- Discussion:
- distal end of femur is hypoplastic, tibia is absent, & proximal dislocation of fibular head;
- incidence is 1 in 1 million.
- has a familial inheritance;
- tibial hemimelia may be terminal or intercalary, complete or incomplete.
- 30% percent of cases are bilateral;
- Clinical Presentation:
- extremity is shortened, w/ foot in rigid supinated position;
- knee joint may be unstable and contracted in flexion (it is important to determine whetherthe knee joint and the quadriceps are
functional enough to use a BKA or Syme prosthesis);
- limb length inequality;
- Associated Anomalies:
- approx 75% of all pts have associated skeletal anomalies;
- DDH occurs in 20%;
- lobster hand is also common;
- knee has severe flexion contracture & instability;
- foot has fixed equinovarus deformity w/ absence of one or more medial rays;
- Treatment:
- centralization of fibula (unpredictable)
- patients w/ a functional knee joint and quadriceps mechanism may function best with a Syme or BKA amputation (see pediatric
amputations);
- consider synostosis of the tibia to the fibula to prevent overgrowth;
- patients w/ a significant knee joint contracture may require knee disarticulation
- Radiographs: Case Examples:
Congenital longitudinal deficiency of the tibia.
Failure of centralization of the fibula for congenital longitudinal deficiency of the tibia.
Fibular transfer for congenital absence of the tibia: A reassessment.
Congenital aplasia and dysplasia of the tibia with intact fibula. Classification and management.