Proximal femur focal def

Proximal Focal
Femoral Deficiency
DR.PONNILAVAN

INTRODUCTION
• An uncommon but complex problem.
• Femur shorter than normal and there is apparent discontinuity
between the femoral neck and shaft.
• In many cases the defect in the proximal femur will ossify as the child
grows older

EMBYOLOGY
• A teratogen is the term given to the agent that causes a malformation
in an embryo or fetus.
• The teratogen for PFFD is unknown.PFFD is not genetic.
• Some have limb buds on the fetus develop at about 28-32 days into
pregnancy and at 33-36 days the footis visible.
• If something affects the growth of fetus around this critical limb
formation time[4-6 weeks] it can lead to PFFD

EMBYOLOGY
• Proposed that it is caused by anoxia [oxygen deficiency],ischemia
[temporary blood supply deficiency],chemicals, hypothermia
,radiation, bacterial toxins, viral infections, enzyme and hormonal
changes.
• Thalidomide a only definite cause during intrauterine-taken by
mother between the 4th and 6th week of gestation.

What is the problem in PPFD??
• Proxiaml femur partially is absent
• Entire limb overall shortened.
• Leading to :
Limb length discrepancies
Malrotation
Proximal joint instability
Inadequate of proximal musculature

frequency
• Very rare
• 1 case per 50000 population to 1 case per 200000 population

Etiology
• Sclerotome subtraction theory:
Injury to the neural crest cells that from the precursors to the peripheral
sensory nerves of L4 and L5 results in PFFD.
• Theory by boden et al:
Defect in proximal proliferation and maturation of chondrocytes in the proximal
growth plate.

Etiology
• Agents :anoxia ,ischemia ,irradiation ,bacterial and viral infections and
toxins,hormones,mechanical energy ,thermal injury.
• Thalidomide a only definite cause during intrauterine-taken by
mother between the 4th and 6th week of gestation.
• No evidence of genetic etiology
• Maternal diabetes:femoral hypoplasia

Clinical presentation
Easily recognized
The femur is shortened ,flexed ,abducted, and externally rotated.
Flexion contractures of hip and knee present.
Bulbous proximal thigh tapers to the knee.
Hip instability :pistoning may be present.
Knee is uniformly unstable in an anteroposterior plane secondary to
absent cruciate ligaments.
Generalized knee hypoplasia.

Clinical presentation
• A high incidence of fibular deficiency[70-80%] and valgus feet .
o50% with some limb anomalies.
• Cleft palate ,clubfoot, congenital heart defects ,spinal anomalies –
rarely occur.
• 15% cases bilateral.

CLASSIFICATION
1. Aitken classification
2. Himanishi classification
3. Gillespie classification
4. Fixsen and Lloyd-Robert classification
5. Amstutz classification

CLASSIFICATION:AITKEN CLASSIFICATION

Hamanishi Classification
• More comprehensive than the Aitken system.
• It comprises 6 primary groups and 10 subgroups of femoral
malformation, with a category for almost every deformity.
• The mildest form is a shortened femur with no radiographic defect
(grade Ia); the most severe is complete absence of the femur (grade
V) .

Gillespie
Classification
• In the clinically based, treatment-oriented
Gillespie classification, patients are placed in
one of three groups. In group A, the femur is
up to 50% shorter than the normal femur,
and the hips and knees can be made
functional. These cases have also been called
congenital short femur.

GROUP B
• Group B comprises those patients with more
severely shortened femora in which the foot
on the affected side reaches above the
midtibia on the normal side, often at the
level of the normal knee. With the hips flexed
the femur is noted to be at or less than half
the length of the contralateral femur. These
patients are usually treated with amputation
or rotationplasty and prosthetic management

GROUP C
• Patients in group C have a subtotal absence
of the femur. Arthrodesis of the knee is not
indicated in group C cases, and these patients
will require prosthetic management.

Fixsen and Lloyd-Robert classification
Type-1
• Proxiaml femur is bulbous –no continuity between the femoral
head,neck and greater trochanter.
• A pseudoarthrosis may form distal to greater trochanter.

Type-2
• Tuft or cap ossification at proximal end of femur that is separated
from a blunt upper femoral shaft by an area of lucency.
• Pseudoarthosis present usually,and heals the femoral neck with a
varus deformity.
• Hip is unstable.

Type-3
• Femur is blunt and pointed in shape ,there is no tuft at the proximal
end of the shaft .
• All have unstable Pseudoarthrosis .

Amstutz classification
• Efficacy of MRI in classifying PFFD –more higher.
• Overs estimate the degree of deficiency and therefore ,MRI –best
modality
• MRI based classification-Amstutz classifcation

Amstutz classification
• Amstutz further subdivided Aitken’s classification into five types.
• He divided class A in to types 1 and 2.
• Type 1 is reserved for the milder form with simple femoral shortening
and coxa vara.
• In type 2, a subtrochanteric pseudarthrosis is present.
• The remaining types correspond to those of Aitken’s classification.

Treatment options
1. Equinus prosthesis only
2. Ankle disarticulation and prosthetic fitting
3. Ankle disarticulation and knee arthrodesis
4. Ankle disarticulation and femoral pelvic arthrodesis
5. Rotationplasty and knee arthrodesis
6. Rotationplasty and femoral-pelvic arthrodesis

treatment
• If final predicted discrepancy at maturity is less than 20cm ,the child
may be a suitable candidate for limb lengthening procedure.

Amputation
• Amputation of foot combined with knee arthrodesis.
• Consider also fusing the femur to pelvis to improve hip stability.
• Either a modified syme’s amputation or a boyd amputation

Knee fusion
for prosthetic
conversion in
PFFD
• Into a single skeletal lever arm by arthrodesis of
the knee in extension and syme ankle
disarticulation.

Knee fusion for
prosthetic conversion
in PFFD
• Anterior S shaped incision –
expose anterior aspect of
distal femur and proximal
tibia .
• Incision is extended laterally
to expose the lateral aspect
of the upper femur.

Knee fusion for
in PFFD
• Capsule and synovium of
knee opened
• With an oscillating saw the
rticular cartilage of upper
end of tibia is excised,until
the ossific nucleus of
epiphysis
• The distal femoral epiphysis
is completely removed.

Knee fusion for
in PFFD
• An 8 mm k-nail or similar
nail inserted retrograde
• First it is inserted distally
into the tibia ,exiting from
the sole of the foot.

Knee fusion for
in PFFD
• Nail passed proximally into the
femur ,impacting the lower end
of femur and the upper epiphysis
of tibia in extension.
• Ensure – proper rotational
alignment and fused knee is not
in flexion
• Intramedullary nail should be in
center to avoid growth
retardation.
• One and one half spica cast is
applied for immobilization.

Knee fusion for prosthetic
conversion in PFFD
• Six weeks postoperatively ,when the intramedullary nail is
removed ,a syme amputation is performed.

Knee fusion
for
prosthetic
conversion in
PFFD

Girl with bilateral femoral deficiency. Prostheses to
increase her height are the only appropriate
treatment measure.

Rotationplasty
• First described in 1930 by Borggreve, who used the procedure to treat
a knee severely damaged by tuberculosis.
• In 1950, van Nes described his technique of treating congenital
femoral deficiencies by rotating the foot of the affected limb 180
degrees so that the toes pointed posteriorly and the motion of the
foot and ankle controlled the prosthetic knee

Rotationplasty:goal
• To convert the affected limb to a functional below – knee amputation
in which the rotated foot serves as a knee joint.

After rotationplasty, the gastrocsoleus muscle provides
primary motor control to the ankle, which, in essence, is now
the “knee” extensor. Sensory feedback from the ankle also
allows the patient better proprioceptive control of the
prosthetic knee

• In a study comparing the gait mechanics of patients who had
undergone van Nes procedures with those who had undergone Syme
amputations, the patients treated with rotationplasty demonstrated
better prosthetic limb function and fewer compensations with the
contralateral normal limb.

PFFD
• When the hip is stable and the femoral anatomy is relatively normal
,the two treatment options are knee arthrodesis with either a syme
amputation or a rotationplasty.
• When the hip is unstable ,the current treatment options are a steel
fusion to the pelvis with either a syme amputation or a rotationplasty
or brown ilio femoral fusion with rotationplasty.

Steel procedure: the femoral segment is fused to
the pelvis (iliofemoral fusion) in a flexed position,
and the knee functions as a hip joint

Limb Lengthening
• The goals of limb lengthening procedures are to correct the existing
deformity and to eliminate the length discrepancy.
• multiple complications, they should not be undertaken lightly.
• Current indications:congenital short femur include a limb that is
predicted to be at least 50% as long as the normal limb at maturity, a
predicted discrepancy of less than 17 to 20 cm, and a condition that
can be corrected in three or fewer separate limb length equalization
procedures.

Proximal femur focal def

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