Pathogenesis, epidemiology and treatment of Subachondral cysts.

1. M. A. Imam, Richard Field
Presented by
Professor M. A. Imam
MD, MSc (Orth)(Hons), D.SportMed, Ph.D., FRCS (Tr. and Orth.)
Consultant Trauma and Upper Limb Surgeon, Rowley Bristow Orthopaedic Unit, Chertsey
Professor and MD, Smart Health Academic Unit, University of East London, London, UK
Email: Info@theArmDoc.co.uk
www.TheArmDoc.co.uk
@MoAImam
Subchondral Cysts

2. Why do cysts occur?
• Congenital

3. Why do cysts occur?
• Secondary to subchondral bone damage

7. Why do cysts occur?
• By fluid erosion/necrosis

8. Pathogenesis of the subcondral cyst
Synovial fluid entrance thorugh
fissures and trabeculae fractures
P
Pressurized Fluid
causes cysts growth

9. Cysts can be painful

10. Treatment options

11. Solution 1 – Improve the joint

12. Solution 2 – Masterful inactivity

13. Solution 2 – Masterful inactivity

14. Solution 2 – Masterful inactivity
Followed by THR and cyst healing

15. Solution 3 – Remove them

16. Equine model
Medial femoral condyle
Lameness – 25% return to athletic activity without surgery
Extra-articular approach, poor results attributed to inadequate clearance of
cyst and removal of sclerotic cyst wall
Intra-articular curettage and grafting achieves 75% return to athletic activity
Solution 4 – Remove & Graft

17. Mosaicplasty of femoral head
(A) Recipient plug prepared
(B) Plug inserted into prepared hole with the press fit technique.
(C) Completed insertion of plug
Oper Tech Sports Med 16:194-200

18. FT chondral defect of the femoral head initially treated with open autologous osteochondral mosaicplasty
Oper Tech Sports Med 16:201-206
Mosaicplasty & ACI
of femoral head
Patient then underwent autologous chondrocyte implantation after disease progression

19. Larger Femoral Cysts
Jamali et al.,
Arthroscopy, 2010
Grafting

20. ORTHOPEDICS | ORTHOSuperSite.com
2 Patient case series
Used fresh-stored, non irradiated osteochondral allografts obtained from the
Musculoskeletal Transplant Foundation:
•Patient 1: the donor graft consisted of an allograft acetabulum
•Patient 2: a medial tibial plateau donor graft

22. Male 63 Female 54
Female 31 Female 45

24. Understanding the
Pathogenesis

37. Algorithm for management of
associated subchondral cysts
1. Remove cause of damage

41. Algorithm for management of
associated subchondral cysts
1. Remove source of damage
2. Clear the cyst and remove the sclerotic wall

43. Algorithm for management of
associated subchondral cysts
1. Remove source of damage
2. Clear the cyst and remove the sclerotic wall
3. Graft the cyst

44. Arthroscopy 2010;26(2): 279-285
Bone Grafting of
acetabular defect

46. Algorithm for management of
associated subchondral cysts
1. Remove source of damage
2. Clear the cyst and remove the sclerotic wall
3. Graft the cyst
4. Restore the labrochondral integrity

49. Should we take note of
Subchondral cysts?
Do they influence our
interventions?

50. Incidence of cases
No
acetabular
cysts
With
acetabular
cysts

51. Average age of Patients
38.2
46.7
25.0
30.0
35.0
40.0
45.0
50.0
No acetabular cysts With acetabular
cysts

52. Types of acetabular subchondral cysts
Solitary rim cyst
Solitary dome cyst
Multiple cysts

53. Associated radiological changes
0
10
20
30
40
50
60
70
80
90
100
No Cysts Solitary Rim
Cyst
Solitary
Dome Cysts
Multiple
Cysts
Joint space
narrowing
Subchodral
sclerosiS
Acetabular
osteophytes
Femoral
osteophytes

54. Interventions undertaken
0
10
20
30
40
50
60
70
No cysts Solitary Rim Cyst Solitary Dome
Cyst
Multiple Cysts
Rim Recession
Labral Repair
Miocrofracturing
+/- chondral graft
Femoral
osteochondroplasty

55. 0
5
10
15
20
25
No Cysts Single Rim Cyst Single Dome Cyst Multiple Cysts
Average NAHS increase at three
months post surgery

56. 0
10
20
30
40
50
60
No Cysts Single Rim Cyst Single Dome
Cyst
Multiple Cysts
% of possible improvement
achieved at three months

57. In conclusion
• Cases without cysts do well
• A solitary rim cyst does not adversely affect
outcome
• A solitary dome cyst suggests a different
pathological process and has a poor prognosis
• Multiple cysts indicate progressive
degenerative joint disease and have a poor
prognosis

58. Thank you