Dynamic knee valgus alignment influences impact attenuation in the lower extremity during the deceleration phase of a single-leg landing

Context: Excessive knee valgus on landing can cause anterior cruciate ligament injury. Therefore, knee valgus alignment may show characteristic energy absorption patterns during landings with lateral movement that impose greater impact forces on the knee joint compared with landings in other alignments. Objective: To investigate the energy absorption strategy in lower-extremities during side steps in females with knee valgus alignment. Design: Controlled laboratory study. Setting: University research laboratory. Participants: A total of 34 female college students participated in this experiment. Interventions: Participants performed single-leg drop vertical jump and side steps. All participants were divided into valgus (n = 13), neutral (n = 9), and varus (n = 12) groups according to knee position during landing in single-leg drop vertical jumps. Main Outcome Measures: Lower-extremity joint angles, moments, and negative works were calculated during landing in side steps, and 1-way analysis of variance and post hoc tests were used to determine between-group differences. Results: Negative works of hip extensors, knee abductors, and ankle plantar flexors during landing in side steps were significantly smaller in the valgus than in the varus group; however, negative work of the knee extensors was significantly greater in the valgus group than in varus group. Conclusions: The findings of this study indicated that landing with knee valgus induced the characteristic energy absorption strategy in the lower-extremity. Knee extensors contributed more to energy absorption when landing in knee valgus than in knee varus alignment. Learning to land in knee varus alignment might reduce the impact on the knee joint by increasing the energy absorption capacities of hip extensors, knee abductors, and ankle plantar flexors.

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The Relationship between Dynamic Knee Valgus and Lower Extremity Muscle Activity in Patients with Chronic Ankle Instability

Arsenal Augusta University’s Undergraduate Research Journal ◽

10.21633/issn.2380.5064/s.2021.04.01.10 ◽

2021 ◽

Vol 4 (1) ◽

pp. 10-10

Author(s):

Tammy Eboigbe ◽

Valerie Hogan

Keyword(s):

Lower Extremity ◽

Muscle Activity ◽

Ankle Instability ◽

Chronic Ankle Instability ◽

Knee Valgus ◽

Lower Extremity Muscle ◽

The Relationship

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Energy Absorption Strategies in the Lower Extremities during Double-Leg Landings in Knee Valgus Alignment

Applied Sciences ◽

10.3390/app10238742 ◽

2020 ◽

Vol 10 (23) ◽

pp. 8742

Author(s):

Akihiro Tamura ◽

Kiyokazu Akasaka ◽

Takahiro Otsudo

Keyword(s):

Energy Absorption ◽

Mechanical Load ◽

Three Dimensional ◽

Lower Extremities ◽

Mechanical Work ◽

Knee Valgus ◽

Landing Position ◽

Drop Jumps ◽

Analysis System ◽

Valgus Alignment

Landing with the knee in a valgus position may alter energy absorption strategies in the lower extremities and increase mechanical stress on the knee joint. We compared the energy absorption strategies in the lower extremities during valgus and varus landings. Seventeen females were divided into valgus and varus groups. Lower extremity kinetic data were obtained during drop jumps, using a three-dimensional motion analysis system. Negative mechanical work in the lower extremities were calculated during landing. The valgus group exhibited significantly more negative mechanical work at the knee, and less negative mechanical work at the hip, compared with the varus group. However, there was no difference in the negative mechanical work at the ankle between the two groups. Findings suggest that an increased valgus landing reduces the contribution of the hip to energy absorption and is associated with a reciprocal increased contribution by the knee. Hence a knee valgus landing position may be a key biomechanical factor that increases energy absorption in the knee, thereby increasing the risk of injury. Results further indicate that this can be prevented by adopting a knee varus position on landing, which facilitates absorption of the mechanical load at the hip, rather than at the knee.

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Effects of Various Midsole Densities of Basketball Shoes on Impact Attenuation during Landing Activities

Journal of Applied Biomechanics ◽

10.1123/jab.21.1.3 ◽

2005 ◽

Vol 21 (1) ◽

pp. 3-17 ◽

Cited By ~ 35

Author(s):

Songning Zhang ◽

Kurt Clowers ◽

Charles Kohstall ◽

Yeon-Joo Yu

Keyword(s):

Lower Extremity ◽

Repeated Measures ◽

Impact Force ◽

Shock Attenuation ◽

Kinematic Data ◽

Repeated Measures Analysis ◽

Impact Attenuation ◽

Reaction Forces ◽

Lower Extremity Biomechanics ◽

Evidence Of Impact

The purpose of this study was to examine effects of shoe midsole densities and mechanical demands (landing heights) on impact shock attenuation and lower extremity biomechanics during a landing activity. Nine healthy male college athletes performed 5 trials of step-off landing in each of 9 test conditions, i.e., a combination of landings in shoes of 3 midsole densities (soft, normal, hard) from each of 3 landing potential energy (PE) levels (low, median, high). Ground reaction forces (GRF), accelerations (ACC) of the tibia and forehead, and sagittal kinematic data were sampled simultaneously. A 3 × 3 two-way (surface × height) repeated-measures analysis of variance (ANOVA) was performed on selected kinematic, ACC, and GRF variables; a 3 × 3 × 3 three-way (surface × height × joint) ANOVA was performed on variables related to eccentric muscular work. The GRF results showed that the forefoot peak GRF in the normal and hard midsoles was significantly greater than the soft midsole at the low and median PEs. Rearfoot peak GRF was significantly greater for the hard midsole than for the soft and normal midsoles at the median and high PEs, respectively. The peak head and tibia peak ACC were also attenuated in similar fashion. Kinematic variables did not vary significantly across different midsoles, nor did energy absorbed through lower extremity extensors in response to the increased shoe stiffness. Knee joint extensors were shown to be dominant in attenuating the forefoot impact force across the landing heights. The results showed limited evidence of impact-attenuating benefits of the soft midsole in the basketball shoes.

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Factors influencing knee valgus alignment in Crowe type IV hip dysplasia after total hip arthroplasty

Journal of Orthopaedics and Traumatology ◽

10.1186/s10195-021-00601-y ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Jing-yang Sun ◽

Hai-yang Ma ◽

Jun-min Shen ◽

Yin-qiao Du ◽

Yu Dong ◽

...

Keyword(s):

Total Hip Arthroplasty ◽

Hip Arthroplasty ◽

Hip Dysplasia ◽

Limb Length ◽

Knee Valgus ◽

Total Hip ◽

Type Iv ◽

Factors Influencing ◽

Postoperative Knee ◽

Valgus Alignment

Abstract Background Valgus deformity of the knee remains a complaint after total hip arthroplasty (THA) among some patients with Crowe type IV hip dysplasia. We aimed to identify the knee alignment in these patients before and after surgery, and to explore the factors contributing to postoperative knee valgus alignment. Materials and methods We retrospectively reviewed a series of Crowe type IV patients who received THA between February 2010 and May 2019 in our hospital. The patients’ medical data were collected from the hospital information system. On both preoperative and postoperative full limb length standing radiographs, the following parameters were measured: hip–knee–ankle angle (HKA), mechanical lateral distal femoral angle (mLDFA), medial proximal tibial angle, anatomical tibiofemoral angle, anatomical lateral distal femoral angle, femoral neck-shaft angle, pelvic obliquity, limb length, height and lateral distance of hip center, and femoral offset. Univariate and multivariate binary logistic regression were used to identify the factors influencing postoperative knee valgus alignment. Results A total of 64 Crowe type IV patients (87 hips) were included in the study. Overall, HKA improved from 176.54 ± 3.52° preoperatively to 179.45 ± 4.31° at the last follow-up. Those hips were subdivided into non-valgus group (≥ 177.0°, n = 65) and valgus group (< 177.0°, n = 22) according to postoperative HKA. Only postoperative mLDFA was a significant factor in the multivariate regression model. Conclusions The postoperative mLDFA is a major factor related to knee valgus alignment after THA, which combines the preoperative anatomy and surgical reconstruction. Other factors previously published were found to have no significance. Level of evidence III.

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