Longitudinal overgrowth of the femur stimulated by short-leg ambulation in unilateral partial tibia hemimelia Okechukwu Onwuasoigwe In the treatment of unilateral partial tibia hemimelia, complications from extensive lengthening to correct the marked shortening and recurrent failures of foot reconstructions do not allow limb salvage. Treatment by amputation with prosthetic replacement predominates. Very often, however, amputation is rejected by patients. A case we treated in infancy by complete reconstruction without lengthening walked full weight bearing on the short leg. Twelve years later, the ipsilateral femur manifested 6 cm overgrowth to reduce the shortening. Stimulation of accelerated growth in the partial tibia hemimelia limb by axial-directed stress of short-leg ambulation is suggested by this report, and its implication for enduring limb salvage is discussed. J Pediatr Orthop B 22:357–362  c 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins. Journal of Pediatric Orthopaedics B 2013, 22:357–362 Keywords: limb salvage, longitudinal growth stimulation, partial tibia hemimelia, short-leg ambulation University of Nigeria Teaching Hospital, Enugu, Nigeria Correspondence to Okechukwu Onwuasoigwe, MBSS, FWACS, FICS, P.O. Box 3336, 400001 Enugu, Nigeria Tel: +234 8037086727; e-mail: okechukwu.onwuasoigwe@unn.edu.ng Introduction Tibia hemimelia, a synonym for congenital longitudinal deficiency of the tibia, is rare, with a reported incidence of one in a million livebirths [1]. It presents with leg deformity and it is predominantly unilateral [2]. Clini- cally, it is classified as either partial or complete depending on whether or not the tibia is partly or totally deficient [3]. In the partial type, the distal femoral and proximal tibial epiphyseal cartilages are invariably present in infancy and a relatively normal knee is preserved [4]. However, the tibia deficiency varies from mere distal-end hypoplasia to the presence of only a short proximal stump. In the Jones et al. [4], and Kalamchi and Dawe [5] classifications, types II and III are variants of partial tibia hemimelia. The severity of the limb deformity mirrors the extent of tibial deficiency. Irrespective of its severity, the regular features of the deformity include (a) a fixed supinated foot in varus deviation, (b) marked shortening of the leg, and (c) flexion contracture of the knee, particularly in complete cases [3–5]. Other reported anomalies such as reduced first ray [5], diplopodia [6], etc. are infrequent and have an insignificant impact on the functional outcomes of treatment. In the treatment of tibia hemimelia, limb salvage is a surgical challenge. The few records of successes [7,8] were short-term results. Most other attempts reported repeated operations and eventual amputation [5,9,10]. In the partial type, complications from extensive lengthen- ing to equalize the limb lengths and recurrent failures of foot preservation procedures do not allow limb salvage. Treatment by primary amputation of the deformed part with prosthetic rehabilitation is predominant [10–12]. However, there are increasing reports of treatment refusals when amputation is prescribed [2,7,10]. With this phenomenon, the search for enduring limb salvage treatment will remain. A case of unilateral partial tibia hemimelia treated in infancy by complete reconstruction without lengthening, walking full weight bearing with the short leg, is presented. We report a significant long- itudinal overgrowth of the ipsilateral femur 12 years later and discuss its implications with limb salvaging in the condition. Case presentation A 1-year-old male patient presented in 1998 with a deformed right leg. The child’s development was normal, but the leg deformity impeded initiation of walking. Physical examination indicated a healthy child with a 6 cm shortened right leg and a fixed supinated foot in varus deviation (Fig. 1a and b). With reverse Allis testing [13], the shortening was limited to the leg. The knee functions were normal and the patient had no associated anomaly. Anteroposterior and lateral radiographs of the leg (Fig. 2a and b) indicated normal tibiofemoral articulation, prox- imal location of the fibula head, aplasia of the distal tibia, and varus foot. These features supported the diagnosis of partial (Jones type II) tibia hemimelia [4,5]. Operative treatment After counseling, the parents rejected any form of amputation and chose limb reconstruction. Using tourni- quet and general anesthesia, the deformity was recon- structed in a one-stage operation. Two incisions were used: the extended posteromedial [14] to the hind foot and anterolateral longitudinal incisions on the distal half Case report 357 1060-152X  c 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins DOI: 10.1097/BPB.0b013e32835957e2 Copyright © Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited.