Abstract
Osteoarthritis (OA) of the hip is caused by degeneration of articular cartilage and
the underlying bone and can be divided into two types: primary (associated with advancing
age) and secondary (subsequent to fractures, avascular necrosis, infection, developmental
dysplasia, and femoroacetabular impingement). Radiography remains the first-line imaging
modality for diagnosing and monitoring OA, due to its accessibility, low cost, and
ease of interpretation. Kellgren-Lawrence and Tönnis classification systems are radiographic
OA grading systems used primarily in research, and they reflect the degree of joint
space narrowing, sclerosis, cysts, deformity of the femoral head and acetabulum, and
osteophytes. Unenhanced computed tomography (CT) provides detailed visualization of
the hip joint segments that may be difficult to appreciate on radiographs, such as
the inferoposterior and posterolateral hip joint. CT arthrography, magnetic resonance
imaging (MRI), and magnetic resonance arthrography with two-dimensional reconstructions
can delineate labral abnormalities, cartilage lesions, and other intra-articular hip
pathology. T2 and T2* mapping, delayed gadolinium-enhanced MRI of cartilage, T1rho,
ultra-short echo time, and zero echo time are investigative MR techniques with promising
evaluation of hip OA.
Keywords
hip - osteoarthritis - radiographs - computed tomography - magnetic resonance imaging
- ultra-short echo time
