DiagnosticTree/DorsalWristAndHand
{
"model": "bayesian_lr_scoring",
"version": "1.0",
"region_label": "Dorsal Wrist and Hand Pain",
"description": "Probabilistic scoring model for dorsal wrist and hand pain. Sources span four zones: the local forearm extensor mass (extensor carpi radialis brevis - the principal referrer - and longus, extensor digitorum, extensor indicis, extensor carpi ulnaris), an intrinsic hand muscle (first dorsal interosseous), the neck (scalenus minimus), and the shoulder girdle (subscapularis, coracobrachialis, latissimus dorsi, serratus posterior superior) whose pain reaches the dorsal hand as spillover. Structural differential from Ng et al. 2024, Forman et al. 2005, and the intersection-syndrome literature.",
"thresholds": {
"early_exit_posterior": 0.55,
"early_exit_gap": 0.18,
"pairwise_trigger": 0.15
},
"muscles": {
"ecrb": {
"label": "Extensor Carpi Radialis Brevis",
"prior": 0.130435,
"page": "Muscle:Extensor_Carpi_Radialis",
"key_trp_note": "The extensor carpi radialis brevis is the principal myofascial source of dorsal wrist and hand pain. Its referral spreads broadly across the back of the hand rather than to one focal point, and it is the muscle most often driving a 'tennis elbow' enthesopathy. Reproduced by resisted wrist extension and gripping. Examine and treat with the radial wrist extensor longus and the finger extensors, with which it shares the common extensor origin.",
"subtitle": "Pain across the BACK OF THE HAND broadly (not focal), with the lateral epicondyle / dorsal wrist; the principal dorsal-hand referrer; worse on resisted wrist extension and gripping"
},
"ecrl": {
"label": "Extensor Carpi Radialis Longus",
"prior": 0.086957,
"page": "Muscle:Extensor_Carpi_Radialis",
"key_trp_note": "The longus refers more toward the lateral epicondyle and the dorsoradial wrist and anatomical snuffbox than the brevis, whose pattern is broader across the back of the hand. The two are examined and treated together as the radial wrist extensor pair; both are provoked by resisted wrist extension and gripping.",
"subtitle": "Lateral epicondyle and the dorsoradial wrist / anatomical snuffbox region; worse on resisted wrist extension; part of the radial wrist extensor pair with the brevis"
},
"extensor_digitorum": {
"label": "Extensor Digitorum",
"prior": 0.086957,
"page": "Muscle:Extensor_Digitorum",
"key_trp_note": "Refers pain down the dorsum of the hand into the specific finger served by the involved fibres - the pattern follows the finger. The ring and little finger fibres additionally refer proximally to the lateral epicondyle. Provoked by resisted finger extension and firm gripping. Almost always accompanied by extensor carpi ulnaris involvement when the ulnar fibres are active.",
"subtitle": "Pain down the back of the hand INTO a specific finger (and, for the ring/little finger fibres, up to the lateral epicondyle); worse on resisted finger extension and gripping"
},
"extensor_indicis": {
"label": "Extensor Indicis",
"prior": 0.086957,
"page": "Muscle:Extensor_Indicis",
"key_trp_note": "The deepest dorsal forearm muscle. Its referral stays focally at the radial side of the dorsal wrist and does NOT extend into the fingers - the key differentiator from the rest of the finger extensor group. Characteristically the culprit of last resort: when all the more superficial extensors have been treated and a residual dorsal-radial wrist ache remains, the extensor indicis is the likely source. Seldom active without coexisting extensor digitorum involvement.",
"subtitle": "Focal pain at the RADIAL side of the dorsal wrist (NOT into the fingers); the 'last resort' source - persists after the main extensor mass has been treated"
},
"extensor_carpi_ulnaris": {
"label": "Extensor Carpi Ulnaris",
"prior": 0.086957,
"page": "Muscle:Extensor_Carpi_Ulnaris",
"key_trp_note": "The least commonly involved wrist extensor under ordinary conditions. Its referral is focal at the ulnar side of the dorsal wrist, distinct from the radial-side and broad patterns of the other extensors. Look for a precipitating cause - fracture, immobilisation, or a global frozen-shoulder pattern - rather than simple overuse. Almost never active without a coexisting extensor digitorum trigger point; treat the two together. Serratus posterior superior can drive it as a satellite.",
"subtitle": "Focal pain at the ULNAR side of the dorsal wrist; worse on gripping with the wrist turned toward the little-finger side; usually follows trauma, casting, or a frozen shoulder"
},
"first_dorsal_interosseous": {
"label": "First Dorsal Interosseous",
"prior": 0.086957,
"page": "Muscle:Interossei",
"key_trp_note": "The largest of the interossei, filling the dorsal thumb web. Refers strongly down the radial side of the index finger and deeply through both the dorsum and palm of the hand, with spillover into the dorsal wrist and hand. The second most frequent source of referred palm pain. A Heberden's node at the index distal interphalangeal joint is a useful guide and its tenderness typically resolves immediately after trigger-point injection. Nearly always co-active with the adductor pollicis.",
"subtitle": "Pain strongly down the radial index finger and deeply through the dorsum AND palm of the hand, with spillover into the dorsal wrist; a Heberden's node at the index DIP joint is a guide"
},
"subscapularis": {
"label": "Subscapularis",
"prior": 0.086957,
"page": "Muscle:Subscapularis",
"key_trp_note": "The anterior rotator-cuff muscle and the initial layer of the frozen-shoulder cascade. Its essential referral is the posterior shoulder, but the diagnostically distinctive accent is a strap-like band of pain and tenderness around the wrist - predominantly dorsal - that classically makes patients move their wristwatch to the other arm. The key clinical test is reciprocal limitation of glenohumeral abduction and lateral rotation. Suspect it when dorsal wrist pain is accompanied by posterior shoulder pain and restricted shoulder motion.",
"subtitle": "Posterior shoulder pain with a distinctive STRAP-LIKE band of pain around the wrist, predominantly the dorsal surface ('moved the wristwatch to the other arm'); reciprocal limitation of shoulder abduction and lateral rotation"
},
"coracobrachialis": {
"label": "Coracobrachialis",
"prior": 0.086957,
"page": "Muscle:Coracobrachialis",
"key_trp_note": "A deep anterior shoulder muscle and a residual, last-to-be-found source - discovered after anterior deltoid and biceps have been cleared yet deep anterior shoulder pain persists. Its referral is a distinctive interrupted 'skip' column: anterior shoulder, then posterior arm, dorsal forearm, and dorsum of the hand to the middle fingertip, sparing the elbow and wrist joints themselves. The Back-rub Test (reaching behind the back) is painful and resolves with treatment.",
"subtitle": "Anterior shoulder pain with an interrupted column down the posterior arm and dorsal forearm to the back of the hand, SKIPPING the elbow and wrist, possibly to the middle fingertip; a deep residual source"
},
"scalenus_minimus": {
"label": "Scalenus Minimus",
"prior": 0.086957,
"page": "Muscle:Scalene",
"key_trp_note": "An inconstant deep scalene muscle (part of the scalene complex). Scalene trigger points are a key driver of satellite trigger points throughout the extensor digitorum group, so their referred pain can reach the dorsal forearm and hand. The neck must always be examined when a dorsal-hand extensor trigger point is found, since treating the forearm without addressing a scalene driver leads to recurrence. May contribute to a thoracic-outlet-type picture.",
"subtitle": "Neck-origin pain spilling down the arm to the dorsal forearm and hand; a key driver of satellite trigger points throughout the finger-extensor group; examine the neck"
},
"latissimus_dorsi": {
"label": "Latissimus Dorsi",
"prior": 0.086957,
"page": "Muscle:Latissimus_Dorsi",
"key_trp_note": "Refers from the inferior scapular angle and mid-back down the posterior arm to the ulnar forearm and hand, including the ring and little fingers, reaching the dorsal hand as distal spillover. One of the four pseudo-thoracic-outlet muscles (with subscapularis, pectoralis major, and teres major). Suspect it when dorsal-hand pain is accompanied by mid-back or posterior axillary-fold pain.",
"subtitle": "Mid-back and inferior scapular pain spilling down the back of the arm to the ulnar forearm and hand (ring and little fingers); a member of the pseudo-thoracic-outlet group"
},
"serratus_posterior_superior": {
"label": "Serratus Posterior Superior",
"prior": 0.086957,
"page": "Muscle:Serratus_Posterior",
"key_trp_note": "Refers a deep ache from under the scapula (reachable only with the scapula fully abducted) through the posterior arm, with ulnar forearm/hand and 5th digit spillover, and can produce referred C8-T1 numbness that is not a true neurological deficit. Activated by respiratory overload. A key driver of satellite trigger points in the finger-extensor group, and itself driven by scalene trigger points - examine the neck.",
"subtitle": "Deep unreachable ache under the scapula spilling to the ulnar forearm, hand, and little finger, with referred C8-T1 numbness; respiratory overload history; scapula must be abducted to palpate"
}
},
"questions": [
{
"id": "q_zone",
"text": "Where does the overall pain seem to come from?",
"sublabel": "Choose the dominant origin of the whole pattern",
"type": "choice",
"answers": [
{
"id": "forearm_hand",
"label": "The FOREARM and HAND themselves - pain is at or just above the wrist",
"sublabel": "Local forearm/hand source",
"lr": {
"ecrb": 3.0,
"ecrl": 3.0,
"extensor_digitorum": 3.0,
"extensor_indicis": 3.0,
"extensor_carpi_ulnaris": 3.0,
"first_dorsal_interosseous": 2.5,
"subscapularis": 0.3,
"coracobrachialis": 0.3,
"scalenus_minimus": 0.4,
"latissimus_dorsi": 0.3,
"serratus_posterior_superior": 0.3
}
},
{
"id": "shoulder",
"label": "The SHOULDER - shoulder pain that extends down to the hand",
"sublabel": "Shoulder-girdle source",
"lr": {
"ecrb": 0.3,
"ecrl": 0.3,
"extensor_digitorum": 0.3,
"extensor_indicis": 0.3,
"extensor_carpi_ulnaris": 0.5,
"first_dorsal_interosseous": 0.4,
"subscapularis": 6.0,
"coracobrachialis": 6.0,
"scalenus_minimus": 0.6,
"latissimus_dorsi": 4.0,
"serratus_posterior_superior": 1.5
}
},
{
"id": "neck_upper_back",
"label": "The NECK or UPPER BACK - pain spreading from there down the arm",
"sublabel": "Neck / posterior thorax source",
"lr": {
"ecrb": 0.3,
"ecrl": 0.3,
"extensor_digitorum": 0.4,
"extensor_indicis": 0.4,
"extensor_carpi_ulnaris": 0.5,
"first_dorsal_interosseous": 0.4,
"subscapularis": 0.6,
"coracobrachialis": 0.5,
"scalenus_minimus": 6.0,
"latissimus_dorsi": 2.0,
"serratus_posterior_superior": 6.0
}
},
{
"id": "hand_only",
"label": "The HAND itself, especially the index finger and thumb web",
"sublabel": "Intrinsic hand source",
"lr": {
"ecrb": 1.2,
"ecrl": 0.8,
"extensor_digitorum": 1.5,
"extensor_indicis": 1.5,
"extensor_carpi_ulnaris": 1.0,
"first_dorsal_interosseous": 6.0,
"subscapularis": 0.4,
"coracobrachialis": 0.5,
"scalenus_minimus": 0.4,
"latissimus_dorsi": 0.4,
"serratus_posterior_superior": 0.4
}
}
]
},
{
"id": "q_dorsal_focus",
"text": "On the back of the wrist and hand, where is the pain most focused?",
"sublabel": "The location on the dorsum",
"type": "choice",
"answers": [
{
"id": "radial_wrist",
"label": "RADIAL (thumb) side of the dorsal wrist",
"sublabel": "Dorsoradial wrist - focal",
"lr": {
"ecrb": 1.5,
"ecrl": 3.0,
"extensor_digitorum": 0.8,
"extensor_indicis": 6.0,
"extensor_carpi_ulnaris": 0.4,
"first_dorsal_interosseous": 1.0,
"subscapularis": 0.6,
"coracobrachialis": 0.6,
"scalenus_minimus": 0.8,
"latissimus_dorsi": 0.5,
"serratus_posterior_superior": 0.5
}
},
{
"id": "ulnar_wrist",
"label": "ULNAR (little-finger) side of the dorsal wrist",
"sublabel": "Dorsoulnar wrist - focal",
"lr": {
"ecrb": 0.6,
"ecrl": 0.5,
"extensor_digitorum": 1.2,
"extensor_indicis": 0.5,
"extensor_carpi_ulnaris": 6.5,
"first_dorsal_interosseous": 0.8,
"subscapularis": 0.8,
"coracobrachialis": 0.6,
"scalenus_minimus": 0.8,
"latissimus_dorsi": 1.2,
"serratus_posterior_superior": 1.5
}
},
{
"id": "broad_back_of_hand",
"label": "BROADLY across the whole back of the hand",
"sublabel": "Diffuse dorsal hand",
"lr": {
"ecrb": 6.0,
"ecrl": 2.0,
"extensor_digitorum": 2.0,
"extensor_indicis": 0.6,
"extensor_carpi_ulnaris": 0.8,
"first_dorsal_interosseous": 1.5,
"subscapularis": 0.6,
"coracobrachialis": 1.5,
"scalenus_minimus": 0.8,
"latissimus_dorsi": 0.8,
"serratus_posterior_superior": 0.8
}
},
{
"id": "into_a_finger",
"label": "Down the back of the hand INTO one or more fingers",
"sublabel": "Following a finger ray",
"lr": {
"ecrb": 0.8,
"ecrl": 0.6,
"extensor_digitorum": 6.0,
"extensor_indicis": 0.5,
"extensor_carpi_ulnaris": 1.0,
"first_dorsal_interosseous": 2.5,
"subscapularis": 0.5,
"coracobrachialis": 1.2,
"scalenus_minimus": 0.8,
"latissimus_dorsi": 1.0,
"serratus_posterior_superior": 1.0
}
},
{
"id": "index_and_palm",
"label": "The index finger and deep into the palm as well as the dorsum",
"sublabel": "Index ray + palm depth",
"lr": {
"ecrb": 0.8,
"ecrl": 0.6,
"extensor_digitorum": 1.0,
"extensor_indicis": 1.0,
"extensor_carpi_ulnaris": 0.6,
"first_dorsal_interosseous": 6.5,
"subscapularis": 0.4,
"coracobrachialis": 0.8,
"scalenus_minimus": 0.5,
"latissimus_dorsi": 0.5,
"serratus_posterior_superior": 0.5
}
}
]
},
{
"id": "q_provocation",
"text": "Which activity most reliably brings on the pain?",
"sublabel": "Choose the single strongest aggravator",
"type": "choice",
"answers": [
{
"id": "wrist_extension_grip",
"label": "Cocking the wrist back or gripping (lifting with palm down, push-ups, yoga on the hands)",
"sublabel": "Resisted wrist extension / weight-bearing",
"lr": {
"ecrb": 6.0,
"ecrl": 4.0,
"extensor_digitorum": 1.2,
"extensor_indicis": 1.5,
"extensor_carpi_ulnaris": 1.2,
"first_dorsal_interosseous": 0.6,
"subscapularis": 0.5,
"coracobrachialis": 0.5,
"scalenus_minimus": 0.6,
"latissimus_dorsi": 0.6,
"serratus_posterior_superior": 0.6
}
},
{
"id": "finger_extension",
"label": "Straightening the fingers against resistance",
"sublabel": "Resisted finger extension",
"lr": {
"ecrb": 1.0,
"ecrl": 0.8,
"extensor_digitorum": 6.0,
"extensor_indicis": 2.5,
"extensor_carpi_ulnaris": 1.0,
"first_dorsal_interosseous": 0.6,
"subscapularis": 0.4,
"coracobrachialis": 0.5,
"scalenus_minimus": 0.6,
"latissimus_dorsi": 0.6,
"serratus_posterior_superior": 0.8
}
},
{
"id": "ulnar_grip",
"label": "Gripping with the wrist turned toward the little-finger side",
"sublabel": "Loaded ulnar deviation",
"lr": {
"ecrb": 0.8,
"ecrl": 0.6,
"extensor_digitorum": 1.2,
"extensor_indicis": 0.6,
"extensor_carpi_ulnaris": 6.0,
"first_dorsal_interosseous": 0.8,
"subscapularis": 0.6,
"coracobrachialis": 0.5,
"scalenus_minimus": 0.6,
"latissimus_dorsi": 1.0,
"serratus_posterior_superior": 1.0
}
},
{
"id": "pincer_grip",
"label": "Sustained fine pinch or pincer grip (sewing, writing, small tools, tight club grip)",
"sublabel": "Pincer-grip overload",
"lr": {
"ecrb": 0.8,
"ecrl": 0.6,
"extensor_digitorum": 0.8,
"extensor_indicis": 1.0,
"extensor_carpi_ulnaris": 0.7,
"first_dorsal_interosseous": 6.5,
"subscapularis": 0.4,
"coracobrachialis": 0.5,
"scalenus_minimus": 0.5,
"latissimus_dorsi": 0.5,
"serratus_posterior_superior": 0.5
}
},
{
"id": "shoulder_arm_load",
"label": "Reaching, lifting overhead, or reaching behind the back",
"sublabel": "Shoulder-girdle load",
"lr": {
"ecrb": 0.4,
"ecrl": 0.4,
"extensor_digitorum": 0.5,
"extensor_indicis": 0.5,
"extensor_carpi_ulnaris": 0.7,
"first_dorsal_interosseous": 0.6,
"subscapularis": 5.5,
"coracobrachialis": 5.5,
"scalenus_minimus": 0.8,
"latissimus_dorsi": 4.0,
"serratus_posterior_superior": 1.5
}
},
{
"id": "breathing_cough",
"label": "Deep breathing, coughing, or after a respiratory illness",
"sublabel": "Respiratory overload",
"lr": {
"ecrb": 0.4,
"ecrl": 0.4,
"extensor_digitorum": 0.5,
"extensor_indicis": 0.5,
"extensor_carpi_ulnaris": 0.6,
"first_dorsal_interosseous": 0.5,
"subscapularis": 0.6,
"coracobrachialis": 0.6,
"scalenus_minimus": 3.5,
"latissimus_dorsi": 0.8,
"serratus_posterior_superior": 6.0
}
}
]
},
{
"id": "q_finger_target",
"text": "If pain reaches the fingers, which fingers?",
"sublabel": "Distribution into the digits",
"type": "choice",
"answers": [
{
"id": "index_radial",
"label": "The index finger (radial side) and thumb web",
"sublabel": "Index / thumb web",
"lr": {
"ecrb": 0.8,
"ecrl": 1.0,
"extensor_digitorum": 1.2,
"extensor_indicis": 2.0,
"extensor_carpi_ulnaris": 0.6,
"first_dorsal_interosseous": 6.0,
"subscapularis": 0.5,
"coracobrachialis": 1.0,
"scalenus_minimus": 0.7,
"latissimus_dorsi": 0.5,
"serratus_posterior_superior": 0.5
}
},
{
"id": "ring_little",
"label": "The ring and little fingers / ulnar side of the hand",
"sublabel": "Ulnar fingers",
"lr": {
"ecrb": 0.7,
"ecrl": 0.6,
"extensor_digitorum": 3.5,
"extensor_indicis": 0.6,
"extensor_carpi_ulnaris": 2.0,
"first_dorsal_interosseous": 0.8,
"subscapularis": 0.6,
"coracobrachialis": 0.6,
"scalenus_minimus": 1.0,
"latissimus_dorsi": 2.5,
"serratus_posterior_superior": 3.5
}
},
{
"id": "middle_fingertip",
"label": "Out to the tip of the MIDDLE finger, with the arm pain skipping the elbow and wrist",
"sublabel": "Middle fingertip, skip pattern",
"lr": {
"ecrb": 0.6,
"ecrl": 0.5,
"extensor_digitorum": 1.5,
"extensor_indicis": 0.5,
"extensor_carpi_ulnaris": 0.5,
"first_dorsal_interosseous": 0.8,
"subscapularis": 0.8,
"coracobrachialis": 6.5,
"scalenus_minimus": 0.8,
"latissimus_dorsi": 0.8,
"serratus_posterior_superior": 0.8
}
},
{
"id": "specific_single",
"label": "A single specific finger, following that finger's line",
"sublabel": "One finger ray",
"lr": {
"ecrb": 0.8,
"ecrl": 0.7,
"extensor_digitorum": 6.0,
"extensor_indicis": 1.0,
"extensor_carpi_ulnaris": 1.0,
"first_dorsal_interosseous": 1.2,
"subscapularis": 0.5,
"coracobrachialis": 0.8,
"scalenus_minimus": 0.7,
"latissimus_dorsi": 0.8,
"serratus_posterior_superior": 0.8
}
},
{
"id": "no_fingers",
"label": "It stays at the wrist - no finger involvement",
"sublabel": "Wrist only",
"lr": {
"ecrb": 1.2,
"ecrl": 1.2,
"extensor_digitorum": 0.5,
"extensor_indicis": 3.0,
"extensor_carpi_ulnaris": 1.5,
"first_dorsal_interosseous": 0.6,
"subscapularis": 1.2,
"coracobrachialis": 0.6,
"scalenus_minimus": 0.9,
"latissimus_dorsi": 0.8,
"serratus_posterior_superior": 0.9
}
}
]
},
{
"id": "q_shoulder_wristband",
"text": "Is there posterior shoulder pain together with a band of pain or tenderness around the wrist (especially the back), or restricted shoulder motion?",
"sublabel": "Subscapularis screen - the strap-like dorsal wrist band is its distinctive accent",
"type": "binary",
"answers": [
{
"id": "yes",
"label": "Yes - posterior shoulder pain with a wrist band and/or restricted shoulder abduction and rotation",
"lr": {
"ecrb": 0.5,
"ecrl": 0.5,
"extensor_digitorum": 0.6,
"extensor_indicis": 0.6,
"extensor_carpi_ulnaris": 0.8,
"first_dorsal_interosseous": 0.6,
"subscapularis": 7.0,
"coracobrachialis": 1.5,
"scalenus_minimus": 0.8,
"latissimus_dorsi": 1.5,
"serratus_posterior_superior": 1.0
}
},
{
"id": "no",
"label": "No - no shoulder pain or shoulder-motion restriction",
"lr": {
"ecrb": 1.2,
"ecrl": 1.2,
"extensor_digitorum": 1.1,
"extensor_indicis": 1.1,
"extensor_carpi_ulnaris": 1.0,
"first_dorsal_interosseous": 1.1,
"subscapularis": 0.2,
"coracobrachialis": 0.7,
"scalenus_minimus": 1.0,
"latissimus_dorsi": 0.8,
"serratus_posterior_superior": 1.0
}
}
]
},
{
"id": "q_proximal_back",
"text": "Is there accompanying neck pain, mid-back pain, or a deep ache under the shoulder blade?",
"sublabel": "Neck / posterior thorax screen - scalene, latissimus, and serratus posterior superior sources",
"type": "binary",
"answers": [
{
"id": "yes",
"label": "Yes - neck, mid-back, or deep sub-scapular ache accompanies the hand pain",
"lr": {
"ecrb": 0.5,
"ecrl": 0.5,
"extensor_digitorum": 0.7,
"extensor_indicis": 0.7,
"extensor_carpi_ulnaris": 0.9,
"first_dorsal_interosseous": 0.7,
"subscapularis": 0.9,
"coracobrachialis": 0.8,
"scalenus_minimus": 5.0,
"latissimus_dorsi": 3.5,
"serratus_posterior_superior": 5.5
}
},
{
"id": "no",
"label": "No - no neck or back component",
"lr": {
"ecrb": 1.2,
"ecrl": 1.2,
"extensor_digitorum": 1.1,
"extensor_indicis": 1.1,
"extensor_carpi_ulnaris": 1.0,
"first_dorsal_interosseous": 1.1,
"subscapularis": 1.0,
"coracobrachialis": 1.0,
"scalenus_minimus": 0.3,
"latissimus_dorsi": 0.5,
"serratus_posterior_superior": 0.3
}
}
]
},
{
"id": "q_persistence",
"text": "Did this dorsal wrist pain remain AFTER the main forearm extensor muscles were treated, staying focal at one spot?",
"sublabel": "Extensor indicis is the residual 'last resort' source at the radial dorsal wrist",
"type": "binary",
"answers": [
{
"id": "yes",
"label": "Yes - a focal residual ache persisted after the main extensors were addressed",
"lr": {
"ecrb": 0.7,
"ecrl": 0.8,
"extensor_digitorum": 0.8,
"extensor_indicis": 6.0,
"extensor_carpi_ulnaris": 1.2,
"first_dorsal_interosseous": 1.0,
"subscapularis": 0.8,
"coracobrachialis": 1.0,
"scalenus_minimus": 0.9,
"latissimus_dorsi": 0.9,
"serratus_posterior_superior": 0.9
}
},
{
"id": "no",
"label": "No - this is the primary or only pain, not a residual one",
"lr": {
"ecrb": 1.2,
"ecrl": 1.1,
"extensor_digitorum": 1.1,
"extensor_indicis": 0.4,
"extensor_carpi_ulnaris": 1.0,
"first_dorsal_interosseous": 1.0,
"subscapularis": 1.0,
"coracobrachialis": 1.0,
"scalenus_minimus": 1.0,
"latissimus_dorsi": 1.0,
"serratus_posterior_superior": 1.0
}
}
]
},
{
"id": "q_palpation",
"text": "Where does firm palpation most precisely reproduce the familiar dorsal wrist/hand pain?",
"sublabel": "The reproducing tender point - the most specific localiser",
"type": "choice",
"answers": [
{
"id": "radial_extensor_mass",
"label": "Just below the elbow crease in the radial wrist-extensor mass (ulnar to brachioradialis)",
"sublabel": "Radial wrist extensor location (brevis/longus)",
"lr": {
"ecrb": 6.0,
"ecrl": 5.0,
"extensor_digitorum": 1.0,
"extensor_indicis": 0.6,
"extensor_carpi_ulnaris": 0.6,
"first_dorsal_interosseous": 0.4,
"subscapularis": 0.4,
"coracobrachialis": 0.4,
"scalenus_minimus": 0.5,
"latissimus_dorsi": 0.4,
"serratus_posterior_superior": 0.4
}
},
{
"id": "mid_extensor_forearm",
"label": "In the middle of the dorsal forearm extensor mass",
"sublabel": "Extensor digitorum location",
"lr": {
"ecrb": 1.0,
"ecrl": 0.8,
"extensor_digitorum": 6.0,
"extensor_indicis": 1.5,
"extensor_carpi_ulnaris": 1.2,
"first_dorsal_interosseous": 0.4,
"subscapularis": 0.4,
"coracobrachialis": 0.4,
"scalenus_minimus": 0.5,
"latissimus_dorsi": 0.4,
"serratus_posterior_superior": 0.4
}
},
{
"id": "deep_radius_ulna",
"label": "Deep, midway between the radius and ulna in the distal forearm (through the tendons)",
"sublabel": "Extensor indicis location",
"lr": {
"ecrb": 0.6,
"ecrl": 0.5,
"extensor_digitorum": 1.2,
"extensor_indicis": 6.5,
"extensor_carpi_ulnaris": 0.8,
"first_dorsal_interosseous": 0.4,
"subscapularis": 0.4,
"coracobrachialis": 0.4,
"scalenus_minimus": 0.5,
"latissimus_dorsi": 0.4,
"serratus_posterior_superior": 0.4
}
},
{
"id": "ulnar_border_forearm",
"label": "A hand's breadth below the elbow near the sharp dorsal edge of the ulna (twitch turns the hand to the little-finger side)",
"sublabel": "Extensor carpi ulnaris location",
"lr": {
"ecrb": 0.5,
"ecrl": 0.5,
"extensor_digitorum": 1.2,
"extensor_indicis": 0.6,
"extensor_carpi_ulnaris": 6.5,
"first_dorsal_interosseous": 0.5,
"subscapularis": 0.4,
"coracobrachialis": 0.4,
"scalenus_minimus": 0.5,
"latissimus_dorsi": 0.5,
"serratus_posterior_superior": 0.6
}
},
{
"id": "thumb_web_muscle",
"label": "In the muscle of the dorsal thumb web (between thumb and index metacarpals)",
"sublabel": "First dorsal interosseous location",
"lr": {
"ecrb": 0.5,
"ecrl": 0.4,
"extensor_digitorum": 0.6,
"extensor_indicis": 0.6,
"extensor_carpi_ulnaris": 0.5,
"first_dorsal_interosseous": 7.0,
"subscapularis": 0.4,
"coracobrachialis": 0.4,
"scalenus_minimus": 0.4,
"latissimus_dorsi": 0.4,
"serratus_posterior_superior": 0.4
}
},
{
"id": "axilla_scapula_front",
"label": "Deep in the armpit against the front of the shoulder blade (scapula abducted)",
"sublabel": "Subscapularis location",
"lr": {
"ecrb": 0.4,
"ecrl": 0.4,
"extensor_digitorum": 0.4,
"extensor_indicis": 0.4,
"extensor_carpi_ulnaris": 0.5,
"first_dorsal_interosseous": 0.4,
"subscapularis": 7.0,
"coracobrachialis": 1.0,
"scalenus_minimus": 0.5,
"latissimus_dorsi": 0.8,
"serratus_posterior_superior": 0.5
}
},
{
"id": "deep_anterior_shoulder",
"label": "Deep in the front of the shoulder, beneath the deltoid (deeper than the deltoid)",
"sublabel": "Coracobrachialis location",
"lr": {
"ecrb": 0.4,
"ecrl": 0.4,
"extensor_digitorum": 0.4,
"extensor_indicis": 0.4,
"extensor_carpi_ulnaris": 0.5,
"first_dorsal_interosseous": 0.5,
"subscapularis": 1.0,
"coracobrachialis": 7.0,
"scalenus_minimus": 0.5,
"latissimus_dorsi": 0.6,
"serratus_posterior_superior": 0.5
}
},
{
"id": "neck_scalene",
"label": "In the side of the neck (scalene muscles)",
"sublabel": "Scalenus minimus location",
"lr": {
"ecrb": 0.4,
"ecrl": 0.4,
"extensor_digitorum": 0.5,
"extensor_indicis": 0.5,
"extensor_carpi_ulnaris": 0.5,
"first_dorsal_interosseous": 0.4,
"subscapularis": 0.5,
"coracobrachialis": 0.5,
"scalenus_minimus": 7.0,
"latissimus_dorsi": 0.5,
"serratus_posterior_superior": 1.2
}
},
{
"id": "posterior_axillary_fold",
"label": "In the posterior axillary fold / side of the back (latissimus dorsi)",
"sublabel": "Latissimus dorsi location",
"lr": {
"ecrb": 0.4,
"ecrl": 0.4,
"extensor_digitorum": 0.5,
"extensor_indicis": 0.5,
"extensor_carpi_ulnaris": 0.6,
"first_dorsal_interosseous": 0.4,
"subscapularis": 0.8,
"coracobrachialis": 0.5,
"scalenus_minimus": 0.5,
"latissimus_dorsi": 7.0,
"serratus_posterior_superior": 0.8
}
},
{
"id": "under_scapula_ribs",
"label": "Deep against a rib under the abducted scapula (upper back)",
"sublabel": "Serratus posterior superior location",
"lr": {
"ecrb": 0.4,
"ecrl": 0.4,
"extensor_digitorum": 0.5,
"extensor_indicis": 0.5,
"extensor_carpi_ulnaris": 0.6,
"first_dorsal_interosseous": 0.4,
"subscapularis": 0.6,
"coracobrachialis": 0.5,
"scalenus_minimus": 1.2,
"latissimus_dorsi": 0.8,
"serratus_posterior_superior": 7.0
}
}
]
}
],
"pairwise": [
{
"id": "pw_ecrb_ecrl",
"pair": [
"ecrb",
"ecrl"
],
"text": "Tiebreaker - Extensor Carpi Radialis Brevis vs Longus",
"question": "Is the pain spread BROADLY across the back of the hand, or more focal toward the dorsoradial wrist and snuffbox?",
"sublabel": "Brevis refers broadly across the hand; longus more to the dorsoradial wrist",
"answers": [
{
"id": "broad",
"label": "Broadly across the back of the hand - brevis",
"lr": {
"ecrb": 5.0,
"ecrl": 0.4
}
},
{
"id": "dorsoradial",
"label": "Focal dorsoradial wrist / snuffbox - longus",
"lr": {
"ecrb": 0.4,
"ecrl": 5.0
}
}
]
},
{
"id": "pw_ecrl_ei",
"pair": [
"ecrl",
"extensor_indicis"
],
"text": "Tiebreaker - Extensor Carpi Radialis Longus vs Extensor Indicis",
"question": "Is the radial dorsal wrist pain provoked by resisted WRIST extension, or is it a deep focal residual ache that persisted after the main extensors were treated?",
"sublabel": "Wrist extensor vs the deep 'last resort' index extensor",
"answers": [
{
"id": "wrist_ext",
"label": "Provoked by resisted wrist extension - extensor carpi radialis longus",
"lr": {
"ecrl": 5.0,
"extensor_indicis": 0.4
}
},
{
"id": "residual",
"label": "Deep focal residual ache, not in the fingers - extensor indicis",
"lr": {
"ecrl": 0.4,
"extensor_indicis": 5.0
}
}
]
},
{
"id": "pw_edc_ecu",
"pair": [
"extensor_digitorum",
"extensor_carpi_ulnaris"
],
"text": "Tiebreaker - Extensor Digitorum vs Extensor Carpi Ulnaris",
"question": "Does the pain run INTO a finger (with resisted finger extension), or stay focal at the ulnar wrist (with loaded ulnar-deviation gripping)?",
"sublabel": "Finger extensor vs ulnar wrist extensor",
"answers": [
{
"id": "finger",
"label": "Into a finger, resisted finger extension - extensor digitorum",
"lr": {
"extensor_digitorum": 5.0,
"extensor_carpi_ulnaris": 0.4
}
},
{
"id": "ulnar_wrist",
"label": "Focal ulnar wrist, loaded ulnar deviation - extensor carpi ulnaris",
"lr": {
"extensor_digitorum": 0.4,
"extensor_carpi_ulnaris": 5.0
}
}
]
},
{
"id": "pw_subsc_corb",
"pair": [
"subscapularis",
"coracobrachialis"
],
"text": "Tiebreaker - Subscapularis vs Coracobrachialis",
"question": "Is there POSTERIOR shoulder pain with a wrist band and restricted shoulder rotation, or ANTERIOR shoulder pain with a column skipping the elbow and wrist to the middle fingertip?",
"sublabel": "Posterior shoulder + wrist band vs anterior shoulder + skip pattern",
"answers": [
{
"id": "posterior_band",
"label": "Posterior shoulder, dorsal wrist band, restricted rotation - subscapularis",
"lr": {
"subscapularis": 5.5,
"coracobrachialis": 0.3
}
},
{
"id": "anterior_skip",
"label": "Anterior shoulder, skip column to middle fingertip - coracobrachialis",
"lr": {
"subscapularis": 0.3,
"coracobrachialis": 5.5
}
}
]
},
{
"id": "pw_scmin_sps",
"pair": [
"scalenus_minimus",
"serratus_posterior_superior"
],
"text": "Tiebreaker - Scalenus Minimus vs Serratus Posterior Superior",
"question": "Does the pain originate in the SIDE OF THE NECK, or as a deep UNREACHABLE ache under the shoulder blade with respiratory provocation?",
"sublabel": "Neck source vs deep posterior sub-scapular source",
"answers": [
{
"id": "neck",
"label": "Side of the neck - scalenus minimus",
"lr": {
"scalenus_minimus": 5.0,
"serratus_posterior_superior": 0.3
}
},
{
"id": "subscapular",
"label": "Deep unreachable sub-scapular ache, respiratory - serratus posterior superior",
"lr": {
"scalenus_minimus": 0.3,
"serratus_posterior_superior": 5.0
}
}
]
}
],
"treatment_dag": {
"edges": [
{
"from": "ecrb",
"to": "ecrl",
"type": "functional_unit",
"label": "Radial wrist extensor pair - examine and treat together"
},
{
"from": "ecrb",
"to": "extensor_digitorum",
"type": "functional_unit",
"label": "Share the common extensor origin; treat the extensor mass together"
},
{
"from": "extensor_digitorum",
"to": "extensor_indicis",
"type": "functional_unit",
"label": "Extensor indicis is the residual deep finger extensor; treat after the superficial mass, examine together"
},
{
"from": "extensor_digitorum",
"to": "extensor_carpi_ulnaris",
"type": "functional_unit",
"label": "The ulnar wrist extensor is almost never involved without the finger extensors; examine together"
},
{
"from": "scalenus_minimus",
"to": "extensor_digitorum",
"type": "key_satellite",
"label": "Scalene trigger points drive satellite finger-extensor trigger points; treat the neck first"
},
{
"from": "serratus_posterior_superior",
"to": "extensor_carpi_ulnaris",
"type": "key_satellite",
"label": "Serratus posterior superior can drive the ulnar wrist extensor as a satellite; address the upper back"
},
{
"from": "subscapularis",
"to": "latissimus_dorsi",
"type": "functional_unit",
"label": "Pseudo-thoracic-outlet group - examine subscapularis, latissimus, teres major, pectoralis major together"
},
{
"from": "subscapularis",
"to": "coracobrachialis",
"type": "secondary_load",
"label": "Coracobrachialis is a deep residual anterior-shoulder source; address after the primary shoulder muscles"
},
{
"from": "first_dorsal_interosseous",
"to": "extensor_digitorum",
"type": "secondary_load",
"label": "First dorsal interosseous pain may coexist with extensor mass involvement; treat the intrinsic hand muscle in its own right"
}
],
"edge_type_labels": {
"key_satellite": "Treat first - key TrP driving satellite",
"functional_unit": "Treat concurrently in same session",
"secondary_load": "Treat after primary resolves",
"antagonist_risk": "Treat in alternating cycles - reactive activation risk"
}
},
"emergency": [
{
"id": "rf-e1",
"label": "Acute compartment syndrome of the forearm",
"question": "Severe, disproportionate, worsening forearm pain unrelieved by rest or elevation? Pain sharply increased by passive finger or wrist movement? Tense or woody forearm? Paraesthesia or pallor of the hand? Recent fracture, crush, or tight cast?",
"source": "Standard limb emergency screen"
},
{
"id": "rf-e2",
"label": "Septic arthritis of the wrist",
"question": "Acutely hot, swollen, exquisitely tender wrist with severe, deep, unrelenting pain and a barely moveable joint? Fever or constitutional symptoms? Recent infection, penetrating injury (including animal/human bite), IV drug use, or immunosuppression?",
"source": "Forman et al. 2005 (septic arthritis); Ng et al. 2024 (infective tenosynovitis)"
},
{
"id": "rf-e3",
"label": "Infective (suppurative) extensor tenosynovitis",
"question": "Dorsal wrist redness, swelling, and warmth with pain on passive finger movement, following a penetrating injury, bite, or wound? Fever or spreading erythema? Restricted finger extension? Needs urgent surgical and antibiotic management.",
"source": "Ng et al. 2024 (infective tenosynovitis case)"
},
{
"id": "rf-e4",
"label": "Lunate / perilunate dislocation (carpal dislocation)",
"question": "High-energy wrist trauma or a fall on the outstretched hand with marked swelling, deformity, severe pain, and often median-nerve paraesthesia (radial three-and-a-half digits)? These are the disastrous-if-missed end-stage of severe ligament disruption. The lateral x-ray is key: the 'empty/spilled teacup' sign (capitate no longer seated in the lunate concavity) signals a perilunate dislocation, while a volarly tilted lunate not articulating with the capitate signals a lunate dislocation; on the AP, the 'piece-of-pie/pizza' sign (triangular lunate) and disrupted Gilula's arcs are the clues, with a 'signet-ring' scaphoid indicating scapholunate flexion. Needs emergent reduction and hand-surgery referral.",
"source": "EM Cases Ep.189 (Sayal, Distefano, Helman 2023); Forman et al. 2005"
}
],
"urgent": [
{
"id": "rf-u1",
"label": "Scaphoid fracture / occult carpal fracture",
"question": "Fall on the outstretched hand (especially a young adult)? Tenderness in the anatomical snuffbox or over a carpal bone? NOTE: up to 20% of scaphoid fractures are radiographically occult initially - snuffbox tenderness after a fall must be splinted and re-imaged at 2-3 weeks even if the first X-ray is normal, because nonunion and avascular necrosis follow a missed scaphoid fracture.",
"source": "Forman et al. 2005"
},
{
"id": "rf-u2",
"label": "Scapholunate dissociation / carpal instability",
"question": "Wrist pain out of proportion to the injury after a fall, with a clicking, popping, or audible 'clunk' on movement? Tenderness at the scapholunate interval (1.5 cm distal to Lister's tubercle)? Positive Watson (scaphoid shift) test? Untreated scapholunate dissociation progresses to advanced carpal collapse (SLAC).",
"source": "Forman et al. 2005; Ng et al. 2024"
},
{
"id": "rf-u3",
"label": "Kienbock's disease (avascular necrosis of the lunate)",
"question": "Exercise-related dorsal wrist pain with restricted flexion-extension and diminished grip strength, often in a man aged 20-40 in the dominant hand, with a vague or distant injury history? Central dorsal wrist tenderness over the lunate? Plain X-ray may be normal early - MRI is needed.",
"source": "Ng et al. 2024"
},
{
"id": "rf-u4",
"label": "Posterior interosseous nerve entrapment / distal PIN syndrome",
"question": "Deep dorsal-radial forearm aching with weakness of finger or thumb extension? A dorsal wrist ganglion compressing the terminal PIN? Progressive motor loss rather than pure pain? Distinguish from a myofascial extensor source by objective extensor weakness.",
"source": "Forman et al. 2005 (Table 2); Ng et al. 2024 (ganglion compressing terminal PIN)"
},
{
"id": "rf-u5",
"label": "Inflammatory or crystal arthritis (RA, gout, CPPD)",
"question": "Dorsal wrist pain, stiffness, and swelling - the wrist is the most affected joint in rheumatoid arthritis? Morning stiffness over an hour, multiple joints, or systemic features? Acute hot swollen joint suggesting gout/pseudogout? Tenosynovitis with the extensor digitorum communis? Needs inflammatory screen and rheumatology input.",
"source": "Ng et al. 2024; Forman et al. 2005 (systemic causes)"
},
{
"id": "rf-u6",
"label": "Distal radioulnar joint (DRUJ) injury, including Galeazzi fracture",
"question": "The 'forgotten joint of the wrist'. Pain on resisted PRONATION and SUPINATION (not just flexion/extension), with point tenderness over the DRUJ (the divot between the distal radius and ulnar styloid) and a positive shuck/ballottement test (excess movement of the ulnar head versus the other side) or piano-key sign? Mechanism is forced pronation/supination (power tools, a fall while carrying a load, gripping a steering wheel in a crash) as well as any fall on the outstretched hand. Often OCCULT on x-ray - look for >2 mm DRUJ widening on the PA and loss of radius-ulna overlap on the lateral. A Galeazzi pattern (distal-third radius fracture with DRUJ dislocation) needs ORIF. Splint in an ABOVE-ELBOW cast with the forearm SUPINATED (a short below-elbow splint is the classic pitfall); a missed DRUJ injury causes chronic supination deficit and pain.",
"source": "EM Cases Ep.189 (Sayal, Distefano, Helman 2023); Hemmati et al. CFP 2024"
},
{
"id": "rf-u7",
"label": "Dorsal Barton's fracture / dorsal distal radius fracture-dislocation",
"question": "After a fall on the outstretched hand: a dorsal distal-radius injury that on the lateral view shows a fracture of the DORSAL LIP of the distal radius extending into the joint, usually with subluxation or dislocation of the radiocarpal joint? A dorsal Barton's appears minor on x-ray but is often unstable and needs distinguishing from a Colles fracture, because management is more often surgical. Scrutinise the lateral view; refer for orthopaedic consideration of fixation.",
"source": "EM Cases Ep.189 (Sayal, Distefano, Helman 2023)"
}
],
"broad_differential": [
{
"id": "bd-1",
"condition": "Occult dorsal wrist ganglion",
"confidence": "common",
"mimics": "Dorsal wrist pain on extension, sometimes with no visible swelling - overlaps the extensor-mass and dorsal-wrist TrP patterns",
"distinguishing_feature": "One of the most common causes of dorsal wrist pain. Arises most often from the scapholunate joint; point tenderness over the scapholunate interval during wrist hyperextension, with or without a palpable mass. An occult ganglion (no visible lump) can still cause pain and may compress the terminal posterior interosseous nerve. TrP pain is reproduced by muscle palpation, not by focal scapholunate-interval pressure.",
"action": "Ultrasound is highly accurate and can guide aspiration; MRI detects occult ganglia and peri-ganglionic inflammation and maps the deep tract (which must be excised to prevent recurrence if surgery is undertaken). Reassurance, activity modification, aspiration, or excision.",
"source": "Ng et al. 2024"
},
{
"id": "bd-2",
"condition": "Scapholunate ligament tear / dorsal capsular impingement (capsulitis)",
"confidence": "common",
"mimics": "Dorsal-central wrist pain on the loaded extended wrist (push-ups, yoga) - overlaps the weight-bearing provocation of the radial wrist extensors",
"distinguishing_feature": "The scapholunate ligament tear, dorsal capsular inflammation, and occult ganglia are the three most common MRI findings in dorsal wrist pain on extension. Scapholunate tear: tenderness at the scapholunate interval, pain out of proportion to injury, positive Watson test, possible clunk; widening >4 mm on a clenched-fist view. Dorsal wrist capsular impingement: pain and swelling localised dorsal-central during passive extension as the capsule is pinched between the scaphoid and the ECRB tendon. TrP pain is reproduced by forearm-muscle palpation, not by joint-line provocation.",
"action": "Radiographs (including clenched-fist view); MRI is best for the ligament, MR arthrography most sensitive. Dorsal capsular impingement is largely clinical - rest, activity modification, anti-inflammatories, occasionally steroid injection or surgery. Refer carpal instability promptly to prevent SLAC.",
"source": "Ng et al. 2024"
},
{
"id": "bd-3",
"condition": "Intersection syndrome",
"confidence": "uncommon",
"mimics": "Pain and crepitus on the dorsoradial forearm 4-6 cm proximal to Lister's tubercle - directly overlaps the radial wrist extensor TrP zone and is commonly underdiagnosed",
"distinguishing_feature": "Pain and tenderness (often with crepitus) where the first-compartment thumb muscles cross the radial wrist extensors, 4-6 cm proximal to Lister's tubercle - more proximal than de Quervain's. Provoked by resisted wrist extension and by twisting hand motions with radial deviation; pain with resisted pronation. More common in men and in the dominant hand, in repetitive wrist flexion-extension (rowing, racquet sports, weightlifting). The radial wrist extensor TrPs can coexist and reproduce the same pain on resisted testing.",
"action": "Largely clinical; ultrasound or MRI shows the tenosynovial/peritendinous change if needed. Activity modification, wrist-extension splinting, eccentric loading, and TrP release of the radial wrist extensors; steroid injection if it persists beyond 2-3 weeks. Conservative care succeeds in ~60%.",
"source": "Fan & Grimes 2025; Forman et al. 2005"
},
{
"id": "bd-4",
"condition": "De Quervain's tenosynovitis",
"confidence": "common",
"mimics": "Radial-sided wrist and dorsal thumb pain - overlaps the dorsoradial referral of the radial wrist extensors and extensor indicis",
"distinguishing_feature": "Tenderness and swelling localised to the FIRST extensor compartment at the radial styloid (more distal and radial than intersection syndrome); positive Finkelstein test (ulnar deviation with the thumb in the fist reproduces pain). More common in women, over 40, and with forceful gripping plus ulnar deviation or repetitive thumb use (caring for an infant, needlework). TrP pain is reproduced by forearm-muscle palpation, not by the Finkelstein manoeuvre.",
"action": "Clinical diagnosis (Finkelstein); ultrasound may show synovial thickening. Thumb spica splint, anti-inflammatories, activity modification, corticosteroid injection; surgical release if refractory.",
"source": "Forman et al. 2005; Fan & Grimes 2025"
},
{
"id": "bd-5",
"condition": "Carpal boss / 2nd-3rd carpometacarpal osteoarthritis",
"confidence": "uncommon",
"mimics": "Focal dorsal pain and a bony bump at the base of the 2nd/3rd metacarpals - can be mistaken for a first-dorsal-interosseous or extensor-mass source",
"distinguishing_feature": "A bony protuberance at the dorsal base of the 2nd or 3rd metacarpal, with point tenderness, dull pain, and limited wrist extension - typically ages 20-40, worse with wrist-extension sport (gymnastics, golf, racquet). May develop an overlying adventitial bursa or ganglion. The 2nd/3rd CMC joints are normally near-immobile, so their osteoarthritis usually follows trauma. TrP pain has no fixed bony prominence.",
"action": "Lateral or 'carpal boss view' radiograph; CT delineates the anatomy, MRI shows associated bursa/ganglion or OA. Splinting, activity modification, anti-inflammatories; excision only for persistent significant symptoms.",
"source": "Ng et al. 2024"
},
{
"id": "bd-6",
"condition": "Triquetral fracture",
"confidence": "uncommon",
"mimics": "Dorsal and dorso-ulnar wrist pain and tenderness after a fall - overlaps the extensor carpi ulnaris and ulnar-sided patterns",
"distinguishing_feature": "Point tenderness and swelling on the dorsal/dorso-ulnar wrist after a fall on the outstretched hand in ulnar deviation; the second most common carpal fracture. A dorsal cortical chip is the usual pattern and ~40% are radiographically occult (small, obscured by overlapping bone). Often with dorsal carpal ligament injury. TrP pain has no bony point tenderness and no trauma-linked swelling.",
"action": "Radiographs; CT is the gold standard if X-rays are negative but suspicion persists; MRI shows marrow oedema. Most are non-displaced and treated with splint/cast immobilisation.",
"source": "Ng et al. 2024"
},
{
"id": "bd-7",
"condition": "Extensor tendinosis / tenosynovitis (EDC, EPL, EDM)",
"confidence": "uncommon",
"mimics": "Dorsal wrist pain along the extensor tendons - overlaps the extensor digitorum and extensor mass TrP referral",
"distinguishing_feature": "Tendinosis itself is usually asymptomatic but can cause dorsal wrist pain via peritendinitis; tenosynovitis gives dorsal swelling and pain on finger movement. The extensor digitorum communis is most often affected, especially in early RA, gout, and chronic infection (TB). The extensor pollicis longus can rupture where it angles around Lister's tubercle. Crystal aggregates within thickened tenosynovium on ultrasound point to gout. TrP pain is reproduced by palpating the forearm muscle belly, not the tendon sheath.",
"action": "Ultrasound or MRI characterises the tendon and sheath. Treat any underlying inflammatory/crystal/infective cause. Splinting, anti-inflammatories; surgical management for impending or actual extensor pollicis longus rupture.",
"source": "Ng et al. 2024"
},
{
"id": "bd-8",
"condition": "Superficial radial nerve entrapment (Wartenberg's syndrome)",
"confidence": "uncommon",
"mimics": "Dorsoradial wrist and thumb pain - overlaps the radial wrist extensor and extensor indicis referral",
"distinguishing_feature": "Burning or electric-shock pain with paraesthesia/numbness over the dorsoradial wrist and thumb, in the superficial radial nerve territory; objective sensory loss and a positive Tinel sign over the distal lateral forearm; worsened by the radial-nerve neurodynamic test and by tight watch straps or bracelets. TrP referral produces aching pain without objective sensory deficit. Can coexist with de Quervain's (false-positive Finkelstein).",
"action": "Clinical; sensory nerve conduction study confirms. Remove external compression (watch strap), activity modification, splinting, neural gliding; rarely decompression.",
"source": "Fan & Grimes 2025; Forman et al. 2005 (Table 2)"
},
{
"id": "bd-9",
"condition": "Cervical radiculopathy (C6-C7) / thoracic outlet syndrome",
"confidence": "uncommon",
"mimics": "Dorsal forearm and hand pain referred from the neck - overlaps the distal spillover of the scalene, serratus posterior superior, and latissimus sources",
"distinguishing_feature": "Dermatomal sensory deficit, reflex change, or myotomal weakness with neck pain and a positive Spurling test point to radiculopathy; positive EAST/Roos and ULTT with ulnar-sided symptoms point to thoracic outlet syndrome. A proximal lesion must be excluded before the wrist is examined. TrP referral produces no reflex change or true dermatomal deficit and IS reproduced by muscle palpation - and scalene TrPs frequently coexist with and drive a TOS picture.",
"action": "Full neurological and upper-quarter examination; Spurling, ULNT, EAST. MRI cervical spine and EMG/NCS if neurological signs. Treat coexisting scalene/shoulder-girdle TrPs concurrently - they may be the dominant or driving source.",
"source": "Forman et al. 2005; Fan & Grimes 2025; WikiMSK"
},
{
"id": "bd-10",
"condition": "Triangular fibrocartilage complex (TFCC) injury",
"confidence": "uncommon",
"mimics": "Ulnar-sided dorsal/volar wrist pain, often after a fall or a distal radius fracture - overlaps the extensor carpi ulnaris referral and the ulnar dorsal-wrist zone",
"distinguishing_feature": "The 'meniscus of the wrist' and primary stabiliser of the distal radioulnar joint. Ulnar-sided pain aggravated by pronation/supination and gripping, often dating to a fall on an extended, pronated, ulnarly deviated wrist recalled as a 'sprain', or following a distal radius fracture. A positive fovea sign (tenderness in the soft-tissue depression between the ulnar styloid and the flexor carpi ulnaris tendon) and a positive TFCC compression test (axial load with the wrist ulnarly deviated reproduces the pain) point to it; assess DRUJ stability with the ballottement test. Distinguish from extensor carpi ulnaris tendinopathy/subluxation (the ECU synergy test and a subluxing tendon on supination-to-flexion) and from a myofascial extensor source (reproduced by forearm-muscle palpation, no foveal tenderness).",
"action": "Fovea sign, TFCC compression and DRUJ ballottement tests; radiographs for ulnar variance (a long ulna predisposes), with MRI or MR arthrography where x-rays are normal and suspicion persists (plain MRI and ultrasound are less reliable on the ulnar side). Splinting (volar wrist, or above-elbow if pronosupination must be limited); refer for arthroscopy and repair, or ulnar-shortening osteotomy for positive ulnar variance, if unstable or persistent.",
"source": "Hemmati et al. CFP 2024; EM Cases Ep.189 (Sayal, Distefano, Helman 2023)"
}
]
}