Objective To study the clinical effects of uncemented long-stem hemiarthroplasty for the treatment of comminuted intertrochanteric fractures in elderly patients.Methods Included in this retrospective study were 36 senile patients with comminuted intertrochanteric fracture who had been treated from September 2012 to July 2014.They were 16 males and 20 females with an average age of 86.4 years (from 80 to 94 years).All the fractures were single-sided.According to the Evans-Jensen classification,15 cases were type Ⅲ,12 type Ⅳ and 9 type Ⅴ.According to the Singh index,their osteoporosis was classified as grade Ⅳ in 13 cases,as grade Ⅲ in 14 and as grade Ⅱ in 9.The Harginge approach was used in all the patients and hemiarthroplasty was performed using the uncemented long-stem Wagner SL prosthesis.Results For this cohort,the operation time ranged from 35 to 55 min (average,43.5 min),and the intraoperative blood loss from 200 to 320 mL (average,240 mL).All the incisions healed by the first intention.Postoperatively,respiratory system infection occurred in one case but was cured after symptomatic treatment.One patient died 3 months after operation.The follow-up time for the rest 35 patients ranged from 14 to 20 months (average,16 months).The average Harris score was improved from preoperative 28.3 points to 84.3 points at the final follow-up;the Harris scoring resulted in 24 excellent cases,8 good ones and 3 fair ones (with an excellent and good rate of 88.9％).There were no such complications during the follow-up as joint dislocation,prosthesis loosening or subsidence,or articular infection.Conclusion Hemiarthroplasty using the uncemented long-stem Wagner SL prosthesis is a fine treatment for elderly patients with comminuted intertrochanteric fracture,owing to the advantages of quick recovery,improved quality of life,reduced complications following prolonged bed rest and satisfactory short-term outcomes.

Objective:To evaluate the application of a 3D printed positioner for hip rotation center in total hip arthroplasty.Methods:From August 2015 to December 2017, 14 patients were treated by unilateral total hip arthroplasty at Department Ⅰ of Joint Surgery, Orthopaedics Hospital of Zhengzhou for avascular necrosis of femoral head or femoral neck fracture. They were 8 males and 6 females with an average age of 51.8 years (from 37 to 65 years). All their surgeries were assisted by a 3D printed positioner for hip rotation center. Postoperatively, the abduction and anteversion of acetabular cup and the hip rotation center were measured, the agreement between the hip rotation center of the affected side (O2) and the anatomical rotation center of the healthy side (O1) was assessed, and the function of the affected hip and complications were recorded at the last follow-up.Results:The 14 patients were followed up for an average of 18 months (from 6 to 24 months). The postoperative ordinates of O2 and O1 were respectively 19.36 mm±3.61 mm and 18.33 mm±3.41 mm while their abscissas 39.93 mm±2.97 mm and 39.99 mm±3.16 mm, indicating agreement between O2 and O1 ( P>0.05). The postoperative abduction and anteversion of the cup were within a normal range (39.3°±3.2°and 14.6°±1.2°, respectively). The last follow-up showed that their preoperative Harris hip scores (42.3±3.2) were significantly improved (94.3±4.7) ( t=2.873, P=0.002) and that 13 cases were rated as excellent and one as good. X-ray follow-up showed good position of their acetabular prostheses, no loosening of the cups or femoral prostheses, and no heterotopic ossification. Conclusion:A 3D printed positioner for hip rotation center can effectively assist reconstruction of the hip rotation center and accurate implantation of acetabular prosthesis in total hip arthroplasty.

Objective:To evaluate the application of 3D printed osteotomy template in total knee arthroplasty (TKA) for valgus knee.Methods:A retrospective analysis was performed of the 21 patients with valgus knee who had undergone TKA at Department Ⅰ of Joint Surgery, Orthopaedics Hospital of Zhengzhou from March 2016 to February 2018. They were 5 males and 16 females, aged from 62 to 78 years (average, 66.7 years). TKA was performed with the assistance of a 3D printed personalized osteotomy template for each patient. The efficacy of the personalized osteotomy templates was evaluated by comparing the femorotibial angle, knee range of motion, Hospital for Special Surgery (HSS) knee scores of the patients between preoperation and postoperation.Results:The 21 patients were followed up for a mean duration of 16.3 months(range, from 10 months to 4 years). All incisions healed by the first intention. The last follow-ups showed that their preoperative femorotibial angle 17.6°±5.7° was improved significantly to 6.3°±1.2°, their preoperative knee range of motion 71.3°±5.8° increased significantly to 102.4°±7.5°, and their preoperative HSS scores 38.2±5.7 increased significantly to 87.5±3.5 ( P<0.001). Their radiographic evaluation at the last follow-up showed stable prosthetic components with no implant loosing or osteolysis. Conclusion:A personalized 3D printed osteotomy template can be used in TKA for valgus knee, leading to accurate osteotomy, effective correction of mechanical alignment and satisfactory clinical outcomes.