Background Many patients undergo both THA and spinal arthrodesis, and those patients may not fare as well as those who undergo one procedure but not the other. The mechanisms of how spinal arthrodesis affects patient function after THA remain unclear. Questions/purposes The aims of our study were to (1) determine how patient-reported outcome measures (PROMs), including the Oxford hip score as well as

Patellar maltracking occurs as a result of an imbalance in the dynamic relationship between the patella and trochlea. This is often secondary to an underlying structural abnormality. The clinical evaluation can provide useful clues for the presence of such entity; however, the diagnosis can often be challenging especially in the absence of a documented history of patellar dislocation. Imaging, particularly MRI, can detect subtle features that could lead to the diagnosis, probably even more importantly when there is no clear history of patellar dislocation or before its development. This can provide a road map for formulating a treatment strategy that would be primarily aimed at stabilizing the patellofemoral joint to halt or slow the progression of articular cartilage loss. The purpose of this article is to discuss the clinical and radiologic evaluation of patellar maltracking providing an update on the cross-sectional imaging assessment and also a synopsis of the management options.

Oedema in the superolateral portion of Hoffa's fat pad, the MRI feature of fat pad impingement, is associated with patellar maltracking.

Objectives: To evaluate image quality of two methods of registering MRI and CBCT images of the temporomandibular joint (TMJ), particularly regarding TMJ articular disc-condyle relationship and osseous abnormality. Methods: MR and CBCT images for 10 patients (20 TMJs) were obtained and co-registered using two methods (non-guided and marker guided) using Mirada XD software (Mirada Medical Ltd, Oxford, UK). Three radiologists independently and blindly evaluated three types of images (MRI, CBCT and registered MRI-CBCT) at two times (T 1 and T 2 ) on two criteria: (1) quality of MRI-CBCT registrations (excellent, fair or poor) and (2) TMJ disc-condylar position and articular osseous abnormalities (osteophytes, erosions and subcortical cyst, surface flattening, sclerosis). Results: 75% of the non-guided registered images showed excellent quality, and 95% of the marker-guided registered images showed poor quality. Significant difference was found between the non-guided and marker-guided registration (x 2 5 108.5; p , 0.01). The interexaminer variability of the disc position in MRI [intraclass correlation coefficient (ICC) 5 0.50 at T 1 , 0.56 at T 2 ] was lower than that in MRI-CBCT registered images [ICC 5 0.80 (0.52-0.92) at T 1 , 0.84 (0.62-0.93) at T 2 ]. Erosions and subcortical cysts were noticed less frequently in the MRI-CBCT images than in CBCT images. Conclusions: Non-guided registration proved superior to marker-guided registration. Although MRI-CBCT fused images were slightly more limited than CBCT alone to detect osseous abnormalities, use of the fused images improved the consistency among examiners in detecting disc position in relation to the condyle.