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Orthopaedic Proceedings
Vol. 97-B, Issue SUPP_13 | Pages 89 - 89
1 Nov 2015
Ries M
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The Vancouver classification separates periprosthetic femur fractures after THA into three regions (A - trochanteric, B - around or just below the stem, and C - well below the stem), with fractures around or just below the stem further separated into those with a well-fixed (B1) or loose stem and good (B2) or poor (B3) bone stock. Trochanteric fractures may be associated with osteolysis and require treatment that addresses osteolysis as well as ORIF of displaced fractures. Fractures around a well-fixed stem can be treated with ORIF using cerclage or cable plating, while those around a loose stem require implant revision usually to a longer cementless tapered or distally porous coated cementless stem. Fractures around a loose stem with poor bone stock in which salvage of the proximal femur is not possible require replacement of the proximal femur with an allograft prosthetic composite or proximal femoral replacement. Fractures well below the stem can be treated with conventional plating methods. Periprosthetic acetabular fractures are rare and usually occur in the early post-operative period or late as a result of osteolysis or trauma. These can generally be separated into those with a stable acetabular component which can be treated non-operatively, and those with an unstable component often with discontinuity or posterior column instability which require complex acetabular reconstruction utilizing plating or revision to a cup-cage


Orthopaedic Proceedings
Vol. 100-B, Issue SUPP_10 | Pages 63 - 63
1 Jun 2018
Paprosky W
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The unacceptable failure rate of cemented femoral revisions led to many different cementless femoral designs employing fixation in the damaged proximal femur with biological coatings limited to this area. The results of these devices were uniformly poor and were abandoned for the most part by the mid-1990's. Fully porous coated devices employing distal fixation in the diaphysis emerged as the gold standard for revisions with several authors reporting greater than 90% success rate 8–10 years of follow-up. Surgical techniques and ease of insertion improved with the introduction of the extended trochanteric osteotomy as well as curved, long, fully porous coated stems with diameters up to 23mm. The limits of these stems were stretched to include any stem diameter in which even 1–2cm of diaphyseal contact could be achieved. When diaphyseal fixation was not possible (Type IV), the alternatives were either impaction grafting or allograft prosthetic composite (APC). As the results of fully porous coated stems were very carefully scrutinised, it became apparent that certain types of bone loss did not yield the most satisfactory results both clinically and radiographically. When less than 4cm of diaphyseal press fit (Type IIIB) was achieved, the mechanical failure rate (MFR) was over 25%. It also became apparent that even when there was 4–6cm diaphyseal contact (Type IIIA), and the stem diameter was 18mm or greater, post-operative pain and function scores were significantly less than those with smaller diameter stems. This was probably due to poorer quality bone. Many of these Type IIIA and Type IIIB femurs had severe proximal torsional remodeling leading to marked distortion of anteversion. This made judging the amount of anteversion to apply to the stem at the time of insertion very difficult, leading to higher rates of dislocation. These distortions were not present in Type I and Type II femurs. This chain of events which was a combination of minimal diaphyseal fixation, excessively stiff stems and higher dislocation rates led to the conversion to modular type stems when these conditions existed. For the past 13 years, low modulus taper stems of the Wagner design have been used for almost all Type IIIA and Type IIIB bone defects. The taper design with fluted splines allows for fixation when there is less than 2cm of diaphysis. The results in these femurs even with diameters of up to 26mm have led to very low MFRs and significantly less thigh pain. Independent anteversion adjustment is also a huge advantage in these modular stems. Similar success rates, albeit with less follow-up, have been noted in Type IV femurs


Orthopaedic Proceedings
Vol. 99-B, Issue SUPP_15 | Pages 94 - 94
1 Aug 2017
Sierra R
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The technique involves impaction of cancellous bone into a cavitary femur. If segmental defects are present, the defects can be closed with stainless steel mesh. The technique requires retrograde fill of the femoral cavity with cancellous chips of appropriate size to create a new endomedullary canal. By using a set of trial impactors that are slightly larger than the real implants the cancellous bone is impacted into the tube. Subsequent proximal impaction of bone is performed with square tip or half moon impactors. A key part of the technique is to impact the bone tightly into the tube especially around the calcar to provide optimal stability. Finally a polished tapered stem is cemented using almost liquid cement in order to achieve interdigitation of the implant to the cancellous bone. The technique as described is rarely performed today in many centers around the world. In the US, the technique lost its interest because of the lengthy operative times, unacceptable rate of peri-operative and post-operative fractures and most importantly, owing to the success of tapered fluted modular stems. In centers such as Exeter where the technique was popularised, it is rarely performed today as well, as the primary cemented stems used there, rarely require revision. There is ample experience from around the globe, however, with the technique. Much has been learned about the best size and choice of cancellous graft, force of impaction, surface finish of the cemented stem, importance of stem length, and the limitations and complications of the technique. There are also good histology data that demonstrate successful vascularization and incorporation of the impacted cancellous bone chips and host bone. Our experience at the clinic was excellent with the technique as reported in CORR in 2003 by M Cabanela. The results at mid-term demonstrated minimal subsidence and good graft incorporation. Six of 54 hips, however, had a post-operative distal femoral fracture requiring ORIF. The use of longer cemented stems may decrease the risk of distal fracture and was subsequently reported by the author after reviewing a case series from Exeter. Today, I perform this technique once or twice per year. It is an option in the younger patient, where bone restoration is desired. Usually in a Paprosky Type IV femur, where a closed tube can be recreated and the proximal bone is reasonable. If the proximal bone is of poor quality, then I prefer to perform a transfemoral osteotomy, and perform an allograft prosthetic composite instead of impaction grafting, and wrap the proximal bone around the structural allograft. I prefer this technique as I can maintain the soft tissues over the bone and avoid the stripping that would be required to reinforce the bone with struts or mesh. Another indication for its use in the primary setting is in the patient with fibrous dysplasia


Orthopaedic Proceedings
Vol. 96-B, Issue SUPP_8 | Pages 97 - 97
1 May 2014
Haidukewych G
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Vancouver A: If minimal displacement and prosthesis stable can treat nonoperatively. If displacement is unacceptable and/or osteolysis is present consider surgery. AL: Rare, avulsions from osteopenia and lysis. If large, displaced and include large portion of calcar-can destabilise stem and prompt femoral revision. AG: More common. Often secondary to lysis. Does not usually affect implant stability. Minimal displacement. Treat closed × 3 months. Revise later is needed to remove the particle generator, debride defects and bone graft. Displaced with good host bone stock. Consider early ORIF and bone grafting. Vancouver B:. B1: Rarely non-operative. ORIF with femoral component retention. Need to carefully identify stem fixation. B2's classified as B1's are doomed to fail. B1's correctly identified treated with plate, allograft struts or both. High union rates with component retention. B2: Femoral revision +/− strut allograft. Best results seen with patients revised with uncemented, extensively porous coated femoral stems. May use modular, fluted taper stems. B3: Proximal femoral replacement - Tumor prosthesis, Allograft Prosthetic Composite (APC). Uncemented femoral stem - Extensively porous coated, Fluted, tapered stem, Allograft strut. Vancouver C: Treat with standard fracture techniques. These fractures are away from the femoral prosthesis. Rarely nonoperative. Fixation options – Cerclage, Strut Allograft, Plate fixation, Retrograde IM nail, or a Combination thereof. Avoid stress risers between implants. Bypass (overlap) fixation. Consider allowing 2.5 cortical diameters between devices


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_22 | Pages 57 - 57
1 May 2013
Paprosky W
Full Access

The unacceptable failure rate of cemented femoral revisions led to many different cementless femoral designs employing fixation in the damaged proximal femur with biological coatings limited to this area. The results of these devices were uniformly poor and were abandoned for the most part by the mid 1990's. Fully porous coated devices employing distal fixation in the diaphysis emerged as the gold standard for revisions with several authors reporting greater than 90% success rate at 8–10 years of follow-up. Surgical techniques and ease of insertion improved with the introduction of the extended trochanteric osteotomy as well as curved, long, fully porous coated stems with diameters up to 23 mm. The limits of these stems were stretched to include any stem diameter in which even 1–2 cm of diaphyseal contact could be achieved. When diaphyseal fixation was not possible (Type IV), the alternatives were either impaction grafting or allograft prosthetic composite (APC). As the results of fully porous coated stems were very carefully scrutinised, it became apparent that certain types of bone loss did not yield the most satisfactory results both clinically and radiographically. When less than 4 cm of diaphyseal press fit (Type IIIB) was achieved, mechanical failure rate (MFR) was over 25%. It also became apparent that even when there was 4–6 cm. diaphyseal contact (Type IIIA), and the stem diameter was 18 mm or greater, post-op pain and function scores were significantly less than those with smaller diameter stems. This was probably due to poorer quality bone. Many of these Type IIIA and Type IIIB femurs had severe proximal torsional remodeling leading to marked distortion of anteversion. This made judging the amount of anteversion to apply to the stem at the time of insertion very difficult, leading to higher rates of dislocation. These distortions were not present in Type I and Type II femurs. This chain of events which was a combination of minimal diaphyseal fixation, excessively stiff stems and higher dislocation rates led to the conversion to modular type stems when these conditions existed. For the past 8 years, low modulus taper stems of the Wagner design have been used for almost all Type IIIA and Type IIIB bone defects. The taper design with fluted splines allows for fixation when there is less than 2 cm of diaphysis. The results in these femurs even with diameters of up to 26 mm have led to very low M.F.R.'s and significantly less thigh pain. Independent anteversion adjustment is also a hug advantage in these modular stems. Similar success rates, albeit with less follow-up, have been noted in Type IV femurs