Abstract
Introduction: Current classification schemes of fibular hemimelia concentrating on the radiographic appearance of the fibula do not adequately aid management of these patients. We reviewed our fibular hemimelia patient experience to devise a classification scheme which could serve as a better guideline for management decisions for this disorder.
Method: We reviewed the records/radiographs of all patients with the diagnosis of fibular hemimelia treated at our institution between 1957 & 1996. We excluded patients with PFFD, inadequate radiographs, or whose treatment was initiated elsewhere. We proposed a clinical management-oriented classification based on the presence/absence of a functional foot and overall limb shortening relative to the contralateral side (irrespective of the relative contributions of femoral & tibial shortening, or bilateral disease). The classification (with treatment guidelines) is:
Type I. Functional foot
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Shortening 5% or less (none or epiphysiodesis)
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Shortening 6–10% (epiphysiodesis or lengthening)
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Shortening 11–30% (1–2 lengthenings)
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Shortening > 30% (multiple lengthening or amputation)
Type II. Non-functional foot
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Upper extremities functional (amputation)
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Foot needed for prehension (no treatment)
A functional foot was defined as one which was or could be made plantigrade and stable with at least three rays.
Results: We identified 146 extremities in 122 patients with fibular hemimelia. 117 extremities were Type I (53 IA, 32 IB, 29 IC, and 1 ID), and 29 were Type II (28 IIA and 1 IIB). Limb length inequality remained proportional throughout growth, so that the distribution between groups did not change during growth.
Twenty-four patients had bilateral involvement. Twenty of 48 feet in these patients were Type II (nonfunctional). Nine patients with bilateral involvement had bilateral functional feet; these patients were short-statured, but were Type IA functionally.
The number of rays correlated directly with function: 100% of 5-rayed, 90% of 4-rayed, and 64% of 3-rayed feet were salvaged in this series. No feet less than 3-rayed were salvaged in this group; all such feet were associated with a completely absent fibula. Thirty-six of 63 limbs with completely absent fibula were classified as Type I. Eighty-two extremities in 65 patients have completed definitive management by virtue of skeletal maturity or amputation. A total of 39 extremities underwent Syme amputation, including 1 of 30 type IA, 1 of 11 type IB, 9 of 12 type IC, the single patient type ID, and all 27 type IIA deformities.
Conclusions: This classification system correlated well with the treatment required in our patients. While the amount of fibula present correlated with limb length inequality, 56% of patients in this series with absent fibula have been managed with limb salvage. The definition of a functional foot, and the boundary between multi-staged lengthening and amputation will remain an individual decision, but our classification scheme accurately predicted the amount of deformity present and the treatment required.
The abstracts were prepared by Professor Jegan Krishnan. Correspondence should be addressed to him at the Flinders Medical Centre, Bedford Park 5047, Australia.
