An MRI-based Study to Investigate If the Patella is Truly Centred between the Femoral Condyles in the Coronal Plane.

Background: An AP knee radiograph is considered adequate if the patella is centred between the femoral condyles. Our previous studies demonstrated a tendency for lateral patellar deviation on an AP view orthogonal to the posterior femoral condyles. However, findings were based on cadaveric samples limited by the lack of soft tissue effects on patellar positioning. Materials and methods: After excluding those with deformity or damage to osseous or ligamentous structures, 106 knee MRI scans were randomly selected. Patellar centring was calculated as a percentage of total distal femoral intercondylar width and represented how lateral the centre of the patella is located with respect to the midpoint of the femoral condyles. Multiple regression analysis was performed to determine the relationship between patellar centring and age, gender, anatomic lateral distal femoral angle (aLDFA), medial proximal tibial angle (MPTA) and tibial tuberosity to trochlear groove (TT-TG) distance. Results: There were 35 males and 71 females included in the study with a mean age of 29 ± 14 years. Mean patellar centring was 8 ± 4%. There was a statistically significant correlation between TT-TG distance and positive (lateral) patellar centring (standardised ß = 0.36, p <0.01). There were no associations between aLDFA and MPTA with patellar centring. Conclusion: This study demonstrates that the patella is rarely perfectly centred and is usually positioned slightly laterally within the femoral condyles in an AP view orthogonal to the posterior aspect of the femoral condyles. The use of supine MRI scans makes this data relevant to a patient on the operating room table. How to cite this article: Shah NS, Kyriakedes JC, Liu RW. An MRI-based Study to Investigate If the Patella is Truly Centred between the Femoral Condyles in the Coronal Plane. Strategies Trauma Limb Reconstr 2022;17(2):63-67.

International Survey: Factors Associated With Operative Treatment of Distal Radius Fractures and Implications for the American Academy of Orthopaedic Surgeons' Appropriate Use Criteria.

OBJECTIVES: Through an international survey, we assessed whether deciding to operatively treat an intra-articular distal radius fracture (DRF) is guided by identifiable patient and surgeon factors. In addition, we compared surgeons' treatment decisions with the American Academy of Orthopaedic Surgeons' Appropriate Use Criteria (AUC) treatment recommendations. METHODS: This cross-sectional survey asked 224 surgeons to operatively or nonoperatively treat 28 hypothetical patients with radiographs of an intra-articular DRF. We randomized patient age (50/70 years), gender, mechanism of injury, activity level, and OTA/AO fracture type. We classified 6 fractures as "nonclinically significant displacement" and 22 as "potentially clinically significant displacement." Multilevel logistic regression analysis was performed. Odds ratios (ORs) and 95% confidence intervals (CIs) were reported. Statistical significance was P < 0.05. RESULTS: Patient factors independently associated with surgery included younger age (OR 6.7, P = 0.003), clinically significant fracture displacement (type B: OR 122, CI, 20-739, P < 0.001; type C: OR 59, CI, 12-300, P < 0.001), normal activity level (OR 5.0, P < 0.001), and high-energy mechanisms (OR 1.3, P = 0.002). Surgeon factors associated with recommending surgery included practicing outside the United States (Europe: OR 2.6, P < 0.001; "other": OR 4.8, P < 0.001). Hand surgeons most often selected surgery, as compared to orthopaedic trauma surgeons (OR 2.3, P = 0.001) and "other orthopaedists" (OR 2.2, P = 0.022). Thirty-seven percent of treatment decisions for patients with normal activity levels were rated by AUC recommendations as "rarely appropriate," which included 91% disagreement for 70-year-olds with nonclinically significant displacement. CONCLUSIONS: Surgeons use patient age and fracture displacement to make treatment recommendations for intra-articular DRF. We recommend that the AUC be updated to include these clinical factors as essential components in its algorithm. LEVEL OF EVIDENCE: Therapeutic Level V. See Instructions for Authors for a complete description of levels of evidence.

Type-V Median Nerve Entrapment in a Pediatric Medial Condyle Fracture: A Case Report.

CASE: A 30-month-old boy with a displaced medial condyle fracture and no history of an elbow dislocation was found to have an entrapped median nerve. CONCLUSION: Entrapment of the median nerve is a potential consequence of a displaced medial condyle fracture, even when there are no neurologic deficits on presentation. This provides additional support for open reduction of these fractures rather than percutaneous treatment or nonoperative management. Prompt identification and extraction of an interposed ulnar or median nerve is imperative to prevent the catastrophic consequences of an upper-extremity nerve palsy in children, as well as to optimize fracture-healing and elbow growth and development.

Distal Radius Fractures: AAOS Appropriate Use Criteria Versus Actual Management at a Level I Trauma Center.

BACKGROUND: The aim of this study is to determine whether the American Academy of Orthopaedic Surgeons' (AAOS) Appropriate Use Criteria (AUC) for distal radius fractures correlates with actual treatment by orthopedic hand surgeons at a level I trauma center. METHODS: ICD-9 codes were used to retrospectively identify patients who presented with wrist fractures over 1 year. Patients with isolated distal radius fractures were evaluated using the AAOS AUC application for distal radius fractures. Actual treatment was then compared with treatment recommended by the AUC. RESULTS: Of the 112 patients, 64 (57%) received treatment that matched the AAOS AUC recommendation as an "appropriate treatment." Actual management matched the AUC recommendation 100%, 7%, and 50% of the time, for Arbeitsgemeinschaft für Osteosynthesefragen/Orthopaedic Trauma Association (AO/OTA) type A, B, and C fractures, respectively. Surgery was performed for type A, B, and C fractures 30%, 7%, and 50% of the time, respectively. For type B fractures, only the 2 cases that were managed operatively were in agreement with the AUC. For type C fractures, increased patient age (57 years and older) was significantly associated with nonoperative treatment decisions. Surgeon decisions for nonoperative treatment were in agreement with the AUC recommendations 40% of the time, whereas surgeon decisions for surgery matched the AUC recommendations 97% of the time. CONCLUSIONS: We found low agreement between actual treatment decisions and the AUC-recommended "appropriate" treatments, especially for the type B and C fractures that were managed nonoperatively. The AUC favors surgery for all intra-articular fractures, while we emphasized age and fracture displacement in our decision-making process.

An Anatomic Study on Whether the Immature Patella is Centered on an Anteroposterior Radiograph.

BACKGROUND: In the operating room, after first obtaining a proper lateral radiograph with the condyles superimposed, a 90-degree rotation of the intraoperative fluoroscopy unit does not always produce an anteroposterior (AP) image with the patella centered. The orthogonality of these 2 views has not been well determined in children. METHODS: This study was comprised of a radiographic group (35 knees) and a cadaveric group (59 knees). Both cadaveric and clinical images were obtained by resting or positioning the femur with the posterior condyles overlapped, and then taking an orthogonal AP image. Centering of the patella was calculated and multiple regression analysis was performed to determine the relationship between patellar centering and age, sex, ethnicity, mechanical lateral distal femoral angle (mLDFA), medial proximal tibial angle (MPTA), and contralateral centering. RESULTS: Mean patellar centering, expressed as the lateral position of the patella with respect to the total condylar width, was 0.08±0.10 in the radiographic group and 0.06±0.03 in the cadaveric group. Positive (lateral) patellar centering in 1 knee had a statistically significant correlation with positive patellar centering in the contralateral knee in both the radiographs and the cadavers. In the radiographic group, there was a statistically significant correlation between femoral varus and valgus deformities and positive patellar centering. In the cadaveric group, there was a statistically significant correlation between tibial valgus and negative (medial) patellar centering. CONCLUSION: The patella in an immature knee is rarely perfectly centered on a true AP image, and is usually seated slightly laterally within the femoral condyles. CLINICAL RELEVANCE: Obtaining a true AP intraoperative radiograph is critical to analyzing and correcting valgus and varus deformities, and in the proper placement of implants. When addressing knee deformity one should consider obtaining an AP view orthogonal either to a perfect lateral of the knee or orthogonal to the flexion axis of the knee, particularly when evaluating distal femoral deformity.