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Management of periprosthetic fractures: The hip
The Journal of Arthroplasty Vol. 17 No. 4 Suppl. 1 2002
Management of Periprosthetic Fractures The Hip Daniel J. Berry, MD
Abstract: Treatment of periprosthetic fractures around a total hip arthroplasty is based on fracture timing (intraoperative or postoperative) and fracture location (acetabulum or femur). Most intraoperative fractures are treated by ensuring that the implant and fracture are stable and employing minor technique modifications to ensure that the fracture remains stable postoperatively. Major intraoperative fractures require more complex reconstruction. Postoperative fractures associated with well-fixed implants typically are treated with open reduction and internal fixation. Postoperative fractures associated with loose implants are treated with revision and fracture stabilization, usually with specialized revision implants. Key words: total hip arthroplasty, periprosthetic fracture, femur, acetabulum. Copyright 2002, Elsevier Science (USA). All rights reserved.
Treatment of periprosthetic fractures around a total hip arthroplasty (THA) is based on fracture timing, whether the fracture occurred intraoperatively or postoperatively, and fracture location, whether the acetabulum or the femur.
should be removed before implant impaction. In patients with poor bone quality, particularly those without arthritis of the acetabulum (such as a patient with a femoral neck nonunion), there is a heightened fracture risk. Treatment of intraoperative acetabular fractures is determined by fracture severity [1]. If the fracture is a minor crack and the implant is stable, the surgeon may elect to leave the fracture alone or to augment cup fixation with screws. For intraoperative acetabular fractures that render the pelvis unstable, the surgeon should stabilize the pelvis, with a plate if necessary, and gain stable cup fixation, either with an uncemented hemispherical cup or with an antiprotrusio cage.
Acetabular Fractures Intraoperative Fractures Most acetabular fractures occur intraoperatively during insertion of an uncemented acetabular component. Many fractures can be avoided with careful technique. The surgeon should be careful not to underream the acetabulum by ⬎2 mm in most circumstances. A rim of unreamed bone at the acetabular opening left behind during the reaming
Postoperative Fractures Postoperative acetabular fractures are infrequent and usually involve a significant episode of trauma or stress fracture through an area of marked bone loss or osteolysis. Revision surgery for these complex cases involves stabilization of the pelvis and choice of implants appropriate to manage major acetabular bone loss [2,3].
From the Department of Orthopedic Surgery, Mayo Clinic, Rochester, Minnesota. No benefits or funds were received in support of this study. Reprint requests: Daniel J. Berry, MD, Mayo Clinic, 200 First Street, SW, Rochester, MN 55905. E-mail: [email protected] Copyright 2002, Elsevier Science (USA). All rights reserved. 0883-5403/02/1704-1025$35.00/0 doi:10.1054/arth.2002.32682
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12 The Journal of Arthroplasty Vol. 17 No. 4 Suppl. 1 June 2002
Femoral Fractures Intraoperative Fractures Many intraoperative femoral fractures can be avoided by careful preoperative planning with templates to optimize implant design and size. Most fractures occur during implantation of an uncemented implant, and some can be avoided by judicious force during femoral preparation and component implantation and particular caution when working with osteopenic bone. Intraoperative femoral fractures are managed according to fracture severity [4]. Minor cracks that do not affect implant stability or femoral integrity usually can be managed intraoperatively with cerclage fixation or, if not identified until postoperatively, in some cases with limited weight bearing and observation. Femoral fractures that compromise implant stability or femoral integrity require fracture fixation with cerclage, strut grafts, or plates and may require conversion intraoperatively to a long-stem implant. Postoperative Fractures Most periprosthetic femoral fractures occur postoperatively. A treatment algorithm has been developed based on the excellent Vancouver Periprosthetic Femur Fracture Classification system [5]. Treatment is based primarily on fracture location and secondarily on implant fixation status and remaining bone quality. Fractures are divided into peritrochanteric fractures, fractures well distal to the stem tip, and fractures around the stem. Peritrochanteric Fractures. Peritrochanteric fractures associated with stable implants, acceptable fracture displacement, and no or minimal osteolysis can be treated with closed management. Markedly displaced peritrochanteric fractures or fractures that have occurred because of osteolysis usually require surgery. The main treatment tenets are to stabilize the fracture in an appropriate position and to remove the osteolysis generator, if present. If there is severe osteolysis and the remaining greater trochanter is only a thin shell, stopping osteolysis progression is the main goal of surgery. In these circumstances, it usually is best to leave the fracture and soft tissue envelope undisturbed because fracture fixation attempts often are unsuccessful, and disturbing the trochanteric shell can compromise abductor muscle function further. The greater trochanteric shell usually can be packed with cancellous bone– graft, and loose nonessential trochanteric fragments that might cause mechanical clicking symptoms can be excised.
Fractures Remote From the Stem. Fractures of the distal femur, remote from the femoral component, should be treated similar to any other femoral fracture. In most cases, treatment is with open reduction and internal fixation usually using a plate or retrograde nail. Fractures Around the Stem. Most postoperative periprosthetic fractures occur around the body or tip of the stem. There is little role for nonoperative treatment of these fractures. Nonoperative treatment has a high likelihood of malunion or nonunion [6] and requires prolonged immobilization or bed rest, which is not desirable in older patients with THA. Fractures around the stem can be divided into 3 categories: i) fractures in which the stem is well fixed and functioning well, ii) fractures in which the stem is loose, and iii) fractures in which the stem is loose with poor, nonsupportive proximal bone [5]. If the stem is well-fixed and functioning well, usually it is desirable to retain the stem and fix the fracture [5]. Because special techniques are required, fractures can be fixed with a combination of a plate and a strut graft or with strut grafts alone [7]. Plates are available that allow placement of cerclage and bicortical screws distal to the fracture and cerclage and unicortical screws proximal to the fracture. Excessive periosteal stripping should be avoided to preserve the blood supply of the femur. Autogenous bone– graft can be added to the fracture site to enhance healing. Fractures around the stem associated with a loose stem almost always are treated with femoral revision [3,8]. Each revision THA in the presence of periprosthetic fracture is different, and each requires some innovation on the part of the surgeon. Nevertheless, many key treatment principles should be followed for success: i) the failed implant is removed using the fracture to help gain access to the implant; ii) the fracture usually is bypassed with a long-stem implant; iii) stable fracture fixation is gained; iv) stable implant fixation is gained; and v) the blood supply of the femur is damaged as little as possible to enhance subsequent healing. The choice of implant fixation is at the surgeon’s discretion. Cemented and uncemented stems can work, and the decision about which type of stem to use is based on fracture pattern, patient demographics, and bone quality. Cemented stems are best reserved for older patients with simple fracture patterns in whom cement extrusion can be minimized. If cement is used, the fracture should be reduced anatomically before cementation to prevent cement from entering the fracture line and potentially causing a nonunion. For most patients, a
Periprosthetic Fracture Around THA • Daniel J. Berry
long uncemented stem, usually fixed distally, is preferred. Distally fixed stems allow the surgeon to gain implant fixation distal to the fracture in wellpreserved diaphyseal bone. After gaining distal fixation, the proximal fracture fragments can be wrapped around the proximal implant. Fractures around a loose stem with severely comminuted or unreconstructable bone usually are treated with proximal femoral substitution [5]. Either tumor prostheses or allograft prosthetic composites can be used. Alternatively, uncemented stems that are fixed distally in the bone (either a conical tapered, fluted implant or a press-fit porouscoated implant) can be used. The implant must be stable axially and rotationally in the distal femur because the proximal bone is not supportive, and must be strong enough to provide long-term load bearing without component failure.
Conclusion Most minor intraoperative fractures around a THA are treated by ensuring that the implant and fracture are stable, then using minor technique modifications to ensure that the implant and fracture remain stable in the postoperative period. Major intraoperative fractures associated with unstable implants require more complex reconstructions. Postoperative fractures associated with well-fixed implants mostly are treated with open reduction
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and internal fixation, whereas postoperative fractures associated with a loose implant are treated with revision and fracture stabilization.
References 1. Sharkey PF, Hozack WJ, Callaghan JJ, et al: Acetabular fracture associated with cementless acetabular component insertion: a report of thirteen cases. J Arthroplasty 14:426, 1999 2. Berry DJ, Lewallen DG, Hanssen AD, Cabanela ME: Pelvic discontinuity in revision total hip arthroplasty. J Bone Joint Surg Am 81:1692, 1999 3. Peterson CA, Lewallen DG: Periprosthetic fracture of the acetabulum after total hip arthroplasty. J Bone Joint Surg Am 78:1206, 1996 4. Schwartz JT, Mayer JG, Engh CA: Femoral fracture during noncemented total hip arthroplasty. J Bone Joint Surg Am 71:1135, 1989 5. Duncan CP, Masri BA: Fractures of the femur after hip replacement. Instr Course Lect 45:293, 1995 6. Bethea JS, deAndrade JR, Fleming LL, et al: Proximal femoral fractures following total hip arthroplasty. Clin Orthop 170:95, 1982 7. Haddad FS, Duncan CP, Berry DJ, et al: Periprosthetic femoral fractures around well fixed implants: an independent observer multicenter study of the use of cortical onlay allografts or cortical onlay allografts with plates. J Bone Joint Surg Am 2002 (in press) 8. Lewallen DG, Berry DJ: Periprosthetic fracture of the femur after total hip arthroplasty: treatment and results to date. J Bone Joint Surg Am 79:1881, 1997
Management of Periprosthetic Fractures The Hip Daniel J. Berry, MD
Abstract: Treatment of periprosthetic fractures around a total hip arthroplasty is based on fracture timing (intraoperative or postoperative) and fracture location (acetabulum or femur). Most intraoperative fractures are treated by ensuring that the implant and fracture are stable and employing minor technique modifications to ensure that the fracture remains stable postoperatively. Major intraoperative fractures require more complex reconstruction. Postoperative fractures associated with well-fixed implants typically are treated with open reduction and internal fixation. Postoperative fractures associated with loose implants are treated with revision and fracture stabilization, usually with specialized revision implants. Key words: total hip arthroplasty, periprosthetic fracture, femur, acetabulum. Copyright 2002, Elsevier Science (USA). All rights reserved.
Treatment of periprosthetic fractures around a total hip arthroplasty (THA) is based on fracture timing, whether the fracture occurred intraoperatively or postoperatively, and fracture location, whether the acetabulum or the femur.
should be removed before implant impaction. In patients with poor bone quality, particularly those without arthritis of the acetabulum (such as a patient with a femoral neck nonunion), there is a heightened fracture risk. Treatment of intraoperative acetabular fractures is determined by fracture severity [1]. If the fracture is a minor crack and the implant is stable, the surgeon may elect to leave the fracture alone or to augment cup fixation with screws. For intraoperative acetabular fractures that render the pelvis unstable, the surgeon should stabilize the pelvis, with a plate if necessary, and gain stable cup fixation, either with an uncemented hemispherical cup or with an antiprotrusio cage.
Acetabular Fractures Intraoperative Fractures Most acetabular fractures occur intraoperatively during insertion of an uncemented acetabular component. Many fractures can be avoided with careful technique. The surgeon should be careful not to underream the acetabulum by ⬎2 mm in most circumstances. A rim of unreamed bone at the acetabular opening left behind during the reaming
Postoperative Fractures Postoperative acetabular fractures are infrequent and usually involve a significant episode of trauma or stress fracture through an area of marked bone loss or osteolysis. Revision surgery for these complex cases involves stabilization of the pelvis and choice of implants appropriate to manage major acetabular bone loss [2,3].
From the Department of Orthopedic Surgery, Mayo Clinic, Rochester, Minnesota. No benefits or funds were received in support of this study. Reprint requests: Daniel J. Berry, MD, Mayo Clinic, 200 First Street, SW, Rochester, MN 55905. E-mail: [email protected] Copyright 2002, Elsevier Science (USA). All rights reserved. 0883-5403/02/1704-1025$35.00/0 doi:10.1054/arth.2002.32682
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12 The Journal of Arthroplasty Vol. 17 No. 4 Suppl. 1 June 2002
Femoral Fractures Intraoperative Fractures Many intraoperative femoral fractures can be avoided by careful preoperative planning with templates to optimize implant design and size. Most fractures occur during implantation of an uncemented implant, and some can be avoided by judicious force during femoral preparation and component implantation and particular caution when working with osteopenic bone. Intraoperative femoral fractures are managed according to fracture severity [4]. Minor cracks that do not affect implant stability or femoral integrity usually can be managed intraoperatively with cerclage fixation or, if not identified until postoperatively, in some cases with limited weight bearing and observation. Femoral fractures that compromise implant stability or femoral integrity require fracture fixation with cerclage, strut grafts, or plates and may require conversion intraoperatively to a long-stem implant. Postoperative Fractures Most periprosthetic femoral fractures occur postoperatively. A treatment algorithm has been developed based on the excellent Vancouver Periprosthetic Femur Fracture Classification system [5]. Treatment is based primarily on fracture location and secondarily on implant fixation status and remaining bone quality. Fractures are divided into peritrochanteric fractures, fractures well distal to the stem tip, and fractures around the stem. Peritrochanteric Fractures. Peritrochanteric fractures associated with stable implants, acceptable fracture displacement, and no or minimal osteolysis can be treated with closed management. Markedly displaced peritrochanteric fractures or fractures that have occurred because of osteolysis usually require surgery. The main treatment tenets are to stabilize the fracture in an appropriate position and to remove the osteolysis generator, if present. If there is severe osteolysis and the remaining greater trochanter is only a thin shell, stopping osteolysis progression is the main goal of surgery. In these circumstances, it usually is best to leave the fracture and soft tissue envelope undisturbed because fracture fixation attempts often are unsuccessful, and disturbing the trochanteric shell can compromise abductor muscle function further. The greater trochanteric shell usually can be packed with cancellous bone– graft, and loose nonessential trochanteric fragments that might cause mechanical clicking symptoms can be excised.
Fractures Remote From the Stem. Fractures of the distal femur, remote from the femoral component, should be treated similar to any other femoral fracture. In most cases, treatment is with open reduction and internal fixation usually using a plate or retrograde nail. Fractures Around the Stem. Most postoperative periprosthetic fractures occur around the body or tip of the stem. There is little role for nonoperative treatment of these fractures. Nonoperative treatment has a high likelihood of malunion or nonunion [6] and requires prolonged immobilization or bed rest, which is not desirable in older patients with THA. Fractures around the stem can be divided into 3 categories: i) fractures in which the stem is well fixed and functioning well, ii) fractures in which the stem is loose, and iii) fractures in which the stem is loose with poor, nonsupportive proximal bone [5]. If the stem is well-fixed and functioning well, usually it is desirable to retain the stem and fix the fracture [5]. Because special techniques are required, fractures can be fixed with a combination of a plate and a strut graft or with strut grafts alone [7]. Plates are available that allow placement of cerclage and bicortical screws distal to the fracture and cerclage and unicortical screws proximal to the fracture. Excessive periosteal stripping should be avoided to preserve the blood supply of the femur. Autogenous bone– graft can be added to the fracture site to enhance healing. Fractures around the stem associated with a loose stem almost always are treated with femoral revision [3,8]. Each revision THA in the presence of periprosthetic fracture is different, and each requires some innovation on the part of the surgeon. Nevertheless, many key treatment principles should be followed for success: i) the failed implant is removed using the fracture to help gain access to the implant; ii) the fracture usually is bypassed with a long-stem implant; iii) stable fracture fixation is gained; iv) stable implant fixation is gained; and v) the blood supply of the femur is damaged as little as possible to enhance subsequent healing. The choice of implant fixation is at the surgeon’s discretion. Cemented and uncemented stems can work, and the decision about which type of stem to use is based on fracture pattern, patient demographics, and bone quality. Cemented stems are best reserved for older patients with simple fracture patterns in whom cement extrusion can be minimized. If cement is used, the fracture should be reduced anatomically before cementation to prevent cement from entering the fracture line and potentially causing a nonunion. For most patients, a
Periprosthetic Fracture Around THA • Daniel J. Berry
long uncemented stem, usually fixed distally, is preferred. Distally fixed stems allow the surgeon to gain implant fixation distal to the fracture in wellpreserved diaphyseal bone. After gaining distal fixation, the proximal fracture fragments can be wrapped around the proximal implant. Fractures around a loose stem with severely comminuted or unreconstructable bone usually are treated with proximal femoral substitution [5]. Either tumor prostheses or allograft prosthetic composites can be used. Alternatively, uncemented stems that are fixed distally in the bone (either a conical tapered, fluted implant or a press-fit porouscoated implant) can be used. The implant must be stable axially and rotationally in the distal femur because the proximal bone is not supportive, and must be strong enough to provide long-term load bearing without component failure.
Conclusion Most minor intraoperative fractures around a THA are treated by ensuring that the implant and fracture are stable, then using minor technique modifications to ensure that the implant and fracture remain stable in the postoperative period. Major intraoperative fractures associated with unstable implants require more complex reconstructions. Postoperative fractures associated with well-fixed implants mostly are treated with open reduction
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and internal fixation, whereas postoperative fractures associated with a loose implant are treated with revision and fracture stabilization.
References 1. Sharkey PF, Hozack WJ, Callaghan JJ, et al: Acetabular fracture associated with cementless acetabular component insertion: a report of thirteen cases. J Arthroplasty 14:426, 1999 2. Berry DJ, Lewallen DG, Hanssen AD, Cabanela ME: Pelvic discontinuity in revision total hip arthroplasty. J Bone Joint Surg Am 81:1692, 1999 3. Peterson CA, Lewallen DG: Periprosthetic fracture of the acetabulum after total hip arthroplasty. J Bone Joint Surg Am 78:1206, 1996 4. Schwartz JT, Mayer JG, Engh CA: Femoral fracture during noncemented total hip arthroplasty. J Bone Joint Surg Am 71:1135, 1989 5. Duncan CP, Masri BA: Fractures of the femur after hip replacement. Instr Course Lect 45:293, 1995 6. Bethea JS, deAndrade JR, Fleming LL, et al: Proximal femoral fractures following total hip arthroplasty. Clin Orthop 170:95, 1982 7. Haddad FS, Duncan CP, Berry DJ, et al: Periprosthetic femoral fractures around well fixed implants: an independent observer multicenter study of the use of cortical onlay allografts or cortical onlay allografts with plates. J Bone Joint Surg Am 2002 (in press) 8. Lewallen DG, Berry DJ: Periprosthetic fracture of the femur after total hip arthroplasty: treatment and results to date. J Bone Joint Surg Am 79:1881, 1997