BACKGROUND CONTEXT
Lumbar discectomies are common surgical interventions that treat radiculopathy by removing herniated and loose intervertebral disc (IVD) tissues. However, remaining IVD tissue can continue to degenerate resulting in long-term clinical problems. Little information is available on the effects of discectomy on IVD biology. Currently no treatments exist that can suspend or reverse the degeneration of the remaining IVD.
PURPOSE
To improve knowledge how discectomy procedures influence IVD physiology and to assess the potential of growth-factor treatment as an augmentation during surgery
STUDY DESIGN
To determine effects of discectomy on IVDs with and without TGFβ3 augmentation using bovine IVD organ culture.
METHODS
This study determined effects of discectomy with and without TGFβ3 injection using 1, 6, and 19 days organ culture experiments. Treated IVDs were injected with 0.2μg TGFβ3 in 20μl PBS+BSA into several locations of the discectomy site. Cell viability, gene expression, nitric-oxide release, IVD height, aggrecan degradation, and proteoglycan content were determined.
RESULTS
Discectomy significantly increased cell death, aggrecan degradation and nitric-oxide release in healthy IVDs. TGFβ3 injection treatment prevented or mitigated those effects for the 19 days culture period.
CONCLUSIONS
Discectomy procedures induced cell death, catabolism and nitric-oxide production in healthy IVDs, and we conclude that post-discectomy degeneration is likely to be associated with cell death and matrix degradation. TGFβ3 injection augmented discectomy procedures by acting to protect IVD tissues by maintaining cell viability, limiting matrix degradation and suppressing nitric-oxide. We conclude that discectomy procedures can be improved with injectable therapies at the time of surgery although further in vivo and human studies are required.