O R T H O P E D I C SPro cedu re s P ro
Femoral Head & Neck Ostectomy
Femoral head and neck ostectomy (FHO) is a commonlyperformed procedure for surgical treatment of traumaticand chronic conditions affecting the hip.
The option to do an FHO is typically presented along with
other surgical alternatives. Some surgeons see it as a last resort
or a “salvage” procedure, whereas others believe it to be a pri-
mary recommendation for many orthopedic diseases of the hip.
INDICATIONS
Common indications for an FHO include:
� Femoral head and neck fractures
� Catastrophic acetabular fractures
� Coxofemoral hip luxations
� Failed total hip replacements
� Chronic pain associated with hip degenerative joint disease
(including traumatically induced disease, Legg-Perthes dis-
ease, and canine hip dysplasia).
Excision of the femoral head and neck palliates pain by elimi-
nating bony contact between the pelvis and femur, allowing for-
mation of a pseudoarthosis. The pseudoarthrosis that forms
comprises dense fibrous tissue lined by a synovial membrane.
OUTCOME
The procedure has the best outcome and is typically recom-
mended for mature pets and dogs weighing < 17 kg; however,
physically fit dogs of all sizes tend to rehabilitate and respond
favorably regardless of their weight. In addition, muscle mass
has been found to be one of the most important variables in
determining outcomes of the procedure.
Postsurgical FHO patients have some degree of limb shortening
and gait abnormality; however, with aggressive rehabilitation,
these animals have been reported to respond well to the proce-
dure and return to an active lifestyle.
Procedures Pro / NAVC Clinician’s Brief / February 2011......................................................................................................................................................................55
Laura E. Peycke, DVM, MS, Diplomate ACVS
Texas A&M University
Peer Reviewed
CONT INUES
AUTHOR INSIGHT
A thorough review and
understanding of the
craniolateral approach
to the hip is recom-
mended. Preservation
and reconstruction of
the supportive soft tis-
sues are keys to a quick
return to ambulation
and long-term function.
Recognition of the ori-
gin and insertions of the
hip musculature is espe-
cially important if the
FHO is performed on a
hip that is luxated or
traumatized.
FHO = femoral head and neck ostectomy
Pro cedu re s P ro CONT INUED
56......................................................................................................................................................................NAVC Clinician’s Brief / February 2011 / Procedures Pro
STEP BY STEP FEMORAL HEAD & NECK OSTECTOMY
The animal should be routinely anesthetized using a premedication, an induc-
tion agent, and gas anesthesia; then placed in lateral recumbency with the
affected limb hung and aseptically prepared for surgery (A).
The hip is then draped routinely to
allow manipulation of the limb. A
proper craniolateral approach to the
hip is dependent on the identification
of the ischial tuberosity (white arrow),
the greater trochanter (arrowhead),
and iliac wing of the pelvis (red arrow)
(B).
STEP 1
A B
The skin incision should be made slightly cra-
nial to the greater trochanter in a proximal to
distal direction. The biceps femoris, tensor fas-
cia lata, and gluteal musculature should be iden-
tified and minimally disrupted until the
muscular planes are appreciated. The plane
between the tensor fascia lata and biceps
femoris are incised and separated. The tensor
fascia can then be retracted cranially, whereas
the biceps musculature is retracted caudally. The
superficial and middle gluteal muscles (arrow)
are identified and retracted dorsally without
excision of the musculature or tendinous inser-
tions. The deep gluteal muscle is identified by
the arrowhead.
STEP 2
Landmarks for the femoral head and neck are now visible
and include the medial aspect of the base of the greater
trochanter (arrow) and lesser trochanter (arrowhead),
located on the medial cortex of the femur. With adequate
elevation of the origin of the vastus lateralis muscle, direct
palpation of the lesser trochanter is possible and should
be performed. The lesser trochanter is best appreciated
as a small “bump.”
The insertion of the iliopsoas muscle is also palpable at or
slightly distal to the lesser trochanter. Ideally, this muscular
insertion is preserved during the excision of the femoral neck,
but not at the expense of eliminating bony contact of the medial
femoral cortex with the pelvis.
Figure A shows the femoral head and neck prior to ostectomy;
Figure B shows how the femur should look when the correct
cut is made during ostectomy.
Procedures Pro / NAVC Clinician’s Brief / February 2011......................................................................................................................................................................57
At this point, identification of the tendon of the deep gluteal
muscle (arrow) is possible (A). Gentle elevation (with a
periosteal elevator) of this tendon allows partial tenotomy and
identification of underlying hip joint capsule. The joint capsule
can then be identified and incised in a radial fashion along the
acetabulum and onto the femoral neck. Continuation of the
incision along the origin of the vastus lateralis is recommended.
Elevation of the vastus lateralis musculature can be performed
and should be extended until full exposure of the femoral neck
is accomplished (B).
STEP 3
Because the
hip has been
draped “out,” movement of the hip and
easier identification of the hip joint are
possible. Effective use of assistants and
additional Gelpi and Hohmann retrac-
tors are important for visualization and
adequate exposure of the femoral head
and neck. When using pointed retrac-
tors, care must be taken to avoid trauma
to the sciatic nerve, which is located cau-
dally in relation to the hip joint.
The head of the femur is freed
from the remaining joint cap-
sule and round ligament with
curved Mayo scissors or a Hatt
spoon. Complete excision of the
round ligament is important to
allow disarticulation of the hip
and protection of deep struc-
tures when excising the femoral
head and neck.
STEP 4AUTHOR INSIGHT
CONT INUES
To position the saw or
osteotome and perform ade-
quate excision of the femoral
neck, the limb must be main-
tained in external rotation so
that the knee is positioned at
90 degrees to the table while
the cut is being made. An
assistant can help the surgeon
maintain the limb in the
proper position.
AUTHOR INSIGHT
STEP 5
A
B
A
B
STEP 8 Once the cut is completed, the tissue to be removed is grasped with a
bone-holding forcep. The femur is then carefully palpated for residual
bony prominences or irregularities. The hip is placed through a thor-
ough range of motion. Any “grinding” or bony contact between the
femur and hip should not be ignored.
At this point, the use of
rongeurs or a rasp can be used
to excise remaining tissue and
to smooth rough surfaces (A).
Inspection of the resected
femoral head and neck can give
some insight as to whether
additional tissue needs to be
excised (B).
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58......................................................................................................................................................................NAVC Clinician’s Brief / February 2011 / Procedures Pro
STEP 6
Once the parameter for the femoral neck is appreci-
ated, a line may be marked for accurate positioning
of an osteotome (at least 2- to 3-cm wide) or power
saw. The cutting device should be positioned on this
line and then tilted toward the patient’s head so that
the ostectomy is being directed in a caudal and
medial direction. This ensures adequate bony tissue
will be removed on the most caudal and medial
aspect of the femur.
The tendency to position the osteotome or saw in a
perpendicular position in relation to the femoral
neck will lead to incomplete excision of the femoral
neck and could result in residual contact between
the femur and pelvis. The orientation of the cutting
instrument should be tilted a few degrees toward
the dog's head.
STEP 7
Prior to the ostectomy,
Hohmann retractors
can be placed on both
the cranial and caudal
aspects of the femoral
neck. These retractors
will help with tissue
retraction and protect
the sciatic nerve and
underlying soft tissues.
With external rotation
of the limb being
maintained, the cut is
made.
A
When palpating the hip joint, free
movement should exist through a
complete range of motion. Careful
debridement with rongeurs on the
medial cortex can assist with elim-
ination of bony contact.
AUTHOR INSIGHT
B
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STEP 9
Once smooth range of motion has been acquired, closure of the hip may be
performed. Interpositioning of soft tissue between the femur and acetabulum
may be performed at this stage but remains controversial; proponents believe
this additional step increases the soft tissue “padding” between the ostectomy
site and pelvis. A positive outcome has been noted in short-term reports; how-
ever, there is no reported difference in long-term outcome.
In my experience, this technique not only requires additional soft tissue dissec-
tion and is unnecessary for long-term positive results but may also increase the
chances of deep tissue necrosis and infection.
STEP 10
Prior to closure, the surgical area
should be flushed with sterile saline.
Closure can be performed by closing
any residual joint capsule over the
acetabulum using 0 or 2-0 absorbable
suture. One or 2 mattress sutures can
then be placed in the deep gluteal
tendon to repair the previous teno-
tomy site. The vastus lateralis can
then be reattached to the deep tissues
by using simple interrupted sutures.
All other superficial tissues are closed
routinely.
Orthogonal
view post -
operative radiographs should always
be taken to ensure adequate excision
of the femoral head and neck.
AUTHOR INSIGHT
FHO = femoral head ostectomy
POSTOPERATIVE CARE
The postoperative period is extremely
important to the recovery and return to
function. It is critical to the success of
the procedure to be clear about the reha-
bilitation plan with the client.
� Rehabilitation in the form of passive
range of motion and controlled activ-
ity is encouraged and should be
explored within the first days after
surgery.
� Swimming is also acceptable during
rehabilitation but should be postponed
until after the incision has healed.
� Ice and heat therapies, along with
antiinflammatory medications, can be
used to assist with pain management.
� Frequent rechecks to ensure mainte-
nance of hip range of motion should
be performed.
COMPLICATIONS
Complications associated with FHOs
include decreased range of motion (espe-
cially abduction and extension of the
hip), limb shortening, muscle atrophy,
infection, and loss of function. A recent
study reported that there may be discrep-
ancies between the results of objective
clinical data and subjective observations
by owners, but a high degree of owner
satisfaction was reported following FHO.
PROGNOSIS
If an FHO is performed properly (ade-
quate ostectomy and careful soft tissue
manipulation) and followed by aggressive
rehabilitation, a positive outcome can be
expected; however, bony regrowth is
sometimes seen in dogs younger than 9
months of age.
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