Femoral head ostectomy (FHO)
A salvage procedure that restores comfortable movement when the hip joint is irreversibly damaged, in cats and in small and medium-sized dogs: removal of the head and neck of the femur, after which a pain-free “false joint” forms.
What it involves
FHO (femoral head and neck excision) consists of removing the ball-shaped head of the femur, that is, the part of the hip that rubs against the socket and hurts. After the procedure we do not implant anything in its place — over time a fibrous scar forms where the joint was, a so-called false joint, and the limb is held in place by the muscles. The animal moves without pain, although the range of movement in the hip is slightly reduced.
The procedure works best in cats and in dogs up to about 20 kg, whose body weight does not overload the false joint. In large dogs a hip replacement is sometimes the better solution — if it is indicated, we refer you to a centre that performs it and discuss both options with the owner.
FHO is not an operation “to start with” — it is a solution for a joint that can no longer be repaired or when conservative treatment has stopped working.
When it is used
FHO is indicated for hip pain that is not controlled by medication and modification of activity: advanced dysplasia with degeneration, necrosis of the femoral head in young dogs of small breeds, recurrent or long-standing hip luxation, and fractures of the femoral head and neck that cannot be repaired.
We plan the procedure after an orthopaedic examination and X-rays. It is not urgent, but prolonged pain leads to muscle wasting, which lengthens recovery.
Indications: symptoms that should prompt a visit
- A cat has stopped putting weight on a hind leg after a fall or being hit by a car, and the X-ray shows a dislocation or fracture of the hip.
- A small dog (Yorkshire Terrier, Shih Tzu, Poodle) a few months old has started limping on a hind leg and the thigh muscles have visibly wasted.
- A dog with diagnosed dysplasia is still lame despite medication and restricted exercise.
- The hip has dislocated again after being reduced.
- The animal will not let you touch the hip area and avoids sitting down.
- A hip replacement was suggested, but it is not possible or not available.
Conditions for which we use it in particular
Diagnostics beforehand
Diagnosis is based on an orthopaedic examination and digital X-rays of the pelvis under sedation, taken in two views. The images show how badly the joint is damaged and let us confirm that the problem is in the hip and not in the knee or spine.
Before the procedure we carry out a pre-anaesthetic assessment (STD-01) with a blood test. In patients who have had an injury we also check the chest and abdomen.
How it proceeds
The animal arrives fasted. After premedication, a regional block and induction of general anaesthesia, the anaesthetist monitors ECG, oxygen saturation, capnography, blood pressure and temperature (STD-02). We reach the joint through a lateral approach, remove the femoral head and neck, smooth the cut edge and check that nothing rubs against the acetabulum. The procedure takes roughly 45–75 minutes.
After closing the wound we take a follow-up X-ray. The patient wakes up in the in-patient hospital with continuous pain control (STD-04) and most often goes home the next day.
Aftercare
Unlike most orthopaedic operations, after FHO movement is recommended from the first days: short, frequent lead walks and gentle passive flexing and extending of the limb, following the instructions we will give you. The sooner the animal starts using the leg, the better the false joint will form. A collar is worn until the stitches are removed after 10–14 days; pain relief is given for 2–3 weeks.
Check-ups are at 2 weeks and at 6 weeks. Call us if the animal is still not putting any weight on the limb after 2 weeks, or if the wound starts to weep. Full function becomes established within 2–4 months. We do not provide physiotherapy on site, but we will point you to a centre if it is needed.
Frequently asked questions
Will a dog walk normally without the femoral head?
In cats and smaller dogs, usually yes. The gait is almost imperceptibly changed and, above all, free of pain. In large dogs the outcome is less predictable, so we discuss alternatives.
Can FHO be performed in a cat?
Yes. Cats are in fact very well suited to this procedure because of their low body weight, and they quickly return to jumping.
How long does recovery take?
The first signs of the animal putting weight on the limb appear within 1–2 weeks, and full function returns after 2–4 months. Early, regular use of the leg is key.
We manage every case individually. The scope, indications and course described above are indicative; we agree the exact diagnostic and treatment plan during the consultation. This content is for information only and does not replace a veterinary consultation.
Do you have questions about femoral head excision?
Call us or book a consultation. We will set out the diagnostic and treatment plan in writing, before you decide.