Core decompression with bone marrow injection : Preliminary results of a prospective randomized study assessing the effect of Rh-BMP7 MIGAUD H, BOCQUET D, PINOIT Y, MAY O, COTTEN A, HERENT S, LAFFARGUE P

Services d’Orthopédie C et de Radiologie Ostéo Articulaire, CHRU de Lille

Introduction (1)

• • Disappointing results after core decompression Frequent failures – Evolutive femoral head deformity – Sub-trochanteric fractures • • Long delay before weight bearing Unpredictable results even at early stages of AVN

Introduction (2)

• • Core decompression improvement – Percutaneous surgery – Autologus bone marrow injection (but variable activity according to AVN etiology) – Rh-BMP7 injection Purpose – To asses this new method – To asses efficacy and tolerance of BMP7 injection with bone marrow

Patients and Methods (1)

• • • • • Prospective randomized Two arms 1) 2) Decomp. + bone marrow Decomp. + bone marrow + Rh-BMP7 Randomization according to Rh-BMP7 (OP1) availability Stages I to IIIA Ficat enrolled (Head deformity < 3mm) Main criteria of results = rate of conversion to THR +/- BMP7

• • • •

10

Patients and Methods (2)

8

One surgeon 24 hips included

2 1 0 7 6 5 4 3

Mean Follow-up = 12 months (6 to 30)

1 Stage 1 1 BMP 7 Stage 2 4 BMP+ 4 Stage 3 7

12 hips in group BMP and 12 in group BMP+

15 13 11 9 13

Etiology of AVN

8 7 5 3 1 -1 1 Alcoholic Steroids Metabolic 2 Genetics

Results (1)

• • • • • No infection All treated as outpatient except for 2 patients who had controlateral THR at the same time Immediate full weight bearing No sub-trochanteric fracture 4 heterotopic ossifications in vastus lateralis (all in BMP+ arm)  Spontaneous favorable healing

Results (2)

• • • • Seven failures (THR conversion) 4 in BMP+ and 3 in BMP- arms 3 already converted – All in BMP+ arm – All were stages III before core decompression, one bilateral and one controlateral to THR 4 were impending failures – – – 1 Stage III (BMP+ arm) 2 Stages II (2 in BMP- arms) 1 Stage I (in BMP- arm) revised by a new core decompression + bone marrow + Rh-BMP7 3b 3a 3b 3a -> 3b 3a

Success Failure

Results (3)

• • No significant difference according to : – AVN Ficat stages – Rh-BMP7 use – Etiology of AVN (steroids) 12 Months

15 13 11 9 7 5 3 1 -1 20 18 16 14 12 10 8 6 4 2 0 3 9 Stages 1 + 2 3 9 BMP Success

J0

4 7 Stage 3 Failure 4 8

Conclusions (1)

• Simple technique, allowing outpatient procedure and early recovery of full weight bearing • No adverse effect of using BMP7, but no advantage in terms of preventing THR conversion • But there was no assessment of bone marrow activity (confounding factor) • Incorrect randomization related to OP1 availability (cost)

Conclusions (2)

• • • BMP+ group had a higher rate of Stage III (but NS). BMP prevented from a higher rate of failure ? MRI bone healing only in BMP+ arm The procedure does not worsen a subsequent THR – no skin, muscular, bone scars – no ossification after THR conversion in BMP+ arm J0

10 9 8 7 6 2 1 0 5 4 3 1 1 Stage 1 BMP 7 BMP+ 4 Stage 2 4 7 Stage 3

24 M 24 M

The future (3)

• • • • Starting a double blind randomized study comparing Core decompression versus Core decompression + bone marrow + BMP7 Assessment of bone marrow activity (CFU F, ….) Results according to AVN volume on MRI 80 hips followed 5 years (40 BMP+ / 40 BMP-)

Thank you for your Attention

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10 9 8 7 6 5 4 3 2 1 0 3 5 Std 1/2 BMP Succès 0 5 Std 1/2 BMP+ Echec 1 3 3 4 Std 3 BMP- Std 3 BMP+

22 17 12 7 2 -3 Succès

NS

0 4 Ossifications Echec 7 13 Non

15 13 11 9 7 5 3 1 -1 0 Non Ossifications

P = 0,02

4 12 8 BMP BMP+

Success Failure

Results (3)

• • No significant difference according to : – AVN Ficat stages – Rh-BMP7 use – Etiology of AVN (steroids) 12 Months

15 13 11 9 7 5 3 1 -1 20 18 16 14 12 10 8 6 4 2 0 3 9 Stages 1 + 2 3 9 BMP Success

J0

4 7 Stage 3 Failure 4 8