[Reduction techniques for minimally invasive stabilization of proximal humeral fractures]

Application of 3D modeling in a personalized approach to bone osteosynthesis (A literature review)

Three-dimensional printing opens up many opportunities for use in traumatology and orthopedics, because it takes into account personal characteristics of the patients. Modern methods of high-resolution medical imaging can process data to create threedimensional images for printing physical objects. Today, three-dimensional printers are able to create a model of any complexity of shape and geometry. The article provides a review of the literature about three-dimensional digital modeling in shaping implants for osteosynthesis. Data search was carried out on the Scopus, Web of Scince, Pubmed, RSCI databases for the period 2012–2022. The effectiveness of three-dimensional printing for preoperative modeling of bone plates has been confirmed: implants perfectly corresponds with the unique anatomy of the patient, since the template for it is based on the materials of computed tomography. Individual templates can be useful when the geometry of patients' bones goes beyond the standard, and when improved results of surgery are expected due to better matching of implants to the anatomical needs of patients. 

[Augmentation in the treatment of proximal humeral and femoral fractures]

BACKGROUND

Proximal humeral and trochanteric femoral fractures in older patients are typically caused by low-energy trauma and are therefore often associated with osteoporosis. The treatment of such fragility fractures can be difficult as implant purchase is reduced in osteoporotic bone. By augmenting the fixation with cement the contact surface between implant and bone can be increased, which improves the stability of the osteosynthesis.

OBJECTIVE

This article describes the operative technique for the augmentation of trochanteric femoral fractures treated with the Trochanteric Fixation Nail-Advanced (TFNA, DePuy Synthes, Oberdorf BL, Switzerland) and proximal humeral fractures stabilized with a PHILOS plate (DePuy Synthes). Furthermore, the evidence for the augmentation of these two fracture types is elucidated.

RESULTS

Biomechanical studies could show an improved stability of the osteosynthesis after successful augmentation for both fracture types. The current evidence also indicates a clinical reduction of fixation failure. Whether the augmentation has an influence on the functional result could so far not yet clearly be proven.

CONCLUSION

Augmentation seems to be a safe and valuable addition to available treatment options especially for patients with fragility fractures.

Why locking plates for the proximal humerus do not fit well

INTRODUCTION

We compared the angle of the humerus and plate and to assess compatibility of a plate to the proximal humerus using three-dimensional (3D) printed models.

MATERIALS AND METHODS

A total of 120 cases were included, who underwent anteroposterior shoulder radiographs. From these, 30 cases with 3D shoulder computed tomography scans were randomly selected to print 3D model. The lateral angle between the lateral cortex of the humeral shaft and lateral border of the greater tuberosity (GT), neck-shaft angle, and height from the most proximal point of the GT to the angular point were measured. When the plates were applied on the 3D models, the gap from the most proximal point of the GT to the proximal rim of the plate was measured.

RESULTS

The mean lateral angle in plain radiographs was 12.9 ± 2.2° and height from the most proximal point of the GT to the angular point was 44.4 ± 4.7 mm. The bending angles of the three plates were 8° and 10°. Height from the proximal rim of the plate to the bending point was 42.4, 42.0 and 43.8 mm. In 98% of cases, the lateral angle of the humerus was larger than all three plates. In 43% of cases, height of the GT was smaller than height of plates. When plates were applied to the 3D model, the mean gap from GT to plate was 4.8 ± 2.8 mm.

CONCLUSIONS

There was large variation in the lateral angle of the proximal humerus, which was not correlated with the neck-shaft angle. The lateral angle of the humerus was larger than the plates and prone to varus reduction and medial collapse.

LEVEL OF EVIDENCE OR CLINICAL RELEVANCE

Basic science study.

[Application of "door-shaft method" in limited open reduction and internal fixation with locking plate for two- and three-part fractures of the proximal humerus]

Objective

To investigate the effectiveness of limited open reduction via "door-shaft method" and internal fixation with locking plate for two- and three-part fractures of the proximal humerus.

Methods

The clinical data of 64 patients with proximal humeral fractures who were admitted between January 2013 and December 2016 and met the selection criteria were retrospectively analyzed. There were 23 males and 41 females, with an average age of 68.0 years (range, 50-89 years). The injuries were caused by falling in 57 cases, traffic accident in 5 cases, and falling from height in 2 cases. The interval between injury and operation was 1-7 days (mean, 2.1 days). According to Neer classification, there were 28 cases of two-part fractures and 36 cases of three-part fractures. According to the angulation direction of the proximal humeral neck shaft angle, there were 21 cases of adduction fractures and 43 cases of abduction fractures. The fractures were treated with limited open reduction via "door-shaft method" and proximal humerus internal locking systems for internal fixation. The operation time, intraoperative blood loss, number of fluoroscopy, hospital stay, and complications were recorded. The fracture healing was reviewed by X-ray film and the healing time was recorded. The shoulder joint function was evaluated by Neer score standard.

Results

The operation time was 45-127 minutes, with an average of 82.3 minutes. The intraoperative blood loss was 30-125 mL, with an average of 62.7 mL. Intraoperative fluoroscopy was performed 30-69 times, with an average of 37.0 times. The hospital stay was 6-23 days, with an average of 10.3 days. All incisions healed by first intention. All patients were followed up 12-37 months, with an average of 18.3 months. X-ray film re-examination showed that all fractures healed, the healing time was 12-21 weeks, with an average of 14.3 weeks. After operation, 3 cases had shoulder stiffness and 1 case had fracture malunion. At last follow-up, the Neer score of shoulder joint function was 49-97, with an average of 83.1. Among them, 38 cases were excellent, 13 cases were good, 10 cases were fair, and 3 cases were poor. The excellent and good rate was 79.7%. The excellent and good rate of patients with two-part fractures was 82.1% (23/28), and the excellent and good rate of patients with three-part fractures was 77.8% (28/36).

Conclusion

The "door-shaft method" not only reduces the difficulty of the Joystick technique in the reduction of proximal humerus fractures, but also provides auxiliary stability. It is used for limited open reduction and internal fixation with locking plate to treat the two- and three-part fractures of the proximal humerus, which can achieve good effectiveness.