[Is it possible to propose the abolition of crutches according to the gait speed in patients with total knee arthroplasty?].

OBJECTIVE

To determine the stop of crutches to walk in patients with total knee arthroplasty from the test of maximal gait speed.

METHOD: 46 patients (73.6 +/- 4.6 years) carried out the maximal gait speed test on a 10-meter track, with two crutches, at the 3rd week after a total knee arthroplasty surgery for gonarthrosis. Two groups were separated according to the need of crutches to walk. Various threshold values of maximal gait speed were then determined (ROC curve) to know if this parameter could define the stop of crutches to walk (Predictive value).

RESULTS

Patients able to stop crutches (n = 27) walk faster, than the patients who still need crutches (n = 19), (0.86 +/- 0.17 m/s vs 0.65 +/- 0.14 m/s; p < 0.01). According to the ROC curve, two speeds were chosen: 1.11 m/s (9 s) and 0.55 m/s (18 s). A gait speed superior or equal to 1.11 m/s presents a positive predictive value of 86% to authorize to stop crutches. Below 0.55 m/s, the positive predictive value is 83% to keep crutches. Between these two speeds, the test of maximal gait speed does not help the clinician to decide to stop crutches.

CONCLUSION

The test of maximal gait speed brings a help to decide to stop crutches only for speeds superior to 1.11 m/s.