Do not stop at dementia. The board move is dementia plus posterior-column body plus light-near pupil. One spirochete ties the whole map together.
Challenge Before Reveal
A retired tailor develops paranoid spending, a stomping wide-based gait, shock-like calf pains, absent ankle reflexes, lost vibration at the toes, and pupils that constrict for near focus but not to light.
Which organism makes this one disease instead of three random problems?
Treponema pallidum. General paresis explains behavior change. Tabes dorsalis explains dorsal-column sensory ataxia, lightning pains, and absent reflexes. Argyll Robertson pupil explains accommodation without light reaction.
Mechanism Map
Four Routes, One Spirochete
Each clue lights a different neuroanatomic route.
Route 1Cortex changes the person.Dementia is not enough. Dementia plus body clues is late syphilis.
Route 2Dorsal root becomes pain plus absent reflexes.The afferent limb fails, so ankle reflexes disappear.
Route 3Position sense goes dark.Vibration and toe position vanish. Vision compensates until eyes close.
Route 4Near works. Light fails.That split is the Argyll Robertson lock in late syphilis.
Image Anchors
See The Real Clues
Three anchors only: organism, pupil split, posterior-column injury.
Treponema pallidum
Argyll Robertson pupil
Tabes dorsalis cord
Battle Tabs
Four Doors, One Spirochete
Tap through the faces of neurosyphilis. The page is not asking for isolated buzzwords. It is asking for the unifying map.
Aqueous crystalline penicillin G IV for neurosyphilis, ocular syphilis, or otosyphilis. Severe allergy means desensitization.
Name Locks
Challenge Before Reveal
Localize Before You Name It
Q1. The stem says dementia and behavior change. What must you check before choosing Alzheimer disease?
Correct. Dementia alone is broad. Dementia plus lightning pain, lost vibration, absent reflexes, positive Romberg, or Argyll Robertson pupil is late syphilis until proven otherwise.
Q2. The patient has neurologic findings and a reactive syphilis screen. What confirms the CNS lane?
Yes. Blood serology supports infection. CSF testing supports CNS involvement. Treatment is IV aqueous penicillin G.
Etiology Board
Mr. Alvarez has paranoid spending, lightning leg pain, lost vibration at the toes, absent ankle reflexes, and pupils that constrict for reading but not for light.
General paresiscortex changes the person
Dorsal rootpain plus weak reflex arc
Tabesposterior-column position loss
Argylllight-near split
Treponema pallidum wins because it covers all four routes.
Cortexgeneral paresis
Rootlightning pain, absent reflexes
Columnlost vibration, sensory ataxia
Pupilaccommodates, does not react
clinical Walkthrough
30 Vignettes, One At A Time
Each case forces the same move: find the clue, run the chain, kill the distractor, then lock the clinical action.
Medically reviewed by Kaitlyn Cocuzzo, MD and Fatima Ali, DO · Last reviewed June 2026
Bone Wizardry is an independent educational resource for visual learning in the medical sciences. It is not affiliated with, endorsed by, or sponsored by any licensing or examination board, contains no real or recalled examination questions, and does not guarantee any educational or examination outcome.