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Anterior extended greater trochanteric osteotomy
Anterior Extended Greater Trochanteric Osteotomy Daniel J. Berry, MD A family of extended greater trochanteric osteotomies have been described, all of which provide excellent access to the intramedullary canal of the proximal femur. Anterior extended osteotomy is designed to elevate a fragment of the anterolateral femur in continuity with the anterior greater trochanter. The fragment is kept vascular by attachments of the anterior abductors and the anterior vastus lateralis. A technique of performing this osteotomy method is described. This osteotomy is particularly helpful for insertion of long uncemented stems with a distal straight tapered geometry. Semin Arthro 15:126-129 © 2004 Elsevier Inc. All rights reserved. KEYWORDS extended greater trochanteric osteotomy, revision total hip arthroplasty, prosthesis removal
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evision hip arthroplasty has made many advances in the last decade; chief among them have been better exposures and improved implant fixation. A family of extended greater trochanteric osteotomies have markedly improved exposure in revision total hip arthroplasty. Extended greater trochanteric osteotomies can improve speed of femoral implant removal and/or cement extraction, facilitate new implant insertion, and simultaneously preserve muscle integrity. Heinz Wagner is credited with developing an extended greater trochanteric osteotomy, which he used to efficiently remove failed implants and to facilitate insertion of a long straight uncemented fluted tapered revision femoral component. Diagrams in one early paper appear to demonstrate a lateral extended osteotomy1 but he also advocated an anterior extended osteotomy (Fig. 1).2 Subsequently Paprosky popularized a modification of the method that included a posterior approach to the hip and lateral extended greater trochanteric osteotomy (Fig. 1).3-6 As fluted tapered stems have gained a role in the armamentarium of surgeons performing revision total hip arthroplasty around the world, the value of anterior extended osteotomy has been recognized more widely. Despite frequent use of the method in Europe, it is unfamiliar to many North American surgeons. The goal of this article is to review indications and describe techniques of performing this osteotomy.
From the Mayo Clinic, Rochester, MN. Address reprint requests to Author: Daniel J. Berry, MD, Mayo Clinic, 200 First Street SW, Rochester, MN 55905.
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1045-4527/04/$-see front matter © 2004 Elsevier Inc. All rights reserved. doi:10.1053/j.sart.2004.08.008
Indications The most common reason to perform anterior extended greater trochanteric osteotomy is to facilitate removal of the failed femoral component and implantation of a tapered fluted stem. Femoral canal preparation for fluted tapered uncemented stems requires a straight reamer. A key to success of tapered fluted stems is milling of the femoral shaft to a tapered cone, which provides axial support for the implant. When a long stem is implanted, elevating the anterior proximal femur with an osteotomy allows access anteriorly to the bowed femoral canal with a long straight reamer thereby allowing the surgeon to adequately fill the femoral canal but still reduce risk of distal anterior cortical perforation (Fig. 2). An anterior extended osteotomy also may be used when extended osteotomy is needed and the surgeon wishes to preserve the maximum amount of soft tissue attachments around the posterior hip joint in hopes of minimizing the risk of posterior hip dislocation.
Method The anterior osteotomy is designed to elevate a fragment of the anterolateral proximal femur in continuity with the anterior greater trochanter. The fragment is kept vascular by attachments of the anterior abductors and the anterior aspect of the proximal vastus lateralis. The abductors are split proximally to about 4 cm above the tip of the greater trochanter, and the hip is dislocated anteriorly.
Incision The patient may be positioned in the lateral decubitus or supine position. A straight lateral skin incision is made from
Anterior extended greater trochanteric osteotomy
Figure 1 Differences between anterior extended greater trochanteric osteotomy and lateral extended greater trochanteric osteotomy. Outline of anterior extended greater trochanteric osteotomy (solid lines), outline of lateral extended greater trochanteric osteotomy (dotted lines).
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Figure 3 The posterior cortical limb of anterior extended osteotomy is created with a saw.
Osteotomy about 10 cm proximal to the tip of the greater trochanter to about 5 cm distal to the planned distal limb of the osteotomy.
Muscular Exposure The iliotibial band is divided in the direction of its fibers and the interval between the tensor fascia lata and gluteus maximus is incised. Adhesions between the fascial layer and the underlying vastus lateralis, greater trochanter, and abductors are lysed. The abductors are split in line with their fibers from the tip of the greater trochanter to about 4 cm proximally. More proximal splitting of the abductors is avoided to protect the superior gluteal nerve, which provides abductor innervation. The anterior one-half of the vastus lateralis is split in line with its fibers from the vastus tubercle to the planned distal extent of the osteotomy. At the planned level of the distal transverse osteotomy a small Hohman retractor is placed over the anterior femur. About 3 cm of femur is exposed by elevation of the vastus lateralis muscle at this level. Otherwise the vastus lateralis attachments to the femur and planned osteotomy fragment are carefully preserved to maintain blood supply to the fragment.
Figure 2 Anterior extended osteotomy allows straight reamers to be used with less likelihood of distal anterior perforation of the bowed femur.
The lateral femur is osteotomized longitudinally with a saw from the tip of the greater trochanter to the planned level of transverse distal osteotomy (Fig. 3). This osteotomy line represents the “posterior” vertical limb of the osteotomy, even though it is directly lateral in the femur. The distal transverse osteotomy is made with a small high-speed cutting tool or a saw. If a saw is used, a small burr is used to complete rounded corners for the osteotomy to avoid stress risers that could predispose to femur fracture (Fig. 4). The goal is for the osteotomy fragment to encompass about one-third of the circumference of the femur. The hip is externally rotated to gain access to the anterior femur. A saw is used to create a short anterior vertical osteotomy limb, starting at the anterior aspect of the distal transverse limb and working about 2 cm proximally. This short osteotomy helps ensure that the anterior vertical limb of the osteotomy will terminate in the correct position. Next a line of perforations is made with a drill or osteotome to define the anterior vertical limb of the osteotomy (Fig. 5). The drill or narrow osteotome is introduced through the muscle of the anterior vastus lateralis and abductors. Care is taken to avoid damaging the neurovascular structures (femoral vessels and femoral nerve). The perforations should be in line with the distal anterior vertical osteotomy previously created with a saw. Broad osteotomes then are introduced through the more posterior vertical longitudinal osteotomy and the osteotomy fragment is gently and repetitively ele-
Figure 4 The distal corners of the osteotomy are created with a thin, high-speed cutting instrument to produce rounded corners.
D.J. Berry
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Figure 5 The anterior osteotomy is outlined with a line of perforations made by insertion of a drill or osteotomies through muscle into the bone.
vated until the anterior vertical limb of the osteotomy is completed by controlled fracture along the perforation line (Fig. 6). Osteotomy elevation should be done carefully and gradually to avoid fracture of the osteotomy fragment. After the osteotomy fragment is elevated, the fragment (in continuity with anterior abductors and the vastus lateralis) is translated anteriorly. The anterior hip pseudocapsule is incised or excised. Posterior and superior hip capsule and posterior abductors may be preserved. The leg is placed in an anterior pocket if the procedure is being performed in a lateral decubitus position. The hip is dislocated anteriorly by external rotation. The failed hip stem and any cement are removed (Fig. 7). Canal preparation and acetabular preparation are completed and acetabular and femoral components are inserted. During this process the leg should be manipulated gently to avoid fracture of the femur (which is tethered proximally by the posterior abductors) at the level of the greater trochanter or a weak point in the osteotomized region. The osteotomy fragment is reapproximated to its bed with cerclage wires or cables (usually two or three in number) (Fig. 8). If autologous bone graft from reamings is available, it is packed along the osteotomy site. Proximally the anterior greater trochanter may be approximated to the posterior greater trochanter with transosseous wires or heavy suture passed through drill holes in bone (Fig. 8). The abductors are closed with heavy interrupted sutures. The vastus lateralis is
Figure 6 The osteotomy is elevated carefully with large osteotomies completing the anterior vertical limb of the osteotomy as a controlled fracture.
Figure 7 The anterior osteotomy fragment is translated anteriorly and the hip is dislocated anteriorly to allow extraction of the femoral component in the cement.
closed in routine fashion and layered wound closure is performed. Postoperatively protected weightbearing usually is recommended for at least 8 weeks.
Pitfalls Failure to complete the distal transverse osteotomy to the depth of the implant can lead to a crack in the femur that extends distal to the osteotomy. Creating rounded corners of the distal osteotomy may reduce femur fracture risk during manipulation of the femur and during implant insertion. The osteotomy fragment can be fractured when it is being elevated away from the proximal femur; gentle progressive mobilization of the osteotomy fragment can reduce this risk. The osteotomy fragment also can be fractured by retractors after it has been elevated. Leaving old cement attached to the fragment until just before reattachment may reduce this risk. The posterior greater trochanter or femoral shaft can fracture during manipulation of the femur after the osteotomy has been performed because it is tethered to the pelvis by scar, muscle, and hip capsule. Caution during limb manipulation may reduce this risk. Devascularization of the osteotomy fragment by excessive muscle stripping should avoided, as vascularity of the fragment promotes healing.
Figure 8 Fixation of the anterior extended greater trochanteric osteotomy.
Anterior extended greater trochanteric osteotomy
Results Despite widespread use in Europe and increasing use worldwide, the author has been unable to identify any reports that specifically evaluate the healing rate or complications associated with anterior extended greater trochanteric osteotomy.
Conclusion Anterior extended greater trochanteric osteotomy provides excellent exposure of proximal femoral canal and facilitates insertion of certain uncemented femoral components in revision total hip arthroplasty.
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References 1. Wagner H: Revisionsprothese für das Hüftgelenk. Orthopäde 18:438453, 1989 2. Wagner, H: Uncemented Self-locking Revision Stem for Extensive Bone Loss. Bern, Switzerland: Protek, 1991, p 19 3. Aribindi R, Paprosky W, Nourbash P et al: Extended proximal femoral osteotomy. Instr Course Lect 48:19-26, 1999 4. Miner TM, Momberger NG, Chong D, et al: The extended trochanteric osteotomy in revision hip arthroplasty: A critical review of 166 cases at mean 3-year, 9-month follow-up. J Arthroplasty 16:188-194, 2001 5. Younger TI, Bradford MS, Magnus RE, et al: Extended proximal femoral osteotomy: A new technique for femoral revision arthroplasty. J Arthroplasty 10:329-338, 1995 6. Chen WM, McAuley JP, Engh CA Jr, et al: Extended slide trochanteric osteotomy for revision total hip arthroplasty. J Bone Joint Surg 82A: 1215-1219, 2000
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evision hip arthroplasty has made many advances in the last decade; chief among them have been better exposures and improved implant fixation. A family of extended greater trochanteric osteotomies have markedly improved exposure in revision total hip arthroplasty. Extended greater trochanteric osteotomies can improve speed of femoral implant removal and/or cement extraction, facilitate new implant insertion, and simultaneously preserve muscle integrity. Heinz Wagner is credited with developing an extended greater trochanteric osteotomy, which he used to efficiently remove failed implants and to facilitate insertion of a long straight uncemented fluted tapered revision femoral component. Diagrams in one early paper appear to demonstrate a lateral extended osteotomy1 but he also advocated an anterior extended osteotomy (Fig. 1).2 Subsequently Paprosky popularized a modification of the method that included a posterior approach to the hip and lateral extended greater trochanteric osteotomy (Fig. 1).3-6 As fluted tapered stems have gained a role in the armamentarium of surgeons performing revision total hip arthroplasty around the world, the value of anterior extended osteotomy has been recognized more widely. Despite frequent use of the method in Europe, it is unfamiliar to many North American surgeons. The goal of this article is to review indications and describe techniques of performing this osteotomy.
From the Mayo Clinic, Rochester, MN. Address reprint requests to Author: Daniel J. Berry, MD, Mayo Clinic, 200 First Street SW, Rochester, MN 55905.
126
1045-4527/04/$-see front matter © 2004 Elsevier Inc. All rights reserved. doi:10.1053/j.sart.2004.08.008
Indications The most common reason to perform anterior extended greater trochanteric osteotomy is to facilitate removal of the failed femoral component and implantation of a tapered fluted stem. Femoral canal preparation for fluted tapered uncemented stems requires a straight reamer. A key to success of tapered fluted stems is milling of the femoral shaft to a tapered cone, which provides axial support for the implant. When a long stem is implanted, elevating the anterior proximal femur with an osteotomy allows access anteriorly to the bowed femoral canal with a long straight reamer thereby allowing the surgeon to adequately fill the femoral canal but still reduce risk of distal anterior cortical perforation (Fig. 2). An anterior extended osteotomy also may be used when extended osteotomy is needed and the surgeon wishes to preserve the maximum amount of soft tissue attachments around the posterior hip joint in hopes of minimizing the risk of posterior hip dislocation.
Method The anterior osteotomy is designed to elevate a fragment of the anterolateral proximal femur in continuity with the anterior greater trochanter. The fragment is kept vascular by attachments of the anterior abductors and the anterior aspect of the proximal vastus lateralis. The abductors are split proximally to about 4 cm above the tip of the greater trochanter, and the hip is dislocated anteriorly.
Incision The patient may be positioned in the lateral decubitus or supine position. A straight lateral skin incision is made from
Anterior extended greater trochanteric osteotomy
Figure 1 Differences between anterior extended greater trochanteric osteotomy and lateral extended greater trochanteric osteotomy. Outline of anterior extended greater trochanteric osteotomy (solid lines), outline of lateral extended greater trochanteric osteotomy (dotted lines).
127
Figure 3 The posterior cortical limb of anterior extended osteotomy is created with a saw.
Osteotomy about 10 cm proximal to the tip of the greater trochanter to about 5 cm distal to the planned distal limb of the osteotomy.
Muscular Exposure The iliotibial band is divided in the direction of its fibers and the interval between the tensor fascia lata and gluteus maximus is incised. Adhesions between the fascial layer and the underlying vastus lateralis, greater trochanter, and abductors are lysed. The abductors are split in line with their fibers from the tip of the greater trochanter to about 4 cm proximally. More proximal splitting of the abductors is avoided to protect the superior gluteal nerve, which provides abductor innervation. The anterior one-half of the vastus lateralis is split in line with its fibers from the vastus tubercle to the planned distal extent of the osteotomy. At the planned level of the distal transverse osteotomy a small Hohman retractor is placed over the anterior femur. About 3 cm of femur is exposed by elevation of the vastus lateralis muscle at this level. Otherwise the vastus lateralis attachments to the femur and planned osteotomy fragment are carefully preserved to maintain blood supply to the fragment.
Figure 2 Anterior extended osteotomy allows straight reamers to be used with less likelihood of distal anterior perforation of the bowed femur.
The lateral femur is osteotomized longitudinally with a saw from the tip of the greater trochanter to the planned level of transverse distal osteotomy (Fig. 3). This osteotomy line represents the “posterior” vertical limb of the osteotomy, even though it is directly lateral in the femur. The distal transverse osteotomy is made with a small high-speed cutting tool or a saw. If a saw is used, a small burr is used to complete rounded corners for the osteotomy to avoid stress risers that could predispose to femur fracture (Fig. 4). The goal is for the osteotomy fragment to encompass about one-third of the circumference of the femur. The hip is externally rotated to gain access to the anterior femur. A saw is used to create a short anterior vertical osteotomy limb, starting at the anterior aspect of the distal transverse limb and working about 2 cm proximally. This short osteotomy helps ensure that the anterior vertical limb of the osteotomy will terminate in the correct position. Next a line of perforations is made with a drill or osteotome to define the anterior vertical limb of the osteotomy (Fig. 5). The drill or narrow osteotome is introduced through the muscle of the anterior vastus lateralis and abductors. Care is taken to avoid damaging the neurovascular structures (femoral vessels and femoral nerve). The perforations should be in line with the distal anterior vertical osteotomy previously created with a saw. Broad osteotomes then are introduced through the more posterior vertical longitudinal osteotomy and the osteotomy fragment is gently and repetitively ele-
Figure 4 The distal corners of the osteotomy are created with a thin, high-speed cutting instrument to produce rounded corners.
D.J. Berry
128
Figure 5 The anterior osteotomy is outlined with a line of perforations made by insertion of a drill or osteotomies through muscle into the bone.
vated until the anterior vertical limb of the osteotomy is completed by controlled fracture along the perforation line (Fig. 6). Osteotomy elevation should be done carefully and gradually to avoid fracture of the osteotomy fragment. After the osteotomy fragment is elevated, the fragment (in continuity with anterior abductors and the vastus lateralis) is translated anteriorly. The anterior hip pseudocapsule is incised or excised. Posterior and superior hip capsule and posterior abductors may be preserved. The leg is placed in an anterior pocket if the procedure is being performed in a lateral decubitus position. The hip is dislocated anteriorly by external rotation. The failed hip stem and any cement are removed (Fig. 7). Canal preparation and acetabular preparation are completed and acetabular and femoral components are inserted. During this process the leg should be manipulated gently to avoid fracture of the femur (which is tethered proximally by the posterior abductors) at the level of the greater trochanter or a weak point in the osteotomized region. The osteotomy fragment is reapproximated to its bed with cerclage wires or cables (usually two or three in number) (Fig. 8). If autologous bone graft from reamings is available, it is packed along the osteotomy site. Proximally the anterior greater trochanter may be approximated to the posterior greater trochanter with transosseous wires or heavy suture passed through drill holes in bone (Fig. 8). The abductors are closed with heavy interrupted sutures. The vastus lateralis is
Figure 6 The osteotomy is elevated carefully with large osteotomies completing the anterior vertical limb of the osteotomy as a controlled fracture.
Figure 7 The anterior osteotomy fragment is translated anteriorly and the hip is dislocated anteriorly to allow extraction of the femoral component in the cement.
closed in routine fashion and layered wound closure is performed. Postoperatively protected weightbearing usually is recommended for at least 8 weeks.
Pitfalls Failure to complete the distal transverse osteotomy to the depth of the implant can lead to a crack in the femur that extends distal to the osteotomy. Creating rounded corners of the distal osteotomy may reduce femur fracture risk during manipulation of the femur and during implant insertion. The osteotomy fragment can be fractured when it is being elevated away from the proximal femur; gentle progressive mobilization of the osteotomy fragment can reduce this risk. The osteotomy fragment also can be fractured by retractors after it has been elevated. Leaving old cement attached to the fragment until just before reattachment may reduce this risk. The posterior greater trochanter or femoral shaft can fracture during manipulation of the femur after the osteotomy has been performed because it is tethered to the pelvis by scar, muscle, and hip capsule. Caution during limb manipulation may reduce this risk. Devascularization of the osteotomy fragment by excessive muscle stripping should avoided, as vascularity of the fragment promotes healing.
Figure 8 Fixation of the anterior extended greater trochanteric osteotomy.
Anterior extended greater trochanteric osteotomy
Results Despite widespread use in Europe and increasing use worldwide, the author has been unable to identify any reports that specifically evaluate the healing rate or complications associated with anterior extended greater trochanteric osteotomy.
Conclusion Anterior extended greater trochanteric osteotomy provides excellent exposure of proximal femoral canal and facilitates insertion of certain uncemented femoral components in revision total hip arthroplasty.
129
References 1. Wagner H: Revisionsprothese für das Hüftgelenk. Orthopäde 18:438453, 1989 2. Wagner, H: Uncemented Self-locking Revision Stem for Extensive Bone Loss. Bern, Switzerland: Protek, 1991, p 19 3. Aribindi R, Paprosky W, Nourbash P et al: Extended proximal femoral osteotomy. Instr Course Lect 48:19-26, 1999 4. Miner TM, Momberger NG, Chong D, et al: The extended trochanteric osteotomy in revision hip arthroplasty: A critical review of 166 cases at mean 3-year, 9-month follow-up. J Arthroplasty 16:188-194, 2001 5. Younger TI, Bradford MS, Magnus RE, et al: Extended proximal femoral osteotomy: A new technique for femoral revision arthroplasty. J Arthroplasty 10:329-338, 1995 6. Chen WM, McAuley JP, Engh CA Jr, et al: Extended slide trochanteric osteotomy for revision total hip arthroplasty. J Bone Joint Surg 82A: 1215-1219, 2000