Critical Review of the State-of-the-Art on Lumbar Percutaneous Cement Discoplasty

Abstract

Interbody fusion is the gold standard surgery to treat lumbar disc degeneration disease but can be a high-risk procedure in elderly and polymorbid patients. Percutaneous Cement Discoplasty (PCD) is a minimally invasive technique developed to treat advanced stage of disc degeneration exhibiting a vacuum phenomenon. A patient-specific stand-alone spacer is created by filling the disc with polymethylmethacrylate cement, allowing to recover the disc height and improve the patient’s conditions. As it has recently been introduced in the lumbar spine, this review aims to present a transversal state-of-the-art of the surgery from its clinical practice and outcome to biomechanical and engineering topics. The literature was searched across multiple databases using predefined keywords over no limited period of time. Papers about vertebroplasty were excluded. Among 466 identified papers, the relevant ones included twelve clinical papers reporting the variations of the surgical technique, follow-up and complications, four papers reporting biomechanical ex vivo and numerical tests, and four letters related to published clinical papers. Papers presenting the operative practice are reported, as well as follow-ups up to four years. The papers found, consistently reported that PCD significantly improved the clinical status of the patients and maintained it after two years. Spine alignment was impacted by PCD: the sacral slope was significantly reduced, and disc height increased. The foramen opening correlated to the volume of injected cement. Substitutes to the acrylic cement exhibited better osteointegration and mechanical properties closer to bone tissue. Finally, limitations and risks of the surgery are discussed as well as potential improvements such as the development of new filling materials with better mechanical properties and biological integration or the investigation of the inner disc.

Assessment of foraminal decompression following discoplasty using a combination of ex vivo testing and numerical tools

“…The volume of cement injected in vitro (Fig. 6 ) was 2–9 ml, in the range of 3–10 ml clinically reported 2 . Finally, larger volumes of cement were associated with larger increase of the foramen space in extension only, due to the direct involvement of cement for this direction of motion.…”

“…During surgery, the degenerated disc is filled with injected acrylic bone cement to create a spacer between the vertebrae and indirectly decompress the nerves by restoring the disc height and the neuroforaminal space 1 . Postoperatively, PCD significantly decreased pain level in patients of various studies and improved their quality of life 2 . With only 4% of cement leakages as most common complication, PCD is a promising alternative minimally invasive treatment to interbody fusion for polymorbid patients.…”

Association between Modic changes and intervertebral vacuum phenomenon severity in patients undergoing percutaneous cement discoplasty

“…IVP has recently gained weight as a contributing factor to LBP, this imaging finding is considered a sign of advanced disc degeneration and has been the benchmark for the development of percutaneous cement discoplasty (PCD) (11), a relatively new technique that has emerged as an alternative minimally invasive procedure, to treat low back pain (LPB) by injecting polymethylmethacrylate (PMMA) into the vacuum disc to stabilize the disc unit. This procedure has been shown to decrease LBP and is considered a safe technique, especially among elderly patients in whom standard fusion is associated with a higher risk of complications due to patients' co-morbidities (12)(13)(14).…”

Biomechanical consequences of cement discoplasty: An in vitro study on thoraco-lumbar human spines

“…Another study compared the effect of friction at the cement-endplate interface on the disc tissue stress (Li et al, 2022). If PCD appeared efficient to relieve patient's pain, biomechanics of the human spine following the surgery remain largely unknown and require supplementary investigations (Techens et al, 2022). Combining more experimental and numerical studies would help expanding the research on PCD and improve the surgical technique.This study aims at investigating the consequences of percutaneous cement discoplasty on the biomechanics of the human spine with respect to the pre-operative degenerated condition.…”