Upper limb neurological examination

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search
Upper limb neurological examination
Medical diagnostics
Nerves of the left upper extremity.gif
Distribution of nerves in the upper limb
Purpose assess the motor and sensory neurons which supply the upper limbs

An upper limb neurological examination is part of the neurological examination, and is used to assess the motor and sensory neurons which supply the upper limbs. This assessment helps to detect any impairment of the nervous system, being used both as a screening and an investigative tool. The examination findings when combined with a detailed history of a patient, can help a doctor reach a specific or differential diagnosis. This would enable the doctor to commence treatment if a specific diagnosis has been made, or order further investigations if there are differential diagnoses.

Structure of examination[edit]

The examination is performed in sequence:[1]

  1. General inspection
  2. Muscle tone
  3. Power
  4. Reflexes
  5. Coordination
  6. Sensation

General inspection[edit]

The upper body is exposed and a general observation is made from the end of the bed. Signs of neurological disease include:[2]

Muscle tone[edit]

The hand is grasped like a handshake and the arm is moved in various directions to determine the tone.[1] The tone is the baseline contractions of the muscles at rest. The tone may be normal or abnormal which would indicate an underlying pathology. The tone could be lower than normal (floppy) or it could be higher (stiff or rigid).

Power[edit]

The strength of the muscles are tested in different positions against resistance.[1]

Reflexes[edit]

There are 3 reflexes in the upper arm that are tested.[1][2] These are the biceps, triceps and supinator reflex. The reflexes may be abnormally brisk or absent. In the latter, the reflex could be elicited through reinforcement by asking the patient to clench their jaw.[2]

Coordination[edit]

Three separate aspects of coordination are tested:[1]

Finger-nose test[edit]

This maneuver tests for dysmetria.

Examiner holds his hand in front of the patient, who is then asked to repeatedly touch their index finger to their nose and examiners finger. The distance between the examiner's hand and patient's nose should be larger than the forearm length of patient, so that the patient need to move both his shoulder joint and elbow joint during the test instead of just moving the elbow joint.

Healthy individual could touch accurately on the nose and examiner's hand with ease, while dysmetria patient will constantly miss the nose and the hand.

Rapid pronation-supination[edit]

This maneuver tests for dysdiadochokinesia.

The patient is asked to tap the palm of one hand with the fingers of the other, then rapidly turn over the fingers and tap the palm with the back of them, repeatedly. The patient is asked to perform the clapping as quickly as he could.

Dydiadochokinesia patient will be impaired in the rate of alternation, the completeness of the sequence, and in the variation in amplitude involving both motor coordination and sequencing.[3][4]

Pronator drift[edit]

The arms are outstretched and patient is instructed to close their eyes. If the hands do not move, it is normal.

Sensation[edit]

The five aspects of sensation are tested:

  1. Light touch - tested using cotton wool
  2. Pain - tested with a neurological pin
  3. Proprioception (sense of joint position) - tested by moving the thumb while the patients eyes are closed. Patient is then asked whether the thumb is moved up or down.
  4. Vibration - tested with a 128 Hz tuning fork placed at the first joint of the thumb
  5. Temperature - tested with hot and cold test tubes. Alternatively the cold tuning fork used for vibration sense, could be used.

References[edit]

  1. ^ a b c d e Longmore, Murray; B. Wilkinson, Ian; Baldwin, Andrew; Wallin, Elizabeth (2014). Oxford Handbook of Clinical Medicine. Oxford University Press. pp. 72–73. ISBN 9780199609628. 
  2. ^ a b c Cox, Niall; A. Roper, T (2009). Clinical Skills. Oxford University Press. pp. 201–217. ISBN 9780192628749. 
  3. ^ Deshmukh, A; Rosenbloom, MJ; Pfefferbaum, A; Sullivan EV (2002). "Clinical signs of cerebellar dysfunction in schizophrenia, alcoholism, and their comorbidity". Schizophr. Res. 57 (2-3): 281–291. doi:10.1016/s0920-9964(01)00300-0. PMID 12223260. 
  4. ^ Diener, HC; Dichgans, J (1992). "Pathophysiology of Cerebellar Ataxia". Movement Disorders. 7 (2): 95–109. doi:10.1002/mds.870070202. PMID 1584245. 

External links[edit]