OSTEONECROSIS OF THE FEMORAL HEAD:

Modern Results of Total Hip Arthroplasty

Daniel J. Berry, MD

Prof and Chairman

Mayo Clinic

Rochester, MN

OSTEONECROSIS: THAIntroduction

Advantages of THA:• THA is the one form

of treatment for osteonecrosis with an extremely high likelihood of excellent pain relief and good function

OSTEONECROSIS: THAResults

• What are the results of THA in the osteonecrosis patient population?

OSTEONECROSIS: THAResults

Pain Relief and Function:• Good• Similar pain relief

and function to THA for other diagnoses

OSTEONECROSIS: THAResults

Pain Relief and Function:• THA provides more complete/

reliable pain relief than hemiarthroplasty or head sparing procedures

Ito et al, CORR 2000

Cabanela, CORR 1990

OSTEONECROSIS: THAResults

THA Durability in osteonecrosis:

• The most controversial topic when discussing THA for osteonecrosis

OSTEONECROSIS: THAResults

• Difficult to disentangle the fact that most osteonecrosis cohorts have high frequency of demographic factors and underlying diagnoses that put them at risk for implant loosening and wear

OSTEONECROSIS: THAResults

• Osteonecrosis patients frequently young and active

• Osteonecrosis includes very high activity subgroups; e.g. post-traumatic

OSTEONECROSIS: THAResults

Durability: Literature• One body of literature: THA for osteonecrosis less

durable (loosening/lysis) than THA for osteoarthritis• Another body of literature: little difference in durability

between THA for osteonecrosis and other diagnoses

Ortiguera et al, J Arthrop, 1999 Sarmiento et al, JBJS(A), 1990Chiu et al, J Arthrop, 1997 Mont, Hungerford, JBJS(A) 1995Xenakis et al, CORR, 1997

THA FOR OSTEONECROSISUncemented THA

• These are historical results• What are the results with

more modern techniques?

THA FOR OSTEONECROSISNew Mayo Series

• 98 uncemented THA• 1991-2000• 60 male, 38 female• Mean age 37 years• Mean F/U 6 yrs

Guyen, Cabanela, Berry, 2005

THA FOR OSTEONECROSISNew Mayo Series

• All treated with uncemented HA coated tapered stem

• 28 mm head on conventional PE

THA FOR OSTEONECROSISNew Mayo Series

Re-operations for aseptic femoral or acetabular loosening:

• 0/98 = 0%

THA FOR OSTEONECROSISNew Mayo Series

Re-operations for bearing wear/osteolysis:

• 8/98 = 8%*

* all had conventional PE bearing

OSTEONECROSIS: THAResults

Literature comparison: • Good results with other successful

uncemented designs*- extensively porous coated femoral

implants**- successful tapered uncemented stems***

* Xenakis et al, CORR 1997

** Piston et al, JBJS(A) 1994

***D’Antonio et al, CORR 1997

THA FOR OSTEONECROSISLessons Learned

• Modern uncemented THA is outperforming historical results of cemented THA osteonecrosis patients

• The fixation results are comparable to uncemented THA for other diagnoses

THA FOR OSTEONECROSISLessons Learned

• Wear and osteolysis rates in this young patient group are unacceptable with conventional PE bearing surface

• Alternative bearings (ceramic, metal, crosslinked PE) are justified

THA FOR OSTEONECROSISDislocation Risk

• Are osteonecrosis patients at higher risk for dislocation?

LONG TERM DISLOCATION RISKMaterials and Methods

• All primary Charnley THA performed at Mayo Clinic 1969-1984

• 6623 hips

JBJS (A), Jan 2004

OSTEONECROSIS: THAComplications

• Dislocation risk is elevated in AVN population

0

10

20

0 5 10 15 20 25 30

Years after surgeryYears after surgery

AVNAVN

DJDDJDCumulative

probability ofdislocation

(%)

Cumulativeprobability ofdislocation

(%)

LONG TERM DISLOCATION RISKResults

Risk of Dislocation (Compared to Osteoarthritis)

Factor Relative Risk (CI)

Dx=Osteonecrosis 1.9 (1.1-3.2)

p<0.01

OSTEONECROSIS: THAComplications

Literature: Dislocation rate also high in other series:

• compliance problems in subgroups of patients (EtOH)

• less capsular hypertrophy in osteonecrosis than osteoarthritis

THA FOR OSTEONECROSISLessons Learned

Instability risk elevated in osteonecrosis:

• Efforts to minimize instability justified - anterior approaches or- posterior approach with

capsular repair- larger head size (≥ 32 mm)