Larger hip external rotation motion is associated with larger knee abduction and internal rotation motions during a drop vertical jump

Associations among hip motions, knee abduction and internal rotation motion during a drop vertical jump (DVJ), which increases the risk of anterior cruciate ligament injury, remain unclear. The purpose of this study was to examine associations among knee abduction, internal rotation and hip joint motions during a DVJ. Fifty-seven young female participants performed a DVJ from a 30-cm height. Hip and knee kinematics and kinetics were analysed using a three-dimensional motion analysis system and force plates. Multiple regression analysis showed that peak knee abduction angle was negatively associated with knee internal rotation and hip internal rotation excursions from initial contact (IC) to peak knee flexion, and positively associated with peak knee abduction moment (R2 = 0.465, P< 0.001). Peak knee internal rotation angle was negatively associated with the hip flexion excursion from IC to peak knee flexion and peak hip adduction moment (R2 = 0.194, P= 0.001). In addition, hip internal rotation excursion was negatively associated with knee abduction and internal rotation excursion from IC to 50 ms after IC. To avoid a large knee abduction and internal rotation motion during jump-landing training, it might be beneficial to provide landing instructions to avoid a large hip external rotation motion.

Does Increased Femoral Anteversion Can Cause Hip Abductor Muscle Weakness?

BACKGROUND

Increased femoral anteversion (IFA) causes functional problems (i.e., tripping, frequently falling, and fatigue) by affecting the pelvis and lower extremity biomechanics. In the frontal plane, increased contralateral pelvic drop and ipsilateral hip adduction, which are mainly considered deteriorated hip abductor muscle mechanisms, are associated with hip and knee injuries.

AIMS

The aim of this study was to examine the effects of femoral anteversion on hip abductor weakness and frontal plane pelvis-hip biomechanics during walking.

METHODS

The study included nine subjects with increased femoral anteversion and a control group of eleven subjects. Maximum isometric voluntary contraction (MIVC) values of the hip abductor muscles were measured with a handheld dynamometer. Three-dimensional gait analysis was performed for kinetic, kinematic, and temporo-spatial gait parameters. Non-parametric tests were used for statistical analysis (p < 0.05).

RESULTS

There was no significant difference found between the MIVC values of the IFA and control groups (p = 0.14). Moreover, no significant difference was determined between the ipsilateral peak hip adduction (p = 0.088) and contralateral pelvic drop (p = 0.149) in the stance phase. Additionally, there was no correlation between the peak hip adduction angle in the stance phase and normalized MIVC values in the IFA group (r = -0.198, p = 0.44), or in the control group (r = -0.174, p = 0.55). The deviations of pelvic rotation (p = 0.022), hip internal rotation (p = 0.003), and internal foot progression (p = 0.022), were found to be higher in the IFA group than in the controls.

CONCLUSIONS

IFA may not be associated with hip abductor muscle weakness, and it may not lead to the hip adduction and pelvic depression that can be seen in hip abductor weakness. Increased pelvic rotation and internal hip rotation during walking might be considered as a compensation for the femoral head-acetabulum alignment mechanism in the frontal plane.

Lower Extremity Biomechanics During a Drop-Vertical Jump and Muscle Strength in Women With Patellofemoral Pain

CONTEXT

Patellofemoral pain (PFP) is one of the most prevalent knee conditions observed in women. Current research suggests that individuals with PFP have altered muscle activity, kinematics, and kinetics during functional tasks. However, few authors have examined differences in lower extremity biomechanics in this population during the drop-vertical jump (DVJ).

OBJECTIVE

To determine how lower extremity electromyography, kinematics, and kinetics during a DVJ and lower extremity isometric strength differed between women with and those without PFP.

DESIGN

Cross-sectional study.

SETTING

Laboratory.

PATIENTS OR OTHER PARTICIPANTS

Fifteen healthy women (age = 20.23 ± 1.39 years, height = 169.32 ± 5.38 cm, mass = 67.73 ± 9.57 kg) and 15 women with PFP (age = 22.33 ± 3.49 years, height = 166.42 ± 6.01 cm, mass = 65.67 ± 13.75 kg).

INTERVENTION(S)

Three trials of a DVJ.

MAIN OUTCOME MEASURE(S)

Surface electromyography, kinematics, and kinetics were collected simultaneously during a DVJ. Lower extremity strength was measured isometrically. Independent-samples t tests were performed to assess group differences.

RESULTS

Normalized muscle activity in the vastus medialis (healthy group = 120.84 ± 80.73, PFP group = 235.84 ± 152.29), gluteus maximus (healthy group = 43.81 ± 65.63, PFP group = 13.37 ± 13.55), and biceps femoris (healthy group = 36.68 ± 62.71, PFP group = 11.04 ± 8.9) during the landing phase of the DVJ differed between groups. Compared with healthy women, those with PFP completed the DVJ with greater hip internal-rotation moment (0.04 ± 0.28 N/kg versus 0.06 ± 0.14 N/kg, respectively) and had decreased knee-flexion excursion (76.76° ± 7.50° versus PFP = 74.14° ± 19.85°, respectively); they took less time to reach peak trunk flexion (0.19 ± 0.01 seconds versus 0.19 ± 0.02 seconds, respectively) and lateral trunk flexion (0.12 ± 0.07 seconds versus 0.11 ± 0.04 seconds, respectively).

CONCLUSIONS

During the DVJ, women with PFP had increased hip internal-rotation moment and decreased knee-flexion excursion with less time to peak trunk flexion and lateral flexion. Muscle activation was increased in the vastus medialis but decreased in the gluteus maximus and biceps femoris. This suggests that altered motor-unit recruitment in the hip and thigh may result in changes in biomechanics during a DVJ that are often associated with an increased risk of injury.

Effects of running biomechanics on the occurrence of iliotibial band syndrome in male runners during an eight-week running programme-a prospective study

Iliotibial band syndrome (ITBS) is a common injury that is related to running biomechanics. This study aimed to determine the gait characteristics that easily induce ITBS and explore the gait changes after the occurrence of ITBS. Thirty healthy male recreational runners participated in our study. Amongst them, 15 developed ITBS and comprised the ITBS group; the other 15 were healthy and comprised the control group. All participants underwent two gait trials, namely, before the first day of their running and after eight weeks, during which a force platform and a motion capture system collected biomechanical data. After running, the ITBS group exhibited greater anterior pelvic tilt and hip flexion angle than the control group. The ITBS group showed increased trunk inclination angle, whereas the control group demonstrated lower hip flexion, hip adduction angle and hip abductor moment than those at the beginning of running. Decreasing hip flexion, adduction angle and abductor moment may be a reasonable strategy to avoid the occurrence of ITBS. The occurrence of ITBS may be due to the lack of timely gait adjustment. Excessive trunk inclination and anterior pelvic tilt angle may be risks factor in the development of ITBS during running.

Hip and Ankle Kinematics in Noncontact Anterior Cruciate Ligament Injury Situations: Video Analysis Using Model-Based Image Matching

BACKGROUND

Detailed kinematic descriptions of real anterior cruciate ligament (ACL) injury situations are limited to the knee only.

PURPOSE

To describe hip and ankle kinematics as well as foot position relative to the center of mass (COM) in ACL injury situations through use of a model-based image-matching (MBIM) technique. The distance between the projection of the COM on the ground and the base of support (BOS) (COM_BOS) normalized to the femur length was also evaluated.

STUDY DESIGN

Descriptive laboratory study.

METHODS

Ten ACL injury video sequences from women's handball and basketball were analyzed. Hip and ankle joint kinematic values were obtained by use of MBIM.

RESULTS

The mean hip flexion angle was 51° (95% CI, 41° to 63°) at initial contact and remained constant over the next 40 milliseconds. The hip was internally rotated 29° (95% CI, 18° to 39°) at initial contact and remained unchanged for the next 40 milliseconds. All of the injured patients landed with a heel strike with a mean dorsiflexion angle of 2° (95% CI, -9° to 14°), before reaching a flatfooted position 20 milliseconds later. The foot position was anterior and lateral to the COM in all cases. However, none of the results showed larger COM_BOS than 1.2, which has been suggested as a criterion for ACL injury risk.

CONCLUSIONS

Hip kinematic values were consistent among the 10 ACL injury situations analyzed; the hip joint remained unchanged in a flexed and internally rotated position in the phase leading up to injury, suggesting that limited energy absorption took place at the hip. In all cases, the foot contacted the ground with the heel strike. However, relatively small COM_BOS distances were found, indicating that the anterior and lateral foot placement in ACL injury situations was not different from what can be expected in noninjury game situations.

Effect of a prosthetic foot with active ankle dorsiflexion and individualized training - a case study

Following a transfemoral amputation (TFA), numerous changes in movement patterns during gait can occur. Frontal plane hip and pelvis compensatory strategies are recognized among individuals with a TFA, some thought to aid in safe foot clearance during the swing phase of gait. The aim of this case study was to evaluate the effect of an active ankle dorsiflexion provided by a microprocessor-controlled prosthetic foot, as well as the effect of individualized training on these parameters. In this case study, a 42-year-old male underwent 3 D gait analysis. Data were captured for two conditions; with a microprocessor-controlled prosthetic foot with active/inactive ankle dorsiflexion, during two sessions; before and after 6 weeks of individualized training. The main outcomes analyzed were frontal plane pelvis and hip kinematics. Prior to training, pelvic lift decreased slightly, coupled with an increase in hip abduction, during gait with the active ankle dorsiflexion of a prosthetic foot, compared to inactive dorsiflexion. After the training period, the pelvic lift was further decreased and an increase in hip adduction was concurrently seen. The results of this case study indicate a positive effect of the active dorsiflexion of the prosthetic foot but highlight the need for specific training after prescription of a microprocessor prosthetic foot. Implications for rehabilitation Decreased compensatory changes seen in this case study indicate a positive effect of the active dorsiflexion of the prosthetic foot, especially after a 6-week training period. Individualized training should be aimed at helping the user utilizing the benefits of the active dorsiflexion of the microprocessor prosthetic foot, implementing exercises that improve gait quality, technical training for this specific foot, strength training and balance exercises.

Position-Specific Hip and Knee Kinematics in NCAA Football Athletes

BACKGROUND

Femoroacetabular impingement is a debilitating hip condition commonly affecting athletes playing American football. The condition is associated with reduced hip range of motion; however, little is known about the range-of-motion demands of football athletes. This knowledge is critical to effective management of this condition.

PURPOSE

To (1) develop a normative database of game-like hip and knee kinematics used by football athletes and (2) analyze kinematic data by playing position. The hypothesis was that kinematics would be similar between running backs and defensive backs and between wide receivers and quarterbacks, and that linemen would perform the activities with the most erect lower limb posture.

STUDY DESIGN

Descriptive laboratory study.

METHODS

Forty National Collegiate Athletic Association (NCAA) football athletes, representing 5 playing positions (quarterback, defensive back, running back, wide receiver, offensive lineman), executed game-like maneuvers while lower body kinematics were recorded via optical motion capture. Passive hip range of motion at 90° of hip flexion was assessed using a goniometer. Passive range of motion, athlete physical dimensions, hip function, and hip and knee rotations were submitted to 1-way analysis of variance to test for differences between playing positions. Correlations between maximal hip and knee kinematics and maximal hip kinematics and passive range of motion were also computed.

RESULTS

Hip and knee kinematics were similar across positions. Significant differences arose with linemen, who used lower maximal knee flexion (mean ± SD, 45.04° ± 7.27°) compared with running backs (61.20° ± 6.07°; P < .001) and wide receivers (54.67° ± 6.97°; P = .048) during the cut. No significant differences were found among positions for hip passive range of motion (overall means: 102° ± 15° [flexion]; 25° ± 9° [internal rotation]; 25° ± 8° [external rotation]). Several maximal hip measures were found to negatively correlate with maximal knee kinematics.

CONCLUSION

A normative database of hip and knee kinematics utilized by football athletes was developed. Position-specific analyses revealed that linemen use smaller joint motions when executing dynamic tasks but do not demonstrate passive range of motion deficits compared with other positions.

CLINICAL RELEVANCE

Knowledge of requisite game-like hip and knee ranges of motion is critical for developing goals for nonoperative or surgical recovery of hip and knee range of motion in the symptomatic athlete. These data help to identify playing positions that require remedial hip-related strength and conditioning protocols. Negative correlations between hip and knee kinematics indicated that constrained hip motion, as seen in linemen, could promote injurious motions at the knee.

In vitro analysis of peri-articular soft tissues passive constraining effect on hip kinematics and joint stability

PURPOSE

Aim of the study is to assess the contribution of peri-articular soft tissues to hip joint kinematics and their influence on hip stability.

METHODS

Four hemi-corpse specimens (3 males, average age 72 years) were studied using a custom navigation system. Hip kinematics (femoral head motion relative to the acetabulum and joint range of motion) were evaluated with the hip manually positioned in 36 different positions with (I) soft tissues intact, (II) after removal of the skin and muscles and (III) after partial capsulectomy. Each position was repeated 3 times in each state.

RESULTS

Excellent interclass correlation for each test was determined (ICC range, 0.84-0.96). Femoral head anatomical centre displacement relative to the acetabulum occurred in all 3 planes, even with all the soft tissue intact (average, 3.3 ± 2.8 mm lateral translation; 1.4 ± 1.8 mm posterior translation and 0.3 ± 1.5 mm distally). These translations increased as more soft tissue was removed, except medial-lateral displacement, with an average 4.6 ± 2.9 mm lateral translation, 0.7 ± 1.3 mm posterior translation and 1.5 ± 1.9 mm distal translation when partial capsulectomy was performed. Range of motion increased in all 3 planes with increasing removal of the soft tissues.

CONCLUSIONS

This study showed that femoral head anatomical centre displacement within the acetabulum occurs and increases with increasing removal of peri-articular soft tissues, confirming their influence on hip stability. Hip kinematics was also influenced by peri-articular soft tissues; specifically range of motion increases with increasing removal of those tissues. From clinicians' point of view, they have therefore to consider the influence of their surgeries on peri-articular soft tissues, since excessive translations may promote hip arthritis.