Use of a novel corrective device for correction of deformities in adolescent idiopathic scoliosis

Systematic review and meta-analysis for the impact of rod materials and sizes in the surgical treatment of adolescent idiopathic scoliosis

PURPOSE

To assess surgical and safety outcomes associated with different rod materials and diameters in adolescent idiopathic scoliosis (AIS) surgery.

METHODS

A systematic literature review and meta-analysis evaluated the surgical management of AIS patients using pedicle screw fixation systems (i.e., posterior rods and pedicle screws) with rods of different materials and sizes. Postoperative surgical outcomes (e.g., kyphosis and coronal correction) and complications (i.e., hyper/hypo-lumbar lordosis, proximal junctional kyphosis, revisions, reoperations, and infections) were assessed. Random-effects models (REMs) pooled data for outcomes reported in ≥ 2 studies.

RESULTS

Among 75 studies evaluating AIS surgery using pedicle screw fixation systems, 46 described rod materials and/or diameters. Two studies directly comparing titanium (Ti) and cobalt-chromium (CoCr) rods found that CoCr rods provided significantly better postoperative kyphosis angle correction vs. Ti rods during a shorter follow-up (0-3 months, MD = - 2.98°, 95% CI - 5.79 to - 0.17°, p = 0.04), and longer follow-up (≥ 24 months, MD = - 3.99°, 95% CI - 6.98 to - 1.00, p = 0.009). Surgical infection varied from 2% (95% CI 1.0-3.0%) for 5.5 mm rods to 4% (95% CI 2.0-7.0%) for 6 mm rods. Reoperation rates were lower with 5.5 mm rods 1% (95% CI 0.0-3.0%) vs. 6 mm rods [6% (95% CI 2.0-9.0%); p = 0.04]. Differences in coronal angle, lumbar lordosis, proximal junctional kyphosis, revisions, and infections did not differ significantly (p > 0.05) among rods of different materials or diameters.

CONCLUSION

For AIS, CoCr rods provided better correction of thoracic kyphosis compared to Ti rods. Patients with 5.5 mm rods had fewer reoperations vs. 6.0 and 6.35 mm diameter rods.

LEVEL OF EVIDENCE

III.

Risk Factors of Total Blood Loss and Hidden Blood Loss in Patients with Adolescent Idiopathic Scoliosis: A Retrospective Study

Objectives

To investigate the risk factors of total blood loss (TBL) and hidden blood loss (HBL) in adolescent idiopathic scoliosis (AIS) patients undergoing posterior orthopedic surgery.

Methods

The AIS patients who visited department of spine surgery between January 2015 and December 2020 were retrospectively reviewed. Those with a history of posterior orthopedic surgery for AIS were identified, and their clinical data were collected. Gross formula was used to calculate the TBL and HBL. SPSS 20.0 was used for statistical analysis. The potential risk factors of TBL and HBL were assessed by independent t-test or univariate analysis. The risk factors of TBL and HBL were determined by multiple linear regression.

Results

A total of 114 patients were included in this study. Operative time (P < 0.001), postoperative platelets (PLT) (P = 0.001), the number of surgical fixation segments (P < 0.001), implanted screws (P < 0.001), hospital stay (P = 0.006), type of scoliosis (P < 0.001), and correction angle of scoliosis (P = 0.063) were the potential risk factors of TBL. Operative time (P < 0.000), postoperative PLT (P = 0.095), the number of surgical fixation segments (P < 0.001), implanted screws (P < 0.001), type of scoliosis (P < 0.001), correction angle of scoliosis (P = 0.073), and total blood volume (P = 0.098) were the potential risk factors of HBL. Multiple linear regression analysis showed that operative time (P = 0.003) and the number of surgical fixation segments (P = 0.014) were risk factors of TBL, while the number of surgical fixation segments (P = 0.004) was a risk factor of HBL.

Conclusions

In AIS patients undergoing posterior internal fixation surgery, the operative time and the number of surgical fixation segments are risk factors of TBL, and the number of surgical fixation segments is a risk factor of HBL. Surgeons need to consider these factors when making surgical strategies for AIS patients.

Rod Link Reducer system in adolescent idiopathic scoliosis: a retrospective observational trial

PURPOSE

The Rod Link Reducer (RLR) (Globus Medical, PA, USA) allows direct three-dimensional correction of the spine deformity follows the direct vertebral rotation (DVR) theories. The purpose of this retrospective study is to compare RLR with traditional correction technique (TCT) in two cohorts of patients with adolescent idiopathic scoliosis (AIS).

METHODS

Fifty-four patients (M:F = 1:8) between 2018 and 2020 were included. The first group (n = 22) was treated by RLR while the second one (n = 32) by TCT. All spines were classified as per the Lenke system. Length of hospitalization, days in intensive care unit (ICU), operative time, and blood loss were recorded. SRS-30 and SF-36 questionnaires were administered pre-operative and post-operative. We collected radiological data: pre-operative and post-operative Cobb angles, coronal and sagittal balance, trunk and thoracic height.

RESULTS

RLR and TCT groups are homogeneous in age (p = 0.317), sex ratio (p = 0.347), and Risser stage (p = 0.222). Between both groups there was no significant statistical difference in haemoglobin value, hospitalization length, days in ICU, operative times, SF-36, SRS-30, NRS, and perceived satisfaction. RLR group shows a better improvement of correction of main thoracic (MT) curve (RLR 54.2% ± 15.9%/TCT 38.1% ± 20.4%, p = 0.031). Nevertheless, RLR group shows a worse thoracic kyphosis correction (RLR 16.82° ± 9.13°/27.12° ± 12.13°, p = 0.015).

CONCLUSION

RLR system allows a more effective MT curve correction than TCT systems, but it seems to give a hypokyphosis effect.

Relationship Between Electromyographic Frequency of the Erector Spinae and Location, Direction, and Number of Spinal Curvatures in Children with Scoliotic Changes

INTRODUCTION

The aim of the study was to assess the relationship between erector spinae electromyographic frequency (SEMG) and the location, direction and number of spinal curvatures in children with scoliotic changes.

METHODS

Analysis comprised 103 (42,21%) children with scoliosis and 141 (57.79%) with scoliotic posture. Body posture and the spine were examined using the Diers formetric III 4D optoelectronic method. Electromyographic analysis was performed using a 14-channel Noraxon TeleMyo DTS apparatus.

RESULTS

In girls, the highest mean SEMG frequency of the erector spinae, calculated from 16 measurements, occurred in the case of scoliotic posture (Mean = 73.69 Hz), while in boys, the greatest values were noted for scoliosis (Mean = 79.75 Hz). There was a significant correlation between erector spinae SEMG frequency and curvature location, both in the scoliosis group (p = 0.003) and in the group with scoliotic posture (p = 0.04). There was also a significant correlation between SEMG frequency of the erector spinae and direction of the curvature, both in the scoliosis (p = 0.01) and scoliotic posture groups (p = 0.04), as well as between the erector spinae SEMG frequency and the number of spinal curvatures (scoliosis group: p = 0.03; scoliotic posture group: p = 0.03).

CONCLUSION

The study is of applicative value and fills the gap in research on erector spinae SEMG frequency of in low-grade scoliosis among small children. Our research can also be used in research on the etiology and progression scoliosis. Visible disturbances in the erector spinae SEMG frequency (activity and tension) contribute to the development of curvature and testify to the fact that these changes are the primary cause of idiopathic scoliosis. Scoliosis is merely a symptom, an external expression of CNS dysfunction that is not fully recognised. It is also visible on the SEMG record of postural muscles. Our objective is to contribute to creating a future model record for SEMG of the postural muscles, characteristic for children with scoliosis. Then, based on electromyographic examination, it will be possible to identify initial symptoms of scoliosis and start preventive rehabilitation before irreversible bone changes occur.