Isokinetic Strength Measurements Research Articles

Quadriceps Strength and Knee Function After Anterior Cruciate Ligament Reconstruction with Quadriceps Tendon Bone Autograft: A Preliminary Report.

The purpose of this study was to evaluate quadriceps strength and knee function after anterior cruciate ligament (ACL) reconstruction using a quadriceps tendon bone (QTB) autograft. Preliminary data were extracted from an ongoing prospective cohort study in which the operative extremity was compared to non-operative extremity. Patients from 14 to 40 years of age who had an ACL reconstruction with QTB autograft volunteered to have knee assessment including quadriceps isokinetic strength measures and functional knee testing at 6 and 12 months post-operatively. Paired t-tests were conducted to compare post-operative strength and function scores on participants who had minimum one-year post-surgical follow-up. Patients had a significant recovery of quadriceps strength as determined by isokinetic testing and single leg hop test. For 31 participants, quadriceps strength of the operative leg measured at 60 deg/sec was 63% of the non-operative leg at six months, increasing to 79% at one year (p < 0.001); when measured at 180 deg/sec, these values were 68% at six months, increasing to 82% at one year (p < 0.001). For 30 participants, single leg hop functional scores of the operative leg were 80% of the non-operative leg at six months, increasing to 91% at one year (p < 0.001). After QTB autograft for ACL reconstruction, there were significant gains in quadriceps strength and knee function from six months to one year post-operative. These findings indicated the QTB is an acceptable ACL reconstruction option.

Muscle architecture in patients with primary Sjögren syndrome.

This study aims to investigate skeletal muscle architecture and strength in patients with primary Sjögren syndrome (pSS). Between July 01, 2017 and November 30, 2017, 19 pSS patients (19 females; mean age: 54.1±6.6 years; range, 42 to 62 years) and 19 age-, body mass index-, and sex-matched healthy controls (19 females; mean age: 53.2±6.7 years; range 42 to 61 years) were included. Sjögren symptoms were assessed with the European Alliance of Associations for Rheumatology (EULAR) Sjögren's Syndrome Patient Reported Index (ESSPRI). Muscle thickness, pennation angle, and fascicle length were measured at quadriceps femoralis, gastrocnemius and soleus muscles. Isokinetic muscle strength tests were performed at 60 and 180°/sec for knee and at 30 and 120°/sec for ankle. Anxiety and depression evaluated with the Hospital Anxiety and Depression Scale (HADS), fatigue with Multidimensional Assessment of Fatigue scale (MAF), and functionality with Health Assessment Questionnaire (HAQ). In the pSS group, the mean ESSPRI was 7.70±1.17. The mean scores of depression (10.05±3.09 vs. 4.47±2.29; p<0.0001), anxiety (8.26±4.28 vs. 3.79±2.42; p<0.0001), functionality (0.94±0.78 vs. 0.22±0.26; p<0.0001), and fatigue (37.69±5.47 vs. 17.69±5.26; p<0.0001) were significantly higher in patients with pSS. Only, the pennation angle of vastus medialis in dominant leg was significantly greater in healthy controls (p=0.049). Peak torques/body weight of knee and ankle muscles were found to be similar. Excluding a minor decrease of the pennation angle at vastus medialis, muscle structure of lower extremity of pSS patients were similar to healthy controls. In addition, isokinetic muscle strength did not significantly differ in patients with pSS compared to healthy controls. In patients with pSS, disease activity and fatigue level were negatively correlated with isokinetic muscle strength measurements.

Inter-limb asymmetries and kicking limb preference in English premier league soccer players.

The aims of this study were: (1) to quantify interlimb asymmetries in EPL soccer players in the context of kicking limb preference and (2) to establish the relationship between interlimb asymmetries and measures of physical performance. Twenty-two players (age: 21.8 ± 4.4 years) from an EPL club performed a running gait assessment (20 km/h) and unilateral countermovement jumps, a CoD assessment (modified 505 test), and an isokinetic knee extension/flexion protocol using each leg. Asymmetries were quantified using the percentage difference method and Pearson's correlations were used to quantify the association between variables. Players displayed the greatest level of asymmetry in isokinetic strength measures (5.9–12.7%) and lower levels of asymmetry in gait (1.6–7.7%), jump (0.9–7.0%) and CoD (1.9–3.5%) assessments. The influence of the preferred kicking limb was most evident in the isokinetic assessment with the players showing dominance in the preferred limb for knee flexor strength and in the non-preferred limb for knee extensor strength. These manifested in the asymmetry values calculated for the hamstring:quadricep (H:Q) ratios at 60°/s (8.80 ± 7.82%) and 240°/s (11.22 ± 7.04%) and in the functional H:Q ratio (12.67 ± 8.25%). The asymmetry values for peak extensor moment at 240°/s showed a significant correlation (ρ = −0.55, p = 0.034) with 10 m time in the CoD assessment. These findings provide benchmark asymmetry data for soccer practitioners and reveal that kicking limb preferences may bring about interlimb differences in the H:Q ratio which raises important considerations in the design of testing batteries and injury reduction interventions.

Does Blood Flow Restriction Therapy Improve Leg Strength in Patients With a Painful Total Knee Arthroplasty?

Blood flow restriction (BFR) therapy has been proposed to help patients build strength with fewer repetitions than standard physical therapy (PT). We sought to determine if BFR would improve quadriceps and hamstring strength in patients with instability and perceived weakness >1 year after primary total knee arthroplasty (TKA). We retrospectively reviewed 48 patients with painful TKAs and flexion instability as well as quadriceps and hamstring weakness who performed a 6-week PT program and received isokinetic strength measurements (ISMs). Thirty-six patients completed a standard PT program (non-BFR) and 12 patients completed a BFR regimen. ISMs were taken before and after PT to quantify quadriceps and hamstring power, torque, and work compared to the contralateral leg. Statistical analysis was conducted on pre-PT and post-PT ISMs and decisions for revision surgery. There were no differences in ISMs after PT between the BFR and non-BFR groups. The non-BFR group showed statistically significant strength improvements in flexion but not extension (+28.7%-32.8%, P= .0145-.255). Although no significant difference was found in the BFR group, they saw improvements in all extension strength metrics (19.4%-23.4%, P= .3315-.3901) and flexion (25.7%-29.9%, P= .1994-.2392). No difference was observed between the groups in the rates of subsequent revision TKA (8.3% vs 16.7%, P= .3362). BFR did not improve quadriceps and hamstring strength compared to PT alone in patients with instability and weakness after TKA. Over 80% of total patients chose to avoid revision TKA after completion of focused PT with or without BFR.

Test-Retest Reliability of Isokinetic Strength Measurements in Lower Limbs in Elderly.

Simple SummaryStrength is a critical factor for maintaining the quality of life of elderly. The gold standard is isokinetic dynamometry. Thus, this study intended to measure intra-session reliability in lower limbs. The results provide excellent values and data on what can be considered a real change after an intervention.Strength is essential for carrying out the usual activities of daily life. As there is a loss of strength in elderly, many treatments are based on delaying the loss of strength or maintaining it. Isokinetic dynamometry is the gold standard for assessing strength. It is essential that studies are conducted to allow us to identify the reliability of isokinetic strength assessments in older people. This study aimed to test the absolute and relative intra-session reliability of peak torque and work of a concentric knee extension-flexion performed at 60°/s in elderly. Fifty-two elderly subjects performed three repetitions of bilateral concentric knee extension-flexion at 60°/s using an isokinetic dynamometer. The relative and absolute reliability were calculated between the second and third repetition. The intra-class correlation coefficient values were between 0.94 and 0.98 for peak torque and work in all measures, which is considered “excellent”, except for left leg flexors in women, with values between 0.85 and 0.88, which is considered “good”. The standard error of measurement (SEM) percentage oscillated from 3.9% to 10.5%, with a smallest real difference (SRD) percentage of 10.9% to 29.2% for peak torque. The relative reliability of peak torque and work were excellent for all measures except flexors in women, evidencing the utility of isokinetic dynamometry for monitoring lower limb maximal muscle strength and work of concentric knee extension-flexion at 60°/s/s in the elderly. In addition, an SRD > 19.9% in peak torque and an SRD > 23.1% in work is considered a true change.

The Effects of Early Range of Motion Versus Immobilization Following Acute First-Time Lateral Patellar Instability Episode: Randomized Control Trial

Background:The acute management of lateral patellar dislocations (LPD) typically consists of placing the patient in a knee immobilizer for 2 to 6 weeks, but it is not clear on how long these patients should be immobilized, if at all.Hypothesis/Purpose:The purpose of this study is to compare outcomes for patients following a rehabilitation protocol that is initiated with or without a short period of immobilization after sustaining a LPD.Methods:An IRB-approved prospective study was performed at a children’s hospital which included patients <18 years of age (mean = 14.22) diagnosed with LPD (<10 days). A total of 18 (14 females, 4 males) patients diagnosed with LPD were consented and enrolled in the study (Early ROM group = 11, Immobilization group = 7). Inclusion criteria for the study was history of knee instability, effusion or history of effusion, and (+) apprehension. Subjects were followed for 4 weeks and the following outcomes were assessed: knee ROM, isokinetic strength, Kujala, Pedi-IKDC, and Y balance scores. Split-plot (2x2) ANOVAs were conducted for each of the dependent variables with an alpha level set at .05 for the global tests and independent t-tests were run at baseline and 4 weeks.Results:There were no significant differences between groups at baseline. Knee flexion ROM showed a significant main effect of time (p≤.0005) and group (p=.012). Pedi-IKDC showed a significant main effect of time (p≤.0005) and group (p=.026). When comparing groups at 4 weeks, the early ROM group had significantly better scores in both the Kujala (means for both groups: 76.78 and 52.67), p=.049)), and the Pedi-IKDC (means for both groups: 68.85 and 40.88), p=.025)). There were no significant differences in isokinetic strength measures between the groups except for affected side knee flexion at 60 degrees/sec (p=.039) with the early ROM demonstrating higher strength. In addition, the affected side composite Y-balance scores were significantly better for the early ROM group (as compared to the immobilization group) at p=.031.Conclusion:Patients that underwent early ROM following LPD scored significantly better across patient derived outcome measures and functional outcomes at 4 weeks following the initial physical therapy evaluation when compared to a group that underwent a 2 week period of immobilization. Future studies should analyze longer term comparisons between groups to determine if this short term difference leads to long term differences or improved re-injury rates.

Effect of Lower Extremity Muscle Strength on Aerobic Capacity in Adults with Cerebral Palsy

The purpose of this study is to analyze the effect of lower extremity muscle strength of HIP joint and KNEE joint on the aerobic capacity to provide the basic data for developing an exercise program that can effectively improve the aerobic capacity of adults with cerebral palsy (CP) by identifying the part of the lower extremity muscle. A total of 18 ambulant adults with CP were recruited for this study. Seven ambulant adults with CP were excluded because they did not achieve the criteria of maximal exercise. The data from 11 subjects (11 men) with CP were used for the analysis. The mean (±SD) age, height, weight, and BMI of the subjects were 37.00 ± 12.72 years, 170.45 ± 6.37 cm, 67.02 ± 8.62 kg, and 23.09 ± 2.78 kg/m2, respectively. To measure the muscle strength of HIP joint and KNEE joint in lower extremities, the variables of the isokinetic muscle strength and the muscular endurance were performed using the isokinetic equipment (Biodex Co., Shirley, NY, USA). For the isokinetic muscle strength measurement of HIP joint, the 45°/sprotocol indicating the muscle power and the 300°/s protocol indicating the muscle endurance were used. Additionally, the measurement of KNEE joint was performed once on the left and right side, using the protocol of 60°/s indicating the muscle power and 300°/s indicating the muscular endurance. Progressive exercise tests were conducted on the treadmill (Quinton model—4500) using previously developed protocols targeting CP. The initial protocol speeds were 5 km/h−1 and 2 km/h−1 for the subjects who have been classified as Gross Motor Function Classification System (GMFCS) level I and II, respectively. Using a portable cardiopulmonary indirect breath-by-breath calorimetry system (MetaMax 3B; Cortex Biophysik, Leipzig, Germany), pulmonary ventilation (VE), respiratory exchange ratio (RER), and oxygen uptake (VO2) have been persistently measured. HR monitor (Polar Electro, Kempele, Finland polar Co. RS-800) was used to measure heart rate (HR). A correlation analysis was conducted to find out how the lower extremity muscle strength and aerobic capacity with cerebral palsy are related. Therefore, as a result, VO2peak among aerobic capacity displayed a significant positive correlation in 45° and 300°/s peak torque/BW of HIP joint, and with 60° and 300°/s peak torque/BW of KNEE joint. It was the same with 60°/s Agon/Antag ratio of KNEE Joint (p &lt; 0.05). VEpeak showed a significant positive correlation with 45° and 300°/s peak torque/BW of HIP joint, as well as correlation with 60° and 300°/s peak torque/BW and 60°/s Agon/Antag ratio of KNEE joint (p &lt; 0.05). However, HRpeak showed a significant positive correlation only in 45°/s peak torque/BW of HIP joint (p &lt; 0.05). The result of step-wise analysis was to find out which muscle strength significantly affects VO2peak and HRpeak among aerobic abilities in the lower extremity muscles of those disabled with cerebral palsy. Among the muscle functions of lower extremity muscle strength, 300°/s peak torque/BW of KNEE Joint was found to have the greatest effect on VO2peak (p &lt; 0.001). As a result, 300°/s peak torque/BW of KNEE Joint was found to be the predictable factor that could explain the VO2peak in the disabled people with cerebral palsy at 67% (R2 = 0.661). In particular, among the muscle functions of lower extremity muscle strength at 45°/s peak, torque/BW of HIP Joint was found to have the greatest effect on HRpeak (p &lt; 0.001). As a result, this factor was found to be the predictable factor that could explain the HRpeak in disabled people with cerebral palsy at 39% (R2 = 0.392). In this study, the muscle strength of the lower extremity of CP was closely related to the aerobic capacity, and the muscle endurance of KNEE Joint and the muscle power of HIP Joint were found to be important factors to predict the aerobic capacity of CP.

Maximal isokinetic elbow and knee flexor\u2013extensor strength measures in combat sports athletes: the role of movement velocity and limb side

BackgroundMaximal isokinetic strength ratios of joint flexors and extensors are important parameters to indicate the level of muscular balance at the joint. Further, in combat sports athletes, upper and lower limb muscle strength is affected by the type of sport. Thus, this study aimed to examine the differences in maximal isokinetic strength of the flexors and extensors and the corresponding flexor–extensor strength ratios of the elbows and knees in combat sports athletes.MethodForty male participants (age = 22.3 ± 2.5 years) from four different combat sports (amateur boxing, taekwondo, karate, and judo; n = 10 per sport) were tested for eccentric peak torque of the elbow/knee flexors (EF/KF) and concentric peak torque of the elbow/knee extensors (EE/KE) at three different angular velocities (60, 120, and 180°/s) on the dominant and non-dominant side using an isokinetic device.ResultsAnalyses revealed significant, large-sized group × velocity × limb interactions for EF, EE, and EF–EE ratio, KF, KE, and KF–KE ratio (p ≤ 0.03; 0.91 ≤ d ≤ 1.75). Post-hoc analyses indicated that amateur boxers displayed the largest EE strength values on the non-dominant side at ≤ 120°/s and the dominant side at ≥ 120°/s (p < 0.03; 1.21 ≤ d ≤ 1.59). The largest EF–EE strength ratios were observed on amateur boxers’ and judokas’ non-dominant side at ≥ 120°/s (p < 0.04; 1.36 ≤ d ≤ 2.44). Further, we found lower KF–KE strength measures in karate (p < 0.04; 1.12 ≤ d ≤ 6.22) and judo athletes (p ≤ 0.03; 1.60 ≤ d ≤ 5.31) particularly on the non-dominant side.ConclusionsThe present findings indicated combat sport-specific differences in maximal isokinetic strength measures of EF, EE, KF, and KE particularly in favor of amateur boxers on the non-dominant side.Trial registration: This study does not report results related to health care interventions using human participants and therefore it was not prospectively registered.

Comparison of hamstring quadriceps strength ratios in different combat sports branches

Background and Study Aim. The hamstring and quadriceps muscles can have strength differences because of the sportive activities. It is known that sportive hamstring quadriceps strength imbalance can cause decreasing sportive performance and injuries. Also, each sports branch can have a specific effect on the hamstring quadriceps strength ratio. Therefore, the aim of this study was to examine the effects of different combat sports branches on the hamstring quadriceps ratio. &#x0D; Material and Methods. Wrestlers (N=10), boxers (N=10), wushu athletes (N=10) voluntarily participated in the study (also university students). Subjects were administered standard warm-up and then a strength measurement test was performed. Subjects performed knee extensor (quadriceps) and flexor (hamstring) isokinetic strength test (concentrically) with his dominant leg at 60° angular velocity with by Cybex device (Cybex NORM®. Humac. CA. USA). Peak and average strength were recorded automatically by the device. The SPSS package program was used in the analysis of the data. The isokinetic strength measurements of three groups were analyzed with one-way ANOVA.&#x0D; Results. There were no significant differences between groups’ peak isokinetic strength ratio (wrestlers 0.58±0.09 boxers 0.56±0.07 and wushu athletes 0.57±0.12). Also, the average isokinetic strength ratio was not significantly different (wrestlers 0.56±0.08. boxers 0.60±0.08 and wushu athletes 0.53±0.11).&#x0D; Conclusions. According to the results, it can be said that combat sports athletes' hamstring quadriceps ratio can be affected by their sports branches, also by characteristics and training levels.

The Evaluation of Surgery Applied In Acute Achilles Tendon Rupture with Subjective and Objectıve Data In Accordance with Isokinetic Muscle Strength Measurement

The Evaluation of Surgery Applied In Acute Achilles Tendon Rupture with Subjective and Objectıve Data In Accordance with Isokinetic Muscle Strength Measurement

Outcomes of Tibialis Anterior Tendon Reconstruction with Autograft or Allograft.

In cases of tibialis anterior tendon (TAT) ruptures associated with significant tendon defect, an interposition graft is often needed for reconstruction. Both auto- and allograft reconstructions have been described in the literature. Our hypothesis was that both graft types would have a good integrity and provide comparable outcomes. Patients who underwent TAT reconstruction using either an auto- or allograft were identified. Patient-reported outcomes (PROs) were collected using the 12-Item Short Form Health Survey (SF-12) questionnaire, the American Orthopaedic Foot & Ankle Society (AOFAS) hindfoot score, the Foot Function Index (FFI), and the Karlsson-Peterson score. Functional outcome was assessed by isokinetic strength measurement. Outcomes were further assessed with magnetic resonance imaging (MRI) evaluation of graft integrity. All measurements were also performed for the contralateral foot. Twenty-one patients with an average follow-up of 82 months (20-262 months), comprising 12 allograft and 9 autograft TAT reconstructions, were recruited. There were no significant differences in patient-reported outcomes between allograft reconstructions and autografts: SF-12 (30.7 vs 31.1, P = .77); AOFAS (83 vs 91.2, P = .19); FFI (20.7% vs 9.5%, P = .22); and Karlsson-Peterson (78.9 vs 87.1, P = .23). All grafts (100%) were intact on MRI with a well-preserved integrity and no signs of new rupture. There were no major differences in range of motion and functional outcomes as measured by strength testing between the operative and nonoperative side. Reconstructions of TAT achieved good PROs, as well as functional and imaging results with a preserved graft integrity in all cases. There were no substantial differences between allograft and autograft reconstructions. Level IV, retrospective case series.

Relationship of the knee extensor strength but not the quadriceps femoris muscularity with sprint performance in sprinters: a reexamination and extension

PurposeThis study examined the relationships of knee extensor strength and quadriceps femoris size with sprint performance in sprinters.MethodsFifty-eight male sprinters and 40 body size-matched male non-sprinters participated in this study. The knee extensor isometric and isokinetic strengths were measured using a dynamometer. The isokinetic strength measurements were performed with slow and fast velocities at 60°/s and 180°/s, respectively. The quadriceps femoris muscle volume (MV) was measured using magnetic resonance imaging. The relative knee extensor strengths and quadriceps femoris MV were calculated by normalizing to body mass.ResultsAbsolute and relative knee extensor strengths during two velocity isokinetic contractions, but not during isometric contraction, were significantly higher in sprinters than in non-sprinters (P = 0.047 to < 0.001 for all). Such a significant difference was also observed for relative quadriceps femoris MV (P = 0.018). In sprinters, there were positive correlations between all three knee extensor strengths and quadriceps femoris MV (r = 0.421 to 0.531, P = 0.001 to < 0.001 for all). The absolute and relative strengths of the fast-velocity isokinetic knee extension correlated negatively with personal best 100-m sprint time (r = −0.477 and −0.409, P = 0.001 and < 0.001, respectively). In contrast, no such significant correlations were observed between absolute and relative quadriceps femoris MVs and personal best 100-m sprint time.ConclusionsThese findings suggest that despite the presence of the relationship between muscle strength and size, the knee extensor strength may be related to superior sprint performance in sprinters independently of the quadriceps femoris muscularity.

Bilateral Differences in Anthropometric Measurements and Isokinetic Strength Variables of Female University Netball Players

The unilateral demands on the dominant (D) limbs in netball players, may lead to developments and changes that differs from that of the non-dominant (ND) limbs. An individual who is constantly exposed to unilateral movements or repeated use of the D limb, can also develop bilateral differences between the D and ND limbs. The purpose of the study was to determine if any significant bilateral differences in anthropometric and isokinetic strength measurements occurred between the D and ND limbs of the upper and lower parts of the body in female university netball players.

Bilateral Differences in Anthropometric Measurements and Isokinetic Strength Variables of Female University Netball Players

The unilateral demands on the dominant (D) limbs in netball players, may lead to developments and changes that differs from that of the non-dominant (ND) limbs. An individual who is constantly exposed to unilateral movements or repeated use of the D limb, can also develop bilateral differences between the D and ND limbs. The purpose of the study was to determine if any significant bilateral differences in anthropometric and isokinetic strength measurements occurred between the D and ND limbs of the upper and lower parts of the body in female university netball players.

The effects of free weights and isoinertial resistance during semisquatting exercise on amateur soccer players' physical performance indicators: a randomized controlled study.

The aim of this study was to compare the effects of two lower extremity strengthening programs using isoinertial resistance or free weights on amateur soccer players' physical performance indicators. Thirty-five amateur soccer players (average age 22.6±5.1 years) were randomly assigned to isoinertial group (N.=11) or free-weight group (N.=11), or control group (N.=13). The groups performed two training sessions per week for six weeks. Before and after the strengthening implementation, physical performance indicators were evaluated, including the isokinetic knee extensors and flexors' strength, power, speed, and agility. The significance level was set at P<0.05. The isoinertial training resistance led to an increase in the hamstrings' eccentric strength at 60°/s and 150°/s (P<0.05) compared to the free-weight resistance (P>0.05) and the controls (P>0.05). No other significant adaptations were observed in the other isokinetic strength, power, speed (10-m, P=0.052) and agility measurements (Illinois Agility Test, P=0.059). In ratio (knee flexors/knee extensors) the only differences observed were at 150°/s for isoinertial group (P<0.05). Isoinertial resistance training during semisquatting can enhance the hamstrings' eccentric performance and the soccer players' speed and agility compared to the classic free-weight training program, which should consider when designing strength and injury prevention programs.

Visual cognition associated with knee proprioception, time to stability, and sensory integration neural activity after ACL reconstruction.

Visual cognitive ability has previously been associated with anterior cruciate ligament injury and injury risk biomechanics in healthy athletes. Neuroimaging reports have identified increased neural activity in regions corresponding to visual-spatial processing, sensory integration, and visual cognition in individuals after anterior cruciate ligament reconstruction (ACLR), indicating potential neural compensatory strategies for motor control. However, it remains unclear whether there is a relationship between visual cognition, neural activity, and metrics of neuromuscular ability after ACLR. The purpose of this study was to (1) evaluate the relationship between visual cognitive function and measurements of neuromuscular control (proprioception and time to stability [TTS]), isokinetic strength, and subjective function, and (2) examine the neural correlates of visual cognition between ACLR (n = 16; time since surgery 41.4 ± 33.0 months) and demographically similar controls (n = 15). Visual cognition was assessed by the ImPACT visual motor and visual memory subscales. Outcome variables of proprioception to target knee angle 20°, landing TTS, strength, and subjective function were compared between groups, and visual cognition was correlated within groups to determine the relationship between visual cognition and outcome variables controlled for time from surgery (ACLR group). The control group had better IKDC scores and strength. Visual memory and visual motor ability were negatively associated with proprioception error (r = -0.63)and TTS (r = -0.61), respectively, in the ACLR group but not controls. Visual cognition was associated with increased neural activity in the precuneus and posterior cingulate cortex in the ACLR group but not control participants. These data suggest the neural strategy in which ACLR participants maintain proprioception and stability varies, and may depend on visual cognition and sensory integration neural activity.

Biomechanical but Not Strength or Performance Measures Differentiate Male Athletes Who Experience ACL Reinjury on Return to Level 1 Sports

Background: Performance measures such as strength, jump height/length, and change of direction (CoD) time during anterior cruciate ligament (ACL) rehabilitation have been used to determine readiness to return to play and identify those who may be at risk of rerupture. However, athletes may reach these criteria despite ongoing biomechanical deficits when performing these tests. Combining return-to-play criteria with an assessment of movement through 3-dimensional (3D) biomechanics in male field sports athletes to identify risk factors for ACL rerupture has not been explored previously. Purpose: To prospectively examine differences in strength, jump, and CoD performance and movement using 3D biomechanics in a cohort of male athletes playing level 1 sports (ie, multidirectional field sports that involve landing, pivoting, or CoD) between those who reinjured the reconstructed ACL (RI group) and those with no reinjury (NRI group) after 2 years of follow-up and to examine the ability of these differences to predict reinjury. Study Design: Cohort study; Level of evidence, 2. Methods: After primary ACL reconstruction (ACLR), 1045 male athletes were recruited and underwent testing 9 months after surgery including isokinetic strength, jump, and CoD performance measures as well as patient-reported outcomes and 3D biomechanical analyses. Participants were followed up after 2 years regarding ACL reinjury status. Differences were determined between the RI and NRI groups in patient-reported outcomes, performance measures, and 3D biomechanics on the ACLR side and symmetry between limbs. The ability of these measures to predict ACL reinjury was determined through logistic regression. Results: No differences were identified in strength and performance measures on the ACLR side or in symmetry. Biomechanical analysis indicated differences on the ACLR side primarily in the sagittal plane for the double-leg drop jump (effect size, 0.59-0.64) and greater asymmetry primarily in the frontal plane during unplanned CoD (effect size, 0.61-0.69) in the RI group. While these biomechanical test results were different between groups, multivariate regression modeling demonstrated limited ability (area under the curve, 0.67 and 0.75, respectively) to prospectively predict ACL reinjury. Conclusion: Commonly reported return-to-play strength, jump, and timed CoD performance measures did not differ between the RI and NRI groups. Differences in movement based on biomechanical measures during double-leg drop jump and unplanned CoD were identified, although they had limited ability to predict reinjury. Targeting these variables during rehabilitation may reduce reinjury risk in male athletes returning to level 1 sports after ACLR. Registration: NCT02771548 (ClinicalTrials.gov identifier).

Clinical and Functional Outcomes of Peroneus Longus to Brevis Tendon Transfer.

Peroneal tendon lesions can cause debilitating pain, but operative treatment remains controversial. Some studies recommend peroneal tenodesis or transfer if more than half of the tendon is affected. However, clinical outcomes and inversion/eversion motion after peroneal transfer have not been investigated yet. Patients who underwent distal peroneus longus to brevis transfer for major peroneus brevis tendon tears with a minimum follow-up of 2 years were included. Clinical outcome parameters included the American Orthopaedic Foot & Ankle Society (AOFAS) hindfoot score, the German Foot Function Index (FFI-D), and Karlsson-Peterson score. Functional outcome was tested with a standardized active range-of-motion (ROM) and isokinetic strength measurement protocol, including concentric and eccentric eversion and inversion tests. Of total 23 eligible patients, 14 (61%) were available for follow-up. Clinical outcome scores were good with AOFAS 86 ± 16 points, FFI-D pain 26% and FFI-D disability 26%, and Karlsson-Peterson score 78 ± 23 points. There was no difference in strength in comparison to the contralateral foot (all P > .05). Isokinetic strength was 16.3 ± 4.9 Nm (108% of contralateral side) and 18.8 ± 4.5 Nm (101%) at concentric 30 deg/s and eccentric 30 deg/s eversion tests, as well as 15.7 ± 5.2 Nm (102%) and 18.7 ± 3.3 Nm (103%) at concentric 30 deg/s and eccentric 30 deg/s inversion tests, respectively. There was no difference in ROM compared to the contralateral side (eversion/inversion 14.5-0-18.7 vs 14.1-0-16.1 degrees). Peroneus longus to brevis transfer is a viable option for treating severe peroneus brevis tendon tears and does not compromise measurable strength or ROM in inversion or eversion in comparison to the contralateral ankle joint. Level IV, prospective case series.

Isometric and isokinetic muscle strength measurements of the lumbar flexors and extensors with BioniX Sim3 Pro in patients with chronic low back pain: A pilot study.

The World Health Organization states that low back pain is the leading cause for disability worldwide. Patients with chronic low back pain (CLBP) show important decreases in lumbar strength and can now be assessed by using the new isokinetic dynamometer BioniX Sim3 Pro which offers very detailed measurements. To compare lumbar flexion and extension strength values, as well as extension-flexion ratio (EFR) based on isokinetic velocity and gender, for patients with CLBP on the BioniX Sim3 Pro. A retrospective analysis was performed on data from 20 men and 22 women with CLBP. Maximum torque in flexion and extension was measured isometrically and isokinetically. Statistical analysis was performed on these parameters. EFR shows a downward trend with increasing speed of measurement (isometric to isokinetic 30∘/s and isokinetic 30∘/s to isokinetic 90∘/s, respectively): in men from 1.21 to 1.04 (p< 0.001) and from 1.04 to 0.93 (p= 0.207). In women, EFR decreased from 1.41 to 1.13 (p< 0.001) and from 1.13 to 1.00 (p= 0.144). Patients with CLBP have a decreased strength in lumbar extension and flexion compared to the age-corrected normal values of Bionix Sim3 Pro. With increasing speed of testing protocol, a decrease in EFR is observed in this population.

No functional differences in anatomic reconstruction using a one- versus a two-point fixation for distal biceps tendon rupture through a single-incision anterior approach: A prospective randomized trial.

The distal biceps brachii tendon rupture is a rare injury of the musculoskeletal system. Multiple surgical techniques have been described for distal biceps brachii tendon repairs including suture anchors. The aim of this study was to evaluate the outcome of anatomical distal biceps tendon refixation using either one or two suture anchors for reattachment and to determine whether there are significant clinically important differences on the number of anchors used for refixation. A monocentric, randomized controlled trial was conducted, including 16 male patients with a mean age of 47.4years (range, 31.0 to 58.0) in Group 1 (two suture anchors for refixation) and 15 male patients with a mean age of 47.4 (range, 35.0 to 59.0) in Group 2 (one suture anchor for refixation). All surgeries were performed through an anterior approach. The outcome was assessed using the Oxford Elbow Score (OES), the Mayo Elbow Performance Score (MEPS), the Disabilities of the Arm, Shoulder and Hand (DASH) score, the Andrews Carson Score (ACS) and by isokinetic strength measurement for the elbow flexion after six, twelve, 24 and 48 weeks. Radiographic controls were performed after 24 and 48 weeks. No significant differences between both groups were evident at any point during the follow-up period. A continuous improvement in outcome for both groups could be detected, reaching an OES: 46.3 (39.0 to 48.0) vs. 45.5 (30.0 to 48.0), MEPS: 98.0 (85.0 to 100.0) vs. 99.0 (85.0 to 100.0), DASH: 3.1 (0.0 to 16.7) vs. 2.9 (0.0 to 26.7), ACS: 197.0 (175.0 to 200.0) vs. 197.7.