To investigate the effect of enhanced recovery after surgery (ERAS) in primary unilateral total knee arthroplasty (TKA).

From January 2016 to January 2018, 88 patients who underwent primary unilateral TKA from the orthopedic department of affiliated Jianhu Hospital of Nantong University were divided into two groups by random number method: ERAS group(experimental group, n=44)and routine group (control group, n=44). Inclusion criteria: the patients meet the diagnostic criteria for knee arthritis, and undergoing total knee replacement for the first time. Those who did not meet the diagnosis and inclusion criteria were excluded. Follow-up assessment included postoperative hemoglobin at 24 h after operation, blood transfusion ratio, length of stay (LOS), postoperative complications, visual analogue scale(VAS), the Hospital for Special Surgery (HSS) score and knee range of motion (ROM) at 24 h, one month, six months and 12 months after the operation. Group design data t test was used to compare LOS and hemoglobin between the two groups. Paired design data t test was used to compare hemoglobin before and after operation in the two groups. Analysis of variance of repeated measurement data was used to compare VAS score, HSS score and ROM of knee joint. Chi-square test or Fisher exact probability method was used for counting data.

The postoperative hemoglobin after 24 h in the experimental group was significantly higher than that in the control group. The blood transfusion ratio and the incidence of complications in the experimental group were significantly lower than those in the control group. The LOS in the experimental group was significantly shorter than that in the control group. The total difference of VAS score, HSS score, knee ROM between the two groups were statistically significant(VAS score F=9.87, HSS score F=10.98, ROM F=9.94, all P<0.001) which showed that the experimental group were better than the control group. In terms of grouping, the difference of VAS score between the experimental group and the control group was statistically significant at 24 h, and one month postoperatively(t=7.1392, 3.9855, both P<0.05). The difference of HSS score and ROM of knee joint between the experimental group and the control group was statistically significant at 24h, one month, and six months postoperatively(HSS score t=6.6350, 5.7948, 3.5763, all P<0.05; ROM t=7.8032, 3.9390, 4.7654, all P<0.05). The difference of VAS score between the experimental group and the control group was not statistically significant at six and 12 months postoperatively(t=0.5688, 0.5180, both P>0.05). The HSS score and ROM of knee joint between the experimental group and the control group was not statistically significant at 12 months postoperatively(HSS t=0.7687, ROM t=0.9523, both P>0.05). In terms of time, the VAS score of the experimental group and the control group decreased from pre-operation to 12 months after operation, and the HSS score and ROM of the knee joint of the experimental group and the control group increased from pre-operation to 12 months after operation.

The application of ERAS in primary unilateral TKA can reduce blood loss and the incidence of complications, shorten hospital stay, cause less short-term pain after operation, and achieve faster recovery, which is beneficial to the early recovery of knee joint function.