A novel technique of taking tendon biopsies in the horse

Abstract

SummaryTo evaluate a novel tendon biopsy technique for use in the horse and to assess the effect of different exercise levels on the healing process of minimally damaged superficial digital flexor tendons (SDFT), 24 Dutch Warmblood foals were randomly divided into 3 equally sized groups one week after birth. One group was box rested, one group got box rest with additional enforced exercise, and one group got free pasture exercise. Biopsies from the peripheral region of the SDFT were taken at age 2 months using a new micro-biopsy technique. At age 5 months the foals were euthanized and samples from the biopsy site and a control site were harvested. Collagen fibrillar index (CFI, the total amount of collagen as a percentage of the measured area), mass-average diameter (MAvD, mean of the diameter versus area distribution) and collagen fibrillar diameter frequency (the distribution of collagen fibril sizes expressed as a percentage of the number of collagen fibrils) were calculated. The CFI, MAvD values were significantly lower in the wound samples. It is concluded that the biopsy technique may be a useful tool for research applications. The absence of exercise-induced effects on the collagen fibril population in the wound samples suggests that the first phase of the process of tendon healing in immature equine SDFT’s sustaining a minor surgically-induced wound, is not exercise-dependent. However, findings may be different in mature horses sustaining accidental trauma.A novel technique to take biopsies from immature equine flexor tendons was developed and used to evaluate the effect of various levels of exercise on the development of the collagen fibril diameter distribution in the resulting wounds. The technique appeared to be minimally invasive, but complication rate was deemed too high for clinical use. There was no effect of exercise on mass average diameter of collagen fibrils, suggesting that the repair process, at least in its initial stage, is exercise-independent.

Tendon Injuries

“…Patients often report an insidious onset of symptoms and a dull anterior knee pain. Many ultrasonographic studies have been performed [132][133][134][135][136][137][138][139][140][141][142], and MRI can also be a useful diagnostic tool. It is most distinct in full knee extension, and may be decreased in knee flexion [42].…”

Rehabilitation After Tendon Injuries

“…This runs counter to our experience that careful attention to the level of pain is crucial for improvement. We have found that a high level of pain, or pain too early in the program (before 20 repetitions) can cause a worsening of symptoms, while no pain during exercise results in patient stasis [142,172] (see also . Whether this careful attention to pain is really necessary requires further examination.…”

“…The response, even if it is primarily in the tendon sheath, somehow reflects the structural damage to the tendon, but the exact relationship is not yet known. The recent development of biopsy techniques for use in human and equine subjects seems a promising avenue for obtaining more accurate information about injured tendons [141,142].…”

“…The time course of recovery (complete recovery or marked relief of symptoms and return to full activity) for 200 patients using the eccentric exercise program. Most people spent less than 6 weeks on the program, a few spent more than 8 weeks[142]. Patient response to the eccentric exercise program.…”

“…Patient response to the eccentric exercise program. Shows the percentage of 200 patients with Achilles tendinopathy, patellar tendinopathy or lateral epicondylitis who experienced complete relief or marked relief (full function, minimal pain) of symptoms after 6 weeks on the eccentric exercise program[142].…”