OBJECTIVE: To review the anatomic character of lower cervical pedicle, the placement and the biomechanical stability of the cervical pedicle screw fixation, the clinical application and the complication caused by fixation. METHODS: The literature concerned the cervical pedicle screw fixation in recent years were extensively reviewed. RESULTS: The cervical pedicle screw fixation can be widely used in the lower cervical spine instability according to the anatomic character of lower cervical pedicle, and the good biomechanical stability of the cervical pedicle screw fixation, and the complication can be controlled. CONCLUSION: The cervical pedicle screw fixation is an effective internal fixation for the lower cervical spine instability.
【Abstract】 Objective To evaluate the method and the early effectiveness of total hip arthroplasty in the treatment of protrusio acetabuli. Methods Between January 2006 and February 2010, 16 cases (16 hips) of protrusio acetabuli were treated, including 6 males and 10 females with an average age of 56.5 years (range, 39-72 years). The median disease duration was 6.4 years (range, 1 year and 6 months to 35 years). Involved hips included 7 left hips and 9 right hips; 3 patients had primary protrusio acetabuli and 13 patients had secondary protrusio acetabuli. The preoperative Harris score was 49.5 ± 5.5. According to Dunlop et al. classification criterion, there were 3 cases of mild, 9 cases of moderate, and 4 cases of severe. All patients received total hip arthroplasty with bone graft and cementless prosthesis for recovery of femoral offset and acetabular center of rotation. Results All incisions healed by first intention without complication of infection, deep venous thrombosis, or nerve injury. All patients were followed up 12-62 months with an average of 37 months. The Harris score at last follow-up was 90.5 ± 4.5, showing significant difference (t=49.578, P=0.000) when compared with preoperative score. The X-ray films showed that no prosthesis loosening or subsidence was observed, and bone graft healed with no sign of re-protrusion. Conclusion In treatment of protrusio acetabuli, total hip arthroplasty with bone graft and cementless prosthesis can recover the femoral offset and acetabular center of rotation and provide satisfactory early effectiveness.
Objective To explore the situation of tendon-bone heal ing when allogenic tendon graft is wrapped with autologous periosteum around the tendon in rabbits. Methods Twenty healthy New Zealand white rabbits with the age of 4-5 months were used in the experiment, weighing 2.5-3.0 kg. One-side posterior l imb was selected randomly as the test, and thecontralateral l imb was served as the control at the same time. The allogenic tendon graft was designed as a tendon-bone model in the proximal tibial metaphysis of rabbits. The portion of tendon in the bone tunnel was wrapped with autologous periosteal graft in which the cambium layer was facing the bone tunnel in the experimental group, while the portion of tendon in the bone tunnel was not wrapped with autologous periosteal graft in the control group. The histologic examination of the tendon-bone interface (n=2) and the biomechanical test for maximal pullout load (n=8) were conducted 4 and 8 weeks after operation, respec tively. Results All specimens were observed with naked eyes 4 and 8 weeks after the operation. Many new bones around bone tunnel outlet were seen in the experimental group, while a few or few new bones were seen in the control group. Four weeks after operation, histological observation showed there were a lot of prol iferative mesenchymal cells in the periosteal germinal layer in the experimental group and conspicuous membrane bone formation was obvious. The arrangement of massive osteoblasts around newborn bone trabecula was similar to pal isade. The newborn bone trabecula was l inked with the periosteum. Some loose connective tissues and few newborn bones between the tendon graft and the bone tunnel were seen in the control group, and the connection of them was loose. Eight weeks after operation, the connection between the tendon graft and the bone tunnel was tight and no gap existed in the experimental group. The number of newborn bones was large and their arrangement was relatively regular. The tidemark l ine was seen between the tendon graft and the bone tunnel, which was similar to normal tendon-bone interface. The prol iferation of fibroblast was active in the periosteum, and there were many fibrous joints betweenthe periosteum and the tendon graft. Partial bone formation was seen between the tendon graft and the bone tunnel in thecontrol group, with disorderly arrangement, and there were many collagen fibrous joints between the tendon graft and the bone tunnel. Four and 8 weeks after operation, the pullout or pull and break loads of the experimental group were (35.03 ± 1.21) N/ cm and (42.36 ± 1.31) N/cm, respectively, and those of the control group were (26.14 ± 6.13) N/cm and (31.63 ± 6.87) N/ cm, respectively. There was significant difference between the two groups (P lt; 0.05). Conclusion The transplantation of autologous periosteum graft wrapping around allogenic tendon graft may shorten the time of osteochondral ossification between the tendon graft and the bone tunnel, improve heal ing strength and promote tendon-bone heal ing in the bone tunnel in rabbits.
Objective To observe the effectiveness of traumatic dislocation of the knee joint combined with multi ple ligament injuries treated by stages. Methods Between June 2005 and November 2008, 13 cases of traumatic dislocation of the knee joint combined with multi ple ligament injuries were treated by stages, including 9 males and 4 females with an average age of 30.7 years (range, 18-54 years). The dislocations were left knee in 3 cases and right knee in 10 cases. The causes of injury were sports injury in 8 cases, traffic accident injury in 2 cases, fall ing from height injury in 2 cases, and sprain injury in 1 case. The average time from injury to hospitalization was 9 hours (range, 6 hours to 2 days ). Anterior cruciate ligament (ACL), posterior cruciate ligament (PCL), and medial collateral ligament (MCL) were involved in 8 cases; ACL, PCL, and lateral collateral ligament (LCL) in 3 cases; and ACL, PCL, MCL, and LCL in 2 cases. The valgus stress testing results of 10 knees were ++ to +++; the varus stress testing results of 5 knees were ++ to +++; all knees showed positive in the anterior or the posterior drawer test and ++ to +++ in Lachman test. The nerve, vessel, MCL, LCL, PCL, meniscus were repaired in the first operation. The functional exercise of knee joint was done after fixation for 3-4 weeks. During the second operation, the ACL was reconstrcted under arthroscopy after the range of motion (ROM) of knee joint was good with anterior instabil ity of knee within 4-6 months. Results All wounds healed by first intention after two operations; no compl ications of infection and compartment syndrome occurred. All cases were followed up 12-60 months with an average of 36 months. Joint effusion of knee occurred in 2 cases at 4 weeks after the first operation and was cured after removal of fluid. At 3 months after the second operation, the results of valgus stress testing and Lachman test were ++ in 1 case, respectively; the results of valgus stress testing, varus stress testing, and Lachman test were + in 1 case, respectively; and others showed negative results. After 12 months of the second operation, the mean flexion of the knee was 123.4° (range, 100-135°), and the mean extension of the knee was 2.3° (range, 0-4°). According to Lysholm evaluation system, 9patients got excellent results, 2 good, and 2 fair; the excellent and good rate was 84.6%. Conclusion It is an effective method in the treatment of traumatic dislocation of the knee joint combined with multi ple ligament injuries by stages.
Objective To observe the cl inical results of treatment of Schatzker V/VI tibial plateau fracture involved posteromedial condyle through combined posteromedial and anterolateral approach and fixed with two or three plates. Methods From April 2005 to April 2008, 18 cases of tibial plateau fracture involved posteromedial condyle were treated, including 14 males and 4 females with an average age of 38.5 years old (range, 18-62 years old). According to Schatzker classification, there were 12 cases of type V and 6 cases of type VI. The posteromedial condyle were involved in 13 cases and bilateral posterior condyle in 5 cases. All patients were given posteromedial fragment and medial condyle fracture reduction through posteromedial approach firstly, and then lateral condyle fracture reduction through anterolateral approach, and injury of meniscuses and cruciate l igaments were treated at the same time. Three plates (lateral, medial, posterior) were used in 10 cases and two plates (lateral, posteromedial) in 8 cases. Results All wounds achieved heal ing by first intention without compl ications such as infection, flap necrosis, osteofascial compartment syndrome, chronic osteomyel itis, nonunion. All patients were followed up for 12 to 48 months with an average of 24.4 months. The mean flexion of the knee was 118.4° (range, 100-130°) 1 year after operation. According to Iowa evaluation system, 12 patients got excellent results, 4 good, and 2 fair; the excellent and good rate was 88.9%. Conclusion Combined posteromedial and anterolateral approach and fixed with two or three plates is effective in treatment of the Schatzker V/VI tibial plateau fracture involved posteromedial condyle. Anatomical reduction and rigid internal fixation of the posteromedial fragment are critical to successful operation.