Femoroacetabular Impingement: Radiographic Diagnosis—What the Radiologist Should Know

Abstract

Femoroacetabular impingement is a major cause for early "primary" osteoarthritis of the hip. It can easily be recognized on conventional radiographs of the pelvis and the proximal femur.

The prevalence of radiographic femoroacetabular impingement in younger individuals undergoing total hip replacement for osteoarthritis

“…One limitation of our study's retrospective design was the inability to assure standardized technique and views for the radiographs assessed. This is important since incorrect positioning or radiographic technique may affect the accuracy of interpretation [6]. In addition, the lack of lateral view radiographs for 23 of the 75 (31 %) eligible subjects made it difficult to discern cam impingement features.…”

“…Two radiologists assessed radiographs using a scoring tool based on a literature review [6,[9][10][11] (Tables 1 and 2). Each subject was categorized into one of three groups: definite FAI, no FAI, or not possible to exclude FAI.…”

“…Cam impingement is more commonly found in younger athletic males, while pincer impingement occurs typically in middle-aged females [3,5]. Often, patients present with features of both impingement types [6].…”

“…The clinical findings include groin pain associated with hip rotation, sitting position, or sports activities or limited range of motion [6]. On physical examination, a positive "impingement test" reproduces the groin pain when the hip is flexed to 90 ° with internal rotation and adduction [6].…”

“…The clinical findings include groin pain associated with hip rotation, sitting position, or sports activities or limited range of motion [6]. On physical examination, a positive "impingement test" reproduces the groin pain when the hip is flexed to 90 ° with internal rotation and adduction [6]. Although most orthopedic centers in North America and Europe offer surgical options for FAI to address hip pain [8], there are limited data on the epidemiology of FAI.…”