‘Slipped’ disc or Herniated Lumbar disc is defined as Central (Yellow), Posterolateral (White), Foraminal (Red) or Extraforaminal (Purple) depending upon the position of the prolapsed fragment, as shown in the depiction below.
Central zone (Yellow) is located within the vertebral canal between sagittal planes through the medial edges of each facet (White arrowheads) as shown in the picture below. One-third of all disc herniations occur in this zone.
Slipped Central disc can occur in the elderly or in young athletes. In the elderly, centrally located lumbar disc herniation results from annular tears facilitating a herniation of disc material, should sufficient forces be placed on the disc. In young athletes however, a large biomechanical force placed on a healthy, normal disc may lead to extrusion of disc material in the setting of catastrophic failure of the annular fibers.
A young man working as a manual laborer presented with sudden onset low back pain with sciatica radiating along the back of his thighs to the ankle with weakness, numbness in the legs retention of urine. This is the Acute Cauda Equina Syndrome presentation.
Magnetic Resonance Imaging of Lumbar spine clinched the diagnosis of a Herniated ‘Central’ Lumbar disc causing Cauda Equina compression.
The patient underwent surgery with removal of the extruded disc fragment with excellent recovery!
Centrally located lumbar disc herniations have been reported to be of predictive value for poor postoperative clinical outcome. This is particularly true of cases operated beyond 24 hours of onset of Acute Cauda Equina Syndrome symptoms.