The effect of tibial rotation on varus deformity measurement.

PURPOSE: Tibial osteotomy is used to treat a variety of orthopedic conditions, including reduction in pain and improvement of deformity and function. In templating for surgery, accurate radiographic measurement aids in planning for correction. The purpose of our study was to examine the effect of internal rotation and external rotation on measurement of tibial sawbone models with 5 closing wedge varus deformities at 10-degree increments between 10 and 50 degrees. One sawbone without deformity served as the control. STUDY DESIGN: A total of 66 radiographs were measured by 5 individuals. Measurement deviations from the control in each of the 10 positions of rotation were assessed. RESULTS: In the analysis of variance models, increased rotation and varus angulation were associated with increased deviation compared with the control. In external rotation for every 10 degrees of varus angulation, the degree deviation increased 0.69 degrees. In IR for every 10 degrees of angulation, the degree deviation increased by 0.84 degrees. Internal rotation had the greatest impact. Mean differences between different rater's measurements were small (1.1+/-1.2 degrees) and correlations suggested high interrater reliability. CONCLUSIONS: As the degree of rotation from neutral increased and varus angulation increased, deviation from neutral increased. CLINICAL RELEVANCE: Clinically, the results of this study support the importance of proper alignment of the tibia during radiography to more precisely template surgery.

Slipped capital femoral epiphysis: physeal histologic features before and after fixation.

Physeal histopathologic changes following slipped capital femoral epiphysis (SCFE) are usually considered permanent. This assumption may not be correct, since radiographic signs of proximal femoral neck growth and remodeling are commonly seen after fixation. This work analyzed the physeal histologic features of chondroepiphyseal biopsies before and after SCFE surgical fixation but before complete physiologic epiphysiodesis. Eighteen patients, nine with unstable and nine with stable SCFE of varying severity, had pretreatment biopsies. Three patients had postfixation biopsies prior to total physiologic proximal femoral epiphysiodesis. Pretreatment biopsies showed varied degrees of histoarchitectural changes ranging from almost normal arrangement to markedly deranged physeal morphology. Postfixation biopsies showed improved physeal organization in a case of moderate unstable SCFE. In one severe unstable case and one severe stable case, nearly normal physeal architecture was seen. Physeal histopathologic changes appear to improve after fixation. Progressive modulation of the recovering physis after fixation helps explain the remodeling and growth changes seen radiographically after chondroepiphyseal fixation.

Fibular hemimelia: a new classification system.

A new classification system for fibular hemimelia is proposed based on the authors' experience with 32 patients with 33 involved limbs representing a spectrum of involvement. The data demonstrate the broad and unpredictable relationships among the fibula, ankle, and foot in this disorder. The classification system, based on fibular and ankle morphology, hindfoot coalition, and foot ray deficits, is designed to improve communication about the condition. Because of the variability and unpredictability of the multiple relationships, limb salvage criteria should also include the nature of the foot and ankle and not merely depend on the length discrepancy or the presence or absence of the fibula.