Onlay vs Inlay Techniques for Shoulder Replacement

Overseen By Grace SanAgustin, BSN

Age: 18+

Sex: Any

Trial Phase: Academic

Sponsor: William Beaumont Hospitals

Disqualifiers: Rheumatoid arthritis, Infection, Acute trauma, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: 4

Duration: Surgery and immediate postoperative care

154 Participants Needed

Trial Summary

What is the purpose of this trial?

The goal of this study is to compare the effect of different ways to place the component that goes at the top of the humerus (upper arm) in reverse total shoulder replacement. Some surgeons place the humeral tray component sitting on the bone while others place it in the bone. Changing the way that the humeral component is placed may change how much the arm can raise up or turn out/in after surgery for some patients. This study compares patients with inlay humeral component (tray sits in the upper arm bone) versus onlay humeral component (tray sits on top of the upper arm bone) to see if there are differences in range of motion or function after surgery.

Will I have to stop taking my current medications?

The trial information does not specify whether you need to stop taking your current medications.

What data supports the effectiveness of the inlay and onlay humeral components for shoulder replacement treatment?

Research shows that both inlay and onlay humeral components used in reverse shoulder arthroplasty (a type of shoulder replacement) have been studied for their effectiveness. Studies have compared their revision rates (how often a replacement needs to be redone) and functional outcomes, but there is no clear agreement on which design is better. Both designs have been associated with improved clinical outcomes in shoulder replacements. ^{1 2 3 4 5}

How do inlay and onlay humeral components differ in shoulder replacement treatment?

Inlay and onlay humeral components are two different designs used in shoulder replacement surgery. The inlay design places the humeral tray within the bone, while the onlay design positions it on top of the bone. These designs aim to improve shoulder function, but there is no clear consensus on which is better. ^{1 4 5 6 7}

Research Team

Alex Martusiewicz, MD

Principal Investigator

Beaumont Health

Eligibility Criteria

This trial is for adults over 18 who need a reverse total shoulder arthroplasty due to rotator cuff tears or arthritis, and can rotate their arm outward. It's not for those with previous open shoulder surgery, cognitive impairments, pregnancy, minors, or conditions like rheumatoid arthritis.

Inclusion Criteria

I have been diagnosed with a severe shoulder condition due to a tear or arthritis.

I can rotate my arm outward past its neutral position without lag.

I am 18 years old or older.

Exclusion Criteria

I am having or have had a joint replacement redone.

I have had open shoulder surgery before.

I have been diagnosed with rheumatoid arthritis, an infection, acute trauma, or instability.

Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants undergo reverse total shoulder arthroplasty with either inlay or onlay humeral component

Surgery and immediate postoperative care

1 visit (in-person)

Follow-up

Participants are monitored for range of motion, strength, and functional outcomes at 3 months, 12 months, and 24 months postoperatively

24 months

3 visits (in-person)

Treatment Details

Interventions

• Inlay Humeral Component
• Onlay Humeral Component

Trial Overview The study compares two surgical techniques of placing the humeral component in shoulder replacement: 'inlay' (inside the bone) versus 'onlay' (on top of the bone), using Tornier Ascend Flex stem and Perform Stem Reverse+ implants.

Participant Groups

Group I: Onlay Component-Tornier Ascend Flex stem Active Control 1 Intervention

Reverse Total Shoulder Arthroplasty using onlay component (tray placed at top of humerus)

Group II: Inlay Component-Tornier Perform Stem Reverse+ Active Control 1 Intervention

Reverse Total Shoulder Arthroplasty using inlay component (tray placed in humerus)

Who Is Running the Clinical Trial?

William Beaumont Hospitals

Lead Sponsor

Trials

153

Recruited

113,000+

Stryker Nordic

Industry Sponsor

Trials

35

Recruited

4,400+

Findings from Research

In a study of 6707 patients, the inlay humeral components (in-RSA) in reverse shoulder arthroplasty showed a significantly lower revision rate compared to onlay components (on-RSA), indicating better medium-term implant survival.

While the onlay components had better functional outcomes at 6 months post-surgery, this difference was not clinically significant, and by 5 years, both designs showed similar functional outcomes.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Medium-term results of inlay vs. onlay humeral components for reverse shoulder arthroplasty: a New Zealand Joint Registry study. Zhou, Y., Mandaleson, A., Frampton, C., et al.[2023]

The study analyzed 12 CT scans to create a 3D biomechanical model of the shoulder, testing 17 different positions for the humeral tray in reverse shoulder arthroplasty, revealing that the direction of the offset significantly affects impingement and muscle functionality.

Maximizing impingement-free range of motion was best achieved with a posterolateral tray offset, while maximizing muscle moment arms required a medial tray offset, indicating that optimal tray placement should be tailored to individual patient needs due to the conflicting outcomes.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effect of humeral tray placement on impingement-free range of motion and muscle moment arms in reverse shoulder arthroplasty. Glenday, J., Kontaxis, A., Roche, S., et al.[2020]

In a study of 95 patients who underwent anatomic total shoulder arthroplasty, the positioning of the humeral articular component did not significantly affect patient-reported outcomes, such as pain and shoulder function, after an average follow-up of 4.3 years.

Despite 62% of patients experiencing a shift in the center of rotation greater than 2 mm, there were no significant correlations between the radiographic measurements of component positioning and improvements in functional scores, suggesting that other factors may influence postoperative recovery.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Does prosthetic humeral articular surface positioning associate with outcome after total shoulder arthroplasty? Chalmers, PN., Granger, EK., Orvets, ND., et al.[2018]

In a systematic review of 12 studies involving 1447 patients, both inlay and onlay humeral designs in reverse total shoulder arthroplasty showed significant clinical improvements, with the inlay design yielding a higher American Shoulder and Elbow Surgeons score.

While the onlay design provided slightly better postoperative motion, it was associated with a lower rate of scapular notching but a higher rate of scapular spine fractures, highlighting the need for tailored surgical approaches based on patient risk factors.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Inlay versus onlay humeral design for reverse shoulder arthroplasty: a systematic review and meta-analysis. Larose, G., Fisher, ND., Gambhir, N., et al.[2023]

In a review of four studies involving 298 patients, onlay humeral components in reverse shoulder arthroplasty (RSA) showed significantly better external rotation compared to inlay components, indicating a potential advantage in shoulder mobility.

The onlay design also had a lower incidence of scapular notching (7.74%) compared to the inlay design (23.18%), suggesting it may reduce complications related to shoulder anatomy, although both designs resulted in similar overall patient-reported outcomes.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Onlay versus inlay humeral components in reverse shoulder arthroplasty: A systematic review and meta-analysis. Jackson, GR., Meade, J., Young, BL., et al.[2023]

In a study using 20 fresh-frozen cadaveric shoulders, inlay humeral implants for reverse total shoulder arthroplasty (rTSA) resulted in lower rotator cuff forces compared to onlay implants, which may lead to less muscle fatigue and potentially better long-term outcomes for patients with an intact rotator cuff.

However, inlay implants also showed reduced passive elevation range of motion (ROM) compared to onlay implants, indicating a trade-off between muscle force requirements and joint mobility after surgery.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Inlay versus onlay humeral components in reverse total shoulder arthroplasty: a biorobotic shoulder simulator study. Zitnay, JL., Tashjian, RZ., Walch, G., et al.[2023]

In a study of 150 patients who underwent reverse shoulder arthroplasty (RSA) with either inlay or onlay humeral tray designs, both groups showed similar improvements in range of motion and patient-reported outcomes after a follow-up of at least 2 years.

There were no significant differences in complication rates, including revision surgeries and scapular notching, between the inlay and onlay designs, suggesting that the choice of humeral tray design may not impact clinical outcomes for patients with glenohumeral osteoarthritis and intact rotator cuffs.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Lateralized glenosphere reverse shoulder arthroplasty: inlay and onlay designs have similar clinical outcomes in patients with glenohumeral osteoarthritis. Meshram, P., Joseph, J., Zhou, Y., et al.[2022]

References

1. United States pubmed.ncbi.nlm.nih.gov

Medium-term results of inlay vs. onlay humeral components for reverse shoulder arthroplasty: a New Zealand Joint Registry study. [2023]

2. England pubmed.ncbi.nlm.nih.gov

Effect of humeral tray placement on impingement-free range of motion and muscle moment arms in reverse shoulder arthroplasty. [2020]

3. United States pubmed.ncbi.nlm.nih.gov

Does prosthetic humeral articular surface positioning associate with outcome after total shoulder arthroplasty? [2018]

4. United States pubmed.ncbi.nlm.nih.gov

Inlay versus onlay humeral design for reverse shoulder arthroplasty: a systematic review and meta-analysis. [2023]

5. United States pubmed.ncbi.nlm.nih.gov

Onlay versus inlay humeral components in reverse shoulder arthroplasty: A systematic review and meta-analysis. [2023]

6. United States pubmed.ncbi.nlm.nih.gov

Inlay versus onlay humeral components in reverse total shoulder arthroplasty: a biorobotic shoulder simulator study. [2023]

7. United States pubmed.ncbi.nlm.nih.gov

Lateralized glenosphere reverse shoulder arthroplasty: inlay and onlay designs have similar clinical outcomes in patients with glenohumeral osteoarthritis. [2022]