3D-printed guides versus computer navigation for pedicle screw placement in the surgical treatment of congenital scoliosis deformities.

BACKGROUND: To compare the safety and clinical outcomes of 3D-printed guides versus computer navigation for pedicle screw placement in the correction of congenital scoliosis deformities. METHODS: The study was a single-centre retrospective controlled study and was approved by the hospital ethics committee for the analysis all patients under the age of 18 years with at least 2 years of follow-up. Sixty-three patients who underwent surgical correction for congenital scoliosis deformities in our hospital from January 2015 to December 2020 were divided into two groups based on the decision following preoperative doctor‒patient communication. Among them, 43 patients had pedicle screws placed with 3D-printed guider plates, while the remaining 20 patients had screws inserted with the assistance of computer navigation. The perioperative period, follow-up results and imaging data were compared between the groups. RESULTS: The operation was completed successfully for patients in both groups. The 3D-printed guide-assisted screw placement technique proved to be significantly superior to the computer navigation technique in terms of operation time, screw placement time, and intraoperative blood loss (p < .05), although the former had more frequent intraoperative fluoroscopies than the latter (p < .05). The mean follow-up time was 41.4 months, and the SRS-22 scores significantly improved in both groups over time postoperatively (p < .05). The 3D-printing group had better SRS-22 scores than the navigation group 6 months after surgery and at the last follow-up (p < .05). Compared with preoperative values, the coronal Cobb angle, local kyphotic Cobb angle, C7-S1 coronal deviation (C7PL-CSVL), and sagittal deviation (SVA) were significantly improved in both groups after surgery (p < .05). CONCLUSION: Both techniques achieve the purpose of precise screw placement and proper correction of the deformities. In contrast, the 3D-printed guide-assisted screw placement technique showed advantages in terms of operation time, screw placement time, intraoperative blood loss and patient satisfaction with outcomes.

Risk factors for misdiagnosis in children with developmental dysplasia of the hip: a retrospective single centre study.

OBJECTIVE: To investigate risk factors of misdiagnosis at the first visit of children with developmental dysplasia of the hip (DDH) who did not participate in hip ultrasound screening. METHODS: A retrospective review was conducted on children with DDH admitted to a tertiary hospital in northwestern China between January 2010 and June 2021. We divided the patients into the diagnosis and misdiagnosis groups according to whether they were diagnosed at the first visit. The basic information, treatment process and medical information of the children were investigated. We made a line chart of the annual misdiagnosis rate to observe the trend in the annual misdiagnosis rate. Univariate and multivariate logistic regression analyses were used to identify significant risk factors for missed diagnosis. RESULTS: A total of 351 patients met the inclusion criteria, including 256 (72.9%) patients in the diagnosis group and 95 (27.1%) patients in the misdiagnosis group. The line chart of the annual rate of misdiagnoses among children with DDH from 2010 to 2020 showed no significant change trend. Multiple logistic regression analysis showed that the paediatrics department (v the paediatric orthopaedics department: OR 0.21, p<0.001), the general orthopaedics department (v the paediatric orthopaedics department: OR 0.39, p=0.006) and the senior physician (v the junior physician: OR 2.47, p=0.006) on the misdiagnosis at the first visit of children were statistically significant. CONCLUSION: Children with DDH without hip ultrasound screening are prone to be misdiagnosed at their first visit. The annual misdiagnosis rate has not been significantly reduced in recent years. The department and title of the physician are independent risk factors for misdiagnosis.

Clinical efficacy of different open approaches in the surgical treatment of thoracolumbar tuberculosis: a single-center retrospective comparative study.

OBJECTIVE: To assess the clinical efficacy of three different surgical approaches in the treatment of thoracolumbar tuberculosis. METHODS: A total of 138 patients with thoracolumbar tuberculosis treated by open surgery were retrospectively analyzed. The surgical methods were divided into anterior, posterior and anterior-posterior combined. The hospital stays, amount of bleeding, operative time, preoperative, postoperative and last follow-up ESR, CRP, Frankel score, ODI, VAS, correction and loss rate of kyphosis, fusion rate and complications were recorded and analyzed. RESULTS: The average follow-up was 66 months. The average hospital stay, operative time and amount of bleeding of the anterior-posterior combined group were higher than other groups (P < 0.05). ESR and CRP of all patients were reduced postoperatively (P < 0.05). No significant difference among the three groups was found in the postoperative correction angle of kyphosis (P < 0.05), while the pre- and postoperative Cobb angle as well as correction rate had significant differences. The posterior approach could achieve better correction, and the loss of correction was more in the anterior group, 40.9 percent of patients performed correction loss. The Frankel score, VAS and ODI were significantly reduced among the three groups, and the incidence rate of complications of the anterior approach was lower than the other groups, with a significant difference (P < 0.05). CONCLUSION: The anterior approach has more advantages and fewer complications, which is supposed to give preference to and could not be replaced by the posterior and anterior-posterior combined approach.

Quantification of femoral position on radiographic acetabular coverage in children.

An accurate assessment of the radiographic acetabular coverage is essential for clinical diagnosis or surgical decision-making in hip disorders. This study aimed to evaluate the effect of femoral position on acetabular coverage and to predict the actual acetabular coverage from nonstandard radiographs. A total of 21 children (34 hips) with normative acetabular coverage were screened in this retrospective study. The Mimics-based local-rotation fluoroscopy simulation method was used to tilt, incline, and rotate the femur in 4° increments within the range of femoral motion. The acetabular coverage, namely acetabular-head index (AHI) and center-edge angle (CEA), increased with femoral abduction but decreased with other motions. Compared to the femoral neutral position, no significant differences were identified in AHI with the rotation (range: 0°-16°) and in CEA with the tilt (range: -20°-4°), inclination (range: 0°-4°), or rotation (range: -8°-40°). The linear regression analysis showed that the CEA increased by about 0.20° for each 1° increase in femoral inclination and decreased by about 0.01°, 0.07°, 0.06°, or 0.07° for each 1° increase in internal rotation, external rotation, flexion, or extension, respectively. And a more significant change in AHI was observed. All femoral malpositions, especially the inclination, affected radiographic acetabular coverage in children. Therefore, each pelvic radiograph should assess potential femoral malpositioning before diagnosing hip disorders. This study will assist surgeons in predicting the acetabular coverage on nonstandard radiographs.

Closing-opening wedge osteotomy for the treatment of congenital kyphosis in children.

BACKGROUND: To evaluate the safety and effectiveness of posterior closed-open wedge osteotomy for treatment of congenital kyphosis in children. METHODS: Imaging and clinical data from January 2010 to December 2019 of posterior closed-open wedge osteotomy of congenital kyphosis with at least 2-year follow up was analyzed retrospectively. Perioperative indicators such as operation time, osteotomy site, osteotomy method and occurrence of complications, and imaging indicators were observed. The 3D printed models were used to measure the expanded distance of anterior edge vertebra and closed length of spinal canal line. The clinical effect was evaluated through SRS-22 questionnaires. RESULTS: There were 15 CK patients in this study. The osteotomy segments and details are as follows: 1 case each for T6-9 and L2, 2 cases at T11, 3 cases at T12, and 6 cases at L1. The average operation time was 314 min, the average blood loss was 970 mL, the average fusion range was 6.3 segments, and the average time of follow up was 70.5 months. The Cobb angle of local kyphosis was corrected from 65.6 ± 18.8° to 11.3 ± 7.1°(p < .001). The range of kyphosis correction was 40-90°, and average correction rate was 83.2% (67.7-95.7%). The correction was stable in follow-up, and the kyphotic angle was 11.0 ± 7.6 (p = .68). The preoperative SVA was 31.5 ± 21.8 mm, and the postoperative recovery was 18.0 ± 15.5, while the last follow-up was 9.1 ± 7.9. The p values were 0.02 and 0.07 respectively. By using 3D printed models, the expanded distance of anterior edge vertebra and closed length of spinal canal line were 14.5 ± 7.5 mm and 24.5 ± 8.0 mm respectively. Self-image and satisfaction in SRS-22 improved significantly. There was no recurrence of deformity and junctional kyphosis. CONCLUSIONS: The posterior closing-opening wedge osteotom for treatment of congenital kyphosis in children is satisfactory, if selected appropriately. During the longitudinal follow-up, the patients could achieve solid fusion and the correction could be well maintained.Evidence of Confidence: IVa.

Comparison of Transfer Learning Models in Pelvic Tilt and Rotation Measurement in Pediatric Anteroposterior Pelvic Radiographs.

The rotation and tilt of the pelvis during anteroposterior pelvic radiography can lead to misdiagnosis of developmental dysplasia of the hip (DDH) in children. At present, no method exists for accurately and conveniently measuring the precise rotation and tilt angles of pelvic on radiographs. The objective of this study was to develop several rotation and tilt measurement models using transfer learning and digital reconstructed radiographs (DRRs), and to compare their performances on pelvic radiographs. Based on the inclusion criteria, 30 of 92 children who underwent 3D hip CT scans at Xijing Hospital from 2015 to 2020 were included in the study. Using DRR techniques, radiographs were generated by rotating and tilting the pelvis in CT datasets at - 12 to 12° (projected every 3°) and were randomized to a 2:1:1 ratio of training dataset, validation dataset, and test dataset. Five pre-trained networks, including VGG16, Xception, VGG19, ResNet50 and InceptionV3 were used to develop pelvic rotation measurement models and tilt measurement models, and these models were trained with training dataset. The callback function was used during the training to slow down the learning rate when learning was stalled. Then, the validation set was used to optimize each model and compare their performances. At last, we tested the final performances of optimal rotation measurement model and optimal tilt measurement model on test dataset. The mean absolute error (MAE) was employed to assess the performance of the models. A total of 2430 pelvic DRRs were collected based on 30 CT datasets. Among 5 pre-trained transfer learning models, VGG16-Tilt achieved the best tilt prediction performance at the same BS and different LR. VGG16-Tilt model achieved its best performance on validation set at LR = 0.001 and BS = 4, and the final MAE on the test set was 0.5250°. In terms of rotation prediction, VGG16-Rotation also achieved the best performance, and it achieved its best performance on validation set at LR = 0.002 and BS = 8. The final MAE of VGG16-Rotation on the test set was 1.0731°. Pretrained transfer learning models worked well in predicting tilt and rotation angles of the pelvis on radiographs in children. Among them, VGG16-Tilt and VGG16-Rotation had the best effect in dealing with such problems despite their simple structures. These models deployed in devices can give orthopedic surgeons a powerful aid in DDH diagnosis.

Therapeutic effect of minimally invasive catheter drainage and local chemotherapy for the lumbosacral tuberculosis without neural symptoms.

Increasing number of studies have shown growing incidence of lumbosacral tuberculosis and its complications. However, the treatment options for this disorder are still limited.To evaluate the long-term therapeutic effect and prognosis of minimally invasive puncture catheter drainage and Isoniazid local chemotherapy for the treatment of lumbosacral tuberculosis without neural symptoms under the guidance of computed tomography (CT).A total of 45 patients with asymptomatic lumbosacral tuberculosis were treated by minimally invasive catheter drainage under CT guidance. Forty-two cases had been followed up, which included 22 women and 20 men with an average age of 36.45 years old. Isoniazid was injected locally and antituberculotic drugs were administered for postoperative treatment. Oswestry Disability Index (ODI), visual analogue scale (VAS) evaluation and Cobb angle were recorded before and after operation.Forty-two patients had been followed up and the follow-up term was from 1.2 to 8.5 years (average 60 months). All patients were healed without recurrent cases. The ODI were improved from 14.86 ±â€Š2.02 before operation to 1.48 ±â€Š1.55 after operation. The post-operative (4.19 ±â€Š1.17) VAS score was improved compared to the pre-operative VAS score (0.55 ±â€Š0.55). The post-operative Cobb angle (6.19°â€Š±â€Š3.85°) was also improved relatively to the preoperative Cobb angle (5.90°â€Š±â€Š3.71°).Minimally invasive puncture catheter drainage combined with Isoniazid local chemotherapy is an effective method for lumbosacral tuberculosis without neural symptom. Meanwhile, it can be applied for the treatment of spinal tuberculosis before open surgery.

One-stage Surgical Treatment of Simultaneous Osteotomy and Asymmetric Lengthening on Short Femur with Severe Deformity of Genu Valgus.

This study aimed to discuss the effects of one stage surgical treatment by simultaneous osteotomy and asymmetric lengthening by Ilizarov external fixator on short femur with severe deformity of genu valgus. A total of 12 cases with unilateral deformities treated by simultaneous osteotomy and Ilizarov asymmetric lengthening on short femur with severe deformity of genu valgus were retrospectively analyzed from January 2006 to April 2015. The affected limbs were 2.5-11 cm (5.2 cm on average) short, the femorotibial angle was 135°-158° (146.3° on average), and the ankle interval was 15-43 cm (24.7 cm on average). The Paley method was used to determine the osteotomy plane (distal femur) of genu valgus. According to this standard, the bone union results were as follows: 11 had excellent and 1 had good, where 7 patients had excellent and 5 had good functional outcomes. One stage surgical treatment by simultaneous osteotomy and asymmetric lengthening on short femur with severe deformity of genu valgus was considered to be an effective and reliable method with better osteotomy union, less trauma and fewer complications.

Effects of arthroscopic-assisted surgery on irreducible developmental dislocation of hip by mid-term follow-up: An observational study.

The purpose of this study was to investigate the indications, surgical technique, and the clinical effects of arthroscopic-assisted treatment of irreducible developmental dislocation of the hip by mid-term follow-up. Arthroscopic-assisted surgeries were performed on 40 children (52 hips) between January 2005 and December 2009. Anterior and antero-superior greater trochanter portals were used in these treatments. Spica cast and abduction splint were applied for 3 months postoperatively. The follow-up was conducted on every 3 months postoperatively. During 12-month follow-up, a secondary treatment such as acetabuloplasty and/or femoral osteotomy (shortening, varus, and derotation) was applied if the acetabular angle was greater than 25°. The pelvic acetabular angle, Mckay and Severin score were evaluated every 6 months in all children. With 36 to 96 months (average 71 months) follow-up, 35 children (44 hips) were successfully followed up with complete case data while 5 children unsuccessfully. According to Tönnis classification, there were 5 grade 1 hips, 14 grade 2 hips, 14 grade 3 hips, 11 grade 4 hips, in which 3 children (4 hips) were failed in arthroscopic reduction and femoral head avascular necrosis occurred in 2 children (4 hips). According to Mckay standard, the good rate is 100%. According to Severin standard, the good rate is 84.1%. Arthroscopic assisted treatment is an effective way of reduction of the irreducible hip. Compared with the open reduction, arthroscopic treatment combined with acetabuloplasty and/or femoral osteotomy has advantages of less trauma and better function preservation.

[Effects of self-assembled IKVAV peptide nanofibers on olfactory ensheathing cells].

We observed the effects of IKVAV self-assembling peptide nanofiber scaffold (SAPNS) on olfactory ensheathing cells (OECs). The IKVAV molecules were triggered to self-assemble to interconnected nanofibers hydrogel by adjusting pH of solution and adding of DMEM/F12 culture medium. Atomic Force Microscopy (AFM) showed that self-assembly hydrogel was consisted of the interconnected nanofibers, which varied from three nm to five nm in diameter and hundreds nanometer in length. The primary OECs were isolated from rat olfactory bulb and purified by differential adhesion twice. At days 12, the purity of OECs was 85% according to immunostaining of P75 NGFR antibody. OECs were cultured with IKVAV peptide. The adhesion, viability and proliferation of OECs were observed with inverted microscope, Calcein-AM/PI staining and Cell Counting Kit-8. OECs cultured on IKVAV SAPNS grew well and the viable cell count was 95%. IKVAV SAPNS can promote the adhesion of OECs and did no hinder the proliferation of OECs. IKVAV SAPNS nanofiber gel has good biocompatibility and bioactivity for OECs. It can serve as a good nerve tissue engineering scaffold.