How Subtalar Kinematics Affects Knee Laxity in Soccer Players After Anterior Cruciate Ligament Injury?

Purpose The goal of the current study was to ascertain whether there is an association between foot pronation and anterior cruciate ligament (ACL) injury in a group of elite professional soccer players. Methods Two groups of soccer players were studied, all of whom played in the Greek Super League. The ACL group included players who had suffered an ACL injury in the last 2 years. The non-ACL group was composed of players who had never suffered an ACL injury. We used a 3D baropodometric laser scanner to measure pronation or overpronation (navicular drop phenomenon) of the subtalar joint and how this affects the subtalar joint while standing. We assessed ACL laxity using the Genourob Rotab. Results ACL-injured patients, regardless of the mechanism of injury, exhibited greater navicular drop values than a randomly selected group of subjects with no history of ACL injury. Conclusion Greater knee joint laxity and subtalar pronation may be associated with an increased risk of ACL injury. Pronation of the foot appears to be a risk factor for ACL injury. These findings should be integrated into future studies to better define how neuromuscular control related to lower extremity biomechanics is associated with ACL injury.

Defining excessive, over, or hyper-pronation: A quandary.

Abnormal-pronation, excessive-pronation, over-pronation, or hyper-pronation, are terms with a long historical use in both medical and research terminology pertaining to an abnormal movement of the foot. These terms are commonly used as a potential kinematic aetiology to explain the occurrence of multiple lower limb and foot pathologies. Yet despite this widespread use there is no clear definition to explain what the terms abnormal, excess, over, or hyper-pronation, mean. Without a strict definition the use of these terms as a patho-mechanical explanation of injuries, leaves a distinct lack of clarity and is meaningless in regards to being able to distinguish what movement may need clinical intervention. It is unlikely that hyper-pronation can be given a quantitative scale because individual anatomy and activity changes the necessary range of pronation within the foot. This paper attempts to give hyper-pronationa philosophically justifiable definition so that the term may be used in a more precise manner and avoid the confusion that presently exists clinically as well as in research literature.

The effect of foot overpronation on Achilles tendon blood supply in healthy male subjects.

The purpose of this study was to investigate Achilles tendon blood flow in individuals with overpronated feet during non-weight- and weight-bearing positions. Achilles tendon blood flow was measured by means of the pulsatility index (PI) and the resistance index (RI) in 15 male individuals with overpronated feet and 15 counterparts with normal feet, using power Doppler ultrasonography (PDI). Achilles tendon ultrasonographic (US) assessment was performed at its musculo-tendinous junction (MTJ), mid-tendon (MT), and osseotendinous junction (OTJ) at a non-weight-bearing relaxed position (RP) and during two-leg stance (TLS) and one-leg upright stance (OLS). PI and RI indices were significantly greater in individuals with overpronated feet compared to individuals with normal feet at the OTJ in OLS position (P < 0.01), and at MT in both TLS (P < 0.001) and OLS positions (P < 0.001). All individuals demonstrated also greater PI and RI indices at MT followed by the OTJ and MTJ in all positions (P < 0.001), and in OLS compared to TLS and the RP at the OTJ (P < 0.01) as well as at MT and MTJ (P < 0.001). The findings of the present study suggest that foot overpronation may affect Achilles tendon blood flow, particularly at mid-tendon, thus enhancing the possibility for injury.

Foot Overpronation: Influence on Body Alignment and Managements (review) / 中国康复理论与实践

@#The foot overpronation is termed as pronation persisting more than 25%of stance phase in a walking cycle, which may re-sult from some antenatal or postnatal conditions. Overpronation would lead to abnormal alignment of ankle, knee, pelvis and spine, and re-sult in a set of syndromes of chronic pain. The Navicular Drop Test and the Foot Posture Index are often used as the assessment tools, how-ever, there are several empirical ways for clinic. Foot orthoses, special shoes, taping and training of muscle strength are effective on overpro-nation as well as chronic pain.

Don't get caught flat footed - how over-pronation may just be a dysfunctional model.

For many years there has been a long-held clinical belief that a flat or over-pronating foot should be supported; yet in every other part of the body it has long been recognised that use of support (if at all) should generally be limited to acute rehabilitation. Why should the foot be any different? To support a biological structure, in the long term, is to weaken it. Panjabi's model of joint stability offers insight into why the idea of arch support, as well-intentioned as it may have been, may be a dysfunctional model. A test (and conditioning exercise) is presented which appears to support the notion that there is no such thing as a flat foot; only a de-conditioned foot.