Distal femoral fresh osteochondral allografts

1. I N V E S T I G A T I O N P E R F O R M E D A T M O U N T S I N A I
H O S P I T A L , T O R O N T O , O N T A R I O , C A N A D A
P U B L I S H E D I N T H E J O U R N A L O F B O N E A N D J O I N T
S U R G E R Y , @ 2 0 1 4
Distal Femoral Fresh Osteochondral Allografts
Follow-up at a Mean of Twenty-two Years

2. Introduction
 The prevalence of symptomatic osteochondral
lesions of the knee in young, active patients is not
well documented, although reports have estimated a
20% prevalence of articular cartilage lesions in these
patients with traumatic hemarthrosis of the knee

3. Osteochondral dissecans
 Pathological destruction of
subcondral bone and articular
cartilage following necrosis

4. Occurrence

5. Etiology
 Trauma
 Vascular insufficency (micro trauma)
 Skeletal maturation.
 Metabolic factors.

6. Clinical features
 Vague and poorly localized pain.
 Clicking , poping , locking ( associated with activity)
 Effusion +
 Restricted ROM.

7. DIAGNOSIS
 X-RAY
 MRI
 Diagnostic arthroscopy
 Ultrasound
 Bone scan

8. Stages
ICRS classification
Grade 0 Normal
Grade 1 Superficial lesions (softening, fibrillations ,
lacerations anfd fissures )
Grade 2 Partial thickness defect ( cartilage depth <50%)
Grade 3 Partial thickness defect >50%
grade4 Full thickness defect with extension in to subcondral
bone
International cartilage research society

10. Stages
Radiolo
gical
grading
(french-
bedouell
e)
Stage 1 1 A- incomplete lesion
with well defined image
1 B- with more or few
calcifications
Stage 2 2 A – presence of
nodules
2 B – with more or less
shrinkage of nodules in
relations to condyles
Stage 3 Sleigh bell aspect
Stage 4 Free fragment in joint
with empty bed

11. Stages
Surgical staging of OCD
Stage 1 stable
lesion in continuity with the host bone
covered by intact cartilage
Stage 2 stable on probing
partial discontinuity of the lesion from the host
bone
Stage 3 unstable on probing
fragment not dislocated
complete discontinuity of the "dead in situ" lesion
Stage 4 dislocated fragment

12. Stages
Arthroscopic grading
(Guhl)
Stage 1 Irregularity and softening of cartilage. No definite
fragment seen.
Stage 2 Fissure in cartilage , definite fragment seen, buit
fragment not displaceable
Stage 3 Discrete fragment , displaceable,but still attached by
fibrous attachment or by overlying cartilage
Stage 4 Loose fragment and osteochondral defect

13. Stages
MRI grading
(Dipaola et al)
Stage 1 Thickening of cartilage ,No break in cartilage ,Low signal
changes
Stage 2 Fissure in cartilage, low signal rim behind fragment indicate
fibrous attachment.
Stage 3 Cartilage breached , high signal on T2
Stage 4 Loose body

14. Treatment
 Depends on age, stability and size of lesion .
 Stability is the prime determinant of surgical
treatment.
 Various technique for cartilage repairs or
reconstruction available to reduce pain and restore
function
- Goals : durable reconstruction perform for long
time and reproducing hyaline or hyaline like
regeneration.

15.  Indications for surgical reconstruction of cartilage
defect
- age < 50 (too early for arthroplasty).
- stable joint with accceptable alignment.
- nonobese (BMI <30)
- ICRS grade 3 or 4
- non kissing lesions
- lesion ( >0.5 sq.cm to <2-3 sq.cm )

16. Modalities of treatment
 Palliative :
- Neglect.
- Arthroscopic lavage.
- Radiofrequency ablation.
 Marrow stimulation (subcondral)
 Reconstruction using direct tissue transfer
- Mosaicplasty.
- Osteochondral autograft transfer
system.(OATS)
- Allograft implantation

17.  Newer tech to obtain hyaline cartilage
- cell based repair.
- scaffold based repair.
- cell +scaffold based repair.
- cell + scaffold + growth factor.

18.  Perforation: ( Pridie’s perforations)
- cartilage regeneration.
- multiple drill holes with k wire (power drill) in
subchondral bone.
- damges MSCs and produce necrotic bone.

19.  Abrasion condrolplasty ( Johnson’s)
- abraded using burr in exposed subcondral bone.
- exposes mesenchymal intra osseous vessels and
multipotent subcondral cells.
Abrasion chondroplasty

20.  Microfracture (Steadman’s) and CPM:
-minimally invasive.
- cartilage defect –debrided to stable and smooth
edges form pool for clot ( super clot)
- blood clots provides scaffold (GF and cyt).
- bone is scrapped to remove calcified cartilage layer.
- 6mm hole 3-4mm apart placed using awl.

22.  Mosaicplasty:
- harvesting small circular (4-8mm) autogeous graft
from non wt bearing portion of knee and
transpalnting it in mosaic pattern in osteo chondral
defect .
- < 45 yrs , >2cm defect.

24. AUTOLOGOUS CARTILAGE IMPLANTATION

25. Back ground
 To examine the long-term survival and clinical
outcomes of fresh osteochondral allograft for
posttraumatic and osteochondritis dissecans defects
in the knee.

26. Materials and methods
 Inclusion criteria:
- < 50 yrs of age.
- posttraumatic osteochondral or osteochondritis
dissecans defect that was limited to the distal aspect
of the femur (unipolar) and was larger than 3 cm in
diameter and 1 cm in depth.
 Exclusion criteria:
- Degenerative disease > 1 compartment or > 1
articular surface

27. Allograft Transplantation Procedure
 Standardized radiographs of the knees were obtained and
size matching of the donor to recipient was performed.
 Harvesting of the knee involved en bloc excision of the joint
with an intact capsule and synovial membrane.
 The donor knee then was placed in a sterile container with 1
g of cefazolin and 50,000 units of bacitracin per liter of
Lactated Ringer’s for storage at 4C until transplantation.

28.  A minimum of seventy-two hours was required for
viral and bacteriological screening.
 Transplantation was carried out from seventy-two
hours to seven days after harvesting.
 2 surgical teams involved one for graft preparation
and other recipient surgery.

29.  The recipient knee was approached through a midline incision.
 The knee was then exposed via a medial or lateral parapatellar
arthrotomy, depending on the condyle to be replaced.
 Excision of the articular defect was conducted, with care to
remove as little healthy tissue as possible, until a healthy
bleeding bone bed was reached.
 Measurements of the defect and the excised fragment were then
taken.

30.  On a separate table, the second surgical team removed all
soft tissue from the harvested knee.
 An osteochondral fragment matched in size to the excised
defect was inserted into the bone bed of the recipient knee
and fixed by two or three partially threaded, small fragment
cancellous screws of 3.5 mm in diameter

33.  An osteotomy to unload the graft was indicated if standing radiographs
showed that the weight-bearing axis would pass through the
compartment with the transplant
 If indicated, a realignment osteotomy for valgus or varus deformity was
performed at this stage with overcorrection of 2 to 3 degree.
 Wound closure was performed over a suction drain. A Jones-type
bandage was applied in the operating room

34.  Postoperatively, the knee was placed in a well-
molded, stove-pipe fiberglass cast after two or three
days.
 At two weeks, the cast was bivalved and
physiotherapy for knee motion and non-weight-
bearing ambulation was begun.
 Patients were fitted at this stage for a full-length
ischial weight-bearing orthotic, which was worn for
one year.

35. Outcome Measures
 Modified Hospital for Special Surgery (HSS) score
- McDermott et al
-assessment of preoperative status and
postoperative outcome at each clinic visit

36. Modified HSS Knee Score
Points
Pain intensity: How severe is your pain? None-35 ,Mild-28 ,Moderate-21,Severe-
14, Rest pain-0
Instability: Does your knee feel
unstable or give out?
No-10 ,Occasionally-7,Moderately-
4,Severe (use brace)-0
Walking aids: Do you use any walking
aids?
None-5,Cane-3,Crutches-1,Walker-0
Walking distance: On a flat surface (like
in a mall) how far can you walk?
>1 mile-10,1-5 blocks-6,1 block-3,Inside
house -1.Confined to bed-0
Extension block: Can you straighten
your knee as much as the normal side?
No deformity-10,<5-7, 5to10-4, 10to 20
-2, >20- 0
Flexion: How much can you bend your
knee?
>120-20, 90to120-15, 45to90-8, <45-0
Effusion: Is the knee swollen at this
time?
No-10, Moderately-5 ,Severely-0

37.  85 to 100 - excellent.
 75 to 84 - good.
 60 to 74 - fair.
 >60 - poor.

38. Results
Total patients 63
Period 1972 and 1995
Followed up 58
Lost follow up 5
Mean age group 28 years (11 to 40 years)
Mean follow up period 21.8 years (15 to 32years).
Etiology Trauma -76% OCD – 24%
Surgery lateral femoral
condyle graft-29
cases (50%)
medial femoral
condyle graft-29
(50%)

39.  13 of 58 cases required further surgery;
-3 -graft removal,
-9-total knee arthroplasty, and
-1 underwent multiple debridements followed
by above-the-knee amputation.
 3 patients died during the study due to unrelated
causes

40. Conclusion
 Fresh osteochondral allograft was found to provide a
long-term solution for large articular cartilage
defects in the distal aspect of the femur in young,
active patients.