-malacia
Meaning of -malacia: Tissue gone soft where it should be firm, a change visible on scans and under the microscope alike.
Definition of -malacia
The suffix -malacia means abnormal softening of the tissue the root names. Osteomalacia is softening of bone, chondromalacia of cartilage, tracheomalacia of the windpipe wall. The softened tissue loses the stiffness its job depends on, so a bone bends, a joint surface roughens, or an airway collapses inward at the moment it should be holding itself open.
What changes in the tissue?
Its structure rather than its amount. Firm tissues get their stiffness from something laid down within a flexible framework: mineral within bone, dense fibers within cartilage, rings of cartilage within an airway wall. When that stiffening element is missing, defective or worn away, the framework remains but goes slack. Bone still has its full protein scaffold of collagen and simply fails to harden it properly, which is why the bone bends and aches rather than snapping cleanly.
How does softening differ from thinning?
Sharply, and confusing the two is the usual mistake with this ending. Osteomalacia and osteoporosis both weaken bone and are entirely different problems. In osteomalacia the amount of bone is normal but poorly mineralized, so it is soft. In osteoporosis the bone present is normally mineralized but there is less of it, so it is brittle. The distinction shapes what the rest of the skeleton looks like on imaging and what blood tests show.
Where in the body does it appear?
| Term | Root | What softens |
|---|---|---|
| osteomalacia | oste, bone | poorly mineralized bone that aches and bends |
| chondromalacia | chondr, cartilage | joint cartilage, classically behind the kneecap |
| tracheomalacia | trache, windpipe | an airway wall that collapses on breathing |
| laryngomalacia | laryng, voice box | floppy tissue above the voice box in infants |
| encephalomalacia | encephal, brain | brain tissue softened after its blood supply failed |
The opposite change has its own ending. Sclerosis means hardening, so a tissue described as sclerotic has stiffened while one described with this ending has gone the other way. Both changes weaken a structure, because tissue works properly only at the stiffness it evolved to have, and a windpipe that has hardened obstructs airflow just as surely as one that has gone floppy.
Also known as
Used in a sentence
The suffix -malacia in the term indicated softening of the tissue rather than inflammation.
Good to know
Osteomalacia and osteoporosis both weaken bone by different means, since one describes bone of normal amount that is poorly mineralized and the other describes normally mineralized bone that is reduced in quantity.
Word origin
Where “-malacia” comes from
From the Greek malakia, meaning softness, from malakos, meaning soft; the opposite ending, -sclerosis, comes from skleros, meaning hard.