ACL BONE-PATELLA TENDON-BONE AUTOGRAPH RECONSTRUCTION EFFECT ON THIGH MUSCLE GROUPS ULTRASOUND IMAGING MEASUREMENTS

Chrisha J. Newberry1, Kazuma Akehi2 & Mackenzie L. Barnes1 1Oklahoma State University, Stillwater, Oklahoma; 2University of Nebraska at Kearney, Kearney, Nebraska There is little research regarding ultrasound imaging of the muscle fibers and muscle quality for individual muscle groups of the lower extremity following an ACL reconstruction surgery. PURPOSE: The purpose of this case study was to determine if ACL bone-patella tendon-bone autograph reconstruction influenced the rectus femoris, vastus lateralis, and biceps femoris deep pennation angle, muscle thickness, and echo intensity measurements following post-ACL reconstruction rehabilitation. METHODS: A recreationally active male who received an ACL reconstruction surgery and 8-month post-surgery rehabilitation participated in this study (age=21yrs, ht=174cm, mass=82.5kg). The subject reported to the laboratory once a week for 12 weeks to obtain ultrasound images with a diagnostic ultrasound of both right and left rectus femoris, vastus lateralis, and the biceps femoris muscles. During image analysis the deep pennation angle (°), muscle thickness (cm), and muscle quality (echo intensity; 0-255 gray scale) were examined. RESULTS: The means of the image analysis are displayed in Table 1. No difference observed when comparing ipsilateral circumference across time. CONCLUSION: The average deep pennation angle and thickness of each muscle was larger in the right leg than the left leg. Echo intensity measurements showed no difference compared bilaterally. From these results, limitation in musculature pennation angle and thickness could be a potential cause for a decrease in maximal muscular performance following surgical procedures and rehabilitation of an ACL injury. Further research is needed

CORRELATES OF POWER AND VELOCITY IN THE DRIVE-BLOCK RELATIVE TO BODY MASS, FAT, AND THE 1-RM SQUAT IN DIVISION I COLLEGIATE FOOTBALL LINEMEN

Bert H. Jacobson1, FACSM, Eric C. Concola1, Doug B. Smith1, Kazuma Akehi1, Rob Glass2;1Oklahoma State University, Health & Human Performance, 2Oklahoma State University, Athletic Department, Stillwater, OK Strength and power are vital to American football players and training of these variables is constant in sophisticated, year-round preparation supervised by strength and conditioning specialists. The drive block is a principal technique in offensive line play and the squat exercise, a major staple for lower body training, is thought to relate to leg power in the task of “firing-off the line”. PURPOSE: The purpose of this study was to investigate the relationship of power (AP) and velocity (AV) to body mass (BM), fat and the 1-RM squat. METHODS: Following IRB approval 18 offensive linemen performed 10 fire-outs from a three-point stance into a stationary blocking dummy while assessments of power and velocity were made. Power (Watts) and velocity (m/sec) was recorded using a Tendo® Power and Speed Analyzer and these data were correlated with each players’ body mass, fat, and 1-RM squat. RESULTS: Means for each variable were: BM 193.82 +33.41kg, 1-RM squat 208.97 +35.93kg, fat 25.45 +6.1%, AP 1442.53 +137.46 Watts, AV 1.079 +0.09 m/sec. Correlations of the variables yielded significant (pCONCLUSION: Based on these results training protocols inclusive of squats positively relates and body fat negatively contributes to offensive line play. It is suggested that players include the squat in year-long training and attempt to replace fat by lean mass in order to maximize playing efficiency

THE INFLUENCE OF ANKLE POSITION DURING A STRAIGHT-LEG RAISE ON THE PASSIVE RESISTIVE PROPERTIES OF THE POSTERIOR HIP AND THIGH MUSCLES

Ty B. Palmer1, Kazuma Akehi1, Ryan M. Thiele1, Douglas B. Smith1, Aric J. Warren1, and Brennan J. Thompson2; 1Oklahoma State University, Stillwater, OK; 2Texas Tech University, Lubbock, TX PURPOSE: To examine the influence of ankle position on passive torque (PT), range of motion (ROM), and electromyography (EMG) of the posterior hip and thigh muscles during a passive straight-leg raise (SLR) assessment. METHODS: Thirteen healthy participants (mean±SD age=23±2yr; mass=69±15kg; height=169±10cm) performed six randomly ordered passive SLR assessments involving two assessments at each condition, which included the ankle positioned in dorsiflexion (DF), plantar flexion (PF), and a neutral (NTRL) position. All SLRs were performed using an isokinetic dynamometer programmed in passive mode to move the foot toward the head at 5°·s-1. For each SLR, participants laid in a supine position, with the knee braced in full-extension and the ankle immobilized in either 10° of DF, 10° of PF, or a NTRL (0°) position using an adjustable, custom-built stabilizing apparatus. All assessments were conducted on the right leg, while the left thigh and ankle were secured with restraining straps. Bipolar surface EMG amplitude of the biceps femoris was sampled during each SLR and expressed as a percentage of the maximal EMG amplitude that was corrected for initial baseline noise. PT and EMG amplitude were determined at four common joint angles (θ) separated by 5° during the final common 15° ROM for each participant. RESULTS: Maximum ROM was lower for the DF than the NTRL (P=0.003) and PF (P\u3c0.001) conditions. PT was greater for the DF than the NTRL and PF conditions at θ3 (P=0.001) and was greater for the DF than the NTRL condition at θ4 (P=0.003) but was not different between conditions at θ1 and θ2 (P\u3e0.05) (Figure 1). PT also increased with joint angle for the DF, PF, and NTRL conditions (P\u3c0.001). There were no joint angle or condition-related differences (P\u3e0.05) for EMG. CONCLUSION: These findings suggest that the SLRs performed with the ankle positioned in DF elicited greater PT and lower ROM of the posterior hip and thigh muscles than the SLRs with the ankle positioned in PF or a NTRL position