What is the definition of the medical prefix "myelo-"?

Definition of "Myelo-"

The medical prefix "myelo-" refers to two distinct anatomical structures: bone marrow or the spinal cord, depending on the clinical context. 1

Primary Meanings

Bone Marrow Context

• "Myelo-" most commonly denotes bone marrow and the hematopoietic (blood-forming) cells that reside within it 1
• This usage appears in terms such as:
  • Myeloma: A malignancy characterized by proliferation of plasma cells in the bone marrow 1, 2
  • Myeloid: Referring to nonlymphoid hematopoietic cells originating from bone marrow, including granulocytes, monocytes, erythrocytes, and megakaryocytes 1
  • Myeloproliferative disease: Disorders involving increased production of bone marrow-derived cells 1
  • Myelodysplasia: Abnormal development or maturation of bone marrow cells 1

Spinal Cord Context

• "Myelo-" also refers to the spinal cord in neurological terminology 1
• This usage appears in:
  • Myelopathy: Any pathologic process affecting the spinal cord, presenting with signs and symptoms of spinal cord dysfunction 1
  • Myelography: Imaging of the spinal cord using contrast material 1

Clinical Application

Distinguishing Context

• The specific meaning is determined by the complete medical term and clinical setting 1
• In hematology and oncology, "myelo-" invariably refers to bone marrow 1, 2
• In neurology and spine surgery, "myelo-" refers to the spinal cord 1

Common Pitfalls

• Do not confuse myeloma (bone marrow plasma cell malignancy) with myelopathy (spinal cord disease), as these represent entirely different disease processes despite sharing the same prefix 1, 2
• Multiple myeloma involves bone marrow infiltration by malignant plasma cells and frequently causes bone destruction, but when it produces neurologic symptoms through spinal involvement, this represents a complication of the bone disease rather than primary spinal cord pathology 3, 4