[Objective]To explore the cause and treatment of refractory nonunion of patella combined with handicapped joint function.[Method]Retrospective analysis was given to twenty-four patients diagnosed as patellar nonunion that had been admitted to our hospital from Jan 1992 to Jan 2006.The series included fifteen males and nine females with an average age of 36(range 12-71) years.Initial treatment of the original fractures was nonoperative in 3,cerclage with wiring or suture silk in 11,tension band wiring in 6 and modified tension band wiring in 4.All fractures progressed to symptomatic nonunion at an average of 18 months from original injury(range 5-32).All patients were given open reduction and internal fixation,which consisted of Nickel-Titanium patella concentrator(NT-PC) in 9,NT-PC combined with cannulated compression screws in 6,combined with Kirschner wire in 5 and tension band wiring in 4.[Result]Twenty-four patients were followed up with an average of 35(range 6-168) months.The time of bone union averaged 4.2(range 3-6) months.No bone block displacement,loosening or breakage of internal fixation happened.According to Xu Shaoting' s knee function scores,the results were excellent in 14 cases,good in 6 cases,fair in 3 cases and poor in 1 cases.The excellent and good rate was 83.3%.[Conclusion]Operative reconstruction of smooth joint surface,rigid internal fixation and early functional exercise are effective remedies to refractory nonunion of patella combined with handicapped joint function.

Objective To assess the efficacy of internal fixation assisted with Halo-vest in the treatment of Anderson-D'Alonzo type Ⅱ and superficial type Ⅲ odontoid fractures.Methods A retrospective case series study was made on 15 patients clinically diagnosed as Anderson-D'Alonzo type Ⅱ and type Ⅲ odontoid fractures with a fracture gap over 2 mm,displacement over 5 mm and broken end angel over 11° from January 2007 to January 2015.There were nine males and six females,aged 27-61 years [(44.5 ± 10.9)years].The patients were treated in "three phases" with the assistance of Halo-vest external fixation system and a novel guide pin aiming device.The three phases were as follows:phase Ⅰ:cervical traction reduction and halo-vest external fixation;phase Ⅱ:Halo-vest assisted internal fixation using the novel aiming device;phase Ⅲ:the Halo-vest fixation removal and cervical collar fixation.Operation duration,intraoperative bleeding,and postoperative visual analogue scale (VAS) pain score one month after the operation were recorded.The cervical lateral and open mouth X-ray or atlantoaxial CT scan with sagittal and coronal two-dimensional reconstruction were regularly reviewed,and the location of screws,reduction and fracture healing were evaluated.Results Operation duration ranged from 54 to 96 minutes [(71.3-± 11.9) min].The intraoperative blood loss was 5-60 ml [(32.6 ± 16.8) ml].There was no spinal cord or nerve root injury,cerebrospinal fluid leakage,wound infection or other complications.All patients were followed up for 12-36 months (mean,28 months).Fourteen patients were seen bony union 6 months after the surgery and one patient was seen a false joint.At the last follow-up,the patient with false joint was seen bone sclerosis,and other patients with sound bone healing.The preoperative VAS and that of one month after the operation was (7.3 ± 0.6) points and (1.6 ± 0.7) points,respectively (P ＜ 0.05).Conclusion For Anderson-D'Alonzo type Ⅱ and type Ⅲ odontoid fractures,which have a fracture gap greater than 2 mm,displacement more than 5 mm,broken end angle above 11 degrees,the three-phase Halo-vest assisted internal fixation can provide good stability before operation and promote bone healing and pain relief after operation.