MR-based Bony 3D models enable radiation-free preoperative patient-specific analysis and 3D printing for SCFE patients.

Objectives: Slipped capital femoral epiphyses (SCFE) is a common pediatric hip disease with the risk of osteoarthritis and impingement deformities, and 3D models could be useful for patient-specific analysis. Therefore, magnetic resonance imaging (MRI) bone segmentation and feasibility of 3D printing and of 3D ROM simulation using MRI-based 3D models were investigated.

Methods: A retrospective study involving 22 symptomatic patients (22 hips) with SCFE was performed.

Hip Impingement of severe SCFE patients after in situ pinning causes decreased flexion and forced external rotation in flexion on 3D-CT.

Introduction: In situ pinning is an accepted treatment for stable slipped capital femoral epiphysis. However, residual deformity of severe slipped capital femoral epiphysis can cause femoroacetabular impingement and forced external rotation.

Purpose/questions: The aim of this study was to evaluate the (1) hip external rotation and internal rotation in flexion, (2) hip impingement location, and (3) impingement frequency in early flexion in severe slipped capital femoral epiphysis patients after in situ pinning using three-dimensional computed tomography.

Do Osteochondroplasty Alone, Intertrochanteric Derotation Osteotomy, and Flexion-Derotation Osteotomy Improve Hip Flexion and Internal Rotation to Normal Range in Hips With Severe SCFE? - A 3D-CT Simulation Study.

Background: Severe slipped capital femoral epiphysis (SCFE) leads to femoroacetabular impingement and restricted hip motion. We investigated the improvement of impingement-free flexion and internal rotation (IR) in 90 degrees of flexion following a simulated osteochondroplasty, a derotation osteotomy, and a combined flexion-derotation osteotomy in severe SCFE patients using 3D-CT-based collision detection software.

Methods: Preoperative pelvic CT of 18 untreated patients (21 hips) with severe SCFE (slip-angle>60 degrees) was used to generate patient-specific 3D models.

Limited Hip Flexion and Internal Rotation Resulting From Early Hip Impingement Conflict on Anterior Metaphysis of Patients With Untreated Severe SCFE Using 3D Modelling.

Introduction: Slipped capital femoral epiphysis (SCFE) is the most common hip disorder in adolescent patients that can result in complex 3 dimensional (3D)-deformity and hip preservation surgery (eg, in situ pinning or proximal femoral osteotomy) is often performed. But there is little information about location of impingement.Purpose/Questions: The purpose of this study was to evaluate (1) impingement-free hip flexion and internal rotation (IR), (2) frequency of impingement in early flexion (30 to 60 degrees), and (3) location of acetabular and femoral impingement in IR in 90 degrees of flexion (IRF-90 degrees) and in maximal flexion for patients with untreated severe SCFE using preoperative 3D-computed tomography (CT) for impingement simulation.

The incidence and risk factors for stress fracture following periacetabular osteotomy.

Aims: The aims of this study were to characterize the incidence and risk factors associated with stress fractures following periacetabular osteotomy, and to determine their effect on osteotomy union.

Methods: We retrospectively reviewed all periacetabular osteotomies (PAOs) performed for developmental dysplasia of the hip (DDH) at one institution over a six-year period between 2012 and 2017. Perioperative factors were recorded, and included demographic and surgical data.

Does the Capital Femoral Physis Bony MorphologyDiffer in Children with Symptomatic Cam-type Femoroacetabular Impingement.

Background: The epiphyseal tubercle, the corresponding metaphyseal fossa, and peripheral cupping are key stabilizers of the femoral head-neck junction. Abnormal development of these features in the setting of supraphysiologic physeal stress under high forces (for example, forces that occur during sports activity) may result in a cam morphology. Although most previous studies on cam-type femoroacetabular impingement (FAI) have mainly focused on overgrowth of the peripheral cupping, little is known about detailed morphologic changes of the epiphyseal and metaphyseal bony surfaces in patients with cam morphology.

What Proportion of Patients Undergoing Bernese Periacetabular Osteotomy Experience Nonunion, and What Factors are Associated with Nonunion?

Background: The Bernese periacetabular osteotomy (PAO) is one of the most-used surgical techniques to treat symptomatic acetabular dysplasia. Although good functional and radiographic short-term and long-term outcomes have been reported, several complications after PAO have been described. One complication that may compromise clinical results is nonunion of an osteotomy.

What Is the Accuracy and Reliability of the Peritubercle Lucency Sign on Radiographs for Early Diagnosis of Slipped Capital Femoral Epiphysis Compared With MRI as the Gold Standard?

Background: The diagnosis of slipped capital femoral epiphysis (SCFE) often is delayed. Although lack of clinical suspicion is the main cause of delayed diagnosis, typical radiographic changes may not be present during the initial phases of SCFE. The peritubercle lucency sign for follow-up of the contralateral hip in patients with unilateral SCFE may be beneficial in assisting the early diagnosis.

Morphologic Features of the Contralateral Femur in Patients With Unilateral Slipped Capital Femoral Epiphysis Resembles Mild Slip Deformity: A Matched Cohort Study.

Background: Hip osteoarthritis has been reported in the contralateral hip in patients who had been treated for unilateral slipped capital femoral epiphysis (SCFE) during adolescence. Although this might be related to the presence of a mild deformity, the morphologic features of the contralateral hip in unilateral SCFE remains poorly characterized.

Questions/purposes: Do measurements of (1) femoral head-neck concavity (α angle and femoral head-neck offset), (2) epiphyseal extension into the metaphysis (epiphyseal extension ratio and epiphyseal angle), and (3) posterior tilt of the epiphysis (epiphyseal tilt angle) differ between the contralateral asymptomatic hips of patients treated for unilateral SCFE and hips of an age- and sex-matched control population without a history of hip disease?

Methods: From January 2005 to May 2015, 442 patients underwent surgical treatment for SCFE at our institution.