Predictive value of bone mineral density and Singh Index for the in vitro mechanical properties of cancellous bone in the femoral head

The bone mineral density (BMD) of retrieved cancellous bone samples is compared to the BMD measuredin vivoin the respective osteoarthritic patients. Furthermore, mechanical properties, in terms of structural modulus (Es) and ultimate compression strength (σmax) of the bone samples, are correlated to BMD data. Human femoral heads were retrieved from 13 osteoarthritic patients undergoing total hip replacement. Subsequently, the BMD of each bone sample was analysed using dual energy X-ray absorptiometry (DXA) as well as ashing. Furthermore, BMDs of the proximal femur were analysed preoperatively in the respective patients by DXA. BMDs of the femoral neck and head showed a wide variation, from1016±166 mg/cm2to1376±404 mg/cm2. BMDs of the bone samples measured by DXA and ashing yielded values of315±199 mg/cm2and347±113 mg/cm3, respectively.Esandσmaxamounted to232±151 N/mm2and6.4±3.7 N/mm2. Significant correlation was found between the DXA and ashing data on the bone samples and the DXA data from the patients at the femoral head (r=0.85and 0.79, resp.).Escorrelated significantly with BMD in the patients and bone samples as well as the ashing data (r=0.79,r=0.82, andr=0.8, resp.).

Download Full-text

Local Variation in Femoral Neck Cortical Bone: In Vitro Measured Bone Mineral Density, Geometry and Mechanical Properties

Journal of Clinical Densitometry ◽

10.1016/j.jocd.2015.10.003 ◽

2017 ◽

Vol 20 (2) ◽

pp. 205-215 ◽

Cited By ~ 2

Author(s):

Louise V. Coutts ◽

Thomas Jenkins ◽

Richard O.C. Oreffo ◽

Doug G. Dunlop ◽

Cyrus Cooper ◽

...

Keyword(s):

Mechanical Properties ◽

Bone Mineral Density ◽

Femoral Neck ◽

Cortical Bone ◽

Bone Mineral ◽

Local Variation ◽

Mineral Density

Download Full-text

Can the Bone Mineral Density of the Non-fractured Contralateral Hip Predict Medial Migration of Helical Blade-type Lag Screws in Osteoporotic Hip Fractures?

10.21203/rs.3.rs-94889/v1 ◽

2020 ◽

Author(s):

Suenghwan Jo ◽

Hyun Jun Lee ◽

Sang Hong Lee ◽

Je Hong Ryu ◽

Ba Rom Kim ◽

...

Keyword(s):

Mechanical Properties ◽

Bone Mineral Density ◽

Femoral Head ◽

Bone Mineral ◽

Mineral Density ◽

Lag Screw ◽

Medial Migration ◽

Femoral Heads ◽

Helical Blade ◽

The Mean

Abstract Background: In this study, we performed a biomechanical tests on the osteoporotic femoral heads to validate whether the bone mineral density (BMD) measured at the non-fractured contralateral hip can predict the BMD and potential medial migration of helical blade-type lag screws on the fractured femoral head.Methods: Twenty-four osteoporotic femoral heads were retrieved from patients with femoral neck fracture undergoing hip arthroplasty. The patients had their BMD measured from the contralateral hip using dual-energy X-ray absorptiometry prior to surgery. The BMD of the retrieved femoral heads was measured using micro-computed tomography. The mechanical properties for the medial migration of lag screw were measured by performing an uniaxial compression test on the femoral head using a helical blade-type lag screw. Statistical analysis was performed to determine the correlation among the BMDs of the non-fractured contralateral hip and the retrieved femoral head and the mechanical properties of the fractured femoral head.Results: The mean BMD of the contralateral hip was 0.60±0.14 g/cm2 in the neck region and 0.63±0.15 g/cm2 in the total proximal femur. The mean BMD of the fractured femoral head was 463.3±48.05 mg HA/cm3. The mechanical properties of the fractured femoral head were measured to be 0.92 kN for the maximum compressive load and 14.50±5.48 kN for the accumulated compression load. In the analysis of the correlation among the parameters, we found no correlation between the BMD of the non-fractured contralateral hip and the mechanical properties of the fractured femoral head. In addition, we observed no correlation between the BMD of the fractured femoral head and that of the contralateral hip.Conclusions: Our results indicate that the BMD of the contralateral hip does not reflect the BMD or the mechanical properties of the fractured femoral head. Therefore, helical blade-type lag screw migration may not be predicted from the BMD of the non-fractured contralateral hip.

Download Full-text

Comparison of in Vitro Young and Old Lumbar Vertebrae of Ewes Related to Bone Density and Compression Strength

Modern Applied Science ◽

10.5539/mas.v11n4p65 ◽

2017 ◽

Vol 11 (4) ◽

pp. 65 ◽

Cited By ~ 1

Author(s):

Sahar Ahmed Abdalbary ◽

Sherif Mamdouh Amr

Keyword(s):

Mechanical Properties ◽

Bone Mineral Density ◽

Animal Model ◽

Bone Mineral ◽

Lumbar Vertebrae ◽

Compressive Force ◽

Fixation Strength ◽

Mineral Density ◽

Orthopedic Device

An animal model (the ewe) was used to study the mechanical properties of lumbar vertebrae and to compare these properties with the bone mineral density. We measured the bone mineral density for lumbar vertebrae of 10 ewes for L2 & L5 for5 young ewes mean age 2 years and 5 old ewes mean age 8 years old. Compression test was conducted on ewes lumbar vertebrae L2 & l5 for young ewes and old ewes.There was significance differences between both group related to bone mineral density , compressive force , and young’s modulus. There was strong correlation between the mechanical properties and bone mineral density.Bone mineral density correlated with the mechanical properties and it is not surprising that an orthopedic device used with poorly mineralized bone can have lower mechanical fixation strength than the same device with well-mineralized bone.

Download Full-text

Periarticular cancellous bone changes following anterior cruciate ligament injury

Journal of Applied Physiology ◽

10.1152/jappl.2001.91.1.336 ◽

2001 ◽

Vol 91 (1) ◽

pp. 336-342 ◽

Cited By ~ 22

Author(s):

Gregory R. Wohl ◽

Roxane C. Shymkiw ◽

John R. Matyas ◽

Reinhard Kloiber ◽

Ronald F. Zernicke

Keyword(s):

Mechanical Properties ◽

Bone Mineral Density ◽

Anterior Cruciate Ligament ◽

Articular Cartilage ◽

Bone Mineral ◽

Cancellous Bone ◽

Cruciate Ligament ◽

Mineral Density ◽

Bone Changes ◽

Anterior Cruciate

To understand more fully the early bone changes in an experimental model of osteoarthrosis, we quantified periarticular bone mineral density and bone mechanical properties in anterior cruciate ligament transected (ACLX) knee joints (4, 10, 32, and 39 wk post-ACLX) compared with contralateral joints and unoperated normal joints of skeletally mature animals. Maximal stress and energy were significantly reduced in ACLX cancellous bone from the medial femoral condyles at 4 wk postinjury. All mechanical properties (e.g., yield stress and elastic modulus) declined after 4 wk and were significantly reduced at 10 wk. ACLX bone mineral density was significantly reduced at all measured time points. Ash content was significantly reduced at 10 and 32 wk. Changes in the lateral condyles were similar but less pronounced than in the medial condyles. These bony changes accompanied the earliest articular cartilage molecular changes and preceded changes in the articular cartilage gross morphology. We suggest that these early changes in bone mechanical behavior contribute to the progression of osteoarthrosis and pathogenic changes in the joint.

Download Full-text