Excessive granulation tissue: Proud flesh, a review of the research

Other than the rejection of caustic treatments not much has changed with treating proud flesh (exuberant granulation tissue) in the last 50 years. Still a poorly understood problem and for a quick take on recommended treatment see the result sections at the bottom. For more on the proper treatment read the article associated with this forum.
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Excessive granulation (t)issue: A narrative and scoping review of basic and clinical research of the equine distal limb exuberant wound healing disorder
Vet J. 2022 Jan 27;105790.
Authors
Nadia Ayurini Anantama 1 , Charis Du Cheyne 2 , Ann Martens 3 , Susanne Pauline Roth 4 , Janina Burk 5 , Ward De Spiegelaere 2 , Jule Kristin Michler 6
Affiliations

1 Institute of Veterinary Anatomy, Histology and Embryology, Leipzig University, An den Tierkliniken 43, 04103 Leipzig, Germany.
2 Department of Morphology, Ghent University, Salisburylaan 133, B-9820 Merelbeke, Belgium.
3 Department of Surgery and Anaesthesiology of Domestic Animals, Ghent University, Salisburylaan 133, B-9820 Merelbeke, Belgium.
4 Veterinary Teaching Hospital, Department for Horses, University of Leipzig, An den Tierkliniken 21, 04103 Leipzig, Germany.
5 Equine Clinic (Surgery, Orthopedics), Giessen University, Frankfurter Str. 108, 35392 Gießen, Germany.
6 Institute of Veterinary Anatomy, Histology and Embryology, Leipzig University, An den Tierkliniken 43, 04103 Leipzig, Germany.

Abstract

Exuberant granulation tissue (EGT) is often observed during second intention wound healing in horses. Despite its impact on wound care, the basic mechanisms leading to EGT are still unclear and effective strategies to prevent and/or treat EGT are lacking. The development of EGT is a poorly understood, multifactorial process involving hyperproliferating fibroblasts and malfunctional differentiation of keratinocytes, suboptimal wound contraction, dysfunctional vascularization, and chronic inflammation. To consolidate and describe basic and clinical research literature on EGT and to identify knowledge gaps and opportunities for future research, a search was systematically conducted using predefined search terms. Subsequently, a scoping review was conducted using specific criteria to select the peer-reviewed literature that described methods to treat and/or prevent EGT. Proposed mechanisms of effects as well as results and main conclusions were extracted and tabulated. The systematic search resulted in 1062 publications in PubMed and 767 in Web of Science. Twenty additional studies were later included. Of these, 327 studies were reviewed for the narrative review on basic research and 35 controlled clinical trials were eligible for the scoping review. All 35 studies were conducted in university hospitals, and all but one involved surgically induced non-infected wounds. The study population was predominantly horses (n = 230) with a small number of ponies (n = 18) and donkeys (n = 14). In conclusion, there remains a strong need for evidence-based recommendations on EGT treatment, preferably using multi-centre studies that represent the general population of horses, include higher numbers of animals, and are performed in naturally occurring wounds. This narrative and scoping review also emphasizes the importance of incorporating basic research knowledge in the study design of clinical trials.

Discussion
The standard treatment of EGT remains focused on single or repeated resection of any tissue that grows above the wound margins. This is considered to be a ‘fast, precise, and selective method of control’ (Dart et al., 2002b) that has no disadvantage apart from severe, though self-limiting, bleeding. Usually, a bandage is applied to the affected region. Surgical resection creates an evenly levelled wound surface and sets a new stimulus for healing