Fan Liu

Nantong University, Tungchow, Jiangsu Sheng, China

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Publications (16)17.75 Total impact

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    ABSTRACT: The aim of this study was to compare the efficacy of vacuum assisted closure (VAC) with standard moist wound care (SMWC) in surgical site infection after ankle surgery. A prospective cohort was performed among patients with surgical site infection after ankle surgery between 2012 and 2013. The follow-up period was three month, and the efficacy end point was complete wound closure rate. Ninety-four patients were analyzed, with 61 patients in the VAC group and 33 in the SMWC group. The complete wound closure rate in the VAC group was higher than that in the SMWC group at 3 month follow up (90.2% Vs. 72.7%, p = 0.028). The median time to complete wound closure was 31 days (95% CI 20.2-41.8) for VAC, and 63 days (95% CI 46.9-79.1) for SMWC (χ(2) = 4.023, p = 0.045). In the superficial infection subgroup, the median times to complete wound closure were 20 days (95% CI 14.2-35.1) in the VAC group and 42 days (95% CI 35.4-69.4) in SMWC group (χ(2) = 4.331, p = 0.041). In the deep subgroup, the median times to complete wound closure were 46 days (95% CI 28.2-65.9) in the VAC group and 75 days (95% CI 43.2-79.6) in SMWC group (χ(2) = 6.475, p = 0.026). Our result showed that vacuum assisted closure was more effective than standard moist wound care in surgical site infection after ankle surgery. Copyright © 2015 Surgical Associates Ltd. Published by Elsevier Ltd. All rights reserved.
    International Journal of Surgery (London, England) 03/2015; 17. DOI:10.1016/j.ijsu.2015.03.008 · 1.65 Impact Factor
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    ABSTRACT: Objective Evidence shows obesity is an important risk factor for knee osteoarthritis (OA). However, the dose-response relationship between body mass index (BMI) and knee OA risk is unclear. The purpose of the current study is to establish a nonlinear dose-response relationship between BMI and risk of knee OA.Methods The electronic database of PubMed, Web of Science, and translating research into practice (TRIP) database were searched. Observational studies for BMI and knee OA risk were included. Restricted cubic splines and generalized least-squares regression methods were used to model a potential curvilinear relationship and to make a dose-response meta-analysis.ResultsA total of 12 studies were included in the meta-analysis. A non-linear dose-response association between BMI and risk of knee OA was significant (P = 0.001). The relative risks were 1.59 (95% CI: 1.34-1.81), 3.55 (95% CI: 2.51-5.11), and 7.45 (95% CI: 4.19-13.13) when BMI was at the point of 25, 30, and 35 kg/m2 compared with reference (22.5 kg/m2, the median value of the lowest category), respectively. Non-linear dose-response association was also significant in male and female subgroup. In male subgroup, the relative risks were 1.39 (95% CI: 0.99-1.92), 3.41 (95% CI: 2.07-5.48), and 5.71 (95% CI: 3.12-9.95) when BMI was at the point of 25, 30, and 32.5 kg/m2 compared with reference, respectively. In female subgroup, the relative risks were 1.72 (95% CI: 1.51-1.99), 3.51 (95% CI: 2.65-4.51), and 4.72 (95% CI: 3.25-6.91) compared with reference when BMI was at the point of 25, 30, and 32.5 kg/m2 compared with reference, respectively. Modest publication bias was found in the meta-analysis. However, sensitivity analysis showed a high stability for the result.Conclusions The meta-analysis indicated that knee OA risk increased almost exponentially according with the increase of body mass index. Knee OA prevention will benefit from weight control.
    Obesity 10/2014; 22(10). DOI:10.1002/oby.20835 · 4.39 Impact Factor
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    ABSTRACT: Heparanase (HPSE) is a type of endoglycosidase that decomposes the heparan sulfate (HS) lateral chains of heparan sulfate proteoglycans (HSPGs), releases related growth factors and participates in angiogenesis and bone formation. HPSE is expressed in osteoblasts and is involved in fracture healing. However, the role of HPSE in osteogenic differentiation requires in-depth investigation. To investigate the expression of HPSE in the osteogenic differentiation of rat marrow stromal cells (MSCs), the protein and mRNA expression levels of HPSE on days 0, 1, 3, 7, 10, 14 and 21 of osteogenic differentiation of MSCs in 2- and 10-month-old rats were detected using western blotting and reverse transcription-polymerase chain reaction (RT-PCR), respectively. From the third day of osteogenic differentiation onwards, all HPSE protein and mRNA expression levels in 2-month-old rats were significantly increased compared with basal levels (days 0 and 1; P<0.05). The protein and mRNA expression levels reached a peak on days 10 and 14, respectively, followed by a gradual decline. The same pattern was observed in 10-month-old rats; however, when compared with with basal levels, the differences were not statistically significant (P>0.05). The protein and mRNA levels of HPSE in the 2-month-old rats were significantly higher compared with the respective levels in the 10-month-old rats (P<0.05). HPSE is involved in the osteogenic differentiation of rat MSCs. The protein and mRNA expression levels of HPSE in aged rats are weaker compared with those in young rats, which may be related to the declined osteogenic differentiation ability.
    Experimental and therapeutic medicine 06/2013; 5(6):1697-1700. DOI:10.3892/etm.2013.1070 · 0.94 Impact Factor
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    ABSTRACT: . To compare two internal fixation devices clinically in stabilisation of intertrochanteric femur fractures. . Eighty-seven patients were randomised upon their admission to the hospital using a sealed envelope method. Forty-five were treated with proximal femur nail antirotation (PFNA) and 42 with reverse less invasive stabilisation system (LISS). The perioperative data were recorded and compared in relation to fracture type. . In each type of fractures, no significant differences were found with respect to the blood loss, the quality of reduction, the time to bony healing, and the Harris hip score between the 2 groups. The mean duration of surgery was significantly longer in reverse LISS group than in PFNA group. . Both the PFNA and the reversed LISS are effective in the treatment of different types of intertrochanteric femur fractures. PFNA is superior to reverse LISS in terms of surgical time, weight-bearing, and perhaps fluoroscopy time.
    The Scientific World Journal 01/2013; 2013:834825. DOI:10.1155/2013/834825 · 1.73 Impact Factor
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    ABSTRACT: Peroxisome proliferator-activated receptor-γ (PPAR-γ) has been found to play an essential role in cell proliferation, but whether it was involved in Schwann cells differentiation has never been studied. We have found in sciatic nerve injury that expression of PPAR-γ decreases mainly in Schwann cells, and it was also increased in differentiated Schwann cells. Further, activated PPAR-γ by the endogenous ligand 15 d-PGJ(2) increased expressions of PPAR-γ level and Schwann cell differentiation, and this effect may be protected by its antagonist GDW9662. These results indicate that PPAR-γ could promote Schwann cell differentiation, which plays an important role in peripheral nerve injury and regeneration.
    Journal of Molecular Neuroscience 11/2011; 47(2):380-8. DOI:10.1007/s12031-011-9662-8 · 2.76 Impact Factor
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    ABSTRACT: To investigate the effect of timing of surgery on clinical results and perioperative complications in pediatric patients with Gartland III type supracondylar humeral fractures without neurovascular compromise. Eighty-six consecutive children treated surgically at our hospital from April 2005 to June 2007 for displaced supracondylar humeral fractures were reviewed. All these patients were treated by the same group of doctors. The children were divided into two groups: early if treated within 12 hours after injury and delayed if treated later than that. Perioperative complications and clinical results, especially for open surgery, were compared between the two groups. Forty pediatric patients underwent surgery in the early group and 46 in the delayed group. There were no significant differences between the two groups in perioperative complications such as pin tract infection, iatrogenic nerve injury, compartment syndrome and conversion to open surgery. For open surgery, both the clinical results and perioperative complications were not affected by delaying for more than 12 hours after injury. However, blood loss and operation time were greater in the early than in the delayed group, possibly due to relatively more edema. Delay in surgery, regardless of whether it is closed or open, for more than 12 hours after injury does not influence the perioperative complications and clinical results for displaced supracondylar humeral fractures in children. However early open reduction and pinning may increase intra-operative blood loss and take longer.
    Orthopaedic Surgery 11/2011; 3(4):242-6. DOI:10.1111/j.1757-7861.2011.00153.x
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    ABSTRACT: To evaluate the clinical effects of surgical treatment for open dislocation of talus. From June 2001 to July 2008,the complete data of 11 patients with open dislocations of talus were retrospectively analyzed, including 8 males and 3 females with an average age of 39.5 years (ranged 19 to 52). According to Gustilo typing, type I was in 2 cases, type II in 6 cases, type III A in 2 cases, type III B in 1 case. Five cases were tibial astragaloid joint dislocation in which 3 cases associated with subtalar joint dislocation, 4 cases were subtalar joint dislocation and 2 cases were total dislocation of talus. Among them, 8 dislocations associated with talus fractures. All patients were treated with debridement, open reduction, internal fixation with K-wires or screws and external fixation with plaster or external fixator within 8 hours after injury. External fixations were removed at 6 weeks after operation. Partial weight bearing was permitted only when X-rays indicated bony healing. Clinical effects were evaluated according to AOFAS system and X-ray films during follow-up. The mean time of follow-up was 13.8 months(ranged 10 to 15 months). Eight patients with fractures obtained bone healing in 4-7 months with an average of 4.3 months. No infection of wound or deep tissue was found. At final follow-up, talus necrosis was in 2 cases and traumatic arthritis was in 2 cases. The AOFAS score was 71.3 +/- 8.6, among the total, the pain, function, alignment was respectively (32.4 +/- 7.1), (31.0 +/- 15.7), (7.6 +/- 2.3) scores. Complete debridement may avoid infection in treating open dislocation of talus, early reduction and fixation is a key point during treatment.
    Zhongguo gu shang = China journal of orthopaedics and traumatology 07/2011; 24(7):597-9.
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    ABSTRACT: Controversy persists concerning the preferred treatment of peritrochanteric femoral fractures. The purpose of the present study was to evaluate the mid-term outcomes of the newly developed implants - proximal femoral nail antirotation (PFNA) for the stabilisation of this type of fracture. Between April 2006 and March 2008, 169 patients with peritrochanteric femoral fractures were treated with PFNA. As many as 26 patients were excluded from the study. According to the Orthopaedic Trauma Association (OTA) classification system, the remaining 143 fractures were classified as 19 cases of AO/OTA 31A1 fractures, 83 cases of 31A2 fractures, 28 cases of 31A3 fractures and 13 cases of 31A combined with proximal 32 fracture or separate proximal 32 fracture. The mean age of these patients was 67 years (range, 20-93 years). The operative time, the overall fluoroscopy time, the duration of hospitalisation and the surgical complications were noted. Patients were followed up for a mean of 21 months (range, 12-36 months). Functional outcomes were assessed according to the Harris hip scoring system. Fifteen patients (10%) required open reduction. The mean duration of surgery (from the beginning of close reduction to wound closure) was 72 min with a range between 45 and 170 min. The mean fluoroscopy time was 164 s with a range between 92 and 396 s. The mean time of hospital stay was 15 days. Postoperative X-rays showed a good or acceptable reduction in 134 cases (94%), and an ideal implant position in 131 cases (92%). There were 12 (8%) postoperative complications. All patients except one healed their fractures without any implant-specific complication (bending, breaking of the implant, cut out of the PFNA blade, femoral head penetration of the blade or ipsilateral fractures of the femoral shaft at the tip of the implant). The average time to bone healing was 16 weeks (range, 12-25 weeks). At the time of the latest follow-up, 106 patients (74%) were restored to their preoperative mobility. The mean Harris hip score was 84 points (range, 46-100 points). A total of 106 patients (74%) had an excellent or good outcome. According to the patients and/or their caregivers, outcome was described as satisfactory in 120(84%) of the 143 patients, and 36(90%) of the 40 patients, who were more than 80 years old. The results suggest that PFNA is a very effective and safe method in the treatment of different patterns of peritrochanteric femoral fractures. The fixation is adequate to maintain reduction over time even in osteoporotic bones.
    Injury 08/2010; 41(8):810-7. DOI:10.1016/j.injury.2010.03.020 · 2.46 Impact Factor
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    ABSTRACT: To investigate the effects of serum cobalt ion concentration on the liver, kidney and heart in mice. Forty 4-week-old male ICR mice were randomly divided into four groups (n = 10 in each group) as follows: Group 1 (HD), high-dose cobalt chloride group (3.28 mg/kg/day); Group 2 (MD), medium-dose cobalt chloride group (1.64 mg/kg/day); Group 3 (LD), low-dose group cobalt chloride group (0.82 mg/kg/day); and Group 4 (NC), normal control group (vehicle). Cobalt chloride and normal saline were given by intraperitoneal injection once per day for 3 weeks. The body weights of the mice were recorded every 3 days to ensure the correct doses of cobalt chloride. Blood samples for testing were taken at day 4, week 1, week 2 and week 3. Serum cobalt ion concentrations were measured in all samples whereas other serum biochemical variables, including aspartate aminotransferase (AST), aspartate aminotransferase (ALT), blood urea nitrogen (BUN), creatinine (Cr), and creatine kinase (CK) were evaluated at week 1, 2 and 3. After killing the mice at week 3, the heart, liver and kidney were collected for pathological evaluation. Serum cobalt ion concentration was different between the groups. High-dose cobalt chloride significantly increased AST, ALT and CK concentrations, the concentrations increasing in parallel with treatment duration. Pathological evaluation showed that high-dose cobalt chloride had toxic effects on the heart and liver; however no significant effect was apparent in the kidney. High-dose cobalt ion concentration in serum has toxic effects on the heart and liver, but no significant effect on the kidney in mice.
    Orthopaedic Surgery 05/2010; 2(2):134-40. DOI:10.1111/j.1757-7861.2010.00076.x
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    ABSTRACT: To compare the immediate stability of different fixation techniques for the direct repair of spondylolytic defects in the pars interarticularis. Eight fresh-frozen and thawed calf cadaveric lumbar spines were used for mechanical testing. A modified Scott, screw-rod-hook, screw-rod construct fixation and Buck techniques were applied to calf lumbar spines in which bilateral spondylolytic defects had been created in the L(4) vertebra. The multidirectional flexibility of each specimen was measured under flexion/extension, right/left lateral bending, and right/left axial rotation. After creating a pars interarticularis defects at L(4), the range of movement (ROM) at both the L(3)-L(4) and L(4)-L(5) levels were increased under all loading conditions. Each fixation technique significantly increased stability and almost restored intervertebral rotation mobility to normal levels. Under flexion-extension, the screw-rod-hook and screw-rod construct techniques of fixation provided more rotational stability than did the other two techniques (P < 0.05). The screw-rod-hook, screw-rod construct and Buck techniques also provided more flexion/extension stability than the modified Scott technique. The current study has shown that the ROM at the involved and upper adjacent level of spondylolysis is greater than in the intact spine. All four fixation techniques accorded with spinal biomechanical principles and restored intervertebral rotation displacements under flexion, rotation and bending loads to the intact condition. The screw-rod-hook and screw-rod construct fixation techniques provided more stability than did the modified Scott and Buck techniques, and are therefore good prospects for direct repair.
    Orthopaedic Surgery 02/2010; 2(1):46-51. DOI:10.1111/j.1757-7861.2009.00064.x
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    ABSTRACT: To discuss the classification, management and outcome of fractures of the ulnar coronoid process. Retrospective analysis was carried out in 31 patients (19 men and 12 women of average age 29.8 years [range, 18-52 years]) with fractures of the ulnar coronoid process. The fractures were classified into four major groups based on the extent of injury to the ulnar coronoid process, the state of the anterior bundle of the ulnar collateral ligaments (UCL) and elbow stability. A fracture of the coronoid process less than halfway up was defined as type I (eleven cases); of the middle of the coronoid process with injury of the UCL as type II (nine cases); of the base of coronoid process with dislocation of the elbow joint, sometimes with injury of the UCL, as type III (six cases); and severe comminuted fracture of the coronoid process with elbow instability as type IV (five cases). We chose treatment according to the type of injury. Follow-up was 18-72 months (average 28.6 months). All patients achieved fracture union without inflammation, neural injuries or elbow instability. One type III and two type IV patients had traumatic osteoarthritis, and two type III and two type IV developed heterotopic ossification. There was a statistically significant difference between the ranges of movement of the two-side joints in type IV. We choose conservative treatment for type I fractures unless the bone fragment affected movement of the elbow joint, in which case we chose operative treatment so that elbow stability was not affected. Type II and type III fractures with elbow instability were reduced by internal fixation and the ligament repaired or reconstructed. In type IV cases, bone reconstruction was necessary to recover elbow stability. Proper post-operative rehabilitation can decrease the occurrence of traumatic osteoarthritis.
    Orthopaedic Surgery 11/2009; 1(4):269-74. DOI:10.1111/j.1757-7861.2009.00042.x
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    ABSTRACT: The purpose of present study was to evaluate the role of LISS after a large series of patients in whom a fracture around the knee had been treated with this uniform technique. Between April 2004 and September 2006, 210 patients with a total of 216 fractures around the knee were treated with LISS, all at the Affiliated Hospital to Nantong University. Patients were followed for a mean of 27 months (range 12-42 months). 26 patients were excluded from the study. The remaining 184 patients with a total of 189 fractures of either distal femur (85 cases) or proximal tibia (104 cases) were available for analysis. The mean age of these patients was 49 years (range 18-82 years). Immediate postoperative X-rays showed the alignment of bone and joint was satisfactorily maintained with LISS in all cases and an ideal implant position in 176 cases (93%). All cases healed the fracture without non-union. The mean time to union was 15 weeks (range 12-27 weeks) for the femoral and 16 weeks (range 12-27 weeks) for the tibia fractures. Functional assessment was performed using HSS (hospital for special surgery) score. At the time of the latest follow-up, 158 patients (86%) had an excellent or good outcome. Overall, 3 patients were subject to a salvage operative procedure due to implant failure. Three cases underwent secondary bone graft for open fractures. Superficial and deep infection was found each in one patient and both were treated successfully. Hardware prominence irritation was found in 2 patients. LISS was removed in 27 patients after bone healing, and this procedure was neither less invasive nor easy as imagined. The results indicate the LISS system is perfect but by no means unique in the treatment of the fractures around the knee. The fixation is adequate enough to maintain alignment and obtain union with a low incidence of complications even in patients with osteoporotic bone. We firmly believe favourable results can be achieved when this device is combined with correct indications as well as skillful techniques.
    Injury 07/2009; 40(11):1187-94. DOI:10.1016/j.injury.2009.03.012 · 2.46 Impact Factor
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    ABSTRACT: The aim of the study was to evaluate the biomechanical performance and clinical results of TSRH's Hook plus screw fixation after direct repair of spondylolysis defects in the pars interarticularis. Biomechanical testing of eight calf cadaver lumbar spines were used to provide comparative biomechanical data on TSRH's Hook plus screw fixation, and for the intact and the destabilized spondylolytic spines, modified Scott's fixation, screw-rod construct and Buck's fixation were used. Eleven patients with bilateral spondylolysis were treated with segmental TSRH's Hook plus screw fixation and autogenous bone graft; after an average follow-up period of 28 months, the patients were reviewed. Conventional tomography and computed tomography scans were taken to assess the condition of the fixation and the healing of the bony defect separately. MR images were performed to assess the adjacent disk conditions. MacNab criteria were used to assess their pre- and postoperative status. Each fixation technique significantly increased stiffness and returned the intervertebral rotation stiffness nearly to intact levels. TSRH's Hook plus screw technique and screw-rod construct provided more rotational stability than the other two techniques. TSRH's Hook plus screw, pedicle rod construct and Buck's technique also provided more flexion/extension stability than the modified Scott's technique. Neither complications nor instrumentation failure was observed. Retrospective follow-up of patients showed complete radiographic healing but unilateral nonunion in one on CT scans and pain relief in all patients. MR images of lumbar spine showed no significant change of disk before and after the surgery. Excellent or good results were obtained in ten cases according to MacNab criteria, but fair results were obtained in case of unilateral nonunion. Biomechanical evaluation of the TSRH's Hook plus screw fixation showed excellent stability of the lumbar vertebrae. Excellent clinical results show direct repair of spondylolysis by TSRH's Hook plus screw fixation and bone grafting would be the alternative for treating patients with persistent back pain after 6 months of conservative treatment.
    Archives of Orthopaedic and Trauma Surgery 06/2009; 130(2):209-15. DOI:10.1007/s00402-009-0897-6 · 1.36 Impact Factor
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    ABSTRACT: To evaluate the clinical outcome of dual plating in the treatment of humeral intercondylar type-C fractures in adults. From June 2004 to October 2007, 38 cases of type-C distal humeral fractures were stabilised with dual plating. There were 21 males and 17 females. The average age was 43 years with a range from 21 to 71 years. According to the AO classification, 9 cases were of type C1, 17 of C2 and 12 of C3. The posterior midline approach was selected. Twenty-one cases were exposed through the trans-olecranon osteotomy, 11 through the Campbell (Van Gorder) approach, 6 through triceps sparing approach. Autogenous bone graft was performed in 5 cases because of severe comminution. Thirty-five patients were followed-up for 14-30 months (mean 24.2 months). At the latest follow-up, the elbow flexion averaged 119 degrees (range 90 degrees - 135 degrees ), and the loss of extension averaged 16.2 degrees (range 5 degrees - 25 degrees ). All the patients got bony healing, the average healing period was 14 weeks. The patients were evaluated using the criteria of Aitken and Rorabeek and the scores were 13 excellent, 16 good, 6 fair. Twenty-nine patients (82.9%) had a good or excellent results. Complications included 4 cases of traumatic osteoarthritis, 2 heterotopic ossification, 1 ulnar neuropathy. Infection as well as loosening or breakage of the implant was not found. The dual plating is able to provide rigid fixation for the humeral intercondylar fractures. In addition, it can allow early functional exercise after operation, decrease the related complications significantly, and improve the functional results.
    Zhonghua wai ke za zhi [Chinese journal of surgery] 06/2009; 47(12):892-5.
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    ABSTRACT: To determine whether an adenoviral construct containing bone morphogenetic protein-4 (BMP-4) gene can be used for lumbar spinal fusion. Twelve New Zealand white rabbits were randomly divided into two groups, 8 in the experimental group and 4 in the control group. Recombinant, replication-defective type 5 adenovirus with the cytomegalovirus (CMV) promoter and BMP-4 gene (Ad-BMP-4) was used. Another adenovirus constructed with the CMV promoter and beta-galactosidase gene (Ad-beta-gal) was used as control. Using collagen sponge as a carrier, Ad-BMP-4 (2.9 multiply 10(8) pfu/ml ) was directly implanted on the surface of L(5)-L(6) lamina in the experimental group, while Ad-beta-gal was implanted simultaneously in the control group. X-ray was obtained at 3, 6, and 12 weeks postoperatively to observe new bone formation. When new bone formation was identified, CT scans and three-dimensional reconstruction were obtained. After that, the animals were killed and underwent histological inspection. In 12 weeks after operation, new bone formation and fusion were observed on CT scans in the experimental group, without the evidence of ectopic calcification in the canal. Negative results were found in the control group. Histological analysis demonstrated endochondral bone formation at the operative site and fusion at early stage was testified. In vivo gene therapy using Ad-BMP-4 for lumbar posterolateral spinal fusion is practicable and effective.
    Chinese Journal of Traumatology (English Edition) 05/2007; 10(2):72-6.
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    ABSTRACT: To evaluate the biomechanical effect and clinical results of hook screw fixation after direct repair of lumbar spondylous defects in the pars interarticularis. L(2)-L(6) spines of 8 fresh-frozen and thawed calf cadavers were used for mechanical testing. Bilateral spondylous defects were created in the L(4)vertebra. The intervertebral rotation ranges between L(4) and L(5) were scanned and computerized in various states of motion, such as flexion/extension, lateral bending and torsional loadings applied on the intact spine and the spondylous spine when the spondylous spine was fixed with modified Scott's fixation, hook screw fixation and Buck's fixation sequentially and respectively. Between July 2002 and February 2004, 14 young male patients (aged 15-31 years) suffering from symptomatic lumbar spondylolysis were treated with TSRH hook screw fixation after direct repair of the defects. MacNab criteria were used to assess their pre-and post-operative status. Each fixation technique could significantly increase the intervertebral rotational stiffness and made the stiffness return to nearly the intact level. Hook screw technique provided more rotational stability than the others. Hook screw and Buck's techniques provided more flexion/extension stability than modified Scott's technique. Neither complication nor instrumental failure was observed in this study. The mean follow-up period was 21 months. All the patients except one acquired union during the follow-up period. Thirteen patients had a "good" or "excellent" result according to MacNab criteria. Hook screw fixation shows biomechanical advantages and is safe and effective for young patients with lumbar spondylolysis.
    Chinese Journal of Traumatology (English Edition) 11/2006; 9(5):288-92.