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PERIPROSTHETIC FEMORAL FRACTURES AFTER THA Emmanuel Illical, Adult Reconstruction Fellow Dr. Paul Beaule MD, FRCSC. CASE PRESENTATION. 81 F w/ left THA ~ 10 years ago for post-traumatic arthritis No peri- or post-op complications from 1* THA
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PERIPROSTHETIC FEMORAL FRACTURESAFTER THAEmmanuel Illical, Adult Reconstruction FellowDr. Paul Beaule MD, FRCSC
CASE PRESENTATION • 81 F w/ left THA ~ 10 years ago for post-traumatic arthritis • No peri- or post-op complications from 1* THA • Ground level mechanical fall at home onto left side • Immediate pain left hip / thigh and unable to weight bear • AVSS • Closed, dNVI, isolated injury • Prior to fall left hip functioning well
CASE PRESENTATION Treatment options?
CASE PRESENTATION • 3 Accord cables w/ Stryker Restoration Modular: • 265 mm distal stem • 21 std proximal body • 36 mm diameter, -5 mm length femoral head • Poly exchange
CASE PRESENTATION • 77 M underwent revision right THA 1998-11-04 for aseptic loosening • No peri- or post-op complications • Ground level mechanical fall at home onto left side • Immediate pain left hip / thigh and unable to weight bear • AVSS • Closed, dNVI, isolated injury • Prior to fall: • mild occasional thigh pain • had been followed q6-12 months radiographically since 2009
CASE PRESENTATION 2005-05-09 2011-04-07
CASE PRESENTATION Treatment options?
CASE PRESENTATION • 4 Accord cables w/ Zimmer Revitan: • 260 x 22 mm distal stem w/ three distal locking screws • 75 mm conical proximal body • 36 mm diameter, -3.5 mm length femoral head • Poly liner exchange
OUTLINE • Classification • Vancouver • Defining a “loose” stem • Background • Incidence • Risk factors • Burden of disease • Management • Based on Vancouver classification • Ottawa experience • Summary: management principles
VANCOUVER CLASSIFICATION A B1 B2 B3 C
WHAT IS A “LOOSE” STEM? • Clinical signs • thigh pain • “start up” pain • Radiographic signs • always compare w/ baseline study! • progressive and extensive widening of interfaces • bone-cement or cement-prosthesis, bone-prosthesis • > 2 mm, endosteal scalloping, bead shedding • fragmentation / fracture of cement mantle • PRIOR to acute fracture = loose • in setting of acute fracture = not necessarily loose • migration / subsidence of component
BACKGROUND: INCIDENCE • Intra-operative vs. Post-operative • Intra-operative incidence varies on fixation method used • 1* THA: cemented stems: 0.1-1% vs. uncemented stems: 5.4% • Revision THA: cemented stems 3.6% vs. uncemented stems 20.9% • Post-operative incidence increasing but difficult to estimate • Patient demographics, number of revised patients, type of fixation, f/u routines • Largest data from Mayo Clinic Joint Registry: • 1.1% after 23 980 1* THA vs. 4% after 6349 revision THA • Swedish Registry data • 0.4% after 1* THA vs. 2.1% for revision THA
BACKGROUND: RISK FACTORS • Trauma • Low vs. high energy and “spontaneous” fractures • Age • multifactorial: bone quality (osteoporosis), previous surgery, co-morbidities • Gender • multifactorial: osteoporosis, more F undergoing THA, age (F > M when age > 80) • Index diagnosis • RA, hip fracture • Osteolysis / Aseptic Loosening • multiple studies demonstrate > 50% of fracture cases loose prior to fracture • Revision • rate of fracture directly related to number of revisions undertaken • average time interval to fracture w/ each revision • Implants / Technique • cemented vs. uncemented; varus malposition; any factor that bone strength
BACKGROUND: BURDEN OF DISEASE • Lindahl et al. JOA 2004 (Swedish National Registry): high morbidity • Mean hospital stay = 21 days • Peri/post-operative complication rate = 18% • Bleeding > early dislocation > superficial wound infection > death > medical > vascular / nerve injury • Re-operation = 23% • Lindahl et al. JOA 2004 & Bone 2007: significant mortality • 9.4% mortality in first 12 months post-op • Estimated probably of death • At age 70: men = 2.1%, women = 1.2% • At age 80: men = 2.9%, women = 2.2%
MANAGEMENT: TYPE A • Ag • usually related to wear debris osteolysis of GT • stable when minimally displaced (digastric complex holds in place) • protected WB to avoid displacement / provide environment for healing • displaced with adequate bone stock ORIF • trochanteric clamp, wires, cerclage with lateral plate extension • avoids pain, weakness, limp, possible instability • limited bone purchase on trochanteric fragments / poor bone quality may compromise results • Al • reflect poor bone quality / osteolytic processes • difficult to reduce / adequately fix • treat non-operatively unless distal extension involving medial cortex that destabilizes stem
MANAGEMENT: TYPE C • Fixation technique based on fracture pattern and location • Lateral based plate fixation • Locking technology / MIPO techniques can facilitate biologically friendly and mechancially stable construct • Augment with cortical strut allograft • Avoid stress risers between proximal end of plate and distal end of femoral implant • Span fixation around distal aspect of stem by at least 2 cortical diameters
MANAGEMENT OPTIONS: TYPE B1 • B1 fractures = most variable treatment options & high failure rates • Non operative (protected WB, traction, casting / bracing) • Historical higher morbidity / mortality compared to surgery • Cerclage wire / cables • up to 50% failure rate in literature • Plating options (compression / locking / cable-plate implants) • 0-48% failure rate in literature depending on type of plate fixation • Multiple reasons for high rate of failure: • inadequate fixation (torsional instability) leading to implant loosening / re-fracture • insufficient by-pass of fracture site • insufficient span of plate fixation over components • stress risers • varus malposition of femoral stems • misclassification of B2 fractures as B1
MANAGEMENT ISSUES: TYPE B1 • Biomechanical studies have shown combining lateral plate + anterior cortical strut graft = most stable construct • clinical case series also have shown good results • disadvantages: cost, availability, disease transmission, soft tissue stripping, loss of endosteal healing potential, bulk (soft tissue irritation / cable pain) • some authors have questioned degree of stability needed for fracture union • Corten et al. JBJS Br 2009 • lateral plate and cable construct + anterior strut allograft only if anatomic reduction of medial cortex could not be achieved • 33 B1 fractures: 30 treated w/ plate alone; 3 treated w/ plate + graft • 29/30 treated w/ plate alone (96.7%) united at a mean interval of 6.4 months (3 to 30) • one had pain free delayed union which eventually united at 30 months w/o further intervention • one plate failure due to insufficient proximal fixation • no implant had to be revised for loosening
MANAGEMENT ISSES: TYPE B1 • Lindahl et al. JBJS Br 2006 (Swedish registry data) • 1049 patients w/ periprosthetic fracture: 44.5% re-operation during 1st year post-op • 10 year survival rate: 70% overall (73% after 1* THA; 65%% after revision THA) • factors associated w/ INCREASED risk of failure: • Vancouver B1, initial treatment: cerclage wiring (44.9%) or plate fixation (33.9%) • reasons for failure: loosening > re-fracture • factors associated w/ REDUCTION in risk of failure: • loose stem / Vancouver B2, long revision stems • initial treatment: revision or revision + ORIF • factors NOT predisposing to risk of failure: • Vancouver types A / B3 / C • misinterpretation of stability of B1 fractures
MANAGEMENT ISSES: TYPE B1 • Lindahl et al JBJS 2006: underestimation of femoral component loosening • primary THA group: 66% loose 47% unknown loose • revision THA: 49% loose 27% unknown loose • significant disagreement between radiological assessment and intra-op findings: • Vancouver B1 = 34% agreement • Vancouver B2 = 63% agreement • Vancouver B3 = 44% agreement • classification of Vancouver B periprosthetic fractures difficult • surgical exploration recommended for all patients w/ this pre-op dx
MANAGEMENT OPTIONS: TYPE B2 / B3 • REVISION arthroplasty • Long cemented stem revision • very rarely considered • useful in very osteopenic bone w/ capacious canals • Long uncemented stem revision w/ distal fixation • most effective strategy in literature • extensively coated stem for femurs w/ > 5 cm tubular diaphysis (<18 mm diameter) • fluted tapered modular stem for femoral w/ capacious canals • use allograft struts to augment bone if needed • Proximal femoral reconstruction vs. replacement • patient age / functional class • severity of bone defect
OTTAWA EXPERIENCE • Retrospective review of pts admitted w/ peri-prosthetic fracture (PPF) • Jan 2004 to June 2009 • 63 cases reviewed • 7 intra-operative fractures; 56 post-operative fractures • 24 Males (78.2 years), 39 Females (79.3 years) • Indication for index arthroplasty: • OA = 48, Fracture = 14, RA = 1 • Implant type of arthroplasty: • THA = 50, Bipolar = 6, Unipolar = 5, Revision = 2 • Stem fixation of arthroplasty: • Uncemented = 44, Cemented = 19
OTTAWA EXPERIENCE • 45/56 post-op PPF had adequate f/u • Radiographic union occurred in 37/45 (82%) • Morbidity: 8 non-unions, 7 infections
SUMMARY: MANAGEMENT PRINCIPLES • Make appropriate diagnosis • confirm stability of the femoral implant intra-operatively if in doubt • ORIF • Follow biologic fracture principles • Limit surgical dissection to minimum needed for adequate reduction and fixation • BUT need to obtain accurate fracture reduction (open or indirect means) • Use robust fixation • Absolute vs. relative stability (comminution) • Bicortical screw fixation (cement mantle can be used to obtain fixation) • Locking fixation for osteopenic bone • Cables as an adjunct (screw fixation not technically possible) • Strut allograft when medial cortex cannot be established / bone loss • Bypass distal extent of fracture by at least two cortical diameters • Avoid stress risers (span implants with length of plate) • Revision • Long uncemented stem w/ distal fixation +/- cortical strut allograft augmentation
CASE PRESENTATION PRE-OP FILMS
CASE PRESENTATION 6 WEEKS POST-OP
CASE PRESENTATION 43 MONTHS POST-OP
CASE PRESENTATION 53 MONTHS POST-OP
CASE PRESENTATION 55 MONTHS POST-OP