1. Charnley-Kerboull THA for AVN: A minimal 10-year follow-up study C. Nich, J.P. Courpied, M. Kerboull M. Postel, M. Hamadouche Service A de Chirurgie Orthopédique et Reconstructrice Université R. Descartes, Hôpital Cochin

2. Introduction  THA for AVN - Higher risk of complication (dislocation) - High mechanical failure rate  AVN risk factor itself for failure Chandler et al., J Bone Joint Surg Am, 1981 Collis et al., J Bone Joint Surg Am, 1984 Cornel et al., Orthop Clin North Am, 1985 Dorr el al., J Bone Joint Surg Am, 1983 Ortiguera et al., J Arthroplasty, 1999 Ranawat et al., J Bone Joint Surg Am, 1984

3. Clinical and Radiographic outcome of Charnley-Kerboull THA in AVN Minimum 10-year follow-up Predictive factors Aim:

4. Materials and Methods  122 consecutive THAs for AVN (1980 – 1990)  96 patients: 70 men, 26 females  Mean age: 50.8 ± 13.3 years (21 to 85)  3 senior surgeons  Underlying disease: idiopathic 40.6 %Ethanol 16.7 % Steroids 19.8 % Post-traumatic 11.5 % Others 12.2 %

5.  Ficat and Arlet grading: 66 % grade III, 34 % grade IV  Extent of necrosis (Kerboull et al., JBJS-Br, 1974) : 187° ± 70°  13 hips previous surgery: - 10 fracture fixation - 2 core decompression - 1 Vernon Luck cup Materials and Methods

6.  Trans-trochnateric approach  Single THA design: Charnley-Kerboull monobloc 316L SS, polished (Ra = 0.04  m) 22.2 mm head all-polyethylene cup cemented with CMW 1

7. Evaluation  Clinical results: Merle d’Aubigné hip score  AP view of the pelvis: - loosening (Harris et al. JBJS-A, 1982 ) - osteolysis (Maloney et al. JBJS-A, 1990 ) - wear (Livermore et al. JBJS-A, 1990 )  Survival analysis: - actuarial method - log rank

8. RESULTS  13 patients (16 hips) LTFU 3.4 years (0.8 to 6.5)  19 patients (24 hips) deceased 4.3 years (0 to 11,8)  5 patients (7 hips) revised 10.5 years (1.7 to 12)  59 patients (75 hips) not revised - mean FU 12.8 ± 2.6 years (10 to 20.8)

9. Complications  Medical (myocardial, cerebral infarction) 2  Dislocation: 4 including 3 single episode 1 recurrent  Greater trochanter nonunion: 1  Brooker class III: 1 (HO removal)  Deep infection: 1

10. Revisions  7 hips (5 patients): 9.6 ± 3.6 years  1 hip: septic loosening  6 hips: aseptic loosening high polyethylene wear and osteolysis no loosened femoral component acetabular reconstruction (Kerboull device)

11. Bilat OH AVN (53 years) Bilat THA 1983 Wear and osteolysis 1993Bilateral revision

12. Results  Clinical results: - 10.8 ± 2.5 pre-op to 17.4 ± 0.6 last FU p < 0.001 (Wilcoxon) - age, underlying disease: NS - 94.6% rated excellent to good  Radiographic results  Mean wear: 0.06 ± 0.08 mm/year unrevised hips 0.33 ± 0.06 mm/year revised hips Acetabular Side63102 No RL Incplete RL Cplete RL Femoral Side6951 p = 0.008 Mann-Whitney

13. Survivorship analysis @ 15 years  Revision for any reason: 88.5 ± 4.3 % (95% CI, 80.2 to 96.9%)  Revision for aseptic loosening: 89.8 ± 4.1 % (95% CI, 81.7 to 97.9%)

14. 0 20 40 60 80 100 051015 Follow-up (years) Survival rate (%) Acetabular components Femoral components 85.6% 98.6% Survivorship analysis @ 15 years End-point = Radiographic loosening

15. Age at index THA Gender Ficat and Arlet Stage Underlying disease Kerboull Necrotic Angle NS Predictive factors of radiographic loosening (Log rank)

16. Survivorship analysis @ 15 years End-point = Radiographic loosening 0 20 40 60 80 100 051015 Follow-up (years) Survival rate (%) Wear rate ≤ 0.1 mm/year (n=100) Wear rate > 0.1 mm/year (n=22) 94.4% 56.2% p = 0.04 Log rank

17. Discussion  Controversial published results  Cemented implants: Poor results / osteoarthritis Chandler et al., J Bone Joint Surg Am, 1981 Collis et al., J Bone Joint Surg Am, 1984 Cornel et al., Orthop Clin North Am, 1985 Dorr el al., J Bone Joint Surg Am, 1983 Ortiguera et al., J Arthroplasty, 1999 Ranawat et al., J Bone Joint Surg Am, 1984 Cementing technique Ritter et al, Clin Orthop, 1997

18. Discussion  Cementless implants (early generation): - high incidence of thigh pain - failure up to 20.5% @ 9-year FU  Hartley et al., JBJS A, 2000 - 10 different stems, 3 cup designs - 79.7 ± 13% @ 10-year FU Katz et al., Clin Orthop 1992 Lins et al., Clin Orthop 1993 Kim et al., Clin Orthop 1995Stulberg et al., Clin Orthop 1997 Wear and osteolysis

19. Discussion  Cementless Vs Cemented stems (prospective studies) - Katz et al., Clin Orthop 1992 - Kim et al., J Bone Joint Surg A, 2003 NS  Berry et al., J Bone Joint Surg A, 2002 - Mayo Hip Register, Charnley THA - 103 AVN (25-year FU) - Multivariate analysis: AVN ( odds ratio 0.9, p =.645)

20. Conclusion  Current study - single implant, single technique - min 10-year FU  Low friction = GOLD STANDARD - wear < 0.1 mm/year - highly cross-linked PE ? 21-year FU