A patient involved in a road traffic accident presents with quadriparesis, sphincter disturbance, sensory level up to the upper border of sternum and a respiratory rate of 35/minute. The likely level of lesion is :

Answer is B (C4-C5): Presence of quadriparesis, sensory level up to the upper border of sternum together with an increased respiratory rate suggests a lesion of cervical spine at C4-C5 level Localization of lesion to cervical level C3-C4 The level of lesion in the above presentation can be localized to Cervical C4-C5 segments with the help of clues provided in the form of motor involvement (quadriparesis), sensory level and the affection of respiratory function. Quadriparesis (Motor level) Presence of quadriparesis (affection of all four limbs) suggests that the lesion is located in the cervical spine (The lesion may be located either at C1-C2 or C4-C5) Lesions of thoracic spine (T1-T2 or T3-T4) will only affect the two lower limbs and produce paraparesis or paraplegia, but not quadriparesis Sensory level C4 dermatome covers the area just below the clavicle Sensory loss up to the upper border of sternum is consistent with a cervical lesion at C4 level (refer figure) Lesion at CI -C2 is unlikely as this would cause complete loss of sensation below the head(C1) or below the Occiput(C2) The C2 dermatome covers the occiput and the top pa of the neck. The C3 dermatome covers the lower pa of the neck to the clavicle The C4 dermatome covers the area just below the Respiratory Rate Lesion at C4-05 level is consistent with preserved respiratory function and an increased respiratory rate `Injuries at C4 level may present with adequate function of the diaphragm secondary to innervations from a preserved C3 segment. The respiratory rate is increased and the patient compensates by using auxiliary muscles like sternomastoid, trapezius and platysma '- 'The Cervical Spine' by Clarke (Lippincott-Williams) 4th/ 181 Lesions above C3( C1-C2) result in a total loss of ventilatory function and requires immediate respiratory suppo / mechanical ventilation