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Title: science


1
Chondral lesions in adults
  • Abdelsamie Halawa MD
  • Banha faculty of medicine
  • 2015

2
Introduction
  • Articular cartilage covers the articulating
    surfaces within joints
  • functions include load transmission,
    lubrication, joint congruity
  • Cartilage injuries have limited spontaneous
    healing
  • may progress to arthritis

3
Anatomy
4
Presentation
  • Symptoms
  • localized pain, effusion, mechanical symptoms
  • Physical exam
  • joint effusion, focal tenderness

5
Imaging
  • Radiographs
  • used to rule out arthritis, bony defects, and
    check alignment
  • weight bearing 45 deg PA most sensitive for early
    joint space narrowing 
  • merchant view for patello-femoral joint 
  • double limb standing long films to check
    alignment 
  • MRI
  • most sensitive for evaluating focal defects
  • Fat-suppressed T2, proton density, T2 fast
    spin-echo (FSE) offer improved sensitivity and
    specificity over standard sequences
  • dGEMRIC (delayed gadolinium-enhanced MRI for
    cartilage) and T2-mapping are evolving techniques
    to evaluate cartilage defects and repair 
  • CT scan
  • better evaluation of bone loss
  • used to measure TT-TG when evaluating the
    patello-femoral joint

6
TT-TG measurement
(1) line tangent to the posterior epicondyle
(red), (2) perpendicular line through deepest
point of the trochlea (blue), (3) line parallel
to the trochlea line through the most anterior
portion of the tibial tuberosity (green) TT-TG
measurement is distance btwn blue green lines. 
ABNORMAL if gt 20 mm ? shows valgus component of
extensor mechanism of knee associated with
patellar instability trochlear dysplasia 
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8
dGEMRIC (delayed gadolinium-enhanced MRI for
cartilage)  
9
Outerbridge Arthroscopic Grading System
  • Grade O? Normal cartilageGrade I? Softening
    and swellingGrade II? Partial thickness defect,
    fissures lt 1.5cm diameter
  • Grade III? Fissures down to subchondral bone,
    diameter gt 1.5cm
  • Grade IV? Exposed subchondral bone

10
ICRS (International Cartilage Repair Society)
Grading System
  • Grade 0 ? Normal cartilageGrade 1 ? Nearly
    normal (superficial lesions)Grade 2 ? Abnormal
    (lesions extend lt 50 of cartilage depth)
  • Grade 3 ? Severely abnormal (gt50 of
    cartilage depth)
  • Grade 4 ? Severely abnormal (through the
    subchondral bone)

11
Treatment
  • Non-operative
  • rest, NSAIDs, bracing
  • indications
  • first line of treatment when symptoms are mild
  • corticosteroid injections, hyaluronic acid,
    glucosamine
  • indications
  • controversial 
  • may provide symptomatic relief but healing of
    defect in unlikely

12
  • Operative
  • debridement/chondroplasty vs. reconstruction
    techniques 
  • indications
  • failure of non-operative management 
  • technique
  • treatment is individualized, there is no one best
    technique for all defects
  • decision-making algorithm is based on several
    factors
  • patient factors
  • age
  • skeletal maturity
  • low vs. high demand activities
  • ability to tolerate extended rehabilitation
  • defect factors
  • size of defect
  • location
  • contained vs. uncontained
  • presence or absence of subchondral bone
    involvement

13
Surgical Techniques
  • Debridement / Chondroplasty
  • overview
  • goal is to debride loose flaps of cartilage
  • may relieve mechanical symptoms from loose
    chondral fragments
  • short-term benefit in 50-70 of patients
  • benefits 
  • include simple arthroscopic procedure, faster
    rehabilitation
  • limitations
  • problem is exposed subchondral bone or layers of
    injured cartilage
  • unknown natural history of progression after
    treatment

14
  • Fixation of Unstable Fragments
  • overview
  • need osteochondral fragment with adequate
    subchondral bone
  • technique
  • debride underlying nonviable tissue
  • consider drilling subchondral bone or adding
    local bone graft
  • fix with absorbable or nonabsorbable screws or
    devices
  • benefits
  • best results for unstable osteochondritis
    dissecans (OCD) fragments in patients with open
    physis
  • limitations
  • lower healing rates in skeletally mature patients
  • nonabsorbable fixation (headless screws) should
    be removed at 3-6 months 

15
  • The optimal treatment for chondral defects is
    debatable.
  • The current options are
  • distraction,
  • debridement,
  • Abrasion,
  • microfracture,
  • antegrade or retrograde drilling,
  • Mosaicplasty
  • osteochondral autograft transfer system (OATS),
  • autologous chondrocyte implantation (ACI),
  • matrix-induced autologous chondrocyte
    implantation (MACI),
  • autologous matrix-induced chondrogenesis (AMIC),
  • allologous stem cell transplantation,
  • allograft bone/cartilage transplantation .

16
  • Marrow Stimulation Techniques 
  • overview
  • goal is to allow access of marrow elements into
    defect to stimulate the formation of reparative
    tissue
  • includes microfracture, abrasion arthroplasty,
    osteochondral drilling
  • Microfracture technique 
  • defect is prepared with stable vertical walls and
    the calcified cartilage layer is removed
  • awls are used to make punctate perforations
    through the subchondral bone 
  • protected weight bearing and continuous passive
    motion (CPM) are used while mesenchymal stem
    cells mature into mainly fibrocartilage  
  • benefits
  • include cost-effectiveness, single-stage,
    arthroscopic
  • best results for acute, contained cartilage
    lesions less than 2x2cm
  • limitations
  • poor results for larger defects
  • does not address bone defects

17
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18
Abrasion arthroplasty,
  • The superficial dead sclerotic layer is abraded
    by the burr in a universal mannar till the tide
    mark
  • protected weight bearing and continuous passive
    motion (CPM) are used while mesenchymal stem
    cells mature into mainly fibrocartilage  
  • benefits
  • include cost-effectiveness, single-stage,
    arthroscopic
  • best results for chronic, uni-compartmental OA,
    and when associated with alignment procedures as
    HTO
  • limitations
  • poor results for many compartmental OA
  • Technically demanding , as abrasion beyond the
    tide mark will lead to pain

19
Abrasion arthroplasty
The abrasion arthrplasty is a combined procedure
many actions inside the knee 1- Partial
synovectomy 2- Partial menisectomy 3- Loose body
removal and osteophyts of mechanical block 4-
Abrasion
20
Osteochondral drilling
The surgery was developed in the late 1980s and
early 1990s by Dr. Richard Steadman of the
Steadman-Hawkins clinic in Vail, Colorado
21
  • Osteochondral autograft / Mosaicplasty
  • overview
  • goal is to replace a cartilage defect in a high
    weight bearing area with normal autologous
    cartilage and bone plug(s) from a lower weight
    bearing area
  • chondrocytes remain viable, bone graft is
    incorporated into subchondral bone and overlying
    cartilage layer heals. 
  • technique
  • a recipient socket is drilled at the site of the
    defect
  • a single or multiple small cylinders of normal
    articular cartilage with underlying bone are
    cored out from lesser weight bearing areas
    (periphery of trochlea or notch)
  • plugs are then press-fit into the defect
  • limitations
  • size constraints and donor site morbidity limit
    usage of this technique
  • matching the size and radius of curvature of
    cartilage defect is difficult
  • fixation strength of graft initially decreases
    with initial healing response
  • weight bearing should be delayed 3 months 
  • benefits 
  • include autologous tissue, cost-effectiveness,
    single-stage, may be performed arthroscopically

22
  • Osteochondral allograft transplantation 
    System(OATS Mega OATS)
  • overview 
  • goal is to replace cartilage defect with live
    chondrocytes in mature matrix along with
    underlying bone
  • fresh, refrigerated grafts are used which retain
    chondrocyte viability
  • may be performed as a bulk graft (fixed with
    screws) or shell (dowels) grafts
  • technique
  • match the size and radius of curvature of
    articular cartilage with donor tissue
  • a recipient socket is drilled at the site of the
    defect 
  • an osteochondral dowel of the appropriate size is
    cored out of the donor 
  • the dowel is press-fit into place
  • benefits 
  • include ability to address larger defects, can
    correct significant bone loss, useful in revision
    of other techniques
  • limitations
  • limited availability and high cost of donor
    tissue
  • live allograft tissue carries potential risk of
    infection

23
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24
  • Autologous chondrocyte implantation (ACI) 
  • overview
  • cell therapy with goal of forming autologous
    "hyaline-like" cartilage
  • technique 
  • arthroscopic harvest of cartilage from a lesser
    weight bearing area
  • in the lab, chondrocytes are released from matrix
    and are expanded in culture
  • defect is prepared and chondrocytes are then
    injected under a periosteal patch sewn over the
    defect during a second surgery
  • benefits 
  • may provide better histologic tissue than marrow
    stimulation
  • long term results comparable to microfracture in
    most series
  • include regeneration of autologous tissue, can
    address larger defects
  • limitations 
  • must have full-thickness cartilage margins around
    the defect
  • open surgery
  • 2-stage procedure
  • prolonged protection necessary to allow for
    maturation

25
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26
  • Matrix-associated autologous chondrocyte
    implantation
  • overview
  • example is "MACI" 
  • cells are cultured and embedded in a matrix or
    scaffold
  • matrix is secured with fibrin glue or sutures
  • benefits
  • include ability to perform without suturing, may
    be performed arthroscopically
  • limitations
  • 2-stage procedure
  • in worldwide use/evaluation- not available in the
    USA

27
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28
Matrix-associated stem cell transplantation (MAST)
29
  • (a and b) Chondro-Guide1 matrix (Geistlich,
    Baden-Baden, Germany). This matrix contains
    collagen I and III. The matrix has two layers
    (bilayer). The superficial layer is water proof
    (a and b, top). The deep layer is porous (b,
    bottom). Different sizes are available.

30
  • Patellar cartilage unloading procedures
  • Maquet (tibia tubercle anteriorization)
  • indicated only for distal pole lesions
  • only elevate 1 cm or else risk of skin necrosis
  • contraindications
  • superior patellar arthrosis (scope before you
    perform the surgery)
  • Fulkerson alignment surgery (tibia tubercle
    anteriorization and medialization   
  • indications (controversial)
  • lateral and distal pole lesions 
  • increased Q angle
  • contraindications
  • superior medial patellar arthrosis (scope before
    you perform the surgery) 
  • skeletal immaturity

31
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