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Periprosthetic Fractures
Lisa K. Cannada MD
Disclosures
• Member: MAOA BOD• Research Grant Monies
Goals
• Learn decision making for periprosthetichip and knee fractures:–When to treat non-operatively–When to fix–When to revise
Overall
• Periprostheticfractures are increasing
• Very difficult to treat• Treatment can violate
the tenant of care “early mobilization”
Problems
• Patients are even more frail than hip fracture patients
• Many w/multiple comorbidities
• Are deconditioned from previous surgery
• Surgery can be difficult
Periprosthetic fractures
• Metabolic workup is very important
• Team Approach• Consider anabolic
supplementation
Vancouver Classification: PPFX Hip
• A: Trochanteric fractures• B: Around prosthesis
–1 intact stem–2 loose stem–3 with osteolysis and loose stem
• C. Below prosthesis
Vancouver A fractures
• Greater or lesser trochanter
• Often non operative• Reasons for surgery:
–hip dislocation–displacement– stem unstable
Trochanteric Fixation Options
• Cable plate• Don’t put cables on
the prosthesis• Constrained liner
Vancouver B1 and C: Stem stable
• Determine is B1/C or B2/3
• Is the stem really stable?• Loosening is thought to
be under diagnosed• X-rays are often poor
• 321 patients in 1999-2000• Swedish National Hip Arthroplasty
Register• 91 after revision: 51% loose stem• 220 after primary: 66% loose stem• 13% mortality at one year• 66 mo survival rate of implant was 74%
How to assess stability• Gold standard: Changes on radiographs
over time• Lucencies around implant• Subsidence• Cement breakage• Implants with poor track records• History of painful joint replacement
Loose or stable?
• Cemented
• Cement fracture
• Implant subsidence
Loose
Loose or stable?
• Uncemented
• Subsidence
• Lucency
Loose
Loose or stable?
• No lucency
• No subsidence
• Appears ingrown
Stable
Vancouver B1 and C Fixation:NOT LOOSE
• Reduction and internal fixation
• Limited approach if possible– Curved locking plate– Screws around the
implant– Cerclage
Plan your fixation
• To bridge or not to bridge
• Absolute or relative stability
• Don’t do both!
Preop planning
• Plan placement of screws–Locking versus non
locking• Think about the stiffness
of the construct• Long working length
• Cadaveric study for B1 periprostheticfemur fractures
• Long plate vs short plate• No differences in plate length or working
length• Bone density was biggest factor
Preop planning• Care in use of locking
plates• Plan placement of
screws & screw type• Long working length• Decide if you are
bridging• Good x-rays
Plating
• Make the plate as long as possible
• Consider non locking screws angled around the stem
• Use cables if necessary
B1 fractures• Oblique
–Reduce fracture –Get bony apposition
• Transverse–Troublesome–Difficult to tell when
healed–High stress on fixation
Vancouver C
• Fracture is below the prosthesis
• Prosthesis is stable
• Bridging plate fixation
Treatment: B1 oblique and C
• Condylar plate fixation distally
Additional screws around implant
Vancouver B1 with transverse fracture
• Difficult to treat with plate
• Consider stem revision• Sometimes this is very
difficult
Fix or Revise??
Intercalary fractures
• Use the implants you have in place
• Be creative• Overlap implants• Span the entire
bone
Vancouver B2/3
• Stem is loose• Revision THA
necessary• Bypass the
fracture with a long stem
Determine why stem is loose
• Is there in infection?• Validity of ESR and
CRP with fracture?• Aspiration if high
suspicion• Culture and frozen
section intra-op
Revision: Hip Posterior
• Posterior approach• Low index for an
extended trochanteric osteotomy
• Know the type of cup and have a liner available to upsize if possible
Revision
• Depends on amount of bone stock
• Achieve distal fixation• Cemented: proximal
replacement• Uncemented: conical fluted
stem• Total femur
Fractures About the Knee
Fractures around the knee
• Femur (Most)• Patella• Tibia
Initial X Ray
Traction View How to know if the implant is stable
• Lucencies around prosthesis
• Subsidence• Osteolysis• Not the same as hip
Unified classification system
• A. Implants are stable, minor fracture• B1. Implants stable• B2. Implants loose• B3. Implants loose and severe osteolysis• C. Fracture is away from prosthesis
How to know if you can fix?
• How many fracture pieces?
• How distal is the fracture?
• What implant?• Consider CT scan
Treatment algorithm: Femur
• Non operative: stable implants and fracture
• Fixation-Plating: work horse
• Revision replacement: distal femoral replacement
Non operative
• Implants must be stable• Well aligned fracture• Patient will not tolerate
surgery
Plating
• Implants are not loose• Enough bone to
achieve distal fixation• Pre op Planning• WB decision
IM rod
• Implants are not loose• Enough bone to fix
distally• CR implant wear box is
big enough to place a rod through implant
Revision
• Loose implants• No distal bone• Need for
immediate weight bearing?
Distal Femoral Replacement• Pluses:
–Relatively straightforward
– Immediate weight bearing
• Minuses–Rotating hinge–Problem if this needs to
be revised
Distal Femoral Replacement• Tips:
–Mark center of rotation on the femur before removing bone
–Often biggest challenge is rotation
–Use one sided sagittal saw to cut tibialimplant
–Try not to lengthen leg
Tibial fractures with stable implants: non op treatment
Tibial fractures
• Plating versus non op• Can reduction be
maintained in cast or brace• If not consider plating• IMN for adventurous and
right indication
Tibial fractures
• Loose implants• Revision surgery
–Stem fixation distally–Supplemental plating
IMN CaseExample
Patella fracture
• Beware….• Most are due to AVN of the
patella–Previous lateral release–Poor rotational
alignment • These due poorly with
surgery
Surgical treatment
• Removal of implant• Is rotational
alignment of wrong?• Rare fixation of
fracture –Use supplemental
fixation with cable
If the extensor mechanism is broken
• If aligned well consider non operative treatment
• Consider fixation if displaced and unable to reduce
• May need extensor allograft reconstruction or fusion
What is worse?
Retrospective, age and gender matched• 106 PP 12 died = 11%• 309 hip fx 51 died = 17%• 311 THA/TKA 9 died = 2.9%
Vancouver B
• 49 revision arthroplasty–6 died = 12%
• 24 ORIF–8 died = 33%
• Thus, if feasible, revision arthroplasty treatment preferred
• Retrospective• 291 patients• Mortality = 13%
–Contributing factors unmodifiable• Rate of reoperation = 12%
–Decreased w/greater span of fixation–Decreased w/revision arthroplasty
• Ideal treatment unclear• Retrospective, 70 and older• 38 patients
–82 average age–10 DFR–28 ORIF
ORIF Not as Promising
• No difference in mortality• 10% reoperation rate in DFR
–All ambulatory at 1 year• 11% reoperation ORIF
–24 weeks TTU–18% Nonunion–23% WC bound at 1 year
• Retrospective, 58 patients–ORIF and DFR
• Average age: 80 (61-95)• Follow up: 30 mos (5-81)• DFR patients older: 83 v. 75• 20.5% mortality• Age > 85 predictive of ambulatory status
and living situation
Pitfalls
• Make sure implants are stable
• Make sure it is not infected
• Plan your internal fixation
• Surgery is big (1-2L blood loss)
Pitfalls
• Evaluate and treat osteoporosis
• Difficult to tell if a fracture has healed
• When to start weightbearing?
• 54 fractures/52 patients• Retrospective• 38 returned to pre injury ambulatory
status• 3 implant failures, 1 nonunion, 2
malunion• 10 thromboembolic events
• Conclusion: Immediate WB acceptable• Take home lessons:
–Early mobilization did not decrease DVT/PE (19%)
–7/54 (13%) fracture/implant issues–70% to previous ambulatory status
Case Example
Healed
If It Does Not Heal
ConstructConstruct
What If It Does Not Heal?
• What about the biology?• What could have been done better?
Teaching/Learning
• Pre op planning• Ok to shorten• Don’t make too stiff• Tons of screw not necessary
• 88 patients• All osteoporotic• Peri-implant fractures after
bone union in 5%• Stiffness/screw selection
matters
Heavy Metal: When All Else Fails
Conclusions
• Plan your surgery
• Get good fixation but not too stiff
• Determine stem stability
• Know when to revise and when to refer
Parting Thoughts
Pass It On and Give Back
• Help those behind you• Make the path easier• Never forget those who
helped you• Always lead by
example
Imitation…
Thank [email protected]
MC
• 87 yo F• CC: Transfer after fall from standing• PMHx: Hypertension• SHx: R THA in 2011• R TKA x2 revisions with DFR in 2013• ppfx with plate 2016• Painful since last 2 surgeries• lives at home, community ambulator