BACKGROUND: The relationship between intra-articular injections and complication rates after total knee arthroplasty (TKA) remains controversial. This study's purpose was to determine the relationship between the number and timing of intra-articular injections with complications and outcomes after TKA from a single surgeon's database. METHODS: We retrospectively reviewed a series of 442 patients who underwent primary TKA from 2008-2015. Patient demographics, comorbidities, number and timing of ipsilateral intra-articular injections, and preoperative and postoperative functional outcome scores were recorded. Complications and infection rates at a minimum of 12-month follow-up were compared between patients who received 3 or less preoperative injections and those who received 4 or greater before TKA. Multivariate logistic regression analysis was performed to identify independent risk factors for complications and poor short-term outcomes after TKA. RESULTS: Of the 442 patients enrolled in the study, 390 patients (90%) received an ipsilateral injection before TKA. Patients receiving 4 or more injections (175 patients, 40%) did not have a difference in complication rate (14% vs 17%, P = .346), poor functional outcomes (6% vs 9%, P = .299), or infection rate (2% vs 4%, P = .286). When controlling for confounding variables, intra-articular corticosteroid, viscosupplementation, and any injection within 90 days were not associated with an increase in complications, infection, or poor functional outcomes after TKA (all P > .05). CONCLUSION: Our data suggest that there is no relationship between timing and number of intra-articular injections with complication rate, infection, or poor short-term functional outcomes. Further larger studies are needed to confirm these findings.
BACKGROUND: The relationship between intra-articular injections and complication rates after total knee arthroplasty (TKA) remains controversial. This study's purpose was to determine the relationship between the number and timing of intra-articular injections with complications and outcomes after TKA from a single surgeon's database. METHODS: We retrospectively reviewed a series of 442 patients who underwent primary TKA from 2008-2015. Patient demographics, comorbidities, number and timing of ipsilateral intra-articular injections, and preoperative and postoperative functional outcome scores were recorded. Complications and infection rates at a minimum of 12-month follow-up were compared between patients who received 3 or less preoperative injections and those who received 4 or greater before TKA. Multivariate logistic regression analysis was performed to identify independent risk factors for complications and poor short-term outcomes after TKA. RESULTS: Of the 442 patients enrolled in the study, 390 patients (90%) received an ipsilateral injection before TKA. Patients receiving 4 or more injections (175 patients, 40%) did not have a difference in complication rate (14% vs 17%, P = .346), poor functional outcomes (6% vs 9%, P = .299), or infection rate (2% vs 4%, P = .286). When controlling for confounding variables, intra-articular corticosteroid, viscosupplementation, and any injection within 90 days were not associated with an increase in complications, infection, or poor functional outcomes after TKA (all P > .05). CONCLUSION: Our data suggest that there is no relationship between timing and number of intra-articular injections with complication rate, infection, or poor short-term functional outcomes. Further larger studies are needed to confirm these findings.