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Objective To design a new method of posterior wall reconstruction for severely corn-minuted and obsolete fracture of the posterior wall of the aeetabulum. Methods (1) Biomechanical study (from two perspectives: the stability and the stress distribution on the femoral head and the acetabu-lure) : six fresh adult' s pelvis and femur specimens were collected and divided into experimental group ( consisted of the left sides) and control group ( consisted of the right sides). After the defects of the pos-terior wall were made, the defects were anatomically reconstructed with the harvested ilium by acetabular tridimentional memory fixation system (ATMFS) in the experimental group, whereas the acetabular frag-ments were repositioned to the defect sites and fixated by the plates and screws in the control group. Lon-gitudinal and latitudinal displacement, stability of the anatomically reconstructed posterior wall of the ace-tabulum, the fitness of femoral head to the acetabulum after anatomical reconstruction and mean and maxi-mum pressure of anterior wall, posterior and cupuh of the acetabuhm were analysed and compared. (2) Cinical study: The posterior wall defect on the harvested ilium piece was repaired with 3-directional loc-king of ATMFS in 10 male patients (at age of 16-50 years, mean 36.4 years) from January 2000 to June 2002. There were seven patients with flesh acetabular fractures and three with old acetabular fractures.The period from fracture to reconstruction for the patients with old fractures was 58-251 days ( 137.7 days an average). The patients were foUowed up for 5.8 years (average 5.2-7.1 years). Results (1) Biomechanical study showed no statistical difference upon stability and fitness of femoral head to acetabu-lum after reconstruction in experimental and control groups. (2) Clinical study: postoperative X-ray film showed no repeated displacement of the fracture and the patients began out-of-bed movement with weight bearing after 1.6 months (1.2-2.1 months). Heterotopic ossification was found in two patients, with no influence on the joint function. According to the elinieal ranking standard of Modified d' Aubigne and Postal, the excellence rate was 93%. Conclusions Anatomical reconstruction of posterior wall of the acetabulum by using serf ilium with ATMS has good stability and stress distribution of the femoral head and the reconstructed acetabulum in clinical application and offers a new method for treatment of severely comminuted and obsolete fracture of posterior wall of acetabulum.
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OBJECTIVE: To compare the clinical effect between Gamma nail and proximal femoral nail (PFN) on the treatment for femoral intertrochanteric fractures in the elderly.METHODS: A total of 131 cases (39 males and 92 females; aged 70?81 years, mean age of 76 years) with femoral intertrochanteric fractures were collected from the Department of Orthopaedics, the Affiliated Changhai Hospital of the Second Military Medical University of Chinese PLA from January 2005 to January 2008. Femoral intertrochanteric fractures were classified based on AO system, including type A1 (n=56) and type A2 (n=75). All cases were randomly divided into Gamma nail group (n=65) and PFN group (n=66). Pre- and post-operative blood loss, blood transfusion volume, operating time, and length of stay were recorded, while the complications were detected following nail implantation. Functional changes of injured limbs were detected after 9 months.RESULTS: At 9 months after following up, there was no significant difference in blood loss, blood transfusion volume, operating time, and length of stay between the two groups before and after implantation (P> 0.05). Furthermore, complications did not occur during or after implantation. Six cases in the PFN group had infection in which of them had diabetes mellitus. There were no complications such as cutting out of femoral head, femoral shaft fractures, breakage of internal device or pushing out phenomenon. All cases got bone union at the final follow-up of nine months and did not get nonunion, delayed union of fractures or shortening of injured extremity.CONCLUSION: Gamma nail and PFN have equal effect on the treatment of femoral intertrochanteric fractures in the elderly.
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BACKGROUND:Swan-like memory connector (SMC) can form a three-dimensional fixation on long bone shaft,ensure the stability of fracture ends,and produce a continuous dynamic compressive stress on the fracture ends.Insulin-like growth factorⅠ (IGF-Ⅰ) regulates bone development and metabolism,cell differentiation,as well as mitosis.During the union process of fracture,IGF-I is effective to promote cellular proliferation,stimulate bone formation and result in chondrogenesis.OBJECTIVE:To quantitatively determine the effect of SMC and conventional dynamic compression plate (DCP) on the concentration of local IGF-Ⅰ in the union duration of rabbit humerus fracture.DESIGN,TIME AND SETTING:A controlled observational animal study was performed in the laboratory,Department of Orthopaedics,Changhai Hospital,the Second Military Medical University of Chinese PLA from January to May in 2007.MATERIALS:SMC was Ni-Ti alloy panel,comprising 50%-53% Ni,was customized by Lanzhou Seemine Shape Memory Alloy Co.,Ltd.The temperature of shape recovery was (33±2) ℃.METHODS:Thirty adult New Zealand rabbits were used in this study and were processed into osteotomy.The experiment sides of rabbit humerus were cut and fixed with SMC at random,serving as SMC group,and the other sides were cut at the same position and fixed with DCP,serving as DCP group.Each five animals were put to death at the time points of 2,3,4,6,8,and 12 weeks after internal fixation.Specimens were obtained from the areas that were 0.5 cm besides the fracture line.MAIN OUTCOME MEASURES:Following internal fixation,the contents of local IGF-Ⅰ in the specimens of different time points (2,3,4,6,8,and 12 weeks) were determined in both SMC group and DCP group.RESULTS:In the SMC-treated group,the contents of IGF-I increased 2 weeks after internal fixation,reached the maximum at 6 weeks,and then decreased at 8-12 weeks.In the DCP-treated group,the contents of IGF-Ⅰincreased 2 weeks after internal fixation,reached the maximum at 8 weeks,and then decreased at 12 weeks.No significant differences were found between the SMC group and the DCP group at 2,8,12 weeks after internal fixation (P ＞ 0.05).Compared with the DCP group,the SMC group had a remarkably higher content of IGF-Ⅰ at the time points of 3,4 and 6 weeks (P ＜ 0.05).The difference was the most statistically significant at 4 weeks.CONCLUSION:Compared with conventional DCP,the SMC could better promote the secretion of IGF-Ⅰin fracture and facilitate the fracture union due to the continuous dynamic compressive stress and three-dimensional fixation.
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Objective To discuss the therapy for acetabular comminuted fractur e combined with compressive defects. Methods From July 1997 to February 2005, 43 cases of comminuted acetabular fracture combined with compressive defect were t reated. 25 cases were obsolete, 16 fresh, and 2 malformed (90 days after injury) . 34 cases were complicated fractures with defects, and 9 simple fractures with defects. The defect volumes ranged from 3 to 9 cm3, averaging 4.5 cm3. They were treated with ATMFS (acetabular tridimensional memory fixation system) to fixate the comminuted bone fragments tridimensionally. The modified acetabular approac h, reduction of acetabular comminuted articular face, anatomical reconstruction of posterior wall of acetabulum with autogenous ilium, autogenous and artificial bone implantation and bone wax isolation were used. The follow-ups lasted from 5 to 86 months, averaging 15.7 months. Results 31 cases achieved anatomical red uction by filling up the compressive defects. 12 cases were treated by anatomica l reconstruction of posterior wall. On average, 5.3 months after operation, the injured hip joint was as good as the healthy one in 40 cases. Ischemia necrosis of femoral head occurred in 1 case, and 2 cases experienced heterotopic ossifica tion with ischemia necrosis of femoral head which led to osseous fusion of hip j oint. Conclusion The new methods for treatment of acetabular fractures with comp ressive defects elevate the reduction rate of acetabulum and femoral head, and a re effective for the functional recovery of hip joint.
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Objective To research on the new technique and method of bone grafting for nonunion of four limbs. Methods A new method of bone grafting was developed to take advantage of Nitinol Shape Memory Connector. It included splinting mode, padding mode and seeding mode. 148 cases of bone nonunion in 134 patients were treated with the modified method. Results The patients were followed up for 5.5 months to 6 years, with an average period of 2.25 years. On the average, the nonunion healed with lamellar bone 3.5 months after the operation. The healing rate was 99.3% . Conclusion The author s modified bone grafting provides a new and efficacious method for treatment of the limb nonunion.
