Dynamic view of postoperative pain and quality of life evolution after total knee arthroplasty - a prospective observational study.

BACKGROUND: Having a dynamic view of postoperative pain resolution allows a better understanding of the transition towards chronic pain. Sleep and quality of life are important determinants of satisfaction after TKA, besides functional recovery and pain. METHODS: For 114 patients undergoing TKA we recorded the presence of pain at rest, pain evoked at movement and pain located at the incision site in the acute (postoperative day 1, 2, 3, 8), subacute (30 days, 3 months) and chronic (6 months and 1 year) period. Analgesics consumption and need of medical assistance for pain were questioned. Quality of life measured by the impact on enjoyment of life, sleep and mood were monitored. RESULTS: Average incidence for subacute pain was 54% at rest, 66% at mobilization. For chronic pain, the incidence was 14% at rest, 22% during mobilization. Pain at rest peaked at day 30 while pain during mobilization displayed a plateau between day 8 and 3 months. Three per cent of the patients complained at 1 year of pain at the incision site. 11% of patients still took analgesics one year after the surgery. More than 40% of patients reported moderate to severe alterations of sleep and quality of life in the acute period, decreasing to less than a half at one year. CONCLUSION: The trajectories of the different types of pain after TKA show their nonlinear evolution, highlighting the need of a better pain control at precise moments. Sleep disturbances and alterations of quality of life are still present one year after the surgery