Objective To evaluate the clinical results of bioabsorbable interference screw in knee ligament reconstruction. Methods From April 2002 to August 2004, 39 patients with knee ligament injury were treated, including 33 males and6 females with a median age of 25 years (15 to 65 years). The involved ligament included 29 anterior cruciate ligament of knee(ACL), 6 posterior cruciate ligament of knee(PCL)，4 combined ACL and PCL, 3 medial collateral or lateral collateral ligaments of knee point and 1 posterolateral complex injury of knee. All of patients underwent anatomic ligament reconstructions under arthroscopy or open surgery by autografts and fixation with bioabsorbable interference screw. Results All 34 patients were followed up 6 to 28 months (mean 13.7months). The patients were evaluated by Lysholm knee functional scales, the knee scores were 43.6±13.4 before operation and 85.4±16.3 after operation, showing significant difference (Plt;0.05). There was no limitation of rangeof motion and loosening of the screw. However, one case suffered from infection, and 3 cases suffered from effusion and synovitis after surgery and recovered after management. Conclusion Bioabsorbable interference screw fixation is a reliable method in knee ligament reconstruction and is effective to restore knee joint stability.
ObjectiveTo design an auto-compressive and anti-circumrotate intramedullary nail( ACACIN) and to evaluate the preliminary clinical efficacy on fixing adult femur fracture. Methods From January 1998 to June 2001, 23 patientswith femur fracture were stabilized with auto-compressive and anti-circumrotateintramedullary nail. 2-4 elastic blocks were installed into the proximal and distal different distance of quincunx nail to defend circumrotate and axis compress. Results Fracture healing were obtained in all 23 patients treated with auto-compresseiveand anti-circumrotate intramedullary nail, the time of fracture healing was 6-13 weeks in 21 cases and 15-22 weeks in 2 cases of old fracture. There was no complication related to infection, nail break, abnormal union and joint ankylosis. The results were excellent in 19 cases, good in 3 cases, and moderate in 1 case according Kolmert’s criterion for function ; the effective rate was 95.7%. Conclusion Auto-compressive and anti-circumrotate intramedullary nail has a suitable radian for adult femur, can afford stable fixation, anti-circumrotate andaxis compress.
ObjectiveTo investigate the classification and treatment strategies of symptomatic severe osteoporotic vertebral fracture and collapse. MethodsBetween August 2010 and January 2014, 42 patients with symptomatic severe osteoporotic vertebral fracture and collapse were treated, and the clinical data were retrospectively analyzed. According to clinical symptom and imaging materials, 23 cases were classified as type I (local pain, limitation of motion, no neurological symptom, and no obvious deformity), 12 cases as type II (slight neurological symptom and kyphotic Cobb angle ≤ 30°), and 7 cases as type III (severe neurological symptom and kyphotic Cobb angle <30°). In 23 type I patients, 17 underwent percutaneous vertebral augmentation, 6 underwent posterior pedicle screw fixation strengthened with bone cement combined with percutaneous vertebral augmentation. In 12 type II patients, they were treated with local spinal decompression and internal fixation strengthened with bone cement. In 7 type III patients, 5 underwent posterior osteotomy, and 2 underwent one stage posterior approach of vertebral resection and reconstruction. The visual analogue scale (VAS), Oswestry disability index (ODI), and local kyphotic Cobb angle were used to evaluate the neurological function. The complications were recorded. ResultsThe operation was successfully completed in all patients. Wound infection and ketoacidosis secondary to stress blood glucose rise occurred in 1 case of type III patients respectively, and were cured after corresponding treatment; primary healing of wound was obtained in the other patients. The patients were followed up from 6 to 36 months (mean, 11.6 months). The nerve function was improved in 17 cases, and micturition disability was observed in 2 cases. Asymptomatic cement leakage occurred in 13 cases (30.95%) (7 cases in type I, 4 cases in type II, and 2 cases in type III). No bone cement dislocation and internal fixation failure were found during follow-up. The VAS score, ODI, and the local kyphotic Cobb angle at 1 week and last follow-up were significantly improved when compared with preoperative ones (P<0.05), but no significant difference was found between at 1 week and last follow-up (P>0.05). ConclusionIn order to improve the effectiveness and reduce the risk and complications of operation, individualized strategies should be performed according to different types of severe osteoporotic vertebral fracture and collapse.
Although metal blocks have been widely used for reconstructing uncontained tibial bone defects, the influence of their elastic modulus on the stability of tibial prosthesis fixation remains unclear. Based on this, a finite element model incorporating constrained condylar knee (CCK) prosthesis, tibia, and metal block was established. Considering the influence of the post-restraint structure of the prosthesis, the effects of variations in the elastic modulus of the block on the von Mises stress distribution in the tibia and the block, as well as on the micromotion at the bone-prosthesis fixation interface, were investigated. Results demonstrated that collision between the insert post and femoral prosthesis during tibial internal rotation increased tibial von Mises stress, significantly influencing the prediction of block elastic modulus variation. A decrease in the elastic modulus of the metal block resulted in increased von Mises stress in the proximal tibia, significantly reduced von Mises stress in the distal tibia, decreased von Mises stress of the block, and increased micromotion at the bone-prosthesis fixation interface. When the elastic modulus of the metal block fell below that of bone cement, inadequate block support substantially increased the risk of stress shielding in the distal tibia and fixation interface loosening. Therefore, this study recommends that biomechanical investigations of CCK prostheses must consider the post-constraint effect, and the elastic modulus of metal blocks for bone reconstruction should not be lower than 3 600 MPa.
ObjectiveTo investigate the effectiveness of a modified surgical treatment of old Monteggia fracture. MethodsBetween March 2006 and December 2013, 40 cases of old Monteggia fracture were treated with modified operation. Modified operation procedure included expanding excision of pedicled forearm fascia flap for reconstruction of the annular ligament and repair of elbow radial lateral collateral ligament complex and extending osteotomy of the ulna, callus replantation, and internal fixation with steel plate. There were 26 boys and 14 girls, aged 2-10 years with an average age of 4 years. Injury was caused by falling in 24 cases, by traffic accident in 8 cases, and by falling from height in 8 cases. The disease duration was 2-11 months (mean, 4 months). Four patients had combined radial nerve palsy. ResultsIncision healed by first intention after operation, without early complication of radial nerve palsy, fascial compartment syndrome, or decreased hand extensor muscle strength. All the children were followed up 1-5 years (mean, 2.5 years). X-ray films showed fracture healing, and the healing time was 10-20 weeks (mean, 15 weeks). During follow-up, 3 cases had re-dislocation. Neither hand dysfunction caused by hand muscle adhesion nor radial head bottleneck shape change was found. On the basis of the functional evaluation criteria by Mackay, the results were excellent in 32 cases, good in 5 cases, and poor in 3 cases; the excellent and good rate was 92.5% at last follow-up. ConclusionThe modified surgical treatment of old Monteggia fracture is an effective method, with good matching of humeroradial joint and without internal fixation of the humeroradial joint.
Objective To study the effect of anterior plate fixation on the treatment of middle and lower thirds fractures of humerus and the possibility of operating without injuring the radial nerve. Methods Forty-nine patients with the middle and lower thirds fractures of the humerus were treated with anterior plate fixation from March 1998 to December 2002. Of the 49 patients, 27 were with new fractures, 12 with old fractures, and 10 with nonunion fractures. According to AO classification, of the 49 patients, there were 19 type A, 14 type B1, 9 type B2, 5 type B3, 2 type C1. Thirty-seven patients had closed fractures and 12 had open fractures. Of the 12 patients, 8 were type Gustilo Ⅰ, 4 were type Gustilo Ⅱ. Four out of the 49 patients were associated with radial nerve palsy. All patients were treatedwith anterior plate fixation through the anterior approach to the humerus. The radial nerves injured were explored. Results Of the 49 patients, 48 were followed up 6 to 48 months(28.7 months on average). All fractures were healed within 3 to 9 months(4.7 months on average). Fixed plates of 37 patients out of the 49 were removed. No iatrogenic radial nerve injury occurred in the82 times of the operations among the 49 patients. Conclusion The treatment of middle and lower thirds fractures of humerus by anterior platefixation through the anterior approach to the humerus does not interfere with the fracture healing and can prevent the iatrogenic radial nerve injury.
ObjectiveTo explore a better segment of fixation and fusion for high-grade spondylolisthesis. MethodsA total of 21 patients with high-grade spondylolisthesis who had undergone reduction and posterior instrumented fusion between July 2007 and March 2012, were retrospectively reviewed. All cases underwent posterior spinal canal decompression, Schanz screws fixation and reduction, and intervertebral and posterolateral fusion. The concept of "unstable zone" and the feature of spinal deformity helped us to identify the most appropriate segment to fuse. The pre/post-operative differences on slip percentage, pelvic incidence (PI) and lumbosacral angle were compared and analyzed. The nerve function was evaluated by physical examination and neurological Frankel grade. The Visual Analogue Scale (VAS) and Oswestry Disability Index were used to assess clinical and functional outcomes of lower limbs. Bone fusion was assessed using CT reconstruction. ResultsAll patients were followed up between 12 and 48 months. The clinical and radiological outcomes such as VAS scores and PI angle were all improved compared with that of preoperative, and the differences were all statistically significant (P<0.05). ConclusionFor children with severe spondylolisthesis, if not combined with structural scoliosis, the fixation and fusion level should be up to the upper vertebra which PI angle>60°, and try to protect the posterior longitudinal ligament complex in case adjacent segments become instability or even slip. For adults with severe spondylolisthesis, if not combined with other spinal disorders such as severe osteoporosis, only mono-segmental fusion is recommended after reduction. If the slipped vertebrae could not be reduced to Meyerding gradeⅠ, two or more segments would need to be fixed and fused.
To study project of simpl icity and util ity for screw-plate system by pedicle of atlanto-axis mani pulatively hand by X-ray film and CT to prove the one success rate of putting screws. Methods Formulate personal program was used in operation by image save transmission of X-ray film and CT during January 2002 and September 2006 in 31 patients. There were 18 males and 13 femals, aged from 23 to 61 years old with an average age of 43.5 years. Putting screw points bypedicle of atlas were measured: left (19.93 ± 1.32) mm, right (19.16 ± 1.30) mm; putting screw obl iquity angle to inside by pedicle of atlas: left (23.72 ± 2.09)°, right (23.35 ± 1.91)°; putting screw obl iquity angle to side of head by pedicle of atlas: (9.00 ± 1.20)°. Screw points by pedicle of axis: left (13.14 ± 0.82) mm right (13.85 ± 0.79) mm; putting screw obl iquity angle to inside by pedicle of axis: left (24.52 ± 1.26)°, right (20.42 ± 1.42)°; putting screw obl iquity angle to side of head by pedicle of axis: (25.00 ± 3.00)°. The domestic location toward speculum was employed in operation and putting screw points and angles were formulated by X-CT program. The pedicle screws of suitable diameter and length were of exception and screws into pedicle of atlanto-axis were put by hand. Results Pain of the greater occipital nerve occurred in 2 patients after operation and was fully recovered by treatment 1 month after operation. The lateral cortical bone of pedicle was cut by 2 screws, but the spinal cord and vertebral artery were fine. The atlas and the fracture of odontoid process of axis were completely replaced in X-ray films of all patients 1 day after operation.The position relation of lag screw and vertebral artery or spinal cord was very good in CT sheets. All cases were followed up with an average of 10.5 months during 9 months to 5 years and 4 months, and obtained atlantoaxial arthrodesis. The breakage of screw and plate was not found in all cases. According to JOA score standard, 16 cases were excellent, 12 were good, 2 were fair, 1 was poor, and the excellent and good rate was 90.32% . Conclusion The personal design and cl inical appl ication of X-ray films and CT sheets are of great significance to screw-plate system by pedicle of atlanto-axis because of simpl ification of designs and methods and better personal ity.
Objective To investigate the distribution of the preferred retinal locus (PRL) of eccentric fixation in eyes with high myopia.Methods A total of 40 highly myopic patients (54 eyes ) with eccentric fixation were examined by MP1 microperimeter to identify the PRL. The position of PRL relative to the fovea was estimated using the 90% confidence ellipse of normal adult foveal fixation. The differences of visual acuity between ldquo;desirablerdquo; and ldquo;undesirablerdquo; PRL were tested by analysis of variance.Results In 54 eyes with high myopia, 24 eyes (44.44%) had PRL of eccentric fixation below the scotoma after loss of central vision; 19 eyes ( 35.19% ) had a leftfield PRL; 6 eyes ( 11.11% ) had an upperfield PRL; and 5 eyes ( 9.26% ) had rightfield PRL. In 14 patients who had binocular eccentric fixation, 13 had the same fixation pattern in both eyes, including lowerfield PRL in 7 （50.00%）, leftfield PRL in 5 （35.71%）, and upperfield PRL in 1 patient （7.14%）. The difference of visual acuity between lower and leftfield PRL group and right and upperfield undesirable PRL group was not statistically significant（F=0.144, Pgt;0.05）. Conclusions The eccentric fixation in eyes with high myopia is usually situated as near as possible to the fovea. The optimal PRL is inferior visual field.
ObjectiveTo explore the effectiveness of a new method to repair severe soft tissue defects of the leg, foot, and ankle with contralateral saphenous neurocutaneous vascular flaps combined with assembly external frisket for fixation in parallel-leg position. MethodsBetween August 2009 and August 2013, 29 cases with leg, foot, or ankle wound were treated. There were 18 males and 11 females, with an average age of 37.6 years (range, 11-65 years). The interval of injury and operation was 14-36 days (mean, 22.3 days). The locations were the planta pedis and heel in 5 cases, the dorsal foot in 2 cases, the ankle in 4 cases, middle and lower leg in 14 cases, and upper leg in 4 cases. The area of trauma ranged from 5 cm×3 cm to 19 cm×9 cm. The assembly external frisket was used for fixation in parallel-leg position; a bridge flap was transplanted to repair defects, and the area of flap ranged from 6 cm×4 cm to 22 cm×11 cm. The donor sites were directly sutured or repaired with skin graft. The pedicle of the bridge flap was cut off and the assembly external frisket was removed after 3-4 weeks. ResultsThe flaps in all patients survived completely; primary healing of wound and incision at donor site was obtained. The patients were followed up 6-18 months (mean, 13.2 months). The appearance of flaps was satisfactory, and the sensation of the heel recovered. Moreover, the patients had a comfortable feeling, and the ankle and knee joints can move freely, and had good function. ConclusionThe assembly external frisket in parallel-leg position instead of cross-leg can make patients comfortable position, and achieve reliable fixation. The saphenous neurocutaneous vascular flap has the advantages of no need for anastomosis vein and for sacrifice of the main vein. Contralateral saphenous neurocutaneous vascular flap combined with assembly external frisket for fixation in parallel-leg position is a favorite method to repair severe soft tissue defects of the leg, foot, and ankle.