INSTABILITA` POST-CHIRURGICA diagnostica per immagini

INSTABILITA’ POST-CHIRURGICA
diagnostica per immagini
Guido Trasimeni
Le rotture dell’anulus radiali, trasversali e
concentriche indicano una ridotta rigidità
del disco intervertebrale ed una aumentata
mobilità dell’unità discosomatica.
Intervertebral disk appearance correlated with
stiffness of lumbar spinal motion segments
V M Haughton et al. AJNR 1999
STIFFNESS AVERAGED
7.0 Nm/degree for normal group
3.1 Nm/degree for disks with advanced degeneration
1.9 Nm/degree for disks with concentric or trasverse tears
1.7 Nm/degree for disks with radial tears
T4
T5
T6
2005
2009
2012
190 patients
Microsurgically treated for a virgin single level
lumbar disc herniation
Mean follow-up period 3 yr
22%
instability!
had sign and symptoms
Twice discectomy for de L5-S1, in 3 months.
Good outcome for 6 yr……radiculopaty L5 distribution.
estensione
flessione
Twice discectomy for de L5-S1, in 3 months.
Good outcome for 6 yr……radiculopaty L5 distribution.
MR: synovial cyst L4-5 left, discopathy L3-4, L4-5.
6 aa prima, età 62 aa
….a disc prosthesis may cause less adjacent level degeneration (ALD)
1 , 2 Fusion might accelerate ALD beyond the natural course
than
fusion
ALD was observed at similar frequencies at the 2-year follow-up.
3,4
of disc degeneration
However,
the surgery group had increased facet arthropathy at the
implant level.
3 yr post disk prosthesis……….lbp and left radiculopaty
estensione
Courtesy of Enzo Pacciani
flessione
18 yrs post arthrectomy L5-S1 left………radiculopaty L4 right
Flessione
Estensione
18 yrs post arthrectomy L5-S1 left………radiculopaty L4 right
L4-5
S1
L5
S1
11 aa prima intervento di laminectomia L5-S1 per stenosi.
Da 2 mesi lsc dx con distribuzione L5.
estensione
flessione
11 aa prima intervento di laminectomia L5-S1
per stenosi.
Da 2 mesi lsc dx con distribuzione L5.
DX
SN
Evidence of disk herniation after load in a p. that had had previous surgery twice for
disk herniation and acute LBP
Neutral
Loading
Increased disk herniation after loading in patient previous operated
with laminectomy
Conclusioni
• Nel sospetto clinico di instabilità post
chirurgica eseguiamo studio radiologico
anche con radiografie in flesso estensione.
• Nei casi di discordanza clinicoradiologica, ulteriori informazioni
possono essere ottenute con esame RM
con carico (AXL-MR).
Grazie
Modic endplate changes
• Type 1 changes are likely to be inflammatory in origin and seem to
bestrongly associated with active low back symptoms and segmental
instability, thus reflecting a state of active degeneration and
biomechanical instability of the lumbar spine.
Accordingly, these changes appear to predict an
excellent outcome following lumbar fusion.
AJNR 29 May 2008