INDIRECT SPINAL DECOMPRESSION FOR SPINAL STENOSIS
Dr. A. Sivaraman
FRCS(Eng) FRCS(Ed) FRCS(Orth)
Consultant Orthopaedic Spinal Surgeon
The Royal London & St Bartholomew's Hospital
Neurogenic Intermittent Claudication - Central - Lateral/foraminal stenosis
Spondylolisthesis (<1.5) with NIC
Kissing Spine / Baastrup
Facet Syndrome
Degenerative and/or iatrogenic (post-discectomy) Disc Syndrome
Contained HNP
Adjacent level syndrome, primary or secondary
Indications
Prevents Canal Narrowing
With the X STOP in place:
Canal Area is 18% greater Canal Diameter is 9% greater Subarticular Diameter is 50% greater
Richards et al, ISSLS 2002 Intact, extension X STOP, extension
Prevents Foraminal Narrowing
With the X STOP in place:
Foraminal Area is 25% greater Foraminal Width is 41% greater
Intact, extension X STOP, extension Richards et al, ISSLS 2002
Spinal Kinematics Spinal Kinematics
Axial RotationX STOP = 1.6o
Intact = 1.7o
Lateral BendingX STOP = 8.8o
Intact = 8.2o
X STOP
Flexion/ ExtensionX STOP = 3.1o
Intact = 7.6o
Disc Pressure
• L3-4: X STOP in Extension• 63% decrease in posterior annulus
pressure• 41% decrease in nucleus pulposus
pressure• L3-4: X STOP in Neutral
• 38% decrease in posterior annulus pressure
• 20% decrease in nucleus pulposus pressure
• No significant affect on the disc pressures at the adjacent levels
p< 0.05%
Disc Pressure
At the implanted level: Contact Area (43%) Pressure (61%) Peak Pressure (58%) No significant differences
at the adjacent levels
Intact X STOP
L2-3
L3-4
L4-5
Facet Load Results
Lumbar Spinal Stenosis Clinical Outcome with X-STOPTM : a prospective cohort
Mr.A.Sivaraman Mr.S.Tucker Mr.C.Natali Mr.M.H.Noordeen Royal National orthopaedic hospital, Stanmore EJOST 2007
Methods
Prospective study June 2004 Mean Age: 61.5 (52- 94 yrs) 46 patients 26 Females, 20 Males Neurogenic claudication
Results
Operative time - 50 mins (40-70 mins) for multilevel implantations Hospital stay - 2 days (1.5 - 3 days) Blood loss- < 50 ml No neurological complication
Results Improvement in walking distance - 68%
Improvement in ODI by 12% or more - 90% (p<.0001)
Improvement in SF12 Physical score - 70% (p=.0003)
Improvement in SF12 Mental score - 80%(p=.005)
Consumption of NSAID Stopped - 55% Occasional - 35% Regular use - 10%
Patient satisfaction - 82%
Results
Leg pain
Back pain
ODI SF12 Physical score
SF12 Mental score
Pre 6.7 (0-10)
6.8 (1- 9)
42% (10-82)
11.31 (6- 15)
16.54 (6- 24)
Post 2.7 (0- 7)
2.8 (0- 5)
16.4% (0-58)
16.04 (10- 20)
22.76 (11-27)
Complications
Superficial wound infection - 2 - Settled with oral antibiotic Dysesthesia - 3 Wound haematoma - 1
Technical difficulty - 1
Third Generation Implants
WELLEX™ DYNAMIC LOAD RELATED (50N / 100N) LOAD SHARING INSTEAD OF LOAD BEARING
Patient Group
APRIL 2009 - TO DATE 42 PATIENTS 4 TWO LEVEL PROCEDURES AVERAGE SURGERY TIME - 30 MTS AVERAGE LOS- overnight