Reduction and Fixation of Proximal Humeral Fracture With Severe Medial Instability Using a Small Locking Plate

Background Currently, the reduction and support of comminuted medial cortex of humeral fracture remains a challenge, Therefore, a novel reduction and fixation technique that employs an anteromedial small locking plate was explored in this study, and its viability and the associated complications were assessed. Methods Fifteen cases of proximal humeral fractures with medial instability (five cases were classified as three-part and ten as four-part by Neer classification) were treated by the proposed reduction technique using an anteromedial small locking plate. Subsequently, the radiological and clinical outcomes were evaluated over an average follow-up period of 18.53 months. Results The average operation time was 108 minutes (range, 70–130 minutes), and the mean fracture union time in all patients was 12.13 weeks (range, 8–16 weeks). Complications such as infection and neurovascular injury were not observed. Postoperative X-ray showed avascular necrosis and screw penetration in one patient, while screw penetration, varus malunion, or significant reduction loss was not found in the other cases. The mean Constant score was 79.8 (range, 68–92) during the final visit. Conclusions The use of an anteromedial small locking plate improved the reduction efficiency, reconstructed the medial support, and alleviated the occurrence of complications in proximal humeral fractures with medial instability.

P.224 A Case Report of Spinal Screws Penetrating the Pulmonary Artery

Background: Spinal instrumentation is commonly utilized to mechanically stabilize the spine in trauma, oncology and degenerative disease. Although several complications have been reported, this is the first case of screw penetration of the pulmonary artery. Methods: We present a case of a 74-year old gentleman who suffered from a thoracic spine chordoma. He underwent a T8 resection with T8-T12 instrumented fusion with subsequent radiation. Recurrence of his disease led to resection of his 3rd and 4th ribs and repeat radiation. He presented 6 years later with 2 episodes of massive hemoptysis. Review of the literature was conducted to search for similar complications. Results: A Chest Computed Tomography scan demonstrated the presence of a pedicle screw tip in the right pulmonary artery. Angiogram revealed no evidence of active arterial extravasation. In the operating room, the patient had a right lower lobectomy, with segmental pulmonary artery sacrifice, as well as replacement of the spinal fixation hardware. Literature review revealed multiple aortic injuries following spinal instrumentation. However, this was the first case of pulmonary artery erosion. Conclusions: Spinal instrumentation has been associated with screw migration and penetration of nearby tissues and vessels. A high incidence of suspicion is required when patients present with delayed and unusual complications.

Reduction and fixation of proximal humeral fracture with severe medial instability using a small locking plate

Background Currently, the reduction and support of comminuted medial cortex of humeral fracture remains a challenge, Therefore, a novel reduction and fixation technique that employs an anteromedial small locking plate was explored in this study, and its viability and the associated complications were assessed. Methods Fifteen cases of proximal humeral fractures with medial instability (five cases were classified as three-part and ten as four-part by Neer classification) were treated by the proposed reduction technique using an anteromedial small locking plate. Subsequently, the radiological and clinical outcomes were evaluated over an average follow-up period of 18.53 months. Results The average operation time was 108 min (range, 70–130 min), and the mean fracture union time in all patients was 12.13 weeks (range, 8–16 weeks). Complications such as infection and neurovascular injury were not observed. Postoperative X-ray showed avascular necrosis and screw penetration in one patient, while screw penetration, varus malunion, or significant reduction loss was not found in the other cases. The mean Constant score was 79.8 (range, 68–92) during the final visit. Conclusions The use of an anteromedial small locking plate improved the reduction efficiency, reconstructed the medial support, and alleviated the occurrence of complications in proximal humeral fractures with medial instability.

3D virtual pre-operative planning may reduce the incidence of dorsal screw penetration in volar plating of intra-articular distal radius fractures

Purpose To evaluate the effect of three-dimensional virtual pre-operative planning (3DVP) on the incidence of dorsal screw penetration after volar plating of distal radius fractures. Methods A cross-sectional diagnostic imaging study was performed. Twenty out of 50 patients were randomly selected from our index prospective cohort (IPC): a prior study evaluating dorsal tangential views (DTVs) in reducing dorsal screw penetration in internal fixation of intra-articular distal radius fractures using post-operative CT scans to quantify screw protrusion. Pre-operative CTs from this cohort were now used for 3DVP by three experienced orthopaedic trauma surgeons (supplementary video). 3DVP was compared with the corresponding post-operative CT for assessing screw lengths and incidence of dorsal penetration. The Wilcoxon Signed Ranks test was used to compare screw lengths and the Fishers’ exact for incidence of penetration. Results Three surgeons performed 3DVP for 20 distal radius fractures and virtually applied 60 volar plates and 273 screws. Median screw length was shorter in the 3DVP when compared to IPC: 18 mm (range, 12–22) versus 20 mm (range, 14–26) (p < 0.001). The number of penetrating screws was 5% (13/273 screws) in the 3DVP group compared to 11% (10/91 screws) in the IPC (p = 0.047). Corresponding to a reduction in incidence of at least one dorsally penetrating screw in 40% of patients in the IPC group, to 18% in the 3DVP group (p = 0.069). Conclusion Three-Dimensional Virtual Pre-Operative Planning (3DVP) may reduce the incidence of dorsally penetrating screws in patients treated with volar plating for intra-articular distal radius fractures. Level of evidence II, diagnostic imaging study.

Prediction of Accuracy and Screw Size by Pedicle Anatomic Parameters and Screws in Idiopathic Scoliosis With Freehand Screw Placement Based on Machine Learning

Study Design: A retrospective study.Objective: To investigate a machine learning algorithm to explore the influence of pedicle morphological parameters and pedicle screw size on safe screw placement in the treatment of idiopathic scoliosis with freehand. And a model was built to guide the selection of screwMethods: We analyzed 52 patients with idiopathic scoliosis who underwent correction surgery in our hospital from June 2012 to December 2019, including 17 males and 35 females aged 10-20 years. All pedicle screws were placed by freehand. Preoperative and postoperative X-ray and CT scans of whole spine were performed to measure Cobb Angle and pedicle morphological parameters, including transverse diameter of the pedicle, sagittal diameter of the pedicle, length of the pedicle channel, rotation angle of vertebrae, angle of the sagittal plane of pedicle and angle of the horizontal plane of pedicle. Screw penetration grading was also evaluated. Random forest were used to build a machine learning model to help the decision making of choosing an appropriate screw based on pedicle parameters and screw size.Results: A total of 888 screws and pedicles were included. The satisfactory rate of screw placement was 88.5%. The pedicle screw size was analyzed and predicted based on screw penetration and pedicle morphological parameters. The AUROC of random forest classification model achieved 0.712. The goodness of fit(R2) was 0.546.Conclusion: Our model could provide guidance for the doctor to choose the length of the screw before surgery, and the classification model could also give a preliminary prediction of whether there would be anterior screw penetration based on the pedicle parameters.

The prevention of penetration of unidentified screw of femoral neck fracture during the operation

BackgroundScrew internal fixation is one of the main surgical procedures for femoral neck fractures. Routine intraoperative fluoroscopy is hard to identify screw penetration, which becomes one of the important factors of postoperative hip pain and postoperative complications.MethodsCollect and analyze the intraoperative and postoperative imaging data of patients with internal fixation. Using geometric methods and analysis of anatomical characteristics, we explored the best imaging angle where the screw penetration was not found in the conventional 2D images of the anterior and lateral view during the operation, so that it can be determined whether there is screw penetration by taking a certain angle during the operation.ResultsThe unrecognized screw penetration rate during the operation was 25%, 5% penetrated from the back of the femoral head, and 20% penetrated the femoral neck part and then entered the head. The unrecognized screw of the femoral head is caused by the intersection of the anterior and lateral projection to form the Steinmetz solid. The study found that the special photographic orientation θ=90°—arctan (M1O′/M2O′). For the screw penetration of the femoral neck, the probability of occurrence in different areas of the femoral neck is 10.5% of the front superior part, 44.2% of the front inferior part, 28.6% of the back superior part, and 16.8% of the back inferior part. The best shooting directions of the front superior,front inferior, back superior, and back inferior through which the detection screw passes are the positive position ,35.8° to the tail side, 70° to the head side, 46.3° to the head side, and 40.5° to the tail side.ConclusionIt is important to avoid unrecognized screw penetration during the operation. In this study, it was concluded that a certain angle was taken during the operation to determine whether there was screw penetration, which significantly reduced the incidence of screw penetration of the femoral head and femoral neck.