The effect of pelvic ring rotation and tilt on the radiographic teardrop distance: an important consideration in the assessment of dynamic displacement on stress radiographs.

PURPOSE: The purpose of this study was to determine the effect of rotation and tilt on the radiographic teardrop distance (TD) on anteroposterior (AP) pelvis radiographs. METHODS: Radiographic examination of a pelvis models was conducted utilizing increasing degrees of beam rotation and tilt on portable C-arm fluoroscopy. The TD, x-plane rotation (symphyseal-mid-sacrum distance (SMS)), and y-plane tilt (sacroiliac joint-symphysis distance (SIS)) were measured by four independent observers. Interobserver reliability was assessed using intraclass correlations. RESULTS: TD was altered by less than 2 mm with up to 7.5° fluoroscopic rotation (SMS: 3 cm) and up to 30° of inlet and 15° of outlet (SIS: ± 3.3 cm). SMS distance effectively corresponded to the degree of rotation present (r = 1.00, CI: 0.97 to 1.00, p < 0.0001) and was strongly correlated to TD (r = -0.95, CI: -0.99 to -0.67, p = 0.001). SIS distance effectively corresponded to the degree of tilt present (r = -0.97, CI: -0.99 to -0.88, p < 0.0001) and was correlated to TD (r = 0.94, CI: 0.75 to 0.99, p = 0.0001). Linear regression models determined that, with every degree of rotation and tilt, TD was altered by 0.4 mm and 0.09 mm, respectively (p = 0.0004, r2 = 0.93 and p < 0.0001, r2 = 0.94, respectively). Interobserver reliability among observers was excellent (0.92). CONCLUSION: The TD has excellent interobserver reliability and is minimally impacted by up to 7.5° of rotation, 30° inlet tilt, and 15° of outlet tilt. Utilization of these thresholds may ensure reliability of TD measurements when assessing pelvis stress radiographs.

Intramedullary Implant Choice and Cost in the Treatment of Pediatric Diaphyseal Forearm Fractures.

OBJECTIVES: To compare outcomes and costs between titanium elastic nails (TENs), stainless steel elastic nails (SENs), and Kirschner wires (K-wires) in the treatment of pediatric diaphyseal forearm fractures with intramedullary fixation. DESIGN: Retrospective cohort study. SETTING: Level 1 Pediatric Trauma Center. PATIENTS/PARTICIPANTS: A total of 100 patients (65 male and 35 female) younger than 18 years with diaphyseal forearm fractures treated with intramedullary fixation were included in the study. INTERVENTION: Patients received single or both bone intramedullary fixation with either TENs, SENs, or K-wires. MAIN OUTCOME MEASUREMENTS: Time to radiographic union, complication rate, surgical time, and average cost per implant. RESULTS: One hundred patients were included in the study. Thirty-one patients were treated with TENs, 30 with SENs, and 39 with K-wires. No significant difference in time to radiographic union, complication rate, or surgical time was found between the 3 types of fixation. Average time to union was 9.4 ± 5.4 weeks, and complication rate was 12.9% for TENs, 10.0% for SENs, and 12.8% for K-wires. There was a significant difference in cost per implant, with an average cost of $639, $172, and $24 for TENs, SENs, and K-wires, respectively (P < 0.001). CONCLUSIONS: This study demonstrates no difference between TENs, SENs, and K-wires in the treatment of pediatric diaphyseal forearm fractures with regards to outcome, time to union, surgical time, or complication rates. Given the significant cost difference between these implants, we recommend that surgeons consider modifying their implant selection to help mitigate cost. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Delay to Reconstruction of the Adolescent Anterior Cruciate Ligament: The Socioeconomic Impact on Treatment.

BACKGROUND: A delay in pediatric and adolescent anterior cruciate ligament (ACL) reconstruction is associated with an increase in the number of concomitant meniscal and chondral injuries. Factors that contribute to this delay have not been well described. HYPOTHESIS: Socioeconomic and demographic factors are related to ACL surgery timing. STUDY METHODS: Cohort study; Level of evidence, 3. METHODS: All subjects who underwent primary ACL reconstruction at a single tertiary pediatric hospital between 2005 and 2012 were retrospectively reviewed. Variables included concomitant knee injuries (cartilage or meniscus injuries requiring additional operative treatment) and chronologic, demographic, and socioeconomic factors. Multivariable Cox proportional-hazards analyses were used to identify factors related to ACL surgery timing. RESULTS: The mean age of the 272 subjects was 15.2 ± 2.12 years. Time to surgery was significantly different among subjects who required multiple additional surgical procedures at time of ACL reconstruction (median, 3.3 months) compared with subjects with 1 (median, 2.0 months) or no additional injuries (median, 1.6 months). Subjects underwent ACL reconstruction significantly sooner if they were older at the time of injury (hazard ratio [HR], 1.2 per 1 year; 95% CI, 1.1-1.2; P < .0001) or were covered by a commercial insurance plan (HR, 2.0; 95% CI, 1.6-2.6; P < .0001). Median time to ACL surgery was 1.5 months (95% CI, 1.3-1.7) for subjects with commercial insurance plans compared with 3.0 months (95% CI, 2.3-3.3) for subjects with noncommercial insurance coverage. CONCLUSION: The risk of delayed ACL surgery was significantly higher among pediatric and adolescent subjects who were less affluent, who were covered by a noncommercial insurance plan, and who were younger. This study also confirms previous studies that have reported an association between a delay in ACL surgery and the presence of additional knee injuries requiring operative treatment, accentuating the importance of timely care. CLINICAL RELEVANCE: Access to care is a current area of research interest and health policy formation. Information in this arena drives 2 important aspects of health: most immediately, care provided to patients, and over a broader scope, the policy that directs health care. The orthopaedic surgeon should be aware of the association between socioeconomic and demographic factors and ACL surgery timing to optimize outcomes.