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Background: Infantile Blount disease is a developmental condition characterized by disorganized endochondral ossification in the medial aspect of the proximal tibial physis., Objective: To describe the MR imaging abnormalities in the proximal tibia, distal femur, menisci and ligaments of children with infantile Blount disease., Materials and Methods: We retrospectively evaluated 11 children (18 total knee MR examinations) with infantile Blount disease and compared them with an age-matched control group with normal MR examinations. Morphological and morphometric measurements were performed., Results: The medial menisci were enlarged with increased T2 signal intensity in all MR examinations. The medial femoral epiphyseal cartilage showed abnormal foci of increased signal intensity in nine (50%). The mid-coronal thickness of the medial tibial epiphyseal cartilage was decreased with concomitant increase in the mid-coronal joint space distance. Angular measurements of the proximal tibia demonstrated posteromedial down-sloping configuration., Conclusions: Most severe abnormalities of infantile Blount disease occur in the medial compartment of the knee, especially at the medial tibial physis and epiphysis. However, other important structures of the knee and the lateral compartment are often affected. MR imaging helps to delineate the extent of multiple tibial and extra-tibial abnormalities, including meniscal abnormalities, perichondrial membrane changes and premature physeal closure.

Introduction: Progressive angular deformity after surgical transtibial amputation in the pediatric population has not been described in the literature. Angular deformity in amputation stumps may lead to problems with pain and fitting of the prosthesis. The aim of this study was to evaluate the incidence and pattern of angular deformity and its treatment., Methods: A retrospective review of 21 patients (24 limbs) with transtibial amputation was carried out. The mean age was 7.4 years (range: 1 to 18). There were 8 congenital and 13 acquired amputations (7 trauma, 4 infection, 1 tumor, 1 vascular). Sequential radiographs were evaluated for frontal and sagittal plane alignment. Deformity was defined as an angular deviation greater than 5 degrees., Results: Angular deformity was identified in 8 (38%) patients. Two patients had valgus deformity, 2 had varus deformity, and 1 had isolated recurvatum deformity. One patient had valgus procurvatum and 1 patient had varus recurvatum deformity. There was a mean stump revision rate of 1.38 in the congenital group and 0.85 in the acquired group. Three patients underwent deformity correction using an external fixator owing to difficulty with prosthetic fitting. All patients experienced improved fitting of their prosthesis after surgery., Conclusions: Angular deformity can arise in children with transtibial amputations and may influence prosthesis fit and gait. Clinical and radiographic surveillance is important, and surgical correction may be of benefit. Surprisingly, stump revision rate was similar in both groups.

Background: Many surgical procedures have been proposed for treatment of Blount disease (tibia vara). Gradual correction of Blount disease has been described with both unilateral and circular external fixators. The purpose of this study was to compare the clinical and radiographic results of gradual correction for severe or recurrent Blount disease using the Biomet Multi-Axial Correction (MAC; Biomet Trauma, Parsippany, NJ) external fixator to our historical controls using other devices (such as the Ilizarov and Garche T-clamp)., Methods: A total of 58 corrections were performed on the 54 limbs in 38 patients. Charts were analyzed to evaluate the presence of complications during the course of external fixator treatment. The tibiofemoral, anatomic medial proximal tibial, and proximal posterior tibial angles were measured on radiographs taken before application of the external fixator and after removal to compare the correction achieved by the MAC fixator and the other fixators., Results: The mean values for the tibiofemoral angle, anatomic medial proximal tibial angle, and proximal posterior tibial angle were similar between the 2 groups after treatment and at follow up. The rate of complications between the 2 groups was also not significantly different., Conclusions: The MAC external fixator provides an acceptable alternative for gradual correction of Blount disease., Level of Evidence: Level III.

Background: Treatment for severe/relapsing Blount disease is controversial. The purpose of this study is to assess the safety and efficacy of acute medial plateau elevation with concurrent tibial gradual osteotomy., Methods: This study is a retrospective review of 16 patients (22 limbs) treated by combined plateau elevation and tibial osteotomy for the treatment of Blount disease. We measured the tibiofemoral angle, medial proximal tibial angle, and the plateau angle., Results: All measurements improved significantly preoperatively to postoperatively. The tibiofemoral angle from 29 degrees varus to 3 degrees of valgus, anatomic medial proximal tibial angle from 55 degrees to 86 degrees, and the plateau angle from 37 degrees to 12 degrees (P<0.05). Five patients were considered to have failed which appeared to be the result of undercorrection and subsequent recurrence of the tibial osteotomy and not the plateau elevation., Conclusions: The double osteotomy for Blount disease achieved significant improvement in all patients recurrence appeared to be because of under correction and subsequent worsening of the tibial osteotomy and not collapse of the plateau elevation., Level of Evidence: IV.

Background: Congenital anterolateral bowing of the tibia is a pre-pseudarthrosis stage of congenital pseudarthrosis of the tibia and is associated with a substantial risk of fracture and pseudarthrosis. We evaluated the results of prophylactic bypass grafting performed in combination with bracing to prevent fracture and pseudarthrosis., Methods: This retrospective series included ten patients with pre-pseudarthrosis of the tibia treated, between 1991 and 2002, with prophylactic bypass grafting with an allograft fibula placed posteromedially in a stress-bearing fashion. The average patient age was 2.3 years at the time of diagnosis, 3.6 years at the time of surgery, and ten years at the time of final follow-up. The mean duration of follow-up was seventy-eight months. Brace protection was recommended at the time of diagnosis and was continued after the operation until maturity. Despite the bracing, a low-energy fracture developed and partially healed prior to the bypass grafting in one patient. The remaining nine patients had no fractures prior to the bypass grafting. At the time of final follow-up, the patients were examined clinically and radiographically for the presence of a fracture or pseudarthrosis and for residual deformity, including malalignment, ankle and knee joint abnormalities, and leg length discrepancy., Results: No patient had either a fracture or a pseudarthrosis of the tibia at the time of follow-up. All grafts united to the tibia at both ends. Complications included an allograft fracture in three patients, which healed in all; allograft resorption in one patient; and pseudarthrosis of the ipsilateral host fibula in one patient. At the time of final follow-up, a mean of 9 mm (range, 0 to 37 mm) of leg length discrepancy was found. A corrective osteotomy was done for four patients (three because of ankle valgus and one because of diaphyseal deformity)., Conclusions: In this small series of ten patients with congenital anterolateral bowing of the tibia treated with bypass strut grafting and long-term bracing, there were no cases of pseudarthrosis of the tibia. Distal tibial deformity may persist throughout the growth period and require operative correction in patients treated with this procedure., Level of Evidence: Therapeutic Level IV. See Instructions to Authors for a complete description of levels of evidence.

This is a retrospective review of 25 tibial osteotomies (in 19 patients) performed with either acute or gradual correction to determine the outcome of treatment and incidence of neurovascular complications. Patients undergoing gradual correction had fewer neurovascular complications and greater correction than those undergoing acute correction (27 degrees vs. 18 degrees, respectively). It was concluded that gradual correction tends to be a safer technique for the treatment of tibial deformities and allows greater correction.

We report a 13-year-old girl with Ewing's sarcoma of the tibia who was treated with multiagent chemotherapy, followed by local control tumor surgery consisting of wide resection of the tumor and bone transport with distraction osteogenesis for reconstruction. The bone defect created by resection was 13 cm long and was replaced by bone transport using a monolateral external fixator. Evaluation of the resected specimen revealed wide tumor-free margins with 100% chemonecrosis. A planned Harmon-type autogenous bone grafting between the middle and proximal segments of the tibia (docking site) was done primarily after docking occurred, and a solid union was obtained by 23 months after resection. The bone healing index (treatment index) was 54 days/1 cm distraction, which is indicative of slow healing. Clinical evaluation of the affected extremity using the Musculoskeletal Tumor Society rating system revealed 80% normal functional capability. Indications for bone transport in reconstruction of bone defects created by wide resection of bone sarcomas are discussed. In retrospect, we have concerns regarding the suitability of this technique in the setting of diaphyseal sarcoma reconstruction in patients with Ewing's sarcoma who require aggressive and intense multiagent chemotherapy.

The purpose of this study was to assess distal femoral and tibial deformity in patients with infantile and adolescent Blount disease. This was a retrospective review of patients at the authors' institution diagnosed with Blount disease. Thirty-eight patients (21 in the infantile group and 17 in the adolescent group) met the study criteria. Measurements of the anatomic lateral distal femoral angle (aLDFA), anatomic lateral distal tibial angle (aLDTA), and tibiofemoral angle (TFA) were made from long-leg radiographs. The results of the infantile and adolescent measurements were compared with each other and to a normal database. Intraobserver and interobserver error was determined. The adolescent aLDFA measurements were significantly greater (more varus) than for the infantile group and normal database. The aLDTA (ankle) measurements were not statistically different between the two groups, or from the normal database. Analysis of both intraobserver and interobserver error for the aLDFA and aLDTA showed good reliability.

Summary: The authors hypothesized that the ratio of the femoral to tibial metaphyseal-diaphyseal angles (femoral-tibial ratio [FTR]) more accurately differentiates physiologic bowing from infantile tibial vara than the tibial metaphyseal-diaphyseal angle (TMDA). The purpose of this study was threefold: to determine the false-negative and false-positive error rate of the FTR and TMDA; to determine to the effect of rotation on the FTR and TMDA; and to determine the reliability of the FTR and TMDA measurements. An FTR < 1 resulted in a false-negative error rate of 10% and a false-positive error rate of 7%, whereas a TMDA > 13 degrees resulted in a false-negative error rate of 23% and a false-positive error rate of 10%. The difference between internal and external rotation was not significant for the FTR, whereas it was for the TMDA. The FTR was found to have good interobserver and intraobserver reliability (0.78 and 0.98, respectively).

Focal fibrocartilaginous dysplasia (FFCD) is an uncommon, benign condition associated with unilateral tibia vara in young children. The clinical, pathologic, plain film, and magnetic resonance imaging (MRI) findings of FFCD were reviewed in two children. MRI findings were virtually identical in both patients and correlated well with the plain film and pathologic findings. We believe that FFCD has a typical MRI appearance. However, FFCD also has characteristic plain film findings, and when these are present, MRI is indicated for only an atypical clinical presentation.