Management of proximal humeral fractures in elderly patients with uni- or polyaxial locking osteosynthesis system

PHILOS Synthesis for Proximal Humerus Fractures Has High Complications and Reintervention Rates: A Systematic Review and Meta-Analysis

Purpose: The aim of this study was to quantify the rate of complications and reinterventions in patients treated with PHILOS plate for proximal humerus fractures (PHFs) synthesis. Methods: A comprehensive literature search was performed on the PubMed, Web of Science, Embase, and Cochrane databases up to 7 October 2021. Studies describing medium and long-term complications in PHF synthesis using the PHILOS plate were included. A systematic review and meta-analysis were performed on complications and causes of reinterventions. Assessment of risk of bias and quality of evidence was performed with the Downs and Black’s “Checklist for Measuring Quality”. Results: Seventy-six studies including 4200 patients met the inclusion criteria. The complication rate was 23.8%, and the main cause was screw cut-out (4.1%), followed by avascular necrosis (AVN) (3.1%) and subacromial impingement (1.5%). In patients over 55 years, the complication rate was 29.5%. In the deltopectoral (DP) approach the complication rate was 23.8%, and in the delto-split (DS) it was 17.5%, but no difference between the two approaches was seen when considering the type of fracture. The overall reintervention rate was 10.5% in the overall population and 19.0% in older patients. Conclusions: Proximal humerus synthesis with a PHILOS plate has high complications and reintervention rates. The most frequent complication was screw cut-out, followed by humeral head AVN and subacromial impingement. These results need to be further investigated to better understand both the type of patient and fracture that is more at risk of complications and reintervention and to compare pros and cons of the PHILOS plate with respect to the other solutions to manage PHFs.

Late screw-related complications in locking plating of proximal humerus fractures: A systematic review

Locking plating is a common surgical treatment of proximal humeral fractures with satisfactory clinical results. Implant-related complications, especially screw-related, have been reported, however, the lack of information regarding their onset, used surgical technique, complexity of the fracture, bone quality etc., prevents from understanding the causes for them. The aim of this systematic review is to identify the potential risk factors for late screw complications by gathering information about the patient characteristics, comorbidities, fracture types, surgical approaches and implant types. A PubMed search was performed using humerus, fractures, bone and locking as keywords in clinical papers written in English. All abstracts and manuscripts on distal or humerus shaft fractures, and those on proximal humerus fractures without any or with only iatrogenic complications were excluded. One hundred studies met the inclusion criteria, resulting in 33% of the reported cases having at least one complication, with 11% of all complications being screw-related. Most of the latter were secondary screw perforations and screw cut-outs, being predominantly linked to poor bone quality, while screw loosening and retraction were found less frequently as a result of locking mechanism failure. Overall, the amount of information for complications was limited and screw perforation was the most frequent screw-related complication, mostly reported in female patients older than 50 years, following four-part or AO/OTA type C fractures and detected four weeks postoperatively. The sparse information in the literature could be an indicator that the late screw complications might have been under-reported and under-described, making the understanding of the screw-related complications even more challenging.

Treatment of humerus fractures in the elderly: A systematic review covering effectiveness, safety, economic aspects and evolution of practice

OBJECTIVES

The objective of this Health Technology Assessment was to evaluate effectiveness, complications and cost-effectiveness of surgical or non-surgical treatment for proximal, diaphyseal or distal fractures of the humerus in elderly patients. Secondary objectives were to evaluate the intervention costs per treatment of proximal humerus fractures (PHF) and to investigate treatment traditions of PHF in Sweden.

METHODS AND FINDINGS

The assessment contains a systematic review of clinical and health economic studies comparing treatment options for humerus fractures in elderly patients. The results regarding the effectiveness of treatments are summarized in meta-analyses. The assessment also includes a cost analysis for treatment options and an analysis of registry data of PHF. For hemiarthroplasty (HA) and non-operative treatment, there was no clinically important difference for moderately displaced PHF at one-year follow-up regarding patient rated outcomes, (standardized mean difference [SMD]) -0.17 (95% CI: -0.56; 0.23). The intervention cost for HA was at least USD 5500 higher than non-surgical treatment. The trend in Sweden is that surgical treatment of PHF is increasing. When functional outcome of percutaneous fixation/plate fixation/prosthesis surgery and non-surgical treatment was compared for PHF there were no clinically relevant differences, SMD -0.05 (95% CI: -0.26; 0.15). There was not enough data for interpretation of quality of life or complications. Evidence was scarce regarding comparisons of different surgical options for humerus fracture treatment. The cost of plate fixation of a PHF was at least USD 3900 higher than non-surgical treatment, costs for complications excluded. In Sweden the incidence of plate fixation of PHF increased between 2005 and 2011.

CONCLUSIONS

There is moderate/low certainty of evidence that surgical treatment of moderately displaced PHF in elderly patients has not been proven to be superior to less costly non-surgical treatment options. Further research of humerus fractures is likely to have an important impact.

Locking Cap Designs Improve Fatigue Properties of Polyaxial Screws in Upper Extremity Applications

OBJECTIVES

This study sought to examine fatigue characteristics of 2 polyaxial locking screw designs: locking cap (LC) and cross-threaded (CT). The goal was to compare LC and CT implants at 0, 10, and 15 degrees of angulation to determine the effect of locking mechanism on screw-plate interface failure. The hypothesis was that LC implants would have superior fatigue properties in comparison to CT designs and that increased angulation of the screw would have a negative impact on the fatigue life of CT implants, but would not have any effect on LC implants.

METHODS

A total of 72 screws were tested in 4 upper extremity implants. Implants were subjected to cyclic shear loads and subsequent ramp to failure. Performance characteristics were statistically compared using nonparametric statistical methods.

RESULTS

Fatigue testing demonstrated that LC designs were consistently able to sustain a significantly higher number of cyclic loads than CT designs. There were no significant differences in the number of cycles sustained by LC designs because of changes in screw angle, but CT implants exhibited decreases in screw stability with increasing angulation.

CONCLUSIONS

Likely because of the spherical screw head geometry, LC fatigue characteristics are not influenced by the orientation of the screw relative to the plate. Application of an LC in the operating room requires additional time, but provides significantly more robust fixation of the screw, especially at oblique angles to the plate and provides a more predictable and consistent biomechanical result.

The treatment of complex proximal humeral fractures: analysis of the results of 55 cases treated with PHILOS plate

Complex proximal humerus fractures are often difficult to treat. Their frequency is high, especially in the elderly, and their treatment is still controversial. The aim of this study was to analyze the clinical and radiological results achieved by patients with complex proximal humerus fractures, treated with PHILOS plate only. A cohort of 55 patients was selected. The mean age was 63.4 (range 33-89), while the mean follow-up time was 21.5 months (range 6-75). Clinical outcome was evaluated with the "Constant-Murley shoulder score." All the informations about the presence of complications were gathered, and radiological images were used to calculate the head-shaft angle. The overall mean Constant score was 61.93 ± 18.59, the Individual CS was 70 ± 20 % and the Relative CS was 83 ± 23 %. No significant differences were found between fractures Neer 3 and Neer 4 and between the surgical approaches (delta-split vs. delto-pectoral). Six patients had a fracture with dislocation, seven patients (12.7 %) had complications while in four patients a head-shaft angle beyond the normal range was found. Osteosynthesis with PHILOS plate is stable in the greater part of the cases, and it allows an earlier rehabilitation and so a good functional result, which could be compromised by a prolonged immobilization. Therefore, PHILOS plate is a good option for the treatment of complex proximal humerus fractures.

Anatomical study of simple landmarks for guiding the quick access to humeral circumflex arteries

Background

The posterior and anterior circumflex humeral artery (PCHA and ACHA) are crucial for the blood supply of humeral head. We aimed to identify simple landmarks for guiding the quick access to PCHA and ACHA, which might help to protect the arteries during the surgical management of proximal humeral fractures.

Methods

Twenty fresh cadavers were dissected to measure the distances from the origins of PCHA and ACHA to the landmarks (the acromion, the coracoid, the infraglenoid tubercle, the midclavicular line) using Vernier calipers.

Results

The mean distances from the origin of PCHA to the infraglenoid tubercle, the coracoid, the acromion and the midclavicular line were 27.7 mm, 50.2 mm, 68.4 mm and 75.8 mm. The mean distances from the origin of ACHA to the above landmarks were 26.9 mm, 49.2 mm, 67.0 mm and 74.9 mm.

Conclusion

Our study provided a practical method for the intraoperative identification as well as quick access of PCHA and ACHA based on a series of anatomical measurements.

Outcomes After Fixation of Proximal Humerus (OTA Type 11) Fractures in the Elderly Patients Using Modern Techniques

PURPOSE

To investigate the effects of age on the clinical, functional, and radiographic outcomes of patients with proximal humerus fractures treated operatively with locking plates.

METHODS

Between February 2003 and July 2012, all patients who sustained a proximal humerus fracture who presented to our institution were enrolled into a database. Patients were followed up at 1, 6, 12, 26, and 52 weeks postoperatively with physical examination and radiographs. Validated functional outcomes scores were collected at 6 and 12 months. Complications were recorded as they occurred. Statistical analysis was conducted to assess for functional, physical, or radiographic differences between patients age younger than 65 and patients age 65 or older.

RESULTS

Of the 147 consecutive patients treated operatively for a proximal humerus fracture, 115 (78%) patients with an average follow-up of 16 months met the inclusion criteria for this study. The young cohort (patients < 65) included 70 patients with an average age of 53, whereas the elderly cohort (patients ≥ 65) included 45 patients with an average age of 73. The older cohort had significantly more women (P = .04), but there was no statistical difference in fracture type between the age groups. There were no differences in the radiographic measures of screw penetration, humeral head height, and neck-shaft angle between the age groups. There were no differences in physical examination scores between the age groups. There were no significant differences in functional outcomes or complication rates between the age groups.

CONCLUSION

Treating proximal humerus fractures operatively with locked plates can overcome the challenges of poor bone quality that often occur with increasing age. Age should not play a significant role in the decision-making process for treating proximal humerus fractures that would otherwise be indicated for surgical fixation.

Open reduction internal fixation of proximal humerus fractures

The treatment of proximal humerus fractures continues to evolve. While the many of these injuries can be managed nonoperatively, a certain percentage require operative treatment. Open reduction internal fixation can offer excellent outcomes when performed in the appropriate patient and utilizing proper techniques. This article reviews the most up-to-date literature regarding all phases of proximal humerus fracture osteosynthesis, including diagnosis, imaging, anatomic considerations, surgical indications, fixation, and surgical outcomes.

A comparison of parallel and diverging screw angles in the stability of locked plate constructs

We investigated the static and cyclical strength of parallel and angulated locking plate screws using rigid polyurethane foam (0.32 g/cm(3)) and bovine cancellous bone blocks. Custom-made stainless steel plates with two conically threaded screw holes with different angulations (parallel, 10° and 20° divergent) and 5 mm self-tapping locking screws underwent pull-out and cyclical pull and bending tests. The bovine cancellous blocks were only subjected to static pull-out testing. We also performed finite element analysis for the static pull-out test of the parallel and 20° configurations. In both the foam model and the bovine cancellous bone we found the significantly highest pull-out force for the parallel constructs. In the finite element analysis there was a 47% more damage in the 20° divergent constructs than in the parallel configuration. Under cyclical loading, the mean number of cycles to failure was significantly higher for the parallel group, followed by the 10° and 20° divergent configurations. In our laboratory setting we clearly showed the biomechanical disadvantage of a diverging locking screw angle under static and cyclical loading.