Objective To analysis the influence of component design and related surgical technique on knee range of motion (ROM) after total knee replacement using Innex knee system. Methods Between September 2003 and December 2005, 88 patients with 98 knees had consecutively undergone posterior cruciate-sacrificing TKA with Innex systems. The posterior condylar offset, post-operative tibial slope and knee ROM were measured in 63 patients (70 knees). The relationship of the change in posterior condylar offset and postoperative tibial slope with knee ROM was assessed using a scatterplot graph and Pearson's regression analysis. According to change of posterior condylar offset, which was measured by postoperative minus preoperative posterior condylar offset, patients were divided into 4 groups. The preoperative body mass index,flexion contracture, knee ROM, HSS score and the postoperative knee ROM of four groups were evaluated.Results The mean knee ROM had improved from 96.2°±11.9° preoperative to 109.8°±13.0° at final followup. The mean pre- and post-operative posterior condylar offset was (24.0±3.5) mm and (24.5±3.3) mm, respectively. The mean postoperative tibial slope was 5.5°±1.8°. There was statistical correlation between the difference in the posterior condylar offset and the change in knee ROM after TKA and no correlation between the postoperative tibial slope and knee ROM postoperatively. The preoperative body mass index, flexion contracture, knee ROM, HSS score did not show difference among four groups. There was a statistically difference in postoperative knee ROM among groups. Conclusion Restoration of posterior condylar offset is important to the maximum range of postoperative knee ROM when Orthopedic surgeons perform TKA with Innex systems.There was no correlation between the postoperative tibial slope and postoperative ROM.

Sixteen goats with fractures of right femur received cortical bone plates allografts on both the sides of femurs. The right allograft strut endured the stimulation of physiological stress, and the left allograft strut did not. Groups of goats were sacrificed and specimens were procured at 3, 6, 12, and 24 week after surgery for histology observation and image analysis of the vessels after Chinese ink perfusion, the rate of bone porosity, the integrated optical density (IOD) of tetracycline fluorescence labeling and new bone formation were investigated in order to evaluate the incorporation of the allograft strut. The allograft strut revascularized at 6 weeks after surgery in the fracture group, but at 3 weeks in the control group. The rate of area of vessels after Chinese ink perfusion, the rate of bone porosity, the integrated optical density (IOD) of tetracycline fluorescence labeling and new bone formation in the fracture group were worse than control from 3 weeks to 6 weeks, but the observed and measured values were better in the fracture group than in the control group beyond 6 weeks after surgery (P < 0.05). The stimulation of stress would be harmful to the allograft strut if the strut endured the stress at an earlier period postoperation. Yet, it would be beneficial to the revascularization, new bone formation, substitution, and internal re-building on the strut provided that the extremity was immobilized for 6 weeks; and if the cortical graft endured the stimulation of physiological stress from 6 weeks postoperation till cancellous conjunction between the ends of fractures, the revascularization on the allograft strut and the bone conjunction between partially allograft strut and host would be faciliated.
Allografts ; Animals ; Biomechanical Phenomena ; Bone Plates ; Bone Transplantation ; Femoral Fractures ; Femur ; physiology ; Goats

The porous scaffolds for bone tissue engineering were prepared by foam impregnation. The magnesium and aluminum acid phosphates were used as bonder and the hydroxyapatite ((Ca10 (PO4)6(OH)2, HA) powder as raw materials. Scanning electron microscopy (SEM) examination indicated that the 3D interconnected porous structure of the organic foam was replicated well by the scaffolds calcined at high temperature and the structural requirement of tissue engineering was satisfied. XRD analysis showed that the scaffold was composed of HA and Ca7Mg2P6O24 while calcined at 1150 degrees C for shorter time and of (Ca, Mg)3(PO4)2 when the time prolonged to 2 h. There was no peak of CaO found in the scaffolds by XRD. According to the culture in vitro, the scaffold possesses good biocompatibility and certain degree of degradability.
Aluminum Compounds ; chemistry ; Biocompatible Materials ; Bone Substitutes ; chemistry ; Calcium Phosphates ; chemistry ; Durapatite ; chemistry ; Phosphates ; chemistry ; Porosity ; Tissue Engineering

OBJECTIVETo compare the influence of normal and degenerative discs on stress distribution of the thoracolumbar vertebrae under destructive load, explore the biomechanical background and clinical meaning and provide theoretical basis for clinical diagnosis and treatment.

METHODSA mechanical model of thoracolumbar motion segment of normal and degenerative discs was built with a three dimensional finite element method and three stresses of vertical compression, compressive flexion and distractive flexion were comparatively analyzed.

RESULTSWith vertical compression and compressive flexion loads, the thoracolumbar motion segment of the normal disc showed that the central part of the upper and lower end-plates of the vertebrae and the central part of the trabecular bone adjacent to the end-plate were loaded with the most intensive stresses, meanwhile, the postero-lateral part of the annulus fibrosus was concentrated with stresses. Degenerative disc showed that the stress distribution of the trabecular bone was relatively averaged, the stresses of the central part adjacent to the end-plate were low, while at the same time, the stresses of the peripheral part were elevated relatively. With distraction flexion load, the stresses of the cortex bone, trabecular bone, end-plate and annulus fibrosus of the thoracolumbar vertebrae of degenerative discs were low, meanwhile, the stresses of the posterior structure of the vertebral body were relatively elevated compared with that of normal discs.

CONCLUSIONSThere is difference in influence between normal and degenerative discs on the stress distribution of the thoracolumbar vertebrae with destructive load. The transferring way of load is changed after disc degeneration.

Elasticity ; Finite Element Analysis ; Humans ; Lumbar Vertebrae ; physiology ; Spinal Injuries ; physiopathology ; Stress, Mechanical ; Tensile Strength ; Thoracic Vertebrae ; physiology

OBJECTIVETo provide theoretical basis for effect and mechanism of percutaneous lumbar discectomy in clinic.

METHODSA total of 180 patients with lumbar intervertebral disc herniation were evaluated by CT on the fifth day before and after operation. Meanwhile, CT value was measured in the determined level and region.

RESULTSAfter operation, CT value of the central and posterior determined point of herniated intervertebral disc was lower significantly than that before operation (P<0.01), but CT value of the anterior determined point was different insignificantly. The excellent and good results of the patients together were 83% postoperatively.

CONCLUSIONSThe curative effect of percutaneous lumbar discectomy is achieved through reduction of lumbar intradiscal pressure.

Adult ; Diskectomy, Percutaneous ; Female ; Humans ; Intervertebral Disc Displacement ; diagnostic imaging ; surgery ; Lumbar Vertebrae ; diagnostic imaging ; Male ; Middle Aged ; Tomography, X-Ray Computed ; Treatment Outcome

Objective:To analyze the clinical efficacy of internal fixation and prosthesis revision in the treatment of periprosthesis fracture after total knee arthroplasty.Methods:A total of 35 patients (35 knees) with periprosthetic fractures after total knee arthroplasty were retrospectively analyzed from January 2008 to January 2022 in the Department of Orthopaedics, West China Hospital, Sichuan University, including 13 males and 22 females, aged 71.4±4.1 years (range, 62-81 years). Left knee 19 cases, right knee 16 cases. There were 20 cases of Rorabeck type II and 15 cases of Rorabeck type III. The initial replacement was performed using a fixed platform post-stabilized knee prosthesis, which was fixed with bone cement. Patients with Rorabeck type II were treated with internal fixation alone (internal fixation group) and patients with Rorabeck type III underwent revision with replacement prosthesis (revision group). The Hospital for Special Surgery (HSS) score, range of motion (ROM) of knee joint, alignment of lower extremity and incidence of postoperative complications were compared between the two groups.Results:All patients successfully completed the operation and were followed up for 5.2±3.6 years (range, 1-12 years). Intraoperative blood loss was 680±102 ml (range, 420-1100 ml). The operative time in the internal fixation group was 105±17 min, which was less than 140±21 min in the revision group, and the difference was statistically significant ( t=-5.450, P<0.001). There was no complication of nerve or blood vessel injury during the operation. Five cases in the internal fixation group had unsatisfactory lower extremity force lines (>3° deviation from normal) after surgery, and all lower extremity force lines in the revision group were satisfied, and the difference in the satisfaction rate of lower extremity force lines between the two groups was not statistically significant ( P=0.057). The fracture healing time, knee ROM and HSS scores at the last follow-up were 5.1±1.3 months, 86°±5° and 84±5 in the internal fixation group and 4.8±1.5 months, 83°±6° and 82±4 in the revision group. One case in the revision group was diagnosed postoperatively with periprosthetic infection with pathogen culture suggestive of Candida albicans, recurrent anterior knee sinus tracts and patellar ectasia, which progressed to osteomyelitis, and mid-thigh amputation was performed 1 year after revision. Conclusion:The stability of prosthesis is an important reference for the treatment of periprosthetic fractures after total knee arthroplasty. Strong internal fixation in patients with unloosened prosthesis and revision with replacement of prosthesis in patients with loose prosthesis can achieve good knee joint function.

Objective:To analyze the medium- and long-term outcomes of V-Y quadricepsplasty in primary total knee arthroplasty (TKA) to expose an ankylosed or stiff knee joint.Methods:From May 2010 to February 2019, a total of 12 patients with TKA revealed by V-Y quadricepsplasty in West China Hospital of Sichuan University due to knee ankylosis or stiffness were retrospectively analyzed, including 7 males and 5 females, aged (53.9±14.9) years (range, 24 to 72 years), 6 patients on the left side and 6 patients on the right side. Preoperative diagnosis: 7 cases of osteoarthritis, 2 cases of rheumatoid arthritis, 1 case of traumatic arthritis, and 2 cases of haemophilic arthritis. Visual analogue scale (VAS), range of motion, quadriceps muscle strength, Knee Society score (KSS) and postoperative complications were recorded before and after operation.Results:All patients successfully completed the operation and were followed up for 102.2±31.1 months (range, 51-141 months). The operation time was 87.0±15.7 min (range, 73 to 123 min), the intraoperative blood loss was 823.6±237.7 ml (range, 555 to 1 471 ml), and the hospital stay was 13.3±6.3 d (range, 6 to 28 d). Postoperative VAS scores were decreased in all patients, and the difference before and after operation was statistically significant ( F=132.000, P<0.001). The VAS scores at 3 months and the last follow-up were 2.2±0.7 points and 1.2±0.4 points, respectively, lower than those before operation (5.2±0.7 points), and the difference was statistically significant ( P<0.05). KSS knee scores were higher in all patients after operation, and the difference was statistically significant before and after operation ( F=40.960, P<0.001). KSS knee scores at 3 months and the last follow-up were 56.0±14.1 points and 74.3±16.1 points, respectively, higher than those before operation (26.1±7.8 points), and the difference was statistically significant ( P<0.05). Postoperative KSS functional scores were increased in all patients, and the difference before and after operation was statistically significant ( F=24.332, P<0.001). The KSS functional scores at 3 months and the last follow-up were 52.9±19.4 points and 79.2±19.6 points, respectively, higher than those before operation (27.1±15.6 points), and the difference was statistically significant ( P<0.05). Postoperative knee joint motion was increased in all patients, and the difference was statistically significant before and after operation ( F=24.145, P<0.001). The range of motion of the knee joint at 3 months and the last follow-up was 57.5°±22.2° and 70.0°±25.9°, respectively, which was higher than the preoperative 12.5°±14.1°, and the difference was statistically significant ( P<0.05). Preoperative quadriceps muscle strength was grade 3 in 2 cases and grade 4 in 10 cases; at the last follow-up, grade 4 in 1 case and grade 5 in 11 cases, and the muscle strength was improved compared with that before operation, the difference was statistically significant ( Z=11.000, P<0.001). At the last follow-up, there were no complications such as wound seepage, delayed healing, superficial or deep soft tissue infection, periprosthesis infection and loosening, deep vein thrombosis and pulmonary embolism. Conclusion:In patients with ankylosed or stiff knee receiving TKA, the use of V-Y quadricepsplasty can increase the exposure, thereby improving the range of knee motion and quadriceps muscle strength.

Objective To investigate the clinical characteristics and therapeutic methods of bac-terial colonization and infection of Acinetobacter baumannii on the wound of earthquake induced patients. Methods A retrospective study was done on 42 Wenehuan earthquake induced patients with positive wound germiculture of Acinetobacter baumannii. There were 24 males and 18 females, at mean age of 37 years (12-96 years). Open injury was located at the upper arm in one patient, at the forearm in four, at the thigh in 12, at the calf in 23 and at the trunk in two. The time between injury and treatment varied from 3 to 7 days. The clinical characteristics including the bacteria identification and drug sensitivity test were studied to compare drug resistance to 15 antibiotics. Results Bacterial colonization of Acineto-bacter baumannii was found in 31 patients (8.2%) and infection of Acinetobacter baumannii in 11 (2.9%). After debridement, pruphylactic antibiotics and nutrition support, 15 patients with bacterial colonization were managed with Ⅱ stage suture or skin grafting. The other 16 patients were transferred to hospitals of other provinces after germiculture turned negative. Through debridement and drainage, antibi-otic therapy and nutrition support, the infection was controlled and the wound eliminated in six patients through Ⅱ stage suture but four were concomitant with pulmonary infection and one with septicemia. Drug sensitivity test showed that sensitive rate to imipenem, amikacin, levofloxacin, ticarcillin-clavulanic acid, tobramycin were 59.5%, 21.4%, 21.4%, 19.5% and 19.0% respectively. Conclusions The risk factors of infection of Acinetobacter baumannii include severe tissue trauma, severe wound contamination, delayed treatment and weak body resistance. During treatment, the bacterial colonization and infection of Acinetobacter baumannii should be distinguished and treated respectively. Correct wound treatment, suit-able antibiotic therapy and increased body resistance are key to improvement of clinical curative effect.

Objective To investigate the influencing factors for trauma-induced tibia1 infection in underground coal mine.Methods A retrospective analysis was performed for the clinical data of 1 090 patients with tibial fracture complicated by bone infection who were injured in underground coal mine and admitted to our hospital from January 1995 to August 2015,including the type of trauma,injured parts,severity,and treatment outcome.The association between risk factors and infection was analyzed.Results Among the 1 090 patients,357 had the clinical manifestations of acute and chronic bone infection,219 had red and swollen legs with heat pain,and 138 experienced skin necrosis,rupture,and discharge of pus.The incidence rates of tibial infection from 1995 to 2001,from 2002 to 2008,and from 2009 to 2015 were 31％,26.9％,and 20.2％,respectively.The incidence rate of bone infection in the proximal segment of the tibia was significantly higher than that in the middle and distal segments (42.1％ vs 18.9％/27.1％,P＜0.01).As for patients with different types of trauma (Gustilo typing),the patients with type Ⅲ fracture had a significantly higher incidence rate of bone infection than those with type Ⅰ/Ⅱ infection (52.8％ vs 21.8％/24.6％,P＜0.01).The incidence rates of bone infection after bone traction,internal fixation with steel plates,fixation with external fixator,and fixation with intramedullary nail were 20.7％,43.5％,21.4％,and 26.1％,respectively,suggesting that internal fixation with steel plates had a significantly higher incidence rate of bone infection than other fixation methods(P＜0.01).The muhivariate logistic regression analysis showed that the position of tibial fracture and type of fracture were independent risk factors for bone infection.Conclusion There is a high incidence rate of trauma-induced tibial infection in workers in underground coal mine.The position of tibial fracture and type of fracture are independent risk factors for bone infection.Vacuum sealing drainage and Ilizarov technique can achieve a satisfactory therapeutic effect.

Objective To investigate the influencing factors for trauma-induced tibia1 infection in underground coal mine.Methods A retrospective analysis was performed for the clinical data of 1 090 patients with tibial fracture complicated by bone infection who were injured in underground coal mine and admitted to our hospital from January 1995 to August 2015,including the type of trauma,injured parts,severity,and treatment outcome.The association between risk factors and infection was analyzed.Results Among the 1 090 patients,357 had the clinical manifestations of acute and chronic bone infection,219 had red and swollen legs with heat pain,and 138 experienced skin necrosis,rupture,and discharge of pus.The incidence rates of tibial infection from 1995 to 2001,from 2002 to 2008,and from 2009 to 2015 were 31％,26.9％,and 20.2％,respectively.The incidence rate of bone infection in the proximal segment of the tibia was significantly higher than that in the middle and distal segments (42.1％ vs 18.9％/27.1％,P＜0.01).As for patients with different types of trauma (Gustilo typing),the patients with type Ⅲ fracture had a significantly higher incidence rate of bone infection than those with type Ⅰ/Ⅱ infection (52.8％ vs 21.8％/24.6％,P＜0.01).The incidence rates of bone infection after bone traction,internal fixation with steel plates,fixation with external fixator,and fixation with intramedullary nail were 20.7％,43.5％,21.4％,and 26.1％,respectively,suggesting that internal fixation with steel plates had a significantly higher incidence rate of bone infection than other fixation methods(P＜0.01).The muhivariate logistic regression analysis showed that the position of tibial fracture and type of fracture were independent risk factors for bone infection.Conclusion There is a high incidence rate of trauma-induced tibial infection in workers in underground coal mine.The position of tibial fracture and type of fracture are independent risk factors for bone infection.Vacuum sealing drainage and Ilizarov technique can achieve a satisfactory therapeutic effect.