Limb weaknesses etc Flashcards
causes of slowly progressinge proximal weakness
Inflammatory myopathies: dermatomyositis, inclusion body myositis, polymyositis
Muscular dystrophies: Duchenne’s (X-linked disorder, affects muscle membrane protein dystrophin). Thyroid myopathies, toxic and iatrogenic myopathies (statin-induced, alcohol related and steroid induced).
Myasthenia gravis: autoimmune isease, distinguishing feature – fatiguability with exercise, Ach receptor-binding antibodies in the blood.
Amyotrophic lateral sclerosis.
Proximal weakness with prominent muscle atrophy suggests what ddx?
muscular dystrophy, cachectic myopathy, MND
do neuromuscular junction disorders affect muscle bulk?
No
lesions wehere produce spasticity?
in the pyramidal system. clasp knife
lesions where produce rigidity?
in the extrapyramidal system. increase in tone is independent of velocity nad direction of movement
flacidity occurs when lesions are where>?
PNS lesion or hyperacute CNS (Stroke, spinal shock)
causes of rapidly progressing acute weakness
Guillain Barre syndrome
Myasthenic crisis
Brainstem catastrophe
Botulism
Causes of sensory polyneuropathy:
Diabetes
B12 deficiency
Monoclonal gammopathy – Igs formed from a single circulating clone of plasma cells. Associated with multiple myeloma. Neuropaites associated tih monoclonal gammopathy:
Length-dependent axonal polyneuropathy
POEMS (polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, skin changes)
Anti-MAG (myelin-assocaited glycoprotein)
Amyloidosis
Vasculitis (but ususually causes MM) EtOH CMT HIV Thyroid dysfunction
Iatrogenic: chemotherapy (cisplatin), amiodarone, chloroquine, colchicines, metronidazole, phenytoin
Idiopathic
screening panels for common causes of sensory polyneuropa
HBA1c, and OGTT TSH B12 levels (+homocysteine + methylmalonic acid if B12 low or borderline) Serum protein electrophoresis, urine protein electrophoresis Blood urea, nitrogen, creatinineALT, AST HIV antibodies ESR Antinuclear antibody
What is lateral medullary syndrome?
Also known as wallenberg’s syndrome; it is caused by a brainstem stroke in the territory of the vertebral or posterior cerebellar artery
Clinical features:
Ipsilateral signs: Horner’s syndrome, nsystagmus, facial sensory impairment, ataxia, diplopia
Contralateral signs: pain and temperature loss over opposite arm and trunk (spinothalamic tract)
findings of cerebellar synd
General
Intention tremor
Neurological
Ataxic gait, truncal ataxia, hypotonia, pendular reflexes, dysmetria, dysdiadochokinesis, nustagmus, slurred speech, heel-shin ataxia
Extras
Cause: fractures of multiple sclerosis (spastic parapareis, sensory disturbance, INO)
Features of chronic alcoholism (liver disease)
Friedreich’s ataxia (young patient, wheelchair/walking aids, pes cavus, kyphoscoliosis, absent ankle jerks with up-going plantars)
causes of cerbellar syndrome
Multiple sclerosis Alcoholic cerebellar degeneration Posterior fossa space-occupying lesion Brainstem vascular elsion Inherited ataxias (Friedreich’s) Paraneoplastic syndromes Drugs (phenytoin)
how to differentiate the site of cerebellar
The cerebellum is divided into midline vermis nad two cerebellar hemispheres
Disease of the vermis leads to truncal ataxia and ataxic gait
Disease of hemisphere cuases ipsilateral dysmetria, dysdiadochokinesis, intention tremor, fast-beat nystagmus towards the lesion
MS (demyelination) cuases a global deficit.
What is Friedreich’s ataxia:
Autosomal recessive, trinucelotide repeat on chromosome 9/
Degeneration of the spinocerebellar tract causes cerebellar signs
Corticospinal tract damage and peripheral nerve degeneration lead to absent ankle jerks with extensor plantars
Pes cavus, scoliosis and diabetes are common features, others include cardiomyopathy, cataracts and sensorineural deafness.
what is myotonic dystrophy
Autosomal dominant, trinucleotide repeat disorder showing genetic anticipation (expansion of an unstable CTG repeat in the myotonic protein kinase gene). Gene located on chr19
findings in myotonic dystrophy
General
Myopathic facies – elongated face, wasting of SCM group, speech (ansal or dysarthric), pinprick marks on fingertips from BM testing
Face
Bilateral ptosis, wasting of facial muscles with hollowing temporal bones and cheeks, frontal baldness, smooth forehead, cataracts
Hands
Generalised weakness and wasting of upper limbs
associated complicaitons in myotonic dytrophy
Cardiac: DCM, arrhythmias
Resp: risk of aspiration due to muscle weakness
GI: dysphagia, delayed gastric emptying
Endocrine: risk of diabetes, thyroid dysfunction
Reproductive: testicular atrophy, infertility
Other: cataracts
Bell#s palsy incidence and cause
Common (1:5000) acute facial palsy, ?due to viral infection (Herpes simplex) causing swelling of the facial nerve and compression in the facial canal. Lyme disease and HIV seroconversion may cause that.
bells palsy features
- Profound unilateral facial weakness.
- Develops over 24-48h
- Pain behind the ear on onset
- Difficulty closing the eye
- Slurred speech, losing food from the corner of the mouth
- Reduced taste
- Hyperacusis
bell’s phenomenon
upward conjugate eye movement when eyes are closed.
spastic paraparesis ddx??
Always think about acute spinal cord compression: tell that you want to ask about bladder and bowel symptoms, perform a PR exam.
Most likely malignancy in spinal cord: metastasis from lung, breast, prostate cancer. Multiple myeloma also likely. Causes:
Compression – tumour, osteoarthritis, trauma,fracture, central disc prolapsed
Transverse myelitis: MS, inflammatory, vascular disorders
Degenerative
Infective: HIIV
Others: cerebral palsy, subacute combined degeneration of the cord.
CERVICAL SPONDYLOSIS definition
Progressive degenerative process affecting cervical vertebral bodies and intervertebral discs → compression of the spinal cord, nerve roots.
cervical spondylosis epidemiology + Aetiology
Ae: osteoarthritic degeneration ov the vertebrae produces osteophytes which protrude on the exit foramina and spinal canal and compress structures.
Epidemiology: mean age 48 years. Incidence 100/100000 (M:F=3:2)
Hx in cervical spondylosi
- neck pain or stiffness, arm pain (stabbing or dull)
- Parasthesia, weakness, clumsiness in hands
- Weak and stiff legs, gait disturbance
- Atypical chest, breast or facial pain
examination in cervical spondylosi
- Atrophy of forearm or hand muscles
- Segmental muscle weakness according to nerve distribution
- Sensory loss mainly for pain and temperature
- Lhermitte’s sign.
features of gait:
Posture: straight or hunched over? Hyperextended at the waist and neck?
Base: stand with their feet close together or abnormally wide apart?
Initiation: is there delay?
Stride length: normal or shortened?
Stride appearance: do feet elevate appropriately? Barely clear the ground? Land normally? Shuffle or slap ground? Posturing of the arms?
Stability?
Turns: >2 steps to turn 180⁰?
Gowers’ sign
needs to use arms to get from seated position to standing (proximal muscle weakness)
Trendelenburg sign:
weakness of hip stabilisation – the trunk will sink to the side of elevated leg (proximal weakness)
toe walking
gastrocnemius and soleus (S1 + tibial nerve
heel walking
tibialis anterior (peroneal nerve, L4,5 roots).
tandem gait and romberg’s test
usually to detect ataxic gait. + Romeberg’s sign (cerebellar or dorsal column lesions)
