01/19/2026
Most injuries don’t just happen.
Some do, yes. Of course, fluke accidents happen.
More often than not, injuries are the consequential result of repetitive strain and subtle biomechanical imbalances compounding over time.
Hoof balance plays a critical role in how forces are distributed through the limb, ultimately affecting the whole body.
No hoof, no horse right?
There’s so many complex dynamics of hoof mechanics, but for this post particularly I am going to focus on long toe length and underrun heels.
A long toe functions as a lever, delaying breakover and significantly increasing strain on the deep digital flexor tendon (DDFT).
Every additional 1 cm of toe length, the force placed on the deep digital flexor tendon (DDFT) increases by approximately 110 pounds.
This does not occur in isolation.
Increased strain on the DDFT puts additional stress over the navicular bone, suspensory apparatus, and surrounding soft tissue structures.
Underrun heels, demonstrated in the attached image in conjunction with excessive toe length, further complicates things.
Now, the hoof’s shock absorbing structures such as the digital cushion and collateral cartilages are also compromised.
Underrun heels reduces the hoof’s ability to dissipate concussive forces that can exceed 2.5x the horse’s body weight at speed (Beckstett, 2013). Over time, this overload may contribute to chronic pain and pathology in the navicular region, as well.
Radiographic evidence also supports a strong relationship between long toe–low heel and changes in the coffin bone’s orientation, indicating structural remodeling and altered biomechanics.
Clinically, horses with underrun heels often present with excess stress of the coffin joint, navicular region pain, dorsiflexion of the coffin joint, and degenerative changes consistent with navicular syndrome; ultimately leading to lameness, decreased performance, and reduced athletic longevity.
Delayed breakover from long toes alters the entire limb’s biomechanics.
When combined with underrun heels, improper loading patterns and compensatory postural changes develop. These imbalances can create chronic tension throughout the myofascial system, affecting not only the distal limb but also the back, neck, pectorals, and hind end.
Over time, this may manifest as reduced range of motion, muscle tightness, poor performance, and increased injury risk.
Then we see common side effects that shine through when pain can no longer be masked…
𝐒𝐞𝐭𝐭𝐢𝐧𝐠 𝐁𝐚𝐜𝐤
𝐂𝐢𝐧𝐜𝐡𝐢𝐧𝐞𝐬𝐬
𝐆𝐚𝐭𝐞 𝐢𝐬𝐬𝐮𝐞𝐬
𝐃𝐮𝐜𝐤𝐢𝐧𝐠
𝐒𝐭𝐫𝐮𝐠𝐠𝐥𝐢𝐧𝐠 𝐭𝐨 𝐬𝐭𝐫𝐢𝐝𝐞 𝐨𝐮𝐭 𝐢𝐧 𝐚 𝐫𝐮𝐧
Hoof imbalances are not a cosmetic issue.
The DDFT inserts on the underside of the coffin bone (P3), making it particularly vulnerable to these forces. Studies reporting that only about 25% of horses with DDFT injuries return to their previous level of performance within 18 months, depending on injury type and treatment approach (Cillán et al., 2013).
When breakover is delayed and the hoof’s shock-absorbing structures are compromised, excessive forces are transmitted through the DDFT, navicular apparatus, and entire kinetic chain. Over time, these cumulative stresses predispose the horse to chronic pain, soft-tissue injury, degenerative change, and reduced athletic longevity.
Injury prevention does not start at the site of pain. This happens from ground up.
#𝙐𝙣𝙡𝙤𝙘𝙠𝙂𝙧𝙚𝙖𝙩𝙣𝙚𝙨𝙨
