Spondylolysis is known to be a part of a disease process, which describes a defect in the pars interarticularis
Developmental defect in pars interarticularis
, articulation between the upper and lower vertebrae in lower lumbar spine, can be seen approximately in 5% of young adults.
spondyloptosis) Etiologic (Wiltse (3)) classification * Type 1: Dysplastic Congenital defect of the neural arch * Type 2: Isthmic Pars interarticularis
defect (3 subtypes) a) Stress (fatigue) fracture (most common type, present in this case) b) Elongated pars c) Acute pars fracture * Type 3: Degenerative Facet joint osteoarthrosis * Type 4: Traumatic Acute fracture of the vertebral arch other than the pars * Type 5: Pathological Insufficiency fracture as a result of bone weakening diseases * Type 6: Iatrogenic Fracture secondary to spinal surgery such as laminectomy Table 2.
5 In Spondylolisthesis there are bilateral fractures in the pars interarticularis
of the spine and severe tightness is present in hamstrings group.
X-ray of the lumbosacral spine revealed reduced intervertebral disc space at LV4/ LV5 and LV5/SV1 levels and grade-I spondylolisthesis at LV5/SV1 level with defect in pars interarticularis
of LV5 (figure 3).
Plain anterior-posterior and lateral roentgenograms document the amount of vertebral subluxation, they also reveal a pars interarticularis
defect if one is present; oblique views have been used to highlight the Scottish Terrier-dog sign.
11] The reason for this is the inherent, high-load biomechanical nature of the bowling action[9,12] which may place undue stress on the pars interarticularis
during the delivery stride due to large contralateral lumbar side-flexion motion coupled with large ground reaction forces.
A spondylotic or isthmic defect is the term used to describe a radiolucent gap within the pars interarticularis
with sclerosis of the adjacent bone edges.
In the studies carried on the pathomechanism of spondylolytic spondylolisthesis , a thin pars model was created by removing half of the elements on one surface of the pars to see the effects of a thin pars interarticularis
on lysis and olistheis.
Histomorphic analysis of the development of the pars interarticularis
and its association with isthmic spondylolysis.
Essentially, a spondylolysis is a defect in the pars interarticularis
, an area of the vertebrae that connects the vertebral facets, or joints that adjoin vertebrae together.
Based on the patient's progressive pain pattern and lack of recovery after 2 weeks rest, a pars interarticularis
stress fracture was suspected clinically.