The purpose of this study is to clarify the effect of hip, knee, and ankle joint contractures on the joint angle and joint moment during standing posture using a mechanics simulation. A two-dimensional segment model (trunk, thighs, shanks, and feet) was created, and the standing postures for various hip, knee, and ankle joint angle configurations were generated (i.e. 743 types of standing postures). The hip, knee, and ankle joint contractures were reproduced by manipulating the joint stiffness, and optimal standing posture when the minimum value of the sum of muscle activities was obtained. When the hip joint contracture was developed during standing posture, the hip and knee flexion angle, and the hip and knee extension moment increased as well. When the knee joint contracture was developed during standing posture, the hip and knee flexion angle, ankle dorsiflexion angle, and the knee extension moment increased. When the ankle joint contracture was developed during standing posture, the hip flexion angle and the ankle plantarflexion angle increased and the knee joint was extended; the hip extension moment and knee flexion moment also increased. The findings of this study may help to improve abnormal standing posture through physical therapy.

INTRODUCTION: Fifteen to fifty percent of all sports injuries commonly occur in the knee joint. Active women are more susceptible to Patellofemoral Pain Syndrome (PFPS) than men. Aims: This study aims to associate the presentation of different movement compensations at the different body segments such as the hip, knee, and foot with the presence of PFPS among female collegiate football players at the University of Santo Tomas. METHODS: In this descriptive observational cross-sectional study, purposive sampling was used to recruit participants. A total of 11 participants were included. PFPS has a strong association with Anterior Knee Pain (AKP), and it was diagnosed using the Physical Examination questionnaire. With the use of dynamic and transitional assessments, namely overhead squat test (OST) and tuck jump test (TJT), movement patterns were observed using standardized data sheets and video analysis. RESULTS: Among those 11 female participants (mean age 19 ± 1.7 years old), 8 were diagnosed with PFPS and 3 were negative of PFPS. An association between different compensations and PFPS was sought using Fisher’s exact statistical tool. In the OST, compensations such as the foot turning out, foot flattening, knee directing inward and outward, lumbo-pelvic-hip complex patterns. In the TJT, PFPS was associated with three general compensations: foot placement, landing contact noise, and lower extremity valgus. CONCLUSION There was no direct association found between movement compensations and PFPS in dynamic and transitional assessments among female collegiate football players in this study. Although there are a few associations between different lower extremity movement compensations with PFPS. The majority of those with PFPS had knee out and LPHC compensations with the OST. With the TST, those with PFPS have positive foot placement compensations as compared to the majority of those without PFPS.

BACKGROUND: Muscular imbalance in the core and hip is one of the major risk factors associated with PFPS. There is evidence that decreased strength of the hip musculature is present in individuals with PFPS. This decrease in hip strength can also affect the stability of the core and further predisposes an athlete to injury. OBJECTIVES: This is a cross-sectional study that compares the hip muscle strength and core stability of collegiate football players with and without PFPS. METHODS: 25 participants (10 with PFPS and 15 without PFPS) participated in the study. Hip strength was measured using a digital handheld dynamometer. Core stability was assessed through the McGill Core Strength test and the 8-stage stability test. RESULTS: The hip adductors showed to be significantly weaker in those with PFPS as compared to those without PFPS ( p=0.040). No differences were found in the hip flexor (p=0.812), hip extensor (p=0.460) and abductors (p=0.126) strength while the core musculature showed that there is a statistically significant difference on the endurance of the lateral core musculature (p<0.001) and trunk flexors (p=0.027) between the two groups. CONCLUSION Football athletes without PFPS in this study demonstrated greater core stability and hip adductor muscle strength compared to those without PFPS.
Patellofemoral Pain Syndrome ; Lower Extremity ; Football