The Landing Error Scoring System (LESS) and Lower Limb Power Profiles in Elite Rugby Union Players

BackgroundThe Landing Error Scoring System (LESS) is a clinical test that assesses landing biomechanics during a drop-jump task. Performance measures such as jump height, power, contact time and reactive strength index are used commonly in athletic populations. Comparing results from the LESS against these performance measures has not been reported in elite rugby union.PurposeTo report i.) normative LESS scores for elite rugby union players ii.) correlations between LESS scores and performance measures and iii.) differences in performance measures between LESS scoring groups. A secondary purpose was to report the intra- and inter-rater reliability of the LESS test when used in elite rugby union players. # Study DesignCross-sectional design.MethodsThirty-six male, elite rugby union players participated. Each participant completed three trials of the LESS and performance measures were recorded concurrently using the Optojump^TM. LESS trials were scored independently by the authors. Statistical analyses were used to confirm reliability, data normality, and between group differences (p<0.05).ResultsThe LESS test is a reliable testing tool in elite rugby union players (excellent intra- (ICC=0.96) and inter-rater (ICC=0.94) reliability). One player demonstrated an excellent LESS score, six players had good scores, eight players moderate scores and the majority of the group, 21 players, scored poorly. LESS scores were correlated to contact time (r = -0.461, p = 0.005) only. Participants with moderate to poor LESS scores (a score ≤5) produced greater power (p=0.036, η2 = 0.139), contact time (p=0.002, η2 = 0.268) and reactive strength index (p=0.016, η2 = 0.180). There were no differences in jump height (p=0.842) between players scoring excellent to good and moderate to poor.ConclusionThe results of the current study demonstrate excellent intra- and inter-rater reliability for the LESS, supporting its use as a clinical assessment tool in elite rugby union players. The majority of players presented with moderate to poor LESS scores, indicating an area of concern in this population. Participants scoring moderate to poor in the LESS recorded significantly higher power and reactive strength index, increased contact time but not jump height. This suggests participants with high-risk landing biomechanics may also produce higher performance measures, but these do not necessarily result in an improved jump height.     

改良运动损伤预防方案在前交叉韧带损伤预防中的应用

目的:分析优秀女橄榄球运动员(女橄)侧切跑中,下肢运动学和动力学特征,使用改良的运动损伤预防方案对女橄运动员ACL损伤进行预防性干预并评价其效果.方法:优秀女运动员14例,随机分为实验组(REF)与对照组(CON),每组7例,实验组进行12周的康复训练,对照组不干预.采集侧切跑生物力学数据和SEMG数据.结果:①着地时...     

Swimming performances in long distance open-water events with and without wetsuit

Background

This study examined participation and performance trends in ‘Ironman Hawaii’ regarding the nationality of the finishers.

Methods

Associations between nationalities and race times of 39,706 finishers originating from 124 countries in the ‘Ironman Hawaii’ from 1985 to 2012 were analyzed using single and multi-level regression analysis.

Results

Most of the finishers originated from the United States of America (47.5%) followed by athletes from Germany (11.7%), Japan (7.9%), Australia (6.7%), Canada (5.2%), Switzerland (2.9%), France (2.3%), Great Britain (2.0%), New Zealand (1.9%), and Austria (1.5%). German women showed the fastest increase in finishers (r² = 0.83, p < 0.0001), followed by Australia (r² = 0.78, p < 0.0001), Canada (r² = 0.78, p < 0.0001) and the USA (r² = 0.69, p < 0.0001). Japanese women showed no change in the number of finishers (r² = 0.01, p > 0.05). For men, athletes from France showed the steepest increase (r² = 0.85, p < 0.0001), followed by Austria (r² = 0.68, p < 0.0001), Australia (r² = 0.67, p < 0.0001), Brazil (r² = 0.60, p < 0.0001), Great Britain (r² = 0.46, p < 0.0001), Germany (r² = 0.26, p < 0.0001), the United States of America (r² = 0.21, p = 0.013) and Switzerland (r² = 0.14, p = 0.0044). The number of Japanese men decreased (r² = 0.35, p = 0.0009). The number of men from Canada (r² = 0.02, p > 0.05) and New Zealand (r² = 0.02, p > 0.05) remained unchanged. Regarding female performance, the largest improvements were achieved by Japanese women (17.3%). The fastest race times in 2012 were achieved by US-American women. Women from Japan, Canada, Germany, Australia, and the United States of America improved race times. For men, the largest improvements were achieved by athletes originating from Brazil (20.9%) whereas the fastest race times in 2012 were achieved by athletes from Germany. Race times for athletes originating from Brazil, Austria, Great Britain, Switzerland, Germany, Australia, Canada, Japan, New Zealand and France decreased. Race times in athletes originating from Australia and the United States of America showed no significant changes. Regarding the fastest race times ever, the fastest women originated from the United States (546 ± 7 min) followed by Great Britain (555 ± 15 min) and Switzerland (558 ± 8 min). In men, the fastest finishers originated from the United States (494 ± 7 min), Germany (496 ± 6 min) and Australia (497 ± 5 min).

Conclusions

The ‘Ironman Hawaii’ has been dominated by women and men from the United States of America in participation and performance.

     

Headache service quality: evaluation of quality indicators in 14 specialist-care centres

Dopaminergic pathways could be involved in the pathophysiology of myofascial temporomandibular disorders (M-TMD). This study investigated plasma levels of dopamine and serotonin (5-HT) in patients with M-TMD and in healthy subjects. Fifteen patients with M-TMD and 15 age- and sex-matched healthy subjects participated. The patients had received an M-TMD diagnosis according to the Research Diagnostic Criteria for TMD. Perceived mental stress, pain intensity (0–100-mm visual analogue scale), and pressure pain thresholds (PPT, kPa) over the masseter muscles were assessed; a venous blood sample was taken. Dopamine in plasma differed significantly between patients with M-TMD (4.98 ± 2.55 nM) and healthy controls (2.73 ± 1.24 nM; P < 0.01). No significant difference in plasma 5-HT was observed between the groups (P = 0.75). Patients reported significantly higher pain intensities (P < 0.001) and had lower PPTs (P < 0.01) compared with the healthy controls. Importantly, dopamine in plasma correlated significantly with present pain intensity (r = 0.53, n = 14, P < 0.05) and perceived mental stress (r = 0.34, n = 28, P < 0.05). The results suggest that peripheral dopamine might be involved in modulating peripheral pain. This finding, in addition to reports in other studies, suggests that dopaminergic pathways could be implicated in the pathophysiology of M-TMD but also in other chronic pain conditions. More research is warranted to elucidate the role of peripheral dopamine in the pathophysiology of chronic pain.     

Accuracy of liver surface nodularity quantification on MDCT for staging hepatic fibrosis in patients with hepatitis C virus

Purpose

To evaluate semi-automated measurement of liver surface nodularity (LSN) on MDCT in a cause-specific cohort of patients with chronic hepatitis C virus infection (HCV) for identification of hepatic fibrosis (stages F0–4).

Methods

MDCT scans in patients with known HCV were evaluated with an independently validated, semi-automated LSN measurement tool. Consecutive LSN measurements along the anterior liver surface were performed to derive mean LSN scores. Scores were compared with METAVIR fibrosis stage (F0–4). Fibrosis stages F0–3 were based on biopsy results within 1 year of CT. Most patients with cirrhosis (F4) also had biopsy within 1 year; the remaining cases had unequivocal clinical/imaging evidence of cirrhosis and biopsy was not indicated.

Results

288 patients (79F/209M; mean age, 49.7 years) with known HCV were stratified based on METAVIR fibrosis stage: F0 (n = 43), F1 (n = 29), F2 (n = 53), F3 (n = 37), and F4 (n = 126). LSN scores increased with increasing fibrosis (mean: F0 = 2.3 ± 0.2, F1 = 2.4 ± 0.3, F2 = 2.6 ± 0.5, F3 = 2.9 ± 0.6, F4 = 3.8 ± 1.0; p < 0.001). For identification of significant fibrosis (≥ F2), advanced fibrosis (≥ F3), and cirrhosis (≥ F4), the ROC AUCs were 0.88, 0.89, and 0.90, respectively. The sensitivity and specificity for significant fibrosis (≥ F2) using LSN threshold of 2.80 were 0.68 and 0.97; for advanced fibrosis (≥ F3; threshold = 2.77) were 0.83 and 0.85; and for cirrhosis (≥ F4, LSN threshold = 2.9) were 0.90 and 0.80.

Conclusion

Liver surface nodularity assessment at MDCT allows for accurate discrimination of intermediate stages of hepatic fibrosis in a cause-specific cohort of patients with HCV, particularly at more advanced levels.

     

Hop testing symmetry improves with time and while wearing a functional knee brace in anterior cruciate ligament reconstructed athletes

BackgroundThere is currently no consensus among orthopaedic surgeons as to when patients with anterior cruciate ligament reconstruction are ready to return to sport or whether or not patients should wear a functional knee brace during athletic activity. The purpose of the present study was to determine the effects of time since return to sport and of a functional knee brace on hop distance and loading symmetry during hop testing in patients with anterior cruciate ligament reconstruction.MethodsTwenty-eight patients with anterior cruciate ligament reconstruction completed hop testing after being released to return to sport and again 3 months later, both with and without wearing a custom fit extension constraint functional knee brace. The loadsol® captured plantar loading data (100 Hz) to quantify peak impact force, loading rate, and impulse during the final landing of every hop test. A limb symmetry index was calculated between surgical and non-surgical limbs for hop distance and loading measures.FindingsWearing a knee brace increased hop distance symmetry during the single and crossover hop tests and peak impact force symmetry on each test (all p < 0.05). While single (p = 0.022) and triple (p = 0.002) hop distance symmetry increased with time, there was no effect of time on any loading symmetry outcomes.InterpretationThese results support using a functional knee brace during athletic activities for improving symmetry in the early return to sport period. These results also support previous findings that while hop distance symmetry improves with time, asymmetrical landing mechanics do not and should be addressed clinically.     

Does the 2D Frontal Plane Projection Angle Predict Frontal Plane Knee Moments during Stepping,Landing, and Change of Direction Tasks?

BackgroundAlthough dynamic knee valgus can be visually identified using the 2D frontal plane projection angle (FPPA), the validity of the FPPA in terms of predicting frontal plane knee kinematics has been questioned. The biomechanical utility of the FPPA may lie in its ability to predict frontal plane knee moments.Hypothesis/PurposeThe purpose of the current study was to comprehensively evaluate the ability of the FPPA to predict the frontal plane knee kinetics (peak moment, average moment, and moment at peak knee flexion) across a wide range of tasks (stepping, landing, and change of direction).DesignCrossover Study Design.MethodsThree-dimensional lower-extremity kinetics and 2D video were obtained from 39 healthy athletes (15 males and 24 females) during execution of six tasks (step down, drop jump, lateral shuffle, deceleration, triple hop, side-step-cut). Linear regression analysis was performed to determine if the 2D FPPA at peak knee flexion predicted frontal plane knee moment variables during the deceleration phase of each task (peak moment, average moment, moment at peak knee flexion).ResultsThe FPPA was found to significantly predict the peak frontal plane knee moment for two tasks (deceleration and side-step-cut, R² = 12% to 25%), average frontal plane knee moment for five tasks (drop jump, shuffle, deceleration, triple hop, side-step-cut, R² = 15% to 40%), and frontal plane knee moment at peak knee flexion for five tasks (drop jump, shuffle, deceleration, triple hop, side-step-cut, R2 = 16% to 45%).ConclusionAn increased FPPA (medial knee collapse) predicted increased knee valgus moments (or decreased knee varus moments) during landing and change of direction tasks (but not stepping). However, the predictive ability of the FPPA was weak to moderate.     

Unanticipated jump-landing after anterior cruciate ligament reconstruction: Does unanticipated jump-landing testing deliver additional return to sport information to traditional jump performance tests?

BackgroundWe aimed to delineate if unanticipated jump-landing assessments delivers complementary information to those of commonly used hop and jump tests after anterior cruciate ligament reconstruction.MethodsEleven participants (5 males) performed a series of unanticipated jump-landings and traditional hop and jump performance tests (single leg hops for distance, triple crossover hops for distance and drop jumps). The number of mistrials, time to stabilization and peak ground reaction force (pGRF) at landing and jump/hop distance were measured. Pearson correlations to find potential associations between the unanticipated jump-landing-values and the traditional jump/hop performance tests were calculated twice: once for the affected and once for the unaffected legs. t-Tests for dependent samples were used to detect differences between affected and unaffected leg within each test condition.FindingsThe pGRF at unanticipated landing significantly correlated to the pGRF at drop jump landing (r = 0.68) and the hopping distance after the triple crossover hops (r = 0.71, each p < .05). No other significant correlation occurred (p > .05). Hopping distance after single leg hops (mean: 110.2 cm vs. 95.5 cm) and triple crossover hops for distance (mean: 315.3 cm vs. 294.2 cm) showed significant differences between the unaffected and the reconstructed leg (p < .05). Other parameters showed no significant between-legs differences (p > .05).InterpretationBoth, the reconstructed and the contralateral leg seems to be affected. Unanticipated jump landing tasks deliver information beyond those of commonly used jump and hop tests, the thereby assessed abilities may thus be a complementary aspect of dynamic knee function than those assessed with classic tests.     

Quantitative multiparametric MR analysis of small renal lesions: correlation with surgical pathology

Purpose

The purpose of the study is to evaluate the utility of apparent diffusion coefficient (ADC), chemical shift signal intensity index (SII), and contrast enhancement in distinguishing between benign lesions and renal cell carcinoma (RCC) and between subtypes of renal lesions.

Methods

This retrospective study included 98 renal lesions (≤ 3 cm) on MRI with correlative surgical pathology. Scanner field strength, lesion location, and size were recorded. Two readers blinded to surgical pathology independently measured ADC ratio (ADC lesion/ADC non-lesion kidney), SII, and absolute/relative enhancement in the corticomedullary and nephrographic phases of contrast.

Results

There were 76 malignant and 22 benign lesions. 42 RCC were clear cell (ccRCC), 19 papillary (pRCC), 5 chromophobe (cbRCC). Benign lesions included both solid and cystic lesions. Interreader agreement for all variables was good–excellent (ICC 0.70–0.91). There was no difference in ADC or SII between benign and malignant lesions. There was greater absolute corticomedullary enhancement of benign versus malignant lesions (150.0 ± 111.5 vs. 81.1 ± 74.8, p = 0.0115), which did not persist when excluding pRCC. For lesion subtype differentiation, ADC_ratio for pRCC was lower than benign lesions (0.74 ± 0.35 vs. 1.03 ± 0.46, p = 0.0246). ccRCC demonstrated greater SII than other RCC (0.09 ± 0.22 vs. 0.001 ± 0.26, p = 0.0412). Oncocytomas and angiomyolipoma (AML) showed greater absolute corticomedullary enhancement than ccRCC and pRCC (145.6 ± 65.2 vs. 107.2 ± 85.3, p = 0.043 and 186.2 ± 93.9 vs. 37.6 ± 35.3, p = 0.0108), respectively.

Conclusions

While corticomedullary-phase enhancement was a differentiating feature, quantitative metrics from diffusion and chemical shift imaging cannot reliably differentiate benign from malignant lesions. Quantitative assessment may be useful in differentiating some benign and malignant lesion subtypes.

     

Peak Biomechanical Variables During Bilateral Drop Landings: Comparisons Between Sex (Female/Male) and Fatigue (Pre-Fatigue/Post-Fatigue)

Background

Although anterior cruciate ligament (ACL) sprains usually occur during the initial phase of the landing cycle (less than 40° knee flexion), the literature has focused on peak values of knee angles, vertical ground reaction force (VGRF), and muscle activity even though it is unclear what occurs during the initial phase of landing.

Objectives

The objectives of this study were to determine the effects of sex (male and female) and fatigue (prefatigue/post-fatigue) on knee flexion angles at the occurrence of peak values of biomechanical variables [knee valgus angle, VGRF, and normalized electromyographic amplitude (NEMG) of the quadriceps and hamstring muscles] during a bilateral drop landing task.

Methods

Knee valgus angle, VGRF, and NEMG of the quadricep and hamstring muscles were collected during bilateral drop landings for twenty-nine recreational athletes before and after a fatigue protocol.

Results

Peak values of knee valgus, VGRF, and NEMG of medial and lateral hamstring muscles occurred during the late phase of the landing cycle (>40° of knee flexion). Females in the post-fatigue condition exhibited peak VGRF at significantly less knee flexion than in the pre-fatigue condition. Males in the post-fatigue condition exhibited peak lateral hamstring muscles NEMG at significantly higher knee flexion than in the pre-fatigue condition.

Discussion and Conclusion

Peak values of biomechanical variables that have been previously linked to ACL injury did not occur during the initial phase of landing when ACL injuries occur. No biomechanical variables peaked during the initial phase of landing; therefore, peak values may not be an optimal indicator of the biomechanical factors leading to ACL injury during landing tasks.     

Relationship between KRAS mutations and dual time point 18F-FDG PET/CT imaging in colorectal liver metastases

Purpose

To investigate the association between metabolic parameters of dual time point ¹⁸F-FDG PET/CT imaging and Kirsten rat sarcoma (KRAS) mutation status in colorectal liver metastases (CRLM).

Methods

Forty-nine colorectal cancer patients with 87 liver metastatic lesions were included in this retrospective study. KRAS gene mutation tests were also performed for all the patients. The maximum standardized uptake value (SUV_max) was measured for each hepatic metastatic lesion on both early and delayed scans, and the change of SUV_max (ΔSUV_max) and retention index (RI) were calculated. Uni-variate and multi-variate analyses were employed to determine the relationship between any PET/CT parameters and KRAS mutation status.

Results

Thirty-seven (42.5%) liver metastatic lesions harboring KRAS mutations were identified. The SUV_max of CRLM with KRAS mutation both on early and delayed scans was significantly higher than those with wild-type KRAS (10.7 ± 6.0 vs. 7.8 ± 3.3, P = 0.002; 15.5 ± 10.1 vs. 10.0 ± 4.2, P < 0.001, respectively). Compared with wild-type KRAS CRLM, ΔSUV_max and RI (%) of CRLM with KRAS mutation were also significantly higher than those with wild-type KRAS (4.8 ± 4.7 vs. 2.2 ± 2.0, P < 0.001; 45.3 ± 28.2 vs. 29.6 ± 24.7, P = 0.003, respectively). Multi-variate analyses showed that the SUV_max on both early and delayed scans, ΔSUV_max, and RI (%) were the 4 independent factors to predict CRLM patients harboring KRAS mutations.

Conclusion

The SUV_max on both early and delayed scans, ΔSUV_max, and RI (%) may be the 4 independent factors to predict CRLM patients harboring KRAS mutations.

     

EFFECTS OF SURFACE ON TRIPLE HOP DISTANCE AND KINEMATICS

Background:The single leg triple hop (SLTH) test is often utilized by rehabilitation practitioners as a functional performance measure in a variety of patient groups. Accuracy and consistency are important when measuring the patient progress and recovery. Administering the SLTH test on different surfaces, consistent with the patient''s sport, may affect the hop distances and movement biomechanics.Purpose:The purpose of this study was to examine the effects of court and turf surfaces on the hop distance, limb symmetry index (LSI), and lower extremity kinematics of a SLTH test.Methods:Recreationally active female participants (n=11, height 163.8 ± 7.1cm, mass 63.1 ± 7.1kg, age 18.9 ± 0.9yrs), without injury, volunteered to participate in the study. Three maximal effort SLTH test trials on two different surfaces (court, synthetic turf) were collected and analyzed using 3D motion analysis techniques. Outcome variables included SLTH test distances and LSI values and sagittal plane kinematics including trunk, hip, knee and ankle range of motion (ROM) during the last two landings of each SLTH test trial. The second landing involves an absorption phase and propulsion phase in contrast to the final landing which involves absorption and final balance on the single leg. Paired t‐tests were used to determine differences between surfaces in hop distance and LSI values. Two‐way repeated measures ANOVA were used to determine differences between surfaces in kinematic variables.Results:The total SLTH test distance was not statistically different between the court (4.11 ± 0.47m) and turf (4.03 ± 0.42m, p=0.47) surfaces. LSI for the court surface was 100.8 ± 3.0% compared to 99.7 ± 3.0% for turf surface, which was not statistically different (p=0.30). Knee flexion ROM was significantly less (p=0.04) on the turf compared to the court surface during the second landing. Ankle flexion range of motion was also significantly less (p=0.03) during the second landing on turf compared to court.Conclusions:Type of surface influenced landing kinematics but not total SLTH test distance. When evaluating the quality of landings during a SLTH test, it may be warranted to observe each type of landing and the type of surface used during single leg tests.Level of Evidence:2     

Medial Foot Loading on Ankle and Knee Biomechanics

Background

The incidence of anterior cruciate ligament (ACL) injuries among females continues at disproportionate rates compared to males, with research indicating inconclusive multifactorial causality. Data from previous retrospective studies suggest an effect of abnormal foot and ankle bio-mechanics on pathology at the knee, including the ACL.

Objective

To determine if a relationship exists between plantar foot loading patterns during normal gait and high risk biomechanics purported to increase risk of ACL injury.

Methods

Dynamic barefoot plantar pressure distribution was measured on 33 female collegiate soccer players. Groups were divided according to their predominant gait loading pattern (medial or lateral). Three dimensional (3-D) motion analysis was conducted during drop vertical jumps to assess vertical ground reaction force and discrete angle and joint moment variables of the lower extremities.

Results

No significant differences occured in sagittal or coronal plane knee joint kinematics and kinetics between the medial and lateral loading groups.

Discussion

Dynamic foot and ankle biomechanics during gait do not appear to be related to lower extremity kinematics or kinetics during landing in collegiate female soccer players.

Conclusion

The exact cause of the abnormal differences in female landing biomechanics has not been irrefutably defined. This study suggests no effect of foot and ankle biomechanics exists on the landing mechanics of female soccer players.     

Épidémiologie des traumatismes orthopédiques liés à la pratique du rugby à XV. Revue de la littérature

Objective

To undertake a review of international epidemiological studies on match orthopedic injuries among rugby union players in order to define their frequency and some of their associated factors.

Method

Studies for this review were selected as identified by the PubMed medical database and/or published in reviewed journals. Only studies for which the methodology was described were selected at the final step.

Results

Most of the studies reviewed concerned anglo-saxon and male players. Despite the fact that the definition of injury was not the same between all studies, our review indicates that the traumatology in rugby union players is increasing since the coming of professionalism after the third IRB World Cup in 1995. Tackle was the most frequent game event cited when an injury occured but the risk for an injury was increased for scrum and collision. Muscular strains were identified as frequent injuries and prevention programs can help to reduce their incidence. Knee was the most injured localization cited for injuries with a subsequent indisponibility. As for muscle strains, prevention programs led to a decline of the frequency and the seriousness of head and spine injuries. Even though forbidden, foul play events were identified for 10 to 15% of the injuries.

Conclusion

Our review indicates that the traumatology in rugby union players is increasing since the coming of professionalism. A standardized (internal validity and reliability) and mastered methodology must be defined and applied in order to develop and to assess primary, secondary and tertiary prevention strategies.     

The single-leg vertical hop provides unique asymmetry information in individuals after anterior cruciate ligament reconstruction

BackgroundTraditional testing to identify asymmetries after anterior cruciate ligament reconstruction include four similar horizontal hopping tests. The purpose of this study was to determine whether a single-leg vertical hopping test can identify performance and biomechanical asymmetries, and whether performance asymmetries provide unique information compared to traditional tests.MethodsTwelve women with history of anterior cruciate ligament reconstruction [age: 21.1 years (SD 3.2), height: 165.8 cm (SD 6.0), mass: 68.3 kg (SD 8.8)] completed traditional horizontal hop testing. Participants also performed a single-leg vertical hop for maximal height while instrumented for three-dimensional motion analysis. Paired t-tests were performed to identify side-to-side differences in performance variables and Spearman's rank correlations were performed of limb symmetry indices to identify whether the single-leg vertical hop test provides unique information. Repeated measures MANOVAs were performed to identify single-leg vertical hop biomechanical asymmetries.FindingsParticipants exhibited significant side-to-side performance differences during the single-leg vertical hop [mean difference = 0.02 m (SD 0.03), P = .04]. Only weak to moderate relationships were identified between limb symmetry indices of the single-leg vertical hop and other horizontal hopping tests. The vertical hop elicited significant asymmetries of joint kinematics (P = .04) and angular impulse (P = .04). Specifically, the involved limb showed lower peak ankle dorsiflexion (P = .004) and knee abduction (P = .02) angles, lower sagittal plane impulse at the knee (P = .02) and greater sagittal plane impulse at the hip (P = .03).InterpretationThe single-leg vertical hop can identify performance and biomechanical asymmetries in individuals after anterior cruciate ligament reconstruction, potentially providing complementary information to standard horizontal hopping tests.     

Evaluating the size criterion for PI-RADSv2 category 5 upgrade: is 15 mm the best threshold?

Purpose

The purpose of the study was to determine if the ≥ 15 mm threshold currently used to define PIRADS 5 lesions is the optimal size threshold for predicting high likelihood of clinically significant (CS) cancers.

Materials

Three hundred and fifty-eight lesions that may be changed from category 4 to 5 or vice versa on the basis of the size criterion (category 4: n = 288, category 5: n = 70) from 255 patients were evaluated. Kendall’s tau-b statistic accounting for inter-lesion correlation, generalized estimation equation logistic regression, and receiver operating curve analysis evaluated two lesion size-metrics (lesion diameter and relative lesion diameter—defined as lesion diameter/prostate volume) for ability to identify CS (Gleason grade ≥ 3 + 4) cancer at targeted biopsy. Optimal cut-points were identified using the Youden index. Analyses were performed for the whole prostate (WP) and zone-specific sub-cohorts of lesions in the peripheral and transition zones (PZ and TZ).

Results

Lesion diameter showed a modest correlation with Gleason grade (WP: τB = 0.21, p < 0.0001; PZ: τB = 0.13, p = 0.02; TZ: τB = 0.32, p = 0.001), and association with CS cancer detection (WP: AUC = 0.63, PZ: AUC = 0.59, TZ: AUC = 0.74). Empirically derived thresholds (WP: 14 mm, PZ: 13 mm, TZ: 16 mm) performed similarly to the current ≥ 15 mm standard. Lesion relative lesion diameter improved identification of CS cancers compared to lesion diameter alone (WP: τB = 0.30, PZ: τB = 0.24, TZ: τB = 0.42, all p < 0.0001). AUC also improved for WP and PZ lesions (WP: AUC = 0.70, PZ: AUC = 0.68, and TZ: AUC = 0.74).

Conclusions

The current ≥ 15 mm diameter threshold is a reasonable delineator of PI-RADS category 4 and category 5 lesions in the absence of extraprostatic extension to predict CS cancers. Additionally, relative lesion diameter can improve identification of CS cancers and may serve as another option for distinguishing category 4 and 5 lesions.

     

Skewness of apparent diffusion coefficient (ADC) histogram helps predict the invasive potential of intraductal papillary neoplasms of the bile ducts (IPNBs)

Objective

This retrospective study was to explore the value of whole lesion apparent diffusion coefficient (ADC) histogram in distinguishing invasive and noninvasive intraductal papillary neoplasms of the bile ducts (IPNBs).

Method and materials

Fifty-two patients of IPNB underwent MRI at 1.5T with diffusion-weighted imaging (DWI, b = 500 s/mm²) before surgical resections. ADC histogram metrics were generated by using the software MR OncoTreat. The mean, standard deviation, median, skewness, kurtosis as well as the 10th, 25th, 75th, and 90th percentiles were compared between pathologically defined invasive (n = 35) and noninvasive (n = 17) IPNBs. Such conventional imaging characters as lesion location, bile duct wall dilation, and mural nodularity were also assessed. Multivariate regression analysis as well as receiver operating characteristics (ROC) analysis were then conducted to determine the predictive factors and to evaluate potential diagnostic performances.

Results

The inter-operator reliability was good to excellent (ICC: 0.693–979). Mean median, kurtosis, and the 10th, 25th, 75th, 90th percentiles were all greater in noninvasive group than invasive ones (P: 0.00–002). Skewness was lower in noninvasive group than invasive ones (− 1.0 ± 0.6 vs. − 0.3 ± 0.6, P = 0.00). After multivariate regression, skewness (AUC = 0.822, 95%CI 0.70–0.91) and mural nodularity (accuracy = 0.808) were the only two independent factors in predicting invasive IPNBs. The diagnostic performance improved (AUC = 0.867, 95%CI 0.742–0.946) when combining skewness and mural nodularity, however, the difference did not reach statistical significance (P = 0.16).

Conclusion

The ADC histogram has capability of distinguishing invasive and noninvasive IPNBs, in which skewness was an independent predictive factor.

     

Biomechanical Changes During a 90º Cut in Collegiate Female Soccer Players With Participation in the 11+

BackgroundValgus collapse and high knee abduction moments have been identified as biomechanical risk factors for ACL injury. It is unknown if participation in the 11+, a previously established, dynamic warm-up that emphasizes biomechanical technique and reduces ACL injury rates, reduces components of valgus collapse during a 90º cut.Hypothesis/PurposeTo determine whether participation in the 11+ during a single soccer season reduced peak knee abduction moment and components of valgus collapse during a 90º cut in collegiate female soccer players.Study DesignProspective cohort studyMethodsForty-six participants completed preseason and postseason motion analysis of a 90º cut. During the season, 31 players completed the 11+ and 15 players completed their typical warm-up (control group). Peak knee abduction moment, components of valgus collapse (hip adduction, internal rotation, and knee abduction angles), and a novel measure of knee valgus collapse were analyzed with repeated-measures ANOVAs to determine differences between preseason and postseason. Smallest detectable change (SDC) and minimal important difference (MID) values were applied to contextualize results.ResultsThere was a significant main effect of time for non-dominant knee valgus collapse (p=0.03), but decreases in non-dominant knee valgus collapse only exceeded the SDC in the intervention team.ConclusionsClinically meaningful decreases in knee valgus collapse may indicate a beneficial biomechanical effect of the 11+. Participation in the 11+ may lower ACL injury risk by reducing valgus collapse during a 90º cut.Level of Evidence2b     

Intrarater Reliability of Neck Strength Measurement of Rugby Union Players Using a Handheld Dynamometer

Objective

The purpose of this study was to investigate the isometric neck strength profiles of rugby union players and to assess the intrarater reliability of isometric neck strength measurement using a handheld dynamometer.

Methods

Twenty-five male, academy-level, rugby union players (forwards [n = 16], backs [n = 9]) were tested on 2 occasions during a training week 2 days apart. Isometric strength of the neck musculature was tested using a handheld dynamometer, for flexion (F), extension (E), left side flexion (LSF), and right side flexion (RSF). The average of 3 trials for each test position was used for statistical analysis. The following isometric neck strength values were obtained: F, E, F:E, LSF, RSF, LSF:RSF, and total isometric strength.

Results

Intrarater reliability intraclass correlation coefficients ranged from 0.80 to 0.92 (intraclass correlation coefficient values: F, 0.85; E, 0.85; F:E, 0.85; LSF, 0.80; RSF, 0.85; LSF:RSF, 0.91; total isometric strength, 0.92), thus indicating excellent reliability in all instances. Forwards recorded significantly greater E scores compared with backs (637.10 ± 75.15 N vs 537.87 ± 82.25 N). Forwards also recoded significantly greater total isometric neck strength scores (2151.96 ± 231.11 N vs 1814.21 ± 211.26 N).

Conclusion

The results of this study provide isometric neck strength values for the forward and back units in the rugby union and indicate that a handheld dynamometer may be a reliable tool for assessing isometric neck strength in this population.     

Effectiveness of a 12-Week Physical Exercise Program on Lower-Limb Malalignment in School-age Rugby: A Randomized Clinical Trial

ObjectiveWe sought to assess the effectiveness of 12 weeks of a physical exercise program (PEP) in child rugby players with lower-limb overpronation during gait.MethodsThis was a randomized clinical trial. A total of 123 young athletes (mean ± standard deviation age, 10.35 ± 1.22 years) were evaluated, 20 of whom had lower-limb overpronation (n = 40 extremities). Participants were randomly assigned to 2 groups: the experimental group, who performed their normal training and a PEP for 12 weeks, and the control group, who continued with their normal training for the same time. The PEP was focused on stretching the hypertonic muscle and potentiating the weakened muscles of the lower body. All participants underwent biomechanical analysis including the Helbing angle, the femorotibial angle, and the Fick angle in both limbs.ResultsAll participants (n = 20) completed the study. Baseline measurements showed no significant differences between groups in any of the variables tested. After 12 weeks, there were significant differences between groups (P < .001 for all angles). No improvement was found in the control group; however, meaningful improvement was found in all variables in the experimental group: Helbing angle (175°, P < .001, effect size [ES] = 1.94), femorotibial angle (173°, P < .001, ES = 1.77), Fick angle (12°, P < .001, ES = 1.55). The number needed to treat was 2 for femorotibial angle and Helbing angle, and 3 for Fick angle.ConclusionA 12-week PEP produced significant improvements in these 3 biomechanical variables. We also conclude that young athletes with a pathological gait pattern reached a normal gait pattern.