Surgical Management of Osteomyelitis & Infected Hardware Michael 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 Bugs Unknown 1. 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 Replacement 2 All Fractures 3 Staph aureus 12-23% 30% Coag Neg Staph 30-43% 22% Gram Neg Bacilli 3-6% 10% Anaerobes Enterococci Streptococci Polymicrobial 2-4% 5% 3-7% 3% 9-10% 1% 10-12% 27% 10-11% 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 Timing Infection is Everything <2wks
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 tissue Oncologic 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
3 scenarios: Debridement 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
Thank You!Questi ons? Michael L. Sganga, DPM doctorsganga@gmail.com