[Lipstick-Triggered Task-Specific Tremor in Woman After Shoulder Fall]
A 67-year-old woman performed daily activities such as eating soup, cutting food with a knife and fork, and drinking from a glass without difficulty. Yet, whenever she raised her right arm to apply lipstick, her arm and shoulder would abruptly jerk.
< p>The jerks began roughly six months after a fall that directly injured her right shoulder. Over the preceding five years, the woman had endured frequent episodes, and she was eventually referred to neurologists. In 2019, Cavallieri, Moro, Fraix and colleagues published a case in Tremor and Other Hyperkinetic Movements, describing the phenomenon as a task-specific “lipstick dystonic tremor.”
Miming the Motion Changed Nothing
The patient had no family history of neurological disease. The fall resulted in shoulder pain, bruising, swelling, and stiffness. An X‑ray revealed no bony damage, and she was discharged in a sling‑style immobilizer. Symptoms subsided within about three weeks after a short course of physical therapy.
Several months after the fall, the rhythmic jerks manifested in the right arm and shoulder.
The clinicians asked her to repeat the lipstick‑application motion while keeping the arm in the identical configuration; no abnormal jerks occurred. Only the actual task produced the movements, confirming that the disorder was task‑specific rather than position‑specific. In other words, the trigger was the action itself, not the arm’s static posture.
Displacement of attention to unrelated motor tasks did not alter the jerks, and objective signs of suggestibility were absent, distinguishing this condition from a functional movement disorder.
Muscle Recordings and Normal Scans
Electromyographic recordings revealed pseudorhythmic bursts occurring approximately five times per second, lasting roughly 78 ms, that emerged during the lipstick maneuver. These bursts affected multiple shoulder and chest muscles, including the pectoralis major and minor, the deltoid, and the teres major.
Brain MRI demonstrated only age‑related white‑matter changes, while the cervical spine MRI was normal.
When Injury Comes Before Abnormal Movement
The clinicians categorized the condition as a peripherally induced movement disorder, in which abnormal motions arise after injury to a body segment external to the brain and spinal cord. The National Institute of Neurological Disorders and Stroke includes trauma among the etiologies of acquired dystonia, and the Cleveland Clinic reports that focal dystonia may sometimes follow a traumatic insult.
Neuroscientists Francisco Cardoso and Joseph Jankovic established 1995 clinical criteria to assess whether a preceding injury plausibly causes a movement disorder. These criteria consider trauma severity, regional specificity of the movement, and the elapsed time between injury and symptom onset. The authors showed that the patient satisfied these criteria, making a coincidental etiology improbable.
The terminology itself is evolving. A 2025 Dystonia journal editorial raises the question of whether task‑specific tremor should be regarded as a form of task‑specific dystonia. The editors further state that repetitive jerky movements of a body region in dystonia should cease to be labeled as tremor, a revision that may influence future case nomenclature.
Injections Brought Relief
The clinicians performed botulinum toxin injections into the clavicular head of the pectoralis major, guided by the recorded muscle activity. Within three weeks, the abnormal jerks markedly diminished.
Botulinum toxin injections are typically the most effective therapeutic option for focal dystonia, with symptom relief often beginning within a few days and persisting for several months; repeated injections are therefore standard of care.
She subsequently underwent repeat botulinum toxin injections approximately every five months, delivering roughly 100 units distributed across the pectoralis major, deltoid, and teres major. Functional improvement was sustained, and video footage taken about two months after a later infusion demonstrated near‑complete resolution.
This outcome is remarkable; literature suggests botulinum toxin yields relief in only about 20 % of peripherally induced movement disorders.
Key Questions Answered
What happened to the woman?
A 67-year-old woman developed jerks in her right arm and shoulder about six months after a shoulder fall, though she recovered from other injuries without such complications.
Why did doctors call it task-specific?
Miming the lipstick motion in the identical arm position did not trigger the jerks. Only the real action did.
What is a peripherally induced movement disorder?
An abnormal movement that develops after injury to a body part outside the brain and spinal cord. It is rare, and how it arises is debated.
What did tests show?
Muscle recordings showed rhythmic bursts averaging about five per second and lasting about 78 milliseconds, which appeared during the lipstick action. Brain and neck MRIs showed no definitive cause.
How was she treated?
Botulinum toxin injections were administered approximately every five months, providing lasting functional improvement.
Do shoulder injuries usually cause this?
No; the condition is uncommon, and most individuals recover fully from shoulder injuries without experiencing task‑specific movements.
