Stop Revising Painful Knees Without This Simple Pre-Op Prognostic Tool

Unpacking the data that shows patient satisfaction drops to 47% in revision patients who report less than 50% pain relief during their preoperative injection.

The efficacy and success of total knee arthroplasty (TKA) in treating patients with end-stage osteoarthritis are well established. However, revision rates range from 3 to 10% at 10-year follow-up. Reasons for failure include more obvious diagnoses, such as periprosthetic fracture and periprosthetic joint infection. With some exceptions, these complications can be diagnosed and treated expediently. However, other reasons for failure, such as instability and aseptic loosening, can prove more difficult to diagnose with a standard painful TKA workup algorithm.

Flexion instability has emerged as one of the most common causes of TKA failure in recent years. However, the diagnosis can be challenging as it remains difficult to predict patients who can tolerate laxity vs those who cannot. Without obvious radiographic changes over time, subtle aseptic loosening and, in particular, cemented implants, debonding, and failure of cementless ingrowth can also be difficult to accurately diagnose radiographically, and supplemental bone scans are known to have high false-positive and false-negative rates. Revision TKA without a clear diagnosis is not recommended due to poor results.