1.Motion-Preserving Navigated Primary Internal Fixation of Unstable C1 Fractures
Shanmuganathan RAJASEKARAN ; Dilip Chand Raja SOUNDARARAJAN ; Ajoy Prasad SHETTY ; Rishi Mugesh KANNA
Asian Spine Journal 2020;14(4):466-474
Methods:
The patients were positioned in a prone position, and cranial traction was applied using Mayfield tongs to restore the C0–C2 height and obtain a reduction in the displaced fracture fragments. An intraoperative, CT-based navigation system was used to enable the optimal placement of C1 screws. A transverse rod was then placed connecting the two screws, and controlled compression was applied across the fixation. The patients were prospectively evaluated in terms of their clinical, functional, and radiological outcomes, with a minimal follow-up of 2 years.
Results:
A total of 10 screws were placed in five patients, with a mean follow-up of 40.8 months. The mean duration of surgery was 77±13.96 minutes, and the average blood loss was 84.4±8.04 mL. The mean combined lateral mass dislocation at presentation was 14.6±1.34 mm and following surgery, it was 5.2±1.64 mm, with a correction of 9.4±2.3 mm (p <0.001). The follow-up CT showed excellent placement of screws and sound healing. There were no complications and instances of AA instability. The clinical range of movement at 2 years in degrees was as follows: rotation to the right (73.6°±9.09°), rotation to the left (71.6°±5.59°), flexion (35.4°±4.5°), extension (43.8°±8.19°), and lateral bending on the right (28.4°±10.45°) and left (24.8°±11.77°). Significant improvement was observed in the functional Neck Disability Index from 78±4.4 to 1.6±1.6. All patients returned to their occupation within 3 months.
Conclusions
Successful C1 reduction and fixation allows a motion-preserving option in unstable atlas fractures. CT navigation permits accurate and adequate monosegmental fixation with excellent clinical and radiological outcomes, and all patients in this study returned to their preoperative functional status.
2.Novel Biomarkers of Health and Degeneration in Human Intervertebral Discs: In-depth Proteomic Analysis of Collagen Framework of Fetal, Healthy, Scoliotic, Degenerate, and Herniated Discs
Shanmuganathan RAJASEKARAN ; Dilip Chand Raja SOUNDARARAJAN ; Sharon Miracle NAYAGAM ; Chitraa TANGAVEL ; Muthuraja RAVEENDRAN ; Sri Vijay Anand K S ; Ajoy Prasad SHETTY ; Rishi Mugesh KANNA
Asian Spine Journal 2023;17(1):17-29
Methods:
Forty NP tissues were snap-frozen in liquid nitrogen (–196°C) immediately before being subjected to proteomic and bioinformatic analyses from five different disk phenotypes (eight each).
Results:
Tandem mass spectrometric analysis revealed a total of 1,050 proteins in FDs, 1,809 in ND, 1,487 in SD, 1,859 in DH, and 1,538 in the DD group. Of 28 major collagens reported in the human body, this study identified 24 different collagens with 34 subtypes in NP. Fibril-forming collagens (COL-1, 2, and 11A1) and fibril-associated collagens with interrupted triple helices (COL-9A1, 12A1, and 14A1) were abundantly expressed in FDs, representing their role in the development of NP. Multiplexin (COL-15), a hybrid proteoglycan–collagen molecule, was discovered only in FDs. Degeneration was associated with COL2A1 downregulation and COL-10A1 upregulation.
Conclusions
COL10 was discovered to be a new biomarker for disk degeneration. Besides COL-1 and 2, other important COLs (6, 9, 11, 12, 14, 15) with anabolic potential and abundant expression in the fetal phenotype could be investigated for tissue engineering and novel DDD therapy.
3.Proteomic Signature of Nucleus Pulposus in Fetal Intervertebral Disc
Shanmuganathan RAJASEKARAN ; Dilip Chand Raja SOUNDARARAJAN ; Chitraa TANGAVEL ; Sri Vijay Anand K. S. ; Sharon Miracle NAYAGAM ; Monica Steffi MATCHADO ; Raveendran MUTHURAJAN ; Ajoy Prasad SHETTY ; Rishi Mugesh KANNA ; K. DHARMALINGAM
Asian Spine Journal 2020;14(4):409-420
Methods:
IVDs of nine fetal specimens obtained from medical abortions were used to dissect out the annulus fibrosus and nucleus pulposus under sterile operating conditions. Dissected tissues were transferred to sterile Cryovials and snap frozen in liquid nitrogen before transporting to the research laboratory for protein extraction and further liquid chromatography tandem mass spectrometry (LC-MS/ MS) analysis. Collected data were further analyzed using Gene Functional Classification Tool in DAVID and STRING databases.
Results:
A total of 1,316 proteins were identified through LC-MS/MS analysis of nine fetal IVD tissues. Approximately 247 proteins present in at least four fetal discs were subjected to further bioinformatic analysis. The following 10 clusters of proteins were identified: collagens, ribosomal proteins, small leucine-rich proteins, matrilin and thrombospondin, annexins, protein disulfide isomerase family proteins and peroxiredoxins, tubulins, histones, hemoglobin, and prolyl 4-hydroxylase family proteins.
Conclusions
This study provides fundamental information on the proteome networks involved in the growth and development of healthy fetal discs in humans. Systematic cataloging of proteins involved in various structural and regulatory processes has been performed. Proteins expressed most abundantly (collagen type XIV alpha 1 chain, biglycan, matrilin 1, and thrombospondin 1) in their respective clusters also elucidate the possibility of utilizing these proteins for potential regenerative therapies.