The Kinetic Relationship between Sitting & Standing Posture & Pelvic Inclination. A. Stephens, S. Munir, S. Shah, W.L Walter The Specialist Orthopaedic Group, Sydney Australia ISOC Mexico City 2014
Transcript
Slide 1
The Kinetic Relationship between Sitting & Standing Posture
& Pelvic Inclination. A. Stephens, S. Munir, S. Shah, W.L
Walter The Specialist Orthopaedic Group, Sydney Australia ISOC
Mexico City 2014
Slide 2
I declare that in the past three years I have: held shares in:
N/A received royalties from: Stryker done consulting work for:
Stryker/ Ceramtec/ Depuy/ Matortho given paid presentations for:
Ceramtec received institutional support from: Depuy, Stryker
Signed: A/P Bill Walter
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Chair rising
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dislocation
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loading patch
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Consequences of edge loading
Ceramic-ceramicMetal-metalpolyethylene Squeaking +++- Wear ++++++++
Rim breakage +-+ Late dislocation --++
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Edge loading
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Case 1: High Metal Wear Max depth 90 m, Volume 66 mm 3
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Fatigue failures of retrieved highly crosslinked UHMWPE
acetabular liners Furmanski, Pruitt et al., AAOS 2008
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56 Trident cups 28mm MoP 2 to 5 years Linear head penetration
rate from AP X-ray 40% increase in linear poly wear in cups >
45deg inclination
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Study Design Measurements: Clinical Hip flexion /Fixed flexion
Hip flexion on XR Anterior pelvic plane on lateral radiographs
Lower lumbar lordosis cobb angle Demographics N=60 30 male / 30
female Mean Age 63.2 (37 93)years Hip osteoarthritis Exclusion
criteria Previous fractures Revision THA Long spinal fusion
Patients without preoperative sitting and standing films
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Posterior tilt No tilt Anterior tilt
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Cobb angle change
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Introduction Safe Zone of Lewinnek 40 inclination/ 20
anteversion of cup Individual differences to pelvic tilt in sitting
and standing Influence acetabular version Aim To describe the
influence of sitting and standing posture on sagittal pelvic
inclination
CONCLUSION Pelvic orientation changes from standing to sitting
Stiff hips tend to tilt the pelvis posteriorly from standing to
sitting The degree of tilt may be measured on lateral sitting and
standing films This has implications for cup version during total
hip arthroplasty Hip flexion Hip flexion range degree Anterior tilt
Posterior tilt
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Next questions. What happens after hip replacement? Does the
pelvic motion change?