The Role of Instrumentation in the Healing Process of Spinal Tuberculosis: An Experimental Study

Introduction: Tuberculosis is still commonly found in many developing countries. Spinal tuberculosis can cause vertebral deformity and neurological disorders. It was discovered thousands years ago and its management was aimed to eradicate infection and maintain the integrity of the vertebrae. Previously, the management of spinal TB was using drugs and external stabilization. Surgical techniques were developed afterwards to clean the infected vertebral segment. Because of the vertebral deformity remained inevitable and had impacts on neurological disorders, new paradigm had been developed by using instrumentation to stabilize the deformity of infected vertebral segment and to restore and maintain neurological function. TGF-β has a major role in angiogenesis in bone healing process. Spinal TB instrumentation uses metal devices composed of ions and particles that can interact each other so it could produce physical and chemical energy that is transmitted to the vertebrae. The energy is expected to enhance the biomolecular and biocellular activity of the body's immune cells so the healing process could be better. Methods: An experimental study was carried out on New Zealand Rabbits which were given TB H37Rv strain infection in the vertebral body. Samples were divided into five groups namely control rabbits, infected rabbits without intervention, infected rabbits treated by instrumentation, infected rabbits given anti-tuberculosis drugs and infected rabbits treated by instrumentation and given drugs. Then the cytokine levels of TGF-β were evaluated and compared. Results: The results showed a significant TGF- β level increase in infected rabbits given drugs alone and instrumentation alone compared to infected rabbits without intervention. There was a significant TGF- β increase in infected rabbits given drugs and treated by instrumentation compared to control rabbits and rabbits who received drugs only. Conclusions: Instrumentation can improve the healing process in spinal tuberculosis by increasing the body's cytokine levels.

CHANGES IN THE LUMBAR VERTEBRAL SEGMENT RELATED TO THE CAGE POSITION IN TLIF TECHNIQUE

ABSTRACT Objective: To evaluate the morphological changes on the intervertebral foramen and segmental lordosis related to the transforaminal lumbar interbody fusion (TLIF) positioning. Methods: PEEK cages were placed in the disc space (L1-S1) of a polyurethane anatomical model. Cages of different heights (8 mm, 10 mm, 12 mm and 14 mm) were positioned in the posterior, medial or anterior part of the vertebral body surface, and the intervertebral foramen and segmental lordosis heights were measured after their insertion. Results: The vertebral foramen height decreased in all positions and heights of the cages in relation to the control. The cage posterior positioning induced a smaller reduction in the vertebral foramen height. Vertebral lordosis tended to increase in relation to the control, and the greatest increase occurred with the cage posterior positioning. Conclusion: Cage positioning induces changes in the intervertebral foramen height and in the vertebral segment lordosis. Cage posterior positioning induces a smaller reduction of the intervertebral foramen height and increases the vertebral segment lordosis. Level of evidence III, Therapeutic study.

Vertebrae, Vertebral End Plates, and Disks: Concepts and Specific Pathologies

Vertebral end plates cover the osseous vertebral body. The integrity of the cartilaginous end plates is of great importance for the entire vertebral segment because the vascularized end plate provides the nutrition for the avascular disk. Yet several pathologies may occur at these end plates at the embryonic stage, in childhood to adolescence (e.g., ossification and segmentation disorders of the spine, persistent notochord, slippage of the growth plate), as well as in the mature spine of an adult (degenerative disk disease), that may impact the integrity of the cartilaginous end plate and therefore lead to severe diseases of the spine. This article reviews specific congenital, developmental, and degenerative disorders of the vertebral end plate as well as both established and newly introduced imaging techniques, such as ultrashort echo time imaging based on magnetic resonance imaging, that are suitable for imaging of the end plate.

RSA in Spine: A Review

Study Design: Systematic review of literature. Objectives: This systematic review was conducted to investigate the accuracy of radiostereometric analysis (RSA), its assessment of spinal motion and disorders, and to investigate the limitations of this technique in spine assessment. Methods: Systematic review in all current literature to invesigate the role of RSA in spine. Results: The results of this review concluded that RSA is a very powerful tool to detect small changes between 2 rigid bodies such as a vertebral segment. The technique is described for animal and human studies for cervical and lumbar spine and can be used to analyze range of motion, inducible displacement, and fusion of segments. However, there are a few disadvantages with the technique; RSA percutaneous procedure needs to be performed to implant the markers (and cannot be used preoperatively), one needs a specific knowledge to handle data and interpret the results, and is relatively time consuming and expensive. Conclusions: RSA should be looked at as a very powerful research instrument and there are many questions suitable for RSA studies.