Objective To investigate the influences on the femur cortex of the rabbit after ovariectomy and its mechanism.Methods Eighty 6 months-old female pure New Zealand rabbits were divided into two groups:40 rabbits in ovariectomy group and 40 in sham-operation group.The weight averaged 2.2±0.28 kg.Four weeks and 8 weeks after operation,a series of tests were performed in both groups concerning the number,the volume,the rate and the maximal load of cortical bone porosity.The number,the length and the density of linear crack in rabbit femur cortex were documented after repetitive application of minor trauma.Results Micro-CT demonstrated that both on week 4 and 8 after operation,the number,the volume and the rate of cortical bone porosity were all significantly higher in ovariectomy group than that of the control group.Four weeks after operation,the biomechanical test showed the significantly lower average maximal load of rabbit femur in ovariectomy group (1 892.60±59.09) than that of in control group (1 949.25±53.12) (P=0.003).Eight weeks after operation,the average load of both groups decreased to some extent,which was 1 944.55±41.76 in control group and 1 692.40±85.08 in ovariectomy group respectively (P=0.000).However,the average maximal load of ovariectomy group decreased more significantly.Having application of repetitive minor trauma to the bone,the number,the length and the density of linear crack of cortical bone were 3.40± 1.67,216.80± 17.60 μm and 0.40±0.08/mm2 in ovariectomy group,and 2.00± 1.17,160.45± 16.89 μm and 0.29±0.13/mm2 in control group 4 weeks later.And after 8 weeks,they were 5.15±1.18,334.60±13.94 μm and 0.35±0.10/mm2 in ovariectomy group,and 3.10±1.37,182.10±9.80 μm and 0.24±0.09/mm2 in control group.The number,the length and the density of linear crack of cortical bone were all significantly higher in ovariectomy group than that of in control group both on week 4 and on week 8 after operation.Conclusion Ovariectomy increases the porosity of cortical bone of rabbit,destroys its biological property,accelerates the fatigued damage and delays the healing process.These changes may be attributed to fracture and delayed union after fracture.

Objective To analyze the risk factors of incision infection and spinal canal hematoma after lumbar spinal posterior surgery.Methods Data of 33 patients with incision infection and 25 patients with spinal canal hematoma after posterior surgery for lumbar spinal disease from January 2010 to December 2014 were retrospectively analyzed.For the patients with incision infection,20 of them were males and 13 were females,with an average age of 58.85±8.76 years (range 38-79 years).Of these patients,5 were diagnosed with lumbar disc herniation,9 with lumbar spondylolisthesis,15 with lumbar spinal stenosis and 4 with lumbar vertebral fracture.For patients with spinal canal hematoma,17 of them were males and 8 were females,with a mean age of 60.96±11.37 (range,38-77).The diagnoses of them were lumbar disc herniation in 18 patients,spondylolisthesis in 3 patients and spinal stenosis in 4 patients.From the same period database,patients who underwent lumbar posterior lumbar surgery with no postoperative complications were selected by 3:1 ratio as the control group according to age,gender and diagnosis.Results For patients with incision infection,it was found that diabetes mellitus,preoperative RBC,hemoglobin,total protein,albumin,serum calcium,operation time,number of segment fusion,intraoperative blood loss,postoperative WBC,RBC,hemoglobin and platelet were significantly different from those with non-infection group.Moreover,multivariate logistic analysis showed that diabetes mellitus (OR=3.716,P=0.032),preoperative serum calcium (OR＜ 0.001,P=0.001),intraoperative blood loss (OR=1.002,P=0.014),postoperative hemoglobin (OR=0.923,P=0.018) and postoperative platelet (OR=1.007,P=0.017) were independent risk factors for postoperative incision infection.For patients with spinal canal hematoma,it was found that patients' preoperative total protein,albumin,serum calcium,platelet,operation time,intraoperative blood loss and postoperative total protein were significantly different from non-hematoma group.Multivariate logistic analysis showed that preoperative serum calcium (OR＜ 0.001,P=0.001),preoperative total protein (OR=1.298,P=0.043),intraoperative blood loss (OR=1.003,P=0.021) and postoperative total protein (OR=1.080,P=0.028) were independent risk factors for postoperative spinal canal hematoma.Conclusion The preoperative diabetes mellitus,serum calcium,intraoperative blood loss,postoperative hemoglobin and platelet were important risk factors for lumbar incision infection.And preoperative serum calcium,total protein,intraoperative blood loss and postoperative total protein were the risk factors for spinal canal hematoma.

Axial symptom,also called axial pain or axial neck pain,is a common complication after posterior cervical spine surgery.The symptom can be neck pain,as well as rigid,tension and dullness.The incidence of axial syndrome is estimated between 5.2％ and 61.5％.Often,the symptom does not disappear spontaneously.The quality of patients' life as well as the effectiveness of cervical laminoplasty is affected.It can be divided into early and late axial pain based on the onset time.The mechanism and reason are different,but both are difficult to subside.The incident of axial symptom is relatively high in conventional laminoplasty.However the modified one which preserve posterior ligament-muscular structure can reduce the incidence significantly.C2 spinal process as the attachment of cervical semispinalis,could reduce the incidence of kyphosis after operation.And C7 spinal process is an important structure in posterior ligament-muscular structure.Both should be preserved as much as possible in order to maintain intact attachment of muscles,which facilitates the patient to restore soft tissue tension by rehabilitation.Rigid fixation is another method of modification,it could avoid re-close of the open door,and reduce soft tissue injury.However,attention must be paid not to destroy facet joint to cause new axial symptom.Risk factors of axial symptom include past shoulder and neck pain and stiffness,others remain controversial.There is no correlation between loss of range of motion after surgery as well as change of cervical alignment and axial symptom.It is more likely to be a different result due to muscle atrophy.Although there are no golden standard of laminoplasty,doctors should follow these principles:preserve C2 and C7 spinal process when possible,rigid fixation to avoid reclose,reduce immobilization after operation,and encourage patient to start rehabilitation as early as possible to reduce incident of axial symptom.

Rupture of anterior cruciate ligament (ACL) is a common sports injury.It will cause knee osteoarthritis because of joint instability and acceleration of degenerative changes after injury.Arthroscopic reconstruction with a tendon graft is a common procedure to achieve function recovery.A series of histological changes and structural modification happened between the tendon and bone tunnel after ACL reconstruction and complete tendon-bone healing was achieved finally.A number of factors affects the healing process which determined the long-term result of the treatment.Published literatures reported that about 11％-32％ patients underwent ACL reconstruction were not satisfied with the results and 10％ of them required reoperation.Studies on the tendon-bone healing have long been a research hotspot in sports medicine.Controversy still remains not only on the fundamental healing process but also on the stimulating factors despite of a large amount of researches on its physiological basis,influencing factors,et al.This article provides a review of the basis and influence factors of the healing process,and summarizes the methods to accelerate the process of tendon-bone healing.

Objective To investigate the clinical features,safety and clinical efficacy of the posterior decompression and interbody fusion with internal fixation for complete thoracolumbar fracture and dislocation.Methods The clinical data of 23 patients with complete thoracolumbar fracture and dislocation treated by posterior decompression and interbody fusion with pedicle screw fixation from August 2011 to October 2014 were retrospectively analyzed.There were 18 males and 15 females,aging from 20 to 50 years old with an average age of 38.2±0.3 years.There were 8 cases of T10,11 vertebral dislocation,8 of T11,12 vertebral dislocation,3 of T12L1 vertebral dislocation,and 4 of L1.2 vertebral dislocation.All the patients had different degrees of multiple rib fractures and pneumothorax complications.Preoperative spinal cord nerve function was evaluated according to the American Spinal Injury Association of spinal cord function (ASIA).There were 10 cases of ASIA grade A and 13 cases of grade B.Operation time,intraoperative blood loss,clinical outcome,imaging X-ray and CT examination,segmental kyphosis angle and bone graft fusion were recorded.Results All the patients were followed up for 13 to 26 months,average 20.2±4.3 months.The operation time ranged from 150 to 260 min with the average time of 180.3± 14.8 min;intraoperative blood loss was 800-1 500 ml with the average of 950.2±98.1 ml.Preoperative sagittal Cobb angle was-13.5° ±6.3° (range,-20.1° to 2.3°);postoperative sagittal Cobb angle was 1.43°±6.4° (range,-7.6° to 3.5°);at the latest follow-up,sagittal Cobb angle was 1.6°±6.3° (range,-8.1° to 10.3°);the dislocation reduced from preoperative 100％ to postoperative 0-15％ (10％±6％).After operation,the ASIA grade of 2 cases improved from A to B,and 5 cases improved from B to C.All of the patients had bone fusion after operation,no false joint or nonunion occurred,no loosening or breakage of internal fixation occurred.Conclusion There are high risks and difficulty of surgery for those who with thoracolumbar fracture dislocation and severe injuries of spine and spinal cord combined with multiple injuries.Proper treatment of preoperative complications is the premise of good curative effect;reliable fusion and long segment internal fixation is the key of operation.Single posterior decompression and reduction with interbody fusion and internal fixation is less invasive and could achieve satisfactory clinical efficacy.

Objective To study the techniques and outcomes of using a retrograde pedicled vascularized radius bone flap based on the 1st,2nd intercompartmental supraretinacular artery (1,2ICSRA) for scaphoid nonunion through dorsal and palmar approaches.Methods Between March 2013 and April 2015,16 patients with scaphoid nonunion were treated by surgery through palmar and dorsal approaches.There were 14 males and 2 females with an average age of 29.1 years (range,19-51 years).The location of lesion was 6 cases on the left and 10 cases on the right.5 cases were treated with plaster fixation.11 cases weren't treated after wrists injured.The preoperative time was 6-26 months,with an average of 16.5 months.The operation was completed within one incision.The bone flaps based on 1,2ICSRA were taken through dorsal approach.The broken ends of the scaphoid fracture were cleaned,and the deformity was corrected with bone grafting and internal fixation through palmar approach.Time of fracture union and wrist pain resolution was evaluated.Wrist motion and grip strength were measured and compared.The result of the latest follow-up was used as the criterion for efficacy evaluation.The wrist pain was evaluated using visual analogue scale (VAS) and the postoperative wrist function based on the modified Mayo wrist score was recorded.Results Post-operative follow up ranged from 6-19 months,with an average of 11 months.Bone union was achieved in all the cases,so the healing rate was 100％.7 cases were healed in 11 weeks.5 cases were healed in 13 weeks.3 cases were healed in 15 weeks.1 case was healed in 17 weeks.The average healing time was 12.5 weeks.The humpback deformity of Scaphoid and DISI of 7 cases were corrected.The bending of wrist could reach 60.2°±3.2°,and the elongation could reach 51.3°± 3.5°.The radial deviation of wrist could reach 13.6°±1.42°,and ulnar deviation could reach 24.4°±1.8°.The range of grip strength was 29-64 kg,with an average of 45 kg.The 16 patients returned to normal work.The pain after wrist movement of 14 cases was completely disappeared,and the VAS was 0.Two cases felt slight pain when wrist was overworked,and the VAS were 0.9 and 1.2.The wrist joint function of patients recovered well.The modified Mayo score was 69-99,with an average of 90.75.The functional results were 12 excellent,2 good,and 2 fair,and the excellent and good rate was 87.5％ (14/16).No complications such as infection,failure of screws,orthopaedic arthritis or scaphoid necrosis were found during the follow-up period.Conclusion The technique of 1,2 ICSRA pedicled bone graft and palmar bone grafting for nonunion of scaphoid can provide convenience for us to deal with the broken ends of the scaphoid fracture,correct the malformation and graft bone through dorsal and palmar approaches.This method can protect the blood supply of the scaphoid,and promote scaphoid union.

Objective To investigate the clinical results of Bi-plane robot navigation for cannulated screw fixation in the treatment of femoral neck fractures.Methods Between May 2011 and May 2015,86 patients with femoral neck fracture who were fixed with cannulated screws were retrospectively analyzed.The patients were divided into navigation group and non-navigation group according to whether the Bi-planar robot used for navigation or not.The patients were matched concerning gender,age and Garden classification.A total of 64 patients were included in the study.In navigation group,there were 32 cases,including 10 males and 22 females.The average age was 59.4±5.6 yr (range,51-68 yr).According to Garden classification,there were 1 case of type Ⅰ,7 cases of type Ⅱ,14 cases of type Ⅲ and 10 cases of type Ⅳ.In non-navigation group,there were 32 cases,including 12 males and 20 females.The average age was 59.1±4.9 yr (range,53-70 yr).According to Garden classification,there were 1 case of type Ⅰ,5 cases of type Ⅱ,18 cases of type Ⅲ and 8 cases of type Ⅳ.Sixty-four cases were all fixed with cannulated screws.The fluoroscopy time,fluoroscopy times,drilling times,times of cannulated screw replacement,cannulated screw insertion time,blood loss,relative position between any two cannulated screws in postoperative AP view and lateral view,the angle between each cannulated screw and the femoral neck axis,fracture healing time and functional score were recorded.Results The parameters in navigation group versus non-navigation group were as follows:the average fluoroscopy time was 10.1±2.9 s vs 36.8±7.5 s,the average fluoroscopy times was 11.4±3.2 vs 43.9±11.0,the average drilling times was 3.9±1.1 vs 18.5±3.2,the average times of cannulated screw replacement was 0.4±0.6 vs 1.0±0.7;the average blood loss was 29.4± 14.7 ml vs 50.2± 17.1 ml,cannulated screws placement time averaged 28.8±7.3 min vs 43.8±7.9 min.The angle between any of two cannulated screws averaged 3.1°±1.1° vs 7.3°± 1.2° in AP view and 2.9°±1.0° vs 4.4°±2.3° in lateral view,the angle between the cannulated screw and the femoral neck axis averaged 4.4°±1.6° vs 7.5°±1.7° in AP view and 4.9°±1.6° vs 8.0°±1.3° in lateral view.Significant differences were found concerning all above parameters between the two groups.Conclusion Bi-plane robot navigation technique helps more accurate cannulated screw fixation in the treatment of femoral neck fracture.This technique is less invasive.It decreases the time of screw insertion and reduces the radiation exposure.

Objective To investigate the mid-term outcome of high tibia osteotomy (HTO) combined with tibial tuberosity limited rotation in the treatment of disorder of patellofemoral joint with knee varus.Methods HTO was performed in all 42 patients.The lower limb alignment,lateral femoral tibial angle,medial proximal tibial angle,Q angle and TF-TG were measured before and after operation.All the patients with disorder of patellofemoral joint were divided into three types based on preoperative patellar trajectory and TF-TG.According to different types we chose the limided rotation of distal tibia through adjustment of tibial tubercle location to improve patellar track.Type Ⅰ in 10 cases and type Ⅱ in 12 cases only accepted HTO,type Ⅲ in 20 cases accepted HTO and tibial tubercle rotation.The rotation angle was determined according to preoperative imaging results and foot forward angle.Before and after operation patellar tilt angle,patellofemoral angle and lateral patellar angle were measured.Results 42 patients were followed up for more than 5 years,an average of 72.20± 12.60 months (60-88 months).No nerve damage,infection and bone nonunion occurred.The patellar tilt angle was improved from 12.45°±3.76° to 6.98°± 1.78° 5 years after operation.The patellofemoral angle was improved from 12.51°±4.71° to-4.70°±2.57° 5 years after operation,and the lateral patellar angle was improved from 1.50°±4.90° to 7.80°±3.10°.Preoperative lateral femoral tibial angle was improved from 182.45°±2.20° to postoperative 174.60° ±3.50°,medial proximal tibial angle was improved from preoperative 78.75°± 3.50° to postoperative 93.25°±1.95°.The Lysholm score was improved from preoperative 53.10±5.60 to 92.70±5.50.The preoperative IKDC subjective score was improved from 47.50±6.40 to 91.30±6.90.The Kujala score was 62.40±8.70 before operation and 87.30±4.10 5 years after operation.Visual analogue score (VAS) was 7.50±2.45 before operation and 1.50±0.90 5 years after operation.The short and mid-term follow-up,knee patellar trajectory and lower limb alignment was good,postoperative symptoms was satisfactory and acceptable.Conclusion HTO combined with limited rotation of the tibial tubercle could improve patellar trajectory and lower limb alignment to relieve pain,and has satisfactory mid-term outcome in the disorder of patellofemoral joint with knee yarus patients.

Objective To evaluate the clinical effects of the Masquelet technique combined with antibiotic calcium sulfate pellets in treating infected bone defects.Methods From February 2014 to February 2016,9 patients with infected bone defects were treated in our department,including 7 males and 2 females,with an average age of 37.0 years (range,24-56 years).6 cases were infected because of open fractures,3 infected after internal fixation operation.All defects were located in the lower limb diaphysis and metaphysis (3 cases in femur,6 cases in tibia).The length of the bone defects were 4-12 cm after debridement,all defects filled with PMMA loaded with Vancomycin,and fixed with exterual fixators.After 6-10 weeks,the bone cement spacers were taken out and the antibiotic calcium sulfate pellets were implanted into the membrane.A certain amount of autogenous cancellous bone granules would be mixed into the calcium sulfate pellets if the defect was larger than 6-8 cm.5 cases remained fixed with external fixators,3 cases replaced for plates,1 case replaced for plaster external fixator.Regular X-ray follow-ups were taken and complications recorded as well.Evaluate the healing of bone defect and functional recovery of adjacent joints by Samantha X score system,visual analogue scale (VAS) and Paley method,respectively.Results The 9 cases were followed up for a mean duration of 9.3 months (range,6-15 months).All bone defects healed after a mean time of 14 weeks (range,10-24 weeks).The wound poor healing occurred in only 1 case in the first stage of surgery,and cured by dressing changes.No complications of the recurrence of infection and implant failure.At the last follow-up,the average Samantha X score was 4.9,the VAS score was 0 to 3 (average 1.5) for patients standing on crutches and all the bone defect healing graded excellent evaluated by Paley method,the functional recovery of the adjacent joints graded:excellent in 6 cases,good in 2 cases,and fair in 1 case (the excellent and good rate was 89％).Conclusion Masquelet technique combined with antibiotic calcium sulfate particles is effective in the treatment of infected bone defects.

Objective To monitor the autophagy in osteosarcoma cells by constructing three rLC3B fusion expression vectors,respectively.Methods Rat LC3B gene sequence was amplified by PCR and cloned into pEGFP-C 1 and pmCherry-C1 to construct the fusion expression vector of pEGFP-rLC3B and pmCherry-rLC3B.Subsequently,the EGFP-rLC3B sequence was obtained by PCR with the pEGFP-rLC3B as a template,and cloned into pmCherry-C 1,so the pmCherry-EGFP-rLC3B fusion expression vector was constructed.Three plasmids were transfected into U-2OS cells,and the starvation or Rapamycin was adopted to induce autophagy or the chloroquine or Baf-A1 was used to inhibit autophagy,to verify the above plasmids' function in autophagy detection by laser scanning confocal microscopy.Western blot was used to detect the endogenous LC3B and exogenous EGFPrLC3B,pmCherry-rLC3B and mCherry-EGFP-rLC3B,and to verify the correct expression of exogenous rLC3B and their function of autophagy detection.Finally,cleaved free EGFP was detected by western blot to evaluate the level of autophagic degradation.Results Three fusion expression vectors were constructed successfully through sequencing and restriction enzyme digestion validation.The starvation or Rapamycin was adopted to induce autophagy or the chloroquine or Baf-A 1 was used to inhibit autophagy in transfected U-2OS cells.Clear autophagosomes and autolysosomes were observed by laser scanning confocal microscopy.Endogenous LC3B and exogenous EGFP-rLC3B,pmCherry-rLC3B and mCherry-EGFP-rLC3B were detected through western blot.Finally,western blot verified that the expression of cleaved free EGFP was significantly up-regulated with the increase of starvation time.12 h group increased 1.05 times than the control group and 24 h group increased 1.56 times,showing that the levels of autophagic degradation increased.Conclusion EGFP-rLC3B can be used to detect autophagosome and evaluate the level of autophagic degradation.mCherry-rLC3B can be used to detect autophagosome and autolysosome,but can't distinguish autophagosome from autolysosome.The pmCherry-EGFP-rLC3B has an advantage in the detection of autophagic flux which can distinguish autophagosome from autolysosome.