We may have embraced the entirely new treatment concept which is possibly based on some assumptions. Subchondroplasty is probably indicated mainly for the treatment of subchondral cysts and cavities, rather than various bone marrow oedema conditions, most of which do not seem to need surgical treatment, as they get better given time. The aetiology of various conditions, known generically as “bone marrow oedema” (or perhaps more correctly “bone marrow lesions”), is very different and it is still poorly understood and therefore it is difficult to decide when the surgical treatment is necessary and what is the most appropriate treatment. Bone marrow oedema, as a metabolic (possibly vascular remodelling rather than degenerative) process does not seem to lack bone, and therefore injecting bone substitute is probably not the best ingredient. To the contrary, injecting bone paste may clog subchondral microtrabecular bone spaces and may slow down or prevent subchondral repair and remodelling by blocking neurovascular pathways. It is difficult to accept that patients "should expect 3 days of severe pain" postoperatively, but even if we do this is probably not acceptable, because injected and cured bone substitute may increase intra-osseous pressure (which is already higher than normal, especially in SONK-like conditions, which are very painful to start with) and block metabolic (vascular) pathways. Unsurprisingly, in some cases, biopsy of the subchondroplasty area treated with on calcium phosphate paste has shown necrotic or nonviable bone a few years postoperatively. However, long-lasting symptomatic bone marrow oedema and SONK-like lesions, may benefit biologically and structurally from the surgical treatment with more biologically desirable ingredient, such as autologous bone marrow aspirate, delivered directly to the intra-osseous area affected with bone marrow oedema. This is where subchondroplasty, using autologous bone marrow aspirate, autologous stem cells or even autologous PRP gets entirely new biological meaning and possibly becomes more useful therapeutically.

1. Surgical Treatment of
Symptomatic Subchondral Activity
(or Bone Marrow Oedema or Bone Marrow Lesion)
What are we treating? Why? How?
Mr Vladimir Bobić, MD FRCS Ed, Consultant Orthopaedic Knee Surgeon, Chester Knee Clinic
www.kneeclinic.info office@kneeclinic.info @ChesterKnee
ICRS Focus Meeting
Roma, Italia, 5 to 7 June 2019
www.slideshare.net/vbobic

2. Great to be back: I trained in limb lengthening with Prof Monticelli and Prof
Spinelli and knee arthroscopy with Prof Pier Paolo Mariani in Rome in 1985

3. My clinic is based in
the Roman city of
Chester, a.k.a Deva.
Deva Victrix was a
legionary fortress,
port and town in
Roman province of
Britannia.
Deva was developed
as a possible capital
but Londinium took
over!
We have the the
largest military
amphitheatre in
Britain.
Here is a list of the
things that Romans
introduced to
Britain:
Contemporary Roman Legionnaires
(Chester University Porters) June 2019

4. ICRS MR Cartilage
Imaging Protocol
January 2000
CKC UK

5. MARIARC MRI, UK (1997)
The orange pixels correspond to normal T2 values for bone. The blue and
purple pixels are anomalous: the T2 relaxation times are elevated because the
tissue is "wetter" than normal (the fluid interface between recipient and
donor bone).
OAT MRI analysis
MR Imaging Protocol 1997: Dr David Ritchie, Consultant Musculoskeletal Radiologist, Liverpool (now Glasgow), UK

6. Osteochondral Functional Unit
Source: Dr Carl Winalski, Boston, USA, 2003
CKC UK

7. Sports Knee Surgery Symposium
The University of Warwick
3 and 4 November 2003
Bone Bruise and Bone Marrow
Oedema: Bad News
for Articulating Surfaces
Vladimir Bobić, MD FRCS Ed
Consultant Orthopaedic Knee Surgeon
CKC UK

8. So, here we go …

9. Surgical Treatment of
Symptomatic Subchondral Activity
(or Bone Marrow Oedema or Bone Marrow Lesion)
What are we treating? Why? How?
Mr Vladimir Bobić, MD FRCS Ed, Consultant Orthopaedic Knee Surgeon, Chester Knee Clinic
www.kneeclinic.info office@kneeclinic.info @ChesterKnee
ICRS Focus Meeting
Roma, Italia, 5 to 7 June 2019
www.slideshare.net/vbobic

10. The entire presentation is available on: www.slideshare.net/vbobic

12. Subchondroplasty
Procedure with CP

13. Subchondroplasty: 1st Take Home Message:
CKC UK

14. CKC UK

15. The 1st report on complications after
a calcium phosphate subchondroplasty
CKC UK

16. CKC UK

17. The Structure of Subchondral Bone
Redrawn from: Imhof H, Breitenseher M, Kainberger F, Rand T, Trattnig S. (1999): Importance of subchondral bone to
articular cartilage in health and disease. Top Magn Reson Imaging 10:180–192
A surprisingly high number of arterial and venous vessels, as well
as nerves, can be seen in the subchondral region sending tiny
branches into the calcified cartilage …

18. Why? Well, BME is not necessarily a problem!
CKC UK

19. ACL injury + extensive BB
CKC MRI 110206
Gone after 7 months
Traumatic bone bruise = many local microtrabecular fractures
CKC UK

20. Shifting Bone Marrow Oedema = Remodelling Overdrive?
Shifting Bone Marrow Oedema is a self-contained disorder involving both femoral
condyles. On MRI it exhibits vast marrow oedema and is most likely an event on the SONK
timeline. Gets better (asymptomatic), eventually!
CKC UK

21. Persisting BME after Microfracture
Source: Carl Winalski, BWH, Boston
CKC UK

22. MFC ACI, 6/12: “In the medial
compartment, the ACI graft has
been placed over the central
weight-bearing portion of the
medial femoral condyle. Small
cartilage flap at the interface
peripherally in keeping with
minor delamination but
otherwise the graft appears good
with no cartilage overgrowth or
major defects. The
inhomogeneity of the implant
cartilage and mild marrow
oedema-like signal beneath
the graft are expected normal
findings 6 months after the
procedure.”
Unedited MRI report.
Dr David Ritchie, Glasgow, UK
CKC MRI 260906
“Normal” Bone Marrow Oedema 6/12 after MFC ACI
CKC UK

23. Long term ACI FU & MRI and BME
CKC UK
VB: I know, but for how long?

24. Post-arthroscopy Spontaneous Osteonecrosis (SONK)
• Ahlback et al first described
spontaneous osteonecrosis of the
knee as a distinct clinical entity in
1968.
• Osteonecrosis of the knee has also
been described as a postsurgical
complication following
arthroscopic meniscectomy
(Muscolo et al., Prues-Latour et al.)
and following radiofrequency-
assisted arthroscopic treatments,
mainly in 50+ age groups.
• The pathophysiology of osteonecrosis
following these arthroscopic
procedures is not fully understood
(vascular isufficiency, trabecular
microfractures?), or, more likely, a
consequence of pre-arthrosopy
osteopoenia and altered focal
biomechanics (bone density
should be looked into).
CKC UK

25. Post-arthroscopy BME (SONK?)
CKC UK 2018

26. CKC UK
Spontaneous BME + Insufficiency Fracture

27. Insufficiency Fracture and BME - Things get better, given time!
CKC UK

28. SONK (Spontaneous Osteonecrosis)
with Residual Insufficiency Fracture
CKC UK

29. Symptomatic Treatable Subchondral Cyst (with CP and BMC)
CKC UK

30. CKC UK
Subchondral Cysts Are Not Good But Do not Need Treatment

31. CKC UK
Symptomatic Treatable MTC BME (with intraosseous BMA)

32. CKC UK
Spontaneous SONK + Insufficiency Fracture:
relatively asymptomatic, getting better slowly …

33. SONK Before and After Subchondral Decompression
• 15/12/08: subarticular
insufficiency fracture and slight
flattening of the MFC and prominent
subarticular marrow oedema more
marked on the femoral side. Since
04/04/08, significant deterioration
in the medial compartment with
SONK-like process, progressive
degenerative changes …
• 11/09/09: Comparison is made with
the previous scan 15/12/2008. In
the medial compartment, following
the subchondral decompression,
there is now evidence of
articular irregularity, deficiency
and thinning of articular
cartilage, slight increase in the
subarticular marrow oedema
and early subarticular cyst
formation in the outer aspect of
the MFC …
CKC UK

34. The Importance of Autologous Bone Marrow
CKC UK
Dr Philippe Hernigou, Paris

35. Autologous Bone Marrow Aspirate or Concentrate
CKC UK

36. Symptomatic Medial OA + BME: PT Declined UKR or HTO
CKC UK

37. Asymptomatic Medial OA + BME 1 Year After OATS + SCD + ABMI
CKC UK

38. The CP Subchondroplasty Procedure:
Arguably, subchondroplasty with bone substitute is indicated mainly for the
treatment of subchondral cysts and cavities, rather than various bone marrow
oedema conditions.
Bone marrow oedema, as metabolic (vascular) “event” does not lack bone
(therefore injecting bone substitute is not the right ingredient). To the contrary,
injecting bone paste will clog many interconnected cellular spaces and will slow
down or prevent subchondral repair and remodelling.
Injected and cured bone paste will increase intra-osseous pressure (which is
already higher than normal and which is why SONK-like conditions are very painful
to start with) and block metabolic (vascular) pathways!
However, the real (biologically) desirable ingredient is autologous bone marrow
aspirate (or autologous stem cells or even PRP), delivered to the area affected
with bone marrow oedema.
Vladimir Bobic CKC: Articular Cartilage, Subchondral Bone and Osteochondral Unit. 4th BKS Meeting, Cardiff, UK 1-2 February 2018.

39. CKC UK

40. Targeted Intraosseous Delivery of Autologous Bone Marrow
CKC UK

41. Intraosseous Injection of Autologous Bone Marrow
CKC UK

42. Other Take Home Messages …
Do you really have to treat painful bone marrow
oedema? Think twice!
Do not treat MR images - treat the patient, holistically!
Take time: wait, review, repeat the scan …
If you decide to treat “symptomatic bone marrow
oedema”, discuss everything with the patient and
document everything.
Do not use bone substitutes, use autologous bone
marrow.
Do not restrict WB and ROM!
And finally, remember:
CKC UK

43. … and the last Take Home Message:
CKC UK

44. Thank You for Your Attention
Everything We Know About
Articular Cartilage
A Lot More We do Not Know About
Subchondral Bone and
Osteochondral Unit
(Known and Unknown Unknowns)
www.slideshare.net/vbobic
CKC UK