Primary Versus Salvage Reverse Total Shoulder Arthroplasty for Displaced Proximal Humerus Fractures in the Elderly: A Systematic Review and Meta-analysis

Development of a New Model of Humeral Hemiarthroplasty in Rats

PURPOSE

In vivo models are anatomically comparable to humans allowing to reproduce the patterns and progression of the disease and giving the opportunity to study the symptoms and responses to new treatments and materials. This study aimed to establish a valid and cost-effective in vivo rat model to assess the effects of implanted shoulder hemiarthroplasty materials on glenoid articular cartilage wear.

METHODS

Eight adult male Wistar rats underwent right shoulder hemi-arthroplasty. A stainless steel metal bearing was used as a shoulder joint prosthesis. X-rays were performed one week after surgery to verify correct implant position. Additional X-rays were performed 30 and 60 days post-implantation. Animals were sacrificed 24 weeks after implantation. All specimens were evaluated with micro-CT for cartilage and bone wear characteristics as well as histologically for signs of osteoarthritis. Samples were compared to the non-operated shoulders.

RESULTS

All animals recovered and resumed normal cage activity. All X-rays demonstrated correct implant positioning except for one in which the implant was displaced. Histologic evaluation demonstrated arthritic changes in the implanted shoulder. Decreased Trabecular thickness and Trabecular Spacing were documented among the implanted parties (p < .05). Bone Mineral Density and Tissue Mineral Density were reduced in the operated shoulder although not significantly (p = .07).

CONCLUSIONS

This study demonstrated significant glenoid cartilage wearing in the operated shoulder. Furthermore, the presence of an intra-articular hemiarthroplasty implant diminished underlying glenoid bone quality. This novel, in vivo-model will enable researchers to test implant materials and their effects on cartilage and bone tissue in a cost-effective reproducible rat model.

Single-Stage Bilateral Reverse Shoulder Arthroplasty for a Bilateral Four-Part Fracture Dislocation of the Proximal Humerus in an Elderly Patient: A Case Report

Proximal humerus fractures (PHFs) are a common type of fracture in adults. Although PHFs are common, bilateral presentation is extremely rare. Most PHFs are treated conservatively. In this report, we describe a 69-year-old right-hand-dominant male patient who was involved in a high-impact motor vehicle accident (MVA). The patient's upper limbs were in a fully extended position while he was holding the driving wheel, where he sustained a side impaction to the car by a hard object that caused bilateral four-part PHF with dislocation, which was confirmed on radiological investigations. The orthopedic surgery team believed that surgical treatment was necessary and ideal for these bilateral fracture dislocations, specifically bilateral reverse total shoulder arthroplasty (RTSA). This is due to multiple factors, including the risk of humeral head avascular necrosis (AVN), the patient's advanced age, low demand, poor bone stock, osteoporosis, and a non-fixable fracture pattern. The patient underwent a single-stage bilateral RTSA procedure, which was well tolerated. He was optimized postoperatively. The post-operative X-ray showed good and satisfactory implant positions and orientation. Functional assessment using the Constant-Murley Score (CMS) and Disabilities of the Arm, Shoulder and Hand (DASH) score were calculated at three-months follow-up (right-left: 50-60 and 41-14, respectively), at five-months follow-up (right-left: 34-66 and 38-14, respectively), and at eight-months follow-up (right-left: 40-68 and 24-7.5, respectively). Follow-up X-rays revealed good tuberosities healing, and no loosening or scapular notching. In addition, pain was assessed on a numerical rating scale (NRS), which demonstrated fast pain relief. Short-term follow-up with the patient demonstrated that he was satisfied with the surgery, especially the left side with a pain score on the NRS of one. We selected to share our experience of this complex case with our peers in the field of orthopedic surgery worldwide so that such a procedure could be implemented in similar cases to ensure satisfactory outcomes following bilateral four-part PHF with dislocation.

Functional outcomes of reverse total shoulder arthroplasty in Boileau class 1 and class 2 proximal humeral fracture sequelae: A meta-analysis and systematic review

Background

Reverse total shoulder arthroplasty (RTSA) is an increasingly popular salvage treatment option for proximal humeral fracture (PHF) sequelae. This meta-analysis aimed to conduct a pooled analysis of functional outcomes of RTSA in PHF sequelae, with subgroup analysis comparing between intracapsular (Class 1) and extracapsular (Class 2) PHF sequelae.

Methods

A multi-database search (PubMed, OVID, EMBASE) was performed according to PRISMA guidelines on 27th July 2020. Data from all published literature meeting inclusion criteria were extracted and analysed.

Findings

Eleven studies were included, comprising 359 shoulders (167 Class 1 and 192 Class 2). The mean age was 68.2 years, and the mean time between injury and surgery was 49 months, (1-516 months). Constant score and forward flexion improved by 31.8 (95%CI: 30.5-33.1, p < 0.001) and 60o (95%CI: 58o-62o, p < 0.001) respectively between pre-operative and post-operative values for both groups. Constant scores were better in Class 1 patients (MD = 3.60, 95%CI: 1.0-6.2, p < 0.001) pre-operatively and post-operatively (MD = 7.4, 95%CI: 5.8-9.0, p < 0.001). Forward flexion was significantly better in Class 1 patients (MD = 13o, 95%CI: 7o-17o, p < 0.001) pre-operatively, but was slightly better in Class 2 patients post-operatively (MD = 7o, 95%CI: 4o-10o, p < 0.001). Overall complication rate was 16.8%.

Conclusion

Salvage RTSA is effective for PHF sequelae, with multiple factors contributing to the high complication rate.

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.

Reverse shoulder arthroplasty vs. hemiarthroplasty for the treatment of osteoporotic proximal humeral fractures in elderly patients: A systematic review and meta‑analysis update

The present meta-analysis was conducted to compare the safety and effectiveness of reverse shoulder arthroplasty (RSA) and hemiarthroplasty (HA) in the treatment of osteoporotic proximal humeral fractures in elderly patients. The Embase, Pubmed Central, Cumulative Index to Nursing and Allied Health Literature, ProQuest Dissertations and Theses, Cochrane Library and Chinese Biomedical databases were searched between January 2009 and January 2022 to identify relevant studies. According to the search strategy, a total of 210 associated studies were retrieved and 16 were finally included. Review Manager 5.4 software was used for the data analysis. This study indicated that patients in the RSA group had significantly improved treatment outcomes compared with patients in the HA group, as assessed by Constant-Murley Shoulder Outcome Score (95% CI, 1.69-3.76; P<0.001), American Shoulder and Elbow Surgeons score (95% CI, 11.81-24.88; P<0.001) and shoulder range of motion (ROM; 95% CI, 3.41-9.07; P<0.001). However, the HA group was superior to the RSA group in terms of the Oxford Shoulder score (95% CI, 2.89-11.11; P<0.001). There was no significant statistical difference between the two groups in terms of the Disabilities of the Arm, Shoulder and Hand score and complications. Overall, for the treatment of osteoporotic proximal humeral fractures in the elderly, the RSA group had improved postoperative ROM and functional scores compared with the HA group, without significant difference in the incidence of complications. However, HA remains a safe and reliable treatment option.

Proximal humerus fractures: anatomy, diagnosis and management

Proximal humeral fractures are common with a bimodal distribution and sex discrepancy, affecting younger men and older women. The presentation of a proximal humeral fracture can vary greatly because of this bimodal distribution and the associated differences in mechanism of injury.

Initial management should involve assessment of life- and limb-threatening injuries as outlined by the British Orthopaedic Association Standards for Trauma, with particular attention paid to axillary nerve function and vascular status. Initial imaging should involve orthogonal X-rays in three planes to determine fracture characteristics and exclude glenohumeral dislocation. Computed tomography imaging improves interobserver agreement and is the gold standard in determining fracture management.

Management depends on fracture pattern, patient functionality and bone stock. Most patients with proximal humeral fractures achieve good functional outcomes via conservative methods (sling support and early, graded mobilisation), although there is a lack of evidence in certain populations, including younger patients. Surgery is required for open fractures and more complex fracture patterns where there is a risk of avascular necrosis of the humeral head, unacceptable impairment of functionality or neurovascular compromise. Surgical techniques can be head-sparing or involve replacement of the humeral head. There are several head-sparing techniques, each with different cost–benefit and complication profiles with no one technique superior to any other. However, improvements in plate technology may render open reduction internal fixation a more suitable technique, particularly in younger patients. Head replacement techniques (hemiarthroplasty and reverse shoulder arthroplasty) are indicated when the risk of avascular necrosis is too high or in older patients with osteoporotic bone. In these patients, reverse shoulder arthroplasty is preferred as it achieves better functional results than hemiarthroplasty. Complication rates vary depending on the fracture configuration and the course of management undertaken.