simple & comprehensive approach for infected THR management

1. MANAGEMENT OF INFECTED
TOTAL HIP REPLACEMENT
PRESENTER : DR VENKATESH
MODERATOR : DR GUNNAIAH K G

2. Introduction
• Postoperative infection is a difficult
complication
• It is painful, disabling, costly, often requiring
removal of both components, and is
associated with a reported mortality rate of
2.5%

3. In modern days
1. Advances in understanding of patient
selection
2. The operating room environment
3. Surgical technique
4. The use of prophylactic antibiotics have
dramatically reduced the risk

4. Higher incidence
1. Diabetes
2. Rheumatologic disease
3. Obesity
4. Coagulopathy
5. Corticosteriods
6. Preoperative anemia/sickle cell disease.
7. Prolonged operative time and previous hip
surgery.

5. Causative Organism

6. MECHANISM INVOLVED IN INFECITION
1. Direct contamination of the wound at the
time of surgery
2. Local spread of superficial wound infection
3. Hematogenous spread of distant bacterial
colonization / infection from a separate site
4. Reactivation of latent hip infection in a
previously septic joint.

7. ANTI-BIOTIC PROPHYLAXIS
• Infections are caused by gram-positive
organisms, particularly coagulase-negative
staphylococci and Staphylococcus aureus
• MR SA & Pseudomonas aeruginosa is mainly
because of presence of glycocalyx extension in
the cell wall.

8. Guidelines

9. Classification of Infection post
operatively
TSUKAYAMA CLASSIFICATION ::
1. Early postoperative infection: onset within 1 M
2. Late chronic infection: onset more than 1 M ,insidious onset.
3. Acute hematogenous infection—onset more than 1 month
after surgery, acute onset of symptoms, distant source of infection
4. Positive intraoperative cultures: positive cultures obtained
at the time of revision for supposedly aseptic condition

10. • Extended classification by Trampuz & Zimmerli
1. Early Infection : upto 3 M Post Op.
2. Delayed Infection : 3 M – 24 M
3. Late Infection : > 24 M
• Senneville Classification : timing of infection
Acute < 1 M :::: Late > 1 M.

11. DIAGNOSIS
• Diagnosis of early postoperative infection or
acute hematogenous infection is often not
difficult.
• Late chronic infection is difficult for diagnosis
– clue – well functioning arthroplasty with
pain not subsiding.

12. • History of excessive wound drainage after the
initial arthroplasty
• multiple episodes of wound erythema
• prolonged antibiotic treatment by the
operating surgeon also are worrisome.
• Lab reports : ESR – 30mm/hr , CRP – 10mg/l
are sensitive & specific

13. • Normal pt- ESR may take upto 1 yr for
normalisation.
• But CRP should normalize with in 3 weeks
after replacement.
• Aspiration not undertaken until after 2 weeks
of stopping antibiotics.

14. • Arthrogram : which showed Pseudobursae
periosteal ossification
Sinus tracks.

15. • Ideal scenario for diagnosis =
• when abnormal ESR and CRP are found in
combination with an aspirate WBC count
greater than 3000 leukocytes/ml.

16. • Radionucleotide study for infected THR
1. Nuclear medicine studies may be obtained if the
diagnosis : not confirmed by hip aspiration but
still high index of suspicion remains.
2. The combination of indium labeled leukocyte
and technetium sulfur colloid-labeled marrow
imaging seems to be more reliable.

17. International Consensus on
Periprosthetic Infection Guidelines
1) Two positive periprosthetic cultures with
phenotypically identical organisms, or
2) sinus track communicating with the joint, or
3) Having three of the following minor criteria:
■ Elevated serum (CRP) and (ESR)
■ Elevated synovial fluid (WBC) count
or change on leukocyte esterase test strip
■ Elevated synovial fluid neutrophil% (PMN%)
■ Positive histologic analysis of periprosthetic tissue
■ A single positive culture

18. MANAGEMENT PRINICIPLES
1. Antibiotic therapy
2. Debridement and irrigation of the hip with
component retention
3. Debridement and irrigation of the hip with
component removal
4. One-stage or two-stage reimplantation of total
hip arthroplasty
5. Arthrodesis
6. Amputation

19. MANAGEMENT DEPENDS ON ::
• Chronicity
• Virulence
• Status of wound
• Surrounding soft tissues

20. DECISION FOR COMPONENT
RETENTION OR REMOVAL
• < 2 WEEKS OF
PRESENTATION since
onset of symptoms
• Debridement +
retention
• > 2 WEEKS OF
PRESENTATION since
onset symptoms
• Debridement +
component removal

21. EARLY POSTOPERATIVE INFECTION
• Early infections may range in severity from
superficial cellulitis (antibiotics) to deep
infections (surgical management).
• Decision making for medical / surgical line of
management = EXTENSION OF INFECTION
BELOW THE DEEP FASCIA.

22. • Surgery required if – wound dehiscence/ skin
necrosis/ infected hematoma + .
• If joint is infected superficially then take the
joint is to be opened in OT. The wound is
opened down to the deep fascia, and the
structures are examined carefully to see
whether the infection extends beneath it.

23. • If the infection is superficial
the wound is thoroughly
irrigated with large quantities
of a physiologic solution
containing antibiotics, and all
necrotic subcutaneous tissue
and skin are excised.
• If the infection extends to the
hip joint, the wound debrided
and irrigated with an antibiotic
solution.
• The hip must be dislocated to
perform this procedure
thoroughly,
• if modular components have
been implanted,liner and
femoral head are exchanged to
limit the previously
contaminated foreign bodies
• Wounds are closed over the
drains.

24. • Cultures of joint fluid or other fluid collections
encountered along with tissue cultures from
the superficial, deep and periprosthetic layers
are sent for analysis of the offending organism
and antibiotic sensitivities.

25. LATE CHRONIC INFECTION
• Surgical debridement and component
removal are required if eradication of the
infection is to be done.
• Sinus tracks are debrided
• Nonabsorbable sutures and trochanteric
hardware are removed.
• The hip is dislocated, and all infected and
necrotic material is excised.

26. • The femoral and acetabular components and any
other foreign material, including cement, cement
restrictors, cables or wires are removed.
• One recommendation for non removal of well
fixed femoral component because removal causes
more bone loss.
• c/s of synovium, necrotic tissue is sent
• If antibiotic-containing beads or spacers have
been placed, some authors have recommended
that drains not be used to maintain a high
concentration of antibiotic in the wound

27. ACUTE HEMATOGENOUS INFECTION
• The hip becomes acutely painful long after the
index operation.
• The infection may have been caused by
hematogenous spread from a remote site of
infection or from transient bacteremia caused
by an invasive procedure.

28. • C/F :: Pain on weight bearing, on motion of
the hip, and at rest is the chief symptom of
acute hematogenous infection.
• Lab : ESR & CRP = +
• Diagnosis established by joint aspiration.
• Joint aspirate fluid shows raised WBC counts,
positive cultures & relevant sensitivity.

29. • While reports on cultures are being done,
broad-spectrum antibiotics = against gram-
positive and gram-negative organisms are
administered.
• More aggressive approach includes complete
removal of components and immediate
reimplantation with primary cementless
components.

30. RECONSTRUCTION AFTER INFECTION
• Decision making in reimplanting a new
prosthesis –
1. Functional impairment of pt
2. Infecting organism
3. Adequacy of debridement
4. Control local & distant infection

31. • Re-implantation done in
1. One stage/ Direct exchange
2. Two stage / Delayed exchange

32. • Delayed re-implantation is advantageous :
1. The adequacy of debridement is ensured
because repeat debridement of soft tissues
is done.
2. Infecting organism identified & treatment
started
3. Foci of infection can be identified
4. Distant infection can be eradicated
5. Decision regarding resection plasty can be
done (depending on degree of disability).

33. • One-stage exchange is done =
• when effective antibiotics are available and
systemic symptoms of sepsis are absent.
• Contra indicn : sinus tract + , soft tissue
compromise

34. • Two stage is indicated : septic pts, sinus tracts,
unidentified organism , compromised soft tissues.
• Re- implantation with cement or cementless is
guided by –
available bone stock
physiologic age
expected longevity of pt

35. Duncan and Beauchamp 2 stage Techn
• Tech in which a prosthesis of antibiotic
loaded acrylic cement (PROSTALAC) is
implanted at the time of the initial
debridement.
• The prosthesis is constructed intraoperatively
by molding antibiotic-laden cement around a
femoral component and an all-polyethylene
acetabular component.

36. • Components are
Interfernce fit ,
simplifying while
Extraction.

37. • Current guidelines for re- implantation :
1. 6 weeks of antibiotics
2. ESR & CRP negative
3. Repeat hip aspiration negative reports
4. Reconstruction done at 3 months interval.

38. • Restoration of limb length & full motion shouldn’t
be expected
• If trochanteric osteotomy is done then limb
lengthened & abductor weakness is present.
• Iliopsoas & gluteus maximus tendon release may
be needed for hip reduction.

39. • If acetabular anterior or post wall is thin, it
may be fractured by over sized implants
• Femoral canal prepared avoiding fractures ,
by placing prophylactically cerclage wires.
• Frozen sections of tissues can be examined for
residual inflammation.

40. GIRDLE STONE ARTHROPLASTY
• Using standard approach head of femur ,
neck, greater trochanter is exposed
completely.
• Here head, neck , GT , infected synovium are
removed , thorough debridement done skin
closed.
• Followingly patient is put on skeletal traction
of = 3-10 kg for 6 weeks.
• Followed by mobilization.

41. LOOSENING OF IMPLANTS
• Femoral and acetabular loosening are some of
the most serious long-term complications of
total hip arthroplasty and commonly lead to
revision.
• Some studies define failure as radiographic
evidence of loosening despite continued
satisfactory clinical performance.

42. Zones

43. FEMORAL LOOSENING
CEMENTED FEMORAL COMPONENT LOOSENING
1. Radiolucency b/w gruen zone 1 =
debonding of stem from cement & early
stem deformation.
2. Radiolucency between the cement mantle
and surrounding bone

44. 3. Subsidence of stem or with cement mantle
4. Femoral stem becoming varus position
5. Fragmentation in gruen zone 7
6. Fragmentation of cement in gruen 4
7. Deformation of stem
8. Fracture of stem.

45. Harris, McCarthy, and O’Neill defined femoral
component loosening radiographically :
definite loosening
• when there is migration of the component or cement;
probable loosening
• when a complete radiolucency is noted around the
cement mantle
possible loosening
• when an incomplete radiolucency surrounding more
than 50% of the cement

46. • Mechanism of loosening in cemented
component
Debris produced because of
mechanical factors
Biological response by formation
of FIBROUS MEMBRANE B/W
cement & bone interface
Results in loosening

47. • Not all gaps are loosening ….
1. Incomplete removal of cancellous bone
2. Age related expansion of canal
3. Femoral cortex thinning
Less than 2mm lucency in gruen zone 1 is not
indicative of loosening.

48. • Stem in canal may subside due to the fracture
at the tip of the stem & the with entire
cement mantle it may subside.

49. TECHNICAL PROBLEMS THAT
CONTRIBUTE TO
STEM LOOSENING:
1. Failure to remove the soft cancellous bone
from the medial surface of the femoral neck
2. Failure to provide a cement mantle of
adequate thickness around the entire stem
3. Removal of all trabecular bone from the
canal, leaving a smooth surface with no
capacity for cement intrusion

50. 4. Inadequate quantity of cement
5. Failure to pressurize the cement, resulting in
inadequate flow of cement
6. Failure to prevent stem motion while the
cement is hardening
7. Failure to position the component in a
neutral alignment (centralized)
8. The presence of voids in the cement as a
result of poor mixing or injecting technique

51. Barrack, Mulroy, and Harris grading for
femoral cement mantle
1. Grade 1 :Complete filling of
the medullary canal
without radiolucencies
(“white-out”)
2. Grade 2 : Slight
radiolucency at the bone-
cement interface (<50%)
3. Grade 3 : Lucency
surrounding 50% to 99% of the
interface
4. Grade 4 :Complete lucency
& a defect of the mantle at the
tip of the stem

52. CEMENTLESS FEMORAL COMPONENTS
• Bobyn, and Glassman classification of fixation of
femoral stem :
• Bone ingrowth - is defined as an implant with no
subsidence and minimal or no radiopaque line
formation around the stem.
• Cortical hypertrophy near porous surface + ,
• “spot welds” between the stem and endosteum

53. • stable fibrous fixation : no progressive
migration ,
• Extensive radiopaque line forms around the
stem, femoral cortex shows no local
hypertrophy, suggesting bone has a uniform
load-carrying function

54. • unstable implant : definite evidence of
progressive subsidence or migration within
the canal. Divergent radio-opaque lines
around stem.
• Increased cortical density around collar & tip
of the stem.
• Bony pedestal at the tip indicates
pistoning/telescoping

55. • Subsidence of a cementless femoral
component early in the postoperative course
may allow the stem to attain a more stable
position within the femoral canal.
• Bone ingrowth is still possible with durable
implant fixation.

56. ACETABULAR LOOSENING
• CEMENTED ACETABULAR COMPONENTS
Changes in the pelvis and acetabular
component
1. Absorption of bone from around part or all
of the cement mantle.
2. Cephalad translation combined with sagittal
plane rotation.

57. 3. Wear of the cup, as indicated by a decrease in
the distance between the surface of the head
and the periphery of the cup.
4. Fracture of the cup and cement
• Femoral loosening occurs at stem – cement
interface , but acetabular loosening occurs at
cement – bone interface

58. • Ace loosening starts at the periphery progress
towards dome.
• Radiolucencies + horizontal
cup

59. • Technical difficulties leading to loosening :
1. Inadequate cup support –Ace not reamed
deeply/ sup & post wall deficiencies/ medial
wall deficiencies during preparation .
2. Failure to remove all of the cartilage, loose
bone fragments, fibrous tissue, and blood.
3. Failure to pressurize the cement adequately

60. 4. Failure to distribute the cement
5. Movement of the cup or cement mantle
while the cement is hardening
6. A small diameter cup would not pressurize
the cement adequately
7. Malpositioning of the cup.

61. • radiolucency of 2 mm or more in width is
present in all three zones is accepted for
loosening.

62. CEMENTLESS ACETABULAR
COMPONENTS
• Loosening of cementless, porous-coated
acetabular components is an uncommon
finding
• Engh, Griffin, and Marx classification : stable,
probably unstable & definitely unstable

63. • Diagnosis ::
1. Septic loosening produces pain on
movement, pain at rest.
2. In acetabular loosening there is a startup
pain which is worst in the first few steps .
3. Early post op pain suggest infection.

64. • Loosening diagnosis is done only on follow up
x rays which shows progressive
radiolucencies.
• Adjunctive investigations : arthrography,
nuclear medicine studies.
• Arthrography shows : layer around the ace cup
shows loosening.

65. • Thank U !!!!