【Abstract】 Objective To explore the methods and appl ication value of surface shaded display (SSD) and multiplanarreconstruction (MPR) in the evaluation of acetabular morphology in patients with developmental dysplasia of the hip (DDH) before total hip arthroplasty (THA). Methods From October 2003 to November 2006, 17 patients (3 males and 14 females, aging from 35 years to 61 years) with osteoarthritis secondary to DDH were scanned with spiral CT preoperatively. According to the Crowe standard, 19 dysplasia hips were classified as type I in 4 hips, type II in 9 hips, type III in 6 hips. The obtained hip CT data were developed with SSD and MPR to observe spational position and bone stock of the acetabula. Results The dislocated extent was 25%-89% in these dysplasia hips according to the Crowe method and their sharp angles all exceeded 45°. Bone defect occurred to each of the acetabula, among which it was located in anterosuperior acetabulum in 5 hips, in superolateral acetabulum in 11 hips and in posterosuperior acetabulum in 3 hips. The hip images made with MPR showed that the minimum thickness of the medial wall of acetabula ranged from 2.0 mm to 10.9 mm. Among 15 unilateral dysplasia patients, the opening difference anddepth difference between the dysplasia acetabulum and the contralateral one ranged from 2.7 mm to 19.1 mm and from 2.3 mm to 13.1 mm, respectively. Conclusion SSD and MPR of spiral CT are effective methods in evaluating acetabular morphology preoperation and contribute to intraoperative acetabular reconstruction in patients with DDH performed THA.
Objective To study the healing ability of the central area tissue of flexor tendons after injury. Methods Tendons of flexor digitorum profundus of the long toes from 8 white Leghorn hens were harvested in zone II. Tissues were cut in 4 mm segments and divided into the experimental group(the central area tissue of flexor tendons) and the control group(the tendon segments without epitenon). There were 12 tendon segments cultured in each group. Specimens were obtained and examined under light microscope on the 9th, 18th and 27th days after culture, respectively. Another 4 tendons were used as normal control, and they were directly examined under light microscope. Results The number of tenocytes was significantly less in the control group than in the experimental group and the uncultured state (P＜0.01); the number of tenocytes was significantly higher in the experimental group than in the uncultured state (P＜0.01). The number of tenocytes of the experimental group were higher on the 9th day than on the 18th and 27th days after culture(P＜0.01). Conclusion The central area tissue of flexor tendons has favorable healing ability after injury.
OBJECTIVE: To establish the animal models of mandibular distraction osteogenesis in rabbits and study its osteogenetic mechanism. METHODS: The right mandibles just anterior to the first molars of 12 rabbits were performed osteotomies, and the mandibles were positioned with distractors. The left mandibles were control group without operation. After 1 week, the distractors were stretched 0.9 mm every day for 10 days progressively. One day, 2, 4, 8 weeks after distraction, the mandibles were studied with gross measurement, X-ray, and histological examination. RESULTS: The right mandible were lengthened 8.3 mm on average without bone nonunion and deformity healing. It was observed that the gaps between the distracted bone edges were first occupied by fibrous tissue. Two weeks after distraction, it was found that the gaps were bridged by callus in X-ray, the new bone and the normal bone could not be differentiated clearly after 8 weeks. In histological sections, there were collagen bundles in early distraction, then those collagen bundles were calcificated and become trabeculaes. No Cartilage was found during distraction. CONCLUSION: It suggests that the rabbit mandible can be lengthened by distraction osteogenesis, and the new bone is formed by intramembranous ossification.
In order to investigate the histological and stereological change of the rapidly expanded skin tube, 15 Japanese Long Ear Rabbits were divided into 3 groups: (1) Rapid expansion group, injecting once a day for 7 days; (2) Routine expansion group, injecting every 3 days for 21 days and (3) Control group, no expander implanted. The results showed that: in the rapid expansion group, the thickness of the epidermis and dermis were both increased, fibroblast proliferation was active, a large amount of new capillaries was observed, the collagen fiber was in loose type, and the mitochondria and rough endoplasmic net of epithelial cell were increased. In the routine expansion group, similar changes were observed. The vascular density and volume fraction were significantly higher in rapid expansion group than those in the control group (P lt; 0.05). It was concluded that the rapid expansion of skin tube was feasible.
In this work, a new method of heart sound signal preprocessing is presented. First, the heart sound signals are decomposed by using multilayer wavelet transform. And then double parameters as thresholds are used in processing each layer after decomposition for denoising. Next, reconstruction of heart sound signals could be done after processing last layer. Four methods, i.e. wavelet transform, Hilbert-Huang transform (HHT), mathematical morphology, and normalized average Shannon energy, were used to extract the envelop of the heart sound signals respectively after reconstruction of heart sounds. All methods were improved in this study. We finally in our study chose 30 cases of raw heart sound signals, which were selected randomly from a database comed from The Clinical Medicine Institute of Montreal, and processed them by using the improved methods. The results were satisfactory. It showed that the extracted envelope with the original signal has a high degree of matching, whether it is a low frequency portion or high frequency portion. Most of all information of heart sound has been maintained in the envelope.
Characteristics in pulse wave signals (PWSs) include the information of physiology and pathology of human cardiovascular system. Therefore, identification of characteristic points in PWSs plays a significant role in analyzing human cardiovascular system. Particularly, the characteristic points show personal dependent features and are easy to be affected. Acquiring a signal with high signal-to-noise ratio (SNR) and integrity is fundamentally important to precisely identify the characteristic points. Based on the mathematical morphology theory, we design a combined filter, which can effectively suppress the baseline drift and remove the high-frequency noise simultaneously, to preprocess the PWSs. Furthermore, the characteristic points of the preprocessed signal are extracted according to its position relations with the zero-crossing points of wavelet coefficients of the signal. In addition, the differential method is adopted to calibrate the position offset of characteristic points caused by the wavelet transform. We investigated four typical PWSs reconstructed by three Gaussian functions with tunable parameters. The numerical results suggested that the proposed method could identify the characteristic points of PWSs accurately.
In order to improve the interfacial bonding strength of hydroxyapatite/polyurethane implanted material and dispersion of hydroxyapatite in the polyurethane matrix, we in the present study synthesized nano-hydroxyapatite/polyurethane composites by in situ polymerization. We then characterized and analyzed the fracture morphology, thermal stability, glass transition temperature and mechanical properties. We seeded MG63 cells on composites to evaluate the cytocompatibility of the composites. In situ polymerization could improve the interfacial bonding strength, ameliorate dispersion of hydroxyapatite in the properties of the composites. After adding 20 wt% hydroxyapatite into the polyurethane, the thermal stability was improved and the glass transition temperatures were increased. The tensile strength and maximum elongation were 6.83 MPa and 861.17%, respectively. Compared with those of pure polyurethane the tensile strength and maximum elongation increased by 236.45% and 143.30%, respectively. The composites were helpful for cell adhesion and proliferation in cultivation.
ObjectiveTo study the effect of titanium particles on the proliferation, differentiation, and cytomorphology of osteoblasts, and to explore the possible internal relations and mechanism. MethodsCalvarial osteoblasts were separated from 10 newborn Sprague Dawley rats by repeated enzyme digestion, and were cultured in vitro. The cells were identified by alkaline phosphatase (ALP) staining and alizarin red staining. The cells at passage 3 were cultured with titanium particles culture medium at concentrations of 0.01, 0.05, 0.1, 0.5, and 1 mg/mL (0.01, 0.05, 0.1, 0.5, and 1 mg/mL groups). The absorbance (A) values were detected by cell counting kit 8 at 7 days after cultured to compare the effect of titanium particles at different concentrations on proliferation, and median lethal concentration was screened out. The expression of collagen type I was detected by ELISA to observe the effect of titanium particles on differentiation. The osteoblasts co-cultured with titanium particles of median lethal concentration (experimental group) for 7 days, and double fluorescence staining with FITC-phalloidine and propidium iodide was performed. The cytomorphology variation of osteoblasts after swallowing titanium particles was observed under laser scanning confocal microscope. The osteoblasts at passage 3 cultured with culture medium without titanium particles served as control group. ResultsThe cultured cells were identified as osteoblasts by ALP staining and alizarin red staining. Different concentrations of titanium particles could inhibit osteoblasts proliferation and differentiation in varying degrees, showing significant difference when compared with the control group at 7 days after culture (P<0.05). The cell proliferation and differentiation were decreased with increased titanium particles concentration; significant differences were found between the other groups (P<0.05) except 0.01 and 0.05 mg/mL groups (P>0.05). The median lethal concentration of titanium particles was 0.5 mg/mL. Laser scanning confocal microscope showed cellular shrinking, microfilaments distortion, pseudopodia contraction of osteoblasts that swallowed titanium particles in the experimental group. ConclusionTitanium particles can inhibit proliferation and differentiation of osteoblasts. The effect may be related to variation of cytomorphology after swallowing titanium particles.
ObjectiveTo objectively evaluate the effectiveness of the ventricular fold pull-down combined with strip myofascial flap to repair laryngeal defect after early glottic carcinoma operation with glottic morphological parameters and voice parameters. MethodsBetween January 2008 and December 2012, 47 patients with early glottic carcinoma and anterior commissure involvement underwent partial laryngectomy. All patients were male, aged from 60 to 75 years (mean, 68.5 years). The disease duration was 4-11 months (mean, 7.2 months). According to American Joint Committee on Cancer (AJCC) TNM criteria, 28 cases were classified as T1aN0M0, 14 cases as T1bN0M0, and 5 cases as T2N0M0. Laryngeal defect after resection of tumor was repaired by ventricular fold pull-down combined with strip myofascial flap. At 1 day before operation and at 1 year after operation, multilayer spiral CT was used to scan larynx, to measure and compare the anteroposterior diameter of vocal area, the distance between both sides of the vocal process, and the thickness of soft tissue of vocal area, and the effect of combined soft tissue flap was objectively assessed in laryngeal morphology reconstruction. The actual voice parameters[including F0, Jitter, Shimmer, normalized noise energy (NNE), and maximum phonatory time (MPT)] were tested and compared, and the effect of the combined soft tissue flap on postoperative laryngeal pronunciation was evaluated. ResultsPostoperative pathological examination revealed well-differentiated squamous cell carcinoma in 38 cases, and moderately-differentiated squamous cell carcinoma in 9 cases; no tumor was found in the resection margin. Healing of neck incision was obtained in all patients at 7-9 days after operation. Forty-four cases were decannulated at 9-11 days after operation and the remaining 3 cases were decannulated at 3 weeks after operation. Oral feeding usually started in all cases at 3-4 days after operation. All patients were followed up 1 year. At 1 year after operation, the anteroposterior diameter of vocal area was significantly reduced when compared with preoperative one (t=15.161, P=0.000); the distance between both sides of the vocal process and the thickness of soft tissue of vocal area had no significant changes (P > 0.05). Compared with preoperative ones, there were significant differences in Shimmer, NNE, and MPT (P < 0.05), but no significant difference was found in F0 and Jitter (P > 0.05) at 1 year after operation. ConclusionVentricular fold pull-down combined with strip myofascial flap can repair laryngeal defect effectively after partial laryngectomy and maintain the effective airway after operation. It not only has no effect on postoperative laryngeal morphology, but also can be used as new laryngeal voice vibration body.
ObjectiveTo investigate the impact of the Salter innominate osteotomy on the acetabular morphology and direction and the relationship between them in children with developmental dislocation of the hip (DDH) by three-dimensional CT. MethodsBetween January 2013 and January 2015, 51 patients with unilateral DDH were treated. All patients were females with an average age of 2 years and 5 months (range, one year and 6 months to 5 years). All the patients underwent open reduction of the hip, Salter innominate osteotomy, proximal femoral osteotomy, and hip cast immobilization for treatment. The data of three-dimensional CT before surgery and at 1 week after surgery were measured and collected as follows:the anterior acetabular index (AAI), posterior acetabular index (PAI), axial acetabular index (AxAI), acetabular anteversion angle (AAA) of the acetabulum, and the distances of the forward, outward, and lateral rotation of the distal osteotomy fragments. The differences of AAI, PAI, AxAI, AAA between before and after surgeries were compared and the difference values of the data with significant difference results were calculated. The relationship between the difference values and the distances of three different rotation directions before and after surgeries were tested by Spearman correlation analysis. ResultsThere were significant differences in the AAI, PAI, and AAA between before and after surgery (P<0.05), but no significant difference was found in the AxAI between before and after surgery (t=0.878, P=0.384). The difference values of AAI, PAI, and AAA were (4.518±4.601), (4.219±6.660), and (3.919±4.389)° respectively. The distances of the outward, lateral, and forward rotation of the distal osteotomy fragments after surgery were (0.420±0.339), (2.440±0.230), and (0.421±0.311) cm. There was a significant correlation between the three different rotation directions and AAI difference (P<0.05), especialy the outward rotation (r=0.981). There was a correlation between the outward, forward rotation and PAI, AAI differences (P<0.05), and no significant correlation between the lateral rotation and PAI, AAA was found (P>0.05). There was a significant correlation between the forward rotation and AAA difference (r=0.841). ConclusionSalter innominate osteotomy can increase the curvature of the anterior wall of the acetabulum in DDH, but reduce the curvature of the rear wall. At the same time, it can also change the direction of the acetabulum, significantly decrease the acetabular anteversion, but it can not change the depth of the acetabulum. The main factors of the curvature change after Salter innominate osteotomy of DDH is attributable to outward rotation, followed by forward rotation, and the main factor of the acetabular direction change is attributable to forward rotation.