PFFD

Question 1

Proximal Femoral Focal Deficiency

Answer 1

Congenital defect of the proximal femur

Question 2

spectrum of disease includes

Answer 2

• absent hip
• femoral neck pseudoarthrosis
• absent femur
• shortened femur

Question 3

Pathophysiology

Answer 3

defect in the primary ossification center (cartilage anlage)

Question 4

Genetics

Answer 4

• primarily sporadic etiology, but rare autosomal dominant form exists
• associated with sonic hedge-hog gene (limb bud)

Question 5

orthopaedic manifestations

Answer 5

• fibular hemimelia (50%)
• ACL deficiency
• coxa vara
• knee contractures

Question 6

Classification

Answer 6

Aitken classification

• Class*
• Femoral Head*
• Acetabulum*

A

present

normal

B

present

mildly dysplastic

C

absent

severely dysplastic

D

absent

absent

Question 7

Physical exam

Answer 7

• severe shortening of one or both legs
  
  • percentage of shortening remains constant with growth
• short bulky thigh that is flexed, abducted, and externally rotated
• normal feet (most common)

Question 8

Treatment

Answer 8

• Goals of treatment
• Nonoperative
• Operative

Question 9

Goals of treatment

Answer 9

treatment must be individualized based on

• ultimate leg length discrepancy
• presence of foot deformities
• adequacy of musculature
• proximal joint stability

Question 10

Nonoperative treatment

Answer 10

• observation
  
  • indications
    
    • often in children with bilateral deficiency
• extension prosthesis
  
  • indications
    
    • less attractive option due to large proximal segment of prosthesis
    • assists patient when attempting to pull self up to stand

Question 11

type of extension prosthesis

Question 12

classify Operative treatment

Answer 12

1. ambulation without prosthesis
   * limb lengthening with or without contralateral epiphysiodesis

​ 2. ambulation with a prosthesis

• knee arthrodesis with foot ablation
• femoral-pelvic fusion (Brown’s procedure)
• Van Ness rotationplasty
• amputation

Question 13

Discuss the operative treatment

Answer 13

ambulation without prosthesis

• limb lengthening with or without contralateral epiphysiodesis
  
  • indications
    
    • predicated limb length discrepancy of <20 cm at maturity
    • stable hip and functional foot
    • femoral length >50% of opposite side
    • femoral head present (Aitken classifications A & B)
  • contraindications
    
    • unaddressed coxa vara, proximal femoral neck pseudoarthrosis, or acetabular dysplasia

ambulation with a prosthesis

• knee arthrodesis with foot ablation
  
  • indications:
    
    • ipsilateral foot is proximal to the level of contralateral knee
    • prosthetic knee will not be below the level of the contralateral knee at maturity
    • need for improved prosthetic fit, function, and appearance
• femoral-pelvic fusion (Brown’s procedure)
  
  • indications
    
    • femoral head absent (Aiken classifications C & D)
• Van Ness rotationplasty
  
  • indications
    
    • ipsilateral foot at level of contralateral knee
    • ankle with >60% of motion
    • absent femoral head (Aiken classifications C & D)
  • surgical technique
    
    • 180 degree rotational turn through the femur
    • ankle dorsiflexion becomes knee flexion
    • allows the use of a below-knee prosthesis to improve gait and efficiency
• amputation
  
  • indications
    
    • femoral length <50% of opposite side
  • surgical technique
  • preserve as much length as possible
  • amputate through the joint, if possible, in order to avoid overgrowth which can lead to difficult prosthesis fittingfit for prosthesis for lower extremity after 1 year