Background Three-dimensional (3-D) printing offers the opportunity to create patient-specific guides for pedicle screw placement based on CT-generated models. This technology might allow for more-accurate placement of pedicle screws in patients with severe congenital scoliosis who have rotated vertebrae and small pedicles, but to our knowledge, this premise has not been tested. Questions/purposes (1) Is the use of 3-D printing and pedicle guider technology as or more accurate than the use of the freehand technique for pedicle-screw placement in patients with severe congenital scoliosis? (2) Does surgical time differ with the use of these guiders? (3) Are complications less common in patients treated with this new approach to pedicle-screw placement? Methods A prospective controlled study was conducted of patients with severe congenital scoliosis (major curve ≥ 90°) from June 2016 to June 2018. During this period, we treated 93 patients with congenital scoliosis; 32 had severe scoliosis with a major curve ≥ 90°. The patients were divided into a pedicle guider group (n = 15) and a control group (n = 17) based on their willingness to use pedicle guider technology, which was considered a research technology. With the numbers available, there were no between-group differences in terms of age, sex, BMI, or parameters related to curve severity or flexibility, and all patients in both groups had severe curves. Preoperative and postoperative low-dose CT scans were performed in the two groups. In the pedicle guider group, custom software was used to design the pedicle guider, and a 3-D printer was used to print a physical spinal model and pedicle guiders. The pedicle guiders were tested on the surface of the physical spinal model before surgery to ensure proper fit, and then used to assist pedicle screw placement during surgery. A total of 244 screws were implanted with the help of 127 pedicle guiders (254 guiding tunnels) during surgery in the PG group. Five predesigned pedicle guiders were abandoned due to an unstable match, and the success rate of assisted screw placement using a pedicle guider was 96% (244 of 254). The freehand technique was used in the control group, which relied on anatomic localization to place pedicle screws. The accuracy of pedicle screw placement was evaluated with CT scans, which revealed whether screws had broken through the pedicle cortex. We compared the groups in terms of accuracy (defined as unanticipated breaches less than 2 mm), surgical time, time to place pedicle screws, and screw-related complications. Results A higher proportion of the screws placed using pedicle guider technology were positioned accurately than were in the control group (93% [227 of 244] versus 78% [228 of 291]; odds ratio, 3.69 [95% CI, 2.09–6.50]; p<0.001). With pedicle guider use, operative time (296 ± 56 versus 360 ± 74; 95% CI, -111 to -17; p = 0.010), time to place all screws (92 ± 17 versus 118 ± 21; 95% CI, -39 to -12; p = 0.001), and mean time to place one screw (6 ± 1 versus 7 ± 1; 95% CI, -2 to 0; p = 0.011) decreased. One patient in the pedicle guider group and four in the control group experienced screw-related complications; the sample sizes and small number of complications precluded statistical comparisons. Conclusions In this small, preliminary study, we showed that the accuracy of the surgical technique using spinal 3-D printing combined with pedicle guider technology in patients with severe congenital scoliosis was higher than the accuracy of the freehand technique. In addition, the technique using pedicle guider technology appeared to shorten operative time. If these findings are confirmed in a larger study, pedicle guider technology may be helpful for situations in which intraoperative CT or O-arm navigation is not available. Level of Evidence Level II, therapeutic study.

Tumefactive demyelinating lesions (TDLs) are misdiagnosed frequently. To investigate the characteristics of TDLs, clinical and radiological data from nine cases with TDLs were analyzed after admission. All cases underwent surgery and pathological examination; some received postoperative steroid therapy. Onsets were mostly within 3 weeks and main presentation included intracranial hypertension, extremity weakness, epilepsy, and visual disturbance. Symptoms in children were acute and severe, frequently including headache, vomiting, and visual disturbance. Most intracephalic lesions were in cerebral hemispheres. All intraspinal lesions were in cervical segments. Radiological features included mass effect, perifocal edema and enhancement (of which open-ring enhancement was diagnostic), and decreased relative cerebral blood volume. Intraoperative frozen section did not confirm the diagnosis, while postoperative paraffin section did confirm it (by evidence of macrophage infiltration). The patients responded well to steroid therapy and no relapse was found during following up. Thus, intensive analysis of both clinical and radiological data may provide some clues for diagnosis. For suspected cases, it is advisable to take steroid therapy or undergo advanced radiological examinations, such as serial magnetic resonance spectroscopy. However, in difficult cases, pathological evidence is beneficial to a final diagnosis.

It is important to establish an efficient vascularization for the long-term acceptance of bioengineered skin equivalents treating the cutaneous wounds of diabetic rats with hindlimb ischemia. This study investigates the possible use of a collagen-chitosan sponge scaffold encapsulated with thymosin beta 4 (CCSS-eTβ4), an angiogenic factor, to accelerate cutaneous wound healing in streptozotocin (STZ)-induced diabetic rats with hindlimb ischemia. CCSSs-eTβ4 was fabricated using a freeze-drying method. The scaffolds were analyzed by scanning electron microscopy, swelling and degradation assays, mechanical properties, and scaffolds of 50:50 collagen-chitosan were selected and applied. The controlled release of Tβ4 from the scaffolds elicited localized and prolonged effects over 12 days, as shown by an enzyme-linked immunosorbent assay (ELISA). In vivo, CCSSs-eTβ4 improved diabetic cutaneous wound healing, with faster wound reepithelialization, better dermal reorganization, and higher wound vascularization. Furthermore, CCSSs-eTβ4 downregulated inflammatory genes and upregulated angiogenic genes in the wound tissue. Significant increases in CD31-positive endothelial cells and new vessel density were also observed. In vitro, Tβ4 increased the migratory and proliferative activity of high glucose (HG)-treated human umbilical vein endothelial cells (HUVECs). Meanwhile, we found that Tβ4 could promote HG-treated HUVECs migration and improve angiogenesis by activation of the VEGF/AKT pathway. Overall, these findings demonstrated the promising potential of CCSSs-eTβ4 to promote more effective wound healing and suggest its possible application for diabetic cutaneous wound treatment.