Imaging in the Recognition and Treatment of Lesions Predisposing to Osteoarthritis

Osteoarthritis is the most common form of arthritis and a leading cause of disability. The etiology of osteoarthritis is complex. Numerous risk factors for the development or progression of osteoarthritis have been identified including age, obesity, congenital or acquired joint deformity, injury, genetic predisposition, occupational or physical activity, and many others. The treatment options for established osteoarthritis have been largely limited to behavior modification, physical therapy, symptom relief with pharmaceuticals, joint injections, arthroscopy, osteotomy, and, in the end-stage, joint replacement. For this reason, there is an emphasis on prevention through intervention prior to the development of osteoarthritis. Imaging techniques, from radiography to advanced MR acquisition techniques, continue to be important tools for treatment decision making in this field.

The purpose of this issue of Seminars in Musculoskeletal Radiology is to demonstrate the pivotal role imaging can play in the diagnosis of conditions and injuries predisposing to osteoarthritis and in the evaluation of joints following surgical intervention. It would require a truly comprehensive publication to present all of the conditions where imaging and surgical interventions are used to improve the prognosis for a joint. Since the issue cannot be exhaustive, we have chosen a few examples that illustrate the variety of imaging techniques that are currently employed for pre- and post-operative evaluation. Some common injuries, such as cruciate ligament tears, have been extensively presented in other articles and are not included to present some less commonly discussed conditions and to illustrate newer imaging techniques.

Since cartilage injury and degeneration are hallmarks of osteoarthritis, the issue starts with a discussion, by Dr. Alparslan and myself, of the mechanisms of cartilage injury and techniques for cartilage assessment including MR imaging and CT-arthrography. Chronic repetitive and acute cartilage injuries are presented through examples in the hip, knee, and ankle.

The next article, by Dr. Domayer et al, is from one of the leading research groups in surgical techniques for articular cartilage repair. They review the current status of cartilage repair in the knee and the role of MR imaging in the assessment of joint following cartilage repair surgery using both standard and biochemical imaging techniques.

Drs. Huysee, Verstraete, Verdonk, and Verdonk are leaders in the evaluation and treatment of the knee meniscus, and they have contributed an excellent review of this structure and its important role in the protection of the knee joint from osteoarthritis. A description of the composition, function, surgical treatment and transplantation of the meniscus is combined with a thorough discussion of the imaging of the native and transplanted meniscus.

The fourth article reviews the radiographic and MR findings of structural abnormalities of the hip. Drs. Kim, Bixby, Mamisch, Clohisy, and Carlisle highlight the use of imaging for preoperative surgical decision making. The authors provide a practical reference that I hope you find useful when interpreting hip images for suspected impingement or dysplasia.

In the next article, Drs. Alparslan and Chiodo discuss chronic lateral ankle instability and its surgical treatment. They demonstrate the MR appearance of associated injuries and the surgical treatment procedures. The diagrams and MR case examples of the various ligament reconstruction procedures are invaluable when reviewing postoperative images.

The final article, by Drs. Tanaka, Ogino, and Yoshioka, discusses ligamentous injuries of the wrist. High resolution MR imaging of the intrinsic ligaments of the wrist are used to demonstrate the anatomy and appearance of ligament tears. The arthroscopic and open surgical procedures for these injuries are discussed in light of the structural abnormalities important for treatment decisions.

I am grateful to the authors of these superb articles for their contributions to this issue. Through much hard work, these knowledgeable authorities have provided us with important insights from their extensive clinical experience. I hope that you find them as enjoyable and useful as I have in understanding the role of imaging in the treatment of these musculoskeletal disorders.