Case report
A 59-year-old female visited our hospital due to posterior head and neck pain that developed after a coccygeal procedure. She was referred to the pain clinic for EBP.
She underwent the caudal approach procedure a week ago at a local clinic due to pain in the left leg and foot. Reports about the procedure performed from the clinic were inaccessible, but following the patient’s description, a caudal epidural block was presumed to have been used. One day after the procedure, she found clear fluid leakage from the coccygeal area and started experiencing posterior headache. She received a disinfection and compressive dressing on the coccygeal area and was prescribed bed rest and pain killers from the local clinic, but her symptoms did not improve within a week.
The numerical rating scale (ranging from 0 to 10, with a score of 0 representing no pain and 10 corresponding to intractable pain) score for pain severity was 5 and the pain was frequent, throbbing, and worsened by the orthostatic position.
On physical examination, the compressive dressing looked clean except for some swelling around the sacral area, and no leakage was observed. Bedside ultrasound (US) showed subcutaneous edema and fluid collection in the swollen peri-coccygeal area (Fig1). There were no suspicious signs of meningeal irritation such as fever or neck stiffness. Laboratory examination revealed no leukocytosis and normal C-reactive protein levels.
We conducted the following treatments under suspicion of PDPH with subarachnoid-cutaneous fistula after the caudal procedure.
First, she was admitted for absolute bed rest, hydration with intravenous fluid, and was prescribed acetaminophen as a painkiller. A neurologist referred her to a pain clinic for EBP because her headache lasted for more than a week despite conventional conservative management from a local clinic. We initially did not consider EBP through the sacral hiatus as a treatment plan, because there was a possibility of infection in the presence of a fistula or repeated CSF leakage. MRI was scheduled for checking the presence of subcutaneous CSF leakage and its cause. Additionally, we decided to disinfect the wound and apply compressive dressing using an obliquely applied abdominal binder around the patient’s buttocks and the lower abdomen for better compact compression than that with the previous conventional compressive dressing, which comprised of adhesive tape and gauze.
After admission, a radiologist reported MRI, showed a low-lying conus medullaris (which reached down to the inferior border of the S2 vertebra, Fig 2) with a thickened filum terminale, an 8 × 7 cm2 sized fatty contiguous mass with a placode at the sacrococcygeal area, and interspersed fluid around the mass. (Fig 3A and B) This showed that she had a rare TCS that was now discovered late in adulthood. A surgical procedure should have been considered for TCS, but since she did not have any symptoms of the cauda equina syndrome or any other severe neurologic symptoms, except the initial symptoms of left leg and foot pain, we decided to use reinforced conservative management with an abdominal binder first for a week.
On the 3rd day of hospitalization, the headache and neck pain decreased, but reappeared after a short walk. On the 4th day, she could walk without headache and neck pain, but she could still sometimes experience mild posterior neck pain. On the 5th day, US still showed irregular and mild hypoechoic subcutaneous edema around the coccyx area and suspicious fluid collection, but its size had decreased. On the 6th day, she was discharged with an abdominal binder.
One week after discharge, she visited the pain clinic and had no complaints even without the abdominal binder.