Partial Surface Replacement5 to 14 Years Results

T. JUDET T.SIGUIER J-L.MARMORAT P.PIRIOU B.BRUMPT M.SIGUIER

Raymond PoincaréJouvenet IMK 2006

Osteonecrosis mainly affects young patients: How to avoid THR?

• Core decompression• Cancellous bone

grafting• Vascularized bone

grafting• Intertrochanteric

osteotomies• Rotationnal basi-

cervical ostéotomies

Drawbacks, limits and failures of conservative surgery

• Technically over-demanding procedure

• Long lasting rehabilitation

• Unpredictable results

• Controversial efficiency

• Major anatomical disturbance of the upper femur

Partial resurfacing conceptMarc Siguier 1990

• Minimalist design and operative technic

• Replacement anatomically limited to the pathologic area

• Preservation of the hip anatomy

• Preservation of the mecanical properties of the femoral neck

The MMS Implant

• 120° Covering area• Range 40 to 60 mm

diameter to match the exact sphericity (2mm increment)

• Dedicated instrumentation for each size

• Cemented fixation

Surgical technic

• Anterior approach on fracture table

• T-shaped capsulotomy

• Anterior dislocation preserving circumflex vessels

• Excision of the ostéochondral collapse and under-lying loose necrotic bone

Surgical technic

• Measurement of the femoral head

• Preparation of the prosthesis setting in line with the center of the head

Surgical technic

• Trial implantation without tilting and flush or beneath the surface of the healthy remaining cartilage

• Cementation of the definitive prosthesis

Post operative care

Immediate rehabilitation and full weight-bearing

Interrogations and potential problems

• Quality of bone-implant fixation

• Evolutivity of the pre-OP necrotic area

• Post-OP extension of the necrotic area toward the pre OP limits

• Cartilage tolerance to the implant and further degenerative changes

Previous published results

• Siguier M , Judet T, Siguier T & al J.Arthroplasty 1999 Preliminary results of partial surface replacement of the femoral head

in osteonecrosis 25 procedures 6 failures (FU 20-60 mths)

• Siguier T, Siguier M, Judet T & al Clin. Orthop. 2001 Partial resurfacing arthroplasty of the femoral head in avascular

necrosis Methode, indication and results 37 procedures 9 failures (FU 24-89 mths)

Actual Serie

• Continuous Serie April 1991 - Jan 2001• 61 MMS procedures (54 patients)• Age 42 years (24 - 59)• 45 Males et 9 females• Aetiologies Post trauma 6 cases Steroïds 11 Cases (9 patients) Alcool/tobacco 7 cases (5 patients) Idiopathic 35 cases (32 patients)

Clinical Pre- operative Status

• Postel Merle-d’Aubigné score

12 pts (8 - 17)

Pain 2,3 pts (1 - 4)

No preventive surgery

Radiological Pre-operative status

• Ficat & Arlet Staging– Stade II : 1 case– Stade III : 41 cases (67 %)– Stade IV : 19 cases (31 %)

Radiological Pre-operative status

• Evaluation of the necrotic area size after M.Kerboul

-Angular measurement on AP view and Lequesne false profile view

Mean angle AP : 121° (70 to 180)

Mean angle Profile : 116° (50 to 180)

Radiological Pre-operative status

• Evaluation of the necrotic area size

-Max depth of the necrotic area; 4 zones to define superficial or deep involvement

Stage 2 : 28 %Stage 3 : 53 %Stage 4 : 19 %

Results : 56 over 61 implants

1 deceased (2 hips) and 2 patients (3 hips) lost to FU before 5 Yrs

• Implant removal : 31 cases

• Implant still in place : 25 cases

Results : Implant removal : 31 cases

- early technical failure

- extension of the necrotic zone - head collapse

Results : Implant removal : 31 cases

- sinking of the implant

- joint line narrowing and degenerative changes

No difference statistically significant : failure vs Ficat staging

Difference statistically significant : failure vs depth (p < 0,01)

Relatively correct bone/implant stability

Survival curve

• End point : implant removal

Cumulative Survival

0

10

20

30

40

50

60

70

80

90

100

1 2 3 4 5 6 7 8 9 10 11 12 13 14

Years

% S

urv

ivin

g

Second look surgery

• THR through the same mini invasive anterior approach

• Resurfacing arthroplasty

• No difficulty related to the previous surgery

Conclusion

• Optimistic : for 25 patients 40 yrs old, improvement lasting 8 years (5 - 14,5) with a pain scoring rising from 2,3 to 5,1.

No deleterious effect on secondary procedure

• Realistic : survey curve 50 % à 10 years

46,5 % à 14 years

Conclusion

• Prospective in the up to date context of

mini-invasive surgery, mini-implants are highly attractive and our long term experience of partial hemi resurfacing of the femoral head must render any surgeon very prudent concerning analogous procedures.

Conclusion

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THANK YOUMERCI