Faculty Bibliography

The purpose of this gallery of orthopedic implants was to provide a reference for emergency radiologists to quickly identify uncommon devices in the shoulders, hips, and extremities. The cases presented in this exhibit will include unusual arthroplasties and prostheses as well as bone graft implants (including allograft and autograft). Bone grafts are frequently used for the treatment of bone defects, which may be caused by trauma, infection, or avascularity. Autogenous cancellous, corticocancellous, or cortical bone grafts are often used, either free or vascularized. Alternative bone graft substitutes are also used. An obvious complication of bone grafts is the failure of incorporation. Joint arthroplasty is the most frequently performed orthopedic procedure after fracture fixation. Major indications include degenerative joint disease, inflammatory arthropathy, avascular necrosis, and complicated fractures. Custom orthopedic implants are frequently used for less common indications or for patients with bone tumors. The common hardware complications are infections, loosening, small particle disease/osteolysis, periprosthetic fracture, hardware fracture or dislocation, and recurrent disease, especially in patients with tumors. Many of the devices used by orthopedic surgeons are infrequently seen in everyday radiology practice. With such variations, correct recognition of the prosthetic devices and their complications is very important. The goal of this exhibit was to familiarize the radiologist with both the normal and abnormal appearance of many atypical orthopedic implants. It is important to understand the purpose and proper function of a device, but not necessarily important to describe every device by its proper brand name. Although this exhibit is not meant to be inclusive of every unusual orthopedic implant, we will present multiple examples of orthopedic hardware involving the shoulder, humerus, elbow, forearm, wrist, hand, pelvis, hip, femur, knee, tibia, ankle, and foot that are not likely seen in everyday practice.

Septic arthritis is a disabling and possibly life-threatening disease that requires early diagnosis for optimal management. It is important that clinical and imaging features of septic arthritis be promptly identified. In addition, because other disease entities may have characteristics similar to those of septic arthritis, analysis of a needle biopsy specimen may be necessary for differential diagnosis. Radiologists may be asked to perform emergent aspiration of a possibly infected joint. It is important that those who perform aspiration procedures be familiar with a safe and effective imaging-guided arthrocentesis technique that is tailored to the individual patient and the specific joint affected.

The knee is an intricate joint with numerous tendinous, ligamentous, and meniscal attachments, which make it particularly vulnerable to complex injuries after trauma. A variety of avulsion fractures of the knee can occur, including Segond and reverse Segond fractures; avulsions of the anterior and posterior cruciate ligaments; arcuate complex avulsion; iliotibial band avulsion; avulsions of the biceps femoris, semimembranosus, and quadriceps tendons; Sinding-Larsen-Johansson syndrome; and Osgood-Schlatter disease. These fractures often have a subtle appearance at conventional radiography, which is typically the first imaging modality performed in these cases. Advanced imaging modalities, particularly magnetic resonance imaging, are helpful and can provide valuable additional information for adequately defining the extent of damage. The onus is on the radiologist to identify the pattern of injury and to understand the substantial underlying damage that it frequently represents. Conveying this information to the referring clinician is crucial and represents the first step toward additional evaluation and probable orthopedic referral. By recognizing the significance of these injuries at initial presentation, radiologists can facilitate appropriate patient work-up and prevent the chronic morbidity associated with delayed treatment.