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Joints and Ligaments - Horse Anatomy (view source)

Revision as of 17:41, 17 October 2012

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====[[Hindlimb - Anatomy & Physiology#Coxafemoral|Coxafemoral/Hip Joint]]====

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The horse has a limited range of hip movement compared to the dog. This is mainly restricted to flexion and extension and is a result of the conformation of its femoral head, intra-articular ligaments and a large muscle mass around the joint. The '''ligament of the femoral head''' extends from the acetabulum to the fovea on the femoral head. Unlike other species, the horse also has an extra ligament present in the joint; the '''accessory ligament'''. The accessory ligament arises from the tendon of insertion of the ''rectus abdominis'' muscle and to a lesser extent ''external abdominal oblique'' muscle as part of the ''prepubic tendon'' and inserts on the fovea. Both ligaments pass through '''acetabular notch'''.

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The horse has a limited range of hip movement compared to the dog. This is mainly restricted to flexion and extension and is a result of the conformation of its [[Bones and Cartilages - Horse Anatomy|femoral head]], intra-articular ligaments and a large muscle mass around the joint. The '''ligament of the femoral head''' extends from the acetabulum to the fovea on the [[Bones and Cartilages - Horse Anatomy|femoral head]]. Unlike other species, the horse also has an extra ligament present in the joint; the '''accessory ligament'''. The accessory ligament arises from the tendon of insertion of the ''rectus abdominis'' muscle and to a lesser extent ''external abdominal oblique'' muscle as part of the ''prepubic tendon'' and inserts on the fovea. Both ligaments pass through '''acetabular notch'''.

===[[Hindlimb - Anatomy & Physiology#Stifle Joint|Stifle Joint]]===

====Femorotibial Joint====

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The femorotibial joint is formed by the femur and tibia. It is divided by '''menisci''' into proximal and distal segments. These communicate through open centres of the menisci where the condyles of the femur and tibia are in contact. The synovial membrane of the joint capsule, which is complete only in the horse, further divides the joint into medial and lateral compartments. The menisci are fibrocartilaginous structures that act as shock absorbers, reducing concussion on the joint as well as incongruency of the articular surfaces. Menisci are attached at the outer margins to the fibrous joint capsule and anchored at their ends mainly on the tibia by the '''cranial and caudal ligaments''', but the lateral meniscus has an additional ligament attaching it to the distal femur. The '''cruciate ligaments''' in the centre of the joint are important for stifle stability.

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The femorotibial joint is formed by the [[Bones and Cartilages - Horse Anatomy|femur]] and [[Bones and Cartilages - Horse Anatomy|tibia]]. It is divided by '''menisci''' into proximal and distal segments. These communicate through open centres of the menisci where the condyles of the [[Bones and Cartilages - Horse Anatomy|femur]] and [[Bones and Cartilages - Horse Anatomy|tibia]] are in contact. The synovial membrane of the joint capsule, which is complete only in the horse, further divides the joint into medial and lateral compartments. The menisci are fibrocartilaginous structures that act as shock absorbers, reducing concussion on the joint as well as incongruency of the articular surfaces. Menisci are attached at the outer margins to the fibrous joint capsule and anchored at their ends mainly on the [[Bones and Cartilages - Horse Anatomy|tibia]] by the '''cranial and caudal ligaments''', but the lateral meniscus has an additional ligament attaching it to the distal [[Bones and Cartilages - Horse Anatomy|femur]]. The '''cruciate ligaments''' in the centre of the joint are important for stifle stability.

====Femoropatellar Joint====

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The femoropatellar joint is formed by the femur and patella. The patella is anchored to the femur by the medial and lateral '''femoropatellar ligaments''' and to the tibia by three patellar ligaments:

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The femoropatellar joint is formed by the [[Bones and Cartilages - Horse Anatomy|femur]] and patella. The patella is anchored to the femur by the medial and lateral '''femoropatellar ligaments''' and to the tibia by three patellar ligaments:

*'''Middle Patellar Ligament'''

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The medial patellar ligament connects the parapatellar fibrocartilage to the medial aspect of the tibial tuberosity. This ligament contains tendinous elements of the ''sartorius'' and ''gracilis'' muscles.

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Contraction of the quadriceps while in rest enables the patella to be hooked over the trochlea of the femur due to the binding loop formed by the patella, middle and medial patellar ligaments. The '''femeropatellar joint''' capsule sometimes communicates with the '''lateral femerotibial''' cavity and usually with the '''medial'''. No communication exists between the femorotibial joints.

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Contraction of the quadriceps while in rest enables the patella to be hooked over the trochlea of the [[Bones and Cartilages - Horse Anatomy|femur]] due to the binding loop formed by the patella, middle and medial patellar ligaments. The '''femeropatellar joint''' capsule sometimes communicates with the '''lateral femerotibial''' cavity and usually with the '''medial'''. No communication exists between the femorotibial joints.

===Tibiofibular Joint===

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In the horse, this joint only exists proximally because the distal end of the fibula is fused to the tibia to form the lateral malleolus.

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In the horse, this joint only exists proximally because the distal end of the [[Bones and Cartilages - Horse Anatomy|fibula]] is fused to the [[Bones and Cartilages - Horse Anatomy|tibia]] to form the lateral malleolus.

===Tarsal Joint (Hock)===

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====Tarsocrural Joint====

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In the horse, this joint is formed between the tibia and talus only, since the distal end of the fibula is incorporated in the lateral malleolus of the tibia. There is communication with the proximal intertarsal joint.

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In the horse, this joint is formed between the [[Bones and Cartilages - Horse Anatomy|tibia]] and [[Bones and Cartilages - Horse Anatomy|talus]] only, since the distal end of the [[Bones and Cartilages - Horse Anatomy|fibula]] is incorporated in the lateral malleolus of the [[Bones and Cartilages - Horse Anatomy|tibia]]. There is communication with the proximal intertarsal joint.

====Proximal Intertarsal Joint====

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Proximally, there is articulation between the talus and calcaneus. Distally there is articulation between the central and fourth tarsal bones.

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Proximally, there is articulation between the [[Bones and Cartilages - Horse Anatomy|talus]] and [[Bones and Cartilages - Horse Anatomy|calcaneus]]. Distally there is articulation between the central and fourth [[Bones and Cartilages - Horse Anatomy|tarsal bones]].

====Distal Intertarsal Joint====

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Articulation between the central tarsal bone and the numbered tarsal bones.

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Articulation between the central [[Bones and Cartilages - Horse Anatomy|tarsal bone]] and the numbered [[Bones and Cartilages - Horse Anatomy|tarsal bones]].

====Tarsometatarsal Joint====

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Articulation between the small, numbered tarsal bones and the metatarsals.

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Articulation between the small, numbered [[Bones and Cartilages - Horse Anatomy|tarsal bones]]and the [[Bones and Cartilages - Horse Anatomy|metatarsals]].

====Ligaments of the Tarsus====

*'''Collateral ligaments''':

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**''Long lateral collateral'': Arises from the lateral maleolus of the tibia and terminates on the proximal end of metatarsal IV (lateral splint). Between these points it attaches to the lateral tarsal bones.

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**''Long lateral collateral'': Arises from the lateral maleolus of the [[Bones and Cartilages - Horse Anatomy|tibia]] and terminates on the proximal end of [[Bones and Cartilages - Horse Anatomy|metatarsal IV]] (lateral splint). Between these points it attaches to the lateral [[Bones and Cartilages - Horse Anatomy|tarsal bones]].

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**''Short lateral collateral'': Deep to the long lateral collateral. It arises from the lateral maleolus of the tibia and attaches via two branches, one to the calcaneus and one to the talus.

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**''Short lateral collateral'': Deep to the long lateral collateral. It arises from the lateral maleolus of the [[Bones and Cartilages - Horse Anatomy|tibia]] and attaches via two branches, one to the [[Bones and Cartilages - Horse Anatomy|calcaneus]] and one to the [[Bones and Cartilages - Horse Anatomy|talus]].

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**''Long medial collateral'': Arises from the medial malleolus and terminates on the proximal end of metatarsal II (medial splint). Between these points it attaches to the medial tarsal bones.

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**''Long medial collateral'': Arises from the medial malleolus and terminates on the proximal end of [[Bones and Cartilages - Horse Anatomy|metatarsal II]] (medial splint). Between these points it attaches to the medial [[Bones and Cartilages - Horse Anatomy|tarsal bones]].

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**''Short lateral collateral'': Deep to the long medial collateral. It arises from the medial malleolus and attaches via two branches, one on the calcaneus and one on the talus.

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**''Short lateral collateral'': Deep to the long medial collateral. It arises from the medial malleolus and attaches via two branches, one on the [[Bones and Cartilages - Horse Anatomy|calcaneus]] and one on the [[Bones and Cartilages - Horse Anatomy|talus]].

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*'''Long plantar ligament''': Extends on the plantar aspect of the hock from the calcaneal tuberosity distally to the proximal end of the third and fourth metatarsal bones and also attaches to the central and fourth tarsal bones.

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*'''Long plantar ligament''': Extends on the plantar aspect of the hock from the calcaneal tuberosity distally to the proximal end of the third and fourth [[Bones and Cartilages - Horse Anatomy|metatarsal bones]] and also attaches to the central and fourth [[Bones and Cartilages - Horse Anatomy|tarsal bones]].

==References==

*Budras, K. Sack, W.O., Anatomy of the Horse, 6th Edition (2012), Schlutersche Verlagsgesellschaft mbH & Co. KG

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