Post by warsaw on Dec 21, 2015 10:41:45 GMT -9
Some basic information :
EAR ATTACKS
(Copyright © 2001 by Steven P. French, M.D.)
The following is the text for the 43rd chapter in the Fourth Edition of Wilderness
Medicine, edited by Paul S. Auerbach, published by Mosby in 2001
en.wikipedia.org/wiki/Paul_Auerbach
BEAR-INDUCED INJURIES
Bear-inflicted injuries range from minor, treated on an outpatient basis, to
complex, requiring hospitalization and surgery, typically resulting in significant cosmetic
and functional disability. In this regard, bear attacks are similar to most other animal
attacks, particularly those inflicted by large animals.
The character of such injuries is determined in part by the three main sources:
teeth, claws, and paws. The teeth of bears, especially the canines, are large and sturdy.
Although the teeth are not particularly sharp, the power of the jaw muscles allows the
teeth to penetrate deep into soft tissues and to fracture facial bones and bones of the hand
and forearm with ease. The trauma characteristically results from punctures, with
shearing, tearing, and crushing forces (Figure 43-20).
The claws are another important source of trauma. Although the claws on the
front pads can be as long as human fingers, they are not particularly sharp on grizzlies
and polar bears. The bear’s shoulders, however, provide the force and speed that allows
claws to cause significant soft tissue damage in a scraping maneuver that results in deep,
parallel gashes. Because black bear claws are sharper and more curved, the cuts tend to
have sharper, less ragged edges.
The bear paw is capable of delivering a powerful force, resulting in significant
blunt trauma, particularly to the head and neck, ribcage, and abdominal cavity, especially
solid organ rupture. Therefore victims of bear attacks should be evaluated for occult
blunt trauma.
ORIGINAL PAPER
Large carnivore attacks on hominins during the Pleistocene:a forensic approach with a Neanderthal example
Edgard Camarós
www.academia.edu/12436456/Large_carnivore_attacks_on_hominins_during_the_Pleistocene_A_forensic_approach_with_a_Neanderthal_example
"...The present observation of a total of 45 forensic cases iscommensurate with this known attack pattern of bears.Figure 2a shows that within the 38 case studies with bone modifications, the main bone damage is located in the head zone(skullandmandible)and upper limbs(clavicle,humerus,radius, ulna, metacarpals, and hand phalanges). Bears tend toattack the victims head, causing wounds and fractures in that zone, and humans react by protecting themselves with their arms, causing damage in that region. Long-bone diaphyseal linear, comminuted, and segmental fractures in the upper limb are not rare,and finger amputation is also common(Dharetal.2008). All these bony injuries are frequently associated with general soft-tissue wounds (Fig. 2b), as observed in other cases (Rasool et al. 2010). Therefore, bone modification after a bear attack would appear to occur in the body areas where other general non-bony wounds are inflicted by the animal..."
www.academia.edu/12436456/Large_carnivore_attacks_on_hominins_during_the_Pleistocene_A_forensic_approach_with_a_Neanderthal_example
Unfortunately, I don't have access to this paper,but ....
Grizzly bear (Ursus arctos horribilis) locomotion: gaits and ground reaction forces
Catherine L. Shine, Skylar Penberthy, Charles T. Robbins, O. Lynne Nelson, Craig P. McGowan
ABSTRACT
Locomotion of plantigrade generalists has been relatively little studied compared with more specialised postures even though plantigrady is ancestral among quadrupeds. Bears (Ursidae) are a representative family for plantigrade carnivorans, they have the majority of the morphological characteristics identified for plantigrade species, and they have the full range of generalist behaviours. This study compared the locomotion of adult grizzly bears (Ursus arctos horribilis Linnaeus 1758), including stride parameters, gaits and analysis of three-dimensional ground reaction forces, with that of previously studied quadrupeds. At slow to moderate speeds, grizzly bears use walks, running walks and canters. Vertical ground reaction forces demonstrated the typical M-shaped curve for walks; however, this was significantly more pronounced in the hindlimb. The rate of force development was also significantly higher for the hindlimbs than for the forelimbs at all speeds. Mediolateral forces were significantly higher than would be expected for a large erect mammal, almost to the extent of a sprawling crocodilian. There may be morphological or energetic explanations for the use of the running walk rather than the trot. The high medial forces (produced from a lateral push by the animal) could be caused by frontal plane movement of the carpus and elbow by bears. Overall, while grizzly bears share some similarities with large cursorial species, their locomotor kinetics have unique characteristics. Additional studies are needed to determine whether these characters are a feature of all bears or plantigrade species.
jeb.biologists.org/content/218/19/3102.long
www.youtube.com/watch?v=or5z7yuOgEQ
www.youtube.com/watch?v=mzKDLDkHvEA
VGRF = vertical ground reaction force.
*Brown bears share some similarities with large cursorial species, their locomotor kinetics have unique characteristics.
*Vertical ground reaction forces is significantly more pronounced in the hindlimb,however,VGRF in forelim is still relatively high.
"The high medial forces (produced from a lateral push by the animal) could be caused by frontal plane movement of the carpus and elbow by bears"
It forced me to focused on the carpus of brown bears.
Sylvie McKenzie said she was driving along a highway a few kilometres west of Jasper when she noticed two bears running along the road ahead.She said she slowed down to let the bears cross the road, but only the female bear did so.
The second bear – a male – simply stopped and stared at her.
McKenzie said she then started driving, putting her car between the two bears.
Sylvie McKenzie
Asked whether she has any advice for drivers caught in the same situation in the future, McKenzie had simple advice: 'Stop, turn around, wait for a few minutes and go back.' (CBC)
"The male didn't like it at all, so he decided to take his feet, charge and hit my car with his two front paws," she said. "[He] just came and pounced on my car with full force and full speed."
McKenzie said the car rocked violently when the bear hit it, giving her a close-up view of the bear’s face.
"I could see his teeth, the drool on his face. I tried to speed up and put my foot on the gas pedal to get away as fast as I could."
Later, she found grizzly prints all over the side of her car, along with two big dents and several scratches.
It seem that carpal bone have a high resistance to mechanical deformation. Grizzly bear front paws are surprisingly heavy,maybe due to massive carpal bones?
This is the most accurate description of the striking ability IMHO:
"...The attack of a Bear is usually sudden and rapid, and he either tries to deal his opponent a blow with a forepaw by executing a rapid and violent movement to the side ,or he quickly trots up to his enemy ,suddenly lift himself on his hind-legs in the immediate proximity of his foe whom he tries to knock down with a violent stroke of the front-paw,or else he deals him a sound blow and gives him a quick bite..."
books.google.pl/books?id=SRsKAwAAQBAJ&pg=PA250&lpg=PA250&dq=Brehm%27s+with+a+forepaw+by+executing+a+rapid+and+violent+movement+to+forepaw+by&source=bl&ots=liizVWLpfp&sig=GMgP__qDrS8d9tPMep5NTrOsA9Q&hl=pl&sa=X&ved=0ahUKEwirlO2u2vfJAhXplHIKHaldD6MQ6AEIHjAA#v=onepage&q=Brehm's%20with%20a%20forepaw%20by%20executing%20a%20rapid%20and%20violent%20movement%20to%20forepaw%20by&f=false
TBC......
EAR ATTACKS
(Copyright © 2001 by Steven P. French, M.D.)
The following is the text for the 43rd chapter in the Fourth Edition of Wilderness
Medicine, edited by Paul S. Auerbach, published by Mosby in 2001
en.wikipedia.org/wiki/Paul_Auerbach
BEAR-INDUCED INJURIES
Bear-inflicted injuries range from minor, treated on an outpatient basis, to
complex, requiring hospitalization and surgery, typically resulting in significant cosmetic
and functional disability. In this regard, bear attacks are similar to most other animal
attacks, particularly those inflicted by large animals.
The character of such injuries is determined in part by the three main sources:
teeth, claws, and paws. The teeth of bears, especially the canines, are large and sturdy.
Although the teeth are not particularly sharp, the power of the jaw muscles allows the
teeth to penetrate deep into soft tissues and to fracture facial bones and bones of the hand
and forearm with ease. The trauma characteristically results from punctures, with
shearing, tearing, and crushing forces (Figure 43-20).
The claws are another important source of trauma. Although the claws on the
front pads can be as long as human fingers, they are not particularly sharp on grizzlies
and polar bears. The bear’s shoulders, however, provide the force and speed that allows
claws to cause significant soft tissue damage in a scraping maneuver that results in deep,
parallel gashes. Because black bear claws are sharper and more curved, the cuts tend to
have sharper, less ragged edges.
The bear paw is capable of delivering a powerful force, resulting in significant
blunt trauma, particularly to the head and neck, ribcage, and abdominal cavity, especially
solid organ rupture. Therefore victims of bear attacks should be evaluated for occult
blunt trauma.
ORIGINAL PAPER
Large carnivore attacks on hominins during the Pleistocene:a forensic approach with a Neanderthal example
Edgard Camarós
www.academia.edu/12436456/Large_carnivore_attacks_on_hominins_during_the_Pleistocene_A_forensic_approach_with_a_Neanderthal_example
"...The present observation of a total of 45 forensic cases iscommensurate with this known attack pattern of bears.Figure 2a shows that within the 38 case studies with bone modifications, the main bone damage is located in the head zone(skullandmandible)and upper limbs(clavicle,humerus,radius, ulna, metacarpals, and hand phalanges). Bears tend toattack the victims head, causing wounds and fractures in that zone, and humans react by protecting themselves with their arms, causing damage in that region. Long-bone diaphyseal linear, comminuted, and segmental fractures in the upper limb are not rare,and finger amputation is also common(Dharetal.2008). All these bony injuries are frequently associated with general soft-tissue wounds (Fig. 2b), as observed in other cases (Rasool et al. 2010). Therefore, bone modification after a bear attack would appear to occur in the body areas where other general non-bony wounds are inflicted by the animal..."
www.academia.edu/12436456/Large_carnivore_attacks_on_hominins_during_the_Pleistocene_A_forensic_approach_with_a_Neanderthal_example
Unfortunately, I don't have access to this paper,but ....
Grizzly bear (Ursus arctos horribilis) locomotion: gaits and ground reaction forces
Catherine L. Shine, Skylar Penberthy, Charles T. Robbins, O. Lynne Nelson, Craig P. McGowan
ABSTRACT
Locomotion of plantigrade generalists has been relatively little studied compared with more specialised postures even though plantigrady is ancestral among quadrupeds. Bears (Ursidae) are a representative family for plantigrade carnivorans, they have the majority of the morphological characteristics identified for plantigrade species, and they have the full range of generalist behaviours. This study compared the locomotion of adult grizzly bears (Ursus arctos horribilis Linnaeus 1758), including stride parameters, gaits and analysis of three-dimensional ground reaction forces, with that of previously studied quadrupeds. At slow to moderate speeds, grizzly bears use walks, running walks and canters. Vertical ground reaction forces demonstrated the typical M-shaped curve for walks; however, this was significantly more pronounced in the hindlimb. The rate of force development was also significantly higher for the hindlimbs than for the forelimbs at all speeds. Mediolateral forces were significantly higher than would be expected for a large erect mammal, almost to the extent of a sprawling crocodilian. There may be morphological or energetic explanations for the use of the running walk rather than the trot. The high medial forces (produced from a lateral push by the animal) could be caused by frontal plane movement of the carpus and elbow by bears. Overall, while grizzly bears share some similarities with large cursorial species, their locomotor kinetics have unique characteristics. Additional studies are needed to determine whether these characters are a feature of all bears or plantigrade species.
jeb.biologists.org/content/218/19/3102.long
www.youtube.com/watch?v=or5z7yuOgEQ
www.youtube.com/watch?v=mzKDLDkHvEA
VGRF = vertical ground reaction force.
*Brown bears share some similarities with large cursorial species, their locomotor kinetics have unique characteristics.
*Vertical ground reaction forces is significantly more pronounced in the hindlimb,however,VGRF in forelim is still relatively high.
"The high medial forces (produced from a lateral push by the animal) could be caused by frontal plane movement of the carpus and elbow by bears"
It forced me to focused on the carpus of brown bears.
Sylvie McKenzie said she was driving along a highway a few kilometres west of Jasper when she noticed two bears running along the road ahead.She said she slowed down to let the bears cross the road, but only the female bear did so.
The second bear – a male – simply stopped and stared at her.
McKenzie said she then started driving, putting her car between the two bears.
Sylvie McKenzie
Asked whether she has any advice for drivers caught in the same situation in the future, McKenzie had simple advice: 'Stop, turn around, wait for a few minutes and go back.' (CBC)
"The male didn't like it at all, so he decided to take his feet, charge and hit my car with his two front paws," she said. "[He] just came and pounced on my car with full force and full speed."
McKenzie said the car rocked violently when the bear hit it, giving her a close-up view of the bear’s face.
"I could see his teeth, the drool on his face. I tried to speed up and put my foot on the gas pedal to get away as fast as I could."
Later, she found grizzly prints all over the side of her car, along with two big dents and several scratches.
It seem that carpal bone have a high resistance to mechanical deformation. Grizzly bear front paws are surprisingly heavy,maybe due to massive carpal bones?
This is the most accurate description of the striking ability IMHO:
"...The attack of a Bear is usually sudden and rapid, and he either tries to deal his opponent a blow with a forepaw by executing a rapid and violent movement to the side ,or he quickly trots up to his enemy ,suddenly lift himself on his hind-legs in the immediate proximity of his foe whom he tries to knock down with a violent stroke of the front-paw,or else he deals him a sound blow and gives him a quick bite..."
books.google.pl/books?id=SRsKAwAAQBAJ&pg=PA250&lpg=PA250&dq=Brehm%27s+with+a+forepaw+by+executing+a+rapid+and+violent+movement+to+forepaw+by&source=bl&ots=liizVWLpfp&sig=GMgP__qDrS8d9tPMep5NTrOsA9Q&hl=pl&sa=X&ved=0ahUKEwirlO2u2vfJAhXplHIKHaldD6MQ6AEIHjAA#v=onepage&q=Brehm's%20with%20a%20forepaw%20by%20executing%20a%20rapid%20and%20violent%20movement%20to%20forepaw%20by&f=false
TBC......