Low back pain (LBP) is associated with altered motor control and muscle activity; however, it remains unknown whether these changes predispose humans to injury and pain or are the consequence of ongoing nociceptive processes. In this experimental study, we aimed to use a novel ultrasound imaging technique for the measurement of lateral abdominal wall muscle activity: the tissue deformation index (TDI).

Objective: Lateral ankle sprains (LASs) are prevalent in soccer and can affect long-term performance, injury recurrence and risk for chronic ankle instability. This case–control study examined functional impairments associated with LAS in professional soccer players aged 17–21.Methods: 40 players were divided into 2 groups: 21 with a history of LAS and 19 healthy matched controls. Functional assessments included the Foot and Ankle Ability Measure (FAAM), Y Balance Test (YBT), Weight Bearing Lunge Test, Heel Rise Test, Side Hop Test, and ankle and hip isometric strength measurements.Results: Soccer players with a history of LAS exhibited significant deficits in dynamic balance, particularly in the anterior and composite YBT scores, with moderate effect sizes (p<0.05). FAAM scores also revealed functional limitations in daily activities and sports performance for the LAS group. No significant differences were observed in strength or mobility measures, including the Heel Rise, Side Hop and isometric tests. There were also no differences between injured and non-injured legs in the LAS group in the performance tests.Conclusions: These findings highlight the persistent deficits in dynamic balance following LAS, emphasising the need for targeted rehabilitation to mitigate the risk of reinjury and enhance performance in soccer players.

This is a methodological study presenting a novel method of pelvic asymmetry (PA) measurement for use in the research laboratory setting. The purpose of the study is (1) to establish intrarater and interrater reliability of the proposed measures of PA, (2) to verify the influence of repeated measurements on the reliability, and (3) to assess correlation between the proposed measures of PA. Twelve healthy volunteers participated, and 2 teams of raters were involved. Registration of anatomic landmarks' positions in the optical motion capture system was repeated 3 times. Two asymmetry indexes were calculated: for pelvic torsion and for lateral pelvic tilt. Interclass correlation coefficients (ICCs), standard errors of measurement, and smallest detectable differences were used to describe the intrarater and interrater reliability of the 2 indexes. After 2 repeated registrations of pelvic landmarks' positions, the reliability of our asymmetry indexes was good and excellent. The ICCs for intrarater reliability ranged from 0.96 to 0.97; the ICCs for interrater reliability ranged 0.81 to 0.90. There was moderate, nonsignificant correlation between asymmetry indexes for pelvis torsion and for lateral pelvic tilt (r = 0.45, P = .14). The 2 proposed asymmetry indexes showed good and excellent intrarater and interrater reliability after 2 repeated registrations of pelvic landmarks' positions and thus may be useful in the research laboratory setting. However, these indexes are not strongly correlated, which suggests that the 2 types of PA may constitute different clinical entities.

Background/Objective: The effects of concomitant meniscal tears and their associated treatment on strength, lower extremity balance, and functional status after anterior cruciate ligament reconstruction (ACLR) have not been widely investigated. This study aimed to compare the functional outcomes in patients who underwent ACLR with concomitant treatment of the medial meniscus repair versus meniscectomy when returning to unrestricted physical activity. Methods: A total of 85 patients who underwent primary ACLR with combined meniscal repair (MREP; n = 39) or meniscectomy (MRES; n = 46) were assessed. The dataset included the Functional Movement Screen^TM (FMS) outcomes and single-leg balance test (SLBT) with anterior–posterior, medial–lateral, and overall stability indexes. Isokinetic knee extension and flexion strengths were tested at velocities of 60 deg·s⁻¹ and 180 deg·s⁻¹. The peak torque-to-body weight ratio (PT/BW) and limb symmetry index (LSI) were calculated. Results: In the functional assessment, there was no significant inter-group difference in the composite score of the FMS (MREP: 15.08 pts vs. MRES: 15.13 pts; p > 0.05). The SLBT outcomes in inter-group and inter-extremity comparisons were irrelevant (p > 0.05), too. Significant differences emerged in the inter-group comparison of the knee extension strength in the non-operated extremity at both 60 deg·s⁻¹ and 180 deg·s⁻¹ (p = 0.02). Inter-extremity differences were significant in both the MREP and MRES groups for knee extension and flexion at both angular velocities (all p values < 0.05). For knee extension, the LSI values ranged from 82% to 87%, and for flexion, from 77% to 84%, with no significant inter-group differences. Conclusions: Patients undergoing ACLR with concomitant meniscal repair or resection did not exhibit differences in isokinetic muscle strength, lower extremity balance, and functional tests upon returning to activity. However, participants in both groups demonstrated significant differences between the operated and non-operated extremities as far as the knee joint extensor and flexor strengths are concerned. Therefore, rehabilitation protocols should prioritize equalizing inter-extremity strength differences after the ACLR with additional treatment procedures addressing the menisci.

Introduction: Anterior cruciate ligament (ACL) reconstruction (ACLR) is the gold standard for treating ACL injuries, particularly in soccer players who are at a high risk of knee injury. While professional athletes often return to sport (RTS) within 7-10 months after ACLR, non-elite players experience significant delays. There is a need to investigate neuromuscular deficits and functional asymmetries in the non-elite group, which may persist even after clearance for RTS. This study aims to evaluate the functional movement patterns, single-leg balance, and isokinetic knee strength in non-elite soccer players preparing to RTS. Additionally, correlations between the aforementioned parameters were explored. Methods: A cohort of 69 male, non-elite soccer players (mean age: 24.32±8.56 years) who underwent ACLR with a hamstring graft was recruited. Functional assessments were conducted at the mean time of nine months post-surgery, and all participants were clinically cleared by the surgeon. The evaluation included the Functional Movement Screen™ (FMS), single-leg balance tests (SLBT) on stable and unstable platforms, and isokinetic strength tests (IST) for knee flexion and extension at 60 deg·s-1 and 180 deg·s-1. Limb symmetry indices (LSIs) were calculated. Statistical analyses included t-tests, Mann-Whitney U tests, and Spearman correlations. Results: The mean FMS score was 15.45±2.23, indicating moderate functional movement quality. SLBT results revealed no significant (P>0.05) inter-extremity differences in stability indices, regardless of platform setting (stable or unstable). However, significant deficits in quadriceps and hamstring strength were observed in the ACLR extremity. At 60 deg·s-1, the mean peak torque/body weight (PT/BW) ratio for knee extension was 2.01±0.65 Nm.kg-1 for the ACLR side versus 2.60±0.57 Nm.kg-1 for the contralateral side (P<0.0001). Similar asymmetries were observed at 180 deg·s-1 (1.51±0.44 vs. 1.88±0.35 Nm.kg-1; P<0.0001). LSIs for quadriceps were markedly reduced, averaging 76.97±17.72% at 60 deg·s-1 and 79.89±17.11% at 180 deg·s-1. At 60 deg·s-1, the mean PT/BW ratio for knee flexion was 1.24±0.34 Nm.kg-1 for the ACLR side versus 1.39±0.32 Nm.kg-1 for the contralateral side (P=0.009) at 180 deg·s-1 (1.03±0.27 vs. 1.16±0.25 Nm.kg-1; P=0.003). LSIs for the hamstring were averaging 89.34±13.91% at 60 deg·s-1 and 88.44±14.58% at 180 deg·s-1. Weak negative correlations were found between FMS scores and stability indices (e.g., r=-0.26 for overall stability index on unstable platform; P=0.031), while moderate positive correlations were observed between PT/BW ratios and FMS scores (r=0.36-0.60; P<0.001). Conclusions: Significant strength asymmetries in quadriceps and hamstring muscles persist in non-elite soccer players after ACLR. While balance deficits were minimal, weak correlations between FMS scores and stability indices suggest a link between functional movement quality and dynamic control. These findings highlight the need for targeted strength training in rehabilitation and the importance of comprehensive assessments, including functional performance tests, strength evaluations, and balance analysis, to ensure safe RTS. Achieving clinical clearance does not equate to full recovery, emphasizing the necessity for a multidimensional approach to RTS decisions.