Indications
Tumour / metastatic
Severe osteoporosis / elderly
Pagets
Design
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
Exeter X3 S&N Reflection
Results
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
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
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 cement Inferior cemented Intra-pelvic cement
Loosening
Signs
- obvious migration in comparison previous films
- cement mantle fracture
- progressive > 2 mm lucency
Charnley zones
1 - superior 1/3
2 - middle 1/3
3 - inferior 1/3