Determination of silver content in silver-loaded coral hydroxyapatite in relation to the biocompatibility / 南方医科大学学报

<p><b>OBJECTIVE</b>To determine the amount of silver in silver-loaded coral hydroxyapatite (Ag(+)-CHA) bone substitute and its impact on the biocompatibility of this material with mouse embryonic osteoblast cells.</p><p><b>METHODS</b>Ag(+)-CHA was prepared by immersing coral hydroxyapatite in a serial concentration of silver nitrate solutions. The amount of silver in the prepared Ag(+)-CHA was measured by inductively coupled plasma atomic emission spectrometry (ICP-AES). The viability of MC3T3-E1 cells incubated with Ag(+)-CHA was measured by MTT colorimetric assay, and the cell growth and morphological changes were observed by inverted phase-contrast microscope and confocal laser scanning microscope.</p><p><b>RESULTS</b>The amount of silver loading in the bone substitutes prepared by immersion in 1×10(-2), 1×10(-3), 5×10(-4), 10(-4), 8×10(-5), and 5×10(-5) mol/L silver nitrate solutions were 4127.67∓47.35, 167.90∓11.00, 83.42∓4.51, 30.20∓2.32, 22.39∓4.09, and 15.11∓0.55 µg/g, respectively. A low silver content in the material (prepared with silver nitrate solution of less than 8×10(-5) mol/L) showed no significant inhibitory effect on the growth of MC3T3-E1 cells or produced noticeable cytotoxic effect. On the materials prepared with 8×10(-5) and 10(-5) mol/L silver nitrate solution, the osteoblasts displayed active proliferation similar to those incubated on materials without silver loading. The confluent cells showed a normal fusiform morphology with tight arrangement.</p><p><b>CONCLUSION</b>Ag(+)-CHA with low silver content has a good biocompability and can promote the proliferation and growth of MC3T3-E1 cells in vitro, suggesting the clinical potential of this material as a anti-infection bone substitute.</p>

Risk factors for postoperative pulmonary complications following transoral operation for the atlanta-axis disorders / 中华外科杂志

<p><b>OBJECTIVE</b>to evaluate the risk factors for postoperative pulmonary complications following transoral operation for the atlanta-axis disorders.</p><p><b>METHODS</b>total 104 cases were collected from January 2005 to June 2009. Twelve variables among patients with PPCs and without PPCs were analyzed by logistic regression analysis.</p><p><b>RESULTS</b>the incidence of postoperative pulmonary complications following transoral operation for the atlanta-axis disorders was 22.1% (23/104). There was significantly difference in 9 variables between patients with PPCs and without PPCs, and 5 variables as serum albumin < 35 g/L (OR = 15.185, P = 0.003), tracheotomy (OR = 32.254, P = 0.015), Frankle grade (OR = 8.866, P = 0.001), the duration of intubation > 4 d (OR = 7.934, P = 0.002), the duration of surgery > 6 h (OR = 16.889, P = 0.006) were found to be significantly related to the development to postoperative pulmonary complications by multivariate analysis.</p><p><b>CONCLUSION</b>serum albumin < 35 g/L, tracheotomy, Frankle grade, the duration of intubation > 4 d, the duration of surgery > 6 h are the risk factors for postoperative pulmonary complications following transoral operation for the atlanta-axis disorders.</p>

Diagnosis and treatment for complicated atlantoaxial dislocation / 中华外科杂志

<p><b>OBJECTIVE</b>To explore the clinical characteristics and treatment methods for complicated atlantoaxial dislocation.</p><p><b>METHODS</b>A retrospective evaluation was done to summarize and analyze the clinical characteristics and complicated factors of 54 patients with complicated atlantoaxial dislocation who could not to be treated effectively by using conventional therapy in our hospital from February 2005 to October 2008. According to different complicated factors, different treatment methods mainly including transoral atlantoaxial reduction plate-III (TARP-III) operation, decompression procedure with deep grinding guided by computer aided design-rapid prototyping (CAD-RP), screw placement technique with CAD-RP guide plate and extensile approach surgery were performed.</p><p><b>RESULTS</b>The average follow-up period was 24 months. Among 54 cases, 48 cases achieved immediate anatomic reduction completely and 6 cases almost achieved anatomical reduction. All the compressed spinal cords were decompressed sufficiently. The decompression rate was 86.0% and the improvement rate of nerve function was 77.8%. Two cases suffered postoperative intracranial infection.</p><p><b>CONCLUSION</b>Some cases of complicated atlantoaxial dislocation can be effectively treated by using TARP-III operation, decompression procedure with deep grinding guided by CAD-RP, individualized screw placement technique with CAD-RP guide plate and extensile approach surgery.</p>

Impact of muscle strength on knee joint stability in static loading / 南方医科大学学报

<p><b>OBJECTIVE</b>To study the in vivo stability of normal and anterior cruciate ligament (ACL)-injured knee joint before and after epidural anesthesia under 134 N pre-loading and evaluate the influence of muscular tension on the knee stability.</p><p><b>METHODS</b>Eight volunteers with unilateral ACL rupture and normal contralateral knee were enrolled in this study. CT (3D) images and 2 orthogonal images of the knee were captured at 0°, 30°, 60°, and 90° under 134 N pre-loading. The orthogonal images were used to recreate the in vivo knee positions at each of the targeted flexion angles by 2D/3D registration to analyze the tibial translation data.</p><p><b>RESULTS</b>The anterior tibia translation of both the intact and ACL-injured knees after anesthesia was significantly different from that before anesthesia at all the angles (P<0.05). The anterior tibial translation of the intact knee after anesthesia increased by 1.7 mm at 0°, 2.7 mm at 30°, 2.6 mm at 60°, and 2.3 mm at 90°, as compare to the increase of ACL-injured knee by 4.2 mm, 2.6 mm, 1.2 mm, and 1.6 mm, respectively.</p><p><b>CONCLUSION</b>The muscular tension has evident influence on the knee stability in static loading.</p>

Treatment of traumatic intervertebrae disk herniation in cervical thoracic junction through transforminal approach / 中国骨伤

<p><b>OBJECTIVE</b>To investigate the treatment for traumatic intervertebrae disk herniation in cervical thoracic junction.</p><p><b>METHODS</b>From 2003 to 2008, there were 10 patients with trautimatic intervertebral disk herniation in cervical thoracic junction, which included 6 males and 4 females, aged from 23 to 66 years (means 41.5 years). All of them were performed through the transforminal approach combined with internal fixation. After operation all patient underwent hyperbaric oxygen treatment. The function of spine was evaluated by JOA score system.</p><p><b>RESULTS</b>All patients were followed up for 8 to 16 months(means 13 months). All patients got recovery of spine function to some extent except one case with complete spine damaged. The JOA scores was improved from (8 +/- 3) before operation to (15 +/- 2) after operation.</p><p><b>CONCLUSION</b>Early and effective treatment by transforminal operation could be helpful for the recovery of spine function.</p>

In vitro drug release from a mitomycin C delivery system and its effect against scar tissue adhesion in vivo / 南方医科大学学报

<p><b>OBJECTIVE</b>To develop a chitosan (CH)/polyethylene glycols succinate acid (PEG-SA)-mediated mitomycin C (MMC) delivery system and investigate its drug release characteristics in vitro and its effect against scar tissue adhesion in vivo.</p><p><b>METHODS</b>Mitomycin C loading in the composite CH/PEG-SA/MMC films was determined using ultraviolet. The freeze-dried films were dispersed in 1 ml PBS (pH7.4) and mitomycin C release in vitro was determined according to the mitomycin C concentration-UV value standard curve. The influence of the film structure on the drug release was evaluated. The drug delivery system was then implanted in SD rats, and 4 weeks later, immunohistochemical and histological examinations were carried out to assess the therapeutic effect on epidural scar tissue.</p><p><b>RESULTS</b>The linear regression equation of the mitomycin C concentration-UV value standard curve was y=0.593x(3)-2.563x(2)+25.944x-0.236 (R(2)=1.000). The film demonstrated good drug delivery capability, and 20 mg of the samples in PBS showed a peak mitomycin C release after 12 days of 14.9616 microg/ml, which was higher than the ID(50) of mitomycin C (10.4713 microg/l) to the fibroblasts. On days 18 and 32, another two drug release peaks occurred (14.4824 microg/ml and 11.4092 microg/ml, respectively), followed by maintenance of slow release. Till day 60, the accumulative mitomycin release reached 0.1793 microg/ml, and the loaded drug was ultimately completely released. Significant differences were noted in the hydroxyproline content in the scar tissues of different groups (F=12.085, P=0.000), and the CH/PEG-SA/MMC DDS reduced the amount of scar tissue and promoted its orderly alignment to control potential scar hyperplasia that may compress the spinal cord and nerve roots.</p><p><b>CONCLUSION</b>The composite film for drug delivery possesses good flexibility and mechanical properties and allows sustained drug release of mitomycin C to prevent epidural scar tissue adhesion following lumbar laminectomy.</p>

The synthetic typing and its clinical application in atlantoaxial dislocation / 中华外科杂志

<p><b>OBJECTIVE</b>To evaluate the synthetic typing and the treatment strategy for atlantoaxial dislocation.</p><p><b>METHODS</b>The synthetic typing of atlantoaxial dislocation was worked out on the base of pathogenesis typing, Fielding imaging typing, and clinical typing, named PIR typing system (Pathogenesis, Imaging, and Reduction). Ninety-three patients with atlantoaxial dislocation were treated according to this typing system.</p><p><b>RESULTS</b>Nine cases of type-II dens fracture were treated with hollow screw fixation. Bone union was accomplished at the follow-up of three months in all the patients, only with slight limitation of cervical motion. Un-retrieved Fielding I -degree dislocation was found in one case. Among the thirty-four patients treated with trans-oropharyngeal atlantoaxial reduction plate system (TARP), 32 obtained complete atlantoaxial reduction and fusion three months after operation. Atlantoaxial dislocation recurred in the other two cases because of screw loosening and the problem was solved through revision operations. Four patients in non-reducible type underwent anterior and/or posterior decompression. T heir neurological improved after operation but their atlantoaxial joints remained dislocated, and one case complicated with intracranial infection.</p><p><b>CONCLUSIONS</b>Via the synthetic PIR typing system, atlantoaxial dislocation can be better classified according to its pathogenesis, imaging manifestation and mechanic stability. This system can also be served as a guide for clinical treatment. Anterior TARP operation and posterior atlantoaxial trans-pedicle screw-rod fixation are the main methods for the treatment of atlantoaxial dislocation.</p>

Preparation of cisplatin-impregnated coral hydroxyapatite drug delivery system / 南方医科大学学报

<p><b>OBJECTIVE</b>To prepare a cisplatin-impregnated coral-derived hydroxyapatite (CCHA) drug delivery system (DDS), and evaluate its inhibitory effect on human osteosarcoma cells U-2 OS, human breast cancer and prostatic carcinoma cells PC-3 in vitro.</p><p><b>METHODS</b>The coral-derived hydroxyapatite (CHA) was manufactured by hydrothermal exchange and impregnated with cisplatin by vacuum freeze-drying techniques. The leaching solutions of this DDS was collected at different intervals in a course of 8 weeks and their inhibitory effect on the cells was tested in vitro by MTT assay.</p><p><b>RESULTS</b>Electron microscope showed that cisplatin was distributed homogeneously in the pores of CHA. The inhibition rates of the leaching solution on all the tumor cells exceeded 50% except for PC-3 cells, whose inhibition rate was 29.92% when treated with the solution collected at the eighth week.</p><p><b>CONCLUSION</b>CCHA allows sustained drug release and maintains excellent inhibitory effect on human bone tumor cells within 8 weeks in vitro.</p>

Anatomic evaluation the entry point of C2 pedicle screw / 中华外科杂志

<p><b>OBJECTIVE</b>To study the relevant position of C(2) pedicle to C(2) inferior articular process, set up a technique of C(2) pedicle screw placement with the inferior articular process of axis as an anatomic landmark.</p><p><b>METHODS</b>Fifty C(2) bone specimens were used to measure the distance from the sagittal midline to the medial border, the midpoint and the lateral border of C(2) inferior articular process or C(2) pedicle; the width and the height of the C(2) pedicle were also evaluated. The anatomic relation between the measurements data of C(2) pedicle and that of C(2) inferior articular process were analyzed, and the technique of C(2) pedicle screw fixation was established.</p><p><b>RESULTS</b>The medial border of C(2) inferior articular process was averaged (3.67 +/- 0.41) mm lateral to that of C(2) pedicle, and the midpoint C(2) inferior articular process was averaged (1.15 +/- 0.44) mm lateral to the lateral border of C(2) pedicle, respectively. Using the C(2) inferior articular process as landmark, two techniques was established for C(2) pedicle screw placement. The entry point of method A was located in 2 mm medial and superior to the central point of C(2) inferior articular process; the entry point of method B was at the crossing point of the medial border C(2) inferior articular process with the superior quarter of C(2) inferior articular process.</p><p><b>CONCLUSIONS</b>There is a steady anatomic relation between C(2) pedicle and C(2) inferior articular process, the C(2) inferior articular process could be as a convenient key anatomic landmark to determine the location of C(2) pedicle and the position of C(2) pedicle screw entry point.</p>

The anatomical study of transoral atlantoaxial reduction plate internal fixation / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>To study relevant anatomical features of the structures involved in transoral atlanto-axial reduction plate (TARP) internal fixation through transoral approach for treating irreducible atlanto-axial dislocation and providing anatomical basis for the clinical application of TARP.</p><p><b>METHODS</b>Ten fresh craniocervical specimens were microsurgically dissected layer by layer through transoral approach. The stratification of the posterior pharyngeal wall, the course of the vertebral artery, anatomical relationships of the adjacent structures of the atlas and axis, and the closely relevant anatomical parameters for TARP internal fixation were measured.</p><p><b>RESULTS</b>The posterior pharyngeal wall consisted of two layers and two interspaces: the mucosa, prevertebral fascia, retropharyngeal space, and prevertebral space. The range from the anterior edge of the foramen magnum to C(3) could be exposed by this approach. The thickness of the posterior pharyngeal wall was (3.6+/-0.3) mm (ranging 2.9-4.3 mm) at the anterior tubercle of C1, (6.1+/-0.4) mm (ranging 5.2-7.1 mm) at the lateral mass of C(1) and (5.5+/-0.4) mm (ranging 4.3-6.5 mm) at the central part of C(2), respectively. The distance from the incisor tooth to the anterior tubercle of C(1), C(1) screw entry point, and C(2)screw entry point was (82.5+/-7.8) mm (ranging 71.4-96.2 mm), (90.1+/-3.8) mm (ranging 82.2-96.3 mm), and (89.0+/-4.1) mm (ranging 81.3-95.3 mm), respectively. The distance between the vertebral artery at the atlas and the midline was (25.2+/- 2.3) mm (ranging 20.4-29.7 mm) and that between the vertebral artery at the axis and the midline was (18.4+/- 2.6) mm (ranging 13.1-23.0 mm). The allowed width of the atlas and axis for exposure was (39.4+/-2.2) mm (ranging 36.2-42.7 mm) and (39.0+/-2.1) mm (ranging 35.8-42.3 mm), respectively. The distance (a) between the two atlas screw insertion points (center of anterior aspect of C(1) lateral mass) was (31.4+/-3.3) mm (ranging 25.4-36.6 mm). The vertical distance (b) between the line connecting the two C(1) screw entry points and that connecting the two C(2) screw entry points (at the central part of the vertebrae, namely 3-4 mm lateral to the midline of C(2) vertebrae) was (21.3+/-2.7) mm (ranging 19.4-24.3 mm), with an a/b ratio of 1.3-1.5. The screws of TARP had a lateral tilt of 12.2 degrees+/-0.4 degrees(ranging 10.2 degrees-14.6 degrees) at C(1) and a medial tilt of 7.3 degrees+/-0.3 degrees (ranging 5.1 degrees-9.4 degrees) at C(2) relative to the coronal plane.</p><p><b>CONCLUSIONS</b>An atlanto-axial surgery through transoral approach is safe and feasible. This approach is suitable for an anterior TARP internal fixation, and the design of the internal fixation system should be based on the above anatomical data.</p>

Transoral atlantoaxial reduction plate fixation for irreducible atlantoaxial dislocation / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>To design a clinically applicable transoralpharyngeal atlantoaxial reduction plate (TARP), introduce the operation procedure, and evaluate its preliminary clinical effects.</p><p><b>METHODS</b>A novel TARP system, including butterfly titanium alloy plate, self-locking screws, atlantoaxial reductor and other operational instruments was developed. This system was applied clinically on five patients with irreducible atlantoaxial dislocation of congenital or traumatic origin. During operation, the reduction was completed by the combined action of the plate and the atlantoaxial reductor after transoral joint release and cord decompression. Bone graft granules were implanted between the bilateral atlantoaxial joints and TARP was used to immobilize subsequently the atlas and axis.</p><p><b>RESULTS</b>Clinical application demonstrated that TARP could induce instant reduction and that the method was operationally feasible and its postoperational effect was satisfactory.</p><p><b>CONCLUSIONS</b>The design of TARP is novel. The operational procedure is simple and easy to use. Furthermore, instant reduction can be completed during the operation and the fixation is relatively stable. TARP is an ideal alternative for irreducible atlantoaxial dislocation and may have excellent prospects for further clinical applications.</p>

Anatomic identification of the location of the pedicle of atlas with the lateral mass of C2 to C4 as the landmark / 中华外科杂志

<p><b>OBJECTIVE</b>To study the relevant position of the pedicle of C1 to the lateral mass of C(2-4), set up an identification technique for the entry point decision of C1 pedicle screw by using the lateral mass of C(2-4) as anatomic landmarks.</p><p><b>METHODS</b>Twenty cadaver specimens were used to measure the distance from the sagittal midline of spine to the medial border, the midpoint and the lateral border of C1 pedicle or the lateral mass of C2, C3 or C4. The anatomic relation between the measurements data of C1 pedicle and that of the lateral masses of the cervical vertebrae were analyzed, and the technique of C1 pedicle screw fixation was established.</p><p><b>RESULTS</b>The average medial border of the lateral mass of C2, C3 and C4 was 0.37 mm, 0.27 mm and 0.24 mm lateral to that of C1 pedicle, the average midpoint of the lateral mass of C2, C3 and C4 was 1.18 mm, 1.41 mm and 1.74 mm lateral to that of C1 pedicle, and the average lateral border of the lateral mass of C2, C3 and C4 was 1.96 mm, 2.54 mm and 3.24 mm lateral to that of C1 pedicle, respectively.</p><p><b>CONCLUSION</b>There is a steady anatomic location relation between C1 pedicle and the lateral mass of C2, C3 or C4. As well as the lateral mass of C2, the lateral mass of C3 or that of C4 could be convenient anatomic landmarks to determine the location of C1 pedicle and the position of C1 pedicle screw entry point.</p>

Design and preliminary clinical application of transoralpharyngeal atlantoaxial reduction plate / 中华外科杂志

<p><b>OBJECTIVE</b>To design transoralpharyngeal atlantoaxial reduction plate (TARP), evaluate its biomechanical performance and observe its preliminary clinical effect.</p><p><b>METHODS</b>A brand-new TARP system was designed, including butterfly titanium alloy plate, self-locking screws, atlantoaxial reductor and other operation instruments. Twelve fresh occipital bone-C(3) specimen were designed for biomechanical test including range of motion (ROM) (n = 6) and screw pull-out strength (n = 12). Preliminary clinical application of TARP was reported.</p><p><b>RESULTS</b>The reduction mechanism of the TARP system was designed cleverly. TARP had equal effect with Magerl + Brooks and it was more stable than the other three clinically widely used atlantoaxial fixators: Magerl, Brooks and anterior transarticular screw fixation through C(2) vertebral body. TARP's C(1) and C(2) screws were strong enough for atlantoaxial arthrodesis and their antipull-out performance was excellent. Clinical application on irreducible atlantoaxial dislocation proved that TARP had the function of instant reduction, the operation was feasible and the operation effect was significant.</p><p><b>CONCLUSION</b>TARP's design is novel and it has excellent biomechanical performance. The operation procedure is simple and reasonable. Furthermore, instant reduction could be completed during the operation and the fixation is strong. Above all, TARP is creative and will have excellent prospect.</p>

Results of 1310 knees of meniscal treatment evaluated by arthroscopy / 中华外科杂志

<p><b>OBJECTIVE</b>To evaluate results of 1310 knees of meniscal treatments by arthroscopy and to present good method of meniscal treatment.</p><p><b>METHODS</b>Their age, traumatic mechanism and effects under arthroscopy were analysed in a series of 254 patients with meniscal injuries, there were 880 males and 374 females, the average of the patients was 25.5 years. The meniscal repair in 68 knee, partial meniscectomy in 756 knee, total meniscectomy in 480 knee and conservative treatment in 6 cases.</p><p><b>RESULTS</b>The patients were followed up 1 to 12 years with the average of 4 years and 3 months. The mean Lysholm score was 86.3 points in arthroscopic meniscal repair, 84.0 points in partial meniscectomy and 76.1 points in total meniscectomy. The mean Lysholm 98.7 points in all children patients with conservative treatment. They showed significant difference (P < 0.01) in the results of three treatments.</p><p><b>CONCLUSIONS</b>Meniscal injuries should not cut off as it, should be repaired in 5 mm from meniscus to synovium and or partial meniscectomy. The general adoption is not the surgical operation on meniscal injuries of the child.</p>

Surgical anatomy of transoral atlantoaxial reduction plate internal fixation / 中华外科杂志

<p><b>OBJECTIVE</b>To provide anatomical data for transoral atlantoaxial reduction plate internal fixation.</p><p><b>METHOD</b>Microsurgical dissecting was performed on 10 fresh craniocervical specimens layer by layer according to transoral approach. Stratification of posterior pharyngeal wall, course of vertebral artery, adjacent relationships of atlas and axis and correlative anatomical parameters of internal fixation to atlantoaxial joint were observed.</p><p><b>RESULT</b>(1) Posterior pharyngeal wall consisted of 2 layers and 2 interspace: mucosa, anterior fascia of vertebrae, posterior interspace of pharynx and anterior interspace of vertebrae. (2) The range from anterior rim of foramen magnum to C3 could be exposed by this approach. (3) The distance between the vertebral artery at atlas and midline was (25.2 +/- 2.3) mm and that between the vertebral artery at axis and midline was (18.4 +/- 2.6) mm. (4) The width of atlas and that of axis could be exposed respectively to (39.4 +/- 2.2) mm and (39.0 +/- 2.1) mm. The distance (a) between 2 atlas screw inserting points (center of anterior aspect of C-1 lateral mass) was (31.4 +/- 3.3) mm. The vertical distance (b) between the connecting line of 2 atlas screw inserting points and that of 2 axis screw inserting points (at the central part of the vertebrae which was 3 - 4 mm lateral to the midline of C-2 vertebrae) was (18.7 +/- 2.7) mm. The odds of a/b was 1.5 approximately 1.7.</p><p><b>CONCLUSIONS</b>Anterior atlantoaxial plate internal fixation through transoral approach is suitable and feasible. The design of the plate should be based on the above data.</p>

Percutaneous vertebroplasty in treatment of compression fracture of thoracic and lumbar vertebrae / 中华创伤杂志

Objective To discuss the value and experience of the percutaneous vertebroplasty (PVP)in the treatment of vertebral body compression fracture(VCF)in aged osteoperosis.Methods PVP was performed in 44 cases with VCF including 28 with single vertebral compressed fracture,12 with double compressed fracture and four with triple compressed fracture,with 67 vertebrae,for clinical and radiologieal evaluation.Results The mean follow-up was 15 months(4-23 months).There could be seen immediate relief of pain in 40 cases,out-of-bed activities at operation day in 19 and out-of-bed activ- ities at second day after operation in 25.Postoperative X-ray showed uniformly distributed bone cement in the vertebral,without leakage.Conclusion PVP is a recommendable method for VCF,for it has ad- vantages of pain relief,vertebrae stabilization,minimal invasion and minor complications.