Prevalence of lateral patellofemoral maltracking and associated complications in patients with Osgood Schlatter disease.

OBJECTIVE: To evaluate adults with history of Osgood Schlatter disease (OSD) for imaging features of lateral patellofemoral maltracking. METHODS: In a span of four years, 10,181 unique non-contrast knee MRIs were performed on patients aged 20-50. Patients with acute trauma, prior surgery, and synovial pathologies were excluded. 171 exams had imaging findings of OSD, and an age-matched control group of 342 patients without OSD was randomly selected. Two radiologists retrospectively reviewed MRIs for features of lateral patellofemoral maltracking. Maltracking was defined as edema in superolateral Hoffa's fat or a tibial tuberosity-trochlear groove (TT-TG) distance ≥20 mm with either patellar tilt/translation. Binomial logistic regression identified predictors of maltracking in OSD. Optimal TT-TG distance to indicate maltracking was determined by receiver operating characteristic curve. RESULTS: 59% (101/171) of the knees with OSD showed findings of maltracking, with patella alta, trochlear dysplasia, and quadriceps tendinosis as significant predictors of maltracking (p < 0.001). Patellofemoral chondrosis was present in 63% (107/171), with maltracking contributing to higher grade chondrosis more so than increasing age (OR 8.4 versus 1.07). 13 mm was the optimal cut-off TT-TG distance to indicate maltracking (sensitivity 83%, specificity 80%). The prevalence of maltracking in the control group was 15% (p < 0.001 compared with the OSD group). CONCLUSION: Adults with sequelae of OSD are at high risk of maltracking and are likely to develop patellofemoral chondrosis. A lower threshold for identifying maltracking patients, including a lower cut-off TT-TG distance can help identify those at risk. Radiologists should maintain a high index of suspicion for maltracking in adults with OSD to guide clinical intervention.

Postoperative MR Imaging of the Pubic Symphysis and Athletic Pubalgia.

MR imaging evaluation can be valuable in patients with prior surgery for athletic pubalgia presenting with new, recurrent, or persistent groin pain. The clinical and interventional history as well as comparison with preoperative imaging is essential for imaging interpretation. Imagers should be aware of expected and unexpected postoperative findings. MR imaging findings concerning for infection, new injury, contralateral injury, or concomitant sources of symptoms (such as hip pathology) should be reported when present.

Comparative Trends in Utilization of MRI and Ultrasound to Evaluate Nonspine Joint Disease 2003 to 2015.

PURPOSE: MRI and ultrasound (US) are effective diagnostic tools to evaluate extremities. In this study, we analyze utilization trends in musculoskeletal (MSK) US and MRI from 2003 to 2015 within the Medicare population. METHODS: Our data sources were the Medicare Part B Physician/Supplier Procedure Summary Master Files for 2003 to 2015. They cover all Medicare fee-for-service enrollees (37.5 million in 2015). Current Procedural Terminology codes for nonvascular, nonspine joint MRI and extremity US were selected and volumes within these codes were determined. Medicare's physician specialty codes were used to identify provider specialty. We accounted for the 2011 code change that created both complete and limited US examinations. RESULTS: Total Medicare joint MRI volume increased from 738,509 in 2003 to 1,131,503 in 2015 (+53%), although there was little change after 2007. Radiologist MRI share in 2015 was 93%, followed by orthopedic surgeons at 5%. Total MSK US volume grew from 96,235 in 2003 to 429,695 in 2015 (+347%). Radiologists' market share of US decreased from 65% in 2003 to 37% in 2015, with nonradiologists now representing a majority of ultrasound examinations. Multiple nonradiology subspecialties also exceed radiology in volume of complete ultrasounds. CONCLUSION: The potential negative impact of MSK US on MSK MRI volume is likely overestimated because MRI volume has remained stable. MSK ultrasound is increasingly utilized outside radiology. If radiologists want to maintain their market share as MSK imaging leaders, more emphasis should be placed on increasing their involvement and expertise in MSK US.