Carlos Pineda

1
1983-1984

• Carlos Pineda
• Roger Kerr

2
Roger Kerr, Los Angeles, CA

• 49 year old male with 6 month history of wrist
  pain and swelling.
• Past medical history is negative.
• PE exquisite tenderness over distal ulna with
  loss of extension of 4th and 5th fingers.
• Routine laboratory studies are negative.

3
49 year old male with 6 month history of wrist
pain and swelling.
PA view of wrist Enlargement of ulnar styloid
with lytic/erosive change and soft tissue
swelling.
4
49 year old male with 6 month history of wrist
pain and swelling.
Coronal T1-weighted image intermediate signal
intensity mass surrounds and engulfs ECU tendon
with erosion of distal ulna.
5
49 year old male with 6 month history of wrist
pain and swelling.
Sagittal T1-weighted image intermediate signal
intensity mass surrounds and infiltrates ECU
tendon.
6
49 year old male with 6 month history of wrist
pain and swelling.
Consecutive axial T1-weighted images at level of
ulnar styloid ECU tendon is replaced by
predominantly intermediate signal intensity mass
that erodes distal ulna.
7
49 year old male with 6 month history of wrist
pain and swelling.
Axial T1-weighted and axial T2-weighted images,
respectively, at level of tip of ulnar styloid
mass of predominantly intermediate signal
intensity has replaced ECU tendon and erodes ulna.
8
49 year old male with 6 month history of wrist
pain and swelling.

• Bone scan revealed increased uptake of
  radionuclide at both 1st MTP joints, ankles and
  knees and at left midfoot and left shoulder.

9
Differential diagnosis

• Tophaceous gout
• Tendon sheath lesions giant cell tumor, fibroma
  , xanthoma
• Tuberculous tenosynovitis
• Rheumatoid arthritis with fibrous pannus
• Amyloidosis
• Clear cell sarcoma

10
Dx Tophaceous gout of tendon

• At surgery ECU and EDC (4th,5th) tendons were
  debrided of chalky material and crystalline
  deposits.
• Histology crystals with strong negative
  birefringence, dense fibrous connective tissue
  and mild chronic synovitis.

11
Dx Tophaceous gout of tendon

• Gout of tendon usually in patient with
  established diagnosis of gout. Tendon
  infiltration, tenosynovitis, tendon rupture,
  entrapment neuropathy. Often mis-diagnosed
  clinically as tumor or tumor-like lesion.
• Gout usually heterogeneous intermediate to low
  signal intensity on T2-weighted images related to
  fibrous tissue and urate crystals. Intense
  gadolinium enhancement.

12
Roger Kerr, Los Angeles, CA

• 5 year old male presents with a 2 day history of
  pain and swelling of left knee.
• Vague history of knee pain 4 weeks ago treated
  with NSAIDS.
• No history of trauma or recent infection.
• No other joint problems.
• WBC9.4 ESR44 Febrile (up to 102)

13
5 year old male presents with a 2 day history of
pain and swelling of left knee.
Lateral radiograph of the knee
14
5 year old male presents with a 2 day history of
pain and swelling of left knee.
AP radiograph of the knee
15
A
B
5 year old male presents with a 2 day history of
pain and swelling of left knee.
Immediate (A) and delayed (B) 99mTcMDP images
were interpreted as consistent with septic
arthritis with no evidence of osteomyelitis.
16
5 year old male presents with a 2 day history of
pain and swelling of left knee.

• Joint aspiration yielded cloudy fluid with 80,000
  WBC/mm3 (99 PMNs) and 100,000 RBC/mm3.
• Arthroscopic drainage and debridement of the
  joint was performed on the third hospital day.
• Patient was treated with IV antibiotic
  (Ceftazidine, then Vancomycin) but knee swelling
  and pain and fever persisted. On day 10, an MRI
  was obtained.

17
5 year old male presents with a 2 day history of
pain and swelling of left knee.
A sagittal T2-weighted image reveals a large
joint effusion, synovial hypertrophy,
intra-articular debris and a large high signal
intensity lesion of the patella c/w septic
arthritis and osteomyelitis/bone abscess.
18
5 year old male presents with a 2 day history of
pain and swelling of left knee.
B
B
A
Successive axial intermediate-weighted images
reveal extension of this lesion through the
anterior cortex of the patella.
C
19
Diagnosis septic arthritis of the knee and
osteomyelitis/bone abscess of the patella

• Incision and drainage of the patella was
  performed and purulent fluid was removed.
• Histology revealed acute and chronic inflammation
  and Staph aureus was cultured.
• The patient recovered following a course of IV,
  followed by oral, antibiotics.

20
Osteomyelitis of the patella

• Rare usually due to direct implantation from a
  break in the skin, puncture wound, septic
  bursitis or septic arthritis.
• Hematogenous spread to patella is exceedingly
  rare rich blood supply and no physeal plate with
  its sluggish hemodynamics.
• Acute or insidious onset.
• Local signs or symptoms vs. systemic illness.
• Diagnosis is often delayed or overlooked as
  clinician assumes patient only has joint, bursal
  or soft tissue infection.

21
Osteomyelitis of the patella

• Clue to diagnosis pt. not responding to standard
  management of septic arthritis.
• Surgical debridement indicted for
  subperiosteal/bone abscess or chronic
  osteomyelitis.
• In this patient, radiographs and bone scan were
  negative for osteomyelitis due to immaturity of
  patellar development. MRI was definitive.
• Roy DR et al Osteomyelitis of the patella in
  children. J Ped Orthop 199111364-366.