Objective To explore the feasibilities, methods, outcomes and indications of atlas pedicle screw system fixation and fusion for the treatment of upper cervical diseases. Methods From October 2004 to January 2006, 17 patients with upper cervical diseases were treated with atlas pedicle screw system fixation and fusion. There were 13 males and 4 females, ageing 19 to 52 years. Of 17 cases, there were 14 cases of atlantoaxial dislocation(including 3 cases of congenital odontoid disconnection,4 cases of old odontoid fracture,2 cases of new odontoid fracture(typeⅡC), 3 cases of rupture of the transverse ligament, and 2 cases of atlas fracture; 2 cases of tumor of C2; 1case of giant neurilemoma of C2,3 with instability after the resection oftumors. JOA score before operation was 8.3±3.0. Results The mean operative time and bleeding amount were 2.7 hours (2.1-3.4 hours) and 490 ml (300-750 ml) respectively. No injuries to the vertebral artery and spinal cord were observed. The medial-superior cortex of lateral mass was penetrated by 1 C1 screw approximately 3 mmwithout affecting occipito-atlantal motions. All patients were followed up 3-18 months. The clinical symptoms were improved in some extents and the screws were verified to be in a proper position, no breakage or loosening of screw and rob occurred. All patients achieved a solid bone fusion after 3-6 months. JOA score 3 months after operation was14.6±2.2. JOA improvement rates were 73%-91%(mean 82%). Conclusion The atlas pedicle screw system fixation and fusion is feasible for the treatment of upper cervical diseases and has betteroutcomes, wider indications if conducted properly.
Objective To explore the reduction and support effect of the subchondral screw compression technique for residual or secondary collapse of the lateral tibial plateau during operation. Methods Between January 2020 and June 2021, 11 patients with residual or secondary collapse of the lateral tibial plateau during operation were treated with the subchondral screw compression technique. There were 6 males and 5 females, aged 52.3 years old (range, 27-64 years). The fractures were caused by traffic accident in 10 cases and falling from height in 1 case and located at the left knee in 6 cases and the right knee in 5 cases. According to Schatzker classification, there were 5 cases of type Ⅱ fractures, 4 cases of type Ⅲ fractures, and 2 cases of type Ⅴfractures. According to the three columns classification, there were 5 cases of lateral column, 4 cases of lateral column and posterior column, and 2 cases of three columns. The time from injury to operation was 4.5 days (range, 3-7 days). During the follow-up, X-ray films were obtained and the Rasmussen standard was used to evaluate the quality of fracture reduction, meanwhile fracture healing was observed. The medial proximal tibial angle (mPTA), posterior tibial slope angle (pTSA), and articular surface collapse were measured at immediate and 12 months after operation. The knee joint range of motion was evaluated at last follow-up, and the knee joint function was evaluated using the Hospital for Special Surgery (HSS) score. Results All operations were successfully completed, with a mean operation time of 71.4 minutes (range, 55-120 minutes), and a mean hospital stay of 8.0 days (range, 5-13 days). The incisions all healed by first intention, without complications such as infection, flap necrosis, or vascular and nerve injury. All patients were followed up 16.5 months on average (range, 12-24 months). X-ray films showed that the fracture reduction score was 14-18 (mean, 16.7) according to Rasmussen score criteria; and 5 cases were rated as excellent and 6 as good. All fractures healed clinically with a mean clinical healing time of 14.9 weeks (range, 12-16 weeks), and there was no complications such as plate or screw loosening. At 12 months after operation, the mPTA and pTSA were (87.5±1.7)° and (6.2±3.1)°, respectively; there was no significant difference when compared to the values at immediate after operation [(87.6±1.8)° and (6.5±3.1)°] (P>0.05). The articular surface of the tibial plateaus was effectively supported, and it collapsed again by 0-1.0 mm at 12 months, with an average of 0.4 mm. At last follow-up, the knee joint range of motion was 115°-135° (mean, 126.8°) and the HSS score for knee joint function was 87-98 (mean, 93.9). Five patients underwent secondary operation to remove the internal fixator at 12-18 months after operation.ConclusionThe subchondral screw compression technique is helpful for the reduction of residual or secondary collapse of the lateral tibial plateau during operation, and can provide good support for osteochondral blocks.
Objective To evaluate the fixation technique of using the cervical lateral mass plate in the cervical posterior approach operation. Methods Eight patients in this group were admitted from September 2001 to November 2006. Among the 8 patients, there were 6 males and 2 females, with their ages ranging from 28 to 78 years. Cervical vertebral fracture with dislocation was found in 4 patients, C2 spinal cord injury in 1, C1 fracture in 1, cervical spinal stenosis in 1, and C2-5 spinal cord neurofibroma in 1. Muscle strength 3-4. TheFrankel grading system was usedin 6 patients with traumatic injury. Before operation, Grade C was observed in 2patients,Grade D in 3,and Grade E in 1. All the operations were performed according to requirements of the Margel’s method. We positioned 40 screws in all the patients, including 4 screws at C2,6 screws at C3,12 screws at C4,4 screws at C5,4 screws at C6,2 screws at C7,and 6 screws at T1. Results The followingup for an average of 14.1 months (range,645 months) revealed that there was no malposition of the screws in the patients. One of the 8 patients developed spinal instability in the fixed segment at 3 months after operation. The headchestbrace was applied to the patient for 3 months, and the spinal fusion was achieved. The further followingup to 45 months indicated that there was no instability occurring. The remaining patients recovered to their spinal stability by the spinal fusion. The patients also recovered in their neurological function after operation. The Frankel assessment showed that 1 patient had Grade E, 3 from Grade D to Grade E, 1 from Grade C to Grade D, and 1 from Grade C to Grade E. Conclusion The cervical lateral mass plate fixation can provide the immediate and b segmental immobilization for the good cervical spine stability.
Objective To evaluate the effectiveness of lumbopelvic fixation using the combination of closed multi-axial screws (CMAS) iliosacral fixation system and the posterior segmental spinal fixation for unstable sacral fractures. Methods Between January 2013 and November 2014, 25 patients (39 sides) with unstable sacral fractures were treated with lumbopelvic fixation using the combination of CMAS iliosacral fixation system and the posterior segmental spinal fixation. There were 17 males and 8 females, aged 19-55 years (mean, 33.9 years). The causes were traffic accident injury in 15 cases, falling injury from height in 8 cases, and crushing injury in 2 cases. The interval of injury and operation was 1-13 days (mean, 3.5 days). Fracture was classified as Denis type I in 2 sides, type II in 20 sides, and type III in 17 sides; nerve injury was rated as Gibbons grade I in 2 cases, grade II in 2 cases, grade III in 7 cases, and grade IV in 9 cases. The reduction quality was evaluated by Matta criterion, the clinical function outcome by Majeed, and nerve function by Gibbons criterion. Results The average operation time was 110 minutes (range, 80-150 minutes). The average blood loss was 570 mL (range, 250-1 400 mL). Superficial wound infection occurred in 2 patients, and was cured after debridement and antibiotic therapy. All patients were followed up for an average of 18 months (range, 15-22 months). Postoperative X-ray and CT examination showed clinical healing of sacral fractures at 8-12 weeks after operation (mean, 10 weeks). The mean removal time of internal fixation was 13 months (range, 12-20 months). No screw loosening and fracture, adhesion of internal fixation to surrounding tissue, and obvious electrolysis phenomenon occurred. According to Matta criterion, reduction was rated as excellent in 32 sides, good in 6 sides, fair in 1 side, and the excellent and good rate was 97.5%. According to Majeed functional scoring at last follow-up, the mean score was 84.7 (range, 64-98); the results were excellent in 18 cases, good in 5 cases, and fair in 2 cases, and the excellent and good rate was 92.0%. The nerve function was significantly improved when compared with preoperative one; nerve injury was rated as Gibbons grade I in 8 cases, grade II in 8 cases, grade III in 3 cases, and grade IV in 1 case. Conclusion Lumbopelvic fixation using the combination of CMAS iliosacral fixation system and the posterior segmental spinal fixation is a relatively effective fixation for unstable sacral fractures. Not only is the fracture fixation rigid for early full weight-bearing, but also nerve decompression can be performed which facilitates nerve function recovery.
Objective To compare the effectiveness of biplanar vertical fixation and inverted triangle fixation with hollow screw for Pauwels type Ⅲ femoral neck fracture in young and middle-aged patients. Methods The clinical data of 55 young and middle-aged patients with Pauwels type Ⅲ femoral neck fracture between June 2021 and December 2022 was retrospectively analyzed. All patients were treated with closed reduction and internal fixation with hollow screws, 25 cases were treated with biplanar vertical fixation (study group), 30 cases with inverted triangle fixation (control group). There was no significant difference in gender, age, affected side, cause of injury, underlying diseases, and time from injury to operation between the two groups (P>0.05). The operation time, intraoperative blood loss, fluoroscopy times, guide needle puncture times, starting time of weight bearing, time of full weight bearing, time of fracture healing, and complications were recorded and compared between the two groups. The hip joint function was evaluated by Harris score at 1 day, 6 months, 12 months after operation, and at last follow-up, and the pain relief was evaluated by visual analogue scale (VAS) score. The femoral neck shortening was measured on the X-ray film at last follow-up. Results All patients were followed up 12-31 months (mean, 22.0 months), and there was no significant difference in follow-up time between the two groups (P>0.05). The operation time, intraoperative blood loss, and fluoroscopy times in the study group were higher than those in the control group, but the difference was not significant (P>0.05). The guide needle puncture times in the study group was more than that in the control group, and the time of starting weight bearing and the time of full weight bearing in the study group were shorter than those in the control group, the differences were significant (P<0.05). Bony healing was achieved in both groups, and there was no significant difference in fracture healing time between the two groups (P>0.05). No osteonecrosis of the femoral head and incision-related complication was found in the two groups during follow-up, and the femoral neck shortening length in the study group was significantly shorter than that in the control group at last follow-up (P<0.05). There was no significant difference in Harris score between the two groups at 1 day after operation (P>0.05), and the Harris score of the study group was significantly better than that of the control group at other time points (P<0.05); there was no significant difference in VAS score between the two groups at each time point after operation (P>0.05). Conclusion Compared with the inverted triangle fixation, the treatment of Pauwels type Ⅲ femoral neck fracture with biplanar vertical fixation can effectively reduce femoral neck shortening without affecting fracture healing, and improve hip joint function in early stage.
Objective To compare the biomechanical differences among the five internal fixation modes in treatment of Day type Ⅱ crescent fracture dislocation of pelvis (CFDP), and find an internal fixation mode which was the most consistent with mechanical principles. Methods Based on the pelvic CT data of a healthy adult male volunteer, a Day type Ⅱ CFDP finite element model was established by using Mimics 17.0, ANSYS 12.0-ICEM, Abaqus 2020, and SolidWorks 2012 softwares. After verifying the validity of the finite element model by comparing the anatomical parameters with the three-dimensional reconstruction model and the mechanical validity verification, the fracture and dislocated joint of models were fixed with S1 sacroiliac screw combined with 1 LC-Ⅱ screw (S1+LC-Ⅱ group), S1 sacroiliac screw combined with 2 LC-Ⅱ screws (S1+2LC-Ⅱ group), S1 sacroiliac screw combined with 2 posterior iliac screws (S1+2PIS group), S1 and S2 sacroiliac screws combined with 1 LC-Ⅱ screw (S1+S2+LC-Ⅱ group), S2-alar-iliac (S2AI) screw combined with 1 LC-Ⅱ screw (S2AI+LC-Ⅱ group), respectively. After each internal fixation model was loaded with a force of 600 N in the standing position, the maximum displacement of the crescent fracture fragments, the maximum stress of the internal fixation (the maximum stress of the screw at the ilium fracture and the maximum stress of the screw at the sacroiliac joint), sacroiliac joint displacement, and bone stress distribution around internal fixation were observed in 5 groups. Results The finite element model in this study has been verified to be effective. After loading 600 N stress, there was a certain displacement of the crescent fracture of pelvis in each internal fixation model, among which the S1+LC-Ⅱ group was the largest, the S1+2LC-Ⅱ group and the S1+2PIS group were the smallest. The maximum stress of the internal fixation mainly concentrated at the sacroiliac joint and the fracture line of crescent fracture. The maximum stress of the screw at the sacroiliac joint was the largest in the S1+LC-Ⅱ group and the smallest in the S2AI+LC-Ⅱ group. The maximum stress of the screw at the ilium fracture was the largest in the S1+2PIS group and the smallest in the S1+2LC-Ⅱ group. The displacement of the sacroiliac joint was the largest in the S1+LC-Ⅱ group and the smallest in the S1+S2+LC-Ⅱ group. In each internal fixation model, the maximum stress around the sacroiliac screws concentrated on the contact surface between the screw and the cortical bone, the maximum stress around the screws at the iliac bone concentrated on the cancellous bone of the fracture line, and the maximum stress around the S2AI screw concentrated on the cancellous bone on the iliac side. The maximum bone stress around the screws at the sacroiliac joint was the largest in the S1+LC-Ⅱ group and the smallest in the S2AI+LC-Ⅱ group. The maximum bone stress around the screws at the ilium was the largest in the S1+2PIS group and the smallest in the S1+LC-Ⅱ group. Conclusion For the treatment of Day type Ⅱ CFDP, it is recommended to choose S1 sacroiliac screw combined with 1 LC-Ⅱ screw for internal fixation, which can achieve a firm fixation effect without increasing the number of screws.
Objective To study the application and the curative effect of compressed screw and sartorius bone flap in treating femoral neck fractures in youth or middle age. Methods From February 1996 to December 2004, 86 patients with femoral neck fracture were treated by open reduction compressed screw and sartorius bone flap, aging from 21 to 49 years. Fracture was caused by traffic accident in 35 cases, fall from height in 27 cases and fall in 24 cases. Accoding to Garden classification, 23 cases were type Ⅱ, 25 cases were type Ⅲ, and 15 cases were type Ⅳ. We analyzed fracture healing and evaluate function by observation of the postoperative X-ray films. Results Of the 86 patients, 62 were followed up 6 months to 7 years (2 years and 5 months on average). According to Weijie’s criterion for nonunion and necrosis offemoral head, nonunion occurred in 4 cases; the healing rate of fracture was 93.5%. In healed patients, necrosis of femoral head occurred in 7 cases (11.3%) after 3 years. The results of hip joint function evaluation were excellent in 44 cases, good in 8 cases, fair in 6 cases and poor in 4 cases; and the excellent and good rate was 83.9%. Conclusion Compressed screw and sartorius bone flap was simple and effective for femoral neck fractures in youth or middle age.
Objective To investigate the effectiveness of cannulated lag screws combined with lateral supporting plates in the treatment of Hoffa fracture of Letenneur type I and type III. Methods Between May 2004 and April 2011, 11 patients with Hoffa fracture of Letenneur type I and type III were treated, including 6 males and 5 females with an average age of 36 years (range, 25-47 years). Factures were caused by traffic accident in 8 cases, by falling in 2 cases, and by the other in 1 case. Fracture involved the left knee in 7 patients and the right knee in 4 patients. According Letenneur’s classification criteria, there were 7 type I fractures (6 lateral condyle fractures and 1 medial condyle fracture) and 4 type III fractures (3 lateral condyle fractures and 1 medial condyle fracture). Of 11 fractures, 9 were fresh fractures and 2 were old fractures. Two 6.5 mm cannulated lag screws combined with lateral supporting plates were used to fix fractures by anterolateral or anteromedial incision. Results All incisions achieved primary healing with no early complication. All patients were followed up 12-26 months (mean, 15 months). X-ray films showed bone healing with an average healing time of 15 weeks (range, 10-18 weeks). No loosening or breaking of internal fixator was observed; the removal time of internal fixation was 9-15 months (mean, 12 months). Accoding to Letenneur’s functional assessment system, the results were excellent in 7 cases, good in 3 cases, and poor in 1 case at last follow-up. Conclusion Cannulated lag screws combined with lateral supporting plates fixation is effective in treatment of Hoffa fracture of Letenneur type I and type III with a high union rate; anterolateral or anteromedial approach is the first choice for Hoffa fracture of type I and type III, especially for complicating by tibial plateau fracture or patella fracture.
Objective To design a new type of three-dimensional honeycomb guide for percutaneous cannulated screw placement in femoral neck fracture and evaluate its effectiveness. Methods The clinical data of 40 patients with femoral neck fracture who met the selection criteria between June 2019 and December 2020 were retrospectively analyzed. According to different intraoperative positioning methods, they were divided into control group (20 cases, free hand positioning screws) and study group (20 cases, new guide assisted positioning screws). There was no significant difference in gender, age, side, cause of injury, Garden classification, and time from injury to operation between the two groups (P>0.05). The operation time, fluoroscopy times, guide needle puncture times, and fracture healing time of the two groups were recorded. The hip function was evaluated by Harris score at last follow-up. At immediate after operation, the following imaging indexes were used to evaluate the accuracy of screw implantation distribution: screw spacing, screw coverage area, distance from screw to cervical cortex, parallelism between screws, and screw to cervical axial deviation. Results All operations were successfully completed, and the guide needle did not penetrate the femoral neck cortex. There was no significant difference in operation time and fluoroscopy times between the two groups (P>0.05); the guide needle puncture times in the study group was significantly less than that in the control group (t=8.209, P=0.000). Imaging detection at immediate after operation showed that the screw spacing and screw coverage area in the study group were significantly greater than those in the control group (P<0.05); the distance from screw to cervical cortex, parallelism between screws, and screw to cervical axial deviation were significantly smaller than those in the control group (P<0.05). All patients were followed up 7-25 months, with an average of 19.3 months. There was no significant difference in follow-up time between the two groups (t=−0.349, P=0.729). There were 2 cases of fracture nonunion in the control group and 1 case in the study group, and the other fractures completely healed. One case of osteonecrosis of the femoral head occurred in the control group. During the follow-up, there was no complication such as vascular and nerve injury, venous thrombosis, screw penetration, withdrawal, breakage, and refracture, etc. There was no significant difference in fracture healing time and Harris score at last follow-up between the two groups (P>0.05). ConclusionThe new three-dimensional honeycomb guide has the advantages of simple structure and convenient use. It can reduce the puncture times of the guide needle and effectively improve the accuracy distribution of cannulated screw implantation.
Objective To evaluate the feasibil ity and effectiveness of allograft osteochondral transplantation with arthroscopic assistance for osteochondritis dissecans (OCD) associated with large osteochondral defects. Methods From January 2004 to May 2007, 13 patients with OCD with large osteochondral defects were treated. There were 7 males and 6 females, aged 18-59 years with an average of 35.8 years. The locations were left side in 8 cases and right side in 5 cases. The disease course was 7 days to 20 years with the median duration of 42 months. Four cases had obvious sprained history. The involved locations were lateral portion of the medial femur condyle (MFC) in 5 cases, thochlea area of MFC in 2 cases and lateral femur condyle in 6 cases. The range of motion was (95.0 ± 13.5)° and the Lysholm score was 62.23 ± 7.79. According to International Cartilage Repair Society classification system and the Guhl classification of OCD under arthroscopy, all the patients were type IV. Defect areas were 3-7 cm2 with an average of 4.32 cm2. The depths of defects were 0.8-2.0 cm with an average of 1.55 cm. Allograft osteochondral transplantation combining with adsorbable screw was appl ied for the lesions. The patients were closely instructed to do exercise through following up. Results The wounds all healed by first intention Thirteen cases were followed up for 2.2 years (14 months to 4 years) after operation. Three months after operation, 2 cases had pain after continuous exercise for 1 hour, they were directed in the methods of functional exercise and to strengthen their quadriceps femoris. Medicine was given in 2 patients who had sign of friction feel ing of joint 6 months after operation. The range of motion at the last follow-up was (137.0 ± 9.8)°, showing statistically significant difference when compared with that before operation (P lt; 0.05). The X-rays and EMRI examinations at following-up indicated that bone healed well and articular facet was integrity. The Lysholm score was 92.08 ± 7.64 one year after operation, showing statistically significant difference when compared with that before operation (P lt; 0.05). Conclusion Allograft osteochondral transplantation with arthroscopic assistance is a useful method in treatment of OCD with large osteochondral defects of the knees.