JAAOS, Volume 16, No. 5

Isolated acetabular liner exchange.

During the past two decades, most total hip arthroplasties were performed with metal or ceramic heads on conventional polyethylene, an articulation associated with wear and limited life expectancy. Wear is associated with acetabular osteolysis. Isolated liner exchange has become a common surgical intervention when the acetabular component remains well-fixed. The purpose of isolated liner exchange is to prevent loosening of the components secondary to osteolysis and catastrophic mechanical failure caused by bearing wear-through. Treatment options for polyethylene wear include observation (in the asymptomatic hip), liner exchange, and more extensive revision procedures. Patients frequently present with asymptomatic but substantial polyethylene wear with or without associated osteolysis, the treatment of which is controversial. Other areas of debate include complete acetabular component removal to allow bone grafting and placement of an improved bearing surface, reuse of modular mechanisms, cementation into well-fixed shells, and whether to use periacetabular bone grafting.

    • Keywords:
    • Acetabulum|Arthroplasty

    • Replacement

    • Hip|Bone Transplantation|Cementation|Equipment Failure Analysis|Hip Prosthesis|Humans|Osteolysis|Physical Therapy Modalities|Polyethylene|Prosthesis Design|Prosthesis Failure|Reoperation

    • Subspecialty:
    • Basic Science

    • Adult Reconstruction

Osteoarthritis of the ankle: the role of arthroplasty.

Total ankle arthroplasty was developed to reduce pain and retain motion of the ankle joint in patients with osteoarthritis. The ankle joint has unique, complex anatomic and biomechanical characteristics that must be considered in a successful total ankle arthroplasty prosthesis. Initial designs from the 1960s to the 1970s had many failures. Current designs use two or three components, and recent reports on total ankle arthroplasty show consistent good to excellent intermediate clinical results, with up to 90% decreased pain and high patient satisfaction. The follow-up time of these studies is limited, however, and long-term studies with 10- to 15-year follow-ups are needed. Also, a wide variety of complications has been reported, including osteomyelitis and osteolysis. To limit the number of complications and improve clinical outcome of total ankle arthroplasty, careful patient selection and surgeon experience are important.

    • Keywords:
    • Ankle Joint|Arthroplasty|Biomechanics|Bone Transplantation|Debridement|Humans|Osteoarthritis|Postoperative Complications|Prosthesis Design|Transplantation

    • Homologous|Treatment Outcome

    • Subspecialty:
    • Foot and Ankle

    • Pain Management

The FDA process for the evaluation and approval of orthopaedic devices.

The US Food and Drug Administration (FDA) is a scientific, regulatory, and public health agency whose authority includes overseeing the marketing of products relevant to medical practice. Devices are classified based on the extent of oversight needed to ensure public safety. Divisions within the FDA provide specific expertise regarding drugs, devices, biologic products, and combinations thereof. Various pathways exist to apply for marketing through the FDA, depending on the nature of the product and its intended use. Expert panels advise the agency on issues related to product safety and efficacy, and clinical studies may be required to provide data based on these parameters. Clinical data are monitored postapproval for potential adverse events not evident in earlier trials. Orthopaedic surgeons are involved in all aspects of the FDA as employees, consultants, product advocates, participants in clinical trials and advisory panels, and experts involved in the appropriate reporting of adverse events.

    • Keywords:
    • Advisory Committees|Consumer Product Safety|Device Approval|Expert Testimony|Humans|Marketing|Orthopedic Equipment|Orthopedics|Physicians Role|Product Surveillance

    • Postmarketing|United States|United States Food and Drug Administration

    • Subspecialty:
    • Clinical Practice Improvement

Benign synovial disorders.

Collectively, benign synovial disorders are not uncommon, and they may be seen in general orthopaedic practices. Symptoms are nonspecific, often delaying diagnosis. In fact, synovial chondromatosis, pigmented villonodular synovitis, synovial hemangioma, and lipoma arborescens often mimic each other as well as other, more common joint disorders in presentation, making diagnosis extremely difficult. It is important to diagnose these disorders correctly in order to provide appropriate treatment and avoid secondary sequelae, such as bone erosion and cartilage degeneration.

    • Keywords:
    • Chondromatosis

    • Synovial|Diagnosis

    • Differential|Hemangioma|Humans|Joint Loose Bodies|Lipoma|Magnetic Resonance Imaging|Soft Tissue Neoplasms|Synovial Membrane|Synovitis

    • Pigmented Villonodular|Tomography

    • X-Ray Computed

    • Subspecialty:
    • General Orthopaedics

    • Sports Medicine

Acute carpal tunnel syndrome.

Carpal tunnel syndrome is considered the most common of the chronic compressive neuropathies. Its cause is generally unknown. Acute carpal tunnel syndrome, which is much less common, is more often directly related to fractures and fracture-dislocations about the wrist, hemorrhagic conditions, and vascular disorders involving the wrist. Many rare and unusual causes have been described, including chronic conditions that may be associated with acute carpal tunnel syndrome, such as rheumatologic disorders and anomalous anatomy. In contrast to the more common chronic idiopathic form, the acute form of carpal tunnel syndrome requires urgent surgical intervention to avoid or diminish serious sequelae.

    • Keywords:
    • Acute Disease|Carpal Tunnel Syndrome|Dislocations|Fractures

    • Bone|Humans|Wrist Injuries|Wrist Joint

    • Subspecialty:
    • Hand and Wrist

Prophylactic antibiotics in orthopaedic surgery.

The use of prophylactic antibiotics in orthopaedic surgery is effective in reducing surgical site infections in hip and knee arthroplasty, spine surgery, and open reduction and internal fixation of fractures. To maximize the beneficial effect of prophylactic antibiotics while minimizing adverse effects, the correct antimicrobial agent must be selected, the drug must be administered just before incision, and the duration of administration should not exceed 24 hours.

    • Keywords:
    • Anti-Bacterial Agents|Antibiotic Prophylaxis|Cephalosporins|Drug Hypersensitivity|History

    • 19th Century|History

    • 20th Century|Humans|Methicillin Resistance|Orthopedic Procedures|Orthopedics|Surgical Wound Infection|Vancomycin

    • Subspecialty:
    • Foot and Ankle

    • Trauma

    • Spine

    • Clinical Practice Improvement