Cement augmentation of the proximal humerus internal locking system in elderly patients: a multicenter randomized controlled trial

Reverse total shoulder arthroplasty versus locked plate fixation for proximal humeral fractures in the elderly: a systematic review

INTRODUCTION

For surgical treatment of proximal humeral fractures (PHF) in older patients, there is no consensus if locked plate fixation (LPF) or reverse total shoulder arthroplasty (RTSA) yields better clinical results. The purpose of this study was to systematically review the clinical and functional outcomes of LPF and RTSA. We hypothesized that RTSA would outperform LPF in patients with PHF aged 65 years or older.

MATERIALS & METHODS

A comprehensive literature search was performed on PubMed and Google Scholar from 1 July 2022 up to 12 January 2024 by two independent reviewers. Comparative studies reporting on the functional outcome using the Constant-Murley score (CMS) in patients aged 65 years or older, treated after 2012 for PHF with LPF or RTSA and with a mean follow-up time of at least 12 months were included. Ten studies with 244 LPF and 287 RTSA patients were included into the statistical analysis. We used a frequentist network meta-analysis to assess the comparative effectiveness of the treatments. Individual risk of bias of the studies was assessed using the ROB2 and ROBINS-I tools.

RESULTS

Our network meta-analysis of the CMS resulted in the following order ranked from lowest to highest: LPF, LPF +  screw augmentation, hemiarthroplasty (HA), RTSA +  cemented stem, non-surgical treatment, LPF +  fibular allograft, RTSA with an inclination angle of 135° (RTSA IA 135°), RTSA. However, none of the direct or indirect comparisons resulted in statistically noticeable differences.

CONCLUSION

In conclusion, functional superiority of either treatment method is still unknown, with even high-powered RCT not being able to detect statistically noticeable differences in terms of function. Patient-individual factors, such as bone quality, sex and age have to be included when making treatment decisions.

Enhancing fixation stability in proximal humerus fractures: screw orientation optimization in PHILOS plates through finite element analysis and biomechanical testing

The optimal treatment strategy for proximal humerus fractures (PHFs) is debatable owing to the relatively high failure rate of locking plates. Optimizing implants may enhance the fixation stability of PHFs and reduce the rate of mechanical failures. We developed a finite element (FE) model to simulate the treatment of PHFs with Proximal Humerus Internal Locking System (PHILOS) plates. The model evaluated the average bone strain around the screw tips under vertical loading (as an alternative to the risk of cyclic screw cutout failure verified through biomechanical testing) to minimize this strain and maximize predicted fixation stability. After determining the optimal screw configuration, further FE analysis and in vitro biomechanical testing were conducted on both standard and optimized PHILOS screw orientation to assess whether the optimized plates have biomechanical advantages over the standard plates. The FE-based optimized configuration exhibited significantly lower bone strain around the implant than the standard PHILOS screw orientation (- 17.24%, p < 0.001). In both FE analysis and in vitro biomechanical testing, the optimized PHILOS plates achieved significantly lower average bone strain around the screws (p < 0.05), more uniform stress distribution, and greater structural stiffness (p < 0.05) than the standard PHILOS screw orientation. Our results show that biomechanical performance of the PHILOS plates can be improved by altering the orientation of the locking screws. This approach may be useful for future patient-specific design optimization of implants for other fractures.

Cement augmentation for proximal humerus fractures: a meta-analysis of randomized trials and observational studies

INTRODUCTION

It is unclear if elderly patients treated with plate osteosynthesis for proximal humerus fractures benefit from cement augmentation. This meta-analysis aims to compare cement augmentation to no augmentation regarding healing, complications, and functional results.

METHODS

PubMed, Embase, and Cochrane Central Register of Controlled Trials were searched for randomized clinical trials and observational studies. Effect estimates were pooled across studies using random effects models. The primary outcome is overall complication rate. Stratified analyses were performed for types of complication (implant-related or systemic). Secondary outcomes include re-interventions, hospital stay, operation time, functional scores, and general quality of life.

RESULTS

Five observational studies and one randomized controlled trial with a total of 541 patients were included. The overall complication rate was significantly lower in the augmented group (15.6% versus 25.4%, OR 0.54 (95%CI 0.33-0.87)). This was caused by a reduction of implant-related complications (10.4% vs. 19.9%, OR 0.49 (95%CI 0.28, 0.88)). No difference in humeral head necrosis was found. Data on re-intervention, hospital stay, and operation time was limited but did not show significant differences. No impact on functional scores and general quality of life was detected.

CONCLUSION

This meta-analysis shows that cement augmentation may reduce overall complications, mainly by preventing implant-related complications. No difference was detected regarding need for re-intervention, functional scores, general quality of life, and hospital stay. This is the first meta-analysis on this topic. It remains to be seen whether conclusions will hold when more and better-quality data becomes available.

Locking Plate Fixation with Calcium Phosphate Bone Cement Augmentation for Elderly Proximal Humerus Fractures-A Single-Center Experience and Literature Review

Proximal humerus fractures (PHFs) are among the most common upper-extremity fractures, with a rising incidence linked to the growing elderly population. Treatment options include non-surgical and surgical methods, but the best approach for geriatric PHFs remains debated. Patient selection for treatment must consider clinical and functional outcomes and the potential complications of surgery. Osteoporosis, a key factor in elderly PHFs, meaning those in patients over 65 years old, often results from low-energy trauma and necessitates treatments that enhance bone healing. Bone cement, such as calcium phosphate, is widely used to improve fracture stability and healing. However, the benefits of surgical fixation with bone cement augmentation (BCA) for elderly PHF patients remain controversial. Hence, in this article, we searched databases including MEDLINE, Embase, the Cochrane Central Register of Controlled Trials, and Web of Science to analyze the evidence on locking plate fixation (LPF) with BCA for proximal humeral fractures. We aim to provide readers with updates concerning the above issues.

Augmented versus non-augmented locking-plate fixation in proximal humeral fractures

Aims

Proximal humeral fractures are the third most common fracture among the elderly. Complications associated with fixation include screw perforation, varus collapse, and avascular necrosis of the humeral head. To address these challenges, various augmentation techniques to increase medial column support have been developed. There are currently no recent studies that definitively establish the superiority of augmented fixation over non-augmented implants in the surgical treatment of proximal humeral fractures. The aim of this systematic review and meta-analysis was to compare the outcomes of patients who underwent locking-plate fixation with cement augmentation or bone-graft augmentation versus those who underwent locking-plate fixation without augmentation for proximal humeral fractures.

Methods

The search was carried out according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. Articles involving patients with complex proximal humeral fractures treated using open reduction with locking-plate fixation, with or without augmentation, were considered. A meta-analysis of comparative studies comparing locking-plate fixation with cement augmentation or with bone-graft augmentation versus locking-plate fixation without augmentation was performed.

Results

A total of 19 studies were included in the qualitative synthesis, and six comparative studies were included in the meta-analysis. Overall, 120 patients received locking-plate fixation with bone-graft augmentation, 179 patients received locking-plate fixation with cement augmentation, and 336 patients received locking-plate fixation without augmentation. No statistically relevant differences between the augmented and non-augmented cohorts were found in terms of the Disabilities of the Arm, Shoulder and Hand questionnaire score and Constant-Murley Score. The cement-augmented group had a significantly lower rate of complications compared to the non-augmented group.

Conclusion

While locking-plate fixation with cement augmentation appears to produce a lower complication rate compared to locking-plate fixation alone, functional outcomes seem comparable between augmented and non-augmented techniques.

Poor midterm clinical outcomes and a high percentage of unsatisfying results are reported after seizure-related shoulder injuries, especially after posterior proximal humerus fracture-dislocations

BACKGROUND

Treating seizure-related shoulder injuries is challenging, and an evidence-based consensus to guide clinicians is lacking. The aim of this prospective single-center observational clinical trial was to evaluate the clinical results of a cohort of patients undergoing treatment of seizure-related shoulder injuries, to categorize them according to the lesion's characteristics, with special focus on patients with proximal humerus fracture-dislocations (PHFDs), and to define groups at risk of obtaining unsatisfactory results. We hypothesized that patients with a PHFD, considered the worst-case scenario among these injuries, would report worse clinical results in terms of the quick Disabilities of the Arm, Shoulder, and Hand questionnaire (qDASH) as compared to the other patients.

METHODS

Patients referred to a tertiary epilepsy center who have seizure-related shoulder injuries and with a minimum follow-up of 1 year were included. A quality-of-life assessment instrument (EQ-5D-5L), a district-specific patient-reported outcome measure (qDASH), and a pain assessment tool (visual analog scale [VAS]) were used for the clinical outcome evaluation. Subjective satisfaction and fear of new shoulder injuries was also documented. Categorization and subgroup analysis according to the presence and features of selected specific lesions were performed.

RESULTS

A total of 111 patients were deemed eligible and 83 were available for follow-up (median age 38 years, 30% females), accounting for a total of 107 injured shoulders. After a median follow-up of 3.9 (1.6-8.2) years, overall moderate clinical results were reported. In addition, 34.1% of the patients reported a VAS score ≥35 mm, indicating moderate to severe pain, and 34.1% a qDASH score ≥40 points, indicating severe disability of an upper limb. These percentages rose to, respectively, 45.5% and 48.5% in the subgroup of patients with PHFDs and to 68.8% and 68.8% in patients experiencing posterior PHFD. Overall, 46.9% of the patients considered themselves unsatisfied with the treatment and 62.5% reported a persistent fear of a new shoulder injury.

CONCLUSIONS

Patients with seizure-related shoulder injuries reported only moderate clinical results at their midterm follow-up. Older age, male sex, and absence or discontinuation of antiepileptic drug (AED) treatment were identified as characterizing features of patients with posterior dislocation episodes. In patients with PHFD, a tendency to worse clinical results was observed, with posterior PHFD patients emerging as a definite subgroup at risk of reporting unsatisfying results after treatment.

Assessment of therapeutic clinical trials for proximal humeral fractures

Proximal humeral fractures (PHFs) are a common injury among the older population. An ideal therapeutic protocol has yet to be developed, and numerous clinical trials are being conducted to find the best therapeutic approach. The purpose of this study is to evaluate the current body of knowledge available via interventional clinical trials. In December 2022, interventional clinical trials relating to PHFs on Clinicaltrials.gov were screened. Trial characteristics included duration, status, intervention, phase, outcomes, location, and study design. Publications associated with each trial were searched on PubMed/Medline using the ClinicalTrials.gov registry number. The final dataset comprised 64 trials. The most common trial status was completed (36%). The majority did not have a Food and Drug Administration-defined phase (67%), was randomized (81%), involved a single facility (72%), used a parallel assignment intervention model (80%), and used an open-label approach (45%). Eleven trials were associated with a publication, and the publication rate was 17%. Average enrollment was 86 participants, and mean trial duration was 51.4 months. Europe/UK/Russia/Turkey participated in the most trials (70%). Most of the trials were initiated after 2010 (87.5%). Procedure-related interventions (55%) were most common. Disability/function was the most common primary outcome assessed (61%). The low publication rate and the multitude of trials conducted after 2010 highlight the urgency and need for trial results to be published to establish an ideal therapeutic protocol. Since the majority of the trials involved a single institution and an open-label approach, reinforcing blinding and establishing multi-centered trials can improve the validity of the clinical trial results.

Cyclosporine a inhibits bone regeneration and induces bone loss in a rat model

Cyclosporine A (CSA) is an immunosuppressant that has been extensively studied for its side effects on inhibiting osseointegration of titanium implants. However, the impact of CSA on bone healing in postmenopausal osteoporosis remains unknown. Therefore, this study aimed to investigate the effect of CSA on bone repair in an ovariectomized (OVX) rat model through both in vitro and in vivo experiments. We examined the interventions of CSA on osteoblast progenitor cells MC3T3-E1 and assessed their effects on biological function using RT-qPCR, CCK-8 assay, alizarin red staining, and alkaline phosphatase staining. Furthermore, we evaluated the effects of CSA on bone regeneration and bone mass in both OVX rat models and femoral diaphysis bone defect models. The results from the CCK-8 experiment indicated a positive influence of experimental doses of CSA on osteogenic differentiation of MC3T3-E1 cells. ALP expression levels and calcified nodules were also evaluated, suggesting that CSA intervention promoted osteogenic differentiation in MC3T3-E1 cells. Additionally, specific gene expressions including OPN, Runx-2, OC, and Col1a1 were up-regulated after CSA intervention. Biomechanical parameters aligned with histological analysis as well as micro-CT scans confirmed worse bone microstructure and strength following CSA intervention. Our findings preliminarily suggest that whether it is normal or osteoporotic bones, CSA has adverse effects on bone health which are associated with elevated-bone turnover.

Cement-augmented locked plate fixation proximal humerus fractures in elderly patient: a systematic review and meta-analysis

BACKGROUND

This systemic review and meta-analysis aimed to evaluate the clinical outcomes of proximal humeral fracture in elderly patient fixation using locked plate with or without cement augmentation.

METHODS

The databases of PubMed, Embase, and Cochrane Library were searched in August 2023 for literature comparing the clinical outcomes of patients with PHFs treated with locked plate alone and locked plate augmented with cement. Data describing study design; level of evidence; inclusion criteria; demographic information; final follow-up; revision rate; implant failure rate; avascular necrosis rate; total complication rate; constant score; and disability of arm, shoulder, and hand (DASH) score were collected.

RESULTS

Eight studies (one randomized-controlled trial and seven observational studies), involving 664 patients, were identified. Compared with locked plates alone, using cement-augmented locked plates reduced the implant failure rate (odds ratio (OR) = 0.19; 95% confidence interval (CI) 0.10-0.39; P < 0.0001) and total complication rate (OR = 0.45; 95% CI 0.29-0.69; P = 0.0002) and improved DASH scores (mean difference (MD) = 2.99; 95% CI 1.00-4.98; P = 0.003). However, there was no significant difference in clinical outcomes, including revision rate, avascular necrosis rate, and constant score.

CONCLUSION

In this review and meta-analysis, fixation of the PHFs in elderly patients using locked plates with or without cement augmentation has no significant difference in revision rate, but the implant failure and total complication rates may be lesser on using the cement-augmented locked plate for fixation than on using a locked plate alone. Good results are expected for most patients treated with this technique.

TRIAL REGISTRATION

The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA)21 guidelines were followed to conduct this systematic review and meta-analysis and was registered as a protocol in PROSPERO (CRD42022318798).

Plate Fixation of Proximal Humerus Fractures: How to Get It Right and Future Directions for Improvement

PURPOSE OF REVIEW

Open reduction and internal fixation with locking plates (ORIF-LP) has been used for decades for the surgical management of proximal humerus fractures. Despite good outcomes have been widely published in the literature, unacceptably high rates of complications (up to 40%), many of them yielding poor outcomes and requiring reoperation (up to 25%), have also been reported, especially in elderly patients. Most common complications are related to implant failure, with intra-articular screw penetration as the most frequent and devastating.

RECENT FINDINGS

Advances in patient selection and surgical technique, and implementation of bone or cement augmentation, have been developed to hopefully decrease complication rates. Mayo-FJD Classification offers prognostic information that can aid in the decision-making process for proximal humeral fractures. Displaced valgus impacted fractures seem to be associated with well over a 10% rate of avascular necrosis after ORIF-LP. A principle-based and stepwise surgical technique combining anatomic reduction and a short screw configuration can provide good outcome in most patients, even the elderly, decreasing implant failures to less than 10%. Acrylic cement augmentation has the potential to further decrease implant failure rate to 1%. Reoperation rates are higher partly due to the need to remove hardware for painful subacromial conflict. However, no studies to date definitively demonstrated the superiority of ORIF-LP compared to non-operative treatment, intramedullary nailing, or reverse shoulder arthroplasty. ORIF-LP can provide good results for the surgical management of displaced proximal humerus fractures even in elderly patients provided adequate patient selection and a principle based and stepwise surgical technique, supplemented with bone graft or acrylic cement when needed. Poor outcomes and high complication and reoperation rates should be expected when these recommendations are not followed.

Quality of Life and Pain after Proximal Humeral Fractures in the Elderly: A Systematic Review

Background and Objectives: The proximal humeral fracture (PHF) is one of the most common fractures in elderly patients. A PHF might influence the quality of life (QoL) on several different levels, especially in elderly patients, but it is unclear which treatment option results in a better QoL outcome. Therefore, we aimed to systematically review the current literature for studies that have analyzed the QoL and pain of elderly patients treated either surgically or non-operatively for PHF. Materials and Methods: A comprehensive search of the literature was performed in the PubMed database from January to April 2023. Studies describing the QoL or the level of pain of patients older than 60 years with the EuroQoL-5 Dimension (EQ-5D) score or the visual analogue scale (VAS) after the treatment of PHF, either non-operatively (non-OP), with open-reduction and internal fixation using a locking plate (LPF), or with reverse total shoulder arthroplasty (RTSA) were included. Twelve studies were analyzed descriptively and the individual risk of bias was assessed using the ROB2 and ROBINS-I tools. Results: A total of 12 studies with 712 patients at baseline were included (78% female sex, mean age 75.2 years). The reported VAS scores at 12-month follow-up (FU) ranged from 0.7 to 2.5. The calculated overall mean VAS score across all studies showed a decreasing tendency for all treatments, with an increasing FU time up to 12 months after PHF. None of the studies reported any significant differences of the EQ-5D across the groups. The overall calculated EQ-5D indices showed an increasing trend after 6-8 weeks FU, but did not differ significantly between the three treatments. Conclusions: In conclusion, the current literature suggests that there are no clinically important differences between the QoL or pain in elderly patients with PHF after non-operative treatment or surgical treatment with LPF or RTSA. However, the number of studies and level of evidence is rather low and further trials are urgently needed.

Treatment Reality of Proximal Humeral Fractures in the Elderly-Trending Variants of Locking Plate Fixation in Germany

BACKGROUND

The surgical treatment of proximal humeral fractures (PHFs) with locking plate fixation (LPF) in the elderly is associated with high complication rates, especially in osteoporotic bone. Variants of LPF such as additional cerclages, double plating, bone grafting and cement augmentation can be applied. The objective of the study was to describe the extent of their actual use and how this changed over time.

METHODS

Retrospective analysis of health claims data of the Federal Association of the Local Health Insurance Funds was performed, covering all patients aged 65 years and older, who had a coded diagnosis of PHF and were treated with LPF between 2010 and 2018. Differences between treatment variants were analyzed (explorative) via chi-squared or Kruskal-Wallis tests.

RESULTS

Of the 41,216 treated patients, 32,952 (80%) were treated with LPF only, 5572 (14%) received additional screws or plates, 1983 (5%) received additional augmentations and 709 (2%) received a combination of both. During the study period, relative changes were observed as follows: -35% for LPF only, +58% for LPF with additional fracture fixation and +25% for LPF with additional augmentation. Overall, the intra-hospital complication rate was 15% with differences between the treatment variants (LPF only 15%, LPF with additional fracture fixation 14%, LPF with additional augmentation 19%; p < 0.001), and a 30-day mortality of 2%.

CONCLUSIONS

Within an overall decrease of LPF by approximately one-third, there is both an absolute and relative increase of treatment variants. Collectively, they account for 20% of all coded LPFs, which might indicate more personalized treatment pathways. The leading variant was additional fracture fixation using cerclages.

Continuous Shoulder Activity Tracking after Open Reduction and Internal Fixation of Proximal Humerus Fractures

Postoperative shoulder activity after proximal humerus fracture treatment could influence the outcomes of osteosynthesis and may depend on the rehabilitation protocol. This multi-centric prospective study aimed at evaluating the feasibility of continuous shoulder activity monitoring over the first six postoperative weeks, investigating potential differences between two different rehabilitation protocols. Shoulder activity was assessed with pairs of accelerometer-based trackers during the first six postoperative weeks in thirteen elderly patients having a complex proximal humerus fracture treated with a locking plate. Shoulder angles and elevation events were evaluated over time and compared between the two centers utilizing different standard rehabilitation protocols. The overall mean shoulder angle ranged from 11° to 23°, and the number of daily elevation events was between 547 and 5756. Average angles showed longitudinal change <5° over 31 ± 10 days. The number of events increased by 300% on average. Results of the two clinics exhibited no characteristic differences for shoulder angle, but the number of events increased only for the site utilizing immediate mobilization. In addition to considerable inter-patient variation, not the mean shoulder angle but the number of elevations events increased markedly over time. Differences between the two sites in number of daily events may be associated with the different rehabilitation protocols.

Traumatic brain injuries are ignored or discriminated in prospective clinical trials on shoulder fractures: a systematic review

PURPOSE

Current literature suggests a significant epidemiological association between traumatic brain injury (TBI) and proximal upper limb fractures in addition to major clinical consequences. A systematic review was conducted to assess how TBI is taken into consideration in interventional studies on shoulder fractures.

METHODS

The following data sources were used: MEDLINE, EMBASE, EBM Reviews, CINAHL, and OpenGrey databases. Study selection included interventional randomized clinical trials and prospective cohort studies on shoulder fractures published in English or French between 2008 and 2020. Studies on pathologic fractures, chronic fracture complications, nonhuman subjects, and biomechanics were excluded. Articles were reviewed by two independent authors according to the PRISMA guidelines. Baseline characteristics, exclusion criteria, and input relevant to TBI were recorded. Methodological quality was assessed with the Cochrane risk of bias tool for randomized clinical trials and the Newcastle-Ottawa Scale for cohort studies.

RESULTS

One-hundred-thirteen studies met the inclusion criteria. None discussed the possible impact of TBI on their results. Only three (2.7%) studies considered TBI relevant and included these patients in their cohort. Furthermore, 43/113 (38.1%) excluded patients with injuries or mechanisms strongly related to traumatic brain injuries: head injuries (4); moderate and/or severe TBI (7); high energy traumas (3); Polytrauma subjects (33).

CONCLUSION

TBI are ignored or discriminated in prospective clinical trials on shoulder fractures. The exclusion of these cases impacts generalizability as their prevalence is significant. Considering the major impact of TBI on important outcomes, its presence should always be assessed to ensure high quality evidence.

LEVEL OF EVIDENCE

Systematic Review, Therapeutic Level II.

Locking Plates With Computationally Enhanced Screw Trajectories Provide Superior Biomechanical Fixation Stability of Complex Proximal Humerus Fractures

Joint-preserving surgical treatment of complex unstable proximal humerus fractures remains challenging, with high failure rates even following state-of-the-art locked plating. Enhancement of implants could help improve outcomes. By overcoming limitations of conventional biomechanical testing, finite element (FE) analysis enables design optimization but requires stringent validation. This study aimed to computationally enhance the design of an existing locking plate to provide superior fixation stability and evaluate the benefit experimentally in a matched-pair fashion. Further aims were the evaluation of instrumentation accuracy and its potential influence on the specimen-specific predictive ability of FE. Screw trajectories of an existing commercial plate were adjusted to reduce the predicted cyclic cut-out failure risk and define the enhanced (EH) implant design based on results of a previous parametric FE study using 19 left proximal humerus models (Set A). Superiority of EH versus the original (OG) design was tested using nine pairs of human proximal humeri (N = 18, Set B). Specimen-specific CT-based virtual preoperative planning defined osteotomies replicating a complex 3-part fracture and fixation with a locking plate using six screws. Bone specimens were prepared, osteotomized and instrumented according to the preoperative plan via a standardized procedure utilizing 3D-printed guides. Cut-out failure of OG and EH implant designs was compared in paired groups with both FE analysis and cyclic biomechanical testing. The computationally enhanced implant configuration achieved significantly more cycles to cut-out failure compared to the standard OG design (p &lt; 0.01), confirming the significantly lower peri-implant bone strain predicted by FE for the EH versus OG groups (p &lt; 0.001). The magnitude of instrumentation inaccuracies was small but had a significant effect on the predicted failure risk (p &lt; 0.01). The sample-specific FE predictions strongly correlated with the experimental results (R2 = 0.70) when incorporating instrumentation inaccuracies. These findings demonstrate the power and validity of FE simulations in improving implant designs towards superior fixation stability of proximal humerus fractures. Computational optimization could be performed involving further implant features and help decrease failure rates. The results underline the importance of accurate surgical execution of implant fixations and the need for high consistency in validation studies.

Interventions for treating proximal humeral fractures in adults

BACKGROUND

Fractures of the proximal humerus, often termed shoulder fractures, are common injuries, especially in older people. The management of these fractures varies widely, including in the use of surgery. This is an update of a Cochrane Review first published in 2001 and last updated in 2015.

OBJECTIVES

To assess the effects (benefits and harms) of treatment and rehabilitation interventions for proximal humeral fractures in adults.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, trial registries, and bibliographies of trial reports and systematic reviews to September 2020. We updated this search in November 2021, but have not yet incorporated these results.

SELECTION CRITERIA

We included randomised and quasi-randomised controlled trials that compared non-pharmacological interventions for treating acute proximal humeral fractures in adults.  DATA COLLECTION AND ANALYSIS: Pairs of review authors independently selected studies, assessed risk of bias and extracted data. We pooled data where appropriate and used GRADE for assessing the certainty of evidence for each outcome. We prepared a brief economic commentary for one comparison.

MAIN RESULTS

We included 47 trials (3179 participants, mostly women and mainly aged 60 years or over) that tested one of 26 comparisons. Six comparisons were tested by 2 to 10 trials, the others by small single-centre trials only. Twelve studies evaluated non-surgical treatments, 10 compared surgical with non-surgical treatments, 23 compared two methods of surgery, and two tested timing of mobilisation after surgery. Most trials were at high risk of bias, due mainly to lack of blinding. We summarise the findings for four key comparisons below. Early (usually one week post injury) versus delayed (after three or more weeks) mobilisation for non-surgically-treated fractures Five trials (350 participants) made this comparison; however, the available data are very limited. Due to very low-certainty evidence from single trials, we are uncertain of the findings of better shoulder function at one year in the early mobilisation group, or the findings of little or no between-group difference in function at 3 or 24 months. Likewise, there is very low-certainty evidence of no important between-group difference in quality of life at one year. There was one reported death and five serious shoulder complications (1.9% of 259 participants), spread between the two groups, that would have required substantive treatment. Surgical versus non-surgical treatment Ten trials (717 participants) evaluated surgical intervention for displaced fractures (66% were three- or four-part fractures). There is high-certainty evidence of no clinically important difference between surgical and non-surgical treatment in patient-reported shoulder function at one year (standardised mean difference (SMD) 0.10, 95% confidence interval (CI) -0.07 to 0.27; 7 studies, 552 participants) and two years (SMD 0.06, 95% CI -0.13 to 0.25; 5 studies, 423 participants). There is moderate-certainty evidence of no clinically important between-group difference in patient-reported shoulder function at six months (SMD 0.17, 95% CI -0.04 to 0.38; 3 studies, 347 participants). There is high-certainty evidence of no clinically important between-group difference in quality of life at one year (EQ-5D (0: dead to 1: best quality): mean difference (MD) 0.01, 95% CI -0.02 to 0.04; 6 studies, 502 participants). There is low-certainty evidence of little between-group difference in mortality: one of the 31 deaths was explicitly linked with surgery (risk ratio (RR) 1.35, 95% CI 0.70 to 2.62; 8 studies, 646 participants). There is low-certainty evidence of a higher risk of additional surgery in the surgery group (RR 2.06, 95% CI 1.21 to 3.51; 9 studies, 667 participants). Based on an illustrative risk of 35 subsequent operations per 1000 non-surgically-treated patients, this indicates an extra 38 subsequent operations per 1000 surgically-treated patients (95% CI 8 to 94 more). Although there was low-certainty evidence of a higher overall risk of adverse events after surgery, the 95% CI also includes a slightly increased risk of adverse events after non-surgical treatment (RR 1.46, 95% CI 0.92 to 2.31; 3 studies, 391 participants). Open reduction and internal fixation with a locking plate versus a locking intramedullary nail Four trials (270 participants) evaluated surgical intervention for displaced fractures (63% were two-part fractures). There is low-certainty evidence of no clinically important between-group difference in shoulder function at one year (SMD 0.15, 95% CI -0.12 to 0.41; 4 studies, 227 participants), six months (Disability of the Arm, Shoulder, and Hand questionnaire (0 to 100: worst disability): MD -0.39, 95% CI -4.14 to 3.36; 3 studies, 174 participants), or two years (American Shoulder and Elbow Surgeons score (ASES) (0 to 100: best outcome): MD 3.06, 95% CI -0.05 to 6.17; 2 studies, 101 participants). There is very low-certainty evidence of no between-group difference in quality of life (1 study), and of little difference in adverse events (4 studies, 250 participants) and additional surgery (3 studies, 193 participants). Reverse total shoulder arthroplasty (RTSA) versus hemiarthroplasty There is very low-certainty evidence from two trials (161 participants with either three- or four-part fractures) of no or minimal between-group differences in self-reported shoulder function at one year (1 study) or at two to three years' follow-up (2 studies); or in quality of life at one year or at two or more years' follow-up (1 study). Function at six months was not reported. Of 10 deaths reported by one trial (99 participants), one appeared to be surgery-related. There is very low-certainty evidence of a lower risk of complications after RTSA (2 studies). Ten people (6.2% of 161 participants) had a reoperation; all eight cases in the hemiarthroplasty group received a RTSA (very low-certainty evidence).

AUTHORS' CONCLUSIONS

There is high- or moderate-certainty evidence that, compared with non-surgical treatment, surgery does not result in a better outcome at one and two years after injury for people with displaced proximal humeral fractures. It may increase the need for subsequent surgery. The evidence is absent or insufficient for people aged under 60 years, high-energy trauma, two-part tuberosity fractures or less common fractures, such as fracture dislocations and articular surface fractures. There is insufficient evidence from randomised trials to inform the choices between different non-surgical, surgical or rehabilitation interventions for these fractures.

[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.

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.

Age-Independent Clinical Outcome in Proximal Humeral Fractures: 2-Year Results Using the Example of a Precontoured Locking Plate

INTRODUCTION

The optimal treatment strategy for the proximal humeral fracture (PHF) remains controversial. The debate is centered around the correct treatment strategy in the elderly patient population. The present study investigated whether age predicts the functional outcome of locking plate osteosynthesis for this fracture entity.

METHODS

A consecutive series of patients with surgically treated displaced PHF between 01/2017 and 01/2018 was retrospectively analyzed. Patients were treated by locking plate osteosynthesis. The cohort was divided into two groups: Group 1 (≥65 years) and Group 2 (<65 years). At the follow-up examination, the SSV, CMS, ASES, and Oxford Shoulder Score (OS), as well as a radiological follow-up, was obtained. The quality of fracture reduction is evaluated according to Schnetzke et al. Results: Of the 95 patients, 79 were followed up (83.1%). Group 1 consists of 42 patients (age range: 65-89 years, FU: 25 months) and Group 2 of 37 patients (28-64 years, FU: 24 months). The clinical results showed no significant differences between both groups: SSV 73.4 ± 23.4% (Group 1) vs. 80.5 ± 189% (Group 2). CMS: 79.4 ± 21 vs. 81.9 ± 16, ASES: 77.2 ± 20.4 vs. 77.5 ± 23.1, OS: 39.5 ± 9.1 vs. 40.8 ± 8.2; OS: 39.5 ± 9.1 vs. 40.8 ± 8.2. In the radiological follow-up, fractures healed in all cases. Furthermore, the quality of fracture reduction in both groups is comparable without significant differences. The revision rate was 9.5% in Group 1 vs. 16.2% in Group 2.

DISCUSSION

Both age groups show comparable functional outcomes and complication rates. Thus, the locking plate osteosynthesis can be used irrespective of patient age; the treatment decision should instead be based on fracture morphology and individual patient factors.

Primary stability of cement augmentation in locking plate fixation for proximal humeral fractures: A comparison of absorbable versus non-absorbable cement

BACKGROUND

Cement augmentation has been suggested to increase the stability of screw anchoring in osteoporotic humeral fractures. Initial results are promising but may be jeopardized by cement leakage into the joint and difficult implant removal. Absorbable cement might have advantages in this regard, but it is unclear if the primary stability of both techniques is equivalent to each other. Therefore, this study aimed to compare its primary stability with that of non-absorbable cement augmentation.

METHODS

Nineteen cadaveric humeri with two-part fracture models were treated with locking plate osteosynthesis and cement augmentation using either absorbable calcium phosphate cement (group 1) or polymethylmethacrylate (group 2). Fracture movement, stiffness, failure mode, and ultimate load under cyclic compressive loading were examined and compared between the groups.

FINDINGS

The absolute and relative stiffness values in group 1 were significantly smaller than those in group 2 after 50 cycles (group 1: 114 ± 38 N/mm and 94 ± 8% vs. group 2: 188 ± 71 N/mm and 106 ± 9%; p₅₀ = 0.022), 2000 cycles (group 1: 97 ± 34 N/mm and 81 ± 15% vs. group 2: 153 ± 47 N/mm and 88 ± 15%; p₂₀₀₀ = 0.028), and 5000 cycles (group 1: 98 ± 40 N/mm and 81 ± 22% vs. group 2: 158 ± 40 N/mm and 92 ± 16%; p₅₀₀₀ = 0.028). The failure load was not statistically significantly different between the groups.

INTERPRETATION

Although the PMAA group showed higher values for absolute and relative stiffness, no statistically significant difference was found in the primary stability between absorbable and non-absorbable cement augmentation supporting plate osteosynthesis in proximal humeral fractures. In view of the potential advantages of bio-absorbable cement during the healing process, its use should be considered for the augmentation and stabilization of osteoporotic fractures.

Angle-stable polyaxial locked plating with and without polymethylmethacrylate cement augmentation for proximal humeral fractures in elderly

Objectives

This study aims to evaluate the outcomes of proximal humeral fracture (PHF) fixation with a polyaxial locking plate (PLP) osteosynthesis alone versus cement-augmented PLP (PLP-CA) in an elderly population.

Patients and methods

Between May 2015 and June 2018, a total of 101 patients (17 males, 84 females; mean age: 74.5±8.1 years; range, 60 to 94 years) aged ≥60 years with an acute PHF who underwent osteosynthesis with PLP or PLP-CA were retrospectively analyzed. The patients were divided into two groups as the PLP (n=53) and PLP-CA (n=48). Clinical outcomes, Constant-Murley Scores (CMS), Disabilities of the Arm, Shoulder and Hand (DASH) scores, and Short Form-12 (SF-12) scores were compared between the groups.

Results

The overall mean follow-up was 28.1±11.1 months. No clinically relevant differences in the mean duration of surgery, mean intraoperative X-ray image intensifier time or postoperative in-hospital stay were found between the groups. A higher complication rate was observed in the PLP group (20.8% in PLP vs. 10.4% in PLP-CA; p<0.05). There was no statistically significant difference for this (t-test, p=0.08848). The CMS for the operated side did not show any significant differences between the groups. Also, no statically significant difference was seen in the SF-12. A slightly improved DASH score was found for the PLP group (p=0.02908).

Conclusion

During follow-up PLP-CA osteosynthesis yielded nearly similar functional outcomes to PLP fracture fixation, despite with an overall lower rate of complication regarding secondary loss of reduction and screw cut-out. The polymethylmethacrylate cement augmentation can decrease morbidity in this patient group.

Proximal humeral fracture locking plate fixation with anatomic reduction, and a short-and-cemented-screws configuration, dramatically reduces the implant related failure rate in elderly patients

Background

Multiple studies have reported an unacceptable implant-related complication rate in proximal humeral fractures treated with locking plates, particularly in older patients. Our objective was to compare the fracture fixation failure rates in elderly patients, after a dedicated technique for locking plate fixation with cement augmentation or without it.

Methods

A total of 168 open reduction and internal fixation with locking plates were performed for complex proximal humerus fractures by a single surgeon in 136 women and 32 men older than 65 years of age (average 76 years). Treatment groups included group 1 with noncemented screws (n = 90) and group 2 with cemented screws (n = 78). As per Mayo-FJD Classification, there were 74 (44%) varus posteromedial impaction, 41 (24%) algus impaction, 46 (28%) surgical neck, and 7 (4%) head dislocation injuries. A retrospective radiographic and a clinical analysis was performed.

Results

At a mean follow-up of 33 months, the implant failure rate was significantly lower in the cement augmentation group (1% vs. 8%, P = .03). The overall complication rate was 21% (25% group 1, 15% group 2; P = .1). Global avascular necrosis was associated with sustaining a valgus impacted fracture (P = .02 odds ratio 5.7), but not to augmentation. Partial avascular necrosis occurred only in patients treated with cemented screws (3.8%). The overall revision rate was 9% in both groups. Forward elevation was 126 ± 36 degrees and external rotation was 44 ± 19 degrees. The mean Constant score was 70 ± 15 in group 1 and 76 ± 15 in group 2 (P = .03).

Conclusion

Cement augmentation significantly decreased the rate of implant failure. Good results are expected for most patients treated with this technique.

Screw-Tip Augmented Locked Plating Versus Primary Reverse Total Shoulder Arthroplasty in Displaced Proximal Humeral Fractures: A Retrospective Comparative Cohort Study With a Mean Follow-Up of 39 Months

Introduction

This study compared the clinical and radiologic outcomes of screw-tip augmented locking plate osteosynthesis (STA) vs primary reverse total shoulder arthroplasty (RSA) in elderly patients with displaced proximal humeral fractures.

Methods

60 patients (age >65 years) with a displaced proximal humeral fracture underwent open reduction and internal fixation with locking plate and fluoroscopy controlled screw-tip augmentation. Sixty matched individuals (age, gender, fracture pattern, and mean follow-up) treated by RSA for fractures were identified from the institutional database and outcomes as well as occurring complications and need for revision surgery were compared.

Results

At 39 months’ follow-up, 25 patients in the STA group (mean age 74.5 ± 12 years, 76.7% woman) showed a mean Constant Score (CS) of 68 ± 18.8 points. Mean %CS compared to the contralateral side was 81.6 ± 19.8%. Of 60 matched individuals in the RSA group, 22 patients (mean age 78.9 ± 8.2 years, 76.7% woman) showed a mean CS of 60.6 ± 21.2 points (P = .33), and the mean %CS compared to the contralateral side was 81.6 (74.7 ± 18.6)% (P = .14). The overall complication rate in STA group was 32% (secondary varus or valgus displacement >10°, n = 4, avascular necrosis, n = 4). In RSA group, the overall complication rate was 4.5% (P = <.05). We observed one early onset infection. Revision surgery with removal of the prosthesis and PMMA spacer implantation for two-stage revision was necessary. The follow-up rate was 41.7 vs 36.7%.

Conclusions

Screw-tip augmented locked plating and reverse total shoulder arthroplasty result in comparable satisfying functional outcome 3 years following a displaced proximal humeral fracture in elderly patients. However, we noted a higher complication and revision rate in the STA group. In contrast, primary reversed shoulder arthroplasty resulted in a lower rate of complications and revisions, which may be beneficial in elderly patients.

DOES CEMENT CURING CAUSE CONCERNING INCREASE OF THE TEMPERATURE WHEN DELIVERED IN THE HUMAN HUMERUS?

For the treatment of humeral fractures, numerous strategies exist to improve the clinical outcome of the reconstruction and to reduce the incidence of fixation failure. Injection of acrylic-based cements to reinforce the bone and/or augment the screws is one option. The heat generated during cement polymerization raises some concerns, as it could cause tissue damage. The first aim of this study was to measure the temperature over time during polymerization when acrylic cements are delivered inside the bone to treat fracture. The second aim was to assess if the ISO-5833:2002 standard can predict what happens in a real bone. Different tests were performed using two acrylic-based cements (Mendec and Cal-Cemex): (i) the ISO-5833:2002 standard (Annex C); (ii) tests on human bones (humeral diaphysis and humeral head) injected with cement to simulate fracture treatment. In the humeri, the highest temperature was measured in the diaphysis (68.6∘C for Mendec, 62.7∘C for Cal-Cemex). These values are comparable with the temperature reached in other consolidated applications (vertebroplasty). Exposure to high temperature was shorter for the diaphysis than for the head. For both cements, in both the diaphysis and the head, temperatures exceeded 48∘C for less than 10[Formula: see text]min. This is within the threshold for tissue necrosis. The ISO-5833:2002 yielded significantly different results in terms of maximum temperature (difference exceeding 15∘C) and exposure to temperature above 48∘C and 45∘C. This discrepancy is probably due to a combination of factors affecting the amount of heat produced and dissipated (e.g., amount and shape of the cement, thermal conductivity).

The fragility and reverse fragility indices of proximal humerus fracture randomized controlled trials: a systematic review

BACKGROUND

The quality of evidence of the orthopedic literature has been often called into question. The fragility index (FI) has emerged as a means to evaluate the robustness of a significant result. Similarly, reverse fragility index (RFI) can be used for nonsignificant results to evaluate whether one can confidently conclude that there is no difference between groups. The analysis of FI and RFI in proximal humerus fracture (PHF) management is of particular interest, given ongoing controversy regarding optimal management and patient selection. The aim of this study was to report the FI, RFI and quality of the evidence in the proximal humerus fracture literature.

METHODS

A systematic review was conducted based on the PRISMA (preferred reporting items for systematic reviews and meta-analyses) guidelines, which utilized EMBASE, MEDLINE and Cochrane Library databases. Inclusion criteria included randomized controlled clinical trials related to the management of proximal humerus fractures, published from 2000 to 2020 with dichotomous outcome measures and 1:1 allocation. The FI and RFI were calculated by successively changing one nonevent to an event for each outcome measure until the result was made nonsignificant or significant, respectively. The fragility quotient, (FQ), calculated by dividing the FI by the total sample size, was calculated as well.

RESULTS

There were 25 studies that met our criteria with 48 outcome measures recorded. A total of 21 studies had at least one fragile result, with ten studies including a fragile result in the conclusion of the abstract. A total of 31 outcome measures had nonsignificant results and the median RFI was found to be 4, with 71% greater than number of patients lost to follow up. Seventeen outcomes had significant results, with a median FI of 1, with 65% greater than or equal to the number patients lost to follow up. A total of 18 of 25 studies (72%) included a power analysis. In particular, ten studies reported a statistical analysis of complication rates, 90% of which were fragile. The median FQ was found to be 0.037.

CONCLUSIONS

The literature on PHF management is frequently fragile. Outcome measures are often fragile, particularly with regards to comparing complication rates and reoperation rates in treatment arms. Comparing to the studies in other subspecialties PHF RCTs are relatively more fragile and underpowered. Standardized reporting of FI, FQ and RFI can help the reader to reliably draw conclusions based on the fragility of outcome measures.

Latest Trends in the Current Treatment of Proximal Humeral Fractures - an Analysis of 1162 Cases at a Level-1 Trauma Centre with a Special Focus on Shoulder Surgery

BACKGROUND

The management of proximal humeral fracture (PHF) is not only complex but ever changing. Published epidemiological data are often dated and do not factor in demographic changes or the latest developments in implant material and surgical techniques.

AIMS

The primary aim of this study was to evaluate changes in the epidemiology and actual treatment of PHF at a level-1 trauma centre, with a special focus on shoulder surgery.

HYPOTHESES

1. Between 2009 to 2012 and 2014 to 2017, an increase in complex PHF entities can be observed. 2. In correlation with fracture complexity, an increasing number of comorbidities, especially osteoporosis, can be observed.

METHODS

Between 2014 and 2017, a total of 589 patients (73% female; mean age: 68.96 ± 14.9 years) with 593 PHFs were treated. Patient records and imaging (XRs and CTs) of all patients were analysed. Fractures with ad latus displacement of a maximum of 0,5 cm and/or humeral head angulation of less than 20° were classified as non-displaced. Patients with displaced fractures were included in the analysis of the therapeutic algorithm. These results were compared to those of a cohort 2009 to 2012 (566 patients, 569 PHFs), which used the same inclusion criteria.

RESULTS

The two cohorts showed comparable patient numbers, as well as gender and age distributions. Between 2009 to 2012 and 2014 to 2017, a decrease in 2-part fractures (13.9 to 8.6%) and a simultaneous increase in 4-part fractures (20.4 to 30%), and thus fracture complexity was observed. Further decreases were observed in conservative therapy (27.8 to 20.6%), nail osteosynthesis (10.7 to 2.7%) and anatomic shoulder arthroplasty (5,4 to 1%). Furthermore, there was an increase in the use of locking plate osteosynthesis (43.2 to 56.7%) and reverse shoulder arthroplasty (9 to 18.4%). The general trend shows an increase in surgical therapy between the years (72.2 to 79.4%), as well as an increase in osteoporosis incidence (13 to 20.6%). The greatest numbers of comorbidities were found in 3- and 4-part fractures.

CONCLUSION

There is an increase in both the complexity of fractures and the number of surgically treated fractures between 2009 and 2012. Furthermore, an increase in osteoporosis numbers can be observed. New implants (PEEK, fenestrated screws for cement augmentation) and new surgical techniques (double plating osteosynthesis) were used as a result of increasing fracture complexity. Moreover, reverse total shoulder arthroplasty was used more commonly.

Experimental and numerical investigation of secondary screw perforation in the human proximal humerus

Surgical treatment of proximal humerus fractures remains challenging, with a reported failure rate ranging from 15% to 35%. The dominant failure mode is secondary, i.e. post-operative screw perforation through the glenohumeral joint. A better understanding and the ability to predict this complication could lead to improved fracture fixation and decreased failure rate. The aims of this study were (1) to develop an experimental model for single screw perforation in the human humeral head and (2) to evaluate the ability of densitometric measures and micro finite element (microFE) analyses to predict the experimental failure event. Screw perforation was investigated experimentally in twenty cuboidal specimens cut from four pairs of fresh-frozen human cadaveric proximal humeral heads. A centrally inserted 3.5 mm screw was pushed quasi-statically at a constant displacement rate until perforation of the articular cartilage in each specimen. Force and displacement were recorded and evaluated at both initial screw loosening and perforation events. Bone volume was calculated around and in front of the screw and tip-to-joint distance was measured on the combined pre- and post-instrumentation micro computed tomography (microCT) scans. Implicit linear and explicit non-linear microFE models were created based on the microCT scans. The strength of these densitometric, geometrical and microFE methods to predict the experimental results was evaluated via correlation analysis. The bone volume measures were optimized in a parametric analysis to maximize correlation coefficients. The strongest and quantitatively correct predictions of perforation force (R² = 0.93) and displacement (R² = 0.77) were achieved using the explicit, non-linear microFE models. Linear microFE simulations provided the strongest predictions of loosening force (R² = 0.90). Correlation strengths reached by optimized bone volume measures for predicting experimental force and by tip-to-joint distance for predicting displacement were only slightly inferior compared to the results of microFE models. The strong correlations achieved with densitometric and geometric measures indicate that monotonic perforation of single screws through the articular surface of the humeral head can be well predicted with these easily accessible measures. However, non-linear microFE models delivered even stronger correlations and quantitatively correct predictions of perforation force and displacement. This indicates that if computational resources are available, non-linear simulations may have a high potential to investigate more complex fixations and loading scenarios.

Reconstruction of proximal humeral fractures without screws using a reinforced bone substitute

Multi-fragment fractures are still a challenge: current clinical practice relies on plates and screws. Treatment of fractures of the proximal humerus has the intra-operative risk of articular damage when inserting multiple screws. Distal-varus collapse of the head is a frequent complication in osteoporotic patients. The aim of this biomechanical study was to investigate if an Innovative-cement-technique (the screws are replaced by injection of cement) provides the same or better stability of the reconstructed head compared to the Standard-technique (locking screws). A four-fragment fracture was simulated in twelve pairs of humeri, with removal of part of the cancellous bone to simulate osteoporotic "eggshell" defect. One humerus of each pair was repaired either with a Standard-technique (locking plate, 2 cortical and 6 locking screws), or with the Innovative-cement-technique (injection of a partially-resorbable reinforced bone substitute consisting of PMMA additivated with 26% beta-TCP). Cement injection was performed both in the lab and under fluoroscopic monitoring. The reconstructed specimens were tested to failure with a cyclic force of increasing amplitude. The Innovative-cement-technique withstood a force 3.57 times larger than the contralateral Standard reconstructions before failure started. The maximum force before final collapse for the Innovative-cement-technique was 3.56 times larger than the contralateral Standard-technique. These differences were statistically significant. The Innovative-cement-technique, based on the reinforced bone substitute, demonstrated better biomechanical properties compared to the Standard-technique. These findings, along with the advantage of avoiding the possible complications associated with the locking screws, may help safer and more effective treatment in case of osteoporotic multi-fragment humeral fractures.

Cement augmentation of calcar screws may provide the greatest reduction in predicted screw cut-out risk for proximal humerus plating based on validated parametric computational modelling: Augmenting proximal humerus fracture plating

Aims

Fixation of osteoporotic proximal humerus fractures remains challenging even with state-of-the-art locking plates. Despite the demonstrated biomechanical benefit of screw tip augmentation with bone cement, the clinical findings have remained unclear, potentially as the optimal augmentation combinations are unknown. The aim of this study was to systematically evaluate the biomechanical benefits of the augmentation options in a humeral locking plate using finite element analysis (FEA).

Methods

A total of 64 cement augmentation configurations were analyzed using six screws of a locking plate to virtually fix unstable three-part fractures in 24 low-density proximal humerus models under three physiological loading cases (4,608 simulations). The biomechanical benefit of augmentation was evaluated through an established FEA methodology using the average peri-screw bone strain as a validated predictor of cyclic cut-out failure.

Results

The biomechanical benefit was already significant with a single cemented screw and increased with the number of augmented screws, but the configuration was highly influential. The best two-screw (mean 23%, SD 3% reduction) and the worst four-screw (mean 22%, SD 5%) combinations performed similarly. The largest benefits were achieved with augmenting screws purchasing into the calcar and having posteriorly located tips. Local bone mineral density was not directly related to the improvement.

Conclusion

The number and configuration of cemented screws strongly determined how augmentation can alleviate the predicted risk of cut-out failure. Screws purchasing in the calcar and posterior humeral head regions may be prioritized. Although requiring clinical corroborations, these findings may explain the controversial results of previous clinical studies not controlling the choices of screw augmentation.

Does the magnitude of injuries affect the outcome of proximal humerus fractures treated by locked plating (PHILOS)?

PURPOSE

Health-related quality of life (HRQoL) becomes increasingly relevant in an aging society. Functional outcome (FO) and the patient-reported outcome (PRO) after surgical treatment of proximal humerus fractures (PHF) depends on numerous factors, including patient- and injury-specific factors. There is little evidence on how the FO and the PRO vary in different settings such as monotrauma or multiple injuries, even though the PHF is one of the more frequent fractures. In addition, to a previous study, on multiple injured patients and upper extremity injuries, the aim of the current study was to investigate the impact of multiple injuries, quantified by the ISS, on the FO and PRO after surgically treated PHF by PHILOS.

METHODS

A retrospective cohort-study was conducted with an additional follow-up by a questionnaire. HRQoL tools such as range of motion (ROM), the Quick-Disability of Arm Shoulder and Hand score (DASH), EuroQol Five Dimension Three Levels (EQ-5D-3L), and EuroQol VAS (EQ-VAS) were used. The study-population was stratified according to ISS obtained based on information at discharge into Group I/M-H (ISS < 16 points) and Group PT-H (ISS ≥ 16). Median outcome scores were calculated and presented.

INCLUSION CRITERIA

adult patients (> 18 years) with PHF treated at one academic Level 1 trauma center between 2007 and 2017 with Proximal Humeral Inter-Locking System (PHILOS) and preoperative CT-scan. Group stratification according Injury Severity Score (ISS): Group PT-H (ISS ≥ 16 points) and Group I/M-H (ISS < 16 points).

EXCLUSION CRITERIA

oncology patients, genetic disorders affecting the musculoskeletal system, paralysis or inability to move upper extremity prior or after injury, additional ipsilateral upper limb fractures, open injuries, associated vascular injuries as well brachial plexus injuries and nerve damages. Follow-up 5-10 years including PRO: EQ-5D-3L and EQ-VAS. FO, including DASH and ROM. The ROM was measured 1 year after PHILOS.

RESULTS

Inclusion of 75 patients, mean age at injury was 49.9 (± 17.6) years. The average follow-up period in Group I/M-H was 6.18 years (± 3.5), and in Group PT-H 5.58 years (± 3.1). The ISS in the Group I/M-H was 6.89 (± 2.5) points, compared to 21.7 (± 5.3) points in Group PT-H (p ≤ 0.001). The DASH-score in Group I/M-H was 9.86 (± 13.12 and in Group PT-H 12.43 (± 15.51, n.s.). The EQ-VAS in Group I/M-H was 78.13 (± 19.77) points compared with 74.13 (± 19.43, n.s.) in Group PT-H. DASH, EQ-VAS as well as ROM were comparable in Groups I/M-H and PT-H (9.9 ± 13.1 versus 12.4 ± 15.5, n.s.). The EQ-5D-3L in Group I/M-H was 0.86 (± 0.23) points compared to Group PT-H 0.72 (± 0.26, p ≤ 0.017). No significant differences could be found in Group I/M-H and PT-H in the severity of traumatic brain injury (TBI). A multivariable regression analyses was performed for DASH, EQ-5D-3L and EQ-VAS. All three outcome metrics were correlated. There was a significant difference between the EQ-5D-3L and the ISS (Beta-Coefficient was 0.86, 95% low was 0.75, 95% high was 0.99, p ≤ 0.041). No significant correlation could be found comparing DASH, EQ-5D-3L and EQ-VAS to age, gender and TBIs.

CONCLUSION

Multiple injuries did not affect the DASH, ROM or EQ-VAS after PHILOS; but a higher ISS negatively affected the EQ-5D-EL. While the ROM and DASH aim to be objective measurements of functionality, EQ-5D-3L and EQ-VAS represent the patients' PRO. The FO and PRO outcomes are not substitutable, and both should be taken into consideration during follow-up visits of multiple injured patients. Future research should prospectively explore whether the findings of this study can be recreated using a larger study population and investigate if different FO and PRO parameters come to similar conclusions. The gained information could be used for an enhanced long-term evaluation of patients who suffered a PHF from multiple injuries to meet their multifarious conditions.

LEVEL OF EVIDENCE

II.

Synthetic Bone Substitutes and Mechanical Devices for the Augmentation of Osteoporotic Proximal Humeral Fractures: A Systematic Review of Clinical Studies

BACKGROUND

Different augmentation techniques have been described in the literature in addition to the surgical treatment of proximal humeral fractures. The aim of this systematic review was to analyze the use of cements, bone substitutes, and other devices for the augmentation of proximal humeral fractures.

METHODS

A systematic review was conducted by using PubMed/MEDLINE, ISI Web of Knowledge, Cochrane Library, Scopus/EMBASE, and Google Scholar databases according the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines over the years 1966 to 2019. The search term "humeral fracture proximal" was combined with "augmentation"; "polymethylmethacrylate, PMMA"; "cement"; "bone substitutes"; "hydroxyapatite"; "calcium phosphates"; "calcium sulfate"; "cell therapies", and "tissue engineering" to find the literature relevant to the topic under review.

RESULTS

A total of 10 clinical studies considered eligible for the review, with a total of 308 patients, were included. Mean age at the time of injury was 68.8 years (range of 58-92). The most commonly described techniques were reinforcing the screw-bone interface with bone PMMA cement (three studies), filling the metaphyseal void with synthetic bone substitutes (five studies), and enhancing structural support with metallic devices (two studies).

CONCLUSION

PMMA cementation could improve screw-tip fixation. Calcium phosphate and calcium sulfate injectable composites provided good biocompatibility, osteoconductivity, and lower mechanical failure rate when compared to non-augmented fractures. Mechanical devices currently have a limited role. However, the available evidence is provided mainly by level III to IV studies, and none of the proposed techniques have been sufficiently studied.

Does cement augmentation of the screws in angular stable plating for proximal humerus fractures influence the radiological outcome: a retrospective assessment

BACKGROUND

Screw-tip augmentation in angular stable plating offers new possibilities for the treatment of complex proximal humerus fractures. This retrospective analysis was performed to evaluate the radiological outcome of proximal humerus fractures treated with angular stable plates and additional screw-tip cement augmentation in patients over the age of 60.

MATERIALS AND METHODS

A retrospective single centre analysis was conducted from June 2013 to December 2016. The minimum follow-up time was set to 6 months after surgery. Anatomical reduction and fixation were evaluated in respect to reattached tuberosities to the head fragment and the adequate restoration of the calcar area not showing any valgus or varus malalignment. Complete fracture healing was determined 3 months after surgery. Any failures such as secondary displacement, primary screw perforation, intraarticular cement leakage and avascular necrosis of the humeral head with concomitant screw cut-out were assessed.

RESULTS

In total, 24 patients (21 females; 3 males) at a median age of 77.5 (62-96) years were included. Five 2-part, twelve 3-part and seven 4-part fractures were detected. The measured median BMD value of 23 patients was 78.4 mg/cm³ (38.8-136.9 mg/cm³). Anatomical reduction was achieved in 50% of the patients. In most cases, the A level screws and the B1 screw were augmented with bone cement by a median of 7 (5-9) head screws used. Postoperative varus displacement was not detected in any of the patients. One patient (4.2%) sustained an early secondary displacement. Intraarticular cement leakage was detected in 3 patients (2 head-split fractures). Avascular necrosis of the humeral head was observed in 4 patients (16.7%). Revision surgery was necessary in four cases, using hemiarthroplasty twice and reverse shoulder arthroplasty the other two times.

CONCLUSION

Screw-tip augmentation in angular stable plating for proximal humerus fracture treatment showed a low secondary displacement rate of 4.2% in patients suffering from poor bone quality. Nevertheless, the occurrence of avascular necrosis of the humeral head with mainly severe fracture patterns observed in this study was higher compared to previously reported results in the literature. Cement augmentation in head-split fractures is not recommended, considering the high risk of an intraarticular cement leakage.

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.