Cemented acetabulum

 

Cemented cup 1Cemented cup 2

 

Indications

 

Tumour / metastatic

Severe osteoporosis / elderly

Pagets

 

Design

 

ZCA cup

Zimmer ZCA all poly cup

 

Components

- all polyethylene

- spacers to ensure even cement mantle

- +/- flange to compress cement / prevent escape around cup

- metal insert to gauge position on xray

 

Types

- Smith & Nephew Reflection all Poly

- Styker Exeter X3 all Poly

- Zimmer ZCA all Poly

 

 

Stryker X3Reflection

Exeter X3                                                                 S&N Reflection

 

Results

 

Cemented ZCA cup

 

Australian Joint Registry 2023 Revision rates by fixation (400,000 THA)

 

  Cemented Uncemented Hybrid
5 year 2.6 3.0 2.6
10 year 3.8 4.3 3.9
15 year 5.1 5.9 5.3
20 year   7.0 6.7

 

15 year revision rate by age

 

FixationAJR

64 - 74 year                                                                                  > 75 years

 

  Cemented Uncemented Hybrid
< 55   6.4 7.2
55 - 64 6.2 5.5 6.1
65 - 74 5.4 5.5 5.2
> 75 3.3 6.8 4.7

 

Technique cemented cup

 

Stryker Exeter X3 All Poly cemented cup technique PDF

 

Stryker X3 cupStryker X3

 

 

Technique

- identify floor by removing osteophyte / reaming medially /  or can use 2.5 mm drill and measure floor depth

- ream in increased sized until fits in AP diameter

- need to remove all cortical bone, can do so with smaller reamer

- many drill holes required superiorly, this is the area where good interdigitation is critical and important

- drill holes in ischium and superior pubic rami as per Charnley

- dry acetabulum with swabs and peroxide

- place reamings with spoon at inferior acetabular ligament and compress, this prevents cement leaking inferiorly

- trial cup

- can use cup with peripheral poly lip / flange to pressurise, can be cut to size

- insert ball of cement when no longer sticky

- compress till 5 minutes, twist pressuriser to remove

- dry blood with swab on a stick

- insert cup on insertion device

- place inferior cup first, medialize +++, then set closure and anteversion

 

Complications

 

Cement

 

Inferior cementTHR Cemented Exeter Inferior Cement LeakTHR Cemented Exeter Medial Cement Penetration

Inferior cement                                     Inferior cemented                      Intra-pelvic cement

 

Loosening

 

Signs

- obvious migration in comparison previous films

- cement mantle fracture

- progressive > 2 mm lucency

 

Cemented Cup 3 Zone LysisCemented Cup Lysis Zone 1

 

Charnley zones

1 - superior 1/3

2 - middle 1/3

3 - inferior 1/3



Charnley Zones