Does ethnicity and education influence preoperative disability and expectations in patients undergoing total knee arthroplasty?

AIM To investigate whether minority ethnicity and the duration of education influence preoperative disability and expectations in patients undergoing total knee arthroplasty.METHODS We prospectively included 829 patients undergoing primary unilateral total knee arthroplasty(TKA) from April 2013 to December 2014 at a single centre. Patients filled in pre-operative questionnaires with information regarding place of birth, duration of education, expectations for outcome of surgery and baseline characteristics. Patients were stratified based on ethnicity. Majority ethnicity was defined as born inthe study country and minority ethnicity was defined as born in any other country. Similarly, patients were stratified based on duration of education in groups defined as < 9 years, 9-12 years and > 12 years, respectively.RESULTS We found that 92.2% of patients were of majority ethnicity. We found that 24.5%, 44.8% and 30.8% of patients had an education of < 9 years, 9-12 years and > 12 years, respectively. The mean preoperative(preOP) oxford knee score(OKS) in the total population was 23.6. Patients of minority ethnicity had lower mean pre-OP OKS(18.6 vs 23.9, P < 0.001), higher pain levels(VAS 73.0 vs 58.7, P < 0.001), expected higher levels of post-OP pain(VAS 14.1 vs 6.1, P = 0.02) and of overall symptoms(VAS 16.6 vs 6.4, P = 0.006). Patients with > 12 years education had lower mean pre-OP OKS(21.5 vs 23.8 and 24.6, P < 0.001) and higher pre-OP VAS pain(65.4 vs 59.2 and 56.4, P < 0.001) compared to groups with shorter education. One year post-operative(post-OP) patients of minority ethnicity had lower mean OKS, higher pain and lower QoL. One year post-OP patients with > 12 years education reported higher pain compared to patients with shorter educations. However, the response-rate was low(44.6%), and therefore post-OP results were not considered to be significant.CONCLUSION Minority ethnicity and the duration of education influ-ence preoperative disability and expectation in patients undergoing TKA. This should be taken into account when patients are advised pre-operatively.

Early clinical outcome and learning curve following unilateral primary total knee arthroplasty after introduction of a novel total knee arthroplasty system

BACKGROUND New implants for total knee arthroplasty(TKA)are continuously introduced with the proposed benefit of increased performance and improved outcome.Little information exists on how the introduction of a novel arthroplasty implant affects the perioperative and surgical outcome immediately after implementation.AIM To investigate how surgery-related factors and implant positioning were affected by the introduction of a novel TKA system.METHODS A novel TKA system was introduced at our institution on 30th November 2015.Seventy-five TKAs performed with the Persona TKA immediately following its introduction by 3 different surgeons(25 TKAs/surgeon)were identified as the Introduction Group.Moreover,the latest 25 TKAs performed by each surgeon prior to introduction of the Persona TKA were identified as the Control Group.A Follow-up Group of 25 TKAs/surgeon was identified starting 1-year after the end of the introduction period.Demographics,surgery-related factors and alignment data were recorded,and intergroup differences compared.RESULTS Following introduction of the novel implant,Persona TKA was utilized in 69%(71%),53%(54%),and 45%(75%)of primary TKA procedures by the three surgeons,respectively(Follow-up Group).Mean surgery time was increased by 28%(P<0.0001)and mean intra-operative blood loss by 25%(P=0.002)in the Introduction Group,while only the mean surgery time was increased in the Follow-up Group by 18%(P<0.0001).Overall alignment was similar between the groups apart from femoral flexion(FF)and tibial slope(TS).The number of FF outliers was reduced in the Introduction Group with a more pronounced decrease in the Follow-up Group.CONCLUSION Introduction of the new TKA implant increased surgical time and intraoperative blood loss immediately after its introduction.These differences diminished one year after introduction of the new implant.Fewer outliers with respect to FF and TS were seen when using the novel TKA implant.Further studies are needed to investigate if these differences persist over time and correlate with patient reported outcomes.