Weakness

Info

🌱 來自: Huppert’s Notes

Weakness🚧 施工中

Weakness

•   Step 1: Delineate neurologic versus non-neurologic causes of weakness and take a detailed history

-   Non-neurologic causes of weakness:

•   Generalized weakness/deconditioning from prolonged bedrest or systemic illness

•   Asthenia (motor impairment due to pain or joint dysfunction)

•   Functional/psychogenic weakness – diagnosis of exclusion!

-   History of present illness:

•   Be specific! Describe the weakness; are there specific tasks the patient has difficulty performing? Are they limited by fatigue, shortness of breath, joint pain, etc.?

•   Tempo: Hyperacute, acute, subacute, chronic, episodic, fatigable?

•   Distribution: Generalized, proximal vs. distal, unilateral vs bilateral, symmetric vs. asymmetric?

•   Progression over time: Have symptoms remained localized? Or have they spread over time?

•   Sensory involvement: Numbness, paresthesia, allodynia

•   Autonomic symptoms: Orthostasis, palpitations, bowel/bladder dysfunction, pupil abnormalities

•   Associated symptoms: Recent fever, URI, gastroenteritis, or vaccinations (rarely trigger Guillain-Barré), neck/back pain, spine trauma, tenderness, breathing difficulties

-   Review other history/comorbidities:

•   Medications: Perform a complete medication reconciliation. In particular, ask about medications which may contribute to weakness (e.g., statins, colchicine)

•   Past medical history: Certain medical conditions can contribute to weakness (e.g., DM, thyroid disease, HIV, syphilis, B12 deficiency)

•   Social history: Ask about alcohol use, recreational drug use

•   Family history: Ask about family history of neuromuscular disorders, such as myopathy, ALS, multiple sclerosis

•   Step 2: Localize the lesion. See Table 12.2 and the following information about CNS and PNS causes of weakness

TABLE 12.2 • Upper Motor Neuron (UMN) vs. Lower Motor Neuron (LMN) Clinical Findings

CNS causes of weakness

•   Brain: Suspect if UMN signs (hyperreflexia, spasticity, distal>proximal weakness in pyramidal distribution, +Babinski sign), cortical signs (language deficits, neglect, visual field cut), etc.

•   Spinal Cord: Suspect if UMN signs that are symmetric or asymmetric without facial involvement

PNS causes of weakness

•   Motor neuron (anterior horn cell): LMN signs (+/– UMN signs if ALS), patchy weakness, no sensory involvement

•   Peripheral nerve: LMN signs (hypo- or areflexia, decreased tone, atrophy, fasciculations), symmetric or asymmetric, axonal neuropathy typically length-dependent, demyelinating neuropathy patchy

•   Neuromuscular junction: LMN, usually symmetric, proximal muscle weakness, check for bulbar signs/symptoms (“D” symptoms – dysphagia, diplopia, dysarthria); extraocular movement restriction, ptosis, and shortness of breath (especially orthopnea and with bending over)

•   Muscle (myopathy): LMN, often symmetric, tends to be proximal (axial muscles, deltoids, hip flexors) > distal (decreased grip strength, weakness of wrist flexion/extension)