RESUMO
BACKGROUND: This study looks to investigate how not meeting eligibility criteria affects postoperative outcomes following total joint arthroplasty surgery. METHODS: A retrospective review was conducted of total joint arthroplasty patients at a single academic institution. Demographics, laboratory values, and complications were recorded. Continuous and categorical variables were compared using the Student's T-test and the Chi-Square test, respectively. Multivariable analysis was used to control for confounding variables. RESULTS: Our study included 915 total hip and 1,579 total knee arthroplasty patients. For total hip and total knee arthroplasty, there were no significant differences in complications (P = .11 and .87), readmissions (P = .83 and .2), or revision surgeries (P = .3 and 1) when comparing those who met all criteria to those who did not. Total hip arthroplasty patients who did not meet two criteria had 16.1 higher odds (P = .02) of suffering a complication. There were no differences in complications (P = .34 and .41), readmissions (P = 1 and .55), or revision surgeries (P = 1 and .36) between ineligible patients treated by total joint arthroplasty surgeons and those who were not. Multivariable analysis demonstrated no eligibility factors were associated with outcomes for both total hip and knee arthroplasty. CONCLUSIONS: There was no significant difference in outcomes between those who met all eligibility criteria and those who did not. Not meeting two criteria conferred significantly higher odds of suffering a complication for total hip arthroplasty patients. Total joint arthroplasty surgeons had similar outcomes to non-total joint surgeons, although their patient population was more complex. LEVEL OF EVIDENCE: III.
RESUMO
BACKGROUND: Patient activity influences polyethylene wear. However, it is unclear how individual activity changes with patient aging after THA. QUESTIONS/PURPOSES: We quantified changes in individual gait cycles and gait speed, assessed age-related differences in these parameters, and determined their relationship to polyethylene wear. METHODS: A microprocessor was worn on the ankle to quantify the activity of 14 healthy patients with a well-functioning THA at two time periods: early (within 3.5 years of implantation) and late (10-13 postoperative years). Wear was measured on serial radiographs using edge detection-based software. RESULTS: Mean activity decreased by 16% from the early to the late period: 2.04 million gait cycles/year to 1.71 million gait cycles/year. Mean gait speed decreased by 9%: 15.4 cycles/minute to 14.0 cycles/minute. The activity of the 10 patients who were younger than 65 years at surgery decreased by 14% (2.34 million gait cycles/year to 2.02 million gait cycles/year), while the four patients 65 years or older at surgery decreased by 28% (1.29 million gait cycles/year to 0.94 million gait cycles/year). Gait speed was 26% slower for patients 65 years or older than for patients younger than 65 years. The mean linear penetration rate decreased by 42% from the first 5 years (early wear rate) to the next 8 years (late wear rate, 5-13 years): 0.043 mm/year to 0.025 mm/year. CONCLUSIONS: The greatest patient activity and wear occurred during the first 5 years. Walking speed and gait cycles both decreased with aging, resulting in deceasing wear over time.
