Lumbopelvic-hip Complex Research Articles

Core Stability and Its Relationship to Lower Extremity Function and Injury

Core stability may provide several benefits to the musculoskeletal system, from maintaining low back health to preventing knee ligament injury. As a result, the acquisition and maintenance of core stability is of great interest to physical therapists, athletic trainers, and musculoskeletal researchers. Core stability is the ability of the lumbopelvic hip complex to prevent buckling and to return to equilibrium after perturbation. Although static elements (bone and soft tissue) contribute to some degree, core stability is predominantly maintained by the dynamic function of muscular elements. There is a clear relationship between trunk muscle activity and lower extremity movement. Current evidence suggests that decreased core stability may predispose to injury and that appropriate training may reduce injury. Core stability can be tested using isometric, isokinetic, and isoinertial methods. Appropriate intervention may result in decreased rates of back and lower extremity injury.

Intra-subject repeatability of the three dimensional angular kinematics within the lumbo–pelvic–hip complex during running

The intra-subject repeatability of measuring the three dimensional (3D) angular kinematics of the lumbo-pelvic-hip complex during running was evaluated. Spatio-temporal parameters were found to be repeatable. All angular kinematic parameters displayed high within-day repeatability despite numerous potential sources of variability in the data. Most angular kinematic parameters also displayed high between-day and overall repeatability, except for trunk flexion-extension, lumbar spine flexion-extension, pelvic anterior-posterior tilt, hip axial rotation and thigh axial rotation. These angular parameters were highly susceptible to marker reapplication errors that produced static daily offsets in the data. Overall, the results of this study suggest that the 3D angular kinematic patterns of the lumbo-pelvic-hip complex during running can be measured with sufficient repeatability to justify the implementation of the method as an evaluation tool in future investigations. However, caution must be exerted when interpreting the absolute magnitudes of trunk flexion-extension, lumbar spine flexion-extension, pelvic anterior-posterior tilt, hip axial rotation and thigh axial rotation, given the poor level of repeatability found for these measures.

A comparison of overground and treadmill running for measuring the three-dimensional kinematics of the lumbo–pelvic–hip complex

Objective. To compare overground and treadmill running for differences in the three-dimensional angular kinematics of the lumbo–pelvic–hip complex. Design. A within-subject repeated measures design. Background. The treadmill is an attractive research instrument as speed and slope are easily controlled and the required calibration volume is reduced. However, the degree to which treadmill running simulates overground running has not been resolved in the literature to date. Methods. 10 able-bodied subjects ran overground and on a treadmill at a self-selected speed. The treadmill speed was matched to each subjects respective average overground speed. The time–distance and the three-dimensional angular kinematic data were captured using a passive marker based motion analysis system. A set of angular and temporal kinematic parameters were extracted from the data and subjected to statistical analyses. Results. Significant differences were found between overground and treadmill running for all the time–distance parameters. Despite this, the kinematics of the lumbar spine and pelvis were similar between the two running conditions, with only three parameters being significantly different. These were lumbar extension at initial contact, anterior pelvic tilt at initial contact and the first maximum anterior pelvic tilt. Hip flexion-extension parameters were also only found to display subtle differences. Of the 17 hip parameters analysed, only hip flexion at initial contact, maximum hip flexion at loading response, hip extension at toe off, maximum hip extension and hip flexion-extension range of motion were found to be significantly different. Conclusion. A high powered treadmill with a minimal belt speed fluctuation is capable of being used to obtain a representation of the typical three-dimensional kinematic pattern of the lumbo–pelvic–hip complex during running. Relevance In order for the treadmill to be accepted as a useful research and/or clinical assessment instrument, it must be demonstrated that it does not significantly alter the performance of the evaluated activity. In this respect, a treadmill with minimal intra-stride belt speed variability and similar surface stiffness to the relevant overground condition is likely to be capable of being used to obtain a representation of the typical human running action for well accommodated subjects.

DIFFERENCES IN CORE STABILITY BETWEEN MALE AND FEMALE COLLEGIATE BASKETBALL ATHLETES AS MEASURED BY TRUNK AND HIP MUSCLE PERFORMANCE

The role of lumbo-pelvic hip complex strength (often referred to as core stability) in lower extremity injuries has received recent attention. Female athletes have been shown to be at greater risk for lower extremity injuries compared to their male counterparts. Therefore, the purpose of this study was to determine if differences in trunk and hip muscle performance exist between male and female collegiate basketball athletes. Prior to the beginning of the organized season, a series of tests designed to measure core strength were conducted on 75 female and 25 male varsity collegiate basketball athletes. Endurance time of the back extensor (BE) muscles was tested using a modified Biering-Sorensen test. A side bridge (SB) test was used to measure endurance time of the quadratus lumborum and lateral trunk flexors. Abdominal (AB) muscle performance was assessed in degrees with the straight leg-lowering test. A hand-held dynamometer was used to measure isometric strength for hip external rotation (ER) and abduction (Abd). Isometric force measurments were normalized to body weight for comparisons between individuals. Student t-tests were used to compare muscle performance between males and females. Pearson correlation coefficients were calculated to examine relationships among the various muscle performance measures. Results showed that males performed significantly better than females for all of the activities tested. (See Table) Significant correlation was found between external rotation and abduction strength (r = .64). Side bridging was significantly correlated with external rotation strength (r = .58) and back extension endurance (r = .64). Weakness of key muscles of the lumbopelvic-hip complex may be related to increased risk of lower extremity injury, particularly in female athletes. This study is currently being extended to determine if athletes who perform poorly on these tests are more likely to be injured during the season.Table

The coordinated movement of the lumbo-pelvic-hip complex during running: a literature review.

The purpose of this review article is to summarise the literature to date regarding the movement of the lumbar spine, pelvis and hips during running gait. Both two-dimensional and three-dimensional studies are analysed to illustrate the apparent coordination in the angular kinematics of each of these segments during running. Knowledge of this coordination is essential in order to facilitate the successful rehabilitation of running injuries to the back, pelvis, hip and thigh.