Measurement of the knee flexion angle with smartphone applications: Which technology is better?

Purpose: The range of motion of the knee is a critical element of clinical assessment. The tested hypothesis was that the measurement of the knee flexion angle measured with two specific smartphone applications using either inclinometer or camera technology was different from the reference measurement with a navigation system designed for total knee arthroplasty (TKA).

Methods: Ten consecutive patients were selected for navigation-assisted TKA.

Routine one-stage exchange for chronic infection after total hip replacement.

Purpose: We hypothesized that a routine one-stage exchange for treatment of chronically infected total hip replacement (THR) will lead to (1) a higher rate of infection recurrence and (2) a poorer hip outcome than the published rates after two-stage exchange.

Methods: Sixty-five cases have been treated consecutively with one-stage exchange. All patients have been followed for a period of three to six years or until death or infection recurrence.

High Activity Arthroplasty Score has a lower ceiling effect than standard scores after knee arthroplasty.

The tested hypothesis was following: the High Activity Arthroplasty Score has a significant lower ceiling effect than American Knee Society Score and Oxford Knee Score after total knee arthroplasty. One hundred patients operated on for total knee arthroplasty with more than one-year follow-up have been included. The ceiling effect was 53% for the American Knee Society Score, 33% for the Oxford Knee Score, and 0% for the High Activity Arthroplasty Score.

Navigated revision TKR: a comparative study with conventional instruments.

We selected 86 cases for the study: 50 navigated revision total knee replacements (TKRs) and 36 conventional revision TKRs. We hypothesized that the rate of satisfactory implantation would be higher for navigated revision TKR than for conventional revision TKR. The primary criterion was the rate of optimally implanted prostheses on postoperative anteroposterior and lateral long leg radiographs.