METHODS: Twenty-three participants wore a Fitbit Charge or Apple Watch Series 4 smart watch and performed a walking test along a 50-metre hallway. There were 9 males and 14 females included in the study with an average age of 68.5 years and BMI of 32. Each patient wore both the Fitbit Charge and Apple Watch while completing the walking test and an observer counted the ground truth value using a thumb-push tally counter. This test was repeated pre-operatively with no gait aid, immediately post operatively with a walker, at 6 weeks follow up with a cane and at 6 months with no gait aid. Bland-Altman plots were performed for all walking tests to compare the agreement between measurement techniques.
RESULTS: Mean overall agreement of step count for pre-operative and at 6 months for subjects walking without gait aids was excellent for both the Apple Watch vs. actual and Fitbit vs. actual with bias values ranging from - 0.87 to 1.36 with limits of agreement (LOA) ranging between - 10.82 and 15.91. While using a walker both devices showed extremely little agreement with the actual step count with bias values between 22.5 and 24.37 with LOA between 11.7 and 33.3. At 6 weeks post-op while using a cane, both the Apple Watch and Fitbit devices had a range of bias values between - 2.8 and 5.73 with LOA between - 13.51 and 24.97.
CONCLUSIONS: These devices show poor validity in the early post operative setting, especially with the use of gait aids, and therefore results should be interpreted with caution.
方法:23名参与者佩戴FitbitCharge或AppleWatchSeries4智能手表,并在50米长的走廊上进行步行测试。该研究包括9名男性和14名女性,平均年龄为68.5岁,BMI为32。每位患者在完成步行测试时都戴着FitbitCharge和AppleWatch,观察者使用拇指推式计数计数器计算地面真值。术前重复这项测试,没有步态辅助,手术后立即用助行器,在6周时用手杖随访,在6个月时没有步态援助。对所有步行测试进行了Bland-Altman地块,以比较测量技术之间的一致性。
结果:对于没有步态辅助的受试者,术前和6个月时步数的平均总体一致性对于AppleWatch和实际和Fitbitvs.实际偏差值范围为-0.87至1.36,协议界限(LOA)范围为-10.82至15.91。在使用助行器时,两种设备均显示出与实际步数的极小一致性,偏差值在22.5和24.37之间,LOA在11.7和33.3之间。术后6周使用拐杖时,AppleWatch和Fitbit设备的偏差值范围在-2.8和5.73之间,LOA在-13.51和24.97之间。
结论:这些器械在术后早期设置中的有效性较差,尤其是使用步态辅助设备,因此,应谨慎解释结果。