Edmar Stieven Filho

Effects of a highly concentrated platelet-rich plasma on the bone repair using non-critical defects in the calvaria of rabbits

PURPOSE To verify the effect of highly concentrated platelet-rich plasma (hPRP) in the pathways of bone repair using non-critical defects in the calvaria of rabbits. METHODS The hPRP was produced from collected venous blood of 21 rabbits. Four non-critical defects of 8 mm in diameter were created on the calvaria of each animal. The defects were all treated differently: autogenous particled bone (APB, group 1), autogenous particled bone associated with hPRP (APB + hPRP, group 2), isolated hPRP (group 3), and blood clot (control, group 4). Animals were submitted to euthanasia on the 2nd, 4th and 6th week postoperatively. Histological and histomorphometric analysis were carried through. RESULTS After two weeks, groups 1 and 2 were in more advanced stage of repair than 3 and 4. At this period, comparing the groups 1 and 2, no significant differences were found between both, which also happened between the groups 3 and 4. However, after four and six weeks, the group 1 showed a more advanced stage of repair among all the other studied groups, while group 2 was in more advanced signs of bone repair than groups 3 and 4. Comparing groups 3 and 4, after four and six weeks, the least advanced stage of bone repair was found to be within group 3. CONCLUSION The use of a highly concentrated PRP was considered prejudicial to the repair of non-critical defects in the calvaria of rabbits, either in the association of autogenous particled bone, when compared to autogenous particled bone alone, or in its isolated form, when compared to blood clot (control).

Análise biomecânica da solidarização de tendões para reconstrução do ligamento cruzado anterior

OBJECTIVE:To evaluate the difference of the mechanical behavior of bended tied (sewed) and not tied hamstring tendons in order to evaluate if it has any effective function. METHODS: Twenty-four fresh bovine digital tendons had been used. Alginate to determine the area of the tendon transversal section was used. Ten bovine tendons had been bended and tied following the manufacturer orientation, ten others pairs had not been tied. Claws had been developed for the grafts fixation to the universal machine, for the setting simulation. The superior one was characterized to be bipartite and to have controlled passage for the pins and the inferior claw is characterized to have alternating teeth. RESULTS: The maximum load of the not tied samples of the test was 849,4 N ± 386,8 the area was 30,4 mm2 ± 7,7, and 29 ± 17 Mpa of tension. The tied ones had gotten maximum load of 871,8 N ± 484,9, area of 35 mm2 ± 5,8, and 24 ± 10 Mpa of tension. It did not have statistical difference between the two groups (p>0,05). CONCLUSION: The probability distribution showed that with 400 N the not tied tendons represents 83,8% of trustworthiness and the tied ones represents 78,5%.

Hamstring tendons insertion - an anatomical study

Objective To study the anatomy of the hamstring tendons insertion and anatomical relationships. Methods Ten cadaver knees with medial and anterior intact structures were selected. The dissection was performed from anteromedial access to exposure of the insertion of the flexor tendons (FT), tibial plateau (TP) and tibial tuberosity (TT). A needle of 40 × 12 and a caliper were used to measure the distance of the tibial plateau of the knee flexor tendons insertion at 15 mm from the medial border of the patellar tendon and tibial tuberosity to the insertion of the flexor tendons of the knee. The angle between tibial plateau and the insertion of the flexor tendons of the knee (A-TP-FT) was calculated using Image Pro Plus software. Results The mean distance TP-FT was 41 ± 4.6 mm. The distance between the TT-FT was 6.88 ± 1 mm. The (A-TP-FT) was 20.3 ± 4.9°. Conclusion In the anterior tibial flexor tendons are about 40 mm from the plateau with an average of 20°.

Pseudoaneurysm after arthroscopic procedure in the knee

The aim of this study was to review all cases of pseudoaneurysm in the literature, in predominantly arthroscopic procedures on the knee, and to report on a case of pseudoaneurysm that we treated. A bibliographic search was conducted for scientific articles published in Brazilian and foreign periodicals over the last 23 years. Forty-seven cases were found, in 40 articles. In addition to these 47 cases, there was the case that we treated, which was also included in the data. Among the operations that progressed with formation of a pseudoaneurysm, 60% were cases of meniscal injuries and 23%, anterior cruciate ligament injuries. In 46% of the cases, the artery affected with the popliteal, and in 21%, the inferomedial genicular artery. The commonest clinical symptom was pain (37%), followed by pulsating tumor (31%), edema of the calf (12%) and hemarthrosis (11%). The median time taken to make the diagnosis was 11 days, but it ranged from one day to 10 weeks after the procedure. Although rare, pseudoaneurysms are a risk that is inherent to arthroscopic surgery. All patients should be made aware of the vascular risks, even in small-scale procedures.

Biomechanical analysis on transverse tibial fixation in anterior cruciate ligament reconstructions

Objective To verify whether the combination of tibial cross pin fixation and femoral screw fixation presents biomechanical advantages when compared to femoral cross pin fixation and tibial screw fixation for the reconstruction of the anterior cruciate ligament (ACL). Methods Thirty-eight porcine knees and bovine extensor digitorum tendons were used as the graft materials. The tests were performed in three groups: (1) standard, used fourteen knees, and the grafts were fixated with the combination of femoral cross pin and a tibial screw; (2) inverted, used fourteen knees with an inverted combination of tibial cross pin and a femoral screw; (3) control, ten control tests performed with intact ACL. After the grafts fixation, all the knees were subjected to tensile testing to determine yield strength and ultimate strength. Results There was no statistically significant difference in survival techniques in regard to strength, yield load and tension. There was a higher survival compared in the standard curves of yield stress (p < 0.05). Conclusion There is no biomechanical advantage, observed in animal models testing, in the combination of tibial cross pin fixation and femoral screw when compared to femoral cross pin fixation and tibial screw.

Anatomical study of the posterior cruciate ligament with the knee flexed at 90

Objective To study the anatomy of the posterior cruciate ligament (PCL) and define anatomical parameters with the knee flexed at 90°. Methods Eight knees from cadavers were dissected in order to make measurements from the center of the anterolateral band to the roof (AL1), from the center of the anterolateral band to the anterior cartilage (AL2), from the center of the posteromedial band to the roof (PM1), from the center of the posteromedial band to the anterior cartilage (PM2), from the center of the tibial insertion to the medial region of the tibia (TIM), from the center of the tibial insertion to the lateral region of the tibia (TIL), from the center of the medial insertion to the medial meniscus (IMM) and the width of the origin of the PCL (WO). To obtain the results from each anatomical structure, the means and standard deviations of the measurements were calculated. Results The measurements in millimeters that were found were AL1, 6.2; AL2, 4.9; PM1, 11.7; PM2, 5.5; TIM, 32.5; TIL, 40.6; IMM, 9.4; and WO, 32.5. Conclusions The PCL has an extensive origin. The center of the anterolateral band is 6 mm from the roof and 5 mm from the anterior cartilage of the knee. The tibial insertion is slightly medial and 10 mm distal to the posterior cornu of the medial meniscus.

Oblique popliteal ligament - an anatomical study

Objective To study the anatomy of the oblique popliteal ligament, as regards its dimensions, expansion and anatomical relationships. Methods Eleven cadaver knees were dissected in order to study the anatomy and take measurements of anatomical structures and relationships of the oblique popliteal ligament. The dissection was for posterior access to the proper exposure of the oblique popliteal ligament, the semimembranosus muscle and its expansions. For measurement of dimensions, 40 × 12 needles were used for marking the specific points and a caliper. The angles were calculated using the software ImagePro Plus®. Results The distance from the origin of the oblique popliteal ligament to the tibial plateau was 7.4 mm, the thickness at its origin was 7.3 mm, length was 33.6 mm and the tibial plateau angle 34.8°. The length of the expansion of the proximal oblique popliteal ligament was 39.2 mm, thickness 7.8 mm and angle of the oblique popliteal ligament with its expansion 32.2°. Conclusion The oblique popliteal ligament is thick, rises in the semimembranosus and protrudes proximally forming an acute angle with the joint interline, crossing the popliteal fossa. In some cases it has a proximal expansion.

É possível prever o comprimento de tendões flexores do joelho por antropometria

OBJECTIVE To compare the anthropometric data and the sportive way of life with the hamstring tendons dimensions, prospectively, in order to create a rule to predetermine its dimensions. METHODS General and anthropometric data were collected from 30 patients that were submitted to anterior cruciate ligament reconstruction. These data were correlated to the diameter and length of the hamstring tendons. The data collected were: height, weight, age, knee lesion side, body mass, sportive training level, femoral length, tibia length, thigh circumference, and knee circumference. The correlation was made by Pearson coefficient. RESULTS Statistic significant correlation occurred only with height and tibia length versus the gracilis and semitendinous tendon length. Using linear regression the relations found could be expressed with the following formulas: semitendinous length = -2.276 + 0.177 x height; semitendinous length = 13.048 + 0.46 x tibia height; gracilis length = -9.413 + 0.207 x height; gracilis length = 7.036 + 0.583 x tibia height. CONCLUSION It is possible to predetermine hamstring tendons length through linear regression formulas before surgical intervention.

Biomechanical analysis of a double fixation method for tendon graft in porcine tibia – using an interference screw plus staple

Objective The aim of the study was to compare the mechanical behavior of interference screw tibial fixation vs. screw-plus-staple tibial fixation in an animal model. Methods Thirty-six pieces of swine knee specimens were selected and divided into two groups: Group 1, tibial fixation with interference screw (n = 17), and Group 2, fixation with interference screw and staple (n = 19). The models were submitted to a single cycle of tension testing. The following variables were measured: graft cross-sectional area, failure point on 10 mm (F10), yield load (Fy), and stiffness. Results The mean values of graft cross-sectional area, F10, Fy, and stiffness did not present significant differences between the groups. Conclusion The addition of a second staple-type ligament fixation device, complementing the interference screw, did not increase the mechanical safety of the system.

ANÁLISE DA ALTURA DO SORO NO FLUXO DE SAÍDA DE EQUIPO USADO PARA ARTROSCOPIA

Introduction: This study aims to analyze the influence of the height of the saline bags in output stream or flow of fluid through a 4-spike gravity tubing set delivery unit coupled to a arthroscopic sheath and 4 mm arthroscope. Methods: Was analyzed the flow time of 0.9% saline by 4-spike gravity tubing set, engaged in a arthroscopic sheath and arthroscope, to achieve the volume of 2000 and 4000 mL. Were performed 20 experimental tests, divided in two groups: Group 1 - support raised to a height of 80 cm, Group 2 - support raised to a height of 150 cm. Results: The mean flow on tests with saline bags raised to 80 cm was 7,78 cm3/s in the time period elapsed until the flow of 2000 mL and 6.82 cm3/s to 4000 mL. With the elevation of saline bags to 150 cm, the average flux was 12.11 cm3/s during the filling of 2000 mL and 10.59 cm3/s to 4000 mL. Conclusion: The increases height of the saline bags of 80 cm to 150 cm increased to 60% in the flow of saline solution.