summary THA Periprosthetic Fractures are a complication of a total hip prosthesis with increasing incidence as a result of increased arthroplasty procedures and high-demands of elderly patients. Diagnosis can be made with plain radiographs of the affected hip and ipsilateral femur. Treatment may be nonoperative or operative based on location of fracture, implant stability and bone stock available. Epidemiology Incidence intraoperative fractures 3.5% of primary uncemented hip replacements 0.4% of cemented arthroplasties postoperative fractures 0.1% most common at stem tip Etiology Classification intraoperative fractures femur acetabulum postoperative fractures femur acetabulum Prevention preoperative templating reduces risk of intraoperative fractures adequate surgical exposure special care when using cementless prosthesis in poor bone (RA, osteoporosis) Intraoperative Acetabular Fractures Introduction incidence cemented acetabular components 0.2% cementless acetabular components 0.4% mechanism typically occurs during acetabular component impaction risk factors underreaming >2mm elliptical modular cups osteoporosis cementless acetabular components dysplasia radiation Evaluation must determine stability of implant Treatment observation alone indications if evaluated intraoperatively and found to be stable postoperative care consider protected weight-bearing for 8-12 weeks acetabular revision with screws vs. ORIF indications if evaluated intraoperatively and found to be unstable technique addition of acetabular screws may consider upgrading to "jumbo" cup ORIF of acetabular fracture with revision of acetabular component if posterior column is compromised, ORIF + revision is most stable construct may add bone graft from reamings if patient has poor bone stock postoperative care consider protected weight-bearing for 8-12 weeks Intraoperative Femur Fractures Introduction incidence primary THA 0.1-5% revision THA 3-21% mechanism proximal fractures usually occur with bone preparation (ie aggressive rasping) and prosthetic insertion may occur during implant insertion from dimension mismatch middle-region fractures usually occur when excessive force is used during surgical exposure or bone preparation distal fractures usually occur when tip of a straight-stem prosthesis impacting at femoral bow risk factors impaction bone grafting female gender technical errors cementless implants osteoporosis revision minimally invasive techniques (controversial) Presentation change in resistance while inserting stem should raise suspicion for fracture Classification Vancouver classification (intraoperative) considerations location pattern stability of fracture types A - proximal metaphysis B - diaphyseal C - distal to stem tip (not amenable to insertion of longest revision stem) subtypes 1 - cortical perforation 2 - nondisplaced crack 3 - displaced unstable fracture pattern Imaging intraoperative radiographs are required when there is a concern for fracture Treatment stem removal, cabling, and reinsertion indications intraoperative longitudinal calcar split trochanteric fixation with wires, cables, or claw-plate indications intraoperative, proximal femur fractures removal of implant, insertion of longer stem prosthesis indications complete (two-part) fractures of middle region technique distal tip of stem must bypass distal extent of fracture by 2 cortical diameters may use cortical allograft struts for added stability removal of implant, internal fixation with plate, reinsertion of prosthesis indications distal fractures that cannot be bypassed with a long-stemmed prosthesis Vancouver Classification & Treatment - Intraoperative Periprosthetic Fracture Type Description Treatment A1 Proximal metaphysis, cortical perforation Bone graft alone (e.g. from acetabular reaming) A2 Proximal metaphysis, nondisplaced crack Cerclage wire before inserting stem (to prevent crack propagation) Ignore the fracture if fully porous coated stem is used (provided there is no distal propagation) A3 Proximal metaphysis, displaced unstable fracture Fully porous coated stem, or tapered fluted stem Wires/cables/claw plate for isolated GT fractures B1 Diaphyseal, cortical perforation (usually during cement removal) Fully porous coated stem (bypass by 2 cortical diameters) ± strut allograft B2 Diaphyseal, nondisplaced crack (from increased hoop stress during broaching or implant placement) Cerclage wire (if implant stable) Fully porous coated stem to bypass defect (if implant unstable) ± strut allograft PWB and observation (if detected postop) B3 Diaphyseal, displaced unstable fracture (usually during hip dislocation, cement removal, stem insertion) Fully porous coated stem to bypass defect ± strut allograft C1 Distal to stem tip, cortical perforation (during cement removal) Morcellized bone graft, fully porous coated stem to bypass defect, strut allograft C2 Distal to stem tip, nondisplaced fracture Cerclage wire, strut allograft C3 Distal to stem tip, displaced unstable fracture ORIF Postoperative Femur fracture Introduction incidence 0.1-3% for primary cementless total hip arthroplasties etiology early postoperative fractures cementless prosthesis tend to fracture in the first six months likely caused by stress risers during reaming and broaching wedge-fit tapered designs cause proximal fractures cylindrical fully porous-coated stems tend to cause a distal split in the femoral shaft late postoperative fractures cemented prosthesis tend to fracture later (5 years out) tend to fracture around the tip of the prosthesis or distal to it risk factors poor bone quality cementless prostheses compromised bone stock revision procedures Classification Vancouver classification (postoperative) considerations stability of prosthesis location of fracture quality of surrounding bone pros simple validated cons often difficult to differentiate between B1 and B2 fractures based on radiographs alone Vancouver Classification & Treatment - Postoperative Periprosthetic Fracture Type Description Treatment AG Fracture in greater trochanteric region. Commonly associated with osteolysis. AG (greater trochanter) fractures caused by retraction, broaching, actual implant insertion, previous hip screws. Often requires treatment that addresses the osteolysis. AG fractures with < 2cm displacement, treat nonoperatively with partial WB and allow fibrous union. AG fractures >2cm needs ORIF (loss of abductor function leads to instability) with trochanteric claw/cables AL Fracture in lesser trochanteric region. AL fractures are commonly treated non-operatively B1 Fracture around stem or just below it, with a well fixed stem ORIF using cerclage cables and locking plates B2 Fracture around stem or just below it, with a loose stem but good proximal bone stock Revision of the femoral component to a long porous-coated cementless stems and fixation of the fracture fragment. Revision of the acetabular component if indicated B3 Fracture around stem or just below it, with proximal bone that is poor quality or severely comminuted Femoral component revision with proximal femoral allograft (APC) or proximal femoral replacement (PFR) C Fracture occurs well below the prosthesis ORIF with plate (leave the hip and acetabular prosthesis alone) Presentation often result after low-energy trauma Treatment nonoperative treatment with protected weight-bearing indications non-displaced periprosthetic fractures of greater trochanter non-displaced fractures of lesser trochanter technique limiting abduction may decrease chances of displacement with greater trochanter fractures ORIF greater trochanter with wires, cables, or claw-plate indications displaced periprosthetic fractures of the greater trochanter technique if osteolysis is present, use cancellous allograft to fill defects ORIF femoral shaft with locking plate and cerclage wires indications Vancouver B1 fractures Vancouver C fractures technique typically place cerclage wires/cables proximally and bicortical screws distal to stem may use unicortical locking screws proximally may add cortical strut allografts femoral component revision with long-stem prosthesis indications Vancouver B2 fractures some Vancouver B3 fractures femoral component revision with proximal femoral allograft indications Vancouver B3 fractures in young patients femoral component revision with proximal femoral replacement indications Vancouver B3 fractures in elderly, low-demand patients