Objective To investigate the preliminary results and complications of a tapered proximal femur modular stem in total hip arthroplasty (THA).Methods From October 2010 to December 2011,tapered proximal femur modular stems were used for THA in 50 patients (56 hips).There were 14males and 36 females,at a mean age of 61 years (range,25-82 years).Forty-four patients had unilateral THA and six bilateral THA.Hip osteoarthritis secondary to developmental dysplasia of the hip occurred in 15 patients,femoral neck fractures in 12,avascular necrosis of the femoral head in 10,primary hip osteoarthritis in nine,rheumatoid hip arthritis in two,malunion of femoral neck fracture in one,and femoral head fracture combined with posterior dislocation of the hip in one.The adopted femoral component was a tapered proximal femur modular stem.Femoral head-acetabulum interface composed metal-polyethylene in 34 hips,ceramics-polyethylene in 12 hips,and ceramics-ceramics in 10 hips.There were 48 hips with standard femoral head (28 mm) and eight hips with non-standard femoral head (＞28 mm).Results Mean period of follow-up was 11 months (range,6-19 months) and two patients (two hips) were lost to follow-up.Harris hip score improved from 36 points (range,4-71 points) preoperatively to 89 points (range,55-98 points) at the final follow-up.There was one patient with mild pain in the thigh,one moderate pain,but none severe or critically severe pain at the final follow-up.At the final follow-up,no migration or loosening of the implanted prostheses occurred; periprosthetic bone ingrowth fixation on the femoral side was achieved in 53 hips and fibrous stable fixation in one hip ; apart from one hip of ＜ 2 mm prosthetic subsidence,the remained revealed no subsidence of the prostheses.Intraoperative complications included acetabulum perforation in one hip and periprosthetic femoral fracture in one hip.Conclusion The short-term results are satisfactory,but the potential risk of fretting/corrosion and even breakage at the modular stem junction remains.

Objective To compare the value of "linear shadow" of posterior vertebral body wall under standard lateral X-ray fluoroscopy and CT scan in evaluating the reduction of bone fragment retro-pulsed into the spinal canal so as to provide evidence for indirect reduction degree of bone fragment under X-ray fluoroscopy during operation. Methods A retrospective study was done on 25 cases of thoraco-lumbar burst fractures treated at our department. There were 15 males and 10 females, at age range of 24-66 yeas(average 44. 9 years). Preoperative CT scan confirmed burst fractures in all cases. Bone frag-ment occupied mearl 35. 2% of midsngittal diameter of injured segment. All cases were treated by indirect reduction with short-sesment pedicle instrumentation, rather than laminotomy or partial laminectomies. When imging of posterior vertebral body wall manifested a continuous and smooth"linear shadow" under standard lateral X-ray fluoroscopy during operation, bone fragment War considered to be under reduction. CT span was performed to evaluate the reduction of bone fragment postoperatively. Results The bone fragment occupation of midsngittal diameter of injured segment was decreased from preoperative 35. 2%to postoperative 8. 6%, with statistical difference(t=9. 122, P<0. 01). Neurological function of all 25 cases was normal at last follow-up. The decompression of spinal canal was effective. Conclusions A continuous and smooth"linear shadow"on posterior vertebral body wall imaging is a simple and effective way to judge the reduction of bone fragment retropulsed into the spinal canal and can provide evidence for whether laminotomies and pushing bone fragment are necessary during operation.

BACKGROUND:There is a general consensus that patients undergoing joint arthroplasty surgery wil be in hypercoagulable state and easily to induce deep vein thrombosis. Thromboelastography is a new kind of method to monitor blood coagulation state, but not widely used in orthopaedics. No final conclusion has yet been reached on whether we can guide the clinical prevention of deep vein thrombosis and medication through using thromboelastography to monitor perioperative coagulation state of patients treated with joint arthroplasty. OBJECTIVE:To investigate the correlation between thromboelastography and routine coagulation functional tests, and evaluate the clinical application value of thromboelastography in monitoring the perioperative coagulation state of patients treated with joint arthroplasty.
METHODS:A total of 204 patients who treated with joint arthroplasty at First Affiliated Hospital of Soochow University from November 2014 to August 2015 were retrospectively analyzed. The thromboelastography, routine coagulation, platelet and other data before and after the replacement were respectively col ected. The correlative analysis was conducted between the thromboelastography result and the results of conventional coagulation test, that is, routine coagulation and platelet count. RESULTS AND CONCLUSION:In total knee arthroplasty group, activated partial thromboplastin time and reaction time showed good consistency (φ=0.713, Kappa value=0.647);Prothrombin time had moderate correlation and general consistency with reaction time (φ=0.392, Kappa value=0.362);Coagulation time and fibrinogen had moderate correlation and consistency (φ=0.392, Kappa value=0.488);Aggregates formation rate (αangle) and fibrinogen had moderate correlation and consistency;the remaining parameters had poor correlation and consistency. In total hip arthroplasty group, there was a weak correlation and consistency between the reaction time, activated partial thromboplastin time and prothrombin time;the other correlations were poor. However, there was a higher proportion of consistent clotting trend between some parameters of thrombelastography and routine coagulation. In total hip arthroplasty group, the consistent proportion of coagulation time and fibrinogen accounted for 67.6%;the consistent proportion of aggregates formation rate (αangle) and fibrinogen accounted for 78.3%. These results suggest that thromboelastography and routine coagulation tests have some correlations and consistency. Thromboelastography parameters have more consistent tendency on the data. Thrombelastography can serve as an auxiliary mean to monitor coagulation state of perioperative joint arthroplasty.