Changes

*'''Action''':  Extends carpus and digit

*'''Action''':  Extends carpus and digit

The common digital extensor tendon passes over the dorsolateral aspect of the carpus, continuing distally over the dorsal metacarpus. The branches of the interosseous muscle (suspensory ligament) join the common digital extensor tendon before its insertion on the extensor process of the distal phalanx.  A minor branch inserts on the second phalanx and some fibres insert on the hoof cartilages. The common digital extensor tendon is surrounded by the extensor retinaculum and a protective synovial sheath. The tendon sheath begins approximately 10cm proximal to the carpus, extending distally to the level of the metacarpus.  

The common digital extensor tendon passes over the dorsolateral aspect of the carpus, continuing distally over the dorsal metacarpus. The branches of the interosseous muscle (suspensory ligament) join the common digital extensor tendon before its insertion on the extensor process of the [[Phalanges - Horse Anatomy#Distal Phalanx|distal phalanx]].  A minor branch inserts on the [[Phalanges - Horse Anatomy#Middle Phalanx|middle phalanx]] and some fibres insert on the hoof cartilages. The common digital extensor tendon is surrounded by the extensor retinaculum and a protective synovial sheath. The tendon sheath begins approximately 10cm proximal to the carpus, extending distally to the level of the metacarpus.  

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'''''Lateral Digital Extensor Tendon'''''

'''''Lateral Digital Extensor Tendon'''''

*'''Origin''':  Lateral digital extensor muscle on the lateral humeral epicondyle

*'''Origin''':  Lateral digital extensor muscle on the lateral humeral epicondyle

*'''Insertion''': Dorsolateral aspect of proximal phalanx

*'''Insertion''': Dorsolateral aspect of [[Phalanges - Horse Anatomy#Proximal Phalanx|proximal phalanx]]

*'''Action''': Extends the carpus and metacarpophalangeal joint

*'''Action''': Extends the carpus and metacarpophalangeal joint

The lateral digital extensor muscle arises from the lateral humeral epicondyle and forms the lateral digital extensor tendon on the lateral aspect of the antebrachium; caudal to the common digital extensor tendon. The tendon is enclosed within a synovial sheath as it extends distally over the metacarpus to insert on the dorsolateral aspect of the proximal phalanx.

The lateral digital extensor muscle arises from the lateral humeral epicondyle and forms the lateral digital extensor tendon on the lateral aspect of the antebrachium; caudal to the common digital extensor tendon. The tendon is enclosed within a synovial sheath as it extends distally over the metacarpus to insert on the dorsolateral aspect of the [[Phalanges - Horse Anatomy#Proximal Phalanx|proximal phalanx]].

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Arises approximately 10cm proximal to the carpus and extends to mid-metacarpal region.   

Arises approximately 10cm proximal to the carpus and extends to mid-metacarpal region.   

*'''Digital Sheath'''

*'''Digital Sheath'''

Arises at the distal metacarpus, approximately 5cm proximal to the metacarpophalangeal joint and extends to the middle of the second phalanx.  

Arises at the distal metacarpus, approximately 5cm proximal to the metacarpophalangeal joint and extends to the middle of the [[Phalanges - Horse Anatomy#Middle Phalanx|middle phalanx]].  

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'''''Superficial Digital Flexor Tendon (SDFT)'''''

'''''Superficial Digital Flexor Tendon (SDFT)'''''

*'''Origin''': Superficial digital flexor muscle on the medial humeral epicondlye

*'''Origin''': Superficial digital flexor muscle on the medial humeral epicondlye

*'''Insertion''': Middle phalanx

*'''Insertion''': [[Phalanges - Horse Anatomy#Middle Phalanx|Middle phalanx]]

*'''Action''': Flexes the proximal and middle phalangeal joints, stabilises metacarpophalangeal joint

*'''Action''': Flexes the proximal and middle phalangeal joints, stabilises metacarpophalangeal joint

Just proximal to the metacarpophalangeal joint, the SDFT forms a ring-like structure which wraps around the DDFT. This structure is known as the '''manica flexoria'''.  

Just proximal to the metacarpophalangeal joint, the SDFT forms a ring-like structure which wraps around the DDFT. This structure is known as the '''manica flexoria'''.  

From the distal metacarpus to the level of the middle phalanx, the SDFT and DDFT are enclosed by another synovial structure, the '''digital sheath'''.

From the distal metacarpus to the level of the [[Phalanges - Horse Anatomy#Middle Phalanx|middle phalanx]], the SDFT and DDFT are enclosed by another synovial structure, the '''digital sheath'''.

The SDFT divides into two branches at the distal end of the proximal phalanx. The branches insert on the lateral and medial eminences of the middle phalanx, a minority of fibres also insert on the lateral aspect of the proximal phalanx.  

The SDFT divides into two branches at the distal end of the [[Phalanges - Horse Anatomy#Proximal Phalanx|proximal phalanx]]. The branches insert on the lateral and medial eminences of the [[Phalanges - Horse Anatomy#Middle Phalanx|middle phalanx]], a minority of fibres also insert on the lateral aspect of the [[Phalanges - Horse Anatomy#Proximal Phalanx|proximal phalanx]].  

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'''''Deep Digital Flexor Tendon (DDFT)'''''

'''''Deep Digital Flexor Tendon (DDFT)'''''

*'''Origin''': Deep digital flexor muscle on the medial humeral epicondyle, radius and ulna

*'''Origin''': Deep digital flexor muscle on the medial humeral epicondyle, radius and ulna

*'''Insertion''': Distal phalanx

*'''Insertion''': [[Phalanges - Horse Anatomy#Distal Phalanx|Distal phalanx]].

*'''Action''': Flexes the distal phalanx

*'''Action''': Flexes the [[Phalanges - Horse Anatomy#Distal Phalanx|distal phalanx]].

The deep digital flexor tendon arises as three bellies from its origin on the medial humeral epicondyle, fusing to form a common tendon just proximal to the carpus on the caudal aspect of the limb.  The single tendon passes distally, enclosed in the '''carpal sheath''', through the '''carpal canal'''. In the mid-metacarpal region, the tendon is enforced by an accessory ligament ('''inferior check ligament'''). At the metacarpophalangeal (fetlock) joint, the DDFT passes though the '''manica flexoria''' and over the sesamoid groove. In the mid –region of the proximal phalanx, the DDFT runs between the branches of the SDFT and over the flexor cortex of the distal sesamoid ('''navicular''') bone to insert on the flexor cortex of the distal phalanx.  

The deep digital flexor tendon arises as three bellies from its origin on the medial humeral epicondyle, fusing to form a common tendon just proximal to the carpus on the caudal aspect of the limb.  The single tendon passes distally, enclosed in the '''carpal sheath''', through the '''carpal canal'''. In the mid-metacarpal region, the tendon is enforced by an accessory ligament ('''inferior check ligament'''). At the metacarpophalangeal (fetlock) joint, the DDFT passes though the '''manica flexoria''' and over the sesamoid groove. In the mid –region of the [[Phalanges - Horse Anatomy#Proximal Phalanx|proximal phalanx]], the DDFT runs between the branches of the SDFT and over the flexor cortex of the [[Phalanges - Horse Anatomy#Distal Sesamoid (Navicular) Bone|distal sesamoid]] ('''navicular''') bone to insert on the flexor cortex of the [[Phalanges - Horse Anatomy#Distal Phalanx|distal phalanx]].  

The '''navicular bursa''' is the space formed between the DDFT and the distal sesamoid ('''navicular''') bone, which is filled with synovial fluid. It extends beyond the borders of the distal sesamoid bone proximally, distally and laterally.  

The '''navicular bursa''' is the space formed between the DDFT and the [[Phalanges - Horse Anatomy#Distal Sesamoid (Navicular) Bone|distal sesamoid]] ('''navicular''') bone, which is filled with synovial fluid. It extends beyond the borders of the distal sesamoid bone proximally, distally and laterally.  

The distal parts of the superficial and deep digital flexor tendons are supported by three annular ligaments:  

The distal parts of the superficial and deep digital flexor tendons are supported by three annular ligaments:  

*Palmar annular ligament

*Palmar annular ligament