Grade 1 spondylolisthesis without instability on flexion/extension and claudication

Introduction

Spondylolisthesis was first described by Herbiniaux, who noted the presence of a lumbar vertebrae ventral to the sacrum causing an obstruction to the progression of labor during a routine pelvic exam. The term “spondylolisthesis,” however, was not used until Kilian reported the cause of this condition due to the subluxation of the facet joint. Lumbar spondylolisthesis is described as ventral subluxation of one vertebrae body on the other. It is classified as either congenital/dysplastic, isthmic, degenerative traumatic, or pathological based on the classification of Wiltse-Newman-MacNab, which has become the most widely accepted classification system. The degree of slippage is graded based on the Meyerding, where the scale varies from grade I to V ( Table 1.1 ). Grade I spondylolisthesis is defined as slippage less than 25%, grade II is displacement up to 50%, grade III is displacement up to 75%, grade IV is displacement greater that 75%, and grade V is defined as a complete subluxation of one body on another and is also referred to as spondyloptosis.

Example case

Chief complaint: leg and back pain

History of present illness: A 77-year-old male with a history of back and leg pain for multiple years. Over the last few months, he has had worsening back pain that radiates to his buttocks and lower extremities. He also has some numbness down his lower extremities. He can stand for an extended period time but is only able to walk around 100 yards. He has tried physical therapy without significant improvement. He also underwent an epidural injection, which gave him 1 week of relief ( Fig. 1.1 ).

Medications: losartan, aspirin 81 mg, amlodipine, tamsulosin, simvastatin

Allergies: penicillin

Past medical and surgical history: hypertension, prostate cancer status post prostatectomy, umbilical hernia repair

Family history: noncontributory

Social history: retired engineer, no smoking history, occasional alcohol

Physical exam: Awake, alert, and oriented to person, place, and time; cranial nerves II–XII intact; bilateral deltoids/triceps/biceps 5/5; interossei 5/5; iliopsoas/knee flexion/knee extension/dorsi; and plantar flexion 5/5

Reflexes: 2+ in bilateral biceps/triceps/brachioradialis with negative Hoffman; 2+ in bilateral patella/ankle and no clonus or Babinski; sensation is intact to light touch

The different types of spondylolisthesis include the following ( Table 1.2 ):

• Congenital/dysplastic is a result of malformed facet joints. It predominately occurs in the lumbosacral junction. A malformed inferior facet joint may lead to enlongation of the facet joint, ultimately leading to a pars defect. Due to this congenital nature, it is commonly associated with spina bifida.

• Isthmic is the most common form of spondylolisthesis and results from a defect of the pars interarticularis. This subtype is a result of repeated microfracture and remodeling of the pars. This is most common in young athletes who participate in high-impact sports.

• Degenerative results from degeneration of the facet joint. Degeneration of the joint space causes abnormal motion. The remodeling that occurs as a result of degeneration causes a more sagittal alignment of the facet, which allows progression of the spondylolisthesis. This type is typically associated with both foraminal and canal stenosis.

• Traumatic is the result of a fracture that typically does not involve the pars. Over time, slippage of the vertebral body occurs following the injury. This is unique in that healing can occur from simple immobilization. Fractures that are associated with an acute slippage are defined as a fracture dislocation and should be treated accordingly.

• Pathological are grouped into two types: generalized and local. Generalized spondylolisthesis is caused by diseases such as Paget disease, hyperthyroidism, osteoporosis, and syphilitic changes. The localized subtype is due to local destruction from tumors and infection. Iatrogenic cause of pathological spondylolisthesis can also be classified as localized spondylolisthesis, although some authors have classified this as its own entity.