There is a gold standard for the identification and diagnosis of a failed or loosened knee replacement.

The hardware can fail due to unknown factors in some cases. In other words, when a failure occurs with a total knee replacement, it’s not necessarily surgeon error at play.

And when the hardware begins loosening up, the patient starts to experience pain in the knee. The pain could be pretty bad, too.

Gold Standard for Diagnosing a Failed Knee Replacement

“The gold standard is serial X-rays and follow-up exam,” says Henry Boucher, MD, clinical instructor of Adult Reconstruction, Medstar Union Memorial Orthopaedics, Baltimore, MD.

He continues, “These diagnose the vast majority of loose implants.”

What about a Marcaine injection to diagnose a failed knee replacement surgery?

Marcaine is an anesthetic, and an orthopedic surgeon may inject the bothersome joint for an evaluation.

“The injection is best to determine if the knee is the actual cause of pain,” says Dr. Boucher.

Pain in the joint may actually originate from elsewhere in the body. The Marcaine injection can rule out referred pain from another location, “but it does not give the exact diagnosis,” says Dr. Boucher.

An arthogram can look for any loosening or instability in the knee joint.

A bone scan may also be used to look for tell-tale signs of a failed knee replacement, but Dr. Boucher adds that a bone scan is not always reliable, and is open to conflicting interpretation by doctors.

While one surgeon sees no problem with the hardware as viewed on the bone scan image…another surgeon may identify a loosening.

Causes of Loosened Knee Replacements

• Friction caused by the joint surfaces wearing away the implant surface.

• Bacterial infection on the metal or plastic pieces.

• The soft tissue that surrounds the knee is not strong enough to support walking or even standing.

• The implants have been incorrectly placed.

Dr. Boucher’s specialties are hip and knee surgery, replacement and revision, and sports medicine surgery. He has been the recipient of the Golden Apple Award for teaching excellence multiple times.
Lorra Garrick has been covering medical, fitness and cybersecurity topics for many years, having written thousands of articles for print magazines and websites, including as a ghostwriter. She’s also a former ACE-certified personal trainer.  



Top image credit: Rama