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

First, see the sensory distribution of the lower neck & upper trunk. C2 dermatome →Occiput & top part of the neck. C3 dermatome → Lower part of neck upto the clavicle. C4 dermatone →Area just below the clavicle (Area which coincides with the upper border of the sternum) Motor supply of upper-limb is C5_8 T, Motor supply of diaphragm (Phrenic nerve) is C3_5 Now the findings of the patient in question:- Li Patient has quadriparesis (i.e. weakness of upper as well lower limbs) →p lesion should be above or at C5 dermatome (upper limb has motor supply C5_8 T1) Sensory loss up to the upper border of sternum → C4 area Respiratory rate 35/minute → preservation of respiratory function with increased rate. Lesion at C4_5 level is consistent with preserved respiratory function and increased respiratory rate. So, the lesion is at C4_5 level.