Neuromuscular Localization
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Transcript Neuromuscular Localization
Sistem Neuromuskular
Sistem Neuromuskular
Tiga komponen utama Neuromuskular
Nerve
Neuromuscular junction
Muscle
Upper Motor Neuron
Semua neuron yang menyalurkan impuls
motorik secara langsung ke LMN atau
melalui interneuronnya, tergolong dalam
kelompok UMN. Neuron-neuron tersebut
banyak terdapat di girus presentralis
dinamakan juga korteks motorik. Melalui
aksonnya neuron korteks motorik
menghubungi motoneuron di kornu
anterior medulla spinalis.
Area Motorik
Upper motorneuron
Lower motorneuron
Lower Motor Neuron
Merupakan neuron-neuron yang
menyelurkan impuls motorik pada bagian
perjalanan terakhir (kornu anterior medula
spinalis) ke sel-sel otot skeletal.
Motor end Plate
Pada ujungnya setiap akson akan
bercabang-cabang dan setiap cabang
menghubungi membrane serabut otot.
Serabut-serabut otot setiap unit motorik
berkisar antara 10-500 serabut otot. Tiap
serabut otot memilki satu “motor end
plate”.
Ujung-ujung terminal dari akson
mengandung mitokondria dan ezim “cholin
acertyltransferase”, yang diperlukan untuk
sintesis “neurotransmitter” yang
dinamakan “acetylcholine”.
Pelepasan Acetilkolin
Nerves releasing Achetylcholine at the
neuromuscular junction (=end plate) cause
the contraction of skeletal muscle. The
functional unit of a muscle organ is the
muscle fiber (=muscle cell).
The muscle fiber contracts in an "all-ornone" fashion when stimulated by an
action potential. The action potential first
causes intracellular Ca++ release from the
sarcoplasmic reticulum and the Ca++
activates a cascade of events which
results in the movement of actin over
myosin (=sliding filament theory).
Tanda-tanda
kelumpuhan UMN :
• Hiperrefleksia
• Terdapat refleks
patologis
• Tonus otot meninggi
atau hipertonia
• Terdapat Klonus
• Tidak terdapat atrofi
otot yang lumpuh
• Refleks automatisme
spinal (-)
Tanda-tanda
kelumpuhan LMN :
• Arefleksia (hilangnya
refleks tendo)
• Tidak ada refleks
patologis
• Hilangnya tonus otot
(flacid)
• Tidak terdapat klonus
• Terdapat atrofi pada
otot yang lumpuh
Gangguan yang menyebabkan kelemahan
gerak (paralysis)
Kelainan pada otot
Periodik Paralysis
Inflamatory miopathy
Miopati karena steroid
Rabdomyolisis
Neuromuscular junction
Miastenia Gravis
Botulism
Tick paralysis
Lambert Eaton Myastenic Syndrome
Gangguan yang menyebabkan kelemahan
gerak (paralysis)
Neuropati akut
Paraneoplastik
Vaskulitis (lupus, poliarteritis)
Neuropati motorik multifokal
Poliradikulopati akut
Guillain-Barre syndrome
Lime Disease
Sindrome Cauda Equina
Penyakit Motor neuron
Poliomyelitis
Amyotropic Lateral Sclerosis (ALS)
Gangguan yang menyebabkan kelemahan
gerak (paralysis)
Medula Spinalis
Inflamasi (mielitis transversus)
Mielopati (spondilosis, hematom, infark)
Otak (Cerebrum, cerebellum)
Lesi di Pons
Lesi fokal/multifokal (infark, hematom)
Jenis Gangguan Saraf
Polyneuropathy: motor, sensory,
sensorimotor
Radiculopathy
Polyradiculopathy
Plexopathy
Mononeuropathy: isolated
multiplex
Klasifikasi kausa
Toxic
GBS, CIDP
Vasculitis
Infective
Drugs, alcohol,
organophosphates
Inflammatory/Immune
Leprosy, Lyme, HIV,
Diphtheria
Traumatic
Inherited
HMSN and HLPP
Amyloid
Metabolic
Diabetes
Vitamins: B12, B1, E
Dialysis, Liver failure
Paraneoplastic
sensory (anti-Hu)
Klasifikasi tipe kerusakan
Demyelinating
Axonal
Small fibre
Large fibre
Autonomic
Physical findings
Nerve
NMJ
Muscle
Reflexes
Usually decr.
NL or decr.
NL or decr.
Atrophy
Can be severe
Minimal
Variable
Fascic.
Sometimes
None
None
Sensory loss Sometimes
None
None
The Motor Unit
Myopathies
Motor Neurone
Disorders
Peripheral Neuropathy
Myasthenia etc
Gangguan pada saraf:
Variasi:
Cell body, axon & myelin
Fiber size: large, small
Motor, sensory, autonomic
Distribution: focal, multifocal, generalized
Course: acute, subacute, chronic, lifelong
Etiology: genetic, toxic, metabolic,
autoimmune, traumatic, vascular, infectious
Gangguan pada Saraf:
berdasarkan Lokasi
Radix
Plexus
Single nerve
Several nerves
radiculopathy
plexopathy
mononeuropathy
multiple mononeuropathy,
mononeuritis multiplex
polyneuropathy
All nerves,
length-dependent
All nerves,
polyradiculoneuropathy
not length-dependent
Radix
Segmental loss of
motor
atrophy
weakness
reflexes
sensation
Signs usually minimal; symptoms can
be severe (pain);
Usually only one limb.
Plexus
Pain
Weakness, atrophy, variable, but
usually more severe than radiculopathy
Usually restricted to one limb
Etiology:
Brachial: trauma, neoplasm, idiopathic
Lumbosacral: diabetes, neoplasm
Single nerve (mononeuropathy)
Restricted distribution
Pain, numbness or tingling,
atrophy, weakness
Etiology:
entrapment
trauma
Carpal tunnel syndrome
N.Medianus
Pain in hand,
forearm, arm
Numbness in
median distribution
Symptoms
aggravated by wrist
flexion
Ulnar neuropathy
Numbness
Atrophy of first dorsal
interosseous
Weakness
Compression at
elbow
Entrapment in cubital
tunnel
Distal injury
Radial nerve: Saturday night palsy
Weakness of wrist &
finger extensors,
brachioradialis
Pressure palsy
Trauma (humerus
fracture)
Peroneal palsy
Crossing legs
Weight loss
Hospitalization
Surgery
Several nerves (mononeuritis multiplex)
Often painful at onset
Often sudden
Deficits in the distribution of several
peripheral nerves (one at a time)
Etiology: vasculitis
All nerves: Length-dependent
(polyneuropathy)
Lower before upper extremity
Distal first (feet)
Atrophy of intrinsic foot muscles
Decreased ankle jerks
Stocking, then glove sensory loss
Distal motor and sensory findings
always much more severe than
proximal
Polyneuropathy (cont’d)
Polyneuropathy (cont’d)
Most common kind of neuropathy
Etiology
metabolic (diabetes, renal failure)
nutritional (thiamine, B12 deficiency)
toxic (heavy metals, organic solvents,
some drugs)
familial (Charcot-Marie-Tooth)
All nerves, not length-dependent
(polyradiculoneuropathy)
Both proximal and distal weakness
Variable sensory symptoms
Autonomic symptoms (pulse, blood
pressure, urination...)
Can affect respiration, swallowing
Autoimmune
Guillain-Barré Syndrome (GBS)
Merupakan penyakit Autoimmun
Definisi GBS :
Penyakit demyelinasi akut, yang terutama
mengenai susunan saraf tepi. Penyakit
inflamasi pada sistim saraf tepi mempunyai
karakteristik adanya infiltrasi limfosit dan
makrofag dengan destruksi myelin
Derajad dan lokasi kerusakan tergantung
saraf yang bermyelin: Motorik
Guillain-Barre syndrome
Progresses over days to <4 weeks
Typically ascending weakness
Reflexes lost early
Motor symptoms predominate, but can
affect sensation and autonomic function
Respiratory failure requires support
Guillain-Barre syndrome (cont’d)
Penyebab : autoimmun
Target Antigen biasanya tidak diketahui
Pada beberapa kasus: Target serangan imun
gangliosida (GM1, GQ1b)
Faktor presipitasi:
Infeksi virus (HIV, CMV, varicella zoster)
Infeksi bakteri (campylobacter jenjuni, typhoid,
paratyphoid)
Immunisasi
Sistemik (Hodgkins disease, leukemia, hipertiroidisme,
sarkoidosis)
Transplantasi organ, operasi, kehamilan
Latar belakang GBS
Epidemiologi GBS
1- 4 kasus/100.000
Paling banyak pada pria
Meningkat sesuai usia
Insidennya bervariasi sesuai musim
Gambaran klinis GBS
-
Gangguan Motorik:
paralisis yang progressif, simetris pada extremitas
bawah dan atas, bersifat asendern
dimulai dari distal ke proksimal
-
Gangguan sensibilitas: Stocking, dan glove
sensory loss (dysesthesia)
-
Gangguan otonom:
penyebab kematian
Clinical Picture of Polyneuropahty
(Valenstein, 2000)
Gambaran klinis GBS
Atypical presentations
Miller-Fisher
Syndrome
Areflexia
Ophthalmoplegia
Ataxia
diagnosis GBS
Riwayat penyakit sebelumnya atau vaksinasi
Dari pemeriksaan fisik (Physical Exam)
Laboratoratorium:
Peningkatan kadar protein pada pemeriksaan LCS dan
rendahnya jumlah sel di LCS (disosiasi sitoalbumin)
Electromyography – adanya blok konduksi saraf
KRITERIA GBS MENURUT GILROY DAN MEYER (1979)
1. Paralisis flasid simetris, difus
2. Gejala sensoris subyektif
3. Penyembuhan sempurna dalam 6 bulan
4. Disosiasi citoalbumin
5. Tanpa atau sedikit demam saat muncul paralysis
6. AL normal atau lymphositosis dengan sedikit atau tanpa
kenaikan KED.
Harus memenuhi 5 kriteria dari 6 kriteria
Pengobatan GBS
Fase akut
Supportive care : monitoring fungsi vital
(perawatn ICU)
Pemberian IV imunoglobulin (ivIg) 400 mg/kg
selama 5 hari, plasmapheresis 40-50 ml/kg
plasma exchange diberikan 4 kali seminggu
Kortikosteroid
Artificial ventilation (if necessary) paralysis
diafragma
Setelah fese akut
Program rehabilitasi, bladder training, perbaikan
ADL (activity daily living)
Summary of nerve disorders
Root
Disk, Herpes zoster
Plexus
Autoimmune, trauma,
neoplasm
Mononeuropathy
Trauma, entrapment
Multiple
mononeuropathy
Vasculitis...
Polyneuropathy Toxic, metabolic, nutritional
Polyradiculoneuropathy
Autoimmune
Neuromuscular junction
Disorders of the neuromusuclar
junction
Release of acetyl choline:
Botulism (toxin = endopeptidase targeting
various proteins mediating exocytosis)
Lambert-Eaton myasthenic syndrome
(antibodies to voltage-gated calcium channel)
Acetylcholine receptor blockade:
Myasthenia gravis (antibodies to ACh
receptor)
Myasthenia Gravis
Kelemahan yang berfluktuasi
Mata: ptosis, diplopia
Bulbar weakness: dysarthria,
dysphagia
Kelemahan otot proksimal
Kelemahan respirasi
Normal reflexes
Normal sensation
Berkaitan dg thymoma
Berkaitan dg penyakit
autoimun
Penyakit autoimun pada transmisi
neuromuskular junction yang
diakibatkan oleh antibodi yang
menyerang reseptor asetilkolin atau
melawan muscle spesific receptor
tyrosine kinase
Myasthenia gravis is a neuromuscular disease leading
to fluctuating muscle weakness and fatiguability.
It is an autoimmune disorder, in which weakness is
caused by circulating antibodies that block acetylcholine
receptors at the post-synaptic neuromuscular junction,
inhibiting the stimulative effect of the neurotransmitter
acetylcholine.
Myasthenia is treated medically with cholinesterase
inhibitors or immunosuppressants, and, in selected
cases, thymectomy.
At 200–400 cases per million it is one of the less
common autoimmune disorders.
Muscles become progressively weaker
during periods of activity and improve after
periods of rest. Muscles that control eye
and eyelid movement,
facial expression, chewing, talking, and
swallowing are especially susceptible. The
muscles that control breathing and neck
and limb movements can also be affected
Myasthenia Gravis
Terapi:
Acetyl cholinesterase inhibitors : pyridostigmin bromida 3x 60
mg
Plasmapharesis : plasma exchange
Imunoglobulin IV
Immunosupresan (kontroversi)
Steroid : mulai 12-50 mg
Azathioprine : 50 mg/hari
Cyclosporine : awal 3-4 mg/kg/hari dalam dosis terbagi
Cyclophosphamide : dosis 1-2 mg/kg/ hari
Thymectomy , indikasi:
Timoma
Generalized myastenia yang tidak terkontrol dengan
antikolinesterase (< 50 th, 6-12 bulan tidak ada remisi spontan)
Krisis Mistenia
Adalah keadaan eksaserbasi penyakit
Mistenia gravis dimana kelumpuhan
menyebabkan episode akut kegagalan
pernafasan
Terjadi pada 74% setelah 2 tahun
miastenia gravis
Krisis Mistenia
Faktor pencetus :
Infeksi, terutama infeksi saluran nafas
Pemakaian obat2an: aminoglikosid,
ciprofloksasin, klindamisin, propanolol, fenitoin
Tidak diketahui (30-40%)
Krisis Mistenia
Terapi :
Kontrol airways, dan perbaiki ventilasi (jika perlu
menggunakan ventilator)
Terapi antikolinesterase
Kortikosteroid
Plasma axchange atau IV Ig
Penyakit otot (myopathy)
Symmetrical proximal weakness
Reflexes normal (sometimes depressed)
No sensory loss
Myopathy (cont’d)
Inherited
Dystrophies
Congenital myopathies
Channelopathies
Acquired
endocrine
inflammatory, including
autoimmune
toxic (drugs...)
Inflammatory myopathies
Polymyositis
isolated
with collagen vascular
disease
Dermatomyositis
childhood
adult: association with
cancer
others
Dystrophy Musculorum
Muscular dystrophy is a genetic condition
causing muscle weakness
Dermatomyositis - Polymyositis
KRITERIA DIAGNOSIS
Kelemahan otot-otot proksimal simetris
Rash tipikal pada dermatomyositis
Peningkatan enzim otot / plasma muscle enzymes (CK, aldolase, AST),
khususnya creatine kinase
Terdapat korelasi antara beratnya kelemahan dengan peningkatan enzim
Gambaran myopati pada pemeriksaan needle EMG
Gambaran abnormalitas yang khas pada biopsi otot (nekrosis serabut otot
dan degenerasi, dengan infiltrasi sel-sel inflamasi)
Polymyositis
Polymyositis is a disease of muscle
featuring inflammation of the muscle fibers
The cause of the disease is not known
Polymyositis is slightly more common in
females. It affects all age groups, although
its onset is most common in middle
childhood and in the 20s
Weakness of muscles is the most common
symptom of polymyositis
Amyotrophic lateral sclerosis
Lou Gehrig's disease
Amyotrophic lateral sclerosis (ALS) is a
nervous system disease that attacks nerve
cells called neurons in your brain and
spinal cord
The cause of ALS is not known
Amyotrophic lateral sclerosis
The disease belongs to a group of disorders
known as motor neuron diseases, which are
characterized by the gradual degeneration and
death of motor neurons.
In ALS, both the upper motor neurons and the
lower motor neurons degenerate or die, ceasing
to send messages to muscles
At first, this causes mild muscle problems. Some
people notice
Trouble walking or running
Trouble writing
Speech problems
Multiple sclerosis
Multiple sclerosis (MS) is a nervous system disease that
affects your brain and spinal cord. It damages the myelin
sheath
No one knows what causes MS. However, viral and
autoimmune etiologies have been hypothesized. It may
be an autoimmune disease
The symptom can include :
Visual disturbances
Muscle weakness
Trouble with coordination and balance
Sensations such as numbness, prickling, or "pins and needles"
Thinking and memory problems
Key clinical features used to localize a neuromuscular disorder
Myopathy
•predilection for neck, limb girdle and proximal muscles
•occasional respiratory muscle involvement
•possible risk of myoglobulinuria
•no sensory loss
•normal tendon reflexes (early stage)
Neuromuscular junction
•cranial, limb girdle and proximal muscles
•may affect respiratory muscles
•no sensory loss
•autonomic symptoms present if pre-synaptic
•fatigueability when post-synaptic, post-exercise increase in strength when pre-synaptic
Neuropathy
•weakness and sensory signs
•may have associated autonomic signs
•may involve cranial nerves
•tendon reflexes decreased or absent
Motor neuron
•predominantly motor signs
•occasional sensory symptoms
•often asymmetric
•tendon reflexes may be increased if amyotrophic lateral sclerosis