Altug Yucekul1, Burcu Akpunarli2, Atahan Durbas3, Tais Zulemyan4, Irem Havlucu4, Gokhan Ergene5, Sahin Senay6, Pinar Yalinay Dikmen7, Sule Turgut Balci8, Ercan Karaarslan9, Yasemin Yavuz10, Caglar Yilgor1, Ahmet Alanay11. 1. Department of Orthopedics and Traumatology, Acibadem Mehmet Ali Aydinlar University School of Medicine, Istanbul, Turkey. 2. Urla State Hospital, İzmir, Turkey. 3. Acibadem Mehmet Ali Aydinlar University School of Medicine, Istanbul, Turkey. 4. Comprehensive Spine Center, Acibadem University Maslak Hospital, Istanbul, Turkey. 5. Acibadem Mehmet Ali Aydinlar University Vocational School of Health Sciences, Department of Operating Room Services, Istanbul, Turkey. 6. Acibadem Mehmet Ali Aydinlar University School of Medicine, Department of Cardiovascular Surgery, Istanbul, Turkey. 7. Acibadem Mehmet Ali Aydinlar University School of Medicine, Department of Neurology, Istanbul, Turkey. 8. Anesthesiology Service, Acibadem University Maslak Hospital, Istanbul, Turkey. 9. Acibadem Mehmet Ali Aydinlar University School of Medicine, Department of Radiology, Istanbul, Turkey. 10. Ankara University School of Medicine, Department of Biostatistics, Ankara, Turkey. 11. Department of Orthopedics and Traumatology, Acibadem Mehmet Ali Aydinlar University School of Medicine, Istanbul, Turkey. Electronic address: aalanay@gmail.com.
Abstract
BACKGROUND CONTEXT: Vertebral body tethering (VBT), a flexible compression-based growth modulation technique, was claimed to prevent disc degeneration due to its less rigid nature compared to other growth-friendly techniques. Yet, the consequences of VBT surgery on discs and facet joints have not been precisely acknowledged. PURPOSE: The purpose of this study was to determine the changes in the intermediate and adjacent levels at least 2 years after surgery. STUDY DESIGN/ SETTING: Prospectively-followed consecutive patient cohort PATIENT SAMPLE: Adolescent idiopathic scoliosis patients who underwent thoracoscopic VBT between 2014 and 2017 were included. OUTCOME MEASURES: Degeneration of the intervertebral discs using the Pfirrmann classification; Degeneration of facet joints using a scale of 0 to 3. METHODS: Demographic, perioperative, clinical, radiographic data were collected. Skeletal maturity and height gain were assessed in every follow-up. Overcorrection, tether breakage, mechanical and pulmonary complications as well as readmission and reoperations were recorded. MRIs taken before surgery and at a minimum of 2 years follow-up were evaluated for degeneration at the intermediate and adjacent segment intervertebral discs and facet joints by a blinded senior radiologist and compared. RESULTS: Twenty-five patients with a mean of 38.6±10.6 months (24-62) of follow-up were included. The mean age at surgery was 12.2 (10-14), and the median Sanders stage was 3 (1-7). A mean of 7.7±1.1 (6-11) levels were tethered. The mean preoperative main thoracic curve magnitude of 46°±7.7° was corrected to 23.3°±5.9° postoperatively, which was subsequently modulated to 12° ±11.5° during the follow-up. At the time of the MRI (mean 29±9.5 (24-62) months), the median Sanders stages was 7 (5-8). A total of 217 levels of discs and bilateral facet joints were evaluated in the preoperative and follow-up MRI images. Analyses of disc and facet scores revealed no significant differences between patients. Deterioration of previously degenerated discs was noted in one patient (from grade 2 to 3), while previously healthy lower adjacent facet joints were degenerated (grade 2) in another patient. CONCLUSIONS: Intermediate discs and facet joints were preserved after growth modulation with VBT surgery at a mean of 29 months of follow-up. Studies in larger cohorts with longer follow-up are warranted to have more in-depth analyses of the effects of relative stabilization and altered biomechanical loads.
BACKGROUND CONTEXT: Vertebral body tethering (VBT), a flexible compression-based growth modulation technique, was claimed to prevent disc degeneration due to its less rigid nature compared to other growth-friendly techniques. Yet, the consequences of VBT surgery on discs and facet joints have not been precisely acknowledged. PURPOSE: The purpose of this study was to determine the changes in the intermediate and adjacent levels at least 2 years after surgery. STUDY DESIGN/ SETTING: Prospectively-followed consecutive patient cohort PATIENT SAMPLE: Adolescent idiopathic scoliosis patients who underwent thoracoscopic VBT between 2014 and 2017 were included. OUTCOME MEASURES: Degeneration of the intervertebral discs using the Pfirrmann classification; Degeneration of facet joints using a scale of 0 to 3. METHODS: Demographic, perioperative, clinical, radiographic data were collected. Skeletal maturity and height gain were assessed in every follow-up. Overcorrection, tether breakage, mechanical and pulmonary complications as well as readmission and reoperations were recorded. MRIs taken before surgery and at a minimum of 2 years follow-up were evaluated for degeneration at the intermediate and adjacent segment intervertebral discs and facet joints by a blinded senior radiologist and compared. RESULTS: Twenty-five patients with a mean of 38.6±10.6 months (24-62) of follow-up were included. The mean age at surgery was 12.2 (10-14), and the median Sanders stage was 3 (1-7). A mean of 7.7±1.1 (6-11) levels were tethered. The mean preoperative main thoracic curve magnitude of 46°±7.7° was corrected to 23.3°±5.9° postoperatively, which was subsequently modulated to 12° ±11.5° during the follow-up. At the time of the MRI (mean 29±9.5 (24-62) months), the median Sanders stages was 7 (5-8). A total of 217 levels of discs and bilateral facet joints were evaluated in the preoperative and follow-up MRI images. Analyses of disc and facet scores revealed no significant differences between patients. Deterioration of previously degenerated discs was noted in one patient (from grade 2 to 3), while previously healthy lower adjacent facet joints were degenerated (grade 2) in another patient. CONCLUSIONS: Intermediate discs and facet joints were preserved after growth modulation with VBT surgery at a mean of 29 months of follow-up. Studies in larger cohorts with longer follow-up are warranted to have more in-depth analyses of the effects of relative stabilization and altered biomechanical loads.
Authors: Sara Costanzo; Andrea Pansini; Luca Colombo; Valentina Caretti; Petar Popovic; Giulia Lanfranchi; Anna Camporesi; Gloria Pelizzo Journal: Children (Basel) Date: 2022-01-05