, w: 0.25, h: 0, line: { color: C.midGrey, width: 1.5, endArrowType: "triangle" } });
  flowBox(s, "NO → Delayed swelling\n(12–24 h)\n• Meniscal tear\n• Ligament sprain\n• Contusion", 8.35, 2.78, 2.9, 0.72, C.teal, C.white, 9);

  // Q2 — Trauma NO
  s.addShape(pres.ShapeType.line, { x: 8.5, y: 2.37, w: 0.25, h: 0, line: { color: C.midGrey, width: 1.5, endArrowType: "triangle" } });
  flowBox(s, "NO trauma:\nInflammatory symptoms?\n(fever, warm, erythema, systemic)", 8.75, 2.1, 4.1, 0.6, "2471A3", C.white, 9.5);

  // YES inflammatory
  s.addShape(pres.ShapeType.line, { x: 10.8, y: 2.7, w: 0, h: 0.22, line: { color: C.orange, width: 1.5, endArrowType: "triangle" } });
  flowBox(s, "HOT SWOLLEN JOINT\nSeptic arthritis (EMERGENCY)\nGout / Pseudogout\nReactive arthritis\nRA flare\n⚑ Joint aspiration indicated", 9.2, 2.92, 3.2, 1.05, C.orange, C.white, 9);

  // NO inflammatory → chronic
  s.addShape(pres.ShapeType.line, { x: 4.8, y: 2.37, w: -0.25, h: 0, line: { color: C.midGrey, width: 1.5, endArrowType: "triangle" } });
  flowBox(s, "NO trauma, NO inflammation:\nLocation of pain?", 1.3, 2.1, 3.25, 0.55, "2471A3", C.white, 10);

  // Location branches
  const locs = [
    { label: "Anterior", dx: 0.2,  dx2: 0.2,  diag: "Patellofemoral OA\nPatellar tendinopathy\nBursitis" },
    { label: "Medial",   dx: 1.55, dx2: 1.55, diag: "Medial meniscus tear\nMCL injury\nPes anserine bursitis" },
    { label: "Lateral",  dx: 2.9,  dx2: 2.9,  diag: "Lateral meniscus tear\nIT band syndrome\nLCL injury" },
  ];
  locs.forEach(l => {
    s.addShape(pres.ShapeType.line, { x: 1.3 + l.dx + 0.5, y: 2.65, w: 0, h: 0.25, line: { color: C.midGrey, width: 1.5, endArrowType: "triangle" } });
    flowBox(s, l.label, 0.85 + l.dx, 2.9, 1.1, 0.36, C.green, C.white, 9.5);
    s.addShape(pres.ShapeType.line, { x: 1.4 + l.dx, y: 3.26, w: 0, h: 0.22, line: { color: C.midGrey, width: 1.5, endArrowType: "triangle" } });
    flowBox(s, l.diag, 0.7 + l.dx2, 3.48, 1.45, 0.7, C.white, C.darkText, 8);
    // border
    s.addShape(pres.ShapeType.roundRect, { x: 0.7 + l.dx2, y: 3.48, w: 1.45, h: 0.7, fill: { color: C.white }, line: { color: C.green, width: 1 }, rectRadius: 0.06 });
  });

  // Mechanical symptoms row
  s.addShape(pres.ShapeType.line, { x: 2.92, y: 3.26, w: 0, h: 0.6, line: { color: C.midGrey, width: 1.5 } });
  s.addShape(pres.ShapeType.line, { x: 2.92, y: 3.86, w: 0.6, h: 0, line: { color: C.midGrey, width: 1.5, endArrowType: "triangle" } });
  flowBox(s, "Mechanical symptoms?\n(locking, giving way, click)", 3.52, 3.68, 3.0, 0.52, "2471A3", C.white, 9.5);
  s.addShape(pres.ShapeType.line, { x: 6.52, y: 3.94, w: 0.28, h: 0, line: { color: C.orange, width: 1.5, endArrowType: "triangle" } });
  flowBox(s, "Locking → Meniscal (bucket-handle)\nGiving way → ACL / PF instability\nClick → Meniscal / Plica", 6.8, 3.68, 3.55, 0.52, C.teal, C.white, 9);

  // Neurological / referred
  s.addShape(pres.ShapeType.rect, { x: 0.35, y: 4.55, w: 12.6, h: 0.04, fill: { color: C.lightGrey } });
  s.addText("⚠  Always check: Hip exam (referred pain) · Neurovascular screen (DVT, common peroneal nerve) · BMI & gait for OA workup", {
    x: 0.4, y: 4.65, w: 12.5, h: 0.38,
    fontSize: 9.5, color: C.orange, bold: true, fontFace: "Calibri",
  });

  // Investigation guide
  s.addShape(pres.ShapeType.roundRect, {
    x: 0.35, y: 5.1, w: 12.6, h: 2.15,
    fill: { color: C.white }, line: { color: C.lightGrey, width: 1 }, rectRadius: 0.1,
  });
  s.addText("Investigation Pathway for Knee Pain", {
    x: 0.5, y: 5.12, w: 8, h: 0.32,
    fontSize: 11, bold: true, color: C.navy, fontFace: "Calibri", margin: 0,
  });

  const invCols = [
    { title: "FIRST LINE", color: C.green, items: ["Weight-bearing X-ray (AP, lateral, skyline)", "Inflammatory markers (ESR, CRP, WBC)", "Uric acid (if gout suspected)", "Joint aspiration (hot joint)"] },
    { title: "SECOND LINE", color: C.teal, items: ["MRI knee (meniscus, ligament, cartilage)", "Ultrasound (Baker's cyst, bursitis, tendon)", "DECT (gout tophus)"] },
    { title: "SPECIAL CASES", color: C.orange, items: ["Bone scan (stress fracture, AVN, occult)", "CT (complex fracture, tibial plateau)", "Synovial fluid microscopy (crystals, culture)"] },
  ];

  invCols.forEach((col, i) => {
    const cx2 = 0.45 + i * 4.3;
    s.addShape(pres.ShapeType.roundRect, { x: cx2, y: 5.48, w: 4.1, h: 0.32, fill: { color: col.color }, rectRadius: 0.05 });
    s.addText(col.title, { x: cx2, y: 5.48, w: 4.1, h: 0.32, fontSize: 10, bold: true, color: C.white, align: "center", valign: "middle", fontFace: "Calibri", margin: 0 });
    const buls = col.items.map((t, idx) => ({ text: t, options: { bullet: { type: "bullet" }, breakLine: idx < col.items.length - 1 } }));
    s.addText(buls, { x: cx2 + 0.08, y: 5.82, w: 3.95, h: 1.38, fontSize: 9, color: C.darkText, fontFace: "Calibri", valign: "top" });
  });
}

// ════════════════════════════════════════════════════════════════════
// SLIDE 5 – HIP PAIN ALGORITHM
// ════════════════════════════════════════════════════════════════════
{
  const s = pres.addSlide();
  s.background = { color: C.offWhite };
  headerStrip(s, "Hip Pain — Differential Diagnosis Algorithm", "Location of pain is the primary diagnostic guide");

  // Central node
  flowBox(s, "HIP PAIN", 5.85, 1.55, 1.6, 0.5, C.navy, C.white, 14);

  // 4 primary zones
  const zones = [
    {
      label: "GROIN / ANTERIOR HIP",
      color: C.teal,
      x: 0.3, y: 1.45, w: 4.5, h: 2.35,
      items: [
        { t: "Hip OA (commonest — insidious, elderly)", b: true },
        { t: "Femoral neck fracture (elderly, fall, cannot WB)", b: true },
        { t: "AVN of femoral head (steroids, EtOH, SCD)", b: false },
        { t: "Labral tear (young, athletic, catching)", b: false },
        { t: "Psoas bursitis / tendinopathy", b: false },
        { t: "Hip joint effusion (septic arthritis)", b: false },
        { t: "Femoral stress fracture (young runner)", b: false },
      ],
      arrow: { from: "right", targetX: 5.85, targetY: 1.8 },
    },
    {
      label: "LATERAL HIP / GREATER TROCHANTER",
      color: C.green,
      x: 0.3, y: 4.1, w: 4.5, h: 2.05,
      items: [
        { t: "Trochanteric bursitis / gluteus medius tendinopathy (most common lateral hip pain)", b: false },
        { t: "IT band syndrome", b: false },
        { t: "Snapping hip (coxa saltans)", b: false },
        { t: "L4-L5 referred pain (lateral thigh)", b: false },
      ],
      arrow: null,
    },
    {
      label: "POSTERIOR / BUTTOCK",
      color: C.amber,
      x: 8.5, y: 1.45, w: 4.5, h: 2.1,
      items: [
        { t: "Piriformis syndrome (buttock, sciatica-like)", b: false },
        { t: "SI joint dysfunction / sacroiliitis", b: false },
        { t: "L5-S1 radiculopathy (referred)", b: false },
        { t: "Ischiogluteal bursitis (sitting pain)", b: false },
        { t: "Proximal hamstring tear", b: false },
      ],
      arrow: { from: "left", targetX: 7.45, targetY: 1.8 },
    },
    {
      label: "DIFFUSE / SYSTEMIC",
      color: C.orange,
      x: 8.5, y: 3.85, w: 4.5, h: 2.3,
      items: [
        { t: "Inflammatory arthritis (RA, AS, PsA)", b: false },
        { t: "Crystal arthropathy (rare in hip)", b: false },
        { t: "Septic arthritis (HOT, cannot WB — EMERGENCY)", b: true },
        { t: "Malignancy / bone metastases (night pain, weight loss)", b: true },
        { t: "Paget's disease (elderly, deformity)", b: false },
        { t: "Transient osteoporosis of hip (pregnant, MRI)", b: false },
      ],
      arrow: null,
    },
  ];

  zones.forEach(z => {
    s.addShape(pres.ShapeType.roundRect, {
      x: z.x, y: z.y, w: z.w, h: 0.35,
      fill: { color: z.color }, rectRadius: 0.06,
    });
    s.addText(z.label, {
      x: z.x, y: z.y, w: z.w, h: 0.35,
      fontSize: 9.5, bold: true, color: C.white, align: "center", valign: "middle",
      fontFace: "Calibri", margin: 0,
    });
    s.addShape(pres.ShapeType.roundRect, {
      x: z.x, y: z.y + 0.35, w: z.w, h: z.h - 0.35,
      fill: { color: C.white }, line: { color: z.color, width: 1 }, rectRadius: 0.06,
    });
    const buls = z.items.map((t, i) => ({
      text: t.t,
      options: {
        bullet: { type: "bullet" },
        breakLine: i < z.items.length - 1,
        bold: t.b,
        color: t.b ? C.orange : C.darkText,
      },
    }));
    s.addText(buls, {
      x: z.x + 0.1, y: z.y + 0.4, w: z.w - 0.2, h: z.h - 0.52,
      fontSize: 9, fontFace: "Calibri", valign: "top",
    });
  });

  // Age-based triage box (centre bottom)
  s.addShape(pres.ShapeType.roundRect, {
    x: 4.8, y: 2.25, w: 3.7, h: 3.75,
    fill: { color: "EEF3F8" }, line: { color: C.navy, width: 1.5 }, rectRadius: 0.1,
  });
  s.addText("AGE-BASED TRIAGE", {
    x: 4.8, y: 2.25, w: 3.7, h: 0.38,
    fontSize: 11, bold: true, color: C.navy, align: "center", valign: "middle",
    fontFace: "Calibri", margin: 0,
  });

  const ageGroups = [
    { age: "Child / Adolescent", color: C.teal, diag: "Perthes disease, SCFE, transient synovitis, developmental dysplasia" },
    { age: "Young Adult (20–40)", color: C.green, diag: "Labral tear, AVN (steroids/EtOH), stress fracture, FAI, athletic injury" },
    { age: "Middle Age (40–60)", color: C.amber, diag: "OA (early), trochanteric bursitis, piriformis syndrome, RA" },
    { age: "Elderly (> 60)", color: C.orange, diag: "OA (late), femoral neck fracture, AVN, malignancy, Paget's" },
  ];

  ageGroups.forEach((ag, i) => {
    const ay = 2.7 + i * 0.82;
    s.addShape(pres.ShapeType.roundRect, { x: 4.9, y: ay, w: 3.5, h: 0.3, fill: { color: ag.color }, rectRadius: 0.05 });
    s.addText(ag.age, { x: 4.9, y: ay, w: 3.5, h: 0.3, fontSize: 9.5, bold: true, color: C.white, align: "center", valign: "middle", fontFace: "Calibri", margin: 0 });
    s.addText(ag.diag, { x: 4.95, y: ay + 0.3, w: 3.4, h: 0.48, fontSize: 8, color: C.darkText, fontFace: "Calibri", valign: "top" });
  });

  // footnote
  s.addText("FABER test: hip / SI joint pain  |  FADIR test: FAI / labral tear  |  Trendelenburg: abductor weakness  |  Leg length: measure ASIS → medial malleolus", {
    x: 0.35, y: 6.95, w: 12.6, h: 0.35,
    fontSize: 8, color: C.midGrey, fontFace: "Calibri", italic: true,
  });
}

// ════════════════════════════════════════════════════════════════════
// SLIDE 6 – BACK PAIN ALGORITHM (TRIAGE)
// ════════════════════════════════════════════════════════════════════
{
  const s = pres.addSlide();
  s.background = { color: C.offWhite };
  headerStrip(s, "Back Pain — Triage Algorithm", "First step: Rule out serious pathology before considering mechanical aetiology");

  // Top flow: triage
  flowBox(s, "BACK PAIN", 5.65, 1.38, 2.0, 0.5, C.navy, C.white, 14);
  downArrow(s, 6.65, 1.88, 0.25);

  // Diamond: Red flags?
  s.addShape(pres.ShapeType.rect, {
    x: 5.6, y: 2.13, w: 2.1, h: 0.6,
    fill: { color: C.orange }, line: { color: C.orange, width: 0 },
  });
  s.addText("RED FLAGS\npresent?", {
    x: 5.6, y: 2.13, w: 2.1, h: 0.6,
    fontSize: 10, bold: true, color: C.white, align: "center", valign: "middle",
    fontFace: "Calibri", margin: 0,
  });

  // YES → serious
  s.addShape(pres.ShapeType.line, { x: 7.7, y: 2.43, w: 0.6, h: 0, line: { color: C.orange, width: 2, endArrowType: "triangle" } });
  s.addText("YES", { x: 7.7, y: 2.27, w: 0.6, h: 0.3, fontSize: 9, bold: true, color: C.orange, fontFace: "Calibri", align: "center" });
  flowBox(s, "⚑ SERIOUS PATHOLOGY\n→ Urgent investigation", 8.3, 2.18, 3.2, 0.5, C.orange, C.white, 10);

  // NO → duration?
  s.addShape(pres.ShapeType.line, { x: 6.65, y: 2.73, w: 0, h: 0.25, line: { color: C.midGrey, width: 1.5, endArrowType: "triangle" } });
  s.addText("NO", { x: 6.7, y: 2.73, w: 0.4, h: 0.25, fontSize: 9, bold: true, color: C.green, fontFace: "Calibri" });
  flowBox(s, "Duration of pain?", 5.65, 2.98, 2.0, 0.45, "2471A3", C.white, 11);

  // Three duration branches
  const durs = [
    { label: "< 6 weeks\n(ACUTE)", color: C.green,  x: 1.5,  diag: "Acute muscle strain\nLigament sprain\nAcute disc herniation\nVertebral fracture (trauma)" },
    { label: "6–12 weeks\n(SUBACUTE)", color: C.amber, x: 5.2, diag: "Recovering disc herniation\nFacet syndrome\nSI joint dysfunction\nInitiate active rehabilitation" },
    { label: "> 12 weeks\n(CHRONIC)", color: C.orange, x: 8.9, diag: "Chronic disc disease\nSpinal stenosis\nFacet arthropathy\nChronification / central sensitisation\nPsychosocial factors (yellow flags)" },
  ];

  durs.forEach((d, i) => {
    const mx = d.x + 1.8;
    s.addShape(pres.ShapeType.line, {
      x: Math.min(6.65, mx), y: 3.2,
      w: Math.abs(6.65 - mx), h: 0,
      line: { color: C.midGrey, width: 1 },
    });
    s.addShape(pres.ShapeType.line, { x: mx, y: 3.2, w: 0, h: 0.25, line: { color: C.midGrey, width: 1.5, endArrowType: "triangle" } });
    flowBox(s, d.label, d.x, 3.45, 3.6, 0.5, d.color, C.white, 10);
    s.addShape(pres.ShapeType.roundRect, {
      x: d.x, y: 3.95, w: 3.6, h: 0.95,
      fill: { color: C.white }, line: { color: d.color, width: 1 }, rectRadius: 0.08,
    });
    s.addText(d.diag, {
      x: d.x + 0.1, y: 4.0, w: 3.4, h: 0.88,
      fontSize: 9, color: C.darkText, fontFace: "Calibri", valign: "top",
    });
  });

  // Red flags detailed box
  s.addShape(pres.ShapeType.roundRect, {
    x: 0.35, y: 5.05, w: 5.6, h: 2.22,
    fill: { color: "FFF0EC" }, line: { color: C.orange, width: 1.5 }, rectRadius: 0.1,
  });
  s.addText("🚩  RED FLAGS — Must Rule Out", {
    x: 0.45, y: 5.08, w: 5.4, h: 0.35,
    fontSize: 11, bold: true, color: C.orange, fontFace: "Calibri", margin: 0,
  });
  const rfItems = [
    "Age < 20 or > 50 years",
    "History of malignancy",
    "Unexplained weight loss / fever",
    "Immunosuppression / IV drug use",
    "Bladder or bowel dysfunction (CES!)",
    "Bilateral neurological symptoms",
    "Night pain / unrelenting pain",
    "History of trauma (fracture risk)",
    "Osteoporosis + minor trauma",
    "Duration > 6 weeks without improvement",
  ];
  const rfBuls = rfItems.map((t, i) => ({
    text: t,
    options: { bullet: { type: "bullet" }, breakLine: i < rfItems.length - 1 },
  }));
  s.addText(rfBuls, {
    x: 0.45, y: 5.46, w: 5.3, h: 1.75,
    fontSize: 9, color: C.darkText, fontFace: "Calibri", valign: "top",
  });

  // Serious pathology classification
  s.addShape(pres.ShapeType.roundRect, {
    x: 6.1, y: 5.05, w: 6.85, h: 2.22,
    fill: { color: C.white }, line: { color: C.navy, width: 1 }, rectRadius: 0.1,
  });
  s.addText("Serious Conditions to Exclude", {
    x: 6.2, y: 5.08, w: 6.6, h: 0.35,
    fontSize: 11, bold: true, color: C.navy, fontFace: "Calibri", margin: 0,
  });

  const seriousCols = [
    { title: "NEURAL / SPINAL", items: ["Cauda equina syndrome", "Myelopathy / cord compression", "Epidural abscess / haematoma", "Spinal fracture"] },
    { title: "SYSTEMIC / REFERRED", items: ["Spinal metastases", "Multiple myeloma", "Aortic aneurysm (AAA)", "Pancreatitis / renal colic"] },
  ];
  seriousCols.forEach((col, i) => {
    const sx = 6.2 + i * 3.35;
    s.addShape(pres.ShapeType.roundRect, { x: sx, y: 5.46, w: 3.2, h: 0.3, fill: { color: i === 0 ? C.orange : C.navy }, rectRadius: 0.04 });
    s.addText(col.title, { x: sx, y: 5.46, w: 3.2, h: 0.3, fontSize: 9, bold: true, color: C.white, align: "center", valign: "middle", fontFace: "Calibri", margin: 0 });
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}

// ════════════════════════════════════════════════════════════════════
// SLIDE 7 – BACK PAIN: DETAILED DIAGNOSTIC CATEGORIES
// ════════════════════════════════════════════════════════════════════
{
  const s = pres.addSlide();
  s.background = { color: C.offWhite };
  headerStrip(s, "Back Pain — Diagnostic Categories & Key Features", "Mechanical (90%) vs. Non-mechanical (10%)");

  const cats = [
    {
      title: "DISC HERNIATION (L4–L5, L5–S1)", color: C.teal, x: 0.3, y: 1.42, w: 3.85,
      items: [
        "Shooting / stabbing LBP + radiculopathy",
        "Worse sitting, better lying / standing",
        "L5: pain to dorsum foot / big toe",
        "S1: pain to lateral foot / small toe",
        "Worse with Valsalva / cough / sneeze",
        "+ve SLR (sens. 85–91%; spec. 26–52%)",
        "+ve crossed SLR (spec. 86–90%)",
      ],
    },
    {
      title: "SPINAL STENOSIS", color: C.green, x: 4.35, y: 1.42, w: 3.85,
      items: [
        "Age > 60, bilateral leg pain",
        "Neurogenic claudication",
        "Worse: walking, standing, extension",
        "Better: forward flexion, sitting, cycling",
        "Mimics vascular claudication",
        "Cycling test: can cycle (flexed = relief)",
        "MRI: narrowed canal, ligamentum flavum hypertrophy",
      ],
    },
    {
      title: "CAUDA EQUINA SYNDROME ⚑ EMERGENCY", color: C.orange, x: 8.4, y: 1.42, w: 4.55,
      items: [
        "Bilateral leg weakness / numbness",
        "Saddle anaesthesia (perineum, inner thighs)",
        "Bladder retention / overflow incontinence",
        "Bowel incontinence / reduced anal tone",
        "PVR > 100 mL = overflow incontinence",
        "Cause: large central disc herniation (L4/5 or L5/S1)",
        "→ Emergency MRI + same-day neurosurgery referral",
      ],
    },
    {
      title: "FACET SYNDROME / SPONDYLOSIS", color: C.amber, x: 0.3, y: 4.12, w: 3.85,
      items: [
        "Axial LBP without radiculopathy",
        "Worse with extension / rotation",
        "Localised paraspinal tenderness",
        "Morning stiffness improves with activity",
        "X-ray: facet arthrosis, osteophytes",
        "Facet injection: diagnostic + therapeutic",
      ],
    },
    {
      title: "SI JOINT SYNDROME", color: "6B3E9E", x: 4.35, y: 4.12, w: 3.85,
      items: [
        "Unilateral buttock / posterior thigh pain",
        "FABER test positive",
        "Posterior SI compression positive",
        "Pain radiating to groin",
        "Common in pregnancy",
        "Ankylosing spondylitis: bilateral sacroiliitis",
      ],
    },
    {
      title: "NON-MECHANICAL / SYSTEMIC", color: C.navy, x: 8.4, y: 4.12, w: 4.55,
      items: [
        "Night pain: tumour, infection",
        "Metastases: breast, prostate, lung, kidney, thyroid",
        "Myeloma: lytic lesions (bone scan may miss!)",
        "Discitis/osteomyelitis: fever + localised tenderness",
        "AAA: bilateral flank/back pain, pulsatile mass",
        "→ ESR, CRP, PSA, SPEP, MRI, bone scan",
      ],
    },
  ];

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      x: c.x, y: c.y, w: c.w, h: 0.38,
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      x: c.x, y: c.y, w: c.w, h: 0.38,
      fontSize: 9.5, bold: true, color: C.white, align: "center", valign: "middle",
      fontFace: "Calibri", margin: 0,
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    s.addShape(pres.ShapeType.roundRect, {
      x: c.x, y: c.y + 0.38, w: c.w, h: bh - 0.38,
      fill: { color: C.white }, line: { color: c.color, width: 1 }, rectRadius: 0.06,
    });
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      text: t,
      options: { bullet: { type: "bullet" }, breakLine: i < c.items.length - 1 },
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    s.addText(buls, {
      x: c.x + 0.1, y: c.y + 0.43, w: c.w - 0.2, h: bh - 0.5,
      fontSize: 9, color: C.darkText, fontFace: "Calibri", valign: "top",
    });
  });

  // LR table at bottom
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    x: 0.3, y: 6.72, w: 12.7, h: 0.55,
    fill: { color: "EEF3F8" }, line: { color: C.navy, width: 1 }, rectRadius: 0.06,
  });
  s.addText([
    { text: "Likelihood Ratios for Cancer: ", options: { bold: true } },
    { text: "History of cancer LR+ 14.7  |  Age >50 LR+ 2.7  |  Weight loss LR+ 2.7  |  Failure conservative Rx LR+ 3.0  |  Nocturnal pain LR− 0.17  |  ESR ≥50 LR+ 19.2", options: {} },
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    x: 0.4, y: 6.75, w: 12.5, h: 0.48,
    fontSize: 9, color: C.darkText, fontFace: "Calibri", valign: "middle",
  });
}

// ════════════════════════════════════════════════════════════════════
// SLIDE 8 – NERVE ROOT / DERMATOME REFERENCE
// ════════════════════════════════════════════════════════════════════
{
  const s = pres.addSlide();
  s.background = { color: C.offWhite };
  headerStrip(s, "Lumbar Radiculopathy — Nerve Root Reference Table", "Correlate history, dermatomal pain, motor signs, and reflexes");

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    [
      { text: "Level", options: { bold: true, fill: { color: C.navy }, color: C.white } },
      { text: "Pain Distribution", options: { bold: true, fill: { color: C.navy }, color: C.white } },
      { text: "Sensory Loss", options: { bold: true, fill: { color: C.navy }, color: C.white } },
      { text: "Motor Weakness", options: { bold: true, fill: { color: C.navy }, color: C.white } },
      { text: "Reflex Change", options: { bold: true, fill: { color: C.navy }, color: C.white } },
      { text: "Provocation Test", options: { bold: true, fill: { color: C.navy }, color: C.white } },
    ],
    [
      { text: "L2–L3", options: { bold: true, fill: { color: "EEF3F8" } } },
      "Anterior thigh to knee",
      "Anterior / medial thigh",
      "Hip flexion, knee extension (quadriceps)",
      "Knee jerk may be reduced",
      "+ve Femoral stretch test",
    ],
    [
      { text: "L4", options: { bold: true, fill: { color: "EEF3F8" } } },
      "Medial leg to medial foot / great toe",
      "Medial lower leg, dorsum foot",
      "Tibialis anterior (dorsiflexion weakness)",
      "Knee jerk reduced",
      "+ve SLR, Femoral stretch",
    ],
    [
      { text: "L5", options: { bold: true, fill: { color: "EEF3F8" } } },
      "Lateral leg → dorsum foot → big toe",
      "Dorsum of foot, 1st web space",
      "EHL weakness (cannot extend big toe), foot drop risk",
      "Usually preserved",
      "+ve SLR (30–70°)",
    ],
    [
      { text: "S1", options: { bold: true, fill: { color: "EEF3F8" } } },
      "Posterior thigh/leg → lateral foot → small toe",
      "Lateral foot, plantar",
      "Peroneus longus/brevis (eversion), gastrocnemius",
      "Ankle jerk reduced/absent",
      "+ve SLR, +ve crossed SLR",
    ],
    [
      { text: "S2–S4\n(Cauda equina)", options: { bold: true, fill: { color: "FFF0EC" }, color: C.orange } },
      "Bilateral legs, perineum, saddle area",
      "Saddle anaesthesia",
      "Bilateral leg weakness, bladder/bowel dysfunction",
      { text: "Multiple reflexes absent", options: { color: C.orange, bold: true } },
      { text: "EMERGENCY — immediate MRI", options: { color: C.orange, bold: true } },
    ],
  ];

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    rowH: 0.58,
    align: "center",
    valign: "middle",
    autoPage: false,
  });

  // SLR accuracy box
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    x: 0.3, y: 5.72, w: 6.0, h: 1.55,
    fill: { color: C.white }, line: { color: C.teal, width: 1.5 }, rectRadius: 0.1,
  });
  s.addText("Straight Leg Raise (SLR) — Accuracy", {
    x: 0.4, y: 5.75, w: 5.8, h: 0.32,
    fontSize: 11, bold: true, color: C.teal, fontFace: "Calibri", margin: 0,
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  s.addText([
    { text: "• SLR (ipsilateral): ", options: { bold: true } },
    { text: "Sensitivity 85–91%, Specificity 26–52% for disc herniation / sciatica\n", options: {} },
    { text: "• Crossed SLR: ", options: { bold: true } },
    { text: "Sensitivity 23–34%, Specificity 86–90% — high specificity for disc extrusion\n", options: {} },
    { text: "• Femoral stretch test: ", options: { bold: true } },
    { text: "L2, L3, L4 nerve roots (anterior thigh pain when knee flexed prone)", options: {} },
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    x: 0.4, y: 6.1, w: 5.8, h: 1.1,
    fontSize: 9.5, color: C.darkText, fontFace: "Calibri", valign: "top",
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    x: 6.6, y: 5.72, w: 6.4, h: 1.55,
    fill: { color: C.white }, line: { color: C.navy, width: 1.5 }, rectRadius: 0.1,
  });
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    fontSize: 11, bold: true, color: C.navy, fontFace: "Calibri", margin: 0,
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  const painFeats = [
    "Worse sitting + better lying → Disc herniation",
    "Worse walking + better flexion → Spinal stenosis",
    "Night pain waking from sleep → Tumour or infection",
    "Valsalva-provoked pain → Disc herniation",
    "Unrelenting + positional → AAA / systemic cause",
  ];
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    text: t,
    options: { bullet: { type: "bullet" }, breakLine: i < painFeats.length - 1 },
  }));
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    x: 6.7, y: 6.1, w: 6.2, h: 1.1,
    fontSize: 9.5, color: C.darkText, fontFace: "Calibri", valign: "top",
  });
}

// ════════════════════════════════════════════════════════════════════
// SLIDE 9 – YELLOW FLAGS & SUMMARY
// ════════════════════════════════════════════════════════════════════
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  const s = pres.addSlide();
  s.background = { color: C.offWhite };
  headerStrip(s, "Yellow Flags, Investigation Summary & Must-Not-Miss Diagnoses", "Psychosocial factors and surgical/urgent conditions");

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    fontSize: 11, bold: true, color: C.amber, fontFace: "Calibri", margin: 0,
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    "Belief pain = disabling / catastrophic",
    "Fear-avoidance of activity",
    "Depression / anxiety / stress",
    "Poor social/occupational support",
    "Passive coping strategy",
    "Previous compensation / litigation",
    "Prolonged sick leave",
  ];
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      { text: "Action", options: { bold: true, fill: { color: C.navy }, color: C.white } },
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    [{ text: "Cauda Equina Syndrome", options: { bold: true, color: C.orange } }, "Bilateral legs + bladder/bowel dysfunction + saddle anaesthesia", { text: "EMERGENCY MRI → neurosurgery same day", options: { bold: true, color: C.orange } }],
    ["Cord compression / myelopathy", "Bilateral progressive weakness, spasticity, hand clumsiness", "Urgent MRI whole spine"],
    ["Spinal metastases", "Night pain + cancer history + age > 50 + weight loss", "MRI ± bone scan, oncology referral"],
    ["Epidural abscess", "Fever + severe back pain + IVDU / recent procedure / immunocompromised", "MRI + IV antibiotics, urgent drainage"],
    ["AAA rupture", "Elderly male + severe back/flank pain + hypotension + pulsatile mass", "Emergency vascular surgery"],
    ["Septic arthritis (knee/hip)", "Hot joint + fever + inability to weight bear + raised WBC/CRP", "Joint aspiration + IV antibiotics"],
    ["Pathological fracture", "Minimal trauma + osteoporosis / malignancy history", "X-ray/CT + bone density + oncology"],
    ["Hip fracture → knee pain", "Elderly fall + cannot weight bear + hip exam positive", "X-ray hip ± CT"],
    ["ACL rupture → haemarthrosis", "'Pop' + immediate large effusion + giving way", "MRI knee + orthopaedic referral"],
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  const invPrinciples = [
    "No red flags + < 6 weeks: conservative Rx, no imaging needed",
    "X-ray: fracture, alignment, deformity",
    "MRI: soft tissue, neural, disc (false positive very common!)",
    "Blood: ESR, CRP, WBC, CMP, ALP, PSA, SPEP",
    "ESR ≥50 LR+ 19.2 for cancer-related LBP",
    "Correlate imaging with clinical findings always",
  ];
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  s.addText("Sources: Harrison's 22E · Goldman-Cecil Medicine · Tintinalli's EM · Campbell's Operative Orthopaedics 15E · Miller's Review of Orthopaedics 9E · S Das Clinical Surgery 13E · Symptom to Diagnosis 4E", {
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// ════════════════════════════════════════════════════════════════════
// WRITE FILE
// ════════════════════════════════════════════════════════════════════
pres.writeFile({ fileName: "/home/daytona/workspace/ortho-ddx-pptx/Orthopaedic_DDx_Algorithms.pptx" })
  .then(() => console.log("DONE: Orthopaedic_DDx_Algorithms.pptx written successfully"))
  .catch(err => { console.error("ERROR:", err); process.exit(1); });

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