Mitochondrial function, grip strength, and activity are related to recovery of mobility after a total knee arthroplasty.

Low muscle quality and a sedentary lifestyle are indicators for a slow recovery after a total knee arthroplasty (TKA). Mitochondrial function is an important part of muscle quality and a key driver of sarcopenia. However, it is not known whether it relates to recovery. In this pilot study, we monitored activity after TKA using a wrist mounted activity tracker and assessed the relation of mitochondrial function on the rate of recovery after TKA. Additionally, we compared the increase in activity as a way to measure recovery to traditional outcome measures. Patients were studied 2 weeks before TKA and up to 6 months after. Activity was monitored continuously. Baseline mitochondrial function (citrate synthase and complex [CP] 1-5 abundance of the electron transport chain) was determined on muscle tissue taken during TKA. Traditional outcome measures (Knee Injury and Osteoarthritis Outcome Score [KOOS], timed up-and-go [TUG] completion time, grip, and quadriceps strength) were performed 2 weeks before, 6 weeks after, and 6 months after TKA. Using a multivariate regression model with various clinical baseline parameters, the following were significantly related to recovery: CP5 abundance, grip strength, and activity (regression weights 0.13, 0.02, and 2.89, respectively). During recovery, activity correlated to the KOOS-activities of daily living (ADL) score (r = 0.55, p = 0.009) and TUG completion time (r = -0.61, p = 0.001). Mitochondrial function seems to be related to recovery, but so are activity and grip strength, all indicators of sarcopenia. Using activity trackers before and after TKA might give the surgeon valuable information on the expected recovery and the opportunity to intervene if recovery is low.

Monitoring the recovery time of children after tonsillectomy using commercial activity trackers.

An observational prospective feasibility study in which children received a tracker 2 weeks before a tonsillectomy and were required to wear it until four weeks postoperatively. The parents used a diary to log the estimated steps of their child. As primary endpoint, the compliance of complete datasets was compared between the tracker and the diary. As secondary endpoints, the agreement of steps between tracker and diary, and the recovery time after tonsillectomy were analyzed.Twenty-four patients (50% male) with a median age of 6 years were recruited. The tracker had a complete dataset compliance of 91.7% in the pre-operative and 58.3% in postoperative period, whereas the diary's compliance was 62.5% in the pre-operative and 12.5% in the postoperative period. The difference of 29.2% and 45.8% in the pre-operative and postoperative periods between the tracker and the diary was significant (p < 0.005). The tracker and diary had a mean agreement difference of 1063 steps per day. Mean recovery time was 21 days after tonsillectomy.Conclusion: The results of this pilot study support the use of a tracker in terms of compliance and practicability. Consumer-level activity trackers are a viable alternative to conventional manual logging for clinical use in pediatric research.Trial registration: ClinicalTrials.gov Identifier: NCT03174496 What is known: • Consumer-level activity trackers are already used in clinical research to monitor steps and physical activity. • The use of consumer-level activity trackers in clinical studies has mostly been validated in the adult population. What is new: • This study proves the feasibility of using physical activity trackers in a pediatric population before and after a surgical intervention. • Recovery of a patient could be assessed with an activity tracker.