Randomized controlled trial of compressive cryotherapy versus standard cryotherapy after total knee arthroplasty: pain, swelling, range of motion and functional recovery.

Background: After total knee arthroplasty (TKA), patients have limited knee range of motion (ROM), trophic changes and pain. Cryotherapy and compression are recommended in the literature, but no study has shown that cryotherapy and compression combined leads to better results than cryotherapy alone. The primary objective was to compare knee ROM after 21 days of rehabilitation post-TKA between patients who underwent rehabilitation with compressive cryotherapy with those who had cryotherapy alone. The secondary objectives were to compare other trophic, pain and functional outcomes.

Methods: Forty patients were randomized into two groups: Standard Cryotherapy (SC = 20, median age 77 years), which applied cold packs along with their rehabilitation; and Compressive Cryotherapy (CC = 20, median age 76 years), which received cold compression. Knee joint's passive and active ROM (primary outcome) were measured with a goniometer. Knee's circumference, fluctuation test, pain at rest and during activity, 6-minute walking test (6MWT) and KOOS questionnaire were secondary outcomes. The groups were compared on D1 (baseline) and D21 of rehabilitation. A survival analysis has compared the groups on D1, D8, D15, D21.

Results: All subjects had a significant improvement in all the parameters on D21 relative to D1 (p < .05), except for pain at rest (p = .065 for CC and p = .052 for SC). On D21, the CC group had a significantly larger improvement in the joint effusion (p = .002), pain during activity (p = .005), 6MWT (p = .018) and KOOS (p = .004) than the SC group. Based on the survival analysis, the CC group had significantly faster improvement in the joint ROM (p = .011 for flexion and p = .038 for extension) and knee circumference (p = .013) than the SC group.

Conclusions: Both cryotherapy methods improved joint ROM, trophic changes, pain and function. Adding dynamic compression to a cryotherapy protocol provided further benefits: a significantly faster improvement in passive knee flexion ROM, a greater reduction of swelling, and pain during activity. Similarly, walking distance and KOOS questionnaire were significantly better for CC.

Trials Registration: The study was registered in the ClinicalTrials.gov database on 14/09/2023 (identifier: NCT06037824).