Clinical studies generally reveal a trend of variation in the reported prevalence of the palmaris longus (PL) muscle absence. The aim of this study was to find an answer to the question of whether the congenital absence of tendon would affect hand functions or not. A total of 585 subjects, comprised of 305 males and 280 females, were included in our study. Mean age was 8.9±1.4 standard deviation within a range of 6-11. For both sexes, the groups were divided further into three subgroups including 6-7, 8-9, and 10-11 years of age ranges. The grip strength of each hand and pinch strength of all fingers of each subject were measured separately. The absence of PL tendon in the right hand was 35.4 % in females, 25.9 % in males, and 30.4 % in overall average. The distribution of absence of the palmaris longus muscle between both genders was statistically significant. The p value for the right hand was 0.013. The absence of PL tendon in the left hand was 37.5 % in females, 27.9 % in males, and an overall average of 32.5 %. The p value for the left hand was 0.017. In terms of grip strength, a comparison between females and males did not reveal a significant difference. The pinch strength of the second fingers of both hands did not show any difference in both sexes. Pinch strength of the third finger of the right hand was different only in girls of subgroup 6-7 ages (p=0.024). In girls, the pinch strength of the fourth finger of the right hand of subgroups 6-7 and 10-11 ages showed difference (p = 0.009 and p=0.026, respectively). In boys, the fourth finger in subgroup of 8-9 ages showed significant difference in both hands (p=0.011). The fifth fingers of both hands were found different in males for only subgroup of 8-9 ages (p= 0.001). Pinch strength of the fifth finger of the right hand was different in females for only subgroups of 6-7 and 10-11 ages (p=0.023 and p=0.047, respectively). While grip strength of the hand was not affected in the case of absence of the palmaris longus, in both sexes, pinch strength of the fourth and fifth fingers of both hands decreased.

Objectives: To ascertain whether detailed isokinetic knee muscle testing reflects the results of other functional measurements in footballers and to look for any correlations between quadriceps tendon thickness and knee strength. Methods: Ultrasonographic evaluation of the quadriceps tendon (Hitachi EUB-405), isokinetic knee testing (Biodex System 3), and sprint measurements using telemetric photoelectric cells (Chronometre Prosport ESC TX02) were carried out on 29 elite footballers. Jumping capacity was evaluated using Bosco's jumping mat (Ergojump). Anaerobic fitness was assessed by auricular capillary blood lactate measurements (YSI Model 1500 Sport Lactate Analyzer). Results: Quadriceps tendon thickness correlated positively with jumping and sprint measurements and negatively with extensor and flexor strength. However, these correlations did not reach statistical significance. There were significant correlations between knee extensor strength at 60˚/s and jumping or sprint measurements and between the extension acceleration values of both knees during isokinetic tests at 240˚/s and the sprint measurements. No significant correlation was found between the fatigue ratio values of both knees at 240˚/s and the calculated fatigue ratios from the sprint measurements. Conclusions: Apart from a few variables which correlated with the performance tests, the isokinetic studies did not fully predict the various functional measurements. Neither was there any relation between the quadriceps tendon measurements and the knee strength values nor with the functional performance. I sokinetic muscle testing is often used to evaluate strength in sports medicine. A wide variety of objective and reproducible data can readily be obtained 1 2 from convenient measurements. When promptly interpreted, these data can be used to assess functional performance.Several studies have compared the results of isokinetic knee testing with certain functional measurements in footballers, who require various skills of different intensities to play their sport. [3][4][5][6][7] In this study, we aimed to ascertain whether the results of isokinetic muscle testing would reflect the results of other functional measurements in elite footballers. More precisely, we wanted to correlate several variables of isokinetic testing for predicting data acquired from the other types of measurement. The comparative evaluations for which we sought correlations were: quadriceps tendon (QT) thickness and strength, sprint, or jumping measurements; peak torque values and sprint or jumping measurements; extension acceleration times and sprint measurements; fatigue ratios during isokinetic measurements with the ratios calculated from the sprint tests or lactate analysis. MATERIALS AND METHODSThe subjects were 29 elite footballers (from a team in the first division) aged 18-31. Each player was given detailed information on the whole procedure before testing began. Ultrasonographic evaluation of the quadriceps tendonDuring the measurements, the players sat on the edge of th...

Pedicle bone screws are one of the most critical materials used in spinal orthopaedic operations. Screw loosening and pull-out (PO) are basic complications encountered during or after surgery. Pull-out Strength (POS) of the bone is one of the significant parameters to understand the mechanical behaviour of a screw fixed to poor quality or osteoporotic bone. This study investigates how the POS of a pedicle screw is affected by the factors of the screw diameter and the polyurethane (PU) foam density by experimental analysis. In the experiments, two different diameter (5.5 and 6.5 mm) of conical pedicle screws and five different density (0.08, 0.16, 0.24, 0.32 and 0.48 g·cm−3) PU foams were used. According to the force-displacement curves obtained from experimental results, the POS increased with the increases in screw diameter and PU foam density.

Acoustic emission (AE) is a nondestructive testing (NDT) technique used for detecting damages, cracks, and leaks in different structures such as metals, composites, wood, fiberglass, ceramics, plastics, etc. In recent years, AE has gained popularity within the field of biomedical applications. The structure of bone is similar to composite materials, therefore, it is advantageous to use NDT technique. Thus, it can be used for monitoring the fracture behavior, crack initiation/propagation, and fatigue detection in bones. The goal of this study was to determine the usefulness of AE techniques in fracture detection phase of bones and to develop an NDT methodology for the monitoring of crack initiation and propagation in bones. This study describes AE activity during fracture of bone tissue under tensile loads. The experiments were carried out in vitro techniques using intact and fracture-simulated bovine tibias. The specimens were loaded to failure in tension using a mechanical testing machine. During the mechanical tests, AE signals were measured and recorded by using AE system processor equipped with two wideband piezoelectric sensors fixed to the surfaces of both ends of the test specimens. By superposing the load–time curve and the cumulative AE event–time curve, AE activities of crack initiation and propagation were identified. In all experiments, the cumulative AE number for each period of time rose up exponentially with the incremental tensile load. Load for AE initiation demonstrated a convincing linear interaction with AE event generation.

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