The following is a list of complications of performing a lumbar puncture:

• Headache- can occur in up to 24% of patients. With the atraumatic pencil point needle the incidence can be reduced to 12%. Use of a smaller gauge needle also reduces the risk for post-LP headache.
• Local pain and nerve root irritation resulting in radicular pain and dysesthesia- usually self-limited.
• Brain herniation- risk reduced by careful patient selection and evaluation with neuroimaging if there are signs of increased intracranial pressure.
• Local infection-prevented with good aseptic techniques.
• Local bleeding- minimized by using small bore needle and correcting any coagulation defects prior to the LP.
• Implantation of epidermis with resulting tumor- this can occur when a non-styleted needle is used.
• Aggravation of spinal block- if there is a mass then a LP can worsen the cord compression and cause acute deterioration.
• Epidural abscess or hematoma- rare.
• Diskitis- rare.
• Osteomyelitis- rare.
• Complications of therapeutic injections- chemical meningitis, chronic adhesive arachnoiditis.
• Spinal cord damage- when the spinal cord is at an abnormally low vertebral level or if the LP is done at an interspace that is at the level of the spinal cord.
• False laboratory data- false-positive gram stain or culture, failure to obtain or record CSF opening pressure correctly, etc.