surgical management of osteomyelitis & infected hardware apma 7-2017 - final draft .pdf ·...
TRANSCRIPT
Surgical Management of
Osteomyelitis & Infected
HardwareMichael L. Sganga, DPM
Orthopedics New England
Natick, MA
Disclosures
• None relevant to the content of this
material
Overview
• Implants
• Timing
• Tenants of Treatment
– Debridement
– Hardware: stability & removal• Exchange, Ex-fix, Ablative resection
– Abx: ID dealings
– Closure & Dead space
– Decision making
Incidence & Type
• Trauma 2.5x more SSI than elective (Blam 2003)
• Incidence of infection: (Mouzopoulos 2011)
– Closed 1-2%
– Open up to 30%
• Open vs closed fx ankle ORIF
– 4x increased infection (SooHoo 2009)
Elective Surgery
• Retrospective 7 yr
• 555 elective cases
• 3.1% incidence SSI
– Coag +/- Staph (71% cultures)
– 87% PCN or AMP resistant
Zgonis. J Foot Ankle Surg 2004; 43(2): 97–103.
Implant Implications
• Innoculum
100,000x smaller
• Colonized implant
• Barrier to host
immune response
– Non-vascular space
• Biofilms
• Common Bugs1. Zimmerli Journal of Infectious Disease 146(4): 487-97. 1982
2. Trampuz Swiss Med Wkly 2005; 135:243-51
3. Trampuz Injury 2006; 37:S59-66
Joint
Replacement2 All Fractures3
Staph
aureus 12-23% 30%
Coag Neg
Staph 30-43% 22%
Gram Neg
Bacilli 3-6% 10%
Anaerobes2-4% 5%
Enterococci3-7% 3%
Streptococci9-10% 1%
Polymicrobial10-12% 27%
Unknown10-11% 2%
Implants, What should I Use?
• Titanium better than stainless– (Melcher, Injury 27(S3). 1996)
• Solid better than cannulated– (Cordero, JBJS 78B. 1996)
• Smooth better than porous
– (Arens, JBJS 76B. 1994)
Early Infection <2wksTiming is Everything
Delayed 2-10wks
Late >10wks
• Colonized at time of
surgery
• Hematogenous
seeding:
• Non-articular
hardware 7%
When Things Go Wrong
• Primary objectives:– Eliminate infection
– Promote osseous union
– Optimize function
– Keep in mind objectives of intended
original procedure (IOP)
• Treatment merges:– Antimicrobial therapy
– Surgical management: debridement, deadspace, soft tissue
– Osseous stabilization
5 Foundations of Treatment
1. Identify organism
2. Excise nonviable tissueOncologic resection
3. Stability
4. Control infection: culture-driven
5. Soft tissue & dead space management
Identify Organism
• Debridement & Irrigate (9L)
• Procure cultures
– Histopath, micro: bone & tissue
– 2 samples from each site
• 2 weeks off abx is best
• HW culture or sonication if removed
– Have lab hold cultures for 2 weeks
• Sinus unreliable
My Set-up
Debridement
• 3 scenarios:
1. Large defect & unstable implant
2. Healed bone, stable after implant removal
3. Bone is not healed, implant stable
• Assess intra-op stability of bone &
hardware
Importance of Stability
• Unstable fractures more likely to develop infection– Compared infection rates of unfixated vs fixated fxs (Merritt 1987)
• Stable fixation better than unstable fixation in osteomyelitis prevention
– Staph inoculated fixation, unstable fixation double the risk of infection of stable fixation (Worlock 1994)
• Fracture healing can proceed “normally” with rigid fixation– No difference in time to union b/w infected & uninfected fxs with rigid fixation
(Friedrich 1977)
• Why is 4-6 weeks is the “earliest” for implant removal – After soft callus formation→stability adequate to prevent shortening
(Sarmiento 1995)
When to Keep Hardware
• 68-86% success with HW retention
• Infection <3 wks
• No sinus or abscess
• Pathogen is sensitive
• Stability is key at this point
When to Cut Losses
• Difficult to treat organisms
• Unstable hardware/union site
• Large bone defect
• Implant >4wks
– stability
• Sinus tract
Difficult to Treat Organisms
Rifampin resistant staphylococcus
Small-colony variant staphyloccus
Enterococci
Quinolone-resistant Pseudomonas
aeruginosa
Candida
Multidrug resistant organisms
Dead Space
Antibiotic Cement
Local antibiotic delivery
Concentrations >200x IV
Low systemic toxicity
Absorbable cement can be used as well
w/out need for removal
Getting it Closed
• VAC, STSG, HW removal, Primary closure
• Synthetic/Amnion grafts
• Plastics: Flaps
• Vascular: Amp
Chronic Osteomyelitis
• Inadequately treated acute infection
• Late problem of open fracture
• Soft tissue spread
– Immunosuppressed
– Malnourished, DM, HIV
• Sinus tract
– Send for biopsy
• ?SCC
Take-Home Principles
• Patients with early wound drainage
– I and D with intra-operative culture
– Keep implants
– Culture specific antibiotics
– Get it healed & closed
• Can get wound healing and fracture
healing in setting of infection
Who’s the Boss?
• IDSA: The ultimate decision regarding
surgical management should be made by
the surgeon with appropriate consultation
(eg, infectious diseases, plastic surgery)
as necessary