Objective To explore the treatment methods of periprosthetic femur fracture after hip arthroplasty.Methods 9 patiens with periprosthetic femur fracture after hip arthroplasty were selected.According to Vancouver classification,there were 1 case in A type,5 cases in B1 type,2 cases in B2 type,1 case in C type.One case were treated by nonoperative method and the other 8 cases were treated by operative method,including 5 cases treated by memory alloy embracing fixator and internal fixation,3 cases treated by long stem prosthetic replacement and iliac bone graft.Results 8 cases were followed up for 8 to 21 months,average 14.2 months.All fractures were united well with good alignment and internal fixation failure except one prosthesis loosing was observed.Conclusion For periprosthetic femur fracture after hip arthroplasty,Vancouver classification methods include the location and stability of the fracture,prosthesis loosening,and the femur in bone mass is importance to the clinical treatment.As to A type fracture,prosthesis is stable,and the conservative treatment can be choosed.As to B1 and B2 type fracture,the aggressive surgical treatment can be choosed based on patients' general condition.If prosthesis loosening after artificial hip arthroplasty,the patients should treated with long stem prosthetic replacement.

Objective:To investigate the effect of three-dimensional printing technique assisted knee arthroplasty in the treatment of knee osteoarthritis with extraarticular deformities.Methods:Twelve patients with knee osteoarthritis and extraarticular deformities in the Sixth People's Hospital of Fuyang were selected as the study subjects from January 2016 to June 2018, and all patients were treated with total knee arthroplasty assisted by 3D printing.The operation time, intraoperative blood loss, preoperative simulated osteotomy value, intraoperative osteotomy value, postoperative drainage volume, joint activity score and Hospital for Special Surgery (HSS) score before treatment, 6 months after replacement and at the last follow-up were observed.Results:The intraoperative blood loss of patients was an average of (389.9±32.6)mL, and the drainage volume of patients was an average of (405.2±85.4)mL.There were no statistically significant difference between preoperative analogue value and intraoperative osteotomy value (all P>0.05). The HSS score ( P<0.001) and knee joint mobility ( P<0.001) were significantly higher at 6 months after operation and the last follow-up, and the mechanical axis deviation of lower limbs was significantly lower than that before operation ( P<0.001). Conclusion:Treatment of knee osteoarthritis with extra-articular deformity by using 3D printing assisted technique can restore the lower limbs and promote the recovery of knee joint function, which has satisfactory short-term effect and deserves further study and discussion.