Abstract
Objective This article aims to report the medium-term clinical outcome and assess persistence
of enlargement of the lumbosacral lateral intervertebral neurovascular foramen using
computed tomography (CT) volumetric analysis in dogs following lateral foraminotomy.
Materials Six dogs that underwent lumbosacral lateral foraminotomy on one or both sides were
evaluated with CT prior to, immediately postoperatively (n = 2) and at 12 to 44 months of follow-up. Five out of six dogs had successful clinical
outcomes with alleviation of pain and increased levels of activity, according to subjective
assessment. Immediate postoperative CT volumetric analysis of the lateral intervertebral
neurovascular foramina in two dogs indicated a 650 to 800% increase in volume in extension
achieved by foraminotomy (four foramens). At subsequent follow-up, bone regrowth had
occurred with reduction in foraminal volume, though in both dogs foraminal volume
remained higher than preoperative values. Follow-up CT at a median of 24 months postoperatively
indicated a mean 335% increase in volume of the lumbosacral lateral intervertebral
neurovascular foramina in extension compared with the preoperative foraminal volume.
The follow-up volume was substantially greater than the presurgical volume in four
out of six dogs.
Clinical Significance In this limited case series, lateral foraminotomy achieved persistent enlargement
of the lumbosacral lateral intervertebral neurovascular foramen in the medium term,
but osseous regrowth at the site was demonstrated which may limit the effectiveness
of lateral foraminotomy in the longer term. One of two working dogs had recurrent
clinical signs that necessitated further surgery.
Keywords
lumbosacral - cauda equine - foraminotomy - foraminal volume - bone modelling
