What is paraplegia?

Definition of Paraplegia

Paraplegia refers to complete paralysis (total loss of voluntary motor function) of the lower limbs, typically resulting from spinal cord injury or disease affecting segments below the cervical level. 1

Terminology Clarification

• The prefix "para" specifically refers to the lower limbs, while the suffix "plegia" indicates complete paralysis of the affected body parts 1, 2
• Paraparesis is the correct term for partial paralysis (weakness) of the lower limbs, not to be confused with incomplete paraplegia 3
• The distinction is important: patients with any preservation of motor strength below the injury level should be described as paraparetic, not as incomplete paraplegic 3
• Other related terms include:
  • Tetraplegia (formerly quadriplegia): complete paralysis of all four limbs 1, 2
  • Hemiplegia: paralysis of one side of the body 1
  • Monoplegia: paralysis of a single limb 2

Anatomical Basis

• Paraplegia typically results from spinal cord lesions caudal to the second thoracic spinal cord segment (T2) 2
• According to spinal cord segmental control of key muscles:
  • Complete injuries at C1-C5 typically result in tetraplegia 1
  • Injuries at C6-T1 present with paraplegia and brachial diparesis 1
  • Injuries at T2-L2 result in classic paraplegia 1
  • Injuries at L3-S1 typically cause paraparesis 1

Common Causes

• Traumatic spinal cord injury is a leading cause of paraplegia 4
• Vascular causes include spinal cord ischemia following thoracic aortic surgery (2-6% incidence) 5
• Malignant spinal cord compression can cause paraplegia, with symptoms including pain, paralysis, sensory loss, and sphincter dysfunction 4
• Infectious and inflammatory causes like schistosomiasis can result in myelitis with gradual onset paraplegia 4

Clinical Implications

• Paraplegia significantly impacts quality of life and survival rates 4, 5
• Patients with paraplegia rely heavily on their upper extremities for mobility and transfers, leading to high rates (67.8%) of upper extremity pain and complications over time 6
• Recovery potential depends on injury level and completeness:
  • Patients with complete injuries above T9 rarely regain lower extremity motor function 7
  • Approximately 38% of patients with complete injuries at or below T9 may regain some lower extremity motor function 7
  • About 20% of patients with injuries at or below T12 may regain sufficient strength to ambulate with orthoses and crutches 7
• Late conversion from complete to incomplete injury occurs in approximately 4% of cases, sometimes allowing for functional recovery 7

Management Considerations

• Cerebrospinal fluid drainage is recommended as a primary protective strategy in patients at risk of spinal cord ischemic injury during thoracic aortic repair 4, 5
• Maintaining adequate spinal cord perfusion pressure through blood pressure management is critical 5
• Surgical decompression is recommended for spinal cord compression from tumors or other mass lesions 5
• Prevention of secondary complications includes management of neurogenic bladder and bowel dysfunction 5