Functional outcome and CEUS‐assessed deltoid muscle vitality after fracture‐specific versus standard prosthetic design in reverse shoulder arthroplasty for trauma

Abstract

Functional outcome after reverse-shoulder-arthroplasty (RSA) in proximal humerus fractures (PHF) depends on deltoid muscle integrity and successful reattachment of the tuberosities for best possible recovery of rotator-cuff function. In this monocentric, prospective, randomized, controlled trial we investigated whether a reverse-fracture-prosthesis (RFP) with a metaphyseal fenestrated stem achieved superior shoulder and muscle function compared to a common reverse-prosthesis (RP) design for patients with PHF. Our hypothesis was that patients with RFP may achieve a superior healing rate of the greater tuberosity (GT) compared to patients receiving RP, which translates to significantly higher clinical outcome and functional scores as well as differences in deltoid muscle microperfusion. Forty-four patients with PHF were randomized preoperatively to one of the prosthesis types in RSA between 2018 and 2020 (22 with RFP and 22 with RP) and prospectively assessed 6 months after surgery. We assessed osteointegration of the GT with radiographs 1 day and 6 months postoperatively and examined shoulder function and patient satisfaction by using established shoulder scores. A contrast-enhanced ultrasound (CEUS) examination of both shoulders was performed to quantify intramuscular blood flow and evaluate vitality of the deltoid muscle. None of the functional and psychosocial scores or radiographs and ultrasound examinations showed significant differences between the RSA designs. The constant-Murley score (p = 0.384) and active anterior-elevation-abduction, and external rotation were comparable between the RFP and RP group. Similar healing rates of the GT were observed (p = 0.655).CEUS-assessed deltoid microperfusion revealed equivalent muscle vitality for both groups (p = 0.312). Level of evidence: Level II; Randomized Controlled Trial;Treatment Study. Clinical significance: The radiographic evaluation for the investigation of the GT healing rate indicates that the proclaimed benefits of the fracture prosthesis with fenestration design might not be as great as expected.

The statistical fragility of the management options for reverse shoulder arthroplasty: a systematic review of randomized control trial with fragility analysis

“…Eleven RCTs (57.9%) were Appropriately Statistically Powered (ASP) meaning they recruited a sufficient sample size to satisfy a requirement of at least 80% power, 9 , 10 , 16 , 19 , 20 , 24 , 33 , 35 , 40 , 43 , 48 while 8 RCTs (42%) were statistically underpowered (SUP) as they did not recruit a population sufficient to achieve 80% power. 7 , 15 , 18 , 23 , 41 , 42 , 44 , 45 The ASP subgroup had a greater median trial FI than the SUP group at 5 (4.50-5) vs. 4 (3.75-4.13). We observed an association between higher powered studies and those with higher FIs, with data shown fully in Table II .…”

“…The quality of evidence was assessed using the ROB-II tool. 38 No RCTs were found to be at a high ROB, 13 were found to have a low ROB, 9 , 10 , 15 , 19 , 20 , 23 , 24 , 33 , 40 , 43 , 44 , 45 , 48 while for 6 there were some concerns about potential bias 7 , 16 , 18 , 35 , 41 , 42 ( Supplementary Appendix S1 ). The current impact factor of the journals in which the included RCTs are published had a mean of 3.6 ± 0.6, with 14 (74%) of the RCTs published in the Journal of Shoulder and Elbow Surgery, 2 in the Journal of Bone and Joint, and 1 each in Journal of Orthopaedic Research, Journal of Orthopaedic Trauma, and Archives of Orthopaedic and Trauma Surgery.…”

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

“…Although there is some evidence that fracture stem is associated with higher tuberosity healing in HA, there is insufficient evidence in literature supporting superiority of a fracture stem over standard stem in RTSA [ 67 , 68 ]. Multiple retrospective studies and systematic reviews report conflicting evidence with respect to tuberosity healing and or shoulder function when using a fracture stem compared to a standard humeral stem RTSA for PHFs [ 66 , 68 , 69 , 70 , 71 , 72 , 73 , 74 ].…”