Treatment of equine superficial digital flexor tendonitis

A little surprising, surgery cases showed an improved % to recovery to race but no better results racing. I wonder why?
DrO

Intralesional bone marrow and superior check desmotomy is superior to conservative treatment of equine superficial digital flexor tendonitis
Equine Vet J. 2022 Jan 9. doi: 10.1111/evj.13553. Online ahead of print.
Authors
D J Murphy 1 , V Kö-Peternelj 2 , J W Aleri 1
Affiliations

1 School of Veterinary Medicine, College of Science, Health, Engineering and Education, Murdoch University, Western Australia, Australia.
2 Belvoir Equine Clinic, Lot 158 West Swan Rd, Belhus, Western Australia, Australia.

PMID: 35000213
DOI: 10.1111/evj.13553

Abstract

Background: Superficial digital flexor tendon (SDFT) injury is common in racehorses and a significant cause of lost training days and wastage in the industry.

Objectives: To compare the post-injury performance of Thoroughbred and Standardbred racehorses diagnosed with SDFT tendonitis treated with intralesional bone marrow and superior check desmotomy or managed conservatively and further, to compare this performance with that of uninjured racehorses.

Study design: Retrospective and case controlled.

Methods: Medical and race records of racehorses treated surgically or managed conservatively for SDFT tendonitis were collated. Signalment, lesion severity and treatment were identified and performance post-injury compared. Performance of the treatment groups was further assessed by comparison with uninjured racehorses matched for age, sex, number of starts pre-injury and randomly selected from the cases’ last races.

Results: The study population comprised 114 racehorses divided into surgical (39/114), conservative (38/114) and control groups (37/114). Horses that had surgery were more likely to return to racing than those managed conservatively [OR 4.7 95%CI (1.6-14.3), p= 0.006]. Standardbreds were more likely to return to race compared to Thoroughbreds [OR 4.0 95%CI 1.2-13.3), p=0.03)]. There was no statistical significant difference in average number of placings, average number of wins and post-injury earnings between the surgically treated and conservatively managed groups (p=0.9, p=0.9 and p=0.7 respectively). The average number of lifetime starts post-injury/post-selection between surgery, conservative and control groups were not statistically significantly different (p=0.2). Surgically treated horses had a statistically significantly shorter time to start post-injury compared to the conservative group (p=0.04).

Main limitations: The retrospective nature of the study precludes an actual fit as a non-randomised clinical trial and the non-randomised nature of the allocation of the treatment groups is biased.

Conclusions: Surgical intervention of superficial digital flexor tendonitis in racehorses suffering flexor tendon injury showed a higher likelihood of return to racing than conservative treatment.

Keywords: bone marrow; desmotomy; horse; performance; racehorses; tendonitis.