Limits...
Improvement of trochanteric bone quality in an osteoporosis model after short-term treatment with parathyroid hormone: a new mechanical test for trochanteric region of rat femur.

Tezval M, Stuermer EK, Sehmisch S, Rack T, Stary A, Stebener M, Konietschke F, Stuermer KM - Osteoporos Int (2009)

Bottom Line: We investigated the short-term effects of parathyroid hormone (PTH) and estrogen (E) on the strength of the rat trochanteric region in a new mechanical test.Animals of the PTH group demonstrated a significantly improved trabecular bone structure and area (75.67%) in comparison to the E (61.04%) and C (57.18%) groups.Our results show that the short-term antiosteoporotic effects of PTH are in the trochanteric region of ovariectomized rat superior to E.

View Article: PubMed Central - PubMed

Affiliation: Department of Trauma and Reconstructive Surgery, Georg-August-University of Goettingen, Goettingen, Germany. mtezval@med.uni-goettingen.de

ABSTRACT

Unlabelled: We have examined the changes induced in the trochanteric region of femur of ovariectomized rat after administration of estradiol and parathyroid hormone. We have developed a reproducible biomechanical test and produced trochanteric fractures to evaluate stiffness and strength of this region in addition to histomorphometry.

Introduction: We investigated the short-term effects of parathyroid hormone (PTH) and estrogen (E) on the strength of the rat trochanteric region in a new mechanical test.

Methods: Forty-four 3-month-old female Sprague-Dawley rats were ovariectomized and 8 weeks later treated with soy-free diet (C), daily applications of orally supplied E (0.5 mg/kg food) or subcutaneously injected PTH (0.014 mg/kg), for 5 weeks, and an additional untreated group was added as sham-operated. The femurs were examined for biomechanical and histomorphometric changes.

Results: Our new mechanical test was validated in a right-left comparison. The PTH treatment induced significantly superior biomechanical results (F (max) = 225.3 N, stiffness = 314.9 N/mm) compared to E (F (max) = 182.9 N, stiffness = 237.2 N/mm), C (F (max) = 166.03 N, stiffness = 235.56 N/mm), and sham (F (max) = 192.1 N, stiffness = 267.2 N/mm). Animals of the PTH group demonstrated a significantly improved trabecular bone structure and area (75.67%) in comparison to the E (61.04%) and C (57.18%) groups.

Conclusion: Our new biomechanical test is valid and produces trochanteric fracture. Our results show that the short-term antiosteoporotic effects of PTH are in the trochanteric region of ovariectomized rat superior to E.

Show MeSH

Related in: MedlinePlus

a–c The new breaking test is designed to produce trochanteric fractures for studying of biomechanical strength of trochanteric region of rat femur (here femur of Sprague–Dawley rat). The femoral head was fixed in a 4-mm deepening on the other end of the system. The femoral shaft was horizontal between two metallic movable rolling cylinders. The distal end of the femur was in contact with the aluminum plate without any rigidity. The force was applied with a ZWICK-testing machine, type 145660 Z020/TND (Zwick/Roell, Ulm, Germany)
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC2801842&req=5

Fig1: a–c The new breaking test is designed to produce trochanteric fractures for studying of biomechanical strength of trochanteric region of rat femur (here femur of Sprague–Dawley rat). The femoral head was fixed in a 4-mm deepening on the other end of the system. The femoral shaft was horizontal between two metallic movable rolling cylinders. The distal end of the femur was in contact with the aluminum plate without any rigidity. The force was applied with a ZWICK-testing machine, type 145660 Z020/TND (Zwick/Roell, Ulm, Germany)

Mentions: A novel mechanical loading configuration was developed to measure the strength of the trochanteric region of the femur, according to the design of one of the authors (K.M. Stuermer). The left and right femurs of non-OVX rats were tested in a direction vertical to the greater trochanter. The femoral head was fixed in a 4 mm deepening at one end of the system, while the femoral shaft was horizontally positioned between two metallic movable rolling cylinders. The distal end of the femur was in contact with the aluminum plate without any rigidity. The lesser trochanter did not come into contact with the aluminum plate at all because of a groove made to allow for free movement. The angle between the femoral shaft and the horizontal line was nearly 0°. Force was applied vertically to the greater trochanter using a roller stamp (Fig. 1a–c).Fig. 1


Improvement of trochanteric bone quality in an osteoporosis model after short-term treatment with parathyroid hormone: a new mechanical test for trochanteric region of rat femur.

Tezval M, Stuermer EK, Sehmisch S, Rack T, Stary A, Stebener M, Konietschke F, Stuermer KM - Osteoporos Int (2009)

a–c The new breaking test is designed to produce trochanteric fractures for studying of biomechanical strength of trochanteric region of rat femur (here femur of Sprague–Dawley rat). The femoral head was fixed in a 4-mm deepening on the other end of the system. The femoral shaft was horizontal between two metallic movable rolling cylinders. The distal end of the femur was in contact with the aluminum plate without any rigidity. The force was applied with a ZWICK-testing machine, type 145660 Z020/TND (Zwick/Roell, Ulm, Germany)
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2801842&req=5

Fig1: a–c The new breaking test is designed to produce trochanteric fractures for studying of biomechanical strength of trochanteric region of rat femur (here femur of Sprague–Dawley rat). The femoral head was fixed in a 4-mm deepening on the other end of the system. The femoral shaft was horizontal between two metallic movable rolling cylinders. The distal end of the femur was in contact with the aluminum plate without any rigidity. The force was applied with a ZWICK-testing machine, type 145660 Z020/TND (Zwick/Roell, Ulm, Germany)
Mentions: A novel mechanical loading configuration was developed to measure the strength of the trochanteric region of the femur, according to the design of one of the authors (K.M. Stuermer). The left and right femurs of non-OVX rats were tested in a direction vertical to the greater trochanter. The femoral head was fixed in a 4 mm deepening at one end of the system, while the femoral shaft was horizontally positioned between two metallic movable rolling cylinders. The distal end of the femur was in contact with the aluminum plate without any rigidity. The lesser trochanter did not come into contact with the aluminum plate at all because of a groove made to allow for free movement. The angle between the femoral shaft and the horizontal line was nearly 0°. Force was applied vertically to the greater trochanter using a roller stamp (Fig. 1a–c).Fig. 1

Bottom Line: We investigated the short-term effects of parathyroid hormone (PTH) and estrogen (E) on the strength of the rat trochanteric region in a new mechanical test.Animals of the PTH group demonstrated a significantly improved trabecular bone structure and area (75.67%) in comparison to the E (61.04%) and C (57.18%) groups.Our results show that the short-term antiosteoporotic effects of PTH are in the trochanteric region of ovariectomized rat superior to E.

View Article: PubMed Central - PubMed

Affiliation: Department of Trauma and Reconstructive Surgery, Georg-August-University of Goettingen, Goettingen, Germany. mtezval@med.uni-goettingen.de

ABSTRACT

Unlabelled: We have examined the changes induced in the trochanteric region of femur of ovariectomized rat after administration of estradiol and parathyroid hormone. We have developed a reproducible biomechanical test and produced trochanteric fractures to evaluate stiffness and strength of this region in addition to histomorphometry.

Introduction: We investigated the short-term effects of parathyroid hormone (PTH) and estrogen (E) on the strength of the rat trochanteric region in a new mechanical test.

Methods: Forty-four 3-month-old female Sprague-Dawley rats were ovariectomized and 8 weeks later treated with soy-free diet (C), daily applications of orally supplied E (0.5 mg/kg food) or subcutaneously injected PTH (0.014 mg/kg), for 5 weeks, and an additional untreated group was added as sham-operated. The femurs were examined for biomechanical and histomorphometric changes.

Results: Our new mechanical test was validated in a right-left comparison. The PTH treatment induced significantly superior biomechanical results (F (max) = 225.3 N, stiffness = 314.9 N/mm) compared to E (F (max) = 182.9 N, stiffness = 237.2 N/mm), C (F (max) = 166.03 N, stiffness = 235.56 N/mm), and sham (F (max) = 192.1 N, stiffness = 267.2 N/mm). Animals of the PTH group demonstrated a significantly improved trabecular bone structure and area (75.67%) in comparison to the E (61.04%) and C (57.18%) groups.

Conclusion: Our new biomechanical test is valid and produces trochanteric fracture. Our results show that the short-term antiosteoporotic effects of PTH are in the trochanteric region of ovariectomized rat superior to E.

Show MeSH
Related in: MedlinePlus