DiagnosticTree/Olecranon

{

 "model": "bayesian_lr_scoring",
 "version": "1.0",
 "description": "Probabilistic scoring model for posterior elbow / olecranon pain. Two muscles drawn from T&S Vol.1: Triceps Brachii (attachment TrP at the distal insertion, TrP4) and Serratus Posterior Superior (olecranon accent in spillover zone). Triceps TrP4 is the bold primary referrer (prior 0.60); serratus posterior superior is the non-bold spillover source (prior 0.40).",
 "thresholds": {
   "early_exit_posterior": 0.82,
   "early_exit_gap": 0.25,
   "pairwise_trigger": 0.15
 },
 "muscles": {
   "triceps_TrP4": {
     "label": "Triceps Brachii (distal attachment)",
     "prior": 0.6,
     "page": "Muscle:Triceps_Brachii",
     "key_trp_note": "This is an attachment TrP \u2014 almost always secondary to a central TrP in the long, lateral, or deep medial head of triceps. Primary treatment must be directed at the responsible central TrP, not the olecranon attachment site itself. Palpate back along the induration from the olecranon toward the muscle belly to find the driver. Latissimus dorsi and serratus posterior superior are key TrP sources that can drive satellite TrPs in the triceps \u2014 always consider them when triceps TrPs recur.",
     "subtitle": "Focal tender spot at the olecranon tip, deep through the tendon; worse on pushing or straightening the elbow against resistance; no bursal swelling"
   },
   "serratus_posterior_superior": {
     "label": "Serratus Posterior Superior",
     "prior": 0.4,
     "page": "Muscle:Serratus_Posterior",
     "key_trp_note": "Serratus posterior superior TrPs refer a wide arc: deep under the scapula (inaccessible at rest \u2014 scapula must be fully abducted to palpate) \u2192 posterior deltoid and triceps region \u2192 olecranon accent \u2192 ulnar forearm \u2192 5th digit. The olecranon pain is one stop in this wider pattern. Scalene TrPs are the primary driver of serratus posterior superior satellite TrPs \u2014 always examine the neck. Treat scalenes first if found.",
     "subtitle": "Olecranon pain is part of a wide arc: deep scapular ache you cannot reach \u2192 posterior arm \u2192 elbow accent \u2192 ulnar forearm \u2192 5th digit; respiratory overload history"
   }
 },
 "questions": [
   {
     "id": "q_pain_extent",
     "text": "What is the full extent of the pain \u2014 beyond just the elbow tip?",
     "sublabel": "Choose the description that best captures the whole pattern",
     "type": "choice",
     "answers": [
       {
         "id": "olecranon_only",
         "label": "Elbow tip only \u2014 pain stays right at the back of the elbow; nothing above or below",
         "sublabel": "No radiation up into the arm or down into the forearm",
         "lr": {
           "triceps_TrP4": 7.5,
           "serratus_posterior_superior": 0.25
         }
       },
       {
         "id": "elbow_plus_upper_arm",
         "label": "Elbow tip plus aching in the back of the upper arm or toward the shoulder",
         "sublabel": "Pain extends proximally into the posterior arm",
         "lr": {
           "triceps_TrP4": 2.5,
           "serratus_posterior_superior": 1.5
         }
       },
       {
         "id": "wide_arc_scapula_to_finger",
         "label": "Elbow tip is part of a wide arc \u2014 deep under the shoulder blade, through the arm, down to the little finger",
         "sublabel": "The scapular ache and arm referral are present alongside the elbow pain",
         "lr": {
           "triceps_TrP4": 0.2,
           "serratus_posterior_superior": 8.0
         }
       },
       {
         "id": "elbow_plus_ulnar_forearm",
         "label": "Elbow tip plus aching or numbness down the inner (little-finger) side of the forearm",
         "sublabel": "Pain or numbness tracks down toward the 5th digit",
         "lr": {
           "triceps_TrP4": 0.3,
           "serratus_posterior_superior": 6.5
         }
       }
     ]
   },
   {
     "id": "q_provocation",
     "text": "What activity or situation most reliably provokes or worsens the elbow pain?",
     "sublabel": "Choose the best match",
     "type": "choice",
     "answers": [
       {
         "id": "pushing_pressing",
         "label": "Pushing things away, press-ups, dips, or straightening the elbow against resistance",
         "sublabel": "Any activity requiring forceful elbow extension",
         "lr": {
           "triceps_TrP4": 7.0,
           "serratus_posterior_superior": 0.3
         }
       },
       {
         "id": "sustained_forward_elbow",
         "label": "Sustained postures with the elbow held forward or unsupported for long periods",
         "sublabel": "Desk work, driving, writing \u2014 elbow out in front without rest",
         "lr": {
           "triceps_TrP4": 3.5,
           "serratus_posterior_superior": 1.5
         }
       },
       {
         "id": "respiratory_or_cough",
         "label": "During or after a period of prolonged coughing, respiratory illness, or breathing difficulties",
         "sublabel": "Pain started or significantly worsened with a respiratory episode",
         "lr": {
           "triceps_TrP4": 0.25,
           "serratus_posterior_superior": 8.0
         }
       },
       {
         "id": "reaching_overhead",
         "label": "Reaching behind, carrying with arms extended, or sitting with shoulders elevated at a high desk",
         "sublabel": "Overhead or reaching postures",
         "lr": {
           "triceps_TrP4": 0.5,
           "serratus_posterior_superior": 5.5
         }
       }
     ]
   },
   {
     "id": "q_elbow_loading",
     "text": "Does straightening the elbow against resistance \u2014 or pushing something away \u2014 specifically reproduce the elbow tip pain?",
     "sublabel": "Resisted elbow extension test",
     "type": "binary",
     "answers": [
       {
         "id": "yes",
         "label": "Yes \u2014 elbow tip pain is specifically reproduced by pushing or resisted extension",
         "lr": {
           "triceps_TrP4": 6.0,
           "serratus_posterior_superior": 0.3
         }
       },
       {
         "id": "no",
         "label": "No \u2014 elbow loading does not change the pain; posture or breathing matters more",
         "lr": {
           "triceps_TrP4": 0.35,
           "serratus_posterior_superior": 5.5
         }
       }
     ]
   },
   {
     "id": "q_scapular_ache",
     "text": "Is there a deep aching under the shoulder blade on the same side \u2014 an ache you cannot quite reach even when pressing on it?",
     "sublabel": "The scapula covers the source; the ache is felt underneath it",
     "type": "binary",
     "answers": [
       {
         "id": "yes",
         "label": "Yes \u2014 a deep unreachable ache under the shoulder blade is present",
         "lr": {
           "triceps_TrP4": 0.25,
           "serratus_posterior_superior": 8.0
         }
       },
       {
         "id": "no",
         "label": "No \u2014 no scapular ache; pain is at the elbow only or in the arm",
         "lr": {
           "triceps_TrP4": 2.5,
           "serratus_posterior_superior": 0.5
         }
       }
     ]
   },
   {
     "id": "q_digit_symptoms",
     "text": "Is there any numbness, tingling, or aching into the little (5th) finger or the inner edge of the ring finger?",
     "sublabel": "Referred C8\u2013T1 sensation into the ulnar digits \u2014 present in serratus posterior superior spillover",
     "type": "binary",
     "answers": [
       {
         "id": "yes",
         "label": "Yes \u2014 numbness or aching reaches the 5th finger or ulnar ring finger",
         "lr": {
           "triceps_TrP4": 0.3,
           "serratus_posterior_superior": 7.0
         }
       },
       {
         "id": "no",
         "label": "No \u2014 no finger symptoms",
         "lr": {
           "triceps_TrP4": 1.8,
           "serratus_posterior_superior": 0.6
         }
       }
     ]
   },
   {
     "id": "q_swelling_check",
     "text": "Is there any visible swelling or a soft fluctuant lump at the tip of the elbow?",
     "sublabel": "Olecranon bursitis screen \u2014 if present, this algorithm does not apply",
     "type": "binary",
     "answers": [
       {
         "id": "yes",
         "label": "Yes \u2014 visible swelling or fluctuance at the olecranon",
         "lr": {
           "triceps_TrP4": 0.1,
           "serratus_posterior_superior": 0.1
         }
       },
       {
         "id": "no",
         "label": "No \u2014 no swelling; deep spot tenderness only",
         "lr": {
           "triceps_TrP4": 2.0,
           "serratus_posterior_superior": 1.5
         }
       }
     ]
   },
   {
     "id": "q_extension_strength",
     "text": "Can the patient fully straighten the elbow against gravity \u2014 is elbow extension strength intact?",
     "sublabel": "Distal triceps rupture screen \u2014 loss of active extension strength is a red flag",
     "type": "binary",
     "answers": [
       {
         "id": "yes",
         "label": "Yes \u2014 full active extension against gravity; strength is intact",
         "lr": {
           "triceps_TrP4": 2.0,
           "serratus_posterior_superior": 1.8
         }
       },
       {
         "id": "no",
         "label": "No \u2014 cannot fully extend the elbow against gravity; weakness present",
         "lr": {
           "triceps_TrP4": 0.1,
           "serratus_posterior_superior": 0.1
         }
       }
     ]
   },
   {
     "id": "q_tenderness_location",
     "text": "Where is the most tender spot on palpation?",
     "sublabel": "Press firmly in each location to find the most exquisite point",
     "type": "choice",
     "answers": [
       {
         "id": "olecranon_tip_deep",
         "label": "Right at the olecranon tip \u2014 deep, through-the-tendon spot tenderness; no fluid",
         "sublabel": "Pain is deep to the skin and subcutaneous tissue, through the aponeurosis",
         "lr": {
           "triceps_TrP4": 6.0,
           "serratus_posterior_superior": 0.35
         }
       },
       {
         "id": "under_scapula",
         "label": "Deep under the shoulder blade \u2014 only accessible when the arm is swung well forward",
         "sublabel": "Tenderness found only when the scapula is abducted away from the ribs",
         "lr": {
           "triceps_TrP4": 0.25,
           "serratus_posterior_superior": 8.0
         }
       },
       {
         "id": "posterior_arm_belly",
         "label": "In the back of the upper arm muscle belly \u2014 somewhere above the elbow in the triceps",
         "sublabel": "A taut band or nodule in the posterior arm, not at the elbow tip itself",
         "lr": {
           "triceps_TrP4": 3.5,
           "serratus_posterior_superior": 1.5
         }
       },
       {
         "id": "not_well_localised",
         "label": "Not well localised \u2014 pain is felt but hard to pinpoint on palpation",
         "lr": {
           "triceps_TrP4": 1.2,
           "serratus_posterior_superior": 1.2
         }
       }
     ]
   }
 ],
 "pairwise": [
   {
     "id": "pw_triceps_serratus",
     "pair": [
       "triceps_TrP4",
       "serratus_posterior_superior"
     ],
     "text": "Tiebreaker \u2014 Triceps (distal attachment) vs Serratus Posterior Superior",
     "question": "Does pushing or pressing specifically reproduce the elbow tip pain, OR is the elbow pain part of a wider pattern that includes a deep scapular ache or 5th-finger numbness?",
     "sublabel": "The key question: is this a local loading problem, or a wide referred pain pattern?",
     "answers": [
       {
         "id": "loading_reproduces",
         "label": "Pushing / pressing specifically reproduces the olecranon pain \u2014 local loading problem",
         "lr": {
           "triceps_TrP4": 6.0,
           "serratus_posterior_superior": 0.25
         }
       },
       {
         "id": "wide_pattern",
         "label": "Elbow pain is part of a wider pattern \u2014 scapular ache, arm referral, or 5th-finger numbness present",
         "lr": {
           "triceps_TrP4": 0.25,
           "serratus_posterior_superior": 6.0
         }
       }
     ]
   }
 ],
 "treatment_dag": {
   "edges": [
     {
       "from": "serratus_posterior_superior",
       "to": "triceps_TrP4",
       "type": "key_satellite",
       "label": "Serratus posterior superior TrPs can drive satellite TrPs in the triceps \u2014 treat serratus first; triceps attachment tenderness may resolve without direct treatment"
     }
   ],
   "edge_type_labels": {
     "key_satellite": "Treat first \u2014 key TrP driving satellite",
     "functional_unit": "Treat concurrently in same session",
     "secondary_load": "Treat after primary resolves",
     "antagonist_risk": "\u26a0 Treat in alternating cycles \u2014 reactive activation risk"
   }
 },
 "region_label": "Posterior Elbow / Olecranon Pain",
 "emergency": [
   {
     "id": "rf-e1",
     "label": "Acute compartment syndrome",
     "question": "Severe, disproportionate forearm or arm pain that is worsening despite rest? Pain sharply increased by passive finger or wrist extension? Forearm feels tense or woody on palpation? Paraesthesia or pallor of the hand?"
   },
   {
     "id": "rf-e2",
     "label": "Septic joint (septic arthritis of the elbow)",
     "question": "Acutely hot, swollen, and exquisitely tender elbow with severe restriction of all movement? Fever, rigors, or systemic sepsis signs? Recent bacteraemia, intravenous drug use, or immunosuppression?"
   }
 ],
 "urgent": [
   {
     "id": "rf-u1",
     "label": "Septic olecranon bursitis",
     "question": "Erythema, warmth, and tenderness over the olecranon bursa with fever? Skin broken or penetrating injury over the elbow tip? Immunocompromised patient?"
   },
   {
     "id": "rf-u2",
     "label": "Fracture or dislocation",
     "question": "History of significant trauma \u2014 fall on outstretched hand, direct blow, or forced hyperextension? Visible deformity, bony tenderness, or inability to extend the elbow? Flake sign on X-ray suggesting avulsion?"
   },
   {
     "id": "rf-u3",
     "label": "Cellulitis of the posterior elbow",
     "question": "Spreading erythema, warmth, and swelling of the skin over or around the olecranon without a clearly fluctuant bursa? Tender lymph nodes? Fever or systemic signs?"
   },
   {
     "id": "rf-u4",
     "label": "Distal triceps tendon rupture",
     "question": "Acute posterior elbow pain after an eccentric load (fall on outstretched hand, forced flexion against contraction)? Inability to actively extend the elbow against gravity? Palpable gap above the olecranon?"
   }
 ]

}