Does the REGENETEN Implant Actually Improve Rotator Cuff Repair Outcomes?
REGENETEN is a collagen implant used to augment rotator cuff repair or treat partial tears. It measurably reduces retear on imaging.
Overview
REGENETEN is a resorbable collagen implant placed on the cuff to augment a repair or induce tissue growth over a partial tear. Trial evidence shows it reduces retear on MRI.
Who this is for
REGENETEN is most often used in two settings in this practice: as an augmentation added to a standard suture-anchor repair of a full-thickness tear, and as a standalone treatment placed over a partial-thickness tear that doesn't yet meet the threshold for a formal takedown-and-repair. It is not a substitute for a real repair in a large, retracted, full-thickness tear — the implant is a tissue-inductive scaffold, not a load-bearing construct, and it has not been studied as a way to avoid repairing a tear that needs repairing.
Reasonable candidates include patients with a repairable full-thickness tear where the surgeon wants additional biologic support for the repair, and patients with a high-grade partial-thickness tear whose tendon has not yet failed enough to require takedown and repair. It is not appropriate for patients being counseled about a massive or chronic tear with poor tissue quality, and it should not be sold to a patient as a way to guarantee a better-feeling shoulder — the evidence doesn't support that claim yet. Dr. Raffo discusses this option with patients from across Montgomery County, including Bethesda and Germantown, as part of a broader conversation about surgical and biologic options for cuff tears.
How I approach it
REGENETEN is a biologic scaffold for rotator cuff tears. It is a piece of bovine (cow) achilles tendon. It is used to augment anchored repairs (in full thickness tears) or as the only implant in many partial thickness tears.
For full thickness tears, the Level I randomized data: adding the implant to a standard transosseous-equivalent repair cut the 12-month retear rate from 25.8% to 8.3% — roughly a two-thirds relative reduction (RR 0.32, 95% CI 0.13–0.83, P=.010) (Ruiz Ibán, Arthroscopy 2024), and that advantage held up at two years (35.1% versus 12.3% retear, P=.004) (ASES 2024 annual meeting paper).
However, in that same trial, the proportion of patients who reached a clinically meaningful improvement in outcome scores was statistically identical between groups — 76.7% versus 81.7% for Constant-Murley (P=.654), and 75% versus 80% for ASES (P=.829) (Ruiz Ibán, Arthroscopy 2024).
The operation
For augmentation of a standard repair, the implant is applied over the top of the repaired tendon after the primary suture-anchor fixation is complete, typically secured with a small number of additional absorbable staples so it sits directly on the bursal surface of the cuff.
It is now the main repair for partial-thickness tears. The implant is placed directly onto the intact bursal surface without taking down the remaining untorn tendon or repairing the tendon itself. It is meant to stimulate new tissue growth into the existing tendon over the following months. In both settings, the implant is resorbable and is not visible on imaging as a foreign material once incorporation occurs.
Where Surgeons Disagree
Does REGENETEN's retear reduction justify its routine use in full-thickness repairs?
I use it selectively — in tears and patients where I think the retear-reduction effect is worth the added cost and operative time — rather than as a routine addition to every repair.
The retear reduction is the most convincing single data point in this space: 8.3% versus 25.8% at 12 months, sustained at two years (Ruiz Ibán, Arthroscopy 2024). A separate registry of 272 patients also showed strong outcome improvement from baseline — ASES rising from 46.8 to 88.1, with 93.1% reaching a clinically meaningful improvement and a low 4.4% revision rate (Bushnell, Orthopaedic Journal of Sports Medicine 2021) — though that study had no comparison group, so it can't tell us how much of that improvement came from the implant versus the repair itself. The AAOS 2025 CPG rates bioinductive tendon implants at Quality: High, Strength: Strong (AAOS 2025 CPG), which is a notably confident guideline rating for a technology whose flagship comparative trial showed no difference in patient-reported outcome.
Where I’d be talked out of it
In a patient with a small, low-risk tear who is already very likely to heal well without augmentation, or in a patient who wants to minimize cost and operative time, I would not push for the implant. The honest summary I give every patient considering it is that the implant reliably improves what the MRI shows; it has not yet been shown to reliably improve what the patient reports feeling.
Risks and honest tradeoffs
The evidence base for REGENETEN is definitely mixed. The strong part: a Level I RCT showing a large, statistically significant reduction in radiographic retear, from 25.8% to 8.3% at one year and maintained at two years (Ruiz Ibán, Arthroscopy 2024).
Much of the remaining published support for the implant comes from single-arm registry data and small prospective series rather than controlled comparisons — a 272-patient registry with strong before-and-after outcome improvement but no control group (Bushnell, Orthopaedic Journal of Sports Medicine 2021), a 33-patient prospective cohort showing tissue fill-in on MRI in 95–100% of tears with only one progressing to full thickness (Schlegel, JSES 2021), and a 32-patient series reporting 0% retear at 12 months (Yoo, Medicina 2025). A broader systematic review of 17 studies and 1,062 tears found reported retear rates ranging widely, from 0% to 18% at five years for partial-thickness tears treated with the implant and 0% to 35% at two years for full-thickness tears (Benthami Kbibi, Acta Orthopaedica Belgica 2024) — a wide enough range that it should not be read as a guaranteed result.
Recovery and rehabilitation
Recovery after a REGENETEN-augmented repair follows the same general timeline as a standard rotator cuff repair, because the implant does not change the fundamental biology of tendon-to-bone healing or the need to protect the repair during that process. Most patients wear a sling for 3 weeks, begin passive motion early, and progress to active motion and strengthening over the following two to three months, reaching functional strength by four to six months in most cases (OrthoInfo: Rotator Cuff Tears — Surgical Treatment Options).
When the implant is used standalone over a partial-thickness tear without a formal repair, the protocol is typically less restrictive, since there is no anchor-based repair construct to protect, but the tendon still needs time to incorporate the new collagen scaffold — imaging in one study showed continued tendon thickening out to two years (Schlegel, JSES 2021).
Recovery milestones for full-thickness augmented repairs:
- Weeks 0–3: Sling protection; passive range of motion started, following the same protocol as the underlying repair.
- Weeks 4–8: Progression to active-assisted and active motion.
- Weeks 8–12: Strengthening program begins.
- Months 4–6: Functional motion and strength typically restored.
- Up to 2 years: Continued tendon remodeling and thickening on imaging has been documented out to two years in implant-augmented partial-thickness tears (Schlegel, JSES 2021).
Partial thickness tears have a much shorter recovery.
Weeks 0–3
Sling protection; passive range of motion started, following the same protocol as the underlying repair.
Weeks 4–8
Progression to active-assisted and active motion.
Weeks 8–12
Strengthening program begins.
Months 4–6
Functional motion and strength typically restored.
Up to 2 years
Continued tendon remodeling and thickening on imaging has been documented out to two years in…
Continued tendon remodeling and thickening on imaging has been documented out to two years in implant-augmented partial-thickness tears (Schlegel, JSES 2021).
Alternatives I considered
REGENETEN is mainly added to full-thickness repairs when tissue quality is poor and the risk for failure is deemed to be high.
Platelet-rich plasma is another biologic option; meta-analyses show a modest reduction in retear with PRP (roughly 13–16.5% versus 18–23.6% without) but, similarly to REGENETEN, little to no consistent improvement in patient-reported outcome scores.
Biologics used
Ready to be seen?
Appointments are booked through Maryland Orthopedic Specialists, where Dr. Raffo practices.
Frequently Asked Questions
Clinical References
- Ruiz Ibán MÁ, et al. Augmentation of a Transosseous-Equivalent Repair with a Bioinductive Collagen Implant: RCT. Arthroscopy. 2024;40(6):1760-73.
- ASES 2024 Annual Meeting Paper 17 — 2-year RCT results.
- Bushnell BD, et al. Bioinductive collagen implant registry outcomes. Orthop J Sports Med. 2021.
- Schlegel TF, et al. Isolated bioinductive repair of partial-thickness rotator cuff tears: 2-year MRI and clinical results. J Shoulder Elbow Surg. 2021;30(8):1938-48.
- Yoo J, et al. Bioinductive implant for Ellman grade I–II partial tears. Medicina (Kaunas). 2025.
- Benthami Kbibi M, et al. Bioinductive collagen implant systematic review. Acta Orthop Belg. 2024.
- FDA 510(k) K222501 — REGENETEN Bioinductive Implant, Smith & Nephew (Class II surgical mesh).
- AAOS. Management of Rotator Cuff Injuries — Evidence-Based Clinical Practice Guideline, 2025.
- PRP retear meta-analysis.
- PRP retear meta-analysis. 2025.
Related Procedures
Arthroscopic Rotator Cuff Repair
Dr. Raffo has performed 1,500+ arthroscopic rotator cuff repairs. This page covers who is a candidate, construct choice, and honest retear rates by tear size and age.
Learn more shoulderPartial-Thickness Rotator Cuff Tear Treatment
Partial-thickness rotator cuff tears are treated differently depending on how much of the tendon is torn. Dr. Raffo explains the more-than-50%-thickness rule and when it applies.
Learn more