Higher primary stability of tuberosity fixation in reverse fracture arthroplasty with 135° than with 155° humeral inclination

[Endoprosthesis in proximal humerus fractures -What is important?]

In cases of complex proximal humeral fractures a fracture prosthesis is an established treatment option. In the geriatric patient population, the use of reverse total shoulder arthroplasty is gaining in relevance. This article focuses on the specific requirements and challenges associated with the application of reverse total shoulder arthroplasty. Decisive for the success are a structured perioperative management, meticulous preoperative planning, thorough patient education and standardized protocols for infection and bleeding prophylaxis. Intraoperatively, emphasis is placed on precise implantation techniques and stable tuberosity fixation, of which the latter is essential for postoperative function. A humeral inclination of 135° has been shown to be associated with better tuberosity healing. Complications, such as scapular notching or instability can be minimized through an accurate surgical technique and optimized implant management. Postoperative care is tailored to the individual, employing either a shoulder abduction brace or an early functional rehabilitation approach. Overall, reverse shoulder arthroplasty provides an effective fracture treatment for geriatric patients, ensuring long-term functional and clinical benefits.

Reverse Shoulder Arthroplasty for Proximal Humerus Fractures: A Review of Current Evidence

PURPOSE OF REVIEW

The aim of this review is to summarize information published in the recent peer-reviewed literature on reverse shoulder arthroplasty (RSA) for proximal humerus fractures.

RECENT FINDINGS

Although there is still some debate regarding which may be the best treatment for proximal humerus fractures in certain age ranges, RSA seems to offer more predictable results than other surgical treatments for elderly patients. Successful tuberosity healing seems to correlate with better outcomes. Recent trends indicate interest in cementless fixation, fracture-specific stems and a 135-degree polyethylene opening angle. RSA provides a successful surgical solution for selected proximal humerus fractures. Indications, design features, and surgical execution have continued to evolve over the last few years.

Clinical and radiological outcome following trauma-related reverse shoulder arthroplasty

BACKGROUND

Reverse shoulder arthroplasty (RSA) is a frequently used therapy for complex proximal humeral fractures and posttraumatic disorders. The present study's purpose was to assess the clinical and radiological outcome of primary and secondary RSA, and to analyze the impact of refixation of the greater tuberosity (GT).

PATIENTS AND METHODS

28 patients with primary fracture RSA and 18 patients with RSA due to posttraumatic disorders were examined with a mean clinical follow-up of 2.5 ± 1.73 years. Operative details and radiographs were retrospectively reviewed. Additional analyses were performed for healed and non-healed GT in primary RSA.

RESULTS

Patients with fracture RSA had higher Constant-Murley score (CMS) than secondary RSA without reaching significance (p = 0.104). No significant difference was present for the quality of life measured by the Short Form 36 (SF 36) and the range of motion. In primary RSA, 78.6% GT healed anatomically. Compared to non-healed GT, patients with healed GT had a significantly higher CMS (p = 0.011), external rotation (p = 0.026) and forward flexion (p = 0.083), whereas DASH score was lower without a significant difference (p = 0.268). SF 36 showed no significant difference. Patients with healed GT had a more neutral glenoid version (p = 0.009).

CONCLUSION

Superior range of motion and clinical outcome scores were present for anatomically healed GT. Therefore, refixation of the tuberosities is recommended. Secondary RSA can result in inferior results compared to primary RSA, so patients need to be adequately informed.

The Evolution of Reverse Total Shoulder Arthroplasty and Its Current Use in the Treatment of Proximal Humerus Fractures in the Older Population

Proximal humerus fracture (PHF) is a common injury in the older population. While the majority of these fractures are treated non-operatively, a small subset of patients may benefit from surgical treatment. However, there continues to be an ongoing debate regarding the indications and ideal surgical treatment strategy. The use of reverse total shoulder arthroplasty (RTSA) has resulted in a paradigm shift in the treatment of PHFs in the older population. Unique biomechanical principles and design features of RTSA make it a suitable treatment option for PHFs in the older population. RTSA has distinct advantages over hemiarthroplasty and internal fixation and provides good pain relief and a reliable and reproducible improvement in functional outcomes. As a result, there has been an exponential increase in the volume of RTSA in the older population in last decade. The aim of this paper is to review the current concepts, outcomes and controversies regarding the use of RTSA for the treatment of PHFs in the older population.

[Fracture analysis, indication for endoprosthesis and implant selection in proximal humeral fractures]

Proximal humeral fractures (PHF) are the third most common fracture in humans and the incidence is increasing. There are basically three treatment strategies: conservative, joint-preserving reconstructive or joint-replacing procedures. In addition to fracture morphology, patient-specific and surgeon-specific factors are particularly important when deciding on treatment. The experience and training of the surgeon also play a decisive role. In the case of joint-preserving treatment, the risk of osteosynthesis failure and of sequelae of the fracture must always be assessed. If conservative or reconstructive treatment methods are not promising, the joint-replacing procedure is the treatment of choice. The anatomical fracture prosthesis is only indicated, if at all, for young patients with a destroyed humeral head with a preserved rotator cuff and large fragments of the tuberosities. In advanced age, the implantation of a reverse endoprosthesis is increasingly used for dislocated, multifragmentary PHF. In both procedures, the anatomical healing of the tuberosities has a significant impact on the functional outcome.

[Current trends in reverse fracture arthroplasty]

The reliable results of reverse arthroplasty have made this the preferred treatment method for non-reconstructable proximal humeral fractures. The individual consideration of the patient and the morphological features of the fractures are essential. Computed tomography (CT) images provide crucial information on the perfusion of the humeral head relevant for the prognosis and treatment. In this context a differentiation must be made between hard and soft criteria against a reconstruction. Tuberosities should be reduced whenever possible, because reverse arthroplasty with healed tuberosities provides a better range of motion and more strength for external rotation and anteversion, less complications and longer survival rates. In recent years the trend has been towards anatomical designs of prostheses with a humeral inclination of 135°. Revision rates for primary fracture prostheses are overall low with instability as the main reason for revision surgery, followed by periprosthetic fractures and infections. Reverse fracture arthroplasty has comparable or better clinical results compared to conservative treatment, osteosynthesis for geriatric patients, hemiarthroplasty and prosthesis implantation by elective surgery. Reverse arthroplasties, which were implanted in conditions of fracture sequelae, did not achieve significantly poorer clinical outcome at mid-term follow-up and can significantly improve shoulder function.

Prosthesis Designs and Tuberosity Fixation Techniques in Reverse Total Shoulder Arthroplasty: Influence on Tuberosity Healing in Proximal Humerus Fractures

Reverse total shoulder arthroplasty (RTSA) is increasingly used for the treatment of complex proximal humerus fractures and fracture sequelae. In 2021, half a dozen models of fracture stems are commercially available, reflecting its growing utility for fracture management. Prosthesis designs, bone grafting and tuberosity fixation techniques have evolved to allow better and more reliable fixation of tuberosities and bony ingrowth. Patients with anatomical tuberosity healing not only have an increased range of active anterior elevation and external rotation, but also experience fewer complications and longer prosthesis survival. This review provides an overview of recent evidence on basic and fracture-specific RTSA design features as well as tuberosity fixation techniques that can influence tuberosity healing.

Anterior deltoid muscle tension quantified with shear wave ultrasound elastography correlates with pain level after reverse shoulder arthroplasty

INTRODUCTION

Reverse shoulder arthroplasty (RSA) leads to medialization and distalization of the centre of rotation of the shoulder joint resulting in lengthening of the deltoid muscle. Shear wave ultrasound elastography (SWE) is a reliable method for quantifying tissue stiffness. The purpose of this study was to analyse if deltoid muscle tension after RSA correlates with the patients' pain level. We hypothesized that higher deltoid muscle tension would be associated with increased pain.

MATERIAL AND METHODS

Eighteen patients treated with RSA were included. Constant score (CS) and pain level on the visual analogue scale (VAS) were analysed and SWE was performed on both shoulders. All three regions of the deltoid muscle were examined in resting position and under standardized isometric loading.

RESULTS

Average patient age was 76 (range 64-84) years and average follow-up was 15 months (range 4-48). The average CS was 66 points (range 35-89) and the average pain level on the VAS was 1.8 (range 0.5-4.7). SWE revealed statistically significant higher muscle tension in the anterior and middle deltoid muscle region in patients after RSA compared to the contralateral non-operated side. There was a statistically significant correlation between pain level and anterior deltoid muscle tension.

CONCLUSION

SWE revealed increased tension in the anterior and middle portion of the deltoid muscle after RSA in a clinical setting. Increased tension of the anterior deltoid muscle portion significantly correlated with an increased pain level. SWE is a powerful, cost-effective, quick, dynamic, non-invasive, and radiation-free imaging technique to evaluate tissue elasticity in the shoulder with a wide range of applications.

LEVEL OF EVIDENCE

Diagnostic study, Level III.

Fracture-Specific and Conventional Stem Designs in Reverse Shoulder Arthroplasty for Acute Proximal Humerus Fractures-A Retrospective, Observational Study

Tuberosity healing and stem design can be outcome-dependent parameters in hemiarthroplasty for proximal humerus fractures (PHF). The relevance of fracture-specific stem design in reverse shoulder arthroplasty (RSA) is still a matter of debate. This retrospective study evaluates tuberosity healing and function for fracture specific stems (A) compared to conventional stems (B) in RSA for complex PHF in 26 patients (w = 21, mean age 73.5 years). Clinically, range of motion (ROM), Constant-Murley-Score (CS), Subjective Shoulder Value (SSV), and external rotation lag signs (ERLS) were evaluated. Healing of greater tuberosity (GT) and lesser tuberosity (LT), scapular notching, and loosening were examined radiologically. There were no statistical significant differences with regards to CS (A: 73 ± 11; B: 77 ± 9 points), SSV (A: 78% ± 11%; B: 84% ± 11%), external rotation (A: 18° ± 20°; B: 24° ± 19°), or internal rotation (A: 5.7 ± 2.2; B: 6.7 ± 2.8 CS-points) (p > 0.05). Mean forward flexion was superior for group A (p = 0.036). Consolidation of GT (82%) and LT (73%) was similar in both groups. Anatomical healing was slightly higher in group B (p > 0.05). Scapular notching was found in 27% (A) and 55% (B) (p > 0.05). RSA for PHF provides good to excellent clinical results. The quantitative and qualitative union rate for both cohorts was similar, indicating that fracture stems with open metaphyseal designs to allow for bone ingrowth do not improve tuberosity healing. ERLS correlates with a worse function in CS and ROM in all planes.