Objective To evaluate the clinical effect of cannulatedscrew on treatment of femoral neck fracture(FNF). Methods Forty-two FNFpatients were treated by using cannulated screw from January 2001 to December 2005.There were 22males and 20 females with an average age of 41 years (19-59 years). Fracture was caused by traffic accident in 21 cases, by falling from height in 14 cases and by bruise in 7 cases. All cases were fresh fracture. According to Garden criterion for typing, 15 cases were classified as type Ⅱ, 16 cases as type Ⅲ and 11 cases as type Ⅳ . It was 7 hours to 15 days from injury to operation. Results Thepatients were followed up for 1-6 years with an average of 2.5 years. The average fracture union time was 6.5 months. Three patients had ischemic necrosis of femoral head, andloosening and breakage of screw and rob was observed in 1 case. According to Brumback criterion for hip joint function, the result was excellent in 18 cases, good in 20 cases and bad in 4 cases, and the excellent and good rate was 90.4%. Conclusion Cannulated screw fixation is a good method to treat FNF in young adults. It can improve the rate of fracture union and reduce the rate of avascular necrosis of femoral head.
Objective To retrospectively analyze the effectiveness of percutaneous anterior odontoid and transarticular screw fixation for type II odontoid fracture treated in the elderly patients. Methods Between October 2009 and March 2012, 5 patients with odontoid fracture were treated with anterior triple screws fixation. There were 4 males and 1 female with an average age of 69.4 years (range, 65-74 years). Fracture was caused by falling injury from height in all cases. The average time between injury and operation was 6.8 days (range, 3-12 days). According to Anderson-D’Alonzo classification system, all 5 cases were classified as type II odontoid fractures; 1 case accompanied by anterior arch fracture. Four cases were rated as grade E and 1 case as grade D on the basis of Frankel classification system on nerve function evaluation. Percutaneous anterior odontoid and transarticular screw fixation were used in all cases. The operation time, intra-operative blood loss, X-ray exposure time, and complications were recorded. The X-ray films were taken to observe atlantoaxial stability and implant conditions. Results All patients were successfully complete the surgery, and no open operation was needed. The average operation time was 103.6 minutes (range, 93-114 minutes). The average intra-operative blood loss was 5.6 mL (range, 3-10 mL). The average X-ray exposure time was 24.2 seconds (range, 17-32 seconds). Good reduction of atlantoaxial joint and primary healing of incision were obtained in 5 patients. The average follow-up duration was 21.4 months (range, 12-35 months). Transient dysphagia occurred in 3 cases, and was cured after 5 days of expectant treatment. No major complications of carotid artery laceration, spinal cord injury, esophageal perforation, airway obstruction, and implant failure occurred. The X-ray films showed odontoid bony union, atlantoaxial stability and good position of screws. The average time of odontoid fracture union was 7 months (range, 5-10 months). Five patients had normal neurological function (Frankel grade E) at last follow-up. Three patients complained of neck discomfort and movement limitation and had normal daily activities without special therapy; the other 2 patients had no clinical symptom of discomfort. Conclusion Percutaneous anterior odontoid and transarticular screw fixation is a safe and effective procedure for treatment of type II odontoid fractures in the elderly patients with minimally invasive surgical advantages.
Objective To explore an effective way fortreating severe complicated distal femoral fractures. Methods Twenty-six patients with complicated distal femoral fracture who all belonged to 33C3.3type according to AO/ASIF lassification, were treated with a lateral condylar buttress plate or self-desinged aliform anatomical plate, and operated on with allogeneic bone grafting. Results All cases were followed up for an average of 14 months (ranging 5-25 months). Twenty-four wounds were primary healing postoperatively, 2 wounds were infected and healed after dressing change. Twenty-four had bone healing after 411 months, 2 needed to operate again because of earlier weight-bearing resulting in fixation failure. According to shelbourne and Brueckmann score, the excellent and good rate was 88.46%. Conclusion The internal fixation forcomplicated distal femoral fracture by self-designed aliform anatomical plate and lateral condylar buttress plate with a great deal of allograft bone is an effective surgical method. As it has long oval holes and the holes are consecutive ,the aliform anatomical plate is more suitable for severe complicated fractures. At the same time, autogenous-ilium transplantation can be substituted by the allograft bone.
Objective To investigate the cl inical appl icabil ity and value of internal fixator for the reconstruction of lumbar isthmus in the treatment of lumbar vertebral spondylolysis and to lay a fundation for its cl inical appl ication. Methods Sixteen healthy goats weighing 22.65-31.22 kg were selected to establ ish the models of vertebral spondylolysis at L5, which thereafter were randomized into two groups (n=8): bone graft group in which 0.8-1.1 g fresh autogenous bone was transplanted into the isthmus spondylolysis area, and internal fixation with bone graft group in which internal fixator was installed before transplanting 0.8-1.1 g fresh autogenous bone into the isthmus spondylolysis area. All animals were killed 8 weeks after operation to receive imaging, topographic anatomy and histology detection. Meanwhile, biomechanics test was performed by using 5 donated vertebral body specimens (4 males and 1 female aged 35-51 years old). The left isthmus of L5 vertebra was transected to serve as lumbar vertebral spondylolysis model. A mini-displacement sensor was put at the transected ends of the isthmus. Then loading was conducted with a constant velocity of 2 mm/min by electronic omnipotent tester simulating the direction of fixation force of the internal fixator, and the deformation value of the transected ends was collected by a dynamic data collector and analyzer. The loading wascontinued until the vertebra specimens were damaged. The deformation of displacement sensor and the closure of transected ends of the lumbar isthmus were observed. Results All the goats behaved normally shortly after operation, and no nerve injury induced by operation and no wound infection occurred. Bilaterally obl ique X-ray films of lumbar vertebra and topographic anatomy 8 weeks after operation showed the fusion rate of the internal fixation and bone graft group and the bone graft group was 100% and 62.5%, respectively, indicating there was a significant difference (P lt; 0.05). Histology observation showed 3 goats in the bone graft group presented empty bone trabecula, empty bone lacuna and the disappearance of osteocytes at the transected ends of lumbar isthmus; while in the internal fixation and bone graft group, the bone trabecula grew into cancellous structures with hematopoietic and fatty bone marrow tissue inside, and parts of the bone trabecula had various degrees of mosaic-l ike pattern. During the upload, the biomechanics test and data processing results showed when the external load was 40 N, the deformation of displacement sensor was identified and the gap between the transected ends of lumbar isthmus started to close; then with the increase of external load, the displacement sensor tended to ascend in a l inearity manner; while when the external load was 212 N, the displacement sensor had no further deformation, the gap between the transected ends of lumbar isthmus wascompletely closed, and the pressor effect appeared. Conclusion The internal fixator for the reconstruction of lumbar isthmus has mechanical effects of stabil izing and elevating pressure with a high fusion rate.
Objective To compare the biomechanical differences among the three novel internal fixation modes in treatment of bicondylar four-quadrant fractures of the tibial plateau through finite-element technique, and find an internal fixation modes which was the most consistent with mechanical principles. Methods Based on the CT image data of the tibial plateau of a healthy male volunteer, a bicondylar four-quadrant fracture model of the tibial plateau and three experimental internal fixation modes were established by using finite element analysis software. The anterolateral tibial plateaus of groups A, B, and C were fixed with inverted L-shaped anatomic locking plates. In group A, the anteromedial and posteromedial plateaus were longitudinally fixed with reconstruction plates, and the posterolateral plateau was obliquely fixed with reconstruction plate. In groups B and C, the medial proximal tibia was fixed with T-shaped plate, and the posteromedial plateau was longitudinally fixed with the reconstruction plate or posterolateral plateau was obliquely fixed with the reconstruction plate, respectively. An axial load of 1 200 N was applied to the tibial plateau (a simulation of a 60 kg adult walking with physiological gait), and the maximum displacement of fracture and maximum Von-Mises stress of the tibia, implants, and fracture line were calculated in 3 groups. Results Finite element analysis showed that the stress concentration area of tibia in each group was distributed at the intersection between the fracture line and screw thread, and the stress concentration area of the implant was distributed at the joint of screws and the fracture fragments. When axial load of 1 200 N was applied, the maximum displacement of fracture fragments in the 3 groups was similar, and group A had the largest displacement (0.74 mm) and group B had the smallest displacement (0.65 mm). The maximum Von-Mises stress of implant in group C was the smallest (95.49 MPa), while that in group B was the largest (177.96 MPa). The maximum Von-Mises stress of tibia in group C was the smallest (43.35 MPa), and that in group B was the largest (120.50 MPa). The maximum Von-Mises stress of fracture line in group A was the smallest (42.60 MPa), and that in group B was the largest (120.50 MPa). Conclusion For the bicondylar four-quadrant fracture of the tibial plateau, a T-shaped plate fixed in medial tibial plateau has a stronger supporting effect than the use of two reconstruction plates fixed in the anteromedial and posteromedial plateaus, which should be served as the main plate. The reconstruction plate, which plays an auxiliary role, is easier to achieve anti-glide effect when it is longitudinally fixed in posteromedial plateau than obliquely fixed in posterolateral plateau, which contributes to the establishment of a more stable biomechanical structure.
Objective To investigate the short-term effectiveness of reconstruction plate internal fixation via improved Stoppa approach combined with iliac fossa approach and Kocher-Langenbeck approach for complex acetabular fractures. Methods Between January 2015 and January 2020, 30 patients with complex acetabular fractures were treated with reconstruction plate internal fixation via improved Stoppa approach combined with iliac fossa approach and Kocher-Langenbeck approach. There were 20 males and 10 females with an average age of 52.1 years (range, 25-71 years). The cause of injury included traffic accident in 17 cases and falling from height in 13 cases. Among them, 14 cases were left acetabular fractures and 16 cases were right acetabular fractures. According to Letournel classification, there were 16 cases of double column fractures, 2 cases of transverse fracture with posterior wall fracture, 4 cases of anterior column and posterior hemi-transverse fractures, 8 cases of T-shaped fracture. The displacement distance of fracture ranged from 6 to 30 mm (mean, 11.6 mm). The time from injury to operation was 6-14 days (mean, 8.7 days). Results The operation time was 2.0-4.5 hours (mean, 3.0 hours). The intraoperative blood loss was 200-800 mL (mean, 450.0 mL). All patients were treated with autologous blood transfusion during operation. All incisions healed by first intention after operation, and no infection occurred. All patients were followed up 12-15 months (mean, 13.4 months). The drainage tube was removed at 2-3 days after operation. After extubation, X-ray film and three-dimensional CT were performed to recheck the fracture reduction. According to Matta score system, 20 cases were excellent, 5 were good, and 5 were poor, the excellent and good rate was 83.3%. All fractures healed with the healing time of 16-25 weeks (mean, 17.7 weeks). According to Merle d’Aubigne-Postel score system, the hip function at 1 year after operation was rated as excellent in 18 cases, good in 6 cases, and fair in 6 cases, and the excellent and good rate was 80.0%. Two cases suffered from sciatic nerve injury due to traction during operation, 7 cases had heterotopic ossification, 2 cases had traumatic hip arthritis, and no other complications occurred. Conclusion For complex acetabular fractures, the reconstruction plate internal fixation via improved Stoppa approach combined with iliac fossa approach and Kocher-Langenbeck approach can obtain good short-term effectiveness with good reduction and hip joint function, and less complications.
Objective To study the cl inical effect of expert tibial nail (ETN) in the treatment of the complex tibial fractures of type C. Methods From May to October 2008, 10 cases of complex tibial fractures of type C were treated with unreamed ETN and closed reduction. There were 7 males and 3 females aging from 23 to 50 years with an average age of 39 years. Fracture was caused by traffic accident in 6 cases, by crush in 2 cases, and by fall ing from height in 2 cases. According to Association for the Study of Internal Fixation (AO/ASIF) classification, there were 2 cases of 42-C1 fractures, 4 cases of42-C2 fractures, and 4 cases of 42-C3 fractures; including 4 cases of closed fractures and 6 cases of open fractures (2 cases of Gustilo type I and 4 cases of Gustilo type II). Results The mean duration of surgery and blood loss were 75 minutes (range, 60-110 minutes) and 55 mL (range, 20-100 mL), respectively. All the incision healed by first intension without compl ication of infection. All cases were followed up for 12-17 months (average 14 months). X-ray films showed that no breakage of nail, iatrogenic fracture, l imb shortening, and angulation deformity occurred. All fractures healed after 3-8 months (average 4.2 months). At last follow-up according to Johner-Wruhs standard for the functional recovery, the results were excellent in 8 cases and good in 2 cases. Conclusion ETN has an angular stable locking system for intramedullary nails, which can enhance axial and transverse stabil ity for the treatment of complex tibial fractures of type C. It will provide firm fixation and minimal invasion.
Objective To explore the biomechanical stabil ity of ideal compression screw (I.CO.S.) for treatment of femoral neck fracture and to provide theoretical basis for choosing I.CO.S. in cl inical appl ication. Methods Thirty cadaveric human femurs were selected and divided randomly into experimental group (n=15) and control group (n=15), 15 in each group were divided equally into three sub-groups (n=5) again. The model of subcapital femoral neck fracture was made, then given anatomical reduction and fixed with I.CO.S. (experimental group) and general cannulated compression screw (control group) separately with three different configurations: two horizontal (parallel screws in superior aspect of femoral neck), two vertical (parallel screws in sagittal plane of femoral neck) and reverse triangle. The different biomechanical performances were evaluated through experimental stress analysis. Results In biomechanical stabil ity aspect: groups A, B, C was better than groups D, E, F in respect of horizontal displacement and yield load (P lt; 0.05); groups A, D was better than groups B, E in respect of the straining, horizontal displacement and yield load (P lt; 0.05); and there were not significant differences in all biomechanical indicators between group C and group F, and between group A and group C(P gt; 0.05). Conclusion I.CO.S. has the good biomechanical stabil ity for treatment of femoral neck fracture, which mayprovide basis for appl ication.