Multifactorial assessments are required to evaluate balance and locomotor function in people with lower-limb amputations. There is no consensus about whether a single screening tool could be used to identify future issues with locomotion or prosthetic use. To this extent, a team of physical therapists conducted a retrospective cohort study to examine the correlation of locomotor performance during rehabilitation of patients with lower-limb amputation and prosthetic abandonment 12 months after discharge. Their objective was to determine if different tests of locomotor performance during rehabilitation were associated with significantly greater risk of prosthetic abandonment at 12 months post-discharge.
For the study, descriptive variables, ten-meter walk tests (10MWT), Timed Up and Go (TUG) tests, six-minute walk tests (6MWT), and Four Square Step Tests (FSST) were abstracted from the medical records for 201 consecutive participants with lower-limb amputations. Participants were interviewed and classified as prosthetic users or non-users at 12 months post-discharge. The Mann-Whitney U test was used to analyze if there were differences in locomotor performance. Receiver operator characteristic curves were generated to determine performance thresholds and relative risk (RR) was calculated for non-use.
At 12 months post-discharge 18 percent (36) of the cohort had become prosthetic non-users. Performance thresholds, area under the curve (AUC), and RR of non-use (95 percent confidence intervals (CI)) were recorded, as follows:
- 10MWT: If walking speed was ≤ 0.44 ms-1 (AUC = 0.743), RR of non-use = 2.76 (CI 1.83-3.79)
- TUG test: If time was ≥ 21.4s (AUC = 0.796), RR of non-use = 3.17 (CI 2.17-4.14)
- 6MWT: If distance was ≤ 191m (AUC = 0.788), RR of non-use = 2.84 (CI 2.05-3.48)
- FSST: If time was ≥ 36.6s (AUC = 0.762), RR of non-use = 2.76 (CI 1.99-3.39)
The study concludes that locomotor performance during rehabilitation may predict future risk of prosthetic non-use. It may be implied that the 10MWT has the greatest clinical utility as a single screening tool for prosthetic non-use given that the highest proportion of participants were able to perform this test early in rehabilitation. However, as locomotor skills improve, other tests, in particular the 6MWT, have specific clinical utility. To fully enable implementation of these locomotor criteria for prosthetic non-use into clinical practice, validation is warranted.
The study, “Locomotor Performance During Rehabilitation of People With Lower Limb Amputation and Prosthetic Nonuse 12 Months After Discharge,” was published December 4, online before print, in the journal Physical Therapy.
