Objective To compare the radiographic and clinical outcomes of uniaxial and polyaxial locking plates used in the treatment of complex intraarticular calcaneal fractures.Methods A retrospective comparative study was performed on the 50 patients with intraarticular calcaneal fracture (Sanders types Ⅲ and Ⅳ) who had been treated by uniaxial locking plates (n =26) or polyaxial locking plates (n =24) between January 2013 and June 2015.Operation time,intraoperative bleeding,union time,radiological and functional outcomes and functions by the Maryland foot score were compared between the 2 groups.Results All the patients were followed up for 12 to 44 months(average,20.8 months).There were no significant differences between the 2 groups in average operation time (105.2 ± 18.2 min versus 95.5 ± 17.7 min),average intraoperative bleeding (125.2 ±23.4 mL versus 120.3 ±21.5 mL),or union time (12.1 ± 3.7 weeks versus 11.8 ± 3.7 weeks) (P ＞ 0.05).All patients obtained bony union.The polyaxial locking plates group displayed significantly better B(o)hler and Gissane angles at 3 and 12 months after operation than the uniaxial locking plates group (P ＜ 0.05).Evaluated by the Maryland foot score,the excellent and good rate for the polyaxial locking plates group [91.7％ (22/24)] was insignificantly higher than that for the uniaxial locking plates group [84.6％ (22/26)] (P =0.267).Conclusions Both uniaxial locking and polyaxial locking plates can lead to satisfactory therapeutic outcomes for complex intraarticular calcaneal fractures,but polyaxial locking plates may be superior in stability and functional recovery.

BACKGROUND:Whether lumbar spondylolisthesis needs to be treated with reduction remains controversial.OBJECTIVE:To investigate the clinical effectiveness of pedicle screw fixation combined with posterior lumbar interbody fusion for degenerative lumbar spondylolisthesis in the patients aged more than 70 years old.METHODS:The clinical data of 30 patients with degenerative spondylolisthesis aged over 70 years old undergoing pedicle screw fixation combined with posterior lumbar interbody fusion were analyzed retrospectively.The Visual Analogue Scale,Oswestry Dysfunction Index and the Japan Orthopedics Association scores were compared and analyzed before and after surgery.RESULTS AND CONCLUSION:(1) Among 30 patients,12 were male and 18 female,the average age was (75.1±6.7) years old,and all were followed up for more than 12 months.(2) The postoperative Visual Analogue Scale,Oswestry Dysfunction Index and the Japan Orthopedics Association scores were significantly improved compared with baseline (P ＜ 0.05).According to the Japan Orthopedics Association scores,3 cases were cured,24 were significantly effective,and 3 effective.(3) Graft fusion was achieved at all patients,the average fusion time was (5.13±0.65) months.(4) The average operation time was (225.6±23.4) minutes,the average intraoperative blood loss was (470±45.5) mL,and the average follow-up time was (25.8±3.5) months.(5) Six patients presented complications (20％),including one case of dural tear,two cases of paralytic intestinal obstruction,and three transient lower extremity nerve symptoms.(6) These results indicate that if the associated disorders are strictly controlled,pedicle screw fixation combined with posterior lumbar interbody fusion can achieve good surgical results in the treatment of degenerative spondylolisthesis in the elderly.

Objective To investigate the impact of various distribution of bone cement on the early clinical outcomes in osteoporotic vertebral compression fracture (OVCF) patients treated with percutaneous kyphoplasty (PKP).Methods A total of 312 patients (54 males and 258 females,mean age 69.37 years) who diagnosed as OVCF and received PKP treatment from January 2015 to July 2017 were enrolled in the present study.All subjects were divided into two groups according to different distribution of bone cement:the shaped "O" distribution (group O,113 cases),in which bone cement in the vertebral body presented whole crumb,no separation or loss of bone cement,and the shaped "H" distribution (group H,199 cases),in which bone cement in the vertebral body presented two briquettes,connected with or without a small amount of bone cement.Demographic data,surgical details,radiographic data,and clinical outcomes (at preoperatively,two-days and one-year follow-up) were compared between the two groups.Results There was no significant difference in bone mineral density (BMD),operation duration,blood loss,and occurrence of leakage of bone cement between two groups.In comparison with group O,group H was accompanied with higher volume of injected bone cement and higher proportion of bilateral approach (P＜0.05).Both groups achieved significant improvement of VAS scores after surgery,while the group H had a dramatical reduction of VAS scores at one-year follow-up compared with two-days follow-up (P＜0.05).In addition,group H had a better restoration of VAS scores at one-year follow-up than group O (P＜0.05),though no significant difference was observed at preoperative and two-days follow-up.Both groups achieved significant improvement of radiographic data after surgery (P＜0.05) with similar effects of correction.Conclusion Either shaped "H" or shaped"O" distribution of bone cement can obtain satisfied early clinical effects of PKP for the treatment of OVCF.Compared with shaped "O" distribution,shaped "H" distribution can achieve better pain relief at early follow-up.