Uncemented Hemispherical Cups
Joshua S. Bingham
Robert T. Trousdale
Several options are available for acetabular reconstruction in the revision setting, including cementless hemispherical components, impaction grafting, reconstruction cages or rings, hemispherical cups with augments, cemented all-polyethylene components, and custom implants.
Although multiple options are available, the great majority of acetabular reconstructions can be successfully performed using an uncemented hemispherical component with screw supplemental augmentation.
This surgical technique is straightforward and should be familiar to most arthroplasty surgeons. The mid- and long-term results have been good.
Excellent long-term results have been reported with uncemented hemispherical cups in the revision setting (Table 25.1).
Highly porous metal implants with enhanced frictional coefficient against bone and high bone-ingrowth potential have expanded the indications for this form of reconstruction.
Alternative forms of acetabular reconstruction should be considered in cases with severe segmental bone loss, in cases with a pelvic discontinuity, and in situations in which obtaining bone ingrowth is challenging.
Sterile Instruments and Implants
Routine hip retractors.
Hand-guided curved acetabular osteotomes for implant removal if required.
A curved osteotome explant system for implant removal if needed.
Broken screw removal set if screws are present in previous reconstruction.
Power burr with pencil tip and carbide attachments.
Sequential hemispherical reamers.
Cancellous particulate allograft.
Either a fully porous coated hemispherical multihole revision acetabular component (with instrumentation) or a highly porous titanium or tantalum cup. For complex revisions consider using a tantalum cup that allows the surgeon to bore supplement screw holes.
Appropriately sized acetabular screws with a tap and instrumentation.
Full array of bearing options including highly cross-linked polyethylene inserts of different inside diameters with different lateralized or elevated rim options. When instability is a concern, modular dual-mobility implants may be considered.
Table 25.1 ▪ Results of Cementless Acetabular Reconstruction in Revision Total Hip Arthroplasty
The patient is placed in a lateral decubitus position, which allows for a more extensile exposure if needed.
Draping should allow for adequate access to the proximal pelvis and entire femur.
The preferred approach of the authors in the majority of revision total hip arthroplasties (THAs) is a posterior approach. The posterior approach allows access to the posterior column and the ability to perform an extended femoral osteotomy if needed. However, anterolateral approaches also are compatible with this technique (as are direct anterior approaches for surgeons expert at the approach in very selected cases).
The skin incision is partly dictated by the previous incisions, but ideally, a lateral incision is used, centered over the posterior trochanter and curving posteriorly proximally.
You may also need