A modified technique to extract fractured femoral stem in revision total hip arthroplasty: A report of two cases

AbstractINTRODUCTIONThe removal of well-fixed broken femoral component and cement mantle can be extremely demanding, time consuming and potentially damaging to the host bone. Different methods have been described to extract broken femoral stem yet this remains one of the most challenging prospect to the revision hip surgeon.PRESENTATION OF CASEThe authors present two cases underwent a modified sliding cortical window technique utilising a tungsten carbide drill, Charnley pin retractor and an orthopaedic mallet to aid extraction of a fractured cemented femoral stem in revision total hip arthroplasty.DISCUSSIONThe modified technique offers a simple and controlled method in extracting a well fixed fractured cemented femoral stem. It has the advantage of retaining the cement mantle with subsequent good seal of the femoral cortical window secured with cable ready system. Furthermore, tungsten carbide drill bit and Charnley pin retractor are relatively readily available to aid the extraction of the broken stem. Finally, it yields the option of implanting a standard femoral stem and obviates the need for bypassing the cortical window with long revision femoral component.CONCLUSIONFractured femoral stem is a rare yet a complex and very demanding prospect to both patients and hip surgeons. The sliding cortical window technique utilising tungsten carbide drill and Charnley pin retractor is technically easy and most importantly; preserves host bone stock with cement-in-cement revision hip arthroplasty. We believe this technique can be added to the armamentarium of revision hip surgeon when faced with the challenge of extracting a fractured cemented femoral stem

Molecular events in tendinopathy: a role for metalloproteases.

Disorganized, haphazard ineffective healing is a constant feature of chronic tendinopathy. Normal tendon is composed mostly of type I collagen. Tendinopathic tendons, conversely, have a greater proportion of type III collagen, which is associated with tendon rupture. Matrix metalloproteinases (MMPs) are involved in remodelling of the extracellular matrix (ECM) of tendons, because they are either up- or down-regulated in tendinopathy. A balance between MMPs and tissue inhibitors of metalloproteinases is required to maintain tendon homeostasis. The mechanism of activation of MMPs is poorly understood, and their precise role in tendinopathy is unclear