Uncemented Hemispherical Cups



Uncemented Hemispherical Cups


Joshua S. Bingham

Robert T. Trousdale



Key Concepts



  • 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.


Implants



  • 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











































Author (y)


No. of Hips


Follow-up in Years (Range)


Results


Della Valle et al. (2005)


138


17 (15-19)


2.2% of aseptic loosening, 96% survivorship at 15 y


Templeton et al. (2001)


61


12.9 (11.5-14.3)


3.5% were radiographically loose at last follow-up


Paprosky et al. (1994)


147


5.7 (3-9)


4.1% rate of failure, all failures in 3B acetabulums


Jamali et al. (2004)


63


11 (5-17)


5% rate of aseptic loosening


Hallstrom et al. (2004)


188


12 (10-17)


11% aseptic loosening, 96% survivorship at 12 y


Leopold et al. (1999)


138


10.5 (7-14)


1.8% radiographically loose at last follow-up


Silverton et al. (1996)


138


8.3 (7-11)


0.7% failure rate at last follow-up



Positioning



  • 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.


Surgical Approaches

Dec 14, 2019 | Posted by in ORTHOPEDIC | Comments Off on Uncemented Hemispherical Cups

Full access? Get Clinical Tree

Get Clinical Tree app for offline access