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Purpose Vertebral body tethering (VBT) is an alternative to fusion for selected scoliosis patients. As VBT does not limit spine mobility, it has been propagated that this technique allows a quicker return to physical activity than fusion. However, no data are available to support this statement. Aim of this study was to quantify how much time patients required to resume preoperative activity level and to seek possible associations between return to physical activity and demographic, radiographic and surgical data. Methods One year postoperatively, the validated sport activity questionnaire (SAQ) was administered to all skeletally immature patients who underwent VBT at our institution. SAQ data were analyzed and a multivariate analysis was conducted to investigate associations between SAQ and demographic, radiographic and surgical data. Results Thirty-one patients aged 14.5 years completed the SAQ. Within 3 months from VBT, 97% returned to school, 61% resumed physical education, 97% carried a backpack, 68% run, and 82% rode a bike; 70% bent within a month from VBT. Ninety-four percent of patients returned to their preoperative athletic level. Within 3 months, 63% of responders resumed noncontact, 61% contact and 53% collision sports. No relevant associations were observed between the SAQ and demographic, radiographic and surgical data. In particular, number of instrumented vertebrae, level of the lowest instrumented vertebra and postoperative Cobb angle did not influence patients’ return to preoperative activities. Conclusion VBT allows patients to quickly return to their preoperative activity level, irrespectively of the postoperative Cobb angle or type of instrumentation.

Vertebral body tethering (VBT), otherwise known as fusion-less anterior scoliosis correction (ASC), is a new and increasingly interesting therapeutic option for selected scoliosis patients. The available data on this surgical technique are still limited and guidelines on patient selection or surgical timing are not available. The aim of this study was to conduct a systematic review of the available literature on VBT. The analysis was performed in accordance with the PRISMA Statement. Nine studies with data from 175 patients were available. On average, 7.3 vertebrae were instrumented. Surgical time was 230 min and the estimated blood loss 153 ml. The mean correction on the coronal plane was 52%, and there was no significant change in sagittal parameters. The revision rate was 18.9%. The methodological quality assessment with the Coleman score gave unsatisfactory results, so that available data are not sufficient to propose general indications or guidelines to perform VBT.

Purpose There is a paucity of studies on new vertebral body tethering (VBT) surgical constructs especially regarding their potentially motion-preserving ability. This study analyses their effects on the ROM of the spine. Methods Human spines (T10-L3) were tested under pure moment in four different conditions: (1) native, (2) instrumented with one tether continuously connected in all vertebrae from T10 to L3, (3) additional instrumented with a second tether continuously connected in all vertebrae from T11 to L3, and (4) instrumented with one tether and one titanium rod (hybrid) attached to T12, L1 and L2. The instrumentation was inserted in the left lateral side. The intersegmental ROM was evaluated using a magnetic tracking system, and the medians were analysed. Please check and confirm the author names and initials are correct. Also, kindly confirm the details in the metadata are correct. The mentioned information is correct Results Compared to the native spine, the instrumented spine presented a reduction of less than 13% in global ROM considering flexion–extension and axial rotation. For left lateral bending, the median global ROM of the native spine (100%) significantly reduced to 74.6%, 66.4%, and 68.1% after testing one tether, two tethers and the hybrid construction, respectively. In these cases, the L1-L2 ROM was reduced to 68.3%, 58.5%, and 38.3%, respectively. In right lateral bending, the normalized global ROM of the spine with one tether, two tethers and the hybrid construction was 58.9%, 54.0%, and 56.6%, respectively. Considering the same order, the normalized L1-L2 ROM was 64.3%, 49.9%, and 35.3%, respectively. Conclusion The investigated VBT techniques preserved global ROM of the spine in flexion–extension and axial rotation while reduced the ROM in lateral bending.

Introduction Vertebral body tethering (VBT) presents new challenges in respect to radiation exposure, as screws cannot be placed free-hand and the lateral positioning of the patients increases scattered radiation. To reduce radiation exposure, we introduced the use of electronic conductivity device (ECD). These are drilling probes send an audio signal when cortical bone is breached. Thus, anterior, bicortical screws can be placed without multiple fluoroscopic controls. ECD has been used for all VBT procedures at our institution starting April 2020. The aim of this study was to test the safety of ECD and its efficacy in radiation reduction in comparison with the current standard, the fluoroscopic guidance. Materials and methods All patients who underwent VBT between August 2019 and December 2020 were retrospectively reviewed and divided into two groups according to whether ECD had been used or not. The radiation exposure per procedure and per screw was compared among the two groups, overall and separately for thoracic, lumbar and bilateral procedures. The rate of misplaced screws was calculated. Results Data from 62 patients and 825 screws were obtained (397 with ECD). No screw misplacement was observed. Radiation reduction with ECD reached up to 41%. A significant reduction was observed in the radiation per procedure in bilateral instrumentation (from 9.16 to 5.52 mGy*m2), and in the analysis per screw overall (from 9.16 to 5.52 mGy*m2) and for lumbar curves (from 0.54 to 0.32 mGy*m2). Conclusion ECD can safely and effectively reduce the radiation exposure for VBT procedures.