Plantar fasciotomy and neurectomy for DSLD

Hindlimb proximal suspensory desmopathy (desmitis) is a frequent problem with sport horses and some breeds are genetically predisposed to the problem. Plantar fasciotomy and neurectomy offer the best prognosis for the chronic condition. It has been recommended that following the proximal ligament cross-sectional area (CSA) might be a good way to follow improvement following surgery. This paper found that, at least for a year out, there was not any change in size using ultrasound to follow changes. However, the horses so treated had a good prognosis for returning to work. Longer studies are needed to see the long-term effects of working a horse of a de-nerved damaged suspensory ligament.

Suspensory ligament size does not change after plantar fasciotomy and neurectomy of the deep branch of the lateral plantar nerve by ultrasonographic assessment
Vet Surg. 2021 Dec 31. doi: 10.1111/vsu.13757. Online ahead of print.
Authors
Alexandra Scharf 1 , Cristobal Navas de Solis 1 , Sarah N Sampson 1 , Kati Glass 1 , Ashlee E Watts 1
Affiliation

1 Department of Large Animal Clinical Sciences, Texas A&M University, College Station, Texas, USA.

PMID: 34970755
DOI: 10.1111/vsu.13757

Abstract

Objective: To determine the short-term effect of plantar fasciotomy and neurectomy (PFN) of the deep branch of the lateral plantar nerve on the proximal suspensory ligament (PSL) cross-sectional area (CSA) in horses with hindlimb proximal suspensory desmopathy (PSD).

Study design: Analytical, observational, cohort study.

Sample population: Twenty-one horses.

Methods: Records of horses with chronic PSD treated by PFN were included if a preoperative ultrasonographic examination was available and at least one postoperative ultrasonographic examination. One masked observer measured the ultrasonographic cross-sectional area (CSA) of the PSL. Intraobserver reliability was determined by repeatedly measuring a subset of ultrasonographic images (n = 127). Two masked observers measured the cross-sectional area of the proximal suspensory ligament (PSL-CSA) on preoperative proton density (PD)-weighted transverse high field magnetic resonance images (n = 19 horses) . Agreements for PSL-CSA between preoperative ultrasonographic and MRI measures and between the two magnetic resonance imaging (MRI) observers were assessed. Follow up considered the horses’ ability to return to exercise and their owners’ satisfaction.

Results: The reliability of the ultrasonographic measurement of the PSL-CSA was excellent. Agreement between ultrasonographic assessment and MRI assessment of PSL-CSA was good. No difference was detected between preoperative (median, interquartile range; oblique-incidence, 2.07, 1.72-2.55; on-incidence, 2.23, 1.98-2.65) and postoperative (oblique-incidence, 2.08, 1.80-2.74; on-incidence, 2.28, 2.01-2.74) PSL-CSAs. At a median of 12 months (4-33 months), 16/20 (80%) owners reported the horse was “better” and 15/20 (75%) functioned at or above preoperative levels.

Conclusion: Ultrasonographic measurement of the PSL-CSA was reproducible and in good agreement with MRI measurement. The PSL-CSA was not influenced by PFN.

Clinical significance: The PSL-CSA cannot be used to guide return to function.