Pain Flashcards
What are the names of receptors which sense pain?
Nociceptor
What substances can sensitise nociceptors?
Leukotrienes Substance P Noradrenaline Neurokinin A CRGP Nitric oxide Reactiev oxygen species Cytokines Prostaglandins
What types of fibres transmit painful stimuli?
A-delta and C fibres
Which ascending tract does painful stimuli follow to the brain?
Spinothalamic tract
Describe the gate control theory of pain
In the absence of input from C fibres, tonically active inhibitory interneurons suppress the pain pathway but with strong pain the C fibres can override this inhibitory neuron to allow a pain signal to be sent to the brain, however, pain can also be modulated by simultaneous somatosensory input
Describe the phenomenon of referred pain
The sensation of pain is experienced ay a site other than the injured or disease tissue. It occurs because both visceral and somatic afferents converge on the same neurons in the spinal cord. So input from the viscera may be ‘refer’ to the somatic source
What is hyperalgesia?
Increased sensitivity to painful simtuli
Describe the type of pain that occurs in non-specific low back pain
Characterised by tension, pain and stiffness particularly in the morning
usually short lived and self-limiting
usually varies with time and physical activity
How would non-specific low back pain, with no red flags, be managed?
Giving general information, education and advice
Analgesia - usually paracetamol and avoiding NSAIDs where possible
Patients advised to stay active and complete back exercises
What factors may contribute to the development and maintenance of chronic pain and disability (i.e. yellow flags)?
Belief that pain is harmful and disabling sickness behaviours i.e. extended rest social withdrawal problems at work emotional problems inappropriate expectations of treatment
Prolapse of the intervertebral disc involves the protrusion of the nucleus pulpous towards the intervertebral foramen. This is usually an anterior protrusion. T/F?
False- it is usually posterior
What red flag symptoms may indicate a more serious cause of back pain?
Systemic ailments (fever, night sweats)
history of malignancy or IV drug use
profound or progressive neurological deficit
sphincter disturbance (bladder or bowels)
trauma
pain refractory to medicines
Age <20 or >50
Prolonged corticosteroid drug use
Presence of contusion of abrasions over the spine
What more serious cause of back pain does IV drug use or immunocompromised states put you at risk of?
Osteomyelitis
If, in a patient presenting with back pain, you were concerned about the possibility of malignancy or infection what lab tests would you run?
FBC
Erythrocyte sedimentation rate
C-recative protein
Blood cultures
A patient should receive an X-Ray If symptoms of low back pain continue after how many weeks of conservative treatment?
6-8 weeks
How long is the spinal cord?
42-45cm
What is pain?
An unpleasant sensory and emotional experience associated with actual or potential tissue damage
What catabolic stress responses are associated with pain?
Anxiety, depression, sleep impairment, increased blood pressure and heart rate, nausea, vomiting, ileum, urinary retention, uterine inhibition, restlessness, immobility, hyperventilation and cough inhibition
How does pain affect the hormones cortisone, glucagon and growth hormone?
Pain increases these hormones
How does pain affect the hormones insulin and testosterone?
Pain decreases these hormones
Through what type of fibres is physiological painful stimulation transmitted?
A-delta fibres
Through what type of fibres is pathological painful stimulation transmitted?
C fibres
C fibres transmit information faster than A-delta fibres. T/F?
False - the opposite is true
Physiological pain can be described as sharp, short and localised. How is pathological pain described?
Dull, diffuse, prolonged, produces spasm and guarding
