Risk factors for proximal junctional kyphosis after pediatric spinal deformity surgery with halo gravity traction

Radiological and Pulmonary Results of Surgical Treatment of Severe Idiopathic Scoliosis Using Preoperative Halo Gravity Traction Compared with Less Invasive Temporary Internal Distraction in Staged Surgery in Adolescents

Background: Severe and rigid scoliosis represents a type of spinal deformity characterized by a Cobb angle exceeding 90° and a flexibility of less than 30%. Halo spinal traction remains the established standard for managing severe scoliosis, although alternative approaches such as temporary internal distraction rods and staged surgical correction exist. The primary objective of this investigation was to compare two cohorts of patients treated using these distinct methods to ascertain any divergences in terms of surgical and radiological outcomes, pulmonary function (PF), and quality of life (QoL). Methods: This study encompassed a total of 62 pediatric patients meeting the specified criteria, which included severe idiopathic scoliosis (major Cobb curve >90) and flexibility <30%. Group 1 (G1) underwent surgical intervention involving preoperative Halo gravity traction (HGT) succeeded by posterior spinal fusion (PSF). On the other hand, Group 2 (G2) underwent a two-stage procedure starting with a less invasive temporary internal distraction technique (LITID) prior to PSF. The radiological outcomes, PF, and QoL were documented and assessed over a monitoring period ranging from 2 to 5 years. Results: The average preoperative major curves (MCs) measured 124° and 122° in G1 and G2, respectively (p < 0.426). Initial flexibility, as observed in preoperative bending films, ranged from 18% in G1 to 21% in G2 (p < 0.001). Following the ultimate surgical intervention, the MCs were corrected to 45° and 37.4° in G1 and G2, respectively (p < 0.001). The percentage correction of the MCs was higher in G2 (63% vs. 70% in G1 and G2, respectively), with significant between-group disparities (p < 0.001). The mean preoperative thoracic kyphoses (TKs) were 96.5° in G1 and 92° in G2 (p = 0.782), which were rectified to 45.8° in G1 and 36.2° in G2 (p < 0.001), equating to correction rates of 55% and 60% in the respective groups. Initially, G2 exhibited lower values for the percentage of predicted lung volume (FVC) and predicted FEV1 compared with G1 (49% and 58% vs. 54.5% and 60.8%; N.S.). Nonetheless, both groups demonstrated enhancements in their FVC and FEV1 values over the follow-up period. Conclusions: The surgical management of severe and untreated spinal curvatures in the pediatric and adolescent population can be considered safe, with a tolerable incidence of minor complications. LITID emerges as a method offering improved QoL and pulmonary function, achieving notably substantial average corrections in deformity by 70% in the coronal plane and 60% in the sagittal plane, alongside a mean increase in trunk height of 10.8 cm. Furthermore, a typical reduction of 76% in rib humps and enhancements in respiratory function, as indicated by improvements in 1 s predicted forced expiratory volume (by 25-56%) and forced vital capacity (by 35-65%), were achieved, leading to a clinically and statistically significant enhancement in QoL when evaluated using SRS-22r, without resorting to more radical, high-risk procedures.

Incidence and risk factors of proximal junctional kyphosis in adolescent idiopathic scoliosis after correction surgery: a meta-analysis and systematic review

AIM

To analyze the risk factors of proximal junctional kyphosis (PJK) after correction surgery in patients with adolescent idiopathic scoliosis (AIS).

METHODS

PubMed, Medline, Embase, Cochrane Library, Web of Science, CNKI, and EMCC databases were searched for retrospective studies utilizing all AIS patients with PJK after corrective surgery to collect preoperative, postoperative, and follow-up imaging parameters, including thoracic kyphosis (TK), lumbar lordosis (LL), proximal junctional angle (PJA), the sagittal vertical axis (SVA), pelvic incidence (PI), pelvic tilt (PT), pelvic incidence-lumbar lordosis (PI-LL), sacral slope (SS), rod contour angle (RCA) and upper instrumented vertebra (UIV).

RESULTS

Nineteen retrospective studies were included in this meta-analysis, including 550 patients in the intervention group and 3456 patients in the control group. Overall, sex (OR 1.40, 95% CI (1.08, 1.83), P = 0.01), larger preoperative TK (WMD 6.82, 95% CI (5.48, 8.16), P < 0.00001), larger follow-up TK (WMD 8.96, 95% CI (5.62, 12.30), P < 0.00001), larger postoperative LL (WMD 2.31, 95% CI (0.91, 3.71), P = 0.001), larger follow-up LL (WMD 2.51, 95% CI (1.19, 3.84), P = 0.0002), great change in LL (WMD - 2.72, 95% CI (- 4.69, - 0.76), P = 0.006), larger postoperative PJA (WMD 4.94, 95% CI (3.62, 6.26), P < 0.00001), larger follow-up PJA (WMD 13.39, 95% CI (11.09, 15.69), P < 0.00001), larger postoperative PI-LL (WMD - 9.57, 95% CI (- 17.42, - 1.71), P = 0.02), larger follow-up PI-LL (WMD - 12.62, 95% CI (- 17.62, - 7.62), P < 0.00001), larger preoperative SVA (WMD 0.73, 95% CI (0.26, 1.19), P = 0.002), larger preoperative SS (WMD - 3.43, 95% CI (- 4.71, - 2.14), P < 0.00001), RCA (WMD 1.66, 95% CI (0.48, 2.84), P = 0.006) were identified as risk factors for PJK in patients with AIS. For patients with Lenke 5 AIS, larger preoperative TK (WMD 7.85, 95% CI (5.69, 10.00), P < 0.00001), larger postoperative TK (WMD 9.66, 95% CI (1.06, 18.26), P = 0.03, larger follow-up TK (WMD 11.92, 95% CI (6.99, 16.86), P < 0.00001, larger preoperative PJA (WMD 0.72, 95% CI (0.03, 1.41), P = 0.04, larger postoperative PJA (WMD 5.54, 95% CI (3.57, 7.52), P < 0.00001), larger follow-up PJA (WMD 12.42, 95% CI 9.24, 15.60), P < 0.00001, larger follow-up SVA (WMD 0.07, 95% CI (- 0.46, 0.60), P = 0.04), larger preoperative PT (WMD - 3.04, 95% CI (- 5.27, - 0.81), P = 0.008, larger follow-up PT (WMD - 3.69, 95% CI (- 6.66, - 0.72), P = 0.02) were identified as risk factors for PJK.

CONCLUSION

Following corrective surgery, 19% of AIS patients experienced PJK, with Lenke 5 contributing to 25%. Prior and post-op measurements play significant roles in predicting PJK occurrence; thus, meticulous, personalized preoperative planning is crucial. This includes considering individualized treatments based on the Lenke classification as our future evaluation standard.

No Benefits in Using Magnetically Controlled Growing Rod as Temporary Internal Distraction Device in Staged Surgical Procedure for Management of Severe and Neglected Scoliosis in Adolescents

BACKGROUND

Severe spinal curvatures (SSCs) in children and adolescents have long been treated with preoperative Halo traction, in its various variations. There are also several radical techniques available for the management of neglected SSCs, such as osteotomies; however, these can be risky. Comparing the treatment outcomes when using preoperative Halo Gravity Traction (HGT) against the use of a Magnetically Controlled Growing Rod (MCGR) as a temporary internal distraction (TID) device, we evaluated the differences in surgical and radiological outcomes.

METHODS

We conducted a retrospective study of 30 patients with SSCs, treated with HGT followed by posterior spinal fusion (PSF; Group 1, n = 18) or treated using a temporary MCGR as a TID followed by PSF (Group 2, n = 12). All patients underwent surgical treatment between 2016 and 2022. The inclusion criteria were SSC > 90°, flexibility < 30%, and the use of preoperative HGT followed by PSF or the two-stage surgical procedure with initial TID rod placement (Stage 1) followed by PSF (Stage 2). The evaluated parameters were as follows: rib hump, trunk height, and radiographic outcomes. All parameters were collected preoperatively, after the initial surgery, after final correction and fusion, and during the final follow-up.

RESULTS

In Group 1, we evaluated 18 patients with a mean age of 15.5 years; in Group 2, we evaluated 12 patients with a mean age of 14.2 years. The interval between the staged procedures averaged 32.7 days. The mean preoperative main curves (MC) were 118° and 112° in Group 1 and Group 2, respectively. After definitive surgery, the MC was corrected to 42° and 44° in G1 and G2, respectively. The mean percentage correction of the MC was similar in both groups (65% vs. 61% in G1 and G2, respectively). The mean preoperative thoracic kyphosis was 92.5° in G1 and 98° in G2, corrected to 43.8° in G1 and 38.8° in G2. Trunk height increased by 9 cm on average.

CONCLUSIONS

There are no benefits in using a MCGR as a temporary internal distraction device in the management of neglected scoliosis in adolescents. Surgical treatment of severe scoliosis may be safe, with a reduced risk of potential complications, when using preoperative HGT. A specific intraoperative complication when using a MCGR as a temporary internal distraction device was a 50% risk of transient neuromonitoring changes, due to significant force applied to the spine and radical distraction of the spine. We achieved similar clinical, radiographic, and pulmonary function outcomes for both techniques. The use of HGT causes less blood loss with a shorter overall time under anesthesia. Partial correction significantly aids the subsequent operation by facilitating a gradual reduction in the curvature, thereby reducing the difficulty of surgical treatment and the risk of neurological deficits.