Favorable outcomes of posterior cruciate-stabilized inserts over ultracongruent inserts in total knee arthroplasty.

Objective: Posterior cruciate-stabilized (PS) and ultracongruent (UC) inserts are used during total knee arthroplasty (TKA), but superiority in gaining postoperative knee flexion and functionality remains contested. Therefore, this study compared postoperative outcomes between PS and UC inserts.

Methods: A retrospective review evaluated unilateral or bilateral TKAs with PS or UC inserts from August 2011 to March 2020.

Musculoskeletal Injury in Reserve Officers' Training Corps: A Report From the Athletic Training Practice-Based Research Network.

Background: Reserve Officers' Training Corps (ROTC) cadets must meet the same physical standards as active duty military servicemembers and undergo organized physical training (PT). ROTC participation, like all physical activity, can result in training-related musculoskeletal injury (MSKI), and of course, cadets could sustain MSKI outside of ROTC. However, MSKI incidence in ROTC programs is largely unknown.

Fatigue-Induced Hip-Abductor Weakness and Changes in Biomechanical Risk Factors for Running-Related Injuries.

Context: Despite overlap between hip-abductor (HABD) weakness and fatigue-induced changes in running, the interaction of these theorized contributors to running injuries has been underevaluated.

Objective: To assess the effects of a fatiguing run on HABD torque and evaluate the correlation between HABD torque and previously identified running-related injury pathomechanics while participants were rested or fatigued.

Design: Crossover study.

The effect of Kinesio-tape® on pain and vertical jump performance in active individuals with patellar tendinopathy.

Background: Patellar tendinopathy is a common inflammatory condition in athletes who undergo large volumes of running and jumping. Kinesio-tape® (KT) is proposed to provide pain relief; however, its effect has not been examined on patellar tendinopathy.

Objective: To examine the effects of KT on pain modulation for active individuals with patellar tendinopathy during functional activities.

The effect of patellar thickness on gait biomechanics following total knee arthroplasty.

Background: Patella resurfacing is commonly performed during total knee arthroplasty; however, determining the appropriate patellar thickness remains a challenge. The purpose of this study was to evaluate the role of post-TKA patellar thickness on knee extensor strength and biomechanical joint loading forces during walking and stair negotiation.

Methods: Fifteen patients (21 knees) underwent gait analysis prior to TKA and post-TKA at six weeks, three months, six months, and one year.

Fixed Distal Femoral Cut of 6° Valgus in Total Knee Arthroplasty: A Radiographic Review of 788 Consecutive Cases.

Background: In place of the mechanical axis (MA), the use of the variable tibiofemoral angle is frequently used to plan measured resection bony cuts during total knee arthroplasty (TKA). This angle, coupled with operator-dependent variability of intramedullary distal femoral cutting guides, has the potential for catastrophic outcomes. Therefore, a simpler, fixed femoral cut of 6° valgus may be more appropriate when direct measurement of the MA is not possible.

The effectiveness of scaling procedures for comparing ground reaction forces.

Various scaling methods are used when attempting to remove the influence of anthropometric differences on ground reaction forces (GRF) when comparing groups. Though commonly used, ratio scaling often results in an over-correction. Allometric scaling has previously been suggested for kinetic variables but its effectiveness in partialing out the effect of anthropometrics is unknown due to a lack of consistent application.

Allometric Grip Strength Norms for American Children.

Kocher, MH, Oba, Y, Kimura, IF, Stickley, CD, Morgan, CF, and Hetzler, RK. Allometric grip strength norms for American children. J Strength Cond Res 33(8): 2251-2261, 2019-To develop normative data from a large cohort of American school children (ages 6-18) for unscaled and allometrically scaled handgrip strength data that are uninfluenced by body size (body mass [BM] and stature [Ht]).

Dynamic Varus and the Development of Iliotibial Band Syndrome.

Context:   Although the risk of osteoarthritis development after acute knee injury has been widely studied, the long-term consequences of knee overuse injury are not well understood.

Objective:   To identify the relationship between gait-related risk factors associated with osteoarthritis and the development of iliotibial band syndrome (ITBS) in members of a single University Army Reserve Officers' Training Corps unit.

Design:   Prospective cohort study.

The effects of ankle braces and taping on lower extremity running kinematics and energy expenditure in healthy, non-injured adults.

Ankle braces and taping are commonly used to prevent ankle sprains and allow return to play following injury, however, it is unclear how passive restriction of joint motion may effect running gait kinematics and energy expenditure during exercise. The purpose of this study was to determine the effect of different types of ankle supports on lower extremity kinematics and energy expenditure during continuous running. Thirteen healthy physically active adults ran at self-selected speed on the treadmill for 30min in four different ankle support conditions: semi-rigid hinged brace, lace-up brace, tape and control.

Allometric Grip Strength Norms for Children of Hawaiian Lineage.

The purpose of the study was to determine allometric exponents for scaling grip strength in children that effectively control for body mass (BM) and stature (Ht) and to develop normative grip strength data for Hawaiian children. One thousand, four hundred thirty-seven students (754 boys) from a rural community in Hawaii participated in this 5-year study, resulting in 2,567 data points. Handgrip strength, BM, and Ht were collected every year.

Asymmetry between lower limbs during rested and fatigued state running gait in healthy individuals.

Although normal gait is often considered symmetrical in healthy populations, differences between limbs during walking suggest that limbs may be used preferentially for braking or propulsion. The purpose of this study was to evaluate kinematic and kinetic variables, at both rested state and following a two-stage treadmill fatiguing run, for asymmetry between limbs. Kinematic (240Hz) and kinetic (960Hz) running data were collected bilaterally for 20 physically active individuals at both rested and fatigued states.

Standard Radiographs Are Not Sufficient for Assessing Knee Mechanical Axis in Patients With Advanced Osteoarthritis.

Background: The use of standard radiographs, and measured tibiofemoral angle (TFA), to assess lower extremity alignment is commonly practiced despite limited knowledge of its relationship to the mechanical axis (MA), as measured on hip-to-ankle (HTA) radiographs. This study assessed the predictive accuracy of previously developed equations, developed gender-specific regression equations using predictors from standard radiographs, and the clinical effectiveness of these equations in a large sample of cases using HTA radiographs as a gold standard.

Methods: The MA was measured on HTA radiographs, whereas TFA and femoral angle were measured on standard radiographs in 788 cases diagnosed with knee osteoarthritis.

Allometric scaling of strength scores in NCAA division I-A football athletes.

This study examined population-specific allometric exponents to control for the effect of body mass (BM) on bench press, clean, and squat strength measures among Division I-A collegiate football athletes. One repetition maximum data were obtained from a university pre-season football strength assessment (bench press, n = 207; clean, n = 88; and squat n = 86) and categorized into 3 groups by positions (line, linebacker, and skill). Regression diagnostics and correlations of scaled strength data to BM were used to assess the efficacy of the allometric scaling model and contrasted with that of ratio scaling and theoretically based allometric exponents of 0.

Step-rate recommendations for moderate-intensity walking in overweight/obese and healthy weight children.

Background: Physical activity guidelines for youth and adults include recommendations for moderate intensity activity to attain health benefits. Indirect calorimetry studies have consistently reported a 100 step·min(-1) threshold for moderate intensity walking in adults. No indirect calorimetry studies have investigated step-rate thresholds in children and therefore the primary purpose of the study was to determine preliminary step-rate thresholds for moderate physical activity walking in children.

Aerobic fitness levels and validation of a non exercise VO2max prediction equation for HIV-infected patients on HAART.

Background: Non-exercise (N-EX) questionnaires have been developed to determine maximal oxygen consumption (VO2max) in healthy populations. There are limited reliable and validated N-EX questionnaires for the HIV+ population that provide estimates of habitual physical activity and not VO2max.

Objectives: To determine how well regression equations developed previously on healthy populations, including N-EX prediction equations for VO2max and age-predicted maximal heart rates (APMHR), worked on an HIV+ population; and to develop a specific N-EX prediction equation for VO2max and APMHR for HIV+ individuals.

Validity and reliability of the Hawaii anaerobic run test.

This study examined the reliability and validity of the Hawaii anaerobic run test (HART) by comparing anaerobic capacity measures obtained to those during the Wingate Anaerobic Test (WAnT). Ninety-six healthy physically active volunteers (age, 22.0 ± 2.

Long-term outcomes of a dynamic ankle-foot orthosis on gait characteristics of a service member with incomplete nerve injury to the lower extremity: a case report.

This case study reports a 5-year follow-up of a 32-year-old male service member who suffered polytrauma in 2007 following a Humvee rollover in Afghanistan. The service member's injured left lower extremity was salvaged, but severe damage to the lumbosacral plexus and significant injuries to the pelvis, hip, and femur resulted in near total paralysis and foot drop of the left lower limb. Two years of multiple substandard ankle-foot orthotic devices pushed him to investigate a dynamic ankle-foot orthotic (DAFO) with energy storing capability, which allowed him to remain on active duty and deploy for a second tour while wearing the device.

Allometric scaling of Wingate anaerobic power test scores in men.

This study examined the appropriate magnitude of allometric scaling of the Wingate anaerobic test (WAnT) power data for body mass (BM) and established normative data for the WAnT for adult men. Eighty-three men completed a standard WAnT using 0.1 kg·kg(-1) BM resistance.

Validation of a nonexercise prediction equation of anaerobic power.

This study examined the validity of estimating anaerobic power in college-aged students using anthropometric data and a paper and pencil test. Peak power (PP) and mean power (MP) were determined for 157 subjects (92 men and 65 women) using a standard Wingate anaerobic test (WAnT) at a resistance of 0.075 and 0.

Comparisons of age-predicted maximum heart rate equations in college-aged subjects.

This study investigated the accuracy of age-predicted equations to predict heart rate maximum (HRmax) in a college-age sample and establish efficacy of short-duration anaerobic capacity tests to determine the actual HRmax. A criterion HRmax (CHRmax) was obtained from 96 (52 men and 44 women, age = 22.0 ± 2.

Allometric scaling of Wingate anaerobic powertest scores in women.

In this study, we developed allometric exponents for scaling Wingate anaerobic test (WAnT) power data that are effective in controlling for body mass (BM) and lean body mass (LBM) and established a normative WAnT data set for college-age women. One hundred women completed a standard WAnT Allometric exponents and percentile ranks for peak (PP) and mean power (MP) were established. Allometric exponents were applied to WAnT scores for an independent sample (n=31) to assess external validity.

Anthropometry increases 1 repetition maximum predictive ability of NFL-225 test for Division IA college football players.

The purpose of this study was to compare existing 1 repetition maximum (1RM) bench press prediction equations in National Collegiate Athletic Association (NCAA) Division IA college football players and determine if the error associated with the prediction of 1RM bench press from the National Football League (NFL)-225 test could be reduced through the addition of anthropometric measurements. Anthropometric measures, 1RM bench press, NFL-225 test repetitions to fatigue, and body composition data were collected on 87 Division IA football players (mean+/-SD age 19.9+/-1.

Development of a modified Margaria-Kalamen anaerobic power test for American football athletes.

This study examined a modification of the Margaria-Kalamen test for football players. The football stair climb test (FST) protocol used in this study increased the vertical displacement (20 steps, 3.12 m) so that the mean best time for the test was 2.