Mechanical advantage and joint function of the lower limb during hopping at different frequencies

This article described the clinical examination of the lower extremity during a pre-participation screening in regard of sports ability, presence of injuries and musculoskeletal disorders as well as predisposing risk factors for injuries and prevention. It divided into global static and dynamic testing but also isolated analysis of joint function.

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Fibrous hip ankylosis in adolescents: non-standard approach to treatment (clinical observation)

Pediatric Traumatology Orthopaedics and Reconstructive Surgery ◽

10.17816/ptors6370-77 ◽

2018 ◽

Vol 6 (3) ◽

pp. 70-77

Author(s):

Oleg V. Kozhevnikov ◽

Svetlana E. Kralina ◽

Alexey V. Ivanov

Keyword(s):

Hip Joint ◽

Joint Replacement ◽

Lower Limb ◽

Clinical Case ◽

Clinical Observation ◽

Childhood And Adolescence ◽

Joint Function ◽

Treatment Results ◽

Modern Treatment ◽

Post Infectious

The development of secondary deforming coxarthrosis in childhood and adolescence, as a rule, is accompanied by the formation of a pronounced deformity of the hip joint, up to ankylosis, which significantly limits the function of the lower limb and leads to early disability. In most patients, hip ankylosis develops in a vicious position with the resulting flexion-intracavity installation of the lower limb. If such a condition is encountered in childhood and adolescence, treatment currently remains debatable. Various methods are used, ranging from arthroplastic organ-preserving interventions and corrective osteotomies to joint replacement. In this report, we present a clinical case of children treated with post-infectious secondary deforming coxarthrosis with fibrous ankylosis of the hip joint in a vicious position. We applied a coherent combination of modern treatment methods: distraction in the apparatus, arthroscopy, intra-articular injections, physiotherapy, and other rehabilitation. The treatment results were evaluated over a two-year period. In this case, the rational use of a consistent set of remedial measures helped to improve joint function, socialize the patient, and postpone surgery for joint replacement for at least 2 years.

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Design of Lower Limb Prosthesis Transverse Plane Adaptor With Variable Stiffness

Journal of Medical Devices ◽

10.1115/1.4030505 ◽

2015 ◽

Vol 9 (3) ◽

Cited By ~ 10

Author(s):

Corey Pew ◽

Glenn K. Klute

Keyword(s):

Lower Limb ◽

Variable Stiffness ◽

Plane Motion ◽

Transverse Plane ◽

Torsional Stiffness ◽

Mechanical Advantage ◽

Lower Limb Prosthesis ◽

Activity Dependent ◽

Limb Prosthesis ◽

Lower Limb Amputees

A lower limb prosthesis is able to restore mobility to patients who have lost a limb; however, no current replacement is as moveable and adaptable as the limb that was lost. Therefore, all amputees suffer from a reduction in function at some level. Movement in the transverse plane of a lower limb prosthesis is often negated in a traditional prosthesis, and those devices that do allow for transverse plane motion are set to a single, fixed stiffness, and incapable of adapting to the varying activities of the user. A prototype device has been created that allows for varying stiffness in the transverse plane of a lower limb prosthesis. The variable stiffness torsion adapter (VSTA) functions by way of a movable pivot lever arm that can actively modify the mechanical advantage between the outer housing and the internal spring. The motion of the pivot is perpendicular to the external torque allowing for low power adjustments of the stiffness. Bench tests were performed and demonstrate the ability of the VSTA to vary torsional stiffness between 0.12 and 0.91 N m/deg over a ±30 deg rotational range of motion. The device also includes a mode for fully locked operation. The VSTA may improve the mobility of lower limb amputees by allowing for activity-dependent transverse plane stiffness.

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