DiagnosticTree/Chest
{
"tree_id": "chest", "region": "Chest Pain — Myofascial", "start": "rf-screen",
"redflags": {
"instruction": "Screen ALL THREE groups before proceeding. If ANY feature within a group is present, act on that group's action immediately — do not continue to the myofascial algorithm.",
"cardiac": {
"id": "rf-cardiac",
"label": "Cardiac & Vascular Emergencies",
"screen_question": "Are ANY of the following present?",
"conditions": [
{
"label": "Acute Coronary Syndrome (MI / Unstable Angina / STEMI)",
"features": "Crushing, pressure, or squeezing chest pain; radiation to left arm, jaw, or back; diaphoresis, nausea, or vomiting; pain at rest or with minimal exertion; known CAD with new or changing pattern"
},
{
"label": "Stable Angina — new presentation or decompensating",
"features": "Predictable exertional chest tightness relieved by rest or GTN, now occurring with less exertion or lasting longer than usual"
},
{
"label": "Cardiac Arrhythmia — haemodynamically significant",
"features": "Palpitations with chest pain, presyncope, syncope, or breathlessness; irregular or very rapid pulse; known arrhythmia with new chest symptoms. Note: a pectoralis major TrP (right side, 5th–6th interspace) can trigger ectopic supraventricular rhythm — cardiac investigations are still required first."
},
{
"label": "Aortic Dissection",
"features": "Sudden tearing or ripping chest or back pain; hypertension or Marfan features; pulse or BP difference between arms"
},
{
"label": "Dilating / Ruptured Aortic Aneurysm",
"features": "Severe tearing back or abdominal pain; pulsatile abdominal mass; haemodynamic compromise"
}
],
"action": "Call emergency services immediately. Do not proceed with myofascial assessment. Note: myocardial infarction activates satellite TrPs in the pectoral muscles that persist after cardiac recovery — these can be assessed once cardiac status is confirmed stable.",
"clinical_note": "Relief of chest pain by vapocoolant spray or local injection does NOT exclude cardiac origin. A definitive diagnosis of active myofascial TrPs does NOT exclude coexisting cardiac disease. Cardiac status must be established in every patient with chest pain."
},
"respiratory": {
"id": "rf-respiratory",
"label": "Respiratory & Pulmonary Emergencies",
"screen_question": "Are ANY of the following present?",
"conditions": [
{
"label": "Pulmonary Embolism",
"features": "Sudden-onset pleuritic chest pain (sharp, worse on inhalation); unexplained breathlessness or hypoxia; haemoptysis; recent immobility, surgery, long-haul travel, or known thrombophilia; tachycardia"
},
{
"label": "Tension Pneumothorax",
"features": "Sudden-onset severe unilateral chest pain with rapidly progressive breathlessness; tracheal deviation; absent breath sounds on the affected side; haemodynamic compromise. Distinguish from simple pneumothorax (tall thin young person, or post-trauma) which is urgent but not immediately life-threatening."
},
{
"label": "Pneumonia with Pleurisy",
"features": "Fever, productive cough, and pleuritic chest pain (sharp, worse on breathing); reduced breath sounds or bronchial breathing; systemic illness. Note: intercostal TrPs commonly develop secondary to pneumonia — TrP involvement does not exclude active infection."
},
{
"label": "Neoplasm — Primary or Metastatic",
"features": "Persistent unilateral chest pain not responding to myofascial treatment; unexplained weight loss; haemoptysis; smoking history; known malignancy elsewhere"
},
{
"label": "Tuberculosis",
"features": "Persistent cough (>3 weeks), haemoptysis, night sweats, weight loss, fever; contact with TB or travel to endemic region; immunocompromised patient"
}
],
"action": "Tension pneumothorax: call emergency services immediately. PE: call emergency services immediately. All others: urgent same-day GP referral for chest X-ray and appropriate investigation. Do not proceed with myofascial treatment until serious respiratory pathology is excluded.",
"clinical_note": "Intrathoracic lesions can activate intercostal TrPs which may partially respond to treatment, creating false reassurance. Failure of intercostal TrPs to resolve with appropriate treatment is an indication for imaging."
},
"gastrointestinal": {
"id": "rf-gi",
"label": "Gastrointestinal Emergencies",
"screen_question": "Are ANY of the following present?",
"conditions": [
{
"label": "Oesophageal Perforation (Boerhaave Syndrome)",
"features": "Sudden severe chest or upper abdominal pain immediately following forceful vomiting or retching; subcutaneous emphysema in the neck; rapidly deteriorating systemic state. This is immediately life-threatening."
},
{
"label": "Acute Pancreatitis",
"features": "Severe epigastric or left upper quadrant pain radiating to the back; worse lying flat, relieved leaning forward; nausea and vomiting; history of gallstones or alcohol use; elevated amylase/lipase. Note: external oblique and upper abdominal TrPs can refer epigastric pain that mimics pancreatitis — but the severity of systemic illness distinguishes acute pancreatitis."
}
],
"action": "Oesophageal perforation: call emergency services immediately — surgical emergency. Acute pancreatitis: same-day emergency hospital referral. Do not proceed with myofascial assessment until GI pathology is excluded.",
"clinical_note": "Abdominal wall TrPs (external oblique costal attachment) refer epigastric pain described as heartburn or burning — the Abdominal Tension Test (pain increases when abdominal muscles are tensed) confirms a wall source and distinguishes from visceral GI pathology."
}
},
"nodes": {
"rf-screen": {
"type": "gate",
"question": "Have all three red flag groups — Cardiac, Respiratory, and Gastrointestinal — been screened and excluded by appropriate clinical assessment?",
"clinical_rationale": "All three groups must be cleared before proceeding. If any feature within any group is present, act on that group's action immediately. Relief of chest pain by local treatment does NOT exclude serious pathology.",
"yes": "rom-1",
"no": "refer-cardiac"
},
"rom-1": {
"type": "rom",
"question": "Is the chest pain worsened by deep inhalation, coughing, or sneezing?",
"movement": "Deep inhalation / cough / sneeze",
"direction": "aggravating",
"muscles_implicated": ["Intercostal Muscles", "Diaphragm (peripheral costal fibres)"],
"muscles_excluded": ["Pectoralis Major", "Pectoralis Minor", "SCM", "Subclavius"],
"clinical_rationale": "Pain from deep inhalation, coughing, or sneezing is the cardinal feature of intercostal TrPs. Diaphragmatic TrPs are specifically worsened at full EXHALATION, not inhalation — this question branches those two apart.",
"yes": "rom-2",
"no": "rom-3"
},
"rom-2": {
"type": "rom",
"question": "Is the chest pain most severe — or maximally provoked — at the END of a full exhalation (when the lungs are emptied) rather than at the peak of inhalation?",
"movement": "Full exhalation — end range",
"direction": "aggravating",
"muscles_implicated": ["Diaphragm (peripheral costal fibres)"],
"muscles_excluded": ["Intercostal Muscles"],
"clinical_rationale": "Diaphragmatic TrP pain peaks at end of full exhalation when diaphragm fibres are maximally stretched. Intercostal TrP pain peaks at full inhalation when interspaces are maximally opened. Both may be painful with deep breathing — this question identifies the maximum provocation point.",
"yes": "rom-2b",
"no": "result-intercostal"
},
"rom-2b": {
"type": "rom",
"question": "Is there also pain referred to the upper border of the ipsilateral shoulder (anterior border of the upper trapezius, midway between acromion and neck base)?",
"movement": "Referred shoulder pain screen",
"direction": "present",
"muscles_implicated": ["Diaphragm (central dome — phrenic referral)"],
"muscles_excluded": ["Diaphragm (costal fibres only)"],
"clinical_rationale": "Central dome diaphragmatic TrP referral via the phrenic nerve (C3–C5) produces sharply localised pain to the ipsilateral shoulder top. Peripheral costal fibre referral stays at the costal margin. This distinguishes central dome from peripheral TrP involvement, though both may coexist.",
"yes": "result-diaphragm-central",
"no": "result-diaphragm-costal"
},
"rom-3": {
"type": "rom",
"question": "Is the chest pain aggravated by arm movement — specifically reaching forward, lifting, or crossing the arm across the chest?",
"movement": "Arm elevation / adduction / reaching forward",
"direction": "aggravating",
"muscles_implicated": ["Pectoralis Major", "Pectoralis Minor", "Subclavius"],
"muscles_excluded": ["Intercostal Muscles", "Diaphragm", "SCM", "Iliocostalis Cervicis"],
"yes": "rom-4",
"no": "rom-7"
},
"rom-4": {
"type": "rom",
"question": "Is the chest pain located in the anterior chest — precordium, sternal region, or anterior pectoral area — rather than in the lateral chest wall or rib interspaces?",
"movement": "Pain location screen",
"direction": "present",
"muscles_implicated": ["Pectoralis Major", "Pectoralis Minor"],
"muscles_excluded": ["Intercostal Muscles"],
"yes": "symptom-1",
"no": "result-intercostal"
},
"rom-7": {
"type": "rom",
"question": "Is the chest pain associated with restricted thoracic rotation — i.e. turning the trunk to one side is painful or limited?",
"movement": "Thoracic rotation",
"direction": "aggravating",
"muscles_implicated": ["Intercostal Muscles"],
"muscles_excluded": ["Pectoralis Major", "Pectoralis Minor", "Diaphragm", "SCM"],
"clinical_rationale": "Restricted thoracic rotation is a cardinal sign of intercostal TrP involvement. The intercostals are the primary thoracic rotators and their TrPs reliably restrict this motion.",
"yes": "result-intercostal",
"no": "rom-8"
},
"rom-8": {
"type": "rom",
"question": "Is the pain aggravated by neck movement — specifically neck rotation, lateral flexion, or sustained forward head posture?",
"movement": "Neck rotation / sustained posture",
"direction": "aggravating",
"muscles_implicated": ["SCM (sternal division)", "Iliocostalis Cervicis"],
"muscles_excluded": ["Pectoralis Major", "Pectoralis Minor", "Intercostal Muscles"],
"yes": "symptom-3",
"no": "exam-pec-major-1"
},
"symptom-1": {
"type": "symptom",
"question": "Does the patient report breast tenderness, nipple hypersensitivity, or intolerance to clothing over the chest?",
"symptom_name": "Breast / nipple referred tenderness",
"muscles_implicated": ["Pectoralis Major (costal and abdominal border TrPs)"],
"muscles_excluded": ["Pectoralis Minor", "Subclavius"],
"clinical_rationale": "Breast tenderness with nipple hypersensitivity and intolerance to clothing is the pathognomonic referred symptom of TrPs in the lateral free margin (costal and abdominal sections) of the pectoralis major. This feature is NOT produced by pectoralis minor or subclavius TrPs.",
"yes": "result-pec-major-costal",
"no": "symptom-2"
},
"symptom-2": {
"type": "symptom",
"question": "Does the patient report arm pain extending down the RADIAL side of the forearm to the thumb, index, and middle fingers — with the shoulder front also painful — but skipping the elbow and wrist?",
"symptom_name": "Radial forearm / thumb / index finger pain",
"muscles_implicated": ["Subclavius"],
"muscles_excluded": ["Pectoralis Major (sternal sections)", "Pectoralis Minor"],
"clinical_rationale": "The subclavius produces a pathognomonic skip pattern: anterior shoulder → radial forearm → radial hand (thumb, index, middle fingers), skipping the elbow and wrist. This is distinct from the ulnar distribution of pectoralis minor entrapment and from the medial epicondyle accent of pectoralis major sternal TrPs.",
"yes": "exam-subclavius-1",
"no": "symptom-2b"
},
"symptom-2b": {
"type": "symptom",
"question": "Does the patient report arm pain extending down the ULNAR side of the forearm and hand, accenting the last two to three fingers — with anterior chest and precordial pain?",
"symptom_name": "Ulnar forearm / medial epicondyle / ulnar digit pain with precordial pain",
"muscles_implicated": ["Pectoralis Major (intermediate sternal section)", "Pectoralis Minor"],
"muscles_excluded": ["Subclavius"],
"clinical_rationale": "The pectoralis major intermediate sternal TrPs refer intense precordial pain (left side mimics cardiac ischaemia) with arm pain accenting the medial epicondyle and extending to the ulnar digits. Pectoralis minor refers along the ulnar forearm to the last three fingers. Both patterns are distinct from the radial distribution of the subclavius.",
"yes": "exam-pec-minor-1",
"no": "exam-pec-major-1"
},
"symptom-3": {
"type": "symptom",
"question": "Is there also a dry, tingling cough — not explained by respiratory illness — or the sensation of a sore throat without pharyngeal infection?",
"symptom_name": "Dry tingling cough / sore throat",
"muscles_implicated": ["SCM (sternal division)"],
"muscles_excluded": ["Iliocostalis Cervicis"],
"clinical_rationale": "A dry tingling cough TrP and referred sore throat (pharyngeal pain on swallowing that resolves with SCM pincer compression) are pathognomonic features of the SCM sternal division. These features are not produced by the iliocostalis cervicis.",
"yes": "exam-scm-1",
"no": "exam-iliocostalis-cerv-1"
},
"exam-scm-1": {
"type": "examination",
"question": "Does pincer palpation of the SCM sternal division reproduce anterior chest pain or the sternal region pain — AND does pincer compression of the muscle relieve the sore throat or cough when present?",
"exam_type": "palpation",
"landmark": "Sternal division: pincer palpation along full muscle belly from mastoid to sternal attachment. Grasp the entire sternal head between thumb and forefinger.",
"positive_finding": "Reproduces anterior chest or sternal pain; OR compression relieves sore throat / cough",
"clinical_rationale": "The SCM sternal division refers pain downward to the upper sternal region. The sore throat / cough confirmation test (SCM Compression Test) is pathognomonic — pharyngeal pain resolves with pincer compression of the muscle.",
"muscles_implicated": ["SCM (sternal division)"],
"yes": "result-scm-sternal",
"no": "exam-iliocostalis-cerv-1"
},
"exam-iliocostalis-cerv-1": {
"type": "examination",
"question": "Does flat palpation of the upper thoracic paraspinal region — in the groove lateral to the spinous processes at C7–T4 — reproduce the chest pain or refer pain upward to the posterior neck?",
"exam_type": "palpation",
"landmark": "Lateral column of erector spinae at C7–T4 level, 2–4 cm lateral to the spinous processes. Patient sidelying, knees drawn toward chest to relax paraspinal muscles.",
"positive_finding": "Reproduces chest wall pain or refers pain upward to posterior neck / interscapular area",
"muscles_implicated": ["Iliocostalis Cervicis"],
"yes": "result-iliocostalis-cerv",
"no": "exam-pec-major-1"
},
"exam-pec-major-1": {
"type": "examination",
"question": "Does flat or pincer palpation of the pectoral muscle — with the arm abducted to approximately 90° — reproduce the patient's chest pain or precordial symptoms?",
"exam_type": "palpation",
"landmark": "Clavicular section: flat palpation inferior to clavicle. Sternal section: pincer palpation of the muscle belly with arm abducted ~90°. Costal section: pincer palpation of lateral free margin.",
"positive_finding": "Reproduces familiar chest pain, precordial pain, or arm symptoms",
"muscles_implicated": ["Pectoralis Major"],
"yes": "exam-pec-minor-1",
"no": "exam-ext-oblique-1"
},
"exam-pec-minor-1": {
"type": "examination",
"question": "Does deep palpation of the axilla — reaching the thumb under the lateral edge of the pectoralis major to contact the pectoralis minor directly — reproduce chest or arm symptoms?",
"exam_type": "palpation",
"landmark": "Pincer palpation in the axilla: thumb under the lateral edge of pectoralis major, contacting pectoralis minor against the chest wall. Arm in slight adduction and medial rotation to slacken pectoralis major.",
"positive_finding": "Reproduces anterior chest pain, anterior deltoid pain, or ulnar forearm/finger symptoms",
"muscles_implicated": ["Pectoralis Minor"],
"clinical_rationale": "Pectoralis major is almost always also active when pectoralis minor TrPs are found. Examine pectoralis major first; if positive, both muscles are likely involved.",
"yes": "result-pec-both",
"no": "result-pec-major-only"
},
"exam-subclavius-1": {
"type": "examination",
"question": "Does deep palpation beneath the medial third of the clavicle — with the arm in adduction and medial rotation to relax the overlying pectoralis major — reproduce the radial arm pain?",
"exam_type": "palpation",
"landmark": "Roll thumb under the clavicle at the lateral portion of the medial third. Arm in adduction and medial rotation. Distinguish central TrP tenderness (near midclavicle) from attachment TrP tenderness (lateral to the costoclavicular joint).",
"positive_finding": "Reproduces radial forearm pain or thumb / index finger pain",
"muscles_implicated": ["Subclavius"],
"yes": "result-subclavius",
"no": "exam-pec-major-1"
},
"exam-ext-oblique-1": {
"type": "examination",
"question": "Is the chest pain actually located in the epigastric region or lower anterior chest wall — felt as \"heartburn\" — with a TrP tender point palpable along the lower border of the rib cage or along the costal attachment?",
"exam_type": "palpation",
"landmark": "Flat palpation along the lower border of the rib cage (costal attachment) and the line of attachment to the iliac crest. Abdominal Tension Test: compress the sensitive area, then ask the patient to raise both heels — if pain INCREASES the source is the abdominal wall, not visceral.",
"positive_finding": "Palpable TrP along costal margin reproduces epigastric / lower chest burning; Abdominal Tension Test positive",
"muscles_implicated": ["External Oblique (upper attachment TrPs — costal / subcostal)"],
"yes": "result-ext-oblique",
"no": "result-overlap"
},
"result-intercostal": {
"type": "result",
"diagnosis": "Intercostal Muscle Trigger Point",
"confidence": "high",
"wiki_page": "Muscle:Intercostal_Muscles",
"chapter_ref": "Travell & Simons Vol.2 — Ch.45 Intercostal Muscles",
"notes": "Pain along a rib interspace, worsened by deep inhalation / cough / sneeze, and associated with restricted thoracic rotation. Narrowing of the affected rib interspace is visible on inspection. Pain is aching and localised to the interspace; more posteriorly located TrPs refer more anteriorly.",
"key_distinguishing_features": [
"Pain worsened at PEAK INHALATION — differentiates from diaphragmatic TrPs (worst at full exhalation)",
"Thoracic rotation restricted toward the painful side — cardinal and consistent sign",
"Rib interspace narrowing visible on inspection",
"Patient cannot raise the arm fully on the affected side without pain (opens interspaces)"
],
"treatment_hint": "Spray and stretch, postisometric relaxation with coordinated respiration. Correct paradoxical breathing. Control chronic cough. Avoid chest binders.",
"less_likely": [
{ "muscle": "Diaphragm", "reason": "Pain worst at peak inhalation, not full exhalation" },
{ "muscle": "Pectoralis Major", "reason": "Pain is in rib interspace, not anterior pectoral / precordial region; not aggravated by arm movement" },
{ "muscle": "SCM", "reason": "Thoracic rotation restricted — not neck rotation" }
]
},
"result-diaphragm-central": {
"type": "result",
"diagnosis": "Diaphragm Trigger Point — Central Dome (Phrenic Referral)",
"confidence": "high",
"wiki_page": "Muscle:Diaphragm",
"chapter_ref": "Travell & Simons Vol.2 — Ch.45 Diaphragm",
"notes": "Central dome TrPs produce sharply localised referred pain to the upper border of the ipsilateral shoulder (anterior border of upper trapezius, midway between acromion and neck base) — mediated via the phrenic nerve (C3–C5). This is the same pathway as pain from subphrenic irritation of any cause.",
"key_distinguishing_features": [
"Pain maximally provoked at END of full exhalation — when diaphragm fibres are most stretched",
"Shoulder pain at ipsilateral shoulder top (phrenic referral) — sharply localised",
"Inaccessible to direct palpation — diagnosis based on respiratory motion testing and indirect release response"
],
"treatment_hint": "Indirect manual release under the lower ribs during exhalation. Gravity-assisted stretch. Correct paradoxical breathing. Control chronic cough.",
"less_likely": [
{ "muscle": "Intercostal Muscles", "reason": "Pain worst at full exhalation, not inhalation; shoulder referral present" },
{ "muscle": "Pectoralis Major", "reason": "Pain provoked by respiratory motion, not arm movement" }
]
},
"result-diaphragm-costal": {
"type": "result",
"diagnosis": "Diaphragm Trigger Point — Peripheral Costal Fibres (Intercostal Referral)",
"confidence": "high",
"wiki_page": "Muscle:Diaphragm",
"chapter_ref": "Travell & Simons Vol.2 — Ch.45 Diaphragm",
"notes": "Peripheral costal fibre TrPs produce diffuse aching pain at the adjacent costal margin. No shoulder referral. The stitch-in-the-side during vigorous exercise is a characteristic presentation. The diaphragm is inaccessible to direct palpation — TrP at the costal attachment may be the only reachable point.",
"key_distinguishing_features": [
"Pain maximally provoked at END of full exhalation",
"Pain at costal margin / lower chest wall — diffuse aching",
"No shoulder referral (distinguishes from central dome TrPs)",
"Exercise-related stitch in the side — characteristic"
],
"treatment_hint": "Indirect manual release under the lower ribs. Self-release technique: fingers hooked under lower ribs during slow exhalation. Correct paradoxical breathing.",
"less_likely": [
{ "muscle": "Intercostal Muscles", "reason": "Pain worst at full exhalation, not inhalation" },
{ "muscle": "External Oblique", "reason": "Pain provoked by respiration and worst at exhalation; Abdominal Tension Test likely negative" }
]
},
"result-pec-major-costal": {
"type": "result",
"diagnosis": "Pectoralis Major Trigger Point — Costal / Abdominal Border",
"confidence": "high",
"wiki_page": "Muscle:Pectoralis_Major",
"chapter_ref": "Travell & Simons Vol.1 — Ch.42 Pectoralis Major",
"notes": "TrPs in the lateral free margin (costal and abdominal sections) refer breast tenderness with hypersensitivity of the nipple, intolerance to clothing, and sometimes breast pain. A sensation of breast congestion and slight breast enlargement (oedema from lymphatic entrapment) may be described. This pattern is pathognomonic — no other chest muscle produces nipple hypersensitivity.",
"key_distinguishing_features": [
"Breast tenderness with nipple hypersensitivity and intolerance to clothing — pathognomonic",
"Breast may feel slightly enlarged and doughy — lymphatic entrapment by taut pectoral fibres",
"TrP in the lateral free margin of the pectoralis major — pincer palpation required",
"Round-shouldered posture almost invariably present"
],
"treatment_hint": "Pincer palpation and spray-and-stretch of the costal section: arm flexed at shoulder while held in lateral rotation, spray directed downward over the passively stretched fibres. Correct round-shouldered posture. In-doorway stretch exercise.",
"less_likely": [
{ "muscle": "Pectoralis Minor", "reason": "Does not produce nipple hypersensitivity or breast tenderness — these are specific to pectoralis major costal border TrPs" },
{ "muscle": "Intercostal Muscles", "reason": "Breast and nipple referral not a feature of intercostal TrPs" }
]
},
"result-pec-both": {
"type": "result",
"diagnosis": "Pectoralis Major AND Pectoralis Minor Trigger Points",
"confidence": "high",
"wiki_page": "Muscle:Pectoralis_Major",
"wiki_page_2": "Muscle:Pectoralis_Minor",
"chapter_ref": "Travell & Simons Vol.1 — Ch.42 and Ch.43",
"notes": "Active TrPs in the pectoralis minor are almost never found without coexisting active TrPs in the pectoralis major. The pectoralis minor refers pain over the anterior deltoid and along the ulnar forearm to the last three fingers; the sternal sections of the pectoralis major refer intense precordial pain with medial epicondyle accent. Pectoralis minor tautness may entrap the brachial plexus and axillary artery (Wright manoeuvre positive).",
"key_distinguishing_features": [
"Pectoralis minor: forward (rounded) shoulder with the coracoid pulled anteriorly and inferiorly — elevated shoulder visible when patient is supine",
"Pectoralis minor: restricted full arm abduction with a sense of the ribs being pulled at the end of range",
"Both muscles: precordial pain mimicking cardiac ischaemia",
"Pectoralis minor: ulnar forearm and last three finger symptoms — confirms minor involvement over major alone"
],
"treatment_hint": "Inactivate pectoralis major TrPs FIRST before treating pectoralis minor. Manual release of pectoralis minor with prespray technique. Strengthen lower trapezius. Correct round-shouldered posture.",
"less_likely": [
{ "muscle": "Subclavius", "reason": "Ulnar not radial distribution; pectoralis minor examination positive" },
{ "muscle": "Intercostal Muscles", "reason": "Pain not worsened by deep inhalation or thoracic rotation" }
]
},
"result-pec-major-only": {
"type": "result",
"diagnosis": "Pectoralis Major Trigger Point",
"confidence": "high",
"wiki_page": "Muscle:Pectoralis_Major",
"chapter_ref": "Travell & Simons Vol.1 — Ch.42 Pectoralis Major",
"notes": "The pectoralis major has five functionally distinct TrP zones. The intermediate sternal section TrPs produce intense precordial pain (left side mimics MI) with arm pain accenting the medial epicondyle and extending to the ulnar digits. The clavicular section TrPs refer to the anterior deltoid only. The medial sternal TrPs refer locally over the sternum without crossing the midline.",
"key_distinguishing_features": [
"Wide day-to-day variability in chest pain with activity — distinguishes from the consistent exercise pattern of true angina",
"Precordial pain (left-sided intermediate sternal TrPs) mimics cardiac ischaemia",
"Arm pain from intermediate sternal TrPs accents the MEDIAL EPICONDYLE — not the radial forearm (subclavius pattern)",
"Cardiac arrhythmia TrP (right side, fifth-sixth rib space, midway between sternal border and nipple line) — produces ectopic cardiac rhythm WITHOUT pain"
],
"treatment_hint": "Spray and stretch with the arm abducted to 90° for sternal section. Correct round-shouldered posture. In-doorway stretch exercise. Arrhythmia TrP: treat sternal division TrPs first, then address arrhythmia TrP with pressure release.",
"less_likely": [
{ "muscle": "Pectoralis Minor", "reason": "Pectoralis minor examination negative" },
{ "muscle": "Subclavius", "reason": "Medial epicondyle accent and ulnar distribution — not radial / thumb distribution" }
]
},
"result-subclavius": {
"type": "result",
"diagnosis": "Subclavius Trigger Point",
"confidence": "high",
"wiki_page": "Muscle:Subclavius",
"chapter_ref": "Travell & Simons Vol.1 — Ch.42 Subclavius (within Pectoralis Major chapter)",
"notes": "The pathognomonic skip pattern of the subclavius is: anterior shoulder → radial side of forearm → skipping elbow and wrist → radial hand (thumb, index, middle fingers). TrPs draw the clavicle down toward the subclavian artery and vein, contributing to vascular thoracic outlet syndrome — check for radial pulse reduction with arm abduction.",
"key_distinguishing_features": [
"Skip pattern: anterior shoulder → radial forearm (skipping elbow and wrist) → thumb, index, middle fingers — pathognomonic",
"RADIAL distribution — distinguishes from pectoralis minor (ulnar) and scalene (ulnar with hand oedema)",
"Vascular TOS: radial pulse may be reduced or lost with arm abduction/lateral rotation",
"Pectoralis major clavicular section TrPs are almost always also present — treat together"
],
"treatment_hint": "Trigger point pressure release after inactivating pectoralis major clavicular section TrPs. Correct round-shouldered posture. In-doorway stretch exercise.",
"less_likely": [
{ "muscle": "Scalene", "reason": "Scalene produces ulnar distribution and hand oedema — not radial skip pattern" },
{ "muscle": "Pectoralis Major (sternal section)", "reason": "Sternal section refers to medial epicondyle and ulnar digits, not radial thumb pattern" }
]
},
"result-scm-sternal": {
"type": "result",
"diagnosis": "SCM Trigger Point — Sternal Division",
"confidence": "high",
"wiki_page": "Muscle:Sternocleidomastoid",
"chapter_ref": "Travell & Simons Vol.1 — Ch.7 Sternocleidomastoid",
"notes": "The SCM sternal division refers pain downward to the upper sternal region. The sore throat and dry tingling cough are the pathognomonic distinguishing features when chest pain is the presenting complaint. SCM Compression Test: pincer grip compression of the sternal head relieves the pharyngeal pain and/or cough.",
"key_distinguishing_features": [
"Dry tingling cough TrP — not explained by respiratory illness — pathognomonic for SCM sternal division",
"Sore throat (pharyngeal pain on swallowing) that resolves with SCM pincer compression — SCM Compression Test positive",
"Upper sternal chest pain — not precordial or lateral chest wall",
"Associated cheek, temple, supraorbital, and occipital pain in same referral pattern"
],
"treatment_hint": "Spray and stretch in superior-to-inferior direction. Correct forward head posture. Axial extension exercise. Address perpetuating postural factors.",
"less_likely": [
{ "muscle": "Pectoralis Major", "reason": "Cough TrP and sore throat are not features of pectoral TrPs" },
{ "muscle": "Intercostal Muscles", "reason": "Cough is a symptom here (produced by TrP), not the aggravating factor" }
]
},
"result-iliocostalis-cerv": {
"type": "result",
"diagnosis": "Iliocostalis Cervicis Trigger Point — Spillover Chest Referral",
"confidence": "moderate",
"wiki_page": "Muscle:Iliocostalis_Cervicis",
"chapter_ref": "Travell & Simons Vol.1 — Ch.9 Cervical Paraspinal Muscles",
"notes": "The iliocostalis cervicis refers pain from the cervicothoracic junction upward to the posterior neck and downward to the interscapular area, with spillover to the posterior and lateral chest wall. It is a spillover source rather than a primary anterior chest pain generator. Pain is aggravated by neck movement and sustained postures rather than arm movement or respiration.",
"key_distinguishing_features": [
"Chest pain aggravated by neck rotation or sustained forward head posture — not arm movement or respiration",
"Pain distributes upward-downward (up-and-down pattern) from the cervicothoracic junction",
"Interscapular and posterior neck pain typically present alongside any chest wall component",
"TrP palpable in the lateral paraspinal groove at C7–T4 level"
],
"treatment_hint": "Spray and stretch of erector spinae column. Treat latissimus dorsi TrPs first if present (key TrP activating iliocostalis as satellite). Correct forward head posture. Address workstation ergonomics.",
"less_likely": [
{ "muscle": "Pectoralis Major", "reason": "Pain not aggravated by arm movement; paraspinal TrP palpation positive" },
{ "muscle": "Intercostal Muscles", "reason": "Thoracic rotation not identified as restricted; neck movement is the aggravator" }
]
},
"result-ext-oblique": {
"type": "result",
"diagnosis": "External Oblique Trigger Point — Costal / Subcostal Attachment (Spillover Chest Referral)",
"confidence": "moderate",
"wiki_page": "Muscle:External_Oblique",
"chapter_ref": "Travell & Simons Vol.2 — Ch.49 Abdominal Muscles",
"notes": "Upper external oblique TrPs at the costal attachment refer deep epigastric pain described as heartburn. The Abdominal Tension Test (raising heels while tender area is compressed — if pain INCREASES it is wall-origin) confirms the abdominal wall source and excludes true visceral or cardiac origin.",
"key_distinguishing_features": [
"Pain described as heartburn or deep epigastric burning — not precordial pressure",
"TrP along the lower border of the rib cage or the line of costal attachment — palpable",
"Abdominal Tension Test POSITIVE (pain increases when abdominal muscles are tensed by heel raise) — confirms abdominal wall origin",
"Not worsened by deep inhalation, arm movement, or neck movement"
],
"treatment_hint": "Spray and stretch in a caudal direction with deep inhalation protrusion of the abdomen. Abdominal (diaphragmatic) breathing as corrective exercise. Address visceral perpetuating factors (peptic ulcer, intestinal parasites, cholelithiasis).",
"less_likely": [
{ "muscle": "Diaphragm", "reason": "Abdominal Tension Test positive (wall origin); not worsened at full exhalation" },
{ "muscle": "Pectoralis Major", "reason": "Pain is epigastric / lower chest, not anterior pectoral or precordial; not arm-movement aggravated" },
{ "muscle": "Intercostal Muscles", "reason": "Not aggravated by deep inhalation or thoracic rotation" }
]
},
"result-overlap": {
"type": "overlap",
"text": "Findings are inconclusive or suggest multi-muscle involvement. Perform a systematic palpation screen of all primary chest pain muscles.",
"screen_these": [
"Pectoralis Major — five TrP zones; pincer palpation with arm abducted 90°",
"Pectoralis Minor — pincer palpation in axilla under lateral edge of pectoralis major",
"Subclavius — thumb under medial third of clavicle, arm in adduction",
"Intercostal Muscles — run finger along each rib interspace for full length",
"SCM — sternal and clavicular heads separately",
"Diaphragm — indirect release response; respiratory motion testing",
"External Oblique — costal attachment flat palpation; Abdominal Tension Test",
"Iliocostalis Cervicis — lateral paraspinal groove C7–T4"
],
"wiki_page": "Pain:Chest"
},
"refer-cardiac": {
"type": "neuro_referral",
"urgency": "emergency",
"title": "Serious Pathology NOT Excluded — Do Not Proceed",
"body": "One or more red flag groups (Cardiac, Respiratory, or Gastrointestinal) have not been screened or cleared. Myofascial chest pain can closely mimic ACS, aortic dissection, pulmonary embolism, tension pneumothorax, oesophageal perforation, and acute pancreatitis. Relief of chest pain by vapocoolant spray or local injection does NOT exclude any of these diagnoses. A positive myofascial TrP examination does NOT exclude coexisting serious pathology.",
"action": "Return to the red flag screen. Act on any positive group per that group's action before proceeding. For any uncleared doubt about cardiac origin: refer to Emergency Department immediately."
}
},
"broad_differential": [
{
"id": "bd-1",
"condition": "Costochondritis / Tietze Syndrome",
"confidence": "common",
"mimics": "Anterior chest wall pain at costo-sternal junction, overlapping with parasternal pectoralis major and intercostal TrP patterns",
"distinguishing_feature": "Tietze syndrome: visible and palpable swelling at the costo-sternal junction (distinguishes from costochondritis which lacks swelling). Both: point tenderness directly at the costo-sternal joint. Parasternal internal intercostal TrPs may be responsible for these syndromes.",
"action": "Examine parasternal internal intercostal muscles carefully — TrPs in these muscles may be the cause. If swelling present, refer to rheumatology."
},
{
"id": "bd-2",
"condition": "Thoracic Outlet Syndrome — Vascular",
"confidence": "uncommon",
"mimics": "Anterior shoulder and arm pain resembling subclavius and pectoralis minor TrP patterns",
"distinguishing_feature": "Radial pulse reduction or loss with arm abduction (subclavius mechanism); hand oedema and finger stiffness with scalene mechanism. Wright manoeuvre positive.",
"action": "Check radial pulse in standard and abducted positions. Scalene and subclavius TrP inactivation should be first-line before surgical referral. If neurovascular compromise persists after TrP treatment, refer to vascular surgery."
},
{
"id": "bd-3",
"condition": "Thoracic Outlet Syndrome — Neurological",
"confidence": "uncommon",
"mimics": "Ulnar arm and hand symptoms overlapping with pectoralis minor and scalene TrP patterns",
"distinguishing_feature": "Ulnar nerve distribution (fourth and fifth digits) from medial cord compression by pectoralis minor; median nerve / radial symptoms from lateral cord compression. Hand oedema and finger stiffness with scalene anterior mechanism.",
"action": "Nerve conduction studies. Scalene and pectoralis minor TrP inactivation first-line before surgical referral."
},
{
"id": "bd-4",
"condition": "Peptic Ulcer / Gastro-oesophageal Reflux",
"confidence": "common",
"mimics": "Epigastric burning identical to upper external oblique costal attachment TrP pattern",
"distinguishing_feature": "Visceral pain does NOT increase with the Abdominal Tension Test (pain decreases when abdominal muscles are tensed). Endoscopy / upper GI series confirm. Note: visceral disease ACTIVATES abdominal wall TrPs which persist after the primary disease resolves.",
"action": "Abdominal Tension Test to distinguish wall from visceral origin. Upper GI investigation if Abdominal Tension Test negative."
},
{
"id": "bd-5",
"condition": "Gallbladder Disease / Cholelithiasis",
"confidence": "common",
"mimics": "Right upper quadrant and right lower chest pain overlapping with right external oblique costal attachment TrPs",
"distinguishing_feature": "Visceral pain does NOT increase with Abdominal Tension Test. Ultrasound abdomen. Note: right-sided external oblique TrPs may persist after cholecystectomy.",
"action": "Abdominal Tension Test. Ultrasound abdomen. If TrPs identified alongside visceral pathology, treat both."
},
{
"id": "bd-6",
"condition": "Thoracic Disc Radiculopathy",
"confidence": "uncommon",
"mimics": "Dermatomal chest wall pain in an intercostal distribution overlapping with intercostal TrP pain",
"distinguishing_feature": "Neurological signs in a thoracic dermatomal distribution (paresthesias, altered sensation). MRI thoracic spine. TrPs may develop secondary to radiculopathy and persist after nerve root decompression.",
"action": "Thoracic spine MRI. Treat any secondary intercostal TrPs alongside addressing the primary disc pathology."
},
{
"id": "bd-7",
"condition": "Precordial Catch Syndrome (Texidor's Twinge)",
"confidence": "common",
"mimics": "Brief sharp left-sided anterior chest pain in young patients — overlaps with intercostal and pectoralis minor TrP patterns",
"distinguishing_feature": "Very brief (seconds), sharp stabbing pain typically in the left parasternal area at rest; worsens with deep inhalation but resolves spontaneously. No palpable TrP tenderness.",
"action": "Reassure. If TrPs are palpable, treat accordingly. Cardiac investigation unnecessary in typical young patients."
},
{
"id": "bd-8",
"condition": "Chest Pain Persisting After Myocardial Infarction",
"confidence": "common",
"mimics": "Persistent anterior chest pain after documented MI — may be mistaken for ongoing cardiac ischaemia",
"distinguishing_feature": "Myocardial infarction activates satellite TrPs in the pectoralis major and minor viscero-somatically. These self-perpetuating TrPs persist in the chest wall after cardiac recovery and produce pain similar to the original MI pain. Inactivating the TrPs resolves the persistent chest pain.",
"action": "Screen pectoral muscles for TrPs in all post-MI patients with persistent chest pain. Cardiac status must be confirmed stable before proceeding."
},
{
"id": "bd-11",
"condition": "Herpes Zoster — Pre-eruptive and Post-herpetic",
"confidence": "uncommon",
"mimics": "Unilateral burning or dermatomal chest pain indistinguishable from intercostal TrP pain",
"distinguishing_feature": "Pre-eruptive: burning or shooting quality in a dermatomal band, often with allodynia; immunocompromised or patient aged over 50. Vesicles appear days after pain onset — examine the chest wall at every visit. Post-herpetic: TrP pain (localised ache responding to TrP treatment) coexists with neurogenic pain (shooting, responsive to carbamazepine / gabapentin).",
"action": "If vesicles present: refer to GP urgently — antiviral window is 72 hours. Post-herpetic: treat TrP component alongside antineuralgic therapy."
},
{
"id": "bd-10",
"condition": "Slipping Rib Syndrome (Rib-Tip Syndrome)",
"confidence": "uncommon",
"mimics": "Lower anterior chest and upper abdominal pain overlapping with lower intercostal TrP and diaphragmatic costal attachment TrP patterns",
"distinguishing_feature": "Hooking manoeuvre positive: fingers hooked under the costal margin pull the hypermobile rib forward, reproducing the pain. TrPs in the chondral intercostal muscles, pectoralis major costal section, and transversus abdominis are likely sources of the enthesitis driving the rib hypermobility.",
"action": "Hooking manoeuvre to confirm. Inactivate TrPs in costal attachment muscles. Refer to thoracic surgery if hypermobile rib segment requires resection."
}
]
}