FHO Surgery

Recently I saw one of my favorite patients (and equally favorite owners) gain full use of his left rear leg after a major orthopedic surgery I performed.  So rewarding.  It was my first femoral head ostectomy (FHO) on a Miniature Doberman Pinscher.  This 1.5 year old dog whose sole purpose in life is to chase squirrels had been intermittently lame and in some pain for a period of time.  After taking radiographs and working up the case, the diagnosis was determined to be Legg-Calve Perthe's Disease which causes a spontaneous degeneration of the femoral head and neck leading to a collapse of the coxofemoral (hip) joint and osteoarthritis.  The exact cause of this disease is unknown.  Some theories point towards a specific infarction of the vessels serving the proximal femur or necrosis of the subchondral bone leading to collapse and deformation of the femoral head (i.e. blood supply cut-off).  Typical age of onset is fairly young, anywhere from 3-13 months.  The disease is usually unilateral.  Breed predilections include terriers, miniature breeds, and toy breeds.  The prognosis post-operatively is excellent with an 84-100% success rate making for a very rewarding and satisfying surgery to perform.  The main benefit of performing the surgery early includes preventing the fact that the joint will continue to degenerate and eventually lead to an acute and/or painful fracture.  An FHO (also known as a femoral head and neck excision) is an orthopedic surgery involving slicing off a part of the femur (your big thigh bone) near the hip joint and then suturing the joint back together.  The surgery was exciting and challenging.  I LOVE doing surgeries, and I especially LOVE trying new procedures.  Here is how the surgery "technically" went:
The patient was asceptically prepared for an epidural. An epidural was injected into the epidural space at the junction of the 7th lumbar vertebrae and the 1st sacral vertebrae.  Then the patient was placed into right lateral recumbency, clipped, and asceptically prepared from the dorsal midline to the middle of the tibia for a femoral head and neck ostectomy using the hanging limb technique. A craniolateral elliptical incision/approach was used beginning just cranial to the greater trochanter of the femur. Muscle fascial planes were bluntly dissected layer by layer. The tensor fascia late muscle was incised for exposure. The biceps femoris muscle was retracted caudally and the tensor fasciae latae muscle was retracted cranially. The vastus lateralis muscle was incised and reflected ventrally. The joint capsule was incised and palpated. The round ligament of the femur was incised by placing lateral traction on the greater trochanter and subluxating the femoral head. The ostectomy was performed by externally rotating the limb to where the joint line of the stifle was parallel to the operating table. The line of ostectomy was identified perpendicular to the operating table at the junction of the femoral neck and the femoral metaphysis. An osteotome and a mallet was used to complete the cut. The femoral neck was palpated for irregularities. The irregular and sharp edges were removed with bone rongeurs. The joint capsule and deep gluteal muscle were sutured over the acetabulum with multiple cruciate sutures using 3-0 PDS. The vastus lateralis muscle and the tensor fascia latae muscle bellies were sutured back together individually and then together using a cruciate pattern and 3-0 PDS. The subcutaneous layer was closed using 2-0 PDS in a simple continuous pattern. The skin was closed using 2-0 PDS in an intradermal subcuticular pattern. Tissue adhesive was applied on top of the skin and surgical staples were incorporated for additional closure support.  Intra-operative intravenous cefazolin was administered.  Post-operatively, ketoprofen and buprenorphine were administered each once, subcutaneously, and at different time intervals.  Post-operatively, the patient must bear weight on the leg as soon as able. Passive physical therapy needs to be performed twice daily for 5-10 minutes at a time incorporating flexion and extension exercises as soon as the patient can tolerate it. Additionally, the coxofemoral joint needs to be ice-packed for 3 days. Lameness may still occur in damp weather or after heavy exercise or following periods of inactivity.  Post-surgical progress checks are necessary at 2 week intervals to ensure owner compliance with exercise stipulations.  Breeding of the patient and affected individuals should be discouraged.  So, to recap, although removing part of a patient's bone seems archaic and possibly backpedaling, it prevented a worse, more-painful outcome in the future.  But during the interim...honestly, I was frustrated.  I wanted my favorite little patient to have a miraculously expeditious recovery and be back to terrorizing squirrels just as soon as I removed the staples.  Not a chance.  Patience is a virtue.  Working on it.  It wasn't until months later that I really felt that the surgery was successful.  But in the end, Fido doesn't really care if he has to run on 3 legs temporarily.  And he's entirely back now with the squirrels not being quite as ecstatic for his recovery as me.