A Biomechanical Comparison of Conventional versus an Anatomic Plate and Compression Bolts for Fixation of Intra-articular Calcaneal Fractures

The purpose of this study was to compare the biomechanical stability obtained by using our technique featured an anatomical plate and compression bolts versus that of the conventional anatomic plate and cancellous screws in the fixation of intraarticular calcaneal fractures.Eighteen fresh frozen lower limbs of cadavers were used to create a reproductive Sanders type-Ⅲ calcaneal fracture model by using osteotomy.The calcaneus fractures were randomly selected to be fixed either using our anatomical plate and compression bolts or conventional anatomic plate and cancellous screws.Reduction of fracture was evaluated through X radiographs.Each calcaneus was successively loaded at a frequency of 1 Hz for 1000 cycles through the talus using an increasing axial force 20 N to 200 N and 20 N to 700 N,representing the partial weight bearing and full weight bearing,respectively,and then the specimens were loaded to failure.Data extracted from the mechanical testing machine were recorded and used to test for difference in the results with the Wilcoxon signed rank test.No significant difference was found between our fixation technique and conventional technique in displacement during 20-200 N cyclic loading(P=0.06),while the anatomical plate and compression bolts showed a great lower irreversible deformation during 20-700 N cyclic loading(P=0.008).The load achieved at loss of fixation of the constructs for the two groups had significant difference:anatomic plate and compression bolts at 3839.6±152.4 N and anatomic plate and cancellous screws at 3087.3±58.9 N(P=0.008).There was no significant difference between the ultimate displacements.Our technique featured anatomical plate and compression bolts for calcaneus fracture fixation was demonstrated to provide biomechanical stability as good as or better than the conventional anatomic plate and cancellous screws under the axial loading.The study supports the mechanical viability of using our plate and compression bolts for the fixation of calcaneal fracture.

The Use of Calcaneal Anatomic Plate in Arthroscopically-assisted Open Reduction and Internal Fixation of Intra-articular Calcaneal Fractures

To discuss and evaluate the method and effect of using calcaneal anatomic plate in treatment of intra-articular fractures of the calcaneus with assistant of arthroscope, 86 intra-articular fractures of the calcaneus in 78 patients were reduced by open reduction, and rigid fixation was made with calcaneal anatomic plate under assistant of arthroscope. The average follow-up duration was 18 months （range 12-30 months）. The effect of treatment was evaluated according to AOFAS and X-ray before and after operation. The results showed that 86 patients have obtained satisfactory reduction according to X-ray, and there was significant difference before and after operation （P〈0. 01）, the total excellent and fine rate was 91.86%. Treating intra-articular fractures of the calcaneus with calcaneal anatomic plate under arthroscope may provide more chance to achieve anatomical reconstruction, which can lead to satisfied recovery of function and few complication.

Surgical Treatment for Proximal Humerus Fractures Comparison between Plate Fixation and Kapandji’s Pinning

Introduction: Proximal humerus fractures are common, however, there is no consensus on a decision-making algorithm for the therapeutic management of these fractures, the aim of this study is to evaluate and compare functional results between two surgical techniques and to deduce the satisfactory results of the Kapandji’s pinning which, compared to the screw plate, should keep its place in the therapeutic arsenal. Patients and Methods: It’s a retrospective study, including two groups: The first of 18 patients treated with palm-tree pinning using kapandji’s technique, the second of 16 patients treated with anatomical screw plate at the orthopedic trauma service of the Mohamed VI university hospital between July 2013 and July 2018. We compared the results of the two techniques by studying three parameters which are the healing time, the anatomical reduction, and the functional outcomes. The average age was 46 years, and the sex ratio (M/F) was 2.3. Results: The statistical analysis of functional and radiological results showed no significant difference between the two techniques, indeed the average healing time was 56.3 days in the group treated by screw plate and 55.2 days in the group treated by Kapandji’s pinning (p = 0.46), Constant’s score was 73.18 and 79.05 respectively (p = 0.27) and the average cephalodiaphyseal angle was 49.03° and 52.07°, respectively (p = 0.35). Discussion: This study has clearly shown, as reported in the literature, that there is no conclusive evidence to suggest superiority of os-teosynthesis by anatomical plate versus kapandji’s pinning. However, the simple achievement of pinning according to kapandji’s technique, the preservation of soft tissues and the low cost make us prefer this technique. Furthermore, despite the progress noted in the development of osteosynthesis means of the proximal humerus, percutaneous pinning should always keep its place.

A novel anatomical self-locking plate fixation for both-column acetabular fractures

Purpose:To compare the stability of the posterior anatomic self-locking plate(PASP)with two types of popular reconstruction plate fixation,i.e.double reconstruction plate(DRP)and cross reconstruction plate(CRP),and to explore the influence of sitting and turning right/left on implants.Methods:PASP,DRP and CRP were assembled on a finite element model of both-column fractures of the left acetabulum.A load of 600 N and a torque of 8 N·m were loaded on the S1 vertebral body to detect the change of stress and displacement when sitting and turning right/left.Results:The peak stress and displacement of the three kinds of fixation methods under all loading conditions were CRP>DRP>PASP.The peak stress and displacement of PASP are 313.5 MPa and 1.15 mm respectively when turning right;and the minimal was 234.0 Mpa and 0.619 mm when turning left.Conclusion:PASP can provide higher stability than DRP and CRP for both-column acetabular fractures.The rational movement after posterior DRP and PASP fixation for acetabular fracture is to turn to the ipsilateral side,which can avoid implant failure.