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Home / Equine Research Bank / Open Vet J / Autologous conditioned serum IRAP efficacy for tendon and li...
Open veterinary journal2025; 15(8); 3787-3793; doi: 10.5455/OVJ.2025.v15.i8.43

Autologous conditioned serum IRAP efficacy for tendon and ligament injuries in horses: An observational study.

Abstract: Tendon and ligament injuries in equine athletes pose significant challenges, often leading to prolonged recovery, reduced performance, and increased risk of reinjury. Current treatment strategies, including conservative and surgical approaches, have shown limited success in fully restoring tendon integrity. Autologous blood derivatives, such as autologous conditioned serum (ACS), have emerged as potential regenerative therapies. However, the clinical efficacy of ACS in the treatment of equine tendinopathies remains under investigation. Unassigned: This study aimed to compare the clinical outcomes between intralesional ACS injections and conservative treatment in horses diagnosed with superficial digital flexor tendon (SDFT), deep digital flexor tendon (DDFT), and suspensory ligament (SL) injuries. Unassigned: This retrospective observational case-control study used clinical data from 100 horses evaluated for lameness between 2017 and 2022. Horses were categorized into two groups: the IRAP group ( = 48), which received three intralesional ACS injections at 1-week intervals, and the NO-IRAP group ( = 52), which was treated conservatively with NSAIDs and a structured rehabilitation program. Lameness assessments and ultrasonographic evaluations were performed at initial presentation and follow-up at 4, 8, and 12 weeks. The statistical analyses compared changes in lameness scores between the two groups. Unassigned: At 4 weeks, improvement in lameness was observed in 51.5% and 55.6% of the IRAP and NO-IRAP groups, respectively. At 8 weeks, improvement rates were 47% and 42.2%, respectively. By 12 weeks, 60.7% of the IRAP group and 55% of the NO-IRAP group showed improvement. However, a subset of horses in the IRAP group experienced transient worsening of lameness (8.5%-17.7%). Stratification by lesion type revealed better outcomes in the IRAP group for SDFT (58.3% 48%) and SL (51.2% 36%) injuries, whereas the NO-IRAP group had superior results for DDFT injuries (60.9% 46.2%). Unassigned: The study suggests that ACS treatment enhances tendon and ligament healing, particularly in SDFT and SL injuries. However, the transient worsening of lameness observed in some horses receiving ACS warrants further investigation. Although these findings support the potential benefits of ACS, controlled randomized clinical trials are needed to validate its efficacy and optimize treatment protocols for equine tendon and ligament pathologies.
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Publication Date: 2025-08-31 PubMed ID: 41036008PubMed Central: PMC12483392DOI: 10.5455/OVJ.2025.v15.i8.43Google Scholar: Lookup
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  • Journal Article
  • Observational Study
  • Veterinary

Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

Overview

  • This study evaluated the effectiveness of autologous conditioned serum (ACS), delivered via intralesional injections, compared to conservative treatment for tendon and ligament injuries in horses.
  • The research focused on equine superficial digital flexor tendon (SDFT), deep digital flexor tendon (DDFT), and suspensory ligament (SL) injuries, analyzing clinical outcomes from 100 cases over a 12-week period.

Background and Rationale

  • Tendon and ligament injuries are common and challenging issues in equine athletes, often causing long recovery times and diminished performance.
  • Traditional treatments include conservative care (like NSAIDs and rehabilitation) and surgical repair, but these often fail to fully restore the tendon or ligament to its original state.
  • Autologous conditioned serum (ACS), a blood derivative enriched with anti-inflammatory and regenerative factors, has been proposed as a novel treatment option to promote healing, but its clinical effectiveness is not fully established.

Study Design and Methods

  • This was a retrospective observational case-control study using clinical records from 100 horses treated between 2017 and 2022.
  • Horses were divided into two groups:
    • IRAP group (n=48): Received three ACS intralesional injections spaced one week apart.
    • NO-IRAP group (n=52): Received conservative treatment consisting of non-steroidal anti-inflammatory drugs (NSAIDs) and a structured rehabilitation protocol.
  • Lameness scoring and ultrasound evaluations were performed at baseline and then at 4, 8, and 12 weeks to monitor progress.
  • The primary outcome measure was improvement in lameness scores over time, compared between the two groups.

Results

  • At 4 weeks:
    • 51.5% of horses treated with ACS showed improvement in lameness.
    • 55.6% of horses under conservative treatment improved.
  • At 8 weeks:
    • 47% improvement rate in the ACS group.
    • 42.2% improvement in the NO-IRAP group.
  • At 12 weeks:
    • 60.7% of ACS-treated horses improved.
    • 55% of those treated conservatively improved.
  • Some horses in the ACS group experienced a temporary worsening of lameness symptoms, ranging from 8.5% to 17.7% depending on timepoints.
  • When accounting for injury type:
    • ACS treatment showed better outcomes for SDFT injuries (58.3% improved vs. 48% in controls) and suspensory ligament injuries (51.2% vs. 36%).
    • Conservative treatment was more effective for DDFT injuries (60.9% improved vs. 46.2% with ACS).

Interpretation and Implications

  • The findings suggest that ACS may enhance healing particularly for superficial digital flexor tendon and suspensory ligament injuries.
  • The greater improvement in these injuries might be due to the biological effects of ACS in reducing inflammation and promoting tissue regeneration.
  • The transient lameness worsening in some horses receiving ACS could indicate an initial inflammatory reaction or other side effects that require further study.
  • The study’s observational and retrospective design limits the strength of conclusions; randomized controlled trials are needed to confirm the benefits and refine treatment protocols.
  • Results contribute to the growing evidence supporting autologous blood products as adjunct therapies in equine tendon and ligament repair.

Conclusion

  • Autologous conditioned serum shows promise as a treatment to improve healing outcomes in certain equine tendon and ligament injuries.
  • Clinical benefits were particularly notable for SDFT and suspensory ligament lesions, while conservative treatment sometimes performed better for DDFT injuries.
  • Future prospective and randomized studies are necessary to validate these results, understand the cause of transient worsening, and optimize ACS application in veterinary sports medicine.

Cite This Article

APA
Tommasa SD, Raspe S, Farí G, Imperante A, Brehm W. (2025). Autologous conditioned serum IRAP efficacy for tendon and ligament injuries in horses: An observational study. Open Vet J, 15(8), 3787-3793. https://doi.org/10.5455/OVJ.2025.v15.i8.43

Publication

Open veterinary journal
ISSN: 2218-6050
NlmUniqueID: 101653182
Country: Libya
Language: English
Volume: 15
Issue: 8
Pages: 3787-3793

Researcher Affiliations

Tommasa, Simone Della
  • Department for Horse, University of Leipzig, Leipzig, Germany.
Raspe, Sarah
  • Department for Horse, University of Leipzig, Leipzig, Germany.
Farí, Giacomo
  • Department of Biological and Enviromental Science and Technologies (Di. Ste. B.A.), University of Salento, Lecce, Italy.
Imperante, Annarita
  • Field Veterinary Surgeon, Bari, Italy.
Brehm, Walter
  • Department for Horse, University of Leipzig, Leipzig, Germany.

MeSH Terms

  • Animals
  • Female
  • Male
  • Case-Control Studies
  • Horse Diseases / therapy
  • Horses / injuries
  • Lameness, Animal / therapy
  • Ligaments / injuries
  • Retrospective Studies
  • Serum
  • Tendon Injuries / veterinary
  • Tendon Injuries / therapy
  • Treatment Outcome

Conflict of Interest Statement

None.

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