The prevalence of bilateral and ipsilateral radiographic osteoarthritis is high in White, Asian and Native Hawaiian/Pacific Islanders presenting for unilateral knee or hip arthroplasty.

BACKGROUND: It is estimated that one-third of patients presenting with unilateral joint pain have contralateral osteoarthritis (OA) at first presentation. Most studies have primarily examined White patient cohorts. The purpose of this study was to determine the prevalence of contralateral joint OA for patients presenting for unilateral total knee (TKA), unicompartmental knee (UKA) or total hip arthroplasty (THA) among Asian, Native Hawaiian/Pacific Islander and White patients. METHODS: Bilateral radiographic reports at initial presentation of 2,312 subjects who underwent unilateral arthroplasties (332 UKAs, 933 TKAs and 1,047 THAs) were reviewed. The presence of contralateral OA was recorded and compared by racial group and type of arthroplasty performed. Parametric statistical analyses were performed to determine differences between groups. Multivariable analyses were completed for each arthroplasty group to determine the influence on the presence of contralateral OA, presented as odds ratios and 95% confidence intervals. RESULTS: Contralateral joint OA was present in 86.7%, 90.4% and 70.4% of UKA, TKA and THA patients, respectively. Concurrent hip OA was present in 41.6% and 59.5% of UKA and TKA patients. No racial differences in the prevalence of contralateral knee OA were found for knee arthroplasty patients. White patients (74.6%) had a greater prevalence of contralateral hip OA compared to Asians (66.5%, p = 0.037) amongst THA recipients. Increased age and body mass index were significantly associated with the presence of contralateral knee OA. Increased age, being male and being White were significant contributors for the presence of contralateral hip OA. CONCLUSION: The prevalence of contralateral joint OA and concurrent hip OA is high in all three racial groups. Due to the extensive prevalence of contralateral and concurrent knee and hip OA, bilateral radiographic evaluation should be considered for all patients presenting with unilateral hip or knee pain due to OA.

Complications following single-stage bilateral total knee arthroplasty and unilateral procedures: experience of a high-volume community hospital.

INTRODUCTION: The safety of single-stage bilateral total knee arthroplasty (SSBTKA) compared to unilateral total knee arthroplasty (TKA) remains controversial. The present study compares the 90-day postoperative complications encountered following SSBTKA and unilateral TKA in an unselected cohort of patients performed at a high-volume community hospital. MATERIALS AND METHODS: The perioperative electronic medical records of an unselected consecutive cohort of 1032 patients (1345 knees) having undergone unilateral or SSBTKA were reviewed. Ninety-day postoperative complications or need for additional procedures were compared between unilateral and SSBTKA groups. RESULTS: A total of 719 and 313 patients underwent unilateral and SSBTKA, respectively. There were no significant differences in age or BMI between groups. Patients undergoing SSBTKA were more likely to be male (p = 0.019), have longer lengths of stay (p < 0.001) and were less likely to discharge directly home (13.1%) compared to unilateral patients (80.9%) (p < 0.001). Patients undergoing SSBTKA were more likely to require a transfusion (14.7%) compared to unilateral patients (2.2%) (p < 0.001). Interestingly, mortality rate following unilateral TKA (1.7%) was significantly higher than SSBTKA (0.0%) (p = 0.013). There were no significant differences regarding other complications or need for additional procedures within 90 days following surgery. CONCLUSION: SSBTKA did not result in greater complications when compared to unilateral TKA in this particular cohort. As expected, transfusion rates will likely be higher and there will be a greater need for acute inpatient care following surgery for SSBTKA patients.

Favorable outcomes of posterior cruciate-stabilized inserts over ultracongruent inserts in total knee arthroplasty.

OBJECTIVE: Posterior cruciate-stabilized (PS) and ultracongruent (UC) inserts are used during total knee arthroplasty (TKA), but superiority in gaining postoperative knee flexion and functionality remains contested. Therefore, this study compared postoperative outcomes between PS and UC inserts. METHODS: A retrospective review evaluated unilateral or bilateral TKAs with PS or UC inserts from August 2011 to March 2020. Nonparametric statistics were performed to evaluate differences in patient demographics, pre- and postknee flexion and Knee Society Knee (KSS-K) and Function Score (KSS-F). Univariate and multivariable regressions were performed to evaluate the influence on postoperative knee flexion ≥ 120°, presented as odds ratios (OR) and 95% confidence intervals (CI). RESULTS: Patient demographics were not significantly different between the 577 PS and 399 UC knees evaluated. Postoperatively, a larger proportion of UC knees demonstrated knee flexion < 120° (36.0% vs. 18.6%, p < 0.001) and lower KSS-K (91.0 ± 8.7 vs. 91.6 ± 10.3, p < 0.001) and KSS-F (76.8 ± 21.6 vs. 79.9 ± 21.6, p = 0.007) than the PS group. The PS group had greater improvement in flexion angle (4.9° ± 14.9° vs. 1.0° ± 15.6°, p < 0.001) and KSS-F (27.3 ± 23.3 vs. 23.1 ± 25.3, p = 0.007) as compared to that of UC patients. Patients with preoperative flexion < 120° (OR 2.787, CI 2.066-3.761; p < 0.001), higher body mass index (OR 1.033, CI 1.006-1.061; p = 0.017) and UC insert (OR 2.461, CI 1.832-3.307; p < 0.001) were less likely to achieve flexion ≥ 120°. CONCLUSION: Favorable clinical and functional outcomes were noted in the PS group as compared to UC inserts in TKA. The greater improvement in overall knee flexion may suggest the PS insert may be especially appropriate for patients with lower preoperative range of motion. LEVEL OF EVIDENCE: III, retrospective comparative study.

Do older patients fare worse following unilateral or single stage bilateral total knee arthroplasty?

INTRODUCTION: The safety and benefits of single stage bilateral total knee arthroplasty (SSBTKA) among older patients as compared to unilateral TKA remains controversial. This study aimed to evaluate the influence of age and comorbidities on complications and early outcomes for unilateral and BTKA in patients over and under 70 years of age. MATERIALS AND METHODS: This prospective study compared postoperative complications and early patient-reported outcomes at 6 weeks of 142 unilateral TKA patients (N = 75, ≤ 70; N = 67, > 70) and 89 SSBTKA patients (N = 48, ≤ 70; N = 41, > 70). Patients completed the KOOS JR and PROMIS Global Mental (GMH) and Global Physical Health (GPH) surveys. Knee Society Scores for Knee (KSS-K) and Function (KSS-F) were completed in the clinic. Parametric tests were performed for comparisons of unilateral and BTKA outcomes and complications for patients over and under 70. RESULTS: While patient demographics were similar, patients > 70 had more comorbidities than patients ≤ 70 (p < 0.004). There were no significant differences in postoperative complications or readmissions between age groups or procedures. Unilateral TKA patients > 70 had significantly lower pre- (p < 0.001) and post-operative (p = 0.011) KSS-F scores compared to those ≤ 70. SSBTKA patients > 70 had significantly higher preoperative GMH (p = 0.029), postoperative KSS-K (p = 0.027), KOOS JR scores (p = 0.039) and satisfaction (p = 0.048) compared to those ≤ 70. CONCLUSION: Age did not influence the risk of early postoperative complications. Additionally, the greater improvements in KOOS JR and higher patient satisfaction for SSBTKA patients > 70 suggests that SSBTKA may meet elderly patient expectations and should not necessarily be discouraged due to safety concerns.

Fixed 6° distal femoral cut consistently achieves neutral alignment for Asians, Caucasians, and Native Hawaiian/Pacific Islanders.

BACKGROUND: Restoration of a neutral mechanical axis (MA) is important to the success of total knee arthroplasty (TKA). While known differences are present between Asians and Caucasians regarding native knee alignment, it is unknown whether such differences exist amongst Native Hawaiian/Other Pacific Islanders (NHPI) or if utilizing a fixed distal femoral cut of 6° can consistently achieve a neutral MA in these minority racial groups. This study examines the preoperative deformities presented by Asians, Caucasians, and NHPI, and the resulting knee alignment achieved following TKA when a fixed 6° distal femoral cut is targeted for all patients. METHODS: Preoperative and postoperative MA was measured from 835 Asian, 447 Caucasian, and 163 NHPI hip-to-ankle radiographs. All patients underwent TKA in which a standard distal femoral cut of 6° valgus was targeted for all patients. Data were evaluated as continuous variables and by groupings of varus (MA < - 3°), valgus (MA > 3°), and neutral (- 3° ≤ MA ≤ 3°) alignment. RESULTS: Preoperative deformity ranged from 38° varus to 29° valgus. The proportion of Asian and NHPI presenting with varus alignment prior to surgery was significantly greater than Caucasian patients in both males (Asians: 80.6%; Caucasians: 67.0%; NHPI: 79.0%, p = 0.001) and females (Asians: 66.1%; Caucasians: 45.7%; NHPI: 63.2%, p < 0.001). There was no difference in the proportion of patients (72-79%) achieving a neutral MA amongst all three racial groups. CONCLUSION: NHPI appear to have similar preoperative deformities to Asians with both groups having significantly more varus alignment than Caucasians. Despite a wide range of preoperative deformity, application of a fixed distal femoral cut of 6° valgus successfully established a neutral MA equally in the majority of patients across all three racial groups.