Force and motion of the child's hip during the gait cycle

George T Rab

Research output: Contribution to journalArticle

Abstract

In an effect to better understand the transmission of force across the child's hip, the author performed a theoretical analysis using a hemispherical model of the femoral epiphysis. The acetabulum was modelled as an external, concentric, 3/4 hemispherical shell, and both were oriented in weight-bearing position from X-ray and cadaver studies. Using literature data, the epiphysis was allowed to rotate through the gait cycle, and incremental 3-dimensional force data were superimposed on the moving femoral head. It was found that epiphyseal shear stress was relatively low (> 1.5 body weight), even when compressive stress was high (heel strike and mid-stance), because of the unique orientation of the epiphyseal plate. Acetabular 'containment' of the anterior and lateral femoral epiphysis was best at heel strike, but was quite poor during stance phase. Theoretical reorientation of either acetabulum or femoral head, as with innominate or femoral osteotomy, failed to achieve satisfactory coverage during both these high-stress phases of gait.

Original languageEnglish (US)
Pages (from-to)626
Number of pages1
JournalJournal of Biomechanics
Volume12
Issue number8
StatePublished - 1979

Fingerprint

Bearings (structural)
Thigh
Compressive stress
Gait
Hip
Shear stress
Epiphyses
X rays
Acetabulum
Heel
Growth Plate
Weight-Bearing
Osteotomy
Cadaver
Body Weight
X-Rays

ASJC Scopus subject areas

  • Orthopedics and Sports Medicine

Cite this

Force and motion of the child's hip during the gait cycle. / Rab, George T.

In: Journal of Biomechanics, Vol. 12, No. 8, 1979, p. 626.

Research output: Contribution to journalArticle

Rab, George T. / Force and motion of the child's hip during the gait cycle. In: Journal of Biomechanics. 1979 ; Vol. 12, No. 8. pp. 626.
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