2.  17 yo otherwise healthy
male soccer player c/o
nagging pain to Left knee
for several months, with
occasional swelling. He
denies acute injury, stating
pain is usually worse when
exercising. Has begun to
walk with limp in order to
reduce pain. Denies fever,
rashes, dysuria and sexual
activity.
 AFVSS
 Gen: WDWN, A&Ox4
 Neuro: CNs 2-12 intact,
Nml 5/5 motor strength
and sensation x 4. Nml
reflexes.
 MSK: Pain and
crepitation on forcible
compression to medial
femoral epicondyle during
knee extension and
flexion. No effusion,
warmth, or erythema to
knee. Walks with LLE
slightly externally rotated.

4. Thin rim of calcium
separated from underlying
bone.
MRI showing subchondral defect in
medial femoral condyle

5.  Initial X-rays may have occult fx, often missed unless
advanced changes are present
 Tx is different in adults vs children:
 Adults: usually require surgery to prevent premature
degenerative arthritis
 Children: long-leg splint/Ortho referral, minimumweight bearing immobilization for minimum of 6 weeks
 If loose body fragment is present in joint space, arthroscopic
surgery recommended for all patients.
 NSAIDS for analgesia

6.  Separation of joint surface cartilage/subchondral bone from the
underlying bone
 MC in the lateral aspect of medial femoral condyle (also in elbow and
ankle)
 Unilateral (74% of cases)
 Twice as common in Males
 Classically occurs below age of 18
 Rare conditions of unclear etiology – most likely from wear and tear,
overloading on joint surface
 Loose bodies may cause joint locking, pts may walk with leg externally
rotated to avoid impingement of lesion on the femoral condyle
 Prognoses:
 Better if: immature growth plate or bony fragment not detached –
Usually heals with non-operative tx
 Worse if: growth plate closed or detached bony fragment (leaves defect
in weight bearing region) – Arthroscopic tx with possible ORIF

7. Loose bony fragment, medial femoral epicondyle
Demonstrating defect of
articular carilage and
subchondral bone

8.  Gaillard F, Weerakkidy Y, et al. Osteochondritis dissecans,
Radiology Reference Article:
http://radiopaedia.org/articles/osteochondritis_dissecans
 Simon RR, Sherman SC: Emergency Orthopedics, 6th ed.
Chapter 9: Cervical Spine Trauma.
www.accessemergencymedicine.com
 Tintinalli’s Emergency Medicine: A Comprehensive Study
Guide, 7th ed. Chapter 255: Spine and Spinal Cord Trauma
 http://www.wheelessonline.com/ortho/osteochondritis_di
ssecans_of_the_knee