Patients Undergoing Manipulation Under Anesthesia Recover Mobility, But Have Worse Functional Outcomes

Area of Science:

• Orthopedics
• Biomedical Engineering
• Rehabilitation Science

Background:

• Regaining range of motion (ROM) after total knee arthroplasty (TKA) is crucial for function.
• Manipulation under anesthesia (MUA) is an option for stiff knees post-TKA, but its effect on gait recovery needs further study.

Purpose of the Study:

• To compare gait quality, function, and ROM in patients who underwent MUA versus those who did not.
• To clarify the gait restoration trajectory following MUA in TKA patients.

Main Methods:

• Secondary analysis of a multicenter observational cohort study using digital care management and smartwatch data.
• Patients with active flexion <90° at 1 month post-TKA were divided into MUA (n=52) and non-MUA (n=218) groups.
• Recovery was assessed using active flexion ROM, Knee Osteoarthritis and Outcomes Scale for Joint Replacement (KOOS JR), and objective gait metrics.

Main Results:

• Gait metrics temporarily decreased post-MUA, with significant differences in walking speed and step count at 5 days.
• Gait metrics normalized between 10-30 days post-MUA.
• ROM was reduced at 1 and 3 months post-MUA, and KOOS JR scores remained significantly lower up to 12 months in the MUA cohort.

Conclusions:

• Gait metrics recover within 5-10 days post-MUA, while patient-reported outcomes (KOOS JR) show a persistent deficit up to one year.
• A disconnect exists between objective gait improvements and subjective patient experiences after MUA.
• Surgeons should be aware of these differing recovery trajectories when counseling TKA patients regarding MUA.