Mobile Site ›

Evaluation of Prosthetic Implant Degradation

Orthopedic Prostheses



Subscribe

Receive notification when new Hot Topics are published:

Patient Workup

Slide 4

December 2011

Patients experiencing joint pain after a metal-on-metal hip replacement should be evaluated appropriately. The majority of failures associated with metal-on-metal implants are not necessarily due to the bearing surface itself, and therefore an evaluation should be carried out to rule out implant loosening and infection. Pain is a characteristic symptom. Patients can experience groin or buttock pain, and in select patients with pseudotumors, a fluid-filled collection can be present around the lateral aspect of the hip. Flexion around the hip from activities such as going up stairs or sliding into a car are particularly painful and may point towards iliopsoas irritation or impingement, which is commonly seen with these implants. Patients with pain should undergo evaluation with an anteroposterior pelvis and a lateral radiograph and should get screening blood work including a complete blood cell count with differential, sedimentation rate, and C-reactive protein level as a baseline to rule out infection. If these tests are elevated, the hip should be aspirated. Once infection is ruled out and adverse reaction to metal debris is suspected, then cobalt and chromium serum concentrations and an ultrasound or MRI of the hip with metal suppression is performed to rule out the presence of pseudotumor. The term most accepted today for this phenomenon around metal-on-metal hip arthroplasty is ARMD or adverse reaction to metal debris.

Patient Workup

 


Jump to section:


Key