- 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 whether
the 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.
Loder RT, Herring JA: J Pediatr Orthop 1987;7:8.
Congenital aplasia and dysplasia of the tibia with intact fibula.
Classification
and management.
Jones D, Barnes J, Lloyd-Roberts GC: J Bone Joint Surg 1978;60B:31.
Tibial agenesis.
Wehbe M, Weinstein SL, Ponstei IV:
J Pediatr Orthop 1981;1:395-399.
