Bit & Bridle

Equine Capped Hock

Other Names

  • Hock Bursitis
  • Acquired Bursitis of the Hock
  • Calcaneal Bursitis

What is a Capped Hock in Horses?

A capped hock is the swelling of the bursa (a fluid-filled sac) over the point of the hock — the calcaneal tuber, which is the bony prominence at the back of the hock joint. The bursa normally exists to reduce friction between the skin and the bone during movement. When the area is subjected to repeated trauma, the bursa becomes inflamed and produces excess fluid, resulting in the characteristic soft, fluctuant swelling that gives the condition its name.

Capped hocks are among the most common bursitis conditions in horses and are largely a cosmetic issue in the majority of cases. Most horses with a capped hock are not lame, and the swelling — while noticeable — does not impair normal function. However, acute or severe cases can be associated with pain, and some horses develop fibrous, permanent thickening of the bursa wall if the cause of trauma is not removed. Understanding the cause is the key to management.

Causes

Capped hocks are almost always caused by repeated or acute trauma to the point of the hock:

  • Kicking the stable wall: The most common cause. Horses that habitually kick at the stable walls, doorframes, or partitions repeatedly traumatise the hock against a hard surface.
  • Trailer or lorry travel: Horses that scramble or have difficulty balancing in transport can bang their hocks against the partition or ramp repeatedly during transit.
  • Lying on hard or inadequate bedding: Insufficient bedding allows the horse’s hock to contact the floor directly when lying down, causing pressure trauma.
  • Falling or rolling: A single significant trauma from a fall can initiate acute bursitis.
  • Conformation: Horses with naturally close hocks or “cow-hocked” conformation may be more prone to self-trauma when moving.

Symptoms and Signs

  • Soft swelling: A round, fluctuant (fluid-filled) swelling directly over the point of the hock. In early or acute cases, it is soft and compressible.
  • Firm or hard swelling: In chronic cases, the bursal wall becomes thickened and fibrotic, giving a firmer consistency that may not reduce even if the initial fluid resolves.
  • Heat and discomfort: Acute cases may show local heat and some discomfort on palpation.
  • Lameness: Uncommon but can occur in acute or severely inflamed cases. Most horses with capped hocks are not lame.
  • Skin abrasion: In cases caused by repeated wall-kicking or trailer scrambling, skin damage and hair loss at the point of the hock may be present.

Diagnosis

Diagnosis is clinical and straightforward in most cases:

  • Physical examination: The location and character of the swelling are diagnostic. Palpation to determine whether it is fluid-filled or fibrotic, and to assess for pain or heat.
  • Ultrasonography: Useful to differentiate simple bursitis from more complex swellings involving the joint itself or the surrounding tendons. Can also identify bursal wall thickening.
  • Radiography: Generally not required for typical capped hocks, but may be indicated if there is suspicion of underlying bone involvement or fracture following trauma.
  • Aspiration: Drawing fluid from the bursa can confirm the diagnosis and rule out infection. Infected bursae (septic bursitis) require urgent treatment and have a different management approach.

Treatment

Treatment depends on whether the case is acute or chronic, and whether there is pain or lameness:

  • Remove the cause: This is the single most important step. Identify and eliminate the source of trauma — improve bedding depth, address stable-kicking behaviour, use hock boots during transport.
  • Cold therapy: In acute cases, cold-hosing or ice packs applied to the hock for 20 minutes several times daily can reduce inflammation and swelling.
  • NSAIDs: Anti-inflammatory medication (phenylbutazone or meloxicam) may be prescribed for painful acute cases.
  • Drainage and injection: In some cases, the bursa may be drained and an anti-inflammatory or corticosteroid injected under veterinary supervision. This can help reduce swelling but is of limited benefit if the traumatic cause is not removed, as the fluid typically re-accumulates.
  • Hock boots: Protective boots worn over the hock region can cushion the area from further trauma and are particularly useful during transport and in horses with kicking habits.
  • Surgical intervention: Rarely required for simple capped hocks, but fibrous, permanent bursal thickening that causes cosmetic or functional concern may be addressed surgically. This carries risks including infection and prolonged healing, and is generally only considered when conservative measures have failed and the deformity is significant.

Prevention

  • Maintain adequate, deep bedding — banks around the stable walls are helpful for horses that lie close to the edges.
  • Fit rubber matting in stables to cushion the floor and protect pressure points.
  • Use hock boots during transport, particularly for horses known to scramble.
  • Address stable-kicking behaviour — identify the trigger (boredom, anticipation of feeding, neighbour interactions) and manage it through environmental enrichment, changed management routines, or anti-weave grilles.
  • Check transport vehicles for sharp edges or protrusions at hock height.

Prognosis

The prognosis for capped hocks is generally good in terms of soundness. Most horses remain fully functional and are not lame. The main concern is cosmetic — the swelling may persist indefinitely, particularly if the cause was not addressed early or if fibrous thickening has occurred. Chronic, fibrotic capped hocks rarely resolve fully and should be regarded as a permanent blemish. In show horses or disciplines where conformation and appearance are judged, this may be relevant to consider. Functionally, the horse’s performance is rarely affected.

When to Call the Vet

Most capped hocks can be managed without urgent veterinary attention, but contact your vet if:

  • The swelling is accompanied by significant lameness
  • The area is very hot, painful, or the skin is broken
  • The swelling increases rapidly or is unusually firm
  • You are unsure whether the swelling involves the hock joint itself rather than the bursa
  • The horse sustained a direct blow to the hock and you are concerned about a fracture

Frequently Asked Questions

Will a capped hock affect my horse’s performance?

In the vast majority of cases, no. Capped hocks are primarily a cosmetic blemish and do not impair the horse’s ability to work, compete, or perform. The bursa sits on the point of the hock and does not involve the hock joint itself. Unless there is pain or associated lameness — which is uncommon — horses with capped hocks can continue in normal work. If you notice your horse favouring the leg or working differently, have it assessed by a vet to rule out other concurrent issues.

Can a capped hock go away on its own?

Recent, acute swellings — where the fluid has only just accumulated — have a reasonable chance of resolving with rest and removal of the cause. However, the longer the swelling has been present, the less likely it is to disappear completely, as the bursal wall thickens and becomes fibrotic over time. Early intervention — including removing the cause and cold therapy — gives the best chance of resolution.

Is a capped hock the same as a capped elbow?

The mechanism is the same — bursitis from repeated trauma — but the anatomical location is different. A capped elbow (also known as a shoe boil or olecranon bursitis) affects the point of the elbow, most commonly caused by the shoe or heel of the front foot contacting the elbow when the horse lies down. Both are managed similarly: remove the cause, and treat inflammation in the early stages. Capped elbows are often caused by heel calkins on shoes or a shoe that is too wide.

Should I use a bandage or support wrap on a capped hock?

Pressure bandaging over the point of the hock is difficult to achieve safely and risks causing complications if incorrectly applied. It is not generally recommended as a first-line approach. Hock boots designed to apply gentle, even pressure over the point of the hock are a safer option if compression is desired. Your vet will advise on the best approach for your horse’s specific situation.