Failed Back Surgery Syndrome¶

Definition¶

Failed back surgery syndrome (FBSS) is persistent or recurrent pain after spinal surgery. It is not a single diagnosis but a clinical syndrome with multiple potential causes, requiring systematic imaging evaluation to identify the specific etiology.

Causes¶

Recurrent/Residual Pathology¶

Recurrent disc herniation at the operative level
Residual disc fragment (inadequate decompression)
Residual or recurrent spinal stenosis

Post-Surgical Complications¶

Epidural fibrosis (scar tissue) compressing nerve roots
Post-surgical instability or spondylolisthesis
Adjacent segment disease
Pseudarthrosis (nonunion)
Hardware failure (loosening, breakage, malposition)
Recurrent herniation at a new level

Non-Surgical Causes¶

Sacroiliac joint dysfunction
Facet arthropathy
Myofascial pain
Arachnoiditis (clumping of cauda equina nerve roots)
Psychological factors

Imaging Approach¶

Radiography — Alignment, hardware position, instability (flexion-extension)
MRI with contrast — Distinguish scar from recurrent disc, evaluate for stenosis, cord/root compression, arachnoiditis
CT — Hardware assessment, fusion status, bony stenosis

Clinical Pearl

A systematic approach to FBSS imaging: (1) Is the surgery adequate? — check for residual stenosis or disc fragment. (2) Is there a new problem? — recurrent herniation, adjacent segment disease, instability. (3) Is there a complication? — pseudarthrosis, hardware failure, epidural scar. (4) Is the pain source non-spinal? — SI joint, facet, myofascial.

Key Points¶

FBSS is a syndrome, not a single diagnosis — systematic evaluation is essential
Post-contrast MRI is the key study for soft tissue evaluation
Recurrent disc vs scar is the most common diagnostic question
Always evaluate hardware position, fusion status, and adjacent segments
Non-surgical pain generators should be considered

References¶

Orhurhu VJ, Chu R, Gill J. Failed Back Surgery Syndrome. In: StatPearls. Treasure Island (FL): StatPearls Publishing; 2023. Available from: https://www.ncbi.nlm.nih.gov/books/NBK539777/
Witkam RL, Buckens CF, van Goethem JWM, Vissers KCP, Henssen DJHA. The current role and future directions of imaging in failed back surgery syndrome patients: an educational review. Insights Imaging. 2022;13:117. Available from: https://pmc.ncbi.nlm.nih.gov/articles/PMC9287525/
Sebaaly A, Lahoud MJ, Rizkallah M, Kreichati G, Kharrat K. Etiology, Evaluation, and Treatment of Failed Back Surgery Syndrome. Asian Spine J. 2018;12(3):574-585. Available from: https://pmc.ncbi.nlm.nih.gov/articles/PMC6002183/
Baber Z, Erdek MA. Failed back surgery syndrome: current perspectives. J Pain Res. 2016;9:979-987. Available from: https://pmc.ncbi.nlm.nih.gov/articles/PMC5106227/
Sen KK, Singh A. Magnetic Resonance Imaging in Failed Back Surgery Syndrome. Med J Armed Forces India. 1999;55(2):133-138. Available from: https://pmc.ncbi.nlm.nih.gov/articles/PMC5531858/
Expert Panel on Neurological Imaging; Hutchins TA, Peckham M, Shah LM, Parsons MS, et al. ACR Appropriateness Criteria® Low Back Pain: 2021 Update. J Am Coll Radiol. 2021;18(11S):S361-S379. Available from: https://www.jacr.org/article/S1546-1440(21)00701-8/fulltext
Failed back surgery syndrome. Radiopaedia.org. Available from: https://radiopaedia.org/cases/failed-back-surgery-syndrome