Understanding Medical Terminology: A Patient's Guide to Your Diagnosis

Medical terminology can feel like a foreign language. When your doctor says you have "supraspinatus tendinopathy with partial-thickness tearing" or your MRI shows "moderate degenerative disc disease with neural foraminal stenosis," understanding what that means helps you participate in your care.

This guide decodes common medical terms for musculoskeletal conditions.

How Medical Terms Are Built

The Logic of Medical Language

Most medical terms are built from Greek and Latin roots. Once you understand the building blocks, you can decode unfamiliar terms.

Structure: Prefix + Root + Suffix

Example: Tendinopathy

• Tendin- (root) = tendon
• -pathy (suffix) = disease/disorder
• Meaning: disorder of a tendon

Common Prefixes

Location/Position:

• Sub- = below (subcutaneous = below skin)
• Supra- = above (supraspinatus = above the spine of scapula)
• Infra- = below (infraspinatus = below the spine of scapula)
• Inter- = between (intervertebral = between vertebrae)
• Intra- = within (intra-articular = within joint)
• Peri- = around (periosteum = around bone)
• Para- = beside (paraspinal = beside spine)
• Epi- = upon (epicondyle = upon the condyle)

Size/Degree:

• Hyper- = excessive (hypertrophy = excessive growth)
• Hypo- = deficient (hypomobility = decreased movement)
• Macro- = large
• Micro- = small

Number:

• Uni-/Mono- = one (unilateral = one side)
• Bi- = two (bilateral = both sides)
• Poly-/Multi- = many (polyarthritis = many joints)

Direction:

• Ab- = away from (abduction = movement away from midline)
• Ad- = toward (adduction = movement toward midline)
• Retro- = backward (retrolisthesis = backward slippage)
• Ante- = forward (anteversion = forward tilting)

Common Roots

Body Tissues:

• Arthr- = joint (arthritis, arthroscopy)
• Oste- = bone (osteoporosis, osteophyte)
• Chondr- = cartilage (chondromalacia, chondrocyte)
• My-/Myo- = muscle (myopathy, myofascial)
• Tend-/Tendin- = tendon (tendinitis, tendinopathy)
• Ligament- = ligament
• Burs- = bursa (bursitis)
• Neur- = nerve (neuralgia, neuropathy)
• Vas-/Vascul- = blood vessel (avascular, vascular)

Spine:

• Vertebr- = vertebra (vertebral)
• Spin- = spine (spinal)
• Cerv-/Cervic- = neck (cervical spine)
• Thorac- = chest/mid-back (thoracic spine)
• Lumb- = lower back (lumbar spine)
• Sacr- = sacrum
• Disc- = disc (discectomy)

Extremities:

• Brachi- = arm (brachial plexus)
• Humer- = upper arm bone (humerus)
• Radi- = radius/forearm bone
• Uln- = ulna/forearm bone
• Carp- = wrist (carpal tunnel)
• Metacarp- = hand bones
• Phalang- = finger/toe bones
• Femor- = thigh bone (femoral)
• Patell- = kneecap (patellar)
• Tibi- = shin bone (tibial)
• Fibul- = smaller leg bone
• Tars- = ankle (tarsal)
• Metatars- = foot bones
• Calcan- = heel bone

Common Suffixes

Conditions:

• -itis = inflammation (tendinitis, bursitis)
• -osis = condition/disease (stenosis, arthrosis)
• -pathy = disease/disorder (tendinopathy, neuropathy)
• -algia = pain (neuralgia, myalgia)
• -dynia = pain (pleurodynia)
• -emia = blood condition
• -malacia = softening (chondromalacia = cartilage softening)
• -sclerosis = hardening (arteriosclerosis)
• -trophy = growth/development (atrophy = wasting, hypertrophy = overgrowth)

Procedures:

• -ectomy = surgical removal (meniscectomy = meniscus removal)
• -otomy = surgical cutting (osteotomy = bone cutting)
• -plasty = surgical repair (arthroplasty = joint repair/replacement)
• -scopy = looking inside (arthroscopy = looking in joint)
• -graphy = imaging (radiography = X-ray imaging)
• -gram = record/image (arthrogram = joint image)
• -centesis = puncture to drain (arthrocentesis = joint drainage)

Descriptions:

• -ic/-al = pertaining to (articular = pertaining to joint)
• -oid = resembling (rheumatoid = resembling rheumatism)
• -genic = causing (pathogenic = disease-causing)

Common Diagnostic Terms

Describing Severity

Grade/Stage:

• Grade I = mild
• Grade II = moderate
• Grade III = severe
• Grade IV = most severe (some systems)

Descriptors:

• Mild = minimal changes/symptoms
• Moderate = noticeable but not severe
• Severe = significant/advanced
• Acute = sudden onset, short duration
• Chronic = long-lasting (usually 3+ months)
• Subacute = between acute and chronic

Tissue Damage Terms

Tears:

• Partial-thickness = incomplete tear (doesn't go all the way through)
• Full-thickness = complete tear (goes through entire structure)
• Complete tear with retraction = ends have pulled apart
• High-grade partial = nearly complete tear
• Low-grade partial = minor partial tear

Degeneration:

• Degenerative = wear and tear changes
• Degenerative disc disease (DDD) = disc wearing down (common, often not "disease")
• Osteoarthritis (OA) = joint wear and tear
• Chondromalacia = cartilage softening

Inflammation vs. Degeneration:

• -itis traditionally means inflammation
• -osis or -pathy suggests degeneration without acute inflammation
• Example: Tendinitis (inflamed) vs. Tendinosis/Tendinopathy (degenerative)

Spine-Specific Terms

Disc Terms:

• Bulging disc = disc extends beyond vertebral borders (very common, often normal)
• Herniated disc = disc material pushes outward more significantly
• Protrusion = herniation with narrow base
• Extrusion = herniation with narrow neck
• Sequestered = fragment broken off from disc
• Desiccation = disc drying out (normal aging)

Space Terms:

• Stenosis = narrowing (spinal stenosis = narrowed spinal canal)
• Foraminal stenosis = narrowed nerve exit holes
• Central stenosis = narrowed central canal

Position Terms:

• Spondylolisthesis = vertebra slipped forward
• Retrolisthesis = vertebra slipped backward
• Subluxation = partial dislocation

Bone Terms:

• Osteophyte = bone spur
• Spondylosis = spine arthritis/degeneration
• Spondylolysis = crack in vertebra (pars defect)

Joint Terms

Arthritis Types:

• Osteoarthritis = wear and tear arthritis
• Rheumatoid arthritis = autoimmune arthritis
• Inflammatory arthritis = arthritis with active inflammation
• Post-traumatic arthritis = arthritis from prior injury

Cartilage Terms:

• Chondral = relating to cartilage
• Chondral defect = cartilage damage
• Osteochondral = involving bone and cartilage

Joint Fluid:

• Effusion = fluid in joint (swelling)
• Hemarthrosis = blood in joint
• Synovitis = inflammation of joint lining

Soft Tissue Terms

Tendon:

• Tendinopathy = tendon disorder
• Tendinosis = chronic tendon degeneration
• Tendinitis = tendon inflammation
• Tenosynovitis = inflammation of tendon sheath
• Peritendinitis = inflammation around tendon
• Enthesopathy = disorder where tendon attaches to bone

Muscle:

• Strain = muscle or tendon injury
• Myopathy = muscle disease
• Myofascial = relating to muscle and fascia
• Atrophy = muscle wasting
• Contracture = muscle shortening

Ligament:

• Sprain = ligament injury
• Laxity = looseness
• Instability = excessive movement

Bursa:

• Bursitis = inflamed bursa

Nerve Terms

Nerve Problems:

• Neuropathy = nerve disorder
• Radiculopathy = nerve root problem (pinched nerve)
• Neuralgia = nerve pain
• Paresthesia = abnormal sensation (tingling, pins and needles)
• Dysesthesia = unpleasant abnormal sensation
• Hyperesthesia = increased sensitivity
• Hypoesthesia = decreased sensation
• Anesthesia = absent sensation

Nerve Compression:

• Compression = pressure on nerve
• Impingement = something pressing on structure
• Entrapment = nerve trapped by surrounding tissue

Imaging Report Terms

What Radiologists See:

• Signal change = abnormal appearance on MRI (could be many things)
• Edema = swelling/fluid in tissues
• Enhancement = area lights up with contrast (indicates blood flow/inflammation)
• Lesion = general term for abnormality
• Mass = something taking up space (not necessarily cancer)
• Cyst = fluid-filled sac

Severity Descriptors:

• Mild/Moderate/Severe = degrees of finding
• Minimal = very slight
• Significant = notable
• Unremarkable = normal
• Within normal limits = normal
• Age-appropriate changes = normal for your age

Understanding Your Diagnosis

Breaking Down Diagnoses

Example 1: "Right supraspinatus tendinopathy with partial-thickness tearing"

• Right = right side
• Supraspinatus = name of rotator cuff muscle/tendon
• Tendinopathy = tendon disorder
• Partial-thickness tearing = incomplete tear

Plain English: Partial damage to one of your rotator cuff tendons

Example 2: "L4-5 disc herniation with left-sided foraminal stenosis and L5 radiculopathy"

• L4-5 = between 4th and 5th lumbar vertebrae
• Disc herniation = disc bulging/protruding
• Left-sided = on the left
• Foraminal stenosis = narrowing of nerve exit hole
• L5 radiculopathy = L5 nerve being affected

Plain English: Disc pushing on a nerve in your lower back

Example 3: "Moderate medial compartment osteoarthritis with grade 3 chondral changes"

• Moderate = middle severity
• Medial compartment = inner part of knee
• Osteoarthritis = wear and tear arthritis
• Grade 3 = significant severity
• Chondral changes = cartilage damage

Plain English: Significant wear and tear arthritis on the inner part of your knee

Questions to Ask

If you don't understand:

1. "Can you explain what that means in plain language?"
2. "What does that term actually mean?"
3. "Is this serious or is it common?"
4. "How does this affect my treatment?"
5. "Can I get a copy of the report to review?"

What Findings Mean (and Don't Mean)

Findings Don't Equal Symptoms

Important: Many imaging findings are common in people WITHOUT symptoms.

Disc "abnormalities" in pain-free people:

• Age 20: ~30% have disc bulges
• Age 50: ~80% have disc degeneration
• Age 70: ~90% have disc changes

Rotator cuff findings in pain-free people:

• Age 50+: ~50% have some rotator cuff changes
• Age 70+: ~70% have rotator cuff abnormalities

Knee findings in pain-free people:

• Meniscus tears common in asymptomatic adults
• Cartilage changes normal with age

Bottom line: Findings on imaging don't necessarily explain your pain. Clinical correlation is essential.

"Degenerative Changes"

This term appears frequently and often causes concern.

What it means: Normal wear and tear changes from use and aging.

What it doesn't mean: Disease, damage requiring treatment, or serious problem.

Like gray hair: Degenerative changes are expected with age. Their presence doesn't mean they cause pain.

Conclusion

Medical terminology follows logical patterns. Once you understand the building blocks—prefixes, roots, and suffixes—you can decode most terms you encounter.

Don't hesitate to ask your providers to explain terms in plain language. Understanding your diagnosis empowers you to participate in treatment decisions.

Remember: imaging findings and diagnostic labels describe anatomy, not necessarily pain or prognosis. Many "abnormal" findings are actually normal for your age and don't require treatment.

You deserve to understand what's happening in your body. Use this guide as a reference, and always ask questions when terminology is unclear.