3. Validation of a “Minimum Acceptable Outcomes” Model for Outcomes Assessment in Spinal Surgery

  • Published on
    29-Nov-2016

  • View
    212

  • Download
    0

Embed Size (px)

Transcript

  • even though minimum outcomes were not achieved).

    CONCLUSIONS: The minimum acceptable outcome method appears

    to be a well validated means of defining success for most patients hav-

    2S Proceedings of the NASS 22nd Annual Meeting / The Spine Journal 7 (2007) 1S163SFigure 1. DEXA Scan image and Cobbs measurment

    CONCLUSIONS: Our study indicates that the prevalence of lumbar sco-

    liosis in adults is 8.85%. Increasing age was associated with increasing

    likelihood of scoliosis while non-white race was associated with reduced

    likelihood of scoliosis.

    FDA DEVICE/DRUG STATUS: This abstract does not discuss or include

    any applicable devices or drugs.

    doi: 10.1016/j.spinee.2007.07.006

    3. Validation of a Minimum Acceptable Outcomes Model for

    Outcomes Assessment in Spinal Surgery

    Eugene Carragee, MD1, Ivan Cheng, MD2, Mark Wang, MD1; 1Stanford

    University, Stanford, CA, USA; 2Stanford School of Medicine, Stanford,

    CA, USA

    BACKGROUND CONTEXT: Defining clinical success after spinal

    surgery has proven problematical. Arbitrary benchmarks such as 2 point

    improvements on the VAS scale or 10 point improvements by the Oswestry

    Disability Index, are frequently within the spontaneous variation of the

    condition and often well below patients expectations of clinical improve-

    ment. Previous studies have described a method to determine the pre-

    operatively minimal acceptable outcomes as described by patients

    having spinal surgery.

    PURPOSE: To establish the validity of patient-determined minimum ac-

    ceptable outcomes as a criteria of surgical success in patients undergoing

    spinal surgery.

    STUDY DESIGN/SETTING: Validation study of the minimum accept-

    able outcomes after spinal surgery.

    PATIENT SAMPLE: Consecutive cohort of patients having decompres-

    sion and / or fusion surgery of the lumbar spine.

    OUTCOME MEASURES: Outcomes were assessed using the VAS for

    the severity of back and leg pain, ODI, pain medication usage, and work

    loss by standard questionnaire. These were compared to post-operative

    global satisfaction. Concordance of satisfaction and achievement ofing spinal surgery. Global satisfaction in patients not achieving pre-

    operative minimum goals is highly correlated with psychosocial issues

    and may indicate that satisfaction in these patients is a related to factors

    other than functional improvement, return to work or discontinuing pain

    medications.

    FDA DEVICE/DRUG STATUS: This abstract does not discuss or include

    any applicable devices or drugs.

    doi: 10.1016/j.spinee.2007.07.007

    4. Epidural Application of Particulate Wear Debris: A

    Comprehensive Analysis of Ten Different Implant Materials Using

    an In-Vivo Animal Model

    Bryan W. Cunningham, MSc1, Candace M. Zorn, BS1, Nianbin Hu, MD1,

    Nadim Hallab, PhD2, Paul C. McAfee, MD3; 1St. Joseph Medical Center,

    Towson, MD, USA; 2Rush University Medical Center, Chicago, IL, USA;3St. Joseph Hospital, Towson, MD, USA

    BACKGROUND CONTEXT: N/A

    PURPOSE: The effect of particulate wear debris from the bearing sur-

    faces of motion preserving spinal implants remains a clinical concern. Us-

    ing an in-vivo rabbit model, the current study serves to quantify the neural

    and systemic tissue histopathological response, following epidural applica-

    tion of ten different types of particulate wear debris used in motion pre-

    serving spinal implants.

    METHODS: One Hundred New Zealand White rabbits were equally ran-

    domized into ten groups (n510 group) based on treatment material: 1)

    Sham (control), 2) Stainless Steel 316LVM, 3) Titanium Alloy Ti-6AL-

    4V, 4) Cobalt Chrome Alloy, 5) Ultrahigh molecular weight polyethylene

    (UHMWPE), 6) Polycarbonate Urethane (PCU), 7) Polyetheretherketone

    (PEEK), 8) Polyvinyl Alcohol (PVA), 9) Polyester and 10) Ceramic. The

    surgical procedure consisted a midline posterior approach, followed by re-

    section of the L6 spinous process and ligamentum flavum at L5-L6 per-

    mitting interlaminar exposure of the dural sac. 4mg (size range 0.350

    diameter; dosage 300 to 600 million particles) of the appropriate treatment

    material was then implanted in dry, sterile format. Five animals fromminimum acceptable outcomes was analyzed as a function of baseline

    demographic, surgical and psychometric factors.

    METHODS: Minimum acceptable outcome (pre-operatively-determined)

    and satisfaction (at two years post-operatively) were prospectively studied

    in 298 consecutive having lumbar spine surgery. Baseline pre-operative

    values were assessed using the visual analog scale (VAS) for the severity

    of back and leg pain, the Oswestry Disability Index (ODI), and recorded

    a history of pain medication usage, pre-operative symptom duration, work

    status and amount of pre-operative work loss on a standard questionnaire.

    These subjects were then given standardized forms to complete indicating

    minimum-acceptable outcome signifying worst of outcome in each dimen-

    sion for which they would undergo surgery. Subjects were then followed

    for two years and their outcomes and satisfaction compared to the mini-

    mum acceptable outcomes previously determined.

    RESULTS: There was a wide variation in what individual patient consid-

    ered a minimum acceptable outcome for spinal surgery. However, valid-

    ity appears to be high as subjects achieving their own minimum acceptable

    outcome very commonly reported post-operative satisfaction (Positive

    Predictive Value586%, CI 8290%). Conversely, not achieving the mini-

    mum acceptable outcome was associated with satisfaction 36% of the cases

    (Negative predictive value564%, CI 5672%). Satisfaction despite failure

    to achieve minimum acceptable outcomes was more common in certain

    subgroups: baseline factors of psychological distress, workers compensa-

    tion claims, litigation, and other chronic pain problems at baseline predicted

    a dissociation on minimum acceptable outcomes stated at baseline and sat-

    isfaction of follow-up (i.e. patients may indicate satisfaction with treatment

    3. Validation of a Minimum Acceptable Outcomes Model for Outcomes Assessment in Spinal Surgery4. Epidural Application of Particulate Wear Debris: A Comprehensive Analysis of Ten Different Implant Materials Using an In-Vivo Animal Model

Recommended

View more >