Objective To introduce the arthroscopic technique of figure-of-eight suture fixation for tibial eminence fracture, and to report its clinical results. Methods From January 1998 to June 2001, 21 cases of tibial eminence fracture were treated arthroscopically with figure-of-eight suture fixation technique. Active rehabilitation began one week after operation. The patients were followed up 6-24 months. The reduction and union of fracture, knee laxity, range ofmotion, and total knee function were evaluated. Results All fracture healed without displacement six weeks after operation. Three months postoperatively, no knee laxity or instability was detected in all patients; full range of motion of the affected knee returned in all patients when compared with the normal side. Six months postoperatively, the Lysholm knee score was 93.4±2.7. Conclusion Arthroscopic treatment of tibial eminence fracture with figure-of-eight suture fixation technique is reliable for fracture reduction , fixation and early mobilization. Arthroscopy is conducive to diagnoses and treatment of associated knee arthropathy, reduces the morbidity associated with arthrotomy, and restores knee function to the greatest extent when combined with figure-of-eight suture fixationtechniques.
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.
ObjectiveTo observe the changes of visual acuity and fixation properties of eyes with idiopathic macular hole (IMH) before and after surgery. MethodsA prospective clinical study. From September 2019 to December 2020, 25 patients with 25 eyes of IMH diagnosed in Department of Ophthalmology of The Fourth People's Hospital of Shenyang were included in the study. All patients underwent pars plana vitrectomy (PPV) combined with internal limiting membrane stripping. All eyes underwent best corrected visual acuity (BCVA), optical coherence tomography (OCT), and microperimetry before and after surgery. The BCVA examination was carried out using the Snellen visual acuity chart, which was converted into logarithmic minimum resolution angle (logMAR) visual acuity during statistics. The 12° macular sensitivity (MS) and bivariate contour ellipse area (BCEA) were measured by MP-3 microperimetry. The minimum diameter (MIN) and base diameter (BASE) of the macular hole were measured by OCT; the distance between the preferred retinal location (PRL) and the center of the fovea was measured by Image-proplus 6.0 image processing software. At 1 and 3 months follow-up after surgery, the same equipment and methods as before surgery were used to conduct related examinations. The changes of BCVA, PRL distance from the fovea, MS, BCEA, and macular hole shape before and after surgery were compared and observed. One-way analysis of variance was used to compare the indicators before and after surgery. Pearson correlation analysis was used for the correlation between BCVA and preoperative BCVA, PRL and foveal center distance at 3 months after surgery. The correlation between MIN, BCVA, PRL and foveal center before surgery distance, MS, BCEA and BCVA at 3 months after surgery were analyzed by multiple linear regression. ResultsAmong 25 eyes of 25 cases, 1 male had 1 eye, and 24 females had 24 eyes. The macular hole in stage Ⅲ and Ⅳ were 11 eyes and 14 eyes, respectively. MIN and BASE were 537.68±200.09 and 905.48±278.79 μm, respectively. One month after surgery, the hiatus was closed. Before surgery and 1 and 3 months after surgery, the logMAR BCVA of the affected eyes were 0.80±0.17, 0.70±0.21, 0.60±0.25, and the MS were 22.20±3.86, 23.60±3.14, 24.38±2.68 dB, the distances between PRL and the center of the fovea were 537.72±426.05, 402.00±395.06, 236.80±219.54 μm, and BCEA were 7.90±3.43, 6.40±2.67, 4.80±2.32 deg2. Compared with before operation, BCVA (F=7.047, 20.104) and MS (F=1.980, 5.390) were significantly improved at different time after operation, the distance between PRL and fovea center (F=1.265, 9.530), BCEA (F=2.762, 13.617) were decreased, the difference were statistically significant (P＜0.05). The results of correlation analysis showed that BCVA at 3 months after surgery was significantly associated with preoperative MIN (r=0.810), BASE (r=0.664), BCVA before surgery and 1 month after surgery (r=0.854, 0.940), preoperative and surgical MS at 1 month after surgery (r=－0.548, －0.578), distance between PRL and foveal center before surgery and at 1 month after surgery (r=0.833, 0.915), BCEA before surgery and at 1 month after surgery (r=0.636, 0.732) were significantly correlated (P＜0.05). The results of multiple linear regression analysis showed that the distance between PRL and foveal center before surgery and BCVA were risk factors for poor prognosis of BCVA at 3 months after surgery. ConclusionsThe BCVA and MS of eyes with IMH are significantly improved after surgery, and the distance between PRL and foveal center and BCEA decreased. BCVA, PRL and foveal center distance before surgery are risk factors for poor visual acuity after surgery.
Objective To explore the biomechanical difference between the different fixations of cortical bone plate allograft. Methods Twenty-seven cadaveric femurs were harvested and were made into the simulated fracture models, which were equally divided into Groups A, B and C. In Group A, the models were fixed with 2 bone plate allografts (110 mm×10 mm×3 mm); in Group B, the models were fixed with 2 struts (110 mm×10 mm×3 mm) and 5 bone screws; in Group C, the models were fixed with 1 strut (110 mm×10 mm×3 mm) and 5 bone screws. The biomechanical tests for the three-piont bending, torsion, and compression were performed. The parameters studied included the values of the displacements in the three-piont bending tests and the compression tests, and the maximum loads during the bending, the compression, and the torsion. Results As for all the stiffness parameters tested, Group A showed the greatest displacements among the threegroups（P＜0.05）, except the compressive stiffness parameter, which was similar to that in Group B. The maximum loads of the three-point bending, the torsion, and the compression in Group A were 1.65±0.34 kN, 554.3±49.34 N, and 7.78±0.82 Nm, respectively; in Group B, they were 1.12±0.37 kN, 428.00±37.40 N,and 3.39±0.22 Nm, respectively; in Group C, they were 0.71±0.46 kN, 218.67±36.53N, and 1.74±0.12 Nm, respectively. Group A had a significantly greater strengththan the other 2 groups(P＜0.05). Conclusion The strength of the cortical bone plate allograft is related to its different fixations. The two cortical bone plate allografts have a greater strength and stiffness than the struts fixed with the bone screws, which can meet the clinical requirement.
Objective To study the development of a physiologic fixation method and investigate the effect of physiologic fixation method on porcine aortic root and aortic valve leaflets. Methods Physiological fixer of aortic root was manufactured in a factory. The fixers with different diameter were made of organic glass. Porcine aortic root with ascending aorta and anterior leaflet of mitral valve and partial ventricular septum were dissected out from the fresh heart. The roots were attached to appropriately sized inflow and outflow spigots. Physiologic fixation was utilized to maintain aortic root and leaflets natural anatomical shape, the aortic root was pressurized to the inflow and outflow portions simultaneously, and the leaflets floated freely at zero-pressure differential with in the pressurized root. Results The process of physiologic fixation retained the properties of a native valve. The leaflets were much softer and extensible than those from valves fixed under low pressure. The results of pulsatile flow testing indicated that the effective orifice areas of predilation at 80mmHg were significantly greater than those of predilation at 40 mmHg（P〈0.05）, while mean pressure differences were found to be lower comparatively（P〈0.05）. This difference translates into a mode of valve function that more closely approximates that of the native aortic valve. Conclusion Physiologic fixation process retains the valve＇s natural anatomical shape as well as the underlying structure of the leaflets, providing improved flow characteristics.
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.
Objective To observe the relationship between position of normal central fixation and the position of the optic disc, and to find out the features of stability of fixation. Methods The position of central fixation of 120 eyes of 60 healthy adults was determined by MP-1 microperimeter. The position of central fixation relative to the position of the optic disk was measured. The relationship between the central fixation and the age or refraction was analyzed statistically. The difference between the right and left eye in each individual was analyzed with t test. Results The central fixation located at the retina with the horizontal distance of 14.48deg;plusmn;1.85deg; and vertical distance of －2.14deg;plusmn;1.26deg; from the temporal edge of the optic disk. In the 120 eyes, 90% of the central fixation located in a bivariate normal ellipse. The normal eyes usually kept in a slightly moving condition when a normal person fixing on a subject. The median of horizontal and vertical deviation was 0.4deg; and 0.3deg; respectively. Conclusion The distribution of central fixation in healthy adults is a bivariate normal ellipse. When fixing on a subject, the moving extent of the eyes in the horizontal direction is larger than that in the vertical direction.
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 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.