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Title: ASEPTIC REVISION TOTAL KNEE REPLACEMENT


1
ASEPTIC REVISION TOTAL KNEE REPLACEMENT
  • Frank Ebert, MD
  • Johns Hopkins University Union Memorial Board
    Review

2
Revision Total Knee Replacement
  • Mode of failure
  • Diagnosis
  • Classification of failure
  • Reconstruction
  • Exposure
  • Reconstructive principles
  • Results

3
Mode of Failure
  • Septic vs aseptic
  • Component loosening
  • Component failure (poly)
  • Knee instability
  • Knee or component malalignment
  • Patellar tracking
  • Pain
  • Other (stiffness, RSD, trauma)

4
Diagnosis
  • History
  • Pain, instability, function
  • Duration of symptoms
  • Signs of infection
  • Examination
  • Motion
  • Instability
  • Metal on metal grinding
  • Extensor abnormalities

5
Component Loosening
  • Rule out sepsis
  • Mechanical pain vs pain at rest
  • X-rays- best asset (OKU 1995)
  • AP, lat, Merchant of patella, long leg standing
  • Old xrays
  • ?flouroscopy?

6
Laboratory Testing
  • Aspiration is essential
  • CBC, sed rate, C-reactive protein
  • Bone scan? Gallium scan? Indium scan? may be
    institution specific
  • Indium scan not recommended (Scher et al J of
    Arthro 2000, vol 15)(Joint Diseases)
  • Future technology could be polymerase chain
    reaction (PCR) which works off bacterial DNA from
    aspirates

7
Component Failure
  • Poly wear-through or fracture
  • Know the manufacturer of the implant
  • Is the poly interchangeable
  • Is the implant also loose
  • Is there any osteolysis or bone loss
  • HAVE A PLAN!

8
Knee Instability
  • History and physical
  • Symmetric laxity requiring a thicker spacer
  • Is a thicker spacer available
  • Dont get boxed out-are tibial augments indicated
  • Dont create a severe patella baja
  • PCL rupture that requires a P/S design
  • Should you switch to a P/S design if the spacer
    gets over 18 mm?

9
Knee Instability
  • You must have an array of knees available to
    cover the unexpected finding of greater
    ligamentous deficiency than was expected
  • P/S
  • P/S stabilized ( TC3 or CCK)
  • Hinges and rotating hinges
  • Full complement of augments tibia and FEMUR
  • Full complement of stems tibia and femur

10
Knee Instability
  • Flexion/Extension Gap
  • If the ligamentous instability is asymmetric then
    the imbalance must be corrected
  • This is the same technique that is utilized in a
    primary knee replacement
  • Tighten the loose gap
  • Change size
  • Move component anterior or posterior
  • Augmentation blocks on the femur

11
TKR Patients with Patellectomy
  • Patellectomy patients with total knee
    replacements who develop instability should be
    revised to a P/S design
  • Can J Surg 1996 Dec39(6)469-73 Cameron HU, Hu
    C, Vyamont D. 

12
Dislocating TKR
  • PCL retaining designs should be revised to more
    constrained knee after the ligamentous imbalance
    is diagnosed
  • P/S dislocations are more difficult
  • Most commonly loose flexion gap
  • Malrotation of the femoral component may amplify
    the ligamentous imbalance
  • May require a greater degree of constraint

13
Component Malalignment
  • Excessive internal or external rotation may lead
    to patellar tracking problems
  • Femoral component rotation is the key to a square
    flexion gap
  • References for correct rotation include
  • Transepicondylar axis
  • Posterior condyles
  • Tibial surface

14
Femoral Component Rotation and Flexion gap
Excessive IR with Lateral laxity
Correct rotation with square gap
15
Alignment deformities
  • Greater than 15 varus
  • At 10 years, patients with a fixed varus
    deformity of 15or greater had better pain
    scores, ROM, and Kaplan-Meier survival with a PS
    knee than a CR knee.
  • (Laskin et al Clin Ortho
    1996,331)

16
Patellar Tracking Problems
  • Internal rotation of the femoral component
  • Internal rotation of the tibial component
  • Functionally increases Q angle
  • Malalignment of the the limb
  • Medialized position of the femoral component
  • Lateralized position of the patellar component

17
Patellar Tracking Solutions
  • Correct rotation of components
  • Correct malalignment of limb
  • Place the new femoral component as lateral as
    possible
  • Medialize the patellar component
  • Close knee in flexion
  • Proximally realign the extensor mechanism during
    closure

18
Patellar Realignment in TKR
  • If a technical problem cannot be identified
  • Proximal realignment as described by Insall
  • Avoid distal realignment with tibial tubercle
    osteotomy
  • High complication rate in TKR
  • Can be very difficult to achieve tubercle
    fixation and union with tibial and/or cement in
    place

19
  • Insall in
  • ICL vol 25
  • 1986

20
Patellar Clunk
  • Unique to P/S knees
  • The patella may be caught in the housing for the
    post in the femoral component
  • May be a design flaw of the implant
  • May be secondary to fibrosis of the fat pad at
    the tip of the patella with subsequent catching
    of it in the housing of the post
  • Surgical removal of the tissue is indicated
  • Open or arthroscopic

21
Patellar Clunk
  • Extensor Mechanism Problems in Total Knee
    Arthroplasty
  • Dennis ICL, 1997
  • Patellar Clunk Syndrome
  • Hozack et al Clin Orthop 1989241

22
Stiffness or Limited ROM
  • Etiology
  • Technical malposition
  • Oversizing of components
  • Ligamentous imbalance
  • Too much poly
  • Tight PCL
  • Delayed physical therapy
  • Medical complications
  • miscommunication

23
Stiffness or Limited ROM
  • If a mechanical cause can be identified then
    surgery to correct the problem is frequently
    successful
  • If delayed therapy is the presumptive diagnosis,
    then open lysis of adhesions should only be
    recommended after a full and aggressive trial of
    physical therapy
  • Results in this setting are less predictable

24
Revision for only PAIN
  • R/O all infectious and mechanical causes
  • R/O RSD
  • Revision for only pain is usually unsuccessful
    and there are no clear indications
  • Jacobs, Hungerford et al Clin Orthop 1988226

25
Pre-operative Planning
  • Essential
  • Necessary equipment
  • Instruments
  • Implants
  • Grafts
  • Incision assessment
  • Be aware of the components that are in place

26
Classification of Tibial Bone Loss in TKR
  • Anderson Orthopedic Research Institute

27
Type 1 Bone Loss
  • Healthy bone
  • Normal joint line
  • Rim intact
  • Minor bone defect
  • Defect can be filled with cement or small amount
    of morsellized bone graft

28
Type 2 Bone Loss
  • Metaphyseal damage
  • A is one condyle
  • B is both condyles
  • Requires reconstruction to restore joint line
  • Augment
  • Bone
  • Longer stem

One condyle or both condyles
29
Type 3 Bone Loss
  • Major metaphyseal bone loss
  • May involve ligament
  • Major reconstruction
  • Large allograft (structural)
  • Major augments
  • Tumor custom implant
  • More constrained implants

30
Classification of Femoral Bone Loss in TKR
  • Anderson Orthopedic Research Institute

31
Skin Incisions in TKR
  • In general keep the incision as close the midline
    as possible and avoid median incisions as the
    oxygenation to the lateral flap has been shown to
    be decreased
  • If there are parallel incisions use the lateral
    incision
  • Ayers JBJS 199779A

32
Exposure in Revision TKR
  • Respect old incisions
  • Try and maintain 6-7 cm between incisions
  • Consults plastics when in doubt
  • Anticipate possible flap coverage
  • Tissue expanders are occasionally utilized
  • Keep skin flaps as thick as possible

33
Extensile Exposure in Revision TKR
  • Extend incision and quad tendon split
  • Perform extensive lateral release first
  • Increases exposure
  • Usually necessary for patellar tracking
  • Quad snip
  • Limited improvement but may maintain patellar
    tendon
  • No impact on rehab

34
Turndown vs Quad Snip
35
Quad Snip
  • Insall modified the snip to a 45
  • Protect SGA
  • Easier conversion to turndown
  • May be needed for
  • V-Y advancement

36
Exposure in Revision TKR
  • Quad snip
  • Some isokinetic weakness Garvin, Scuderi and
    Insall Clin Orthop 321131
  • No difference in clinical results Barrack et al
    Instructional Course Lecture
  • Quad turndown
  • Major exposure improvement
  • Delayed rehab
  • Significant complications
  • Flap necrosis
  • Extensor lag

37
Exposure in Revision TKR
  • Tibial tubercle osteotomy
  • Major exposure improvement
  • Delayed rehab
  • Significant complications
  • Non union
  • Patellar tendon rupture
  • Tibial fracture
  • Skin loss

38
Tibial Tubercle osteotomy
Total Knee Arthroplasty Krackow 1990
39
Tibial Tubercle osteotomy
Total Knee Arthroplasty Krackow 1990
40
Exposure in Revision TKR
  • The choice between a tibial tubercle osteotomy
    and a quad turndown is a difficult one to make.
    The presence of a large stem or compromised bone
    bed on the tibia would lean one more to the quad
    turndown. Otherwise the choice is up the the
    surgeon as each achieved dramatic exposure
    improvement at the expense of potential
    complications.

41
Revision TKR Principles
  • Maintain the the joint line
  • Reconstruct the distal femur
  • Augmentation blocks
  • Cement
  • Bone
  • Failure to do so will lead to premature loosening
    and patellar tracking problems

42
Reconstructing Defects
  • Metal is biomechanically better than cement or
    cement and screws
  • Brooks, Walker Scott et al. Clin Orthop
    1984,184302

43
Revision TKR Technique
  • Tibial blocks create better cement stresses than
    tibial wedges
  • Use a block if you are at the upper limit the
    poly thickness
  • Use some level of P/S knee if the PCL is absent
  • Always have a more constrained design available
    as a bail-out for the imponderables

44
Revision TKR Technique
  • Cement works extremely well in rev TKR when it is
    contained
  • Morsalized bone graft seems to work well when
    contained and there is a structural rim
  • Augments are indicated for uncontained defects
  • The role of structural bone graft is promising
    but long term studies are needed

45
Failed Guepar hinge
46
Cement reconstruction at 10 years
47
Revision TKR Principles
  • Stems frequently required to avoid supracondylar
    fracture
  • This is particularly true for P/S designs
  • It is also true when distal and posterior
    augments are used

48
Supracondylar Fracture
  • Failure to use a stem on this distally and
    posteriorly augmented femoral component caused a
    supracondylar fracture

49
BD Post stemmed revision
50
Revision TKR Technique
  • Address the tibia first
  • It allows the predictable creation of a stable
    reference point
  • It creates a stable reference platform from which
    the flexion and extension gaps can be assessed
  • It creates a stable reference for trial reduction

51
Revision TKR Principles
  • The next goal is to create symmetric flexion and
    extension gaps
  • This can be extremely difficult
  • Component rotation
  • Bone loss
  • Ligamentous instability or deficiency
  • Repeated trial reductions are essential and more
    important than jigs

52
Symmetric laxity in flexion and extension
  • Can usually be solved by adding a thicker poly
    which tightens both gaps symmetricly
  • Plan ahead as you may not have enough poly and
    may need an augmentation block
  • This can lead to a patella baja
  • Occasionally this may require a bigger femoral
    component with a distal and posterior
    augmentation block

53
Symmetric vs Loose in Extension
Distal augment
54
Loose in Extension
  • The solution is to tighten the extension gap and
    lower the joint line by adding a distal
    augmentation block

55
Loose in Extension
  • Adding a thicker poly is not the answer as the
    knee will jam in flexion as the flexion gap will
    become too tight

56
Loose in Flexion
  • Ideally you tighten the flexion gap
  • Adding posterior augmentation block
  • Shifting the femoral component in a posterior
    direction another option
  • Go up a size to increase the AP dimension of the
    implant
  • Increasing the extension gap by removing distal
    femur is not desirable as it moves the joint line
    proximally and worsens patella baja

57
Trials are Critical
58
Tighten the Extension Gap
59
FIXATION
  • The most consistent results have been achieved
    with all components cemented
  • This tendency is more dramatic in the tibia and
    the patella
  • Recently it has been suggested that cement may
    act as a gasket to help minimize the effective
    joint space and limit osteolysis

60
CEMENTLESS FIXATION
  • Increased failures
  • Femur tibia
  • Duffy, Berry, Rand AAHKS Nov 1997
  • Increased osteolysis
  • 16 overall
  • 11 femur
  • Cadambi et al J Arthro 1994,vol 9

61
  •   There have been 10 revisions of the femoral and
    tibial component in the uncemented group, all for
    aseptic loosening or severe osteolysis.  There
    were two revisions in the cemented group for
    aseptic loosening or severe osteolysis.  Survival
    to revision (excluding patella revision) for
    aseptic loosening at 10 years was estimated as
    87 in the uncemented group compared to 96 in
    the cemented group (P0.05).  Ten unrevised
    tibial components and 2 femoral components were
    radiographically loose in the uncemented group
    while 1 tibial component and no femoral
    components were radiographically loose in the
    cemented group.  For the tibial and femoral
    components, survival to revision for aseptic
    failure or radiographic loosening was estimated
    at 72 in the uncemented group and at 94 in the
    cement group at 10 years (P0.0008).
  • Conclusions  This study shows a significantly
    higher femoral and tibial component revision rate
    and mechanical failure rate for aseptic loosening
    and osteolysis in the uncemented compared to
    cemented TKA of the PFC design at 10 years. .
    Duffy, et al AAHKS 1997

62
Femoral Osteolysis
CM 2 yr post-op
CM 1 yr post-op
CM pre-op
63
Femoral Osteolysis
morsellized graft
64
Femoral Osteolysis
65
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66
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67
Femoral Osteolysis
68
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69
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70
Femoral Osteolysis
71
Femoral Osteolysis
72
Tibial Lysis
  • GR at 4 years post-
  • op
  • GR is symptomatic with tibial pain on weight
    bearing

73
Revision for tibial lysis
74
Results of Revision TKR
  • Large bulk allograft
  • 87 good and excellent results in 30 cases at 50
    months with no revisions
  • Engh et al JBJS July 1997
  • 77 successful results in 28 cases at 50 months
  • Ghazavi, Gross et al JBJS Jan 1997

75
Massive Allograft
Engh et al JBJS 1997
76
Massive Allograft
Engh et al JBJS 1997
77
Results Revision TKR
  • 75 good and excellent results in 40 cases at 41
    months with a complication rate of 30
  • Elia and Lotke Clin Orthop 1991271
  • 58 good and excellent results in 27 cases at 9.8
    yrs with 25 reop rate
  • Mow and Wiedel Jour Arthro 199813

78
Results Revision TKR
  • 69 good and excellent results in 39 cases at 45
    months with TC III
  • Rosenberg et al Clin Orthop 1991273
  • 83 good and excellent results when the cause of
    failure was identified. 0 good and excellent
    when PAIN was the only indication for surgery
  • Jacobs, Hungerford et al Clin Orthop 22628

79
Summary
  • KEYS
  • Accurate diagnosis of the failure of TKR
  • Careful preoperative planning
  • Bone loss
  • Complete array of revision components
  • Respect the joint line
  • Achieve a symmetric flexion extension gap

80
Summary
  • Even with significant mechanical problems 60
    -75 good and excellent results can be achieved
  • Avoid revising knees for pain in which the
    components and ligamentous balance appear correct

81
Summary
  • Thoughtful
  • Well prepared
  • Focused
  • You will not be hit by the unexpected
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