Objective\ To observe the practicality of sonography for differentiating the compression factors and judging whether thorough decompression anterior to the dura sac has been obtained. Methods Posterior midline incision was used in a total of 16 cases. After the laminae were resected, normal saline was poured into the operation field, and ultrasound examination performed with a 5.0 MHz sectorscanner. Combined with preoperative imaging (CT or MRI),the compression factors were differentiated. The isolated tissue(bone or disc)pieces in spinal canal were removed first,then reduction of approximate and distal parts of the injuried spinal column was obtained with the help of the Dick devices. Posteriorly protruded bone mass was tumbled in carefully supervised with sonography. The sonographic criterion for thorough decompression consisted of the reappearance of the anterior subarachnoid and an even and smooth echo of posterior dura mater. Results\ The sonographic criterion for thorough decompression was achieved in all cases. No bone mass posterior displacement was observed on postoperative rontgenogram or CT examination. Partial or complete recovery of neural function was obtained in 13 cases. Conclusion\ All elements contributing to anterior dura sac compression can be readily recognized by sonography,which offers a reliable criterion for complete decompression.

Objective To study the variability of the parameters of the pedicle screw path and influencing factors of clinical significance. Methods A Picker PQ6000 Spiral CT was used to scan 736 vertebrae from C 3 to L 5 of 118 men and 80 women aged between 17 and 58. The largest transverse diameter, screw path length and e angle (the angle between the axis of the pedicle and sagittal plane) of each pedicle were measured. The contour of the vertebrae and the relationship of the sagittal axis of the spinal process, vertebral body and human body were inspected. Any discrepancy of these axes was measured and recorded. The gender, age, height and weight were recorded at the same time. Results Measurement of the biggest transverse diameter, screw path length and e angle at each vertebral level showed a wide range of value and quantity. Although the screw path length and the transverse diameter of the pedicle showed significant difference between man and woman, further covariance analysis for between subject effects revealed that no inter gender difference existed after the effects of height and weight were removed. Both height and weight showed significant positive correlation with the screw path length and transverse diameter of the pedicle, but no correlation with the e angle. Observation on the deformity of the vertebrae showed that the sagittal axes of the vertebral body and human body was discrepant in 14 thoracic and lumbar vertebrae; the sagittal axes of the spinal process and vertebrae was discrepant in 11 vertebrae; the transverse diameter of the pedicle was smaller than 4 mm in 14 vertebrae below T 9; 4 vertebrae showed lateral convex pedicle. Conclusion The parameters of the pedicle screw path varied in different subjects and different vertebral level with a large variability. The weight and height are two important factors to influence the parameters. Deformity is another factor which may lead to mistake of placement of the pedicle screw. To improve the accuracy of the pedicle screw, individual identification of the entering point and orientation should be considered and in some circumstances even special screws, should be used.

[Objective]To investigate feasibility and efficacy of clinical application of endoscopic anterior cervical decompression and fusion.[Method]With Metrx MED system and modified working tube and decompression instruments,endoscopic anterior cervical decompression and fusion were performed on 15 patients with cervical spondylotic myelopathy.A paramidline right transverse incision of 2 cm long was made.A channel between the neurovascular and visceral sheath was created through finger dissection.The dilators were inserted sequentially.An original one arm working tube or a modified,shortened working tube with double arms was inserted over the dilators.Then decompression and fusion with autologus graft was performed under endoscope.[Result]Once the tubular retractor was stably fixed throughout the operation,releasing of the discomfort was observed.All the compression tissue such as soft disc tissue or hard osteophyte and anterior longitudinal ligament or dura sac were clearly visualized under the endoscope.Shortened working tube provided improved visual field and increased manipulation space for the decompression instrument.The double arms enhanced stability of the working tube but could not eliminate moving of it during operation.Intraoperative blood loss was 200 ml to 800 ml.The operation lasted 80 to 210 minutes.The incision healed in one week.Postoperative discomfort in laryngeal region was light.All of the cases showed thorough decompression on postoperative MRI films and gained better spinal cord function at postoperative follow-up.No surgery-related complication were encountered.[Conclusion]Endoscopic anterior cervical decompression and fusion based on the use of a working tube is technically feasible.Compared with conventional method,this technique has the advantages of improved intraoperative visualization,thorough decompression,minimal trauma,quicker recovery and improved cosmetic result.Disadvantages waiting for further improving include:limited manipulation space,discomfort and potential hazards to the surrounding structure resulted from moving of the working tube.

[Objective]To study the prophylactic effects of high dose methylprednisolone(MP) for perioperative surgical treatment of thoracic spinal stenosis.[Method]From July 2003 to December 2007,a retrospective study of 40 patients who underwent simply posterior thoracic vertebral canal decompression was made.The patients were divided into 2 groups according to the application of MP or none-MP at perioperation.Twenty-one patients in MP group were treated with MP stoss(30 mg/kg,iv 15 min) 30 min prior to the decompression and then 45 min later MP(5.4 mg/kg/h) was continuted for 23 hours.Nineteen patients in the control group were treated with dexamethasone(DX) 15 mg 30 min prior to the decompression and then DX(10 mg/d,iv) was given for 3 days after operation.Neurological function improvement rates were evaluated according to the JOA scores(postoperative JOA scores-preoperative JOA scores /17﹣preoperative JOA scores)?100% at 3d,7d,3d and 12 months after operation.Complication were observed.[Result]Neurological function recovery rates were 33.54?10.01% in MP group and 28.29?8.73% in the control group at 3 days after operation.The difference was found to be significant(P0.05).Neurological deficit was found in 5 in control group,while no one in the MP group.[Conclusion]High dose of MP used perioperatively for thoracic stenosis can protect spinal cord and improve operative security,while it does not increase serious adverse complications.

BACKGROUND:Reducing blood loss could help to prevent the complications of total knee arthroplasty, relieve the swelling and discomfort postoperatively and accelerate the rehabilitation. OBJECTIVE:To explore the methods for reducing blood loss during total knee arthroplasty. METHODS:Totally 63 patients undergoing primary unilateral total knee arthroplasty were divided into two groups. Group 1 included 27 patients who received the conventional surgical techniques using tourniquet during the whole procedure with wound drainage, as control group. Group 2 included 36 patients who received the modified procedure only using tourniquet during prosthesis implantation without wound drainage, as experimental group. In the experimental group, we stitched the capsule closely. The preoperative and postoperative hemoglobin, decrease of hemoglobin, knee pain score, range of motion blood transfusion rate and wound healing were compared between the two groups. RESULTS AND CONCLUSION:(1) There was no significant difference in preoperative hemoglobin between the two groups. At 1, 4 and 7 days postoperatively, the hemoglobins were significantly lower in the control group than in the experimental group, and the decreases of hemoglobins were significantly lower in the control group than in the experimental group. (2) Knee pain score was not significantly different between the two groups. (3) The range of motion of the knee was significantly larger in the experimental group than in the control group at 7 days. (4) Blood transfusion rate was 18.5%in the control group, and wound healing was poor in one patient. There was no transfused case and wound problem in the experimental group. All wounds were healed normally. (5) There was no infection or hematoma in two groups. (6) With the modified procedure, we could reduce blood loss during total knee arthroplasty without blood transfusion after surgery, which was helpful to postoperative rehabilitation.

BACKGROUND:L-type calcium channels, as a kind of voltage-dependent calcium channel, is the main way of extracellular calcium ions into the cell, and play an important role in maintaining cellmorphology and physiological activities, characterized by a large single-channel conductance, slow channel attenuation, and longer duration of channel opening. Previous studies showed that basic fibroblast growth factor can promote the proliferation of chondrocytes cultured in vitro.
OBJECTIVE:To explore the effect of the L-type calcium channels on regulating chondrocyte proliferation and differentiation in response to basic fibroblast growth factor with patch-clamp.
METHODS:The chondrocytes were harvested from the joints of 3-day-old New Zealand rabbits. The second passage of chondrocytes was divided into experimental group and control group. Chondrocytes were incubated in media containing 10μg/L basic fibroblast growth factor and media alone separately. The opening of L-type calcium channels under the action of basic fibroblast growth factor was detected by patch-clamp. The intracellular calcium concentration was detected with laser confocal microscopy in the chondrocytes after 2 weeks of culture with basic fibroblast growth factor. Chondrocyte proliferation was analyzed by cellTiter kit after 8 days of culture. Type Ⅱ col agen was assessed quantitatively by immunohistochemistrical staining after 10 days of culture.
RESULTS AND CONCLUSION:Basic fibroblast growth factor has an inhibitory effect on the opening of the L-type calcium channels, resulting in a decrease in intracellular free calcium concentration (P<0.01). cellnumber was higher after culture with basic fibroblast growth factor than that cultured under conventional condition (P<0.01), and staining area of type II col agen significantly increased (P<0.05). Results verified that basic fibroblast growth factor can maintain intracellular Ca2+concentration at a low level by inhibiting the opening of L-type calcium channels, which can promote the proliferation and differentiation of chondrocytes.

BACKGROUND:Differences of knee anthropometry between individuals are significant, while preoperative templating is not accurate in predicting the prosthesis size.
OBJECTIVE:To improve the accuracy of pre-operative plan in predicting the prosthesis size in total knee arthroplasty using digital technologies.
METHODBetween January 2013 and May 2004, 50 patients (20 men and 30 women;aged 54-82 years;mean age, 67.8 years) received primary total knee arthroplasty for osteoarthritis and were retrospectively analyzed. According to the treatment, the patients were divided into two groups. The digital group, a series of 21 patients, underwent 64-row MDCT before total knee replacement. CT images were imported into Mimics, and three-dimensional models of femur and tibia were reconstructed. Then, computer-aided design files of different sizes of prostheses provided by the manufacturers were imported into Mimics, too. Surgical simulation of osteotomy and prostheses implantation were performed in Mimics, component size was determined by the contour of distal femur and proximal tibia. The control group, a series of 29 patients, underwent primary total knee arthroplasty using conventional approaches. The agreement between preoperative plan and the actual prosthesis size was assessed during the surgery. Postoperative X-ray of low limb was taken to evaluate the accuracy of sizing and the efficacy of digital technologies was assessed.
RESULTS AND CONCLUSION:The intraoperative and postoperative evaluation showed inaccurate sizing of femoral and tibial components in 1 case in digital group and in 11 cases in conventional group. The accuracy of prediction was 95%in digital group and 62%in conventional group, with significant differences between the two groups (P<0.05). Four overhanging and two notching cases were observed in conventional group, but none in digital group. The digital technologies provide an effective means for accurate prediction of prosthesis size and personalized surgical simulation.

Objective To evaluate the efficacy of bone marrow fenestration technique used for ro-tator cuff repair at the foot-print zone of rotator cuff under arthroscopy. Methods A total of 30 patients with full-thickness rotator cuff tear ( from 3 cm to 5 cm) were enrolled for this retrospective study who had been treated at Department of Orthopaedics, The People's Hospital of North Jiangsu from January 2015 to December 2016. Of them, 15 were treated under arthroscopy with simple suture bridge technique ( SB group ) and the other 15 under arthroscopy with bone marrow fenestration and suture bridge techniques ( BMSB group ) . The 2 groups were compared in terms of visual analogue scale ( VAS ) , American Shoulder and Elbow Surgeons ( ASES ) scale, Constant scores,range of motion of the affected shoulder and rate of retear after surgery. Results All the patients received follow-up for 11 to 14 months. Significant improvements were achieved in both groups in VAS scores at 3 months ( 1.9 ± 0.6 and 0.9 ± 0.6 ) , ASES scores ( 90.7 ± 3.6 and 92.3 ± 4.2 ) and Constant scores ( 88.9 ± 2.5 and 87.4 ± 3.4 ) at the last follow-up, compared with the preoperative values ( 4.7 ± 1.1 and 4.3 ± 1.5, 58.2 ± 7.2 and 55.6 ± 4.4, and 57.3 ± 6.7 and 55.9 ± 10.3, respectively) ( P ＜0.05), but there were no significant differences between the 2 groups in ASES scores, Constant scores or range of motion of the affected shoulder at the last follow-up ( P＞ 0.05). The VAS scores at 3 months for the BMSB group (0.9 ± 0.6) were significantly lower than that for the SB group (1.9 ± 0.6) ( P ＜0.05). There was no significant difference either between the 2 groups in the retear rate [ 20.0% ( 3/15 ) for SB group versus 26.7% ( 4/15 ) for BMSB group ] ( P ＞ 0.05 ) . Conclusion Application of bone marrow fenestration technique in addition to suture bridge technique can obviously relieve pain after rotator cuff repair, though it shows no advantage in functional recovery of the shoulder joint.