- Discussion:
- among most frequent limb anomalies is partial or total absence of fibula;
- it is most common long bone deficiency and is the most common skeletal deformity in the leg;
- most often is unilateral;
- paraxial fibular hemimelia is the most common manifestation (only the postaxial portion of the limb is affected)
- commonly seen as complete terminal deficiency (lateral rays of the foot are affected as well);
- hemimelia can also be intercalary in which case the foot remain unaffected;
- it is prudent to remember that although congenital absence of fibula is evident, this condition is actually a total limb involvement;
- males are affected twice as often as females in most series;
- Clinical Presentation:
- involved limb is usually shortened, and the foot is in equinovalgus position;
- classically the skin has dimpling seen over the tibia;
- clinically, primary problems related to fibular hemimelia are
limb length inequality and foot/ankle instability;
- Associated Anomalies:
-
coxa vara
-
proximal femoral focal deficiency
- associated femoral shortening adds to limb length discrepancy;
- at skeletal maturity, this averages about 5 in / 12 cm;
- ankle instability;
- equinovarus/valgus foot (+/- absent lateral rays)
- lateral column deficiency of the foot;
- ref:
Fibular hypoplasia with absent lateral rays of the foot.
-
tarsal coalition;
- ref:
Talocalcaneal coalition in patients who have fibular hemimelia or proximal femoral focal deficiency. A comparison of the radiographic and pathological findings.
- anterior tibial bowing (vs.
anterolateral bowing)
- abnormality of the distal tibial physis;
- deficiency in muscles on the peroneal side of the leg;
- Treatment:
- treatment varies from a simple shoe lift, or bracing, or Syme amputation;
-
Limb Lengthening:
- indicated only for less severe cases w/ a relatively normal foot and ankle;
- ref: Management of congential fibular deficiency by Ilizarov technique.
LS Miller and DF Bell.
JPO. Vol 12. 1992. p 651-657.
-
Syme Amputation:
- preferred method of treatment is early ablation of foot by ankle disarticulation of
Syme type, producing a sturdy end-bearing stump;
- amputation is usually done at about 10 months to two years of age;
- w/ extreme limb length inequality, or when gross instability at foot/ ankle is present, Syme amputation allows
application of a highly functional
below-knee prosthesis;
- conversion to a long amputation stump addresses the leg length problem and avoids multiple procedures
necessary to maintain plantigrade foot and limb of equal length;
- in the study by JJ. McCArthy et al, the authors compared functional results between amputation vs tibial lengthening;
- authors specifically compared activity restrictions, pain, satisfaction, complications, number of
procedures, and cost, in children with fibular hemimelia;
- 30 limbs in 25 patients treated with either an amputation or a lengthening procedure and followed
for at least two years were studied;
- 15 patients underwent amputation, and ten patients underwent lengthening of the tibia;
- mean age was 1.2 years at the time of amputation and 9.7 years at the time of initial lengthening;
- patients who underwent amputation were able to perform more activities than those who
had a lengthening (mean activity score, 0 compared with 1.2 points; p < 0.05), and they had
less pain (mean pain score, 0.2 compared with 1.2 points; p = 0.091), were more satisfied
and had a lower complication rate (0.37 compared with 1.91; p < 0.05).
- patients who underwent amputation also had fewer procedures (1.9 compared with 7.0; p < 0.05),
at a lower cost ($7016 compared with $26,900; p < 0.05), than those who had a lengthening.
- lengthening was successful in equalizing limb lengths; the mean limb-length discrepancy, assessed
in nine of eleven limbs, was 0.7 centimeter;
- ref:
Congenital longitudinal deficiency of the fibula: follow-up of treatment by Syme amputation.
Congenital absence of the fibula.
Treatment by Syme amputation: Indications and technique.
Wood WL, Zlotsky N, Westin GW: JBJS 1965;47A:1159.
Syme amputation: An evaluation of the physical and psychological function in young patients.
Herring JA, Barnhill B, Gaffney C: JBJS 1986;68A:573-578.
Amputation and prosthesis as definitive treatment in congenital absence of the fibula.
Kruger LM, Talbott RD: JBJS 1961;43A:625-642.
Congenital longitudinal deficiency of the fibula (fibular hemimelia). Parental refusal of amputation.
Fibular Hemimelia: Comparison of Outcome Measurements After Amputation and Lengthening. JJ. McCArthy.
J Bone Joint Surg [Am] 82-A: 1732-5, 2000
Vascular dysgenesis associated with skeletal dysplasia of the lower limb.
Treatment of hemimelias of the lower extremity. Long-term results.
Amputation or limb-lengthening for partial or total absence of the fibula.
The Gruca operation for congenital absence of the fibula.
Symptomatic ossicles of the lateral malleolus in children.
