Anterior vertebral body tethering (AVBT) was introduced as a fusionless alternative to treating adolescent idiopathic scoliosis (AIS) while preserving range of motion (ROM). This is the first systematic review to compare the ROM outcomes between AVBT and PSF in treating AIS.
We conducted a comprehensive search on PubMed, EMBASE, MEDLINE, and Cochrane Library. Inclusion criteria were patients with AIS treated with AVBT or PSF or both, and clearly defined ROM outcomes; exclusion criteria were scoliosis other than AIS, biomechanical or cadaveric studies, non-English publications, case reports, conference summaries, unpublished literature, commentaries, and reviews. Primary outcome was ROM. Secondary outcomes included Cobb angle correction, quality of life (QOL), complications, and muscle strength and endurance.
Twelve studies were included in this review. We found moderate evidence to support that AVBT results in superior ROM outcomes than PSF while achieving comparable Cobb angle correction with low evidence. The comparison of QOL outcomes between AVBT and PSF remained inconclusive. In addition to the complications noted conventionally in PSF, AVBT could result in over-correction and distal adding-on. We also found very low evidence to support that AIS patients treated with AVBT have superior muscle strength and endurance when compared to those treated with PSF.
AVBT provides better preservation of ROM and muscle strength postoperatively when compared with PSF, while achieving comparable curve correction. Future studies should explore the spinal growth trajectory to determine the window of opportunity for AVBT in AIS.

Restoration of three-dimensional (3D) alignment is critical in correcting patients with adolescent idiopathic scoliosis using posterior spinal fusion (PSF). However, current studies mostly rely on 2D radiographs, resulting in inaccurate assessment of surgical correction and underlying predictive factors. While 3D reconstruction of biplanar radiographs is a reliable and accurate tool for quantifying spinal deformity, no study has reviewed the current literature on its use in evaluating surgical prognosis.
To summarize the current evidence on patient and surgical factors affecting sagittal alignment and curve correction after PSF based on 3D parameters derived from reconstruction of biplanar radiographs.
A comprehensive search was conducted by three independent investigators on Medline, PubMed, Web of Science, and Cochrane Library to obtain all published information on predictors of postoperative alignment and correction after PSF. Search items included \"adolescent idiopathic scoliosis,\" \"stereoradiography,\" \"three-dimensional,\" \"surgical,\" and \"correction.\" The inclusion and exclusion criteria were carefully defined to include clinical studies. Risk of bias was assessed with the Quality in Prognostic Studies tool, and level of evidence for each predictor was rated with the Grading of Recommendations, Assessment, Development, and Evaluations approach. 989 publications were identified, with 444 unique articles subjected to full-text screening. Ultimately, 41 articles were included.
Strong predictors of better curve correction included preoperative normokyphosis (TK > 15°), a corresponding rod contour, intraoperative vertebral rotation and translation, and upper and lower instrumented vertebrae selected based on sagittal and axial inflection points. For example, for Lenke 1 patients with junctional vertebrae above L1, fusion to NV-1 (1 level above the neutral vertebra) achieved optimal curve correction while preserving motion segments. Pre-op coronal Cobb angle and axial rotation, distal junctional kyphosis, pelvic incidence, sacral slope, and type of instrument were identified as predictors with moderate evidence. For Lenke 1C patients, > 50% LIV rotation was found to increase spontaneous lumbar curve correction. Pre-op thoracolumbar apical translation and lumbar lordosis, Ponte osteotomies, and rod material were found to be predictors with low evidence.
Rod contouring and UIV/LIV selection should be based on preoperative 3D TK in order to achieve normal postoperative alignment. Specifically, Lenke 1 patients with high-lying rotations should be fused distally at NV-1, while hypokyphotic patients with large lumbar curves and truncal shift should be fused at NV to improve lumbar alignment. Lenke 1C curves should be corrected using > 50% LIV rotation counterclockwise to the lumbar rotation. Further investigation should compare surgical correction between pedicle-screw and hybrid constructs using matched cohorts. DJK and overbending rods are potential predictors of postoperative alignment.

The aim of this meta-analysis was to analyze the results of one-stage all-posterior spinal fusion for severe adolescent idiopathic scoliosis (AIS). A systematic search of articles about one-stage posterior spinal fusion for severe AIS was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Data about population, pre-and postoperative radiographical data, surgical procedure details, and complications were extracted. Meta-analyses were performed when possible. Fourteen studies (640 patients) were included. The mean Cobb angle of the major curve varied from 80.0 ± 7.3 to 110.8 ± 12.1. The meta analysis showed a comprehensive coronal correction rate of the major curve of 58.6%, a comprehensive operative time of 274.5 min, and a comprehensive estimated intraoperative blood loss of 866.5 mL (95% confidence interval: 659.3-1073.6, I 2 ≈ 0%). A total of 48 complications (5.4%) were reported. Overall, the meta-analysis showed a major complication rate of 4%. In seven cases, revision surgery was needed. Posterior-only approach is effective enough to correct severe curves and can spare the patient possible adverse events due to anterior approach. However, when choosing this approach for severe AIS, screw density needs to be high and posterior column osteotomies may need to be planned to mobilize the spine and maximize correction.

Gabapentin has been adopted in Enhanced Recovery After Surgery protocols as a means to reduce opioid consumption while maintaining adequate post-operative analgesia. The purpose of our study was to review and compare changes in length of stay, opioid use, and patient reported pain scores after the addition of gabapentin into five, distinct pain protocols for posterior spinal fusion in adolescent idiopathic scoliosis.
A retrospective review was completed using a database of electronic medical data from a single pediatric orthopedic healthcare system that was queried for patients with adolescent idiopathic scoliosis who underwent first-time posterior spinal fusion. Perioperative data including demographics, hospital length of stay, surgical details, opioid use, patient reported pain scores, and non-opioid analgesic use were collected.
From December 2012 to February 2019, 682 hospitalizations for posterior spinal fusion in adolescent idiopathic scoliosis were identified with complete inpatient data; 49% were administered gabapentin. For the gabapentin cohort, the system saw no statistically significant effect on length of stay or pain averaged over POD#0-3. Opioid use was statistically lower averaged over POD#0-3. Individual sites saw variation on length of stay and opioid use compared to the system.
In conclusion, system-wide data showed gabapentin containing protocols reduced opioid use while maintaining clinically equivalent analgesia. However, variations of individual site results make it difficult to conclude the degree to which gabapentin were responsible for this effect.

METHODS: A systematic review and meta-analysis.
OBJECTIVE: The purpose of this systematic review and meta-analysis was to compare the efficacy of lateral lumbar interbody fusion (LLIF) combined with posterior spinal fusion (PSF) with that of conventional PSF in the treatment of adult spinal deformity (ASD).
METHODS: A comprehensive literature search was performed for relevant studies in PubMed, EMBASE, Web of Science, and the Cochrane Library. Spinopelvic parameters, surgical data, complications, and clinical outcomes at the last follow-up were compared between patients with ASD who underwent LLIF combined with PSF (LLIF+PSF group) and those who underwent conventional PSF (only-PSF group).
RESULTS: Ten studies, comprising 621 patients with ASD (313 in the LLIF+PSF group and 308 in the only-PSF group), were included. The level of evidence was III for 7 studies and IV for 3 studies. There was no significant difference in the improvement in the visual analog scale score, systemic complication rate, and revision rate between groups. In the LLIF+PSF group, we noted a superior restoration of lumbar lordosis (weighted mean difference [WMD], 9.77; 95% confidence interval [CI] 7.10 to 12.44, P < .001), pelvic tilt (WMD, -2.50; 95% CI -4.25 to -.75, P = .005), sagittal vertical axis (WMD, -21.92; 95% CI -30.73 to -13.11, P < .001), and C7 plumb line-center sacral vertical line (WMD, -4.03; 95% CI -7.52 to -.54, P = .024); a lower estimated blood loss (WMD, -719.99; 95% CI -1105.02 to -334.96, P < .001) while a prolonged operating time (WMD, 104.89; 95% CI 49.36 to 160.43, P < .001); lower incidence of pseudarthrosis (risk ratio [RR], .26; 95% CI .08 to .79, P = .017) while higher incidence of neurologic deficits (RR, 2.04; 95% CI 1.27 to 3.25, P = .003); and a better improvement in Oswestry Disability Index score (WMD, -7.04; 95% CI -10.155 to -3.93, P < .001) and Scoliosis Research Society-22 total score (WMD, .27; 95% CI .11 to .42, P = .001). The level of evidence in this systematic review and meta-analysis was II.
CONCLUSIONS: Compared with conventional PSF, LLIF combined with PSF was associated with superior restoration of sagittal and coronal alignment, lower incidence of pseudarthrosis, better improvement in quality of life, and less surgical invasiveness in the treatment of ASD, albeit at the cost of prolonged surgical times and substantially high incidence of lower extremity symptoms. Surgeons should weigh the advantages and disadvantages of this procedure, and inform patients about its side effects.

Minimally invasive surgery (MIS) techniques for posterior spine pedicle-screw fusion (PSF) may reduce the AIS surgery invasiveness, although they require a certain degree of patient selection based on the severity of the curve. The aim of this article is to systematically review the Literature to determine efficacy and safety of MIS-PSF in AIS correction, and to compare its outcomes with open-PSF. A systematic search of electronic databases from eligible articles was conducted. Only studies adopting MIS-PSF for AIS were included. Clinical and radiographic outcomes were extracted and summarized. Meta-analyses were performed. P-value < 0.05 was considered significant. Thirteen studies for a total of 635 patients ungergoing MIS-PSF were included in this review. Pre-operative Cobb\'s angle ranged from 48.3°±4.2° to 59.8°±6.6°, coronal correction from 58.1% to 79.1%, average operative time ranged from 252 to 526.8 min, average estimated blood loss from 138.8 ± 50 to 1250 mL. Sixty-seven complications were recorded (9.9%), with 19 revisions (3.8%), resulting similar to those described in Literature using open-PSF. At meta-analysis, MIS-PSF (321 patients) compared to open-PSF (429 patients) showed lower coronal correction (although no statistically significant difference was found), estimated blood loss and length of hospital stay, but higher operative time. No differences in SRS-22, complications and revision rate were found. In conclusion, open-PSF shows a trend towards higher correction in the coronal plane and requires a shorter operative time when compared to MIS-PSF. It remains the gold standard for AIS correction, although MIS-PSF seems to be a viable and promising technique for selected patients. - KEYWORDS: minimally invasive surgery, minimally invasive techniques, adolescent idiopathic scoliosis, posterior spinal fusion, pedicle-screws-only instrumentation.

UNASSIGNED: A variety of different lumbar spinal fusion techniques have been developed. In this study, we review published medical literature highlighting the differences between lumbar interbody fusion techniques with regard to their surgical technique, clinical outcomes, and complications.
UNASSIGNED: PubMed, ScienceDirect, and Google Scholar searches were performed for studies published between January 1990 to April 2018 reporting spinal fusion surgery clinical outcomes of at least one fusion technique. Clinical outcomes were extracted and pooled by surgical technique. Chi-squared analyses and Fisher Exact Tests were used to determine differences in rates between groups.
UNASSIGNED: PLIF had the highest rate of successful fusion (97% [155/159]) and the lowest rate of complications (4% [6/131]). A chi square analysis revealed a significant difference in fusion success in PLIF compared to PLF (84% [278/330], p < .001). PLIF also had significantly fewer complications compared to PSF (14.7% [251/1709], p = .001), PLF (13.4% [47/351], p = .008), ALIF (14.2% [22/155], p = .008), and LIC (13.9% [47/339], p = .005). Additionally, there were significant differences in the rate of successful fusion when comparing lateral interbody cage (LIC) techniques (p = .041), which include OLIF (100% [63/63]), DLIF (92% [24/26]), and XLIF (87% [67/77]). LIC techniques overall had higher fusion success rates (93.0% [154/166] compared to PLF (p = .01), but a higher rate of complications (14% [47/339]) compared to PLIF (p = .005) and TLIF (6% [17/259], p = .005).
UNASSIGNED: Overall, PLF and XLIF have the lowest fusion success rates, and OLIF demonstrated a trend of higher fusion rates among LIC. Techniques that utilized interbody fusion tended to increase the rate of fusion. While interbody fusion techniques offer higher rates of fusion, complication rates also tend to rise with the increase in complexity of the surgical technique, as with OLIF which notably has the highest fusion rate and complication rate.

Pedicle screws are the gold standard in spine surgery, allowing a solid tricolumnar fixation which is unmatched by hooks and wires. The freehand technique is the most widely adopted for pedicle screws placing. While freehand technique has been classically performed with manual tools, there has been a recent trend toward the use of power tools. The aim of this review is to summarize and expose potential risks and advantages of power pedicle screws placing. The literature showed that the use of power tools offers an acceptable safety profile, comparable to manual technique. With an adequate training, the power technique may speed up the screw placing, reduce the fluoroscopy time and the physical stress to the spine surgeon. Regarding differences in pull-out strength between power and manual techniques, the literature is still uncertain and inconsistent, both in clinical and preclinical studies. The choice between the use of power and manual freehand pedicle screws placing is still based on the surgeon\'s own preference.

BACKGROUND: There has been a growing interest in using all pedicle screw construct in posterior spinal fusion (PSF) for adolescent idiopathic scoliosis (AIS) surgery in recent years. However, studies focusing on perioperative outcome and complications utilizing only pedicle screw system in AIS population are lacking. This study aims to evaluate perioperative outcomes and to determine the prevalence of major and minor complications following single-staged PSF for AIS.
METHODS: In this retrospective study of prospectively collected data, 1057 AIS patients operated between 2012 and 2019 were included. Main outcome measures were operative time, intraoperative blood loss, allogeneic blood transfusion rate, length of hospital stay after surgery, complication rate, and mean drop of haemoglobin (Hb) level. We documented the number of fusion levels, screw density, and postoperative radiographic parameters.
RESULTS: There were 917 females and 140 males. Majority were Lenke 1 curve type (46.9%). Mean age was 15.6 ± 3.7 years, with mean BMI of 18.6 ± 3.2 kg/m2. Mean operative time was 146.8 ± 49.4 min. Average intraoperative blood loss was 952.9 ± 530.4 ml with allogeneic blood transfusion rate of 5%. Mean screw density was 1.27 ± 0.21 screws per fusion level. Average hospital stay after surgery was 3.5 ± 0.9 days. Twenty-four complications were documented: twelve superficial infections (1.14%), five transient neurological deficits (0.47%), two deep infections (0.19%), two superior mesenteric artery syndrome, and one case each (0.09%) for massive intraoperative blood loss, intraoperative seizure, and lung atelectasis.
CONCLUSIONS: AIS patients treated with single-staged PSF using pedicle screw construct had a 0.95% rate of major complications and 1.32% rate of minor complications. Rate of neurologic complication was 0.47% while non-neurologic postoperative complications was 1.80% with infection being the leading complication at 1.32%.

A systematic review reporting on the efficacy of an ERAS protocol in patients undergoing spinal fusion for AIS.
To systematically evaluate the relevant literature pertaining to the efficacy of ERAS protocols with respect to the length of stay, complication, and readmission rates in patients undergoing posterior spinal corrective surgery for AIS. ERAS is a multidisciplinary approach aimed at improving outcomes of surgery by a specific evidence-based protocol. The rationale of this rapid recovery regimen is to maintain homeostasis so as to reduce the postoperative stress response and pain. No thorough review of available information for its use in AIS has been published.
A systematic review of the English language literature was undertaken using search criteria (postoperative recovery AND adolescent idiopathic scoliosis) using the PRISMA guidelines (Jan 1999-May 2020). Isolated case reports and case series with < 5 patients were excluded. Length of stay (LOS), complication and readmission rates were used as outcome measures. Statistical analysis was done using the random effects model.
Of a total of 24 articles, 10 studies met the inclusion criteria (9 were Level III and 1 of level IV evidence) and were analyzed. Overall, 1040 patients underwent an ERAS-type protocol following posterior correction of scoliosis and were compared to 959 patients following traditional protocols. There was a significant reduction in the length of stay in patients undergoing ERAS when compared to traditional protocols (p < 0.00001). There was no significant difference in the complication (p = 0.19) or readmission rates (p = 0.30). Each protocol employed a multidisciplinary approach focusing on optimal pain management, nursing care, and physiotherapy.
This systematic review demonstrates advantages with ERAS protocols by significantly reducing the length of stay without increasing the complications or readmission rates as compared to conventional protocols. However, current literature on ERAS in AIS is restricted largely to retrospective studies with non-randomized data, and initial cohort studies lacking formal control groups.
3.