Discitis or spinal infections account for 2-4% of bone infections. It is a condition which causes pain and discomfort in the spinal region due to infection of the vertebrae or intervertebral disc space. There are various stages of treatment based on the patient’s response to treatment. They include conservative treatment with antibiotics, bed rest, use of back braces and surgical treatment. Surgical treatment is indicated when the patient does not respond to conservative management. In recent times, minimally invasive, Full Endoscopic Debridement and Drainage (FEDD) is widely being used to treat discitis.
What is Endoscopic Debridement of Discitis?
It is a minimally invasive surgical procedure which involves thorough cleaning and removal of infected tissues and foreign material to promote healing and growth of healthy tissue in the infected area of the spine. There are different approaches of endoscopic debridement of the discitis, these are decided by the surgeon based on the location of the infection within the spine.
Indications
Spinal infections are classified into two types based on their location: Anterior and posterior. The following conditions under these categories are indicated for treatment with endoscopic debridement:
Anterior
- Discitis
- Spondylodiscitis
- Psoas abscess
- Anterior epidural abscess
Posterior
- Posterior epidural abscess
- Paraspinal abscess
In some cases patients may present with both anterior and posterior pathologies.
Procedure:
Endoscopic debridement procedure for discitis is carried out under local anaesthesia and the patient is put in prone position. A needle with a negative pressure syringe is inserted into the infected disc area under fluoroscopic guidance. It is gradually pushed deeper inside by simultaneously checking the fluoroscopy to avoid deep puncture.
The pus is drained along with thorough debridement of infected tissue and disc structure using endoscopic forceps. This is followed by examination of surrounding dura and nerve roots to ensure sufficient decompression, normal saline irrigation (beta-iodine solution may be used), and placement of Hemovac drain into the disc space. The choice of approach is determined by the surgeon, based on the location. The different approaches include:
Transforaminal approach: The transforaminal approach is further divided into two techniques: “inside-out” or “outside-in” techniques. This approach is used for debridement of disc space.
Trocar-rotating method: This approach is used to treat psoas abscess, a muscle which is located outside the disc space. This is carried out after debridement of the disc space.
Interlaminal approach: This approach is used for posterior epidural abscess.
Post-operative patient care
Administration of intravenous antibiotics is continued after surgery with placement of a hemovac drain. The patient’s condition is followed-up on a regular basis through laboratory tests and evaluation of the amount of fluid drainage from the hemovac drain. Patients are advised to be discharged if there is improvement in pain and laboratory test values. The hemovac drain can be removed if the fluid drainage is less on 10-15ml per day. Patients are prescribed oral antibiotics, advised to wear a back brace and regular follow-up continues even after discharge.
Recovery
Studies indicated that patients treated with endoscopic debridement for discitis showed significant improvement in pain within one week of the post-operative period. There were no intra-operative complications or recurrent infections for at least a period of 12 months.
Advantages of Endoscopic Debridement of Discitis
The following advantages are observed with treatment of spinal infections through endoscopic debridement:
- Minimally invasive
- Minimal surgical wound pain
- Maximum infection control
- No approach-related complications
- Faster recovery
- Higher culture rates than CT-guided biopsy
- Successful identification of infectious agent
- Lower risk of contamination during surgery
- No Morphine consumption required for pain relief
