To investigate the effects of postoperative fusion implantation on the mesoscopic biomechanical properties of vertebrae and bone tissue osteogenesis in idiopathic scoliosis, a macroscopic finite element model of the postoperative fusion device was developed, and a mesoscopic model of the bone unit was developed using the Saint Venant sub-model approach. To simulate human physiological conditions, the differences in biomechanical properties between macroscopic cortical bone and mesoscopic bone units under the same boundary conditions were studied, and the effects of fusion implantation on bone tissue growth at the mesoscopic scale were analyzed. The results showed that the stresses in the mesoscopic structure of the lumbar spine increased compared to the macroscopic structure, and the mesoscopic stress in this case is 2.606 to 5.958 times of the macroscopic stress; the stresses in the upper bone unit of the fusion device were greater than those in the lower part; the average stresses in the upper vertebral body end surfaces were ranked in the order of right, left, posterior and anterior; the stresses in the lower vertebral body were ranked in the order of left, posterior, right and anterior; and rotation was the condition with the greatest stress value in the bone unit. It is hypothesized that bone tissue osteogenesis is better on the upper face of the fusion than on the lower face, and that bone tissue growth rate on the upper face is in the order of right, left, posterior, and anterior; while on the lower face, it is in the order of left, posterior, right, and anterior; and that patients’ constant rotational movements after surgery is conducive to bone growth. The results of the study may provide a theoretical basis for the design of surgical protocols and optimization of fusion devices for idiopathic scoliosis.
Objective To review the King-types Ⅲ and Ⅳ patients treated by the CD hybrid technique and evaluate clinical results on the shorter fusion levels. Methods Fifty-eight patients with idiopathic scoliosis were treated by the CD hybrid method from March 2000 to January 2003, among whom 40 were grouped as Kingtype Ⅲ and 18 as Kingtype Ⅳ; 41 were female and 17 were male. The Cobb angle of the thoracic curve was averaged 64°(range 50-83°), and the curve flexibility was 62%. The compensative lumbarcurve was averaged 37°（range 16-48°）, and the curve flexibility was 105%. With the neutral rotational vertebrae as a basis to select the low instrumentation vertebrae, the neutral rotational vertebrae or the vertebrae at 1 or 2 levelsproximal to the neutral rotational vertebrae were selected as the low instrumentation vertebrae in all the patients. Standing AP and lateral radiographs were taken respectively at the discharge, during the follow-up after discharge, and at the final follow-up. Results The patients were followed up for an average of 2.4 years (range 1.8-3.2). The corrected curves lost an average of 3.1°（range -1-5°）and the correction rate of the thoracic curve was 68% at the final follow-up.The plumbline from C7 was parallel to the sacral midline in 56 patients. The lumbar curves were corrected to an average of 8°（2-13°）automatically. The lumbosacral angle was corrected automatically by 53% and the low instrumentation vertebrae in 48 patients turned into stable vertebrae. The low instrumentation vertebrae lost 1.4 segments on average compared with the Harrington principle. No spinal imbalance was clinically observed in all the patients. Conclusion The choice of the low instrumentation vertebrae as the neutral rotational vertebrae can have a good result in the clinical practice. It can be applied in the CD hybrid technique in treatment of idiopathicthoracic curves.
ObjectiveTo explore the effect of a new rehabilitation intervention model based on International Classification of Functioning, Disability and Healthy (ICF) concept in perioperative treatment on patients with adolescent idiopathic scoliosis (AIS).MethodsFrom June 2017 to January 2019, AIS patients with Cobb angle below 80° were randomly divided into experimental group and control group by the method of randomized block design. The patients in the control group received routine perioperative rehabilitation intervention, while the patients in the experimental group received rehabilitation mode intervention based on ICF concept. The therapeutic effect of the two groups including functional and activity dimensions was observed.ResultsA total of 40 patients were included, with 20 in each group. Two patients withdrew the control group. On the fourth day after surgery, the total score of Modified Barthel Index (50.55±8.87 vs. 18.99±5.63; t=13.264, P<0.001) and Scoliosis Research Society-22 (SRS-22) (3.68±0.13 vs. 3.27±0.11; t=10.355, P<0.001) in the experimental group were all better than those in the control group. In the SRS-22 scores, statistically significant differences in comparison of function (2.79±0.29 vs. 1.90±0.48; t=6.884, P<0.001), and self image (3.91±0.27 vs. 3.38±0.32; t=5.539, P<0.001) between the two groups were found. There was no statistically significant difference in pain indicators and muscle strength between the two groups in the two postoperative evaluations (P>0.05). ConclusionsThe treatment based on the concept of ICF can improve the daily living ability in the short term with the safe and acceptable premise. The concept of stimulating patient autonomy, improving patient independence, and promoting social treatment, may improve the overall state of the patients.
ObjectiveTo identify the prevalence of distal adding-on phenomenon after posterior selective fusion in type Lenke 1A idiopathic scoliosis, to analyze its risk factors so as to find the reasonable choice for lowest instrumented vertebra (LIV). MethodsA retrospective study was made on the clinical data of 43 patients with type Lenke 1A idiopathic scoliosis undergoing posterior selection fusion with pedicle screw instrumentation between July 2011 and December 2015. There were 15 males and 28 females, aged 12-18 years (mean, 16 years). The preoperative Cobb angle was (50.1±11.3)°. The anteroposterior and lateral radiographs were taken at preoperation, immediate after operation, and last follow-up to measure the radiographic parameters. Forty-three patients were divided into adding-on group and control group according to whether or not the occurrence of distal adding-on phenomenon on anteroposterior radiographs of the spine at last follow-up. All the factors that maybe cause distsal adding-on were evaluated by statistical analysis. ResultsThe patients were followed up 12-50 months (mean, 26.5 months). At last follow-up, distal adding-on was observed in 10 of 43 patients (23.3%), including 2 males (13.3%) and 8 females (28.6%). Univariate analyses showed following several factors associated with adding-on:preoperative lumbar flexibility, preoperative pelvic tilt in coronal plane, preoperative LIV+1 deviation from center sacral vertical line, L4 subtype, the difference between LIV and last touching vertebra (LTV) (LIV-LTV), the difference between LIV and lower end vertebra (LEV) (LIV-LEV), and the difference between LIV and stable vertebra (SV) (LIV-SV). The risk factors above were brought into Logistic regression model, the results showed that preoperative LIV+1 deviation (deviation>10 mm, odds ratio=10.812, P=0.026), LIV-LTV (LIV-LTV<1, odds ratio=9.017, P=0.04), and L4 subtype (1A-R, odds ratio=9.744, P=0.047) were significantly associated with adding-on. ConclusionPreoperative LIV+1 deviation of >10 mm, L4 subtype (1A-R) and LIV-LTV of <1 are independent predictive factors of adding-on after surgery. As high risk of adding-on was closely related with the incorrect fusion level, it plays an important role for surgeons to decide the level of the fusion before surgery thoroughly. The LIV should be extended at least to LTV+1 to avoid adding-on phenomenon.
【Abstract】 Objective To study the short-term effects of thoracoscopic anterior spine release combined with posterior correction on the pulmonary function in patients with idiopathic scoliosis (IS). Methods Between April 2004 and June 2008, 21 cases of IS underwent thoracoscopic anterior spine release combined with posterior correction. There were 9 males and 12 females with a mean age of 15.6 years (range, 12 to 24 years). Of 11 patients, 2 had left protrusion deformity and 19 had right protrusion deformity, including 12 cases of Lenke type I and 9 cases of Lenke type II, with an average coronal Cobb’s angle of 79.6° (range, 65-125°). The disease duration ranged from 1 year and 6 months to 9 years (mean, 2.5 years). The results of pulmonary function tests (PFTs) were compared between pre-operation and postoperative 6th month, including lung capacity, ventilation function, and thoracic compliance. Results The opening time of the chest was 90 to 150 minutes (mean, 127 minutes) at the thoracoscopic anterior spine release and all incisions healed by first intention with no chest cavity infection. All the patients were followed up from 6 to 36 months (mean, 13.5 months). The average coronal Cobb’s angle was 43.7° (range, 36-75°) at 1 week after posterior correction. At 6 months after operation, the vital capacity and total capacity were significantly increased (P lt; 0.05), but no significant change was observed in the percentage of actual value and expected one when compared with pre-operation (P gt; 0.05). The functional residual capacity and the percentage of actual value and expected one of residual volume was significantly decreased when compared with those at pre-operation (P lt; 0.05). The forced expiratory volume in one second (FEV1) and FEV1/FEV were not significantly improved (P gt; 0.05) , but the maximum ventilatory volume was significantly increased when compared with the preoperative value (P lt; 0.05). In addition, the Raw Total, Raw Insp, and Raw Exp decreased significantly after operation (P lt; 0.05). Conclusion Although the thoracoscopic anterior spine release combined with posterior correction might disturb the function of the thoracic cavity, the PFTs of the patients could be improved at different aspects because of the shape changes of the thoracic cavity, and the pulmonary function still needed further observation.
Objective To compare the rib regeneration in patients with adolescent idiopathic scoliosis (AIS) after convex short length rib resection or conventional thoracoplasty. Methods Between January 2005 and December 2009, 36 patients with Lenke 1 AIS underwent posterior correction, instrumentation, and fusion, and the clinical data were retrospectively analyzed. Conventional thoracoplasty was performed in group A (n=14), convex short length rib resection in group B (n=22). There was no significant difference in gender, age, Cobb angle of major curve, flexibility, and preoperative rib hump between 2 groups (P gt; 0.05). The standing long-cassette anteroposterior and lateral X-ray films of spine were taken at 3 months, 6 months, l year, and 2 years respectively after operation. Rib regeneration classification established by Philips was used to analyze the rib formation. Results All patients were followed up 32 months on average (range, 24-48 months). Cobb angle of major curve and rib hump were significantly improved when compared with preoperative values in 2 groups (P lt; 0.05), and there was no obvious correction loss. At each time point after operation, there was no significant difference in Cobb angle of major curve between 2 groups (P gt; 0.05), but the rib humb of group B was significantly bigger than that of group A (P lt; 0.05). The rib regeneration in group B was better than that in group A, showing significant difference (P lt; 0.05). At 3 months after operation, 80.0% rib regeneration was below grade 4 in group A, and 96.3% rib regeneration reached grade 4 or above in group B. At 2 years after operation, 52.0% and 96.3% rib regeneration reached grade 6 or above in groups A and B, respectively. Conclusion The rib regeneration in patients with AIS after convex short length rib resection is better than that after conventional thoracoplasty.
ObjectiveTo develop a smart orthosis personalized management system for the treatment of patients with adolescent idiopathic scoliosis (AIS) and to evaluate the feasibility and efficiency through clinical preliminary applications.MethodsThe smart orthosis personalized management system consists of a wireless force monitor, a WeChat Mini Program, a cloud-based storage system, and a website backstage management system. Twenty-two patients with AIS who underwent orthosis treatment and met the selection criteria between March 2020 and December 2020 were enrolled. The follow-up time was 4 months. The parameters used to evaluate patients’ compliance were as follows (back and lumbar): baseline force value, measured force value, force compliance (measured force value/baseline force value×100%), measured wearing time (wearing time of force value was more than 0 N), and time compliance (measured wearing time/prescribed wearing time×100%), in which the prescribed wearing time was 23 hours/day. The baseline force values were measured at initiation, while the measured force value, measured wearing time, force compliance, and time compliance were measured during follow-up. The differences of these parameters between back and lumbar, and the differences among these parameters at 1, 2, 3, and 4 months after orthosis wearing were analyzed.ResultsThe average measured force value of 22 patients (back and lumbar) was (0.83±0.34) N, the average force compliance was 68.5%±17.9%, the average measured wearing time was (15.4±1.7) hours, and the average time compliance was 66.9%±7.7%. The baseline force value and measured force value of back were significantly higher than those of lumbar (P<0.05); the measured wearing time, force compliance, and time compliance between back and lumbar showed no significant difference (P>0.05). The measured force value, measured wearing time, force compliance, and time compliance at 1 month after wearing were significantly lower than those at 2, 3, and 4 months after orthosis wearing (P<0.05), no significant difference was found among 2, 3, and 4 months after orthosis wearing (P>0.05). At different time points after wearing, the measured force value of back were significantly higher than that of lumbar (P<0.05), while there was no significant difference between back and lumbar on the other parameters (P>0.05).ConclusionThe smart orthosis personalized management system has high feasibility to treat AIS, and can improve the compliance of such patients with orthosis wearing.
In order to investigate the mechanical response of lumbar vertebrae during gait cycle in adolescents with idiopathic scoliosis (AIS), the present study was based on computed tomography (CT) data of AIS patients to construct model of the left support phase (ML) and model of the right support phase (MR), respectively. Firstly, material properties, boundary conditions and load loading were set to simulate the lumbar vertebra-pelvis model. Then, the difference of stress and displacement in the lumbar spine between ML and MR was compared based on the stress and displacement cloud map. The results showed that in ML, the lumbar stress was mostly distributed on the convex side, while in MR, it was mostly distributed on the concave side. The stress of the two types of stress mainly gathered near the vertebral arch plate, and the stress of the vertebral arch plate was transmitted to the vertebral body through the pedicle with the progress of gait. The average stress of the intervertebral tissue in MR was greater than that in ML, and the difference of stress on the convex and convex side was greater. The displacement of lumbar vertebrae in ML decreased gradually from L1 to L5. The opposite is true in MR. In conclusion, this study can accurately quantify the stress on the lumbar spine during gait, and may provide guidance for brace design and clinical decision making.
Objective To investigate the effectiveness of multilevel Ponte osteotomies on maintenance and restoration of thoracic kyphosis in idiopathic scoliosis (IS) surgery. Methods Between March 2008 and February 2010, 42 patients with thoracic IS (Lenke type 1 curves) were corrected with posterior pedicle screw system. Multilevel Ponte osteostomies for posterior release was performed in 17 cases (group A), and the 3 segments near the apical vertebrae were selected as the osteotomy site; simple posterior soft tissue release was given in 25 cases (group B). There was no significant difference in sex, age, disease duration, lesion segments, coronary Cobb angle, thoracic kyphosis, Risser index, and bending flexibility between 2 groups (P gt; 0.05). The anteroposterior and lateral standing radiographs of the spine were taken to compare the effectiveness between 2 groups. Results Operation was successfully completed in all patients. The operation time and blood loss in group A were significantly greater than those in group B (P lt; 0.05). Spine dural injury and leakage of cerebrospinal fluid occurred in 1 case of group A, which was cured after compression on local area of the wound; the other patients had no intraoperative complications. The patients were followed up 2-4 years (mean, 2.8 years); no nerve injury, infection, or internal fixation failure occurred. No obvious correction loss was observed and the appearance and trunk balance were significantly improved. The coronal Cobb angles at 1 week and 2 years after operation were significantly improved when compared with preoperative ones in 2 groups (P lt; 0.05). There was no significant difference in the coronal Cobb angle and correction rate between 2 groups at 1 week and 2 years after operation (P gt; 0.05). Group A was significantly better than group B in the thoracic kyphotic angle and angle changes at 1 week and 2 years after operation (P lt; 0.05). Conclusion The posterior approach surgery with multilevel Ponte osteotomies can restore the thoracic kyphosis in IS, but it has no effect on coronal correction in Lenke type 1 curves.