Degenerative Joint Disease (DJD) Notes

DJD: Degenerative Joint Disease

  • Most common type of arthritis seen in practice.
  • Also known as:
    • Osteoarthritis (OA)
    • Degenerative Disc Disease (DDD) - when occurring at the disc vertebral joints.
    • Discogenic Spondylosis.

Understanding DJD and DDD

  • DJD is an umbrella term for degenerative arthritic disorders.
  • DDD: Specific to the disc vertebral joint.
  • Osteoarthritis: Occurs outside the disc vertebral joint (e.g., facets, ADI space).

Clinical Features

  • Pain
  • Stiffness
  • Crepitus
  • Deformity
  • Swelling

Radiographic Diagnosis

  • Radiographs are crucial for diagnosis.
  • Clinical features are common to many arthritides.
  • Lab results are typically normal.
  • Diagnosis is primarily based on radiographic findings.
  • Most common sites: Weight-bearing articulations (hips, spine, knees), first metatarsophalangeal joint, first metacarpal-trapezium joint, and DIPs.

Radiographic Hallmarks (LEO)

  • Loss of Joint Space (LJS): Must be present for diagnosis, is typically nonuniform (one side more affected).
  • Eburnation
  • Osteophytes
  • Asymmetrical presentation: One side of the body is usually affected first.
  • Subchondral cysts (Geodes): May or may not be present.
  • Intra-articular loose bodies (Joint Mice): May or may not be present.
  • Intra-articular deformities: May occur in later stages.

Vacuum Sign (Knudsen Sign)

  • Pathognomonic for DJD/DDD.
  • Radiolucency found in the disc space.
  • Thought to be a collection of nitrogen gases.
  • Appears as linear lucencies within the disc space.

Complications of DDD

  • Subluxation: Joint may subluxate medically due to degenerative changes.

Gull Sign

  • Seen in hands of osteoarthritis patients.
  • Osteoarthritis of the hand targets DIPs and PIPs.
    • Metacarpophalangeal joints (MCPs) are typically clear.
  • Gull sign: Biconcave endplates at DIPs and/or PIPs.

OA of the Hand

  • Targets DIPs and PIPs.
  • Causes loss of joint space, eburnation, and osteophyte formation leading to the gull sign.
  • Heberden's nodes (DIPs) and Bouchard's nodes (PIPs).

DJD Radiographic Signs (Recap)

  • Nonuniform loss of joint space.
  • Eburnation.
  • Osteophyte formation (must be present).
  • Possible subchondral cysts (geodes).
  • Possible intra-articular loose bodies (joint mice).
  • Possible joint subluxation and deformity (late stages).

Radiographic Examples

  • Hip Joint: Superior joint space should be 4mm, medial 8mm. Loss of superior joint space and osteophyte formation indicate OA.
  • Knee: Progression from simple loss of joint space to osteophytes and misalignment.

Weight-Bearing Radiographs

  • Extremity views should be taken in an upright position to assess weight-bearing effects.
  • Medical offices often take films in a recumbent position, missing these effects.

Loose Bodies

  • Can be found in the suprapatellar pouch or retropatellar space.
  • Patellofemoral joint: Loss of joint space, eburnation, large osteophytes, and loose bodies.

Vacuum Sign Example

  • L5-S1 joint: Loss of joint space, eburnation, osteophyte formation, and vacuum sign (Knudsen sign).
  • Severe DDD can be diagnosed based on these findings.

Provocation

  • Vacuum sign may be more apparent on flexion/extension views due to stress on the joint.

Disc Desiccation

  • Discs lose integrity and hydration.
  • MRI can show loss of normal disc physiology.

Clinical Considerations

  • Don't overlook DDD of the spine.
  • Adjustments can be performed with DDD, but assess risk vs. reward in severe cases.
  • Severe degeneration may contraindicate adjustments due to IVF involvement.
  • Consider least invasive procedures first before referral for surgery.

Osteoarthritis in Hands

  • Targets DIPs and PIPs, spares MCPs.
  • MCPs remain clean (no erosions, osteophytes, or subchondral sclerosis).