Objective To investigate the appl ication of anti-rotation screw after dynamic hi p screw (DHS) in treatment of intertrochanteric fracture. Methods Between April 2006 and January 2010, 22 cases of intertrochanteric fractures underwent DHS fixation operation with an anti-rotation screw, including 15 males and 7 females with an average ageof 66.3 years (range, 54-83 years). Fractures were caused by sl ipping in 16 cases, traffic accident in 5 cases, and fall ing from height in 1 case. All cases showed closed fractures, including 13 cases in the left and 9 cases in the right. Eighteen cases were simple intertrochanteric fracture, 4 cases were intertrochanteric fractures compl icated with Colles fractures. According to Evans classification standard, there were 14 cases of type I, 6 cases of type II, 1 case of type III, and 1 case of type IV. The time from wound to operation was 3-7 days (mean, 4.5 days). Results The operation time ranged from 51-95 minutes (mean, 72 minutes). The intraoperative blood loss was 150-350 mL (mean, 270 mL). The hospital ization days were 12-35 days (mean, 16.8 days). Primary heal ing was observed in all cases. All cases were followed up 6-17 months (mean, 14 months). Union of fracture was observed at 12-16 weeks (mean, 13.6 weeks); no fracture or internal fixation loosening occurred. According to HUANG Gongyi’s standard of efficacy assessment, the results were excellent in 19 cases and good in 3 cases. Conclusion Appl ication of an anti-rotation screw can help to improve the strength of the DHS for the internal fixation of intertrochanteric fracture, especially the anti-rotation abil ity, which does not increase the operation time obviously.
To compare the effectiveness of the operations in treatment of thoracolumber spine fracture and dislocation with spinal cord injury in different periods. Methods Between June 2003 and June 2008, 80 cases of thoracolumber spine fracture and dislocation with spinal cord injury were treated. There were 52 males and 28 females with an average age of 37.6 years (range, 28-49 years). According to different operative time, they were divided into 2 groups by randomized controlled study: group A (n=39, operation was performed within 24 hours) and group B (n=41, operation was performed at 3-7 days). In group A, there were 23 cases of degree I-II (group A1), 16 cases of degree III-V (group A2) according to Meyerding standard, including 17 cases of grade A, 7 cases of grade B, 9 cases of grade C, and 6 cases of grade D according to Frankel scoring system. In group B, there were 21 cases of degree I-II (group B1) and 20 cases of degree III-V (group B2), including 20 cases of grade A, 7 cases of grade B, 11 cases of grade C, and 3 cases of grade D. All cases were treated with posterior spinal cord decompression and reduction, with internal fixation by pedicle screw-rod system and transforamen lumbar interbody fusion. Results The blood loss was (407.4 ± 24.3) mL in group A1 and (397.4 ± 8.2) mL in group B1, showing no significant difference (t=1.804, P=0.078); the blood loss was (1 046.9 ± 128.6) mL in group A2 and (494.4 ± 97.7) mL in group B2, showing significant difference (t=14.660, P=0.000). All 80 patients were followed up 2 years to 2 years and 6 months (mean, 2 years and 3 months) with satisfactory results in spinal cord decompression and reduction, and bony fusion was achieved at 12 months. There was no significant difference in the vertebral canal volume, vertebral height, and Cobb angle at both pre- and postoperation between 2 groups (P gt; 0.05). No loosening or breakage of screws and rods occurred. At 12 months after operation, the cure rates were 47.83% (11/23) in group A1 and 19.05% (4/21) in group B1, showing significant difference (χ2=4.046, P=0.044); the cure rates were 12.50% (2/16) in group A2 and 10.00% (2/20) in group B2, showing no significant difference (χ2=0.056, P=0.813). There was no significant difference (χ2=0.024, P=0.878) in the cure rates in the patients at grades A and B before operation between group A (12.50%, 3/24) and group B (11.11%, 3/27); but there was significant difference (χ2=5.992, P=0.014) in the cure rates in the patients at grades C and D before operation between group A (66.67%, 10/15) and group B (21.43%, 3/14). Conclusion Emergency operation of posterior pedicle screw-rod system for treatment of thoracolumber spine fracture and dislocation with spinal cord injury can provide good reduction, rigid fixation, and high fusion rate, so it is asafe and effective treatment method.
ObjectiveTo compare the effectiveness of posterior malleolus fractures treated by plate and screw internal fixation through posterolateral approach.MethodsThe clinical data of 95 patients with posterior malleolus fractures who were admitted between January 2016 and December 2019 and met the selection criteria were retrospectively analysed. They were divided into plate group (44 cases, treated with posterolateral plate internal fixation) and screw group (51 cases, treated with posterolateral screw internal fixation) according to different treatment methods. There was no significant difference in general data between the two groups of patients such as age, gender, cause of injury, side of injury, ankle fracture or injury classification, time from injury to operation, and percentage of posterior ankle fracture area to the distal tibia articular surface (P>0.05). The operation time, hospital stay, fracture healing time, and surgical complications were compared between the two groups. Imaging examinations (X-ray film, CT scan and reconstruction) were used to assess the reduction quality of ankle fracture, articular congruity, and re-displacement in ankle fracture. At last follow-up, the pain visual analogue scale (VAS) score was used to evaluate the patients’ pain, and the American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot score was used to evaluate ankle joint function.ResultsPatients in both groups were followed up 6-30 months, with an average of 18.2 months. The operation time of the plate group was significantly longer than that of the screw group (U=?2.040, P=0.041); there was no significant difference in hospital stay between the two groups (U=?1.068, P=0.285). Incision swelling occurred in 2 cases in the plate group, sural nerve injury in 3 cases, and traumatic arthritis in 2 cases during follow-up. In the screw group, there were 1, 2, and 2 cases, respectively. The incidence of complications in the two groups (15.9% vs. 9.8%) was not significantly different (P=0.372). All patients who underwent tibiofibular screw fixation underwent the removal of the tibiofibular screw before taking full weight bearing at 12 weeks after operation, and there was no screw fracture and retention. During the follow-up, there was no infection, re-displacement of fracture, delayed bone union or nonunion, and there was no significant difference in fracture healing time between the two groups (t=0.345, P=0.731). There was no significant difference between the two groups of reduction quality of ankle fracture and articular congruity evaluation results (P>0.05). At last follow-up, there was no significant difference in VAS score, AOFAS ankle-hindfoot score and evaluation grade between the two groups (P>0.05).ConclusionBoth the plate and screw internal fixation through posterolateral approach can achieve satisfied effectiveness in the treatment of posterior ankle fractures with maintenance of fracture reduction, and recovery of ankle joint function. The screw internal fixation has the advantages of minimal invasion and shorter operation time.
ObjectiveTo explore the effectiveness of arthroscopic treatment of scaphoid fracture nonunion with bone graft and Kirschner wire combined with screw fixation. MethodsThe clinical data of 14 patients with scaphoid fracture nonunion who met the selection criteria between February 2021 and September 2022 were retrospectively analyzed. There were 13 males and 1 female with an average age of 32 years ranging from 17 to 54 years. The time from injury to operation ranged from 6 to 15 months, with an average of 9.6 months. According to the Slade-Geissler classification of scaphoid fracture nonunion, there were 3 cases of grade Ⅲ, 8 cases of grade Ⅳ, and 3 cases of grade Ⅴ. The preoperative visual analogue scale (VAS) score was 5.9±1.0, and the modified Mayo wrist score was 53.2±9.1. There were 2 cases of scaphoid nonunion advanced collapse, both of which were stage Ⅰ. All patients were treated with arthroscopic bone graft and Kirschner wire combined with screw fixation, and the fracture healing was observed by X-ray film monthly after operation, and the effectiveness was evaluated by VAS score and modified Mayo wrist score before and after operation. ResultsAll patients were followed up 6-14 months, with an average of 8.4 months. All fractures healed in 4-8 months, with an average of 6.3 months. The postoperative pain symptoms and wrist function of the patients significantly improved when compared with those before operation, and the VAS score at last follow-up was 2.4±1.3, and the modified Mayo wrist score was 87.1±6.7, which were significantly different from those before operation (t=12.851, P<0.001; t=?14.410, P<0.001). According to the modified Mayo wrist evaluation, 9 cases were excellent, 3 cases were good, and 2 cases were fair. Conclusion Arthroscopic bone graft and Kirschner wire combined with screw fixation is an effective surgical method for the treatment of scaphoid fracture nonunion.
ObjectiveTo investigate the effectiveness of spring hook plate for posterior malleolus fracture by comparing with cannulated screw. MethodsBetween March 2012 and September 2013, 100 cases of posterior malleolus fracture were treated. Fracture was fixed with spring hook plate in 50 cases (research group) or with cannulated screw in 50 cases (control group). There was no significant difference in gender, age, cause of injury, associated injury, and injury to operation time between 2 groups P>0.05). The operation time, intraoperative blood loss, union time of fracture, ankle range of motion (ROM), and complications were recorded and compared. The ankle joint function was evaluated by the ankle hindfoot scale of American Orthopedic Foot and Ankle Society (AOFAS). ResultsThere was no significant difference in operation time and intraoperative blood loss between 2 groups P>0.05). The patients were followed up 6-12 months (mean, 9.8 months) in the control group and 6-12 months (mean, 9.2 months) in the research group. The X-ray films showed that fracture union was achieved in 2 groups; the union time of the research group[(9.5±1.4) weeks] was significantly shorter than that of the control group[(10.5±1.3) weeks] (t=2.029, P=0.017). The ROM was (25.1±3.2)° for dorsal extension and was (45.3±2.3)° for plantar flexion in the research group at 6 months after operation, which were significantly better than those of the control group[(22.2±2.3)° and (41.2±2.5)°] (t=-3.950, P=0.001; t=-5.212, P=0.000). The ankle hindfoot scale of AOFAS was 85.1±8.6 in the control group at 6 months; the results were excellent in 15 cases, good in 20 cases, and moderate in 15 cases with an excellent and good rate of 70%. The ankle hindfoot scale of AOFAS was 89.4±7.9 in the research group; the results were excellent in 20 cases, good in 22 cases, and moderate in 8 cases with an excellent and good rate of 84%; there was significant difference between 2 groups (t=-2.191, P=0.042; χ2=0.413, P=0.018). Incision infection occurred in 3 cases of the control group and in 2 cases of the research group, which was cured after dressing change; screw loosening and fracture displacement occurred in 3 and 4 cases of the control group, but did not in the research group. The complication rate of the control group and the research group was 20% and 4% respectively, showing significant difference between 2 groups (χ2=6.061, P=0.028). ConclusionSpring hook plate can shorten the time of union, increase the ROM of the ankle after operation, get good functional restoration, and decrease the rate of complication compared with cannulated screw fixation.
ObjectiveTo investigate the effectiveness of debridement and single-incision vertebral screw-rod fixation combined with pedicle screw-rod fixation and autograft bone fusion in treatment of thoracolumbar tuberculosis. MethodsBetween January 2008 and October 2010, 22 patients with thoracolumbar tuberculosis were treated by debridement and single-incision vertebral screw-rod fixation combined with pedicle screw-rod fixation and autograft bone fusion, and were given anti-tuberculosis therapy after operation. Of 22 patients, 14 were male and 8 were female with an average age of 42 years (range, 18-66 years). The disease duration was 2-16 months (mean, 6 months). Sixteen double-segment lesions included T7, 8 in 3 cases, T8, 9 in 1 case, T9, 10 in 3 cases, T11, 12 in 2 cases, L1, 2 in 4 cases, and L3, 4 in 3 cases; 6 three-segment lesions included T7-9 in 2 cases, T11-L1 in 1 case, and L2-4 in 3 cases. Preoperative visual analogue scale (VAS) score was 7.50 ± 0.63. According to Frankel classification of America Spinal Injury Association (ASIA), 2 cases were rated as grade B, 4 cases as grade C, 9 cases as grade D, and 7 cases as grade E. ResultsTwenty-two patients were followed up 15-36 months (mean, 25.2 months). Wound infection occurred in 1 case and was cured after corresponding treatment; incision healed by first intention in other patients. No loosening or breakage of internal fixator was found; the patients had no deteriorations in spinal cord injury or cerebrospinal fluid leakage. X-ray films and CT showed obvious bone fusion in the intervertebral space. The time of bone fusion was 3-6 months (mean, 5.2 months). The erythrocyte sedimentation rate after operation was significantly lower than that before operation (P lt; 0.05). The VAS scores were significantly improved to 2.90 ± 1.00 at 2 weeks after operation and 2.60 ± 0.81 at last follow-up (P lt; 0.05). At last follow-up, nerve function was significantly improved. According to Frankel classification, 2 cases were rated as grade C, 5 cases as grade D, and 15 cases as grade E. ConclusionSingle-incision vertebral screw-rod fixation combined with pedicle screw-rod fixation for thoracolumbar tuberculosis is a stable and minimally invasive method. However, the long-term effectiveness need further follow-up.
ObjectiveTo investigate the stability of unilateral fractured vertebral pedicle screw fixation in the treatment of thoracolumbar fracture. MethodsEighteen fresh calf thoracolumbar spine specimens (T11-L3) were obtained to establish the L1 burst fracture models with Panjabi's high speed trauma apparatus, and were divided into 3 groups:pedicle fixation for adjacent upper and lower vertebrae of fractured vertebra (4 pedicle screws in group A), combined with pedicle screw fixation for unilateral fractured vertebrae (5 pedicle screws in group B), and three-level 6 pedicle fixation (group C). Under normal, fractured, and reconstructed conditions, the range of motion (ROM) of adjacent upper and lower vertebrae of fractured vertebra were measured in flexion, extension, bilateral bending, and axial rotation. Axial stiffness under flexion-compression was measured on the MTS-858 testing system. ResultsThere was no significant difference in ROM and axial stiffness under normal and fractured conditions in all directions among groups (P<0.05), indicating load balance in the groups. ROM of groups B and C were significantly less than that of group A under reconstructed condition in all directions (P<0.05), but no significant difference was found between group B and group C (P>0.05). Biomechanical test showed that group B was significantly higher than group A in the axial stiffness value (P<0.05), but difference was not significant between group B and group C (P>0.05). ConclusionTranspedicular fixation of fractured vertebrae can enhance the stability of the spine. Both unilateral and bilateral fractured vertebral pedicle screw fixations have the same stability.
【Abstract】 Objective To evaluate the effectiveness of percutaneous fixation of pelvic fracture by Acutrak full thread headless hollow compression screw. Methods Between March 2008 and April 2010, 31 patients with pelvic fracture underwent percutaneous fixation surgery with Acutrak full thread headless hollow compression screw (surgical group). The effectivenss was compared with those of 14 patients with pelvic fracture treated conservatively (control group). There was no significant difference in age and sex between 2 groups (P gt; 0.05). The injury was more severe in surgical group than in control group. The standard of short-term recovery was active turning over and walking for 5 steps with walking aids. The standard of long-term recovery was pain, gait, fracture healing, and function recovery. Results In surgical group, the other patients reached the standard of short-term recovery at 1-4 days after injury except 1 patient who had sacral plexus injury; in control group, the patients could turn over at 9-13 days (Tile type A2) and 17-25 days (Tile type B2) respectively, and could walk at 17-21 days (Tile type A2) and at 45-57 days (Tile type B2) respectively. The patients of 2 groups were followed up 6-19 months. The time of fracture healing was 2-6 months. The long-term results were excellent in 29 cases and good in 2 cases in surgical group, and were excellent in 8 cases and good in 6 cases in control group, showing significant difference between 2 groups (χ2=6.636, P=0.017).Conclusion Percutaneous internal fixation combined with Acutrak full thread headless hollow compression screw can provide more effective treatment. It can alleviate patients, pain quickly, improve life quality, and has better long-term effectiveness.
Objective To biomechanically compare the maximum pull-out strengths among two pedicle screws and three salvage techniques using poly methylmethacrylate (PMMA) augmentation in osteoporotic sacrum, and to determine which PMMA augmentation technique could serve as the salvage fixation for loosening sacral pedicle screws. Methods Eleven sacra were harvested from fresh adult donated cadavers, aged from 66 to 83 years (average 74.4 years) and included 5 men and 6 women. Radiography was used to exclude sacra that showed tumor or inflammatory or any other anatomic abnormal ities. Following the measurement of bone mineral density, five sacral screw fixations were sequentially establ ished on the same sacrum as follows: unicortical pedicle screw (group A), bicortical pedicle screw (group B), unicortical pedicle screw with the traditional PMMA augmentation (group C), ala screw with the traditional PMMA augmentation (group D), and ala screw with a kyphoplasty-assisted PMMA augmentation technique (group E). According to the sequence above, the axial pull-out test of each screw was conducted on a MTS-858 material testing machine. The maximum pull-out forces were measured and compared. The morphologies of PMMA augmented screws after being pulled-out were also inspected. Results The average bone mineral density of 11 osteoporotic specimens was (0.71 ± 0.08) g/cm2 . By observation of the pull-out screws, groups C, D, E showed perfect bonding with PMMA, and group E bonded more PMMA than groups C and D. The maximum pull-out forces of groups A, B, C, D, and E were (508 ± 128), (685 ± 126), (846 ± 230), (543 ± 121), and (702 ± 144) N, respectively. The maximum pull-out strength was significantly higher in groups B, C, and E than in groups A and D (P lt; 0.05), and in group C than in groups B and E (P lt; 0.05). There was no significant difference in pull-out strength between groups A and D, and between groups B and E (P gt; 0.05). Conclusion For sacral screw fixation of osteoporotic patients with bone mineral density more than 0.7 g/cm2, bicortical pedicle screw could acquire significantly higher fixation strength than the unicortical. Once the loosening of pedicle screw occurs, the traditional PMMA augmentation or ala screw with kyphoplasty-assisted PMMA augmentation may serve as a suitable salvage technique.
Objective To compare the biomechanical properties of the anterior transpedicular screw-artificial vertebral body (AVB) and conventional anterior screw plate system (AP) in lower cervical spine by finite element study. Methods CT images (C1-T1) were obtained from a 38-year-old female volunteer. The models of intact C3-7 (intact group), AP fixation (AP group), and AVB fixation (AVB group) were established and analyzed by Mimics 14.0, Geomagic Studio 2013, and ANSYS 14.0 softwares. The axial force of 74 N and moment couple of 1 N·m were loaded on the upper surface and upper facet joint surfaces of C3. Under conditions of flexion, extension, lateral bending, and rotation, the Von Mises stress distribution regularity and maximum equivalent stree of AP and AVB groups were recorded, and the range of motion (ROM) was also analyzed of 3 groups. Results The intact model of lower cervical spine (C3-7) was established, consisting of 286 382 elements and 414 522 nodes, and it was successfully validated with the previously reported cadaveric experimental data of Panjabi and Kallemeyn. The stress concentrated on the connection between plate and screw in AP group, while it distributed evenly in AVB group. Between AP and AVB groups, there was significant difference in maximum equivalent stress values under conditions of 74 N axial force, flexion, extension, and rotation. AVB group had smaller ROM of fixed segments and larger ROM of adjacent segments than AP group. Compared with intact group, whole ROM of the lower cervical spine decreased about 3°, but ROM of C3, 4 and C6, 7 segments increased nearly 5° in both AP and AVB groups. Conclusion As a new reconstruction method of lower cervical spine, AVB fixation provides better stability and lower risk of failure than AP fixation.