When evaluating a patient who has failed arthroscopic hip surgery, it is important to take a detailed history. It is important to identify the characteristics of pain that led to the first surgery and chronologic detail of the pain after that surgery. It is important to tease out if the pain is different in quality or intensity, whether there was a new trauma to the hip, or if the pain ever went away. Understanding the patients and their expectations and insight into their problem is an art that comes with experience but is vital in counseling and educating patients.

Physical exam should include a comprehensive evaluation of all possible causes of hip pain. This includes multi-positional musculoskeletal exam to evaluate gait, stance, core strength, lumbosacral spine pathology, pinpoint areas of maximal tenderness, hip range of motion, provocative maneuvers, weakness, and abnormal sensation or reflexes. It should also include a basic abdominal exam to rule out non-musculoskeletal causes of hip pain. We defer female pelvic exams, but if there is any question of a genitourinary cause of hip or groin pain, a referral to the gynecologist is initiated. Comprehensive review of the history and physical exam in this patient group are beyond the scope of this text, yet it is the opinion of the authors that these considerations are the best guides for selecting appropriate treatment for this patient group.

Postoperative changes can complicate the interpretation of imaging studies. Retained implants can cause distortion of MRI imaging decreasing the quality of the study. It is also challenging to identify clinically significant new findings in the postoperative hip.

Standard radiographic studies should include an AP pelvis, AP hip, and a lateral view of the hip (frog leg or cross table) [14]. These images should be scrutinized for pathology including cam and pincer impingement, hip arthritis, fracture, dysplasia, SI joint arthritis, and lumbar stenosis. Original imaging from before the initial surgery should be available for comparison.

MRI arthrogram should be the study of choice when evaluating for intra-articular soft tissue pathology in the postoperative hip. Blankenbaker et al. performed a retrospective review of 20 patients who had undergone revision arthroscopic hip surgery for recurrent labral tear after initially undergoing a labral debridement [15]. Original and postoperative MRI arthrograms, as well as surgical documentation of the revision procedure, were available for evaluation. All MRI arthrograms were obtained at the same institution using the same protocol. Two fellowship trained musculoskeletal radiologists reviewed the images retrospectively. Nineteen patients were diagnosed with recurrent labral tear intraoperatively. Fourteen tears were identified by consensus retrospective review on MRI arthrogram (12 based on high intensity line to the labral surface, two based on labral distortion and paralabral cyst formation). The other five patients were found to have only labral shortening. They concluded that a recurrent labral tear can be diagnosed on MRI arthrogram by the presence of a new high intensity line to the labral surface, an enlarged or distorted labrum, or a new paralabral cyst.

McCarthy and Glassner have shown the useful correlations between arthrography and arthroscopy in the revision setting [16]. We currently use a combination of MRI and MRI arthrogram to evaluate patients after hip arthroscopy when standard plain radiographs do not reveal the complete diagnosis. Figure 35.1 provides a summary of our most common uses for both studies.