To explore the effect of new barbed suture on early function and pain after primary total knee arthroplasty.

From January 2017 to January 2018, 82 patients with first TKA operation in orthopaedics department of the Fourth Affiliated Hospital of Harbin Medical University were selected(inclusion criteria: valgus deformity <20 °, BMI <35 kg/m²; exclusion criteria: poor skin condition, patients with primary or secondary lower extremity vascular disease, knee joint stiffness, recent intra-articular drug injection or small needle knife therapy, long-term use of immunosuppressive agents, cell inhibitors, hormones or anticoagulants, and incomplete case data). According to the different ways of incision suture, they were divided into the barbed suture group and the routine suture group. The knee joint function and pain of the two groups were evaluated within three months, and the perioperative conditions of the two groups were recorded. The measurement data were compared by t-test and counted data were analyzed by chi-square test.

There was no significant difference in incision length, tramadol usage, average hospitalization time and postoperative complications between the two groups (P >0.05); the suture time and intraoperative drainage volume in the barbed suture group were significantly less than those in the conventional suture group (t=2.713, 4.896, P <0.05). The visual analogue scale (VAS) score of the two groups were significantly improved after the operation and showed a downward trend. The VAS score of the routine suture group was significantly lower than that of the barbed suture group at the 3^rd day, one week, and two weeks postoperatively (t=3.235, 4.359, 4.269, P <0.05). There was no significant difference in VAS score between the two groups at six weeks and 12 weeks after the operation (P >0.05). The Hospital for Special Surgery (HSS) score and range of motion(ROM )of the two groups increased significantly after the operation, and the HSS score and ROM of the conventional suture group were higher than those of the barbed suture group at the 3^rd day, one week, and two weeks postoperatively (t=3.374, 2.487, 3.803, t =3.300, 2.068, 2.356, P<0.05). There was no significant difference in HSS score and ROM between the two groups at six weeks and 12 weeks after operation (P>0.05).

The TKA incision closed with a new type of barbed suture presents strong pain, poor knee joint mobility and functional recovery during functional exercise within two weeks after the operation. The curative effect at six and 12 weeks after the operation is basically the same as that of the conventional suture. The new barbed suture can significantly shorten the suture time and reduce the amount of bleeding during the operation, and has no obvious benefit in reducing incision complications, resting pain or shortening hospital stay.