JOA - 2026-04-22 - Journal Article
Preoperative Malnutrition is Associated with Increased Risk of Periprosthetic Joint Infection and Reduced Revision-Free Survival Following Unicompartmental Knee Arthroplasty.
Ilyas MH, Kang H, Freeman I, Sampson WT, Mannina C, Kwon YM
Topics
Key Takeaway
Preoperative malnutrition (albumin ≤3.5 g/dL, transferrin ≤204 mg/dL, or TLC ≤1.5×10³/µL) triples the 2-year PJI rate after UKA (2.4% vs. 0.8%, RR 3.00) and reduces revision-free survival to 93.34% vs. 95.14%.
Summary Depth
Choose how much analysis to show on this article page.
Summary
This propensity-matched retrospective cohort study used a collaborative network database to determine whether preoperative laboratory-defined malnutrition affects 90-day medical and 2-year implant-related outcomes after UKA. Malnourished patients had a 3.36-fold increased risk of wound complications and 3.36-fold increased risk of AKI at 90 days. At 2 years, PJI risk was tripled (RR 3.00), revision risk was elevated (RR 1.38), and Kaplan-Meier revision-free survival was 93.34% vs. 95.14%.
Key Limitation
Database-derived outcomes rely on coding accuracy and cannot confirm whether malnutrition was addressed preoperatively, precluding any assessment of whether nutritional optimization actually mitigates the identified risks.
Original Abstract
BACKGROUND
Malnutrition is a recognized risk factor for adverse outcomes following total joint arthroplasty, yet its influence on unicompartmental knee arthroplasty (UKA) remains poorly defined. This study aimed to evaluate the potential association between preoperative laboratory markers of malnutrition and the risk of 90-day postoperative medical complications, as well as implant-related complications in patients undergoing UKA.
METHODS
A retrospective cohort study was conducted using a collaborative network database. Malnutrition was defined by at least one preoperative laboratory value of serum albumin less than or equal to 3.5 g/dL, transferrin less than or equal to 204 mg/dL, or total leukocyte count less than or equal to 1.5 × 10 3 /μL. Propensity score matching (one-to-one) was performed using demographic and clinical variables, yielding two matched cohorts of 1,719 patients. Both 90-day and two-year complications, including periprosthetic joint infection (PJI), mechanical complications, and revision rates, were compared. Risk estimates with 95% confidence intervals were generated using the database's analytical platform.
RESULTS
At 90 days, malnourished patients demonstrated increased risks of emergency department visitation (10.7 versus 6.0%; RR [risk ratio] 1.77, P < 0.001), wound complications (3.6 versus 1.1%; RR 3.36, P < 0.001), venous thromboembolism (3.2 versus 1.4%; RR 2.36, P = 0.005), and acute kidney injury (4.6 versus 1.4%; RR 3.36, P < 0.001). At two years, malnutrition remained independently associated with higher rates of PJI (2.4 versus 0.8%; RR 3.00, P < 0.001), revision surgery (6.3 versus 4.6%; RR 1.38, P = 0.025), and mechanical complications (2.8 versus 1.6%; RR 1.82, P = 0.010). Kaplan-Meier analysis similarly showed reduced revision-free survival in malnourished patients, with a two-year survival of 93.34% compared with 95.14% in controls.
CONCLUSION
In this study, preoperative malnutrition was associated with significantly increased 90-day medical complications, higher two-year rates of PJI, mechanical complications, and revision surgery, as well as reduced revision-free survival in UKA patients. These findings highlight nutritional status as a clinically relevant and potentially modifiable risk factor and support routine preoperative nutritional screening in patients undergoing UKA.