Objective To evaluate biomechanical strength of locking compression plate (LCP) for fixation of periprosthetic proximal femur fractures (PPFF). Methods Eight matched pairs of Vancouver type B1 adult cadaveric PPFF specimens were fixed with the LCP and the inverted distal femoral less invasive stabilization system (LISS), respectively. Four bicortical locking screws (LCP group) and four unicortical locking screws were used to the length of prosthesis stem, and four double cortical locking screws were used to fix the distal end of the fracture in two groups, the distance from the locking screws to the fracture were also equal. The maximum bending load, maximum bending displacement, bending stiffness, maximum torque, maximum torsional angle and torsional stiffness of two groups in four-point bending test and torsion test were compared and analyzed. Results The maximum bending load, maximum bending displacement and bending stiffness of LCP group were all larger than those of LISS group, but the difference was not statistically significant (P>0.05). The maximum torque, maximum torsional angle and torsional stiffness of LCP group were obviously larger than those of LISS group，and there was a statistical difference between two groups (P<0.05). Conclusions The stiffness of anti-torsion with LCP is significantly better than that with LISS. Consequently, LCP has better biomechanical stability for PPFF.

Objective:To investigate the effect of enhancing the strength of the hamstring on the stability of the knee joint.Methods:Thirty patients with anterior cruciate ligament (ACL) tears were randomly divided into a training group ( n=15) and a control group ( n=15). After the injury′s edema stage, all of the subjects received the standard 6-stage rehabilitation training for ACL injury, including isokinetic exercise, isometric tension and contraction exercise, single or bipedal jumping, proprioception exercises and cardiovascular exercise. On the basis of that standard training, additional hamstring strengthening training was given to the training group. It involved three sessions of weight-bearing flexion of the knee joint six to eight times, at least five times a week for three months. All of the subjects underwent the passive relaxation test (PRT), knee function scoring (Lysholm scores) and weight-bearing MRI before and within 1 month after the training. Anterior shift of the tibia (TAS) was measured using weight-bearing magnetic resonance imaging (MRI). Results:Before the training there were no significant differences between the groups in terms of average PRT or Lysholm scores. After the training, the average PRT score in neither group had improved significantly. The average Lysholm scores of the training and control groups were not significantly different either, though both groups′ averages had improved significantly compared with before the training. The average tibial shifts were also significantly smaller than before the training, with the training group′s average significantly smaller than that of the control group.Conclusion:Increasing hamstring muscle strength can reduce tibial anteversion in the weight-bearing upright position and improve the stability of the knee joint after ACL injury.

Objective: To compare the clinical effects of surgery within and over 48 hours for hip fractures in elderly patients. Methods: From May 2017 to April 2018, 47 patients over 75 years old with hip fracture were operated in our hospital and met with inclusion criteria. The patients were divided into two groups: within 48-hour group and over 48-hour group according to study design. In the within 48-hour group, there were 22 patients including 5 males and 17 females, aged from 76 to 97 years, with an average age of 83.6±5.0 years, and there were 10 femoral neck fractures (3 total hip arthroplasty, 7 hemiarthroplasty) and 12 femoral intertrochanteric fractures (proximal femoral intramedullary nail fixation). There were 25 patients (7 males and 18 females) in the over 48-hour group, aged from 76 to 98 years, with an average age of 83.8±5.8 years, and there were 10 femoral neck fractures (2 total hip arthroplasty, 8 hemiarthroplasty) and 15 femoral intertrochanteric fractures (proximal femoral intramedullary nail fixation). At the end of the follow-up period, the clinical data of the two groups were compared. The differences in the length of stay, cost of stay (excluding implants), postoperative complications within 1 month, hip function score (Harris score) within 1 month and 3 months, and mortality within 3 months and at the end of follow-up were analyzed. Results: Both groups were followed up for 12 to 24 months, with an average of 17.7 months. The hospitalization time (7.9±3.0 d), hospitalization expenses (16 627.5±6 428.8 yuan), the incidence of early complications after operation (59.1%) and Harris score (80.9±8.6) in the within 48-hour group were significantly better than those in the over 48-hour group (12.3±4.1 d, 23 799.0±9 785.3 yuan, 88.0%, 71.1±9.2, respectively). At 3 months after operation, there was no significant difference in Harris score between the two groups (83.9±7.3 in within 48-hour group and 82.3±8.9 in over 48-hour group; t=0.668, P=0.507). Within 3 months, there was no death inwithin 48-hour group, but 2 in over 48-hour group; and 1 in within 48-hour group at the last follow-up. Conclusion Elderly patients with hip fracture benefit significantly from surgery within 48 hours after admission.

BACKGROUND:There were stil lacking related clinical researches in the aspects of whether the total blood loss and hidden blood loss were connected with pathogenesis, whether the total blood loss and hidden blood loss were different among the patients who conducted total hip arthroplasty under different pathogenesis, and whether the preoperative intervention should be conducted for a particular cause? OBJECTIVE:To compare and analyze the hidden blood loss of patients with hip osteoarthritis and femoral neck fracture after total hip replacement. METHODS:The clinical data of 150 patients who received the unilateral total hip arthroplasty treatment from June 2013 to January 2015 were colected and analyzed, including 54 patients with hip osteoarthritis (30 male cases and 24 female cases ), 96 patients with femoral neck fracture (41 male cases and 55 female cases). The pre-and post-operative blood routine and intro-and post-operative blood loss and transfusion were recorded, and hidden blood loss during pen-operation period was evaluated. RESULTS AND CONCLUSION:Total blood loss was (1 616±216) mL, hidden blood loss was (699±102) mL, and hidden blood loss accounted for 43.3% of the total blood loss. The total blood loss was (1 742±254) mL in the hip osteoarthritis group, hidden blood loss was (758±127) mL, hidden blood loss accounted for 44.6% of the total blood loss; The average total blood loss was (1 470±189) mL in the femoral neck fracture group, hidden blood loss was (625±98) mL, hidden blood loss accounts for 42.1% of the total blood loss. The total blood loss and hidden blood loss in hip osteoarthritis group were significantly higher than those in the femoral neck fracture group (P< 0.05). However, there was no significant difference on the hidden blood loss accounts for the proportion of the total blood loss between two groups (P=0.419 3). These results suggest that the total blood loss and hidden blood loss are different for the patients who underwent total hip arthroplasty in the premise of both pathogenesis. Therefore, before the total hip arthroplasty, we should fuly take into account the primary cause of patients and estimate the total blood loss and hidden blood loss, so as to take appropriate preventive measures in time to ensure the safety of the replacement process.

Objective To provide anatomical basis for elevating iliac tissue flap pedicled on the iliolumbar artery.Methods The course,number,outer diameter and distribution of iliolumbar artery were observed on 13 human cadavers.Results All the iliolumbar artery originated from the internal iliac artery.The iliolumbar artery gave off 2 branches (iliacus branch and lumbar branch) when passing between the obturator nerve and the lumbosacral trunk,posteriorly to the psoas major.The mean distance between origin of the iliolumbar artery and bifurcation point to iliacus and lumbar branches was 7.1 (7.1 ± 0.5) cm.The iliacus branch divided into two branches:one artery curved forward and anastomosed with the iliacus branch of deep circumflex iliac artery; the other artery supplied the tissue around the posterior superior iliac spine.The lumbar branch supplied the psoas major and the quadratus lumborum.Conclusion The iliolumbar artery and the iliacus branch is one of the most constant and reliable vessels supplying the iliac bone,and can be used as the pedicle of free or pedicled iliac tissue flaps.

Objective To evaluate the effect of anterior minimally invasive plate osteosynthesis (MIPO) for treatment of middle humeral shaft fracture.Methods From November 2011 to March 2014,10 cases of middle humeral shaft fracture were treated using MIPO via the anterior approach (MIPO group).Another 26 cases treated by open reduction and internal fixation (ORIF) of the middle humeral shaft fracture between October 2010 and March 2014 were included as controls (ORIF group).Fracture fixation using the 4.5 mm locking compression plate (LCP) was performed in both groups.Parameter measurements included operative time,intraoperative fluoroscopy times,grafting rate,intraoperative blood loss,postoperative drainage,hospital stay,bone healing time and complications.Results MIPO and ORIF groups differed significantly with respect to intraoperative blood loss [(93.5 ± 25.6) ml vs (325.3 ± 158.3) ml],intraoperative fluoroscopy times [(13.2 ± 6.1) vs 4.0 (0-6.0)] and hospitalization [(11.9 ± 1.7)days vs (18.0 ±4.7)days] (P ＜0.05).Bone grafting and drainage were not performed in MIPO group,while bone grafting rate was 54％ and postoperative drainage volume was (120.4 ± 69.6) ml in ORIF group (P ＜0.05).MIPO and ORIF groups were comparable with respect to operative time [(79.0 ± 22.0) min vs (97.5 ± 30.8) min],bone healing time [(15.2 ± 2.5) weeks vs (18.2 ± 4.8)weeks] and postoperative complications (10％ vs23％) (P＞0.05).Conclusion Anterior MIPO is an effective procedure for treatment of middle humeral shaft fracture,with advantages of small trauma,less bleeding,low risk of nerve injury and high rate of fracture healing.

China ; Communicable Diseases ; Pediatrics ; Societies, Medical

Objective To observe the three-dimensional structure changes of subchondral bone in early stage knee joint instability and the effect of diphosphonate intervention so as to test the role of early three-dimensional structure changes of subchondral bone in pathogenesis of osteoarthritis (OA).Methods Sixty healthy male New Zealand white rabbits were assigned to model group (n =24),diphosphonate group (n=24) and control group (n =12) according to random number table.Rabbit right knee destabilization (anterior cruciate ligament transection) is used to induce OA.Rabbits in diphosphonate group received subcutaneous injection of 0.01 mg/kg diphosphonate (risedronate) per day.Instead,isotonic saline solution of the same volume was subcutaneously given to rabbits in model and control groups.One third of the animals in each group were killed at week 4,8 and 12 respectively.Surgical knee joint with preservation of each 2 cm bone above and below joint surface was dissected to perform Micro-CT.Bone volume fraction (BVF),trabecular thickness (Tb.Th),trabecular spacing (Tb.Sp),trabecular number (Tb.N),volumetric bone mineral density (vBMD) and tissue BMD (tBMD) were measured and analyzed statistically.Results At week 4 following operation,BVF,Tb.N and Tb.Th were lowered significantly in model group as compared to control group (P ＜0.01) ;BVF was lower in model group than in diphosphonate group (P ＜ 0.05) and lower in diphosphonate group than in control group (P ＜ 0.05) ; Tb.Sp was increased in model group as compared to diphosphonate group and control group (P ＜0.01) and had obvious increase in diphosphonate group as compared to control group (P ＜0.01) ; vBMD was significantly lower in model group than in diphosphonate group and control group (P ＜ 0.05),but there was no statistical difference between diphosphonate group and control group.At week 12 following operation,model group presented higher BVF,Tb.Th and Tb.N (P ＜0.05),significantly lower Tb.Sp (P ＜ 0.05) and significantly higher vBMD (P ＜ 0.01) as compared to diphosphonate group and control group.Conclusions In knee joint instability,variations of subchondral bone are mainly characterized by osteoclasia in the early stage,followed by osteogenesis in later stage.Diphosphonate may improve the bone architecture of subcondral bone via inhibition of bone resorption.

Objective To evaluate the outcome of dorsal double locking compression plate (LCP) in treatment of stretched unstable distal radial fractures.Methods Fourteen cases of stretched unstable distal radial fractures were treated by reduction and internal fixation using straight or L-shaped anatomic LCP via dorsal approach.Wrist functional exercise was conducted immediately after operation.Follow up was made after operation to assess motion pain,functional score of wrist,and complication incidence at postoperative 12 weeks,24 weeks,and 1 year.Results Follow-up was lasted for 5-24 months.At postoperative 12 weeks,24 weeks and 1 year,mean visual analogue scale (VAS) was (1.88 ±0.26) points,(0.87 ± 0.14) points and (0.37 ± 0.06) points respectively and wrist functional score (Gartland-Werley score) was (6.45 ± 1.72) points,(2.73 ± 0.52) points and (2.10 ± 0.31) points respectively.According to Garfland-Werley score in the latest follow-up,the results were excellent in 10 cases,good in two,and fair in two.Besides,one case was combined with myotenositis of extensor pollicis longus muscle tendon and another case with myotenositis of extensor tendon.Conclusion Dorsal double LCP is one of the effective methods for stretched unstable distal radial fractures that can reconstruct anatomical structure of the wrist efficiently and attain satisfactory functional recovery,with no obvious pain.

Objective To investigate the initial effect of LARS artificial ligaments arthroscopically in reconstruction of ipsilateral anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL).Methods A total of 21 patients (13 males and 8 females,at average age of 31.5 years) received ACL and PCL restoration using LARS artificial ligaments since June 2006.Preoperative MRI exactly confirmed them as ACL and PCL ruptures.Lysholm score on knee joint was (47.6 ±6.7) points.Surgery had reconstruction of PCL prior to ACL under arthroscope.Results All patients were followed up for average 42 months (range,36-49 months),which showed no infection,ligament rupture,ligament loosening,or other postoperative complications.At postoperative 3 years,Lysholm score was (90.8 ± 3.7) points and International Knee Documentation Committee (IKDC) score was normal in 14 patients,near normal in six,and abnormal in one,with excellent-good rate of 95％.Conclusions LARS artificial ligaments can attain anatomical reconstruction and stability of the knee joint in treatment of ACL and PCL ruptures.Meanwhile,arthroscopic surgery shows superiorities of micro-wound,rapid recovery and satisfactory curative effect.