Revision Shoulder Replacement
The demand for joint replacements are growing. Latest projections show that the demand for shoulder replacement will grow by between 192% and 322% by 2015 (1). With this will steady increase will come an inevitable increase in the revision burden.
Shoulder replacements can fail for many reasons but the most common non-infective causes are:
- Loosening of the prosthesis over time (usually the glenoid - called aseptic loosening)
- Progressive wear of the glenoid after hemiarthroplasty (when just the humerus was replaced or resurfaced)
- Rotator cuff tears leading to abnormal biomechanics
Contained glenoid defect
Contained defects are suitable for a technique called impaction grafting. Impaction grafting has been show to a successful technique leading to increased bone stock and implant stability in the hip (2). The addition of autologous marrow had been shown to increase incorporation rates (3) and the development of the technique to use custom tamps has improved success (4). At the Wrightington Upper Limb Unit we have developed technique of impaction grafting for use in contained defects of the glenoid, based upon these lessons (5). Our original technique utilised a cemented keeled glenoid component however this relies exclusively on incorporation of the impacted bone graft and the integrity of the bone cement interface for long-term stability. The advent of newer materials will hopefully improve this technique by encouraging bone to incorporate with the prosthesis for long-term stability. Trabecular Titanium (TT) is a very complex 3D metal structure. TT has been shown to be both oseteoconductive and osteoinductive. This means that it not only forms a good scaffold for bone to grow into but also actually stimulates new bone formation. The most modern glenoid components are now made out of this new material we can use for glenoid revision surgery.
If the glenoid bone loss leads to an uncontained defect then this poses much more of a reconstructive challenge as we cannot rely on the native bone to support an implant. Usually in this situation the humeral head has moved along way medially which means that the force of deltoid is also very reduced. In this situation we need to use bone from elsewhere to form a structural graft. The best bone come from your own body and we try a use part of the hip bone called the iliac crest if possible. In rare cases that this is not suitable we can use donated hip bone called allograft. This type of surgery is very challenging and has a high rate of complications. It is therefore only performed in a few centres in the UK by very specialised surgeons.
Bulk Iliac Crest Graft with Glenoid Base Plate
The bone is only part of the deficiency in revision shoulder replacement surgery and the soft-tissues of the rotator cuff are also usually damaged. The reverse shoulder replacement, which can be used without relying on the rotator cuff tendons, is therefore frequently used in revision surgery.
- Day JS, Lau E, Ong KL, Williams GR, Ramsey ML, Kurtz SM. Prevalence and projections of total shoulder and elbow arthroplasty in the United States to 2015. J Shoulder Elbow Surg. 2010 Dec;19(8):1115-20. Epub 2010 Jun 15.
- Lamberton TD, Kenny PJ, Whitehouse SL, Timperley AJ, Gie GA. Femoral impaction grafting in revision total hip arthroplasty: a follow-up of 540 hips. J Arthroplasty. 2011 Dec;26(8):1154-60. Epub 2011 May 13.
- Deakin DE, Bannister GC. Graft incorporation after acetabular and femoral impaction grafting with washed irradiated allograft and autologous marrow. J Arthroplasty. 2007 Jan;22(1):89-94
- Howie DW, Callary SA, McGee MA, Russell NC, Solomon LB. Reduced femoral component subsidence with improved impaction grafting at revision hip arthroplasty. Clin Orthop Relat Res. 2010 Dec;468(12):3314-21.
- Page RS, Haines JF, Trail I. Impaction bone grafting in revision shoulder arthroplasty: classification, technical description and early results. Shoulder & Elbow. 2009;1:81-88