Protesnära fraktur

Per Wretenberg

Problemet

Historik

Första beskrivningen 1954

Artificial hip prosthesis in acute and non-union

Fractures of femoral neck

Horwitz et al. JAMA 155; 564-567 1954

Historik

Traktionsbehandling, 3 månaders balanserat sträck

The healing of human fractures in contact with

acrylic cement

Charnley J. Clin Othop 47; 157-163, 1966

Incidence

1 - 2% after primary THR (increasing)

4 - 20% after revision THR

Kavanagh, JBJS (Br) 2002

Incidence

0.1 – 1% after Cemented THR

Kavanagh, Clin Orthop North Am, 2002

5.4% after uncemenetd THR

Berry, Clin Orthop, 2009

Incidence

Totala incidensen ökar

något.

Lindahl H, The periphrostetic femur fracture 2006 (Thesis)

Periprostetsik fraktur

Intraoperativt

jämfört med cementerad primärplastik

- större risk vid ocementerad protes

- större risk efter revisionevisioner

- större risk vid benpackning?

Postoperative

- trauma

- osteolysis

- tumör

Postop. rtg

Problem?

Reoperation

5 dagar senare

Riskfaktorer

Lös protes

Kvinnor

Metabola bensjukdomar

Osteoporos

RA

Preoperativ deformering av femur

Ocementerad protes

Vancouver classification

Type A: Trochanteric fractures

Type B: Fracture at stem level or just under the stem

Type C: Fracture distal to the stem

Type B fracture

B1: Stable prosthesis

B2: Loose prosthesis, good bone

B3: Loose prosthesis, bad bone

Vancouver classification

A = Type A

B = Type B1

C = Type B2

D = Type B3

E = Type C

Bone defects

Endolink classification

Vancouver classification reliability

Reliable classification,

Brady et al J Arthroplasty vol. 15(1) 2000

Vancouver classification reliability

Intra-observer k-value 0.77

Inter-observer k-value 0.64

K-value 0.10-0.20 = slight agreement

0.21-0.40 = fair

0.41-0.60 = moderate

0.61-0.80 = substantial

> 0.80 = almost perfect

Treatment of periprosthetic fractures

Nonoperativ

• Traction

• Orthosis

• None

» No adequate studies performed

Treatment

Vancover A

• Non operative, mobilization

• Fixation with screws

• Fixation with cables

• Fixation with plate and screws

Treatment

Vancover C

• Fixation with plate and screws

• Fixation with cables

• Fixation with nails

• (Fixation with screws alone)

Female

72-years

Vancover C

Treatment

Vancover B1

• Cables (prox undisplaced fracture)

• Plate and screw, and or cables

• Mennen plate

• Strut graft with or without plate

• Strut graft and bone packing

• Revision THA

Platefixation

• Good/exact reposition possible

• Early mobilisation

• Partial (or full) weight bearing

• Risk of devsacularisation

• Bone resorption under plate

• Cement influenced by screws?

• Plate fracture

• Non union !

+

-

Technique

• Good exposure of fracture site needed

• Reduction and preliminary fixation

• Plate adjustment

• Combination of screws, angular stable screws and cables

• With angular stable plates, less invasive technique is

possible.

74 year male, Vancover B1

Bra

funktion

efter

9 år

1 month postop 10 years postop

73-year male, Vancover B1

63-year female, Vancover B1, op 1994

New x-rays from Irak, 2010,

Good

function

79-year female, Vancover B1

4 months postop. 8 years postop

42-year male,

previous acetabular

fracture.

Vancover B1

Vinkelstabil platta

Vancover B1

94-årig kvinna, Vancover B1

Platefixation

Mont et al J Arthroplasty vol 9(5) 1994

Review of litterature 1964-1991

487 patients, 26 articles

Plate fixation not as good as revision arthroplasty

I USA har det varit mycket vanligt med

kombination platta-allograft, nu visar dom

bra resultat med bara platta

Vinkel-

stabila

plattor

fungerer

Mennen plate

Not ment for rigid fixation

Space between plate and bone to not disturbe cirkulation

Results?

Mennen plate

Cortical onlay strut allografts

Cortical onlay strut allografts

Good stability

Stimulate fracture healing

Can be incorporated in host bone and increase bone mass

Create less stress-shielding than plates

Expensive, hard to get

Reduced strength of graft after 4-6 months

Initial weigh bearing not recommended

+

-

Technique

Chandler et al JBJS 79A(9) 2012, from instructional course lecture AAOS

Femur allograft best

Divide allograft in two halves

Place allograft not less than 10 cm distal to the fracture site

4 cables on each side of the fracture

Place bone graft from host at the fracture site

Full weight bearing after 3 months

Cortical allografts, results

Haddad et al JBJS 84A(6) 2002

Multicenterstudy (4 centra)

40 patients op 1992-1996

Prosthesis well fixed, no need for revision

19 patients treated with only 1 strut allograft

21 patients treated with 1 or 2 allografts and plate

27 hips revised earlier

Reduced weight bearing 3 moths

Haddad et al,

Follow-up 6-78 months (mean 28 months)

39 of 40 fractures healed

radiograficaly

Treatment

Vancover B2, B3

•Revision THA

When the prosthesis is loose,

revision is necessary

The problem

How do we know

that the prosthesis is

loose?

Exposure!

Revision of prosthesis

Options

1. Cemented revision

2. Uncemented revision

Revision of prosthesis

Cemented revision

1. Option for older patients with less physical demand

2. Option for patients with pathological fracture

3. Good and stable reposition of the fracture must be possible

before cementing the prosthesis in place.

4. Long stem needed to bypass the fracture

Revision of prosthesis

Uncemented revision with distal fixation

1. Younger patients with higher physical demands

2. Complex fractures

55-year male, Vancover B2

Cemented

revision with

long stem

55-year female, Vancover B2

Postop 5 years postop

75-year male, Vancover B2

Wagner

Postop 10 yeras postop

84-year male, Vancover B3

4 – years post op.

Male 67-years, Vancover B2

MP-Link

1 year postop

MP-Link

59-year female, Vancover B2

Female, 55-years, Vancover B1??

3 months later…

MP-Link reconstruction

After 1 year

New bone formation

Male, 47 – years, Vancover B2

MP-Link reconstruction

MP-technique for fracture cases

• Exposure easy proximal, additional osteotomy could be done

• Distal cement must be extracted

• Prophylactic cables distally

• Positioning of stem and trial reduction could be done without

reduction of the proximal fragments

• Proximal fragments fixed with cables around stem

Resultat

Slutsatser

1. Majoriteten av patienter som fick en periprostetisk fraktur

hade redan en lös stam.

2. Implantat relaterade faktorer finns med överrisk för Charnley

och Exeter stammar av de cementerade.

3. Generellt dåliga resultat efter op. oavsett metod. Hög

reoperations frekvens och många komplikationer.

Kvinna född 1956,

HIV, op 4 år sedan

Revision med förtur

för att förhindra

fraktur

Slutsatser

1. B1 frakturer hade sämst resultat troligen beroende på att

stammen inte satt fast.

2. Exploration av stammen rekommenderas vid minsta tvekan

om stammen är lös. Är den ”misstänkt lös” => revidera!!

3. Mycket hög komplikationsrisk för plattfixation, troligen

beroende på att många patienter med lös protes

plattfixerades.

4. Fler infektioner vid plattosteosyntes än revision. Orsak? Fick

revisionerna mer antibiotika?

83-year male, Vancover B1??

Male 42-years, Vancover B1??

Completely stable prosthesis when

exposed => B1!, plate fixation possible

Female, 78 years. Vancover B1?

Completely unstable prosthesis when

exposed => B2!; revision

Tack!!