Crook Disc Prognosis

(Or what’s worth observing) By Dr David McGrath

Pre 1997 State of Affairs

Biological Variables: Duration of Pain, Past Hx of Pain, Leg Pain, BMI, (Disability)

Psychosocial Variables: Education, MMPI, Sickness Impact score, Depression, Coping level, Distress, Fear

Work Variables: Job Satisfaction, Work Capacity.

Fear- Avoidance Model

Intolerance of activity may not be a biological factor but instead have a substantial behavioural basis

Activity intolerance can be explained by a combination of pain severity, depression and illness behaviour

Fear avoidance can lead to chronicity Basis for cognitive /behavioural Rx

Epidemiological Shortcomings

The results of a survey will be a function of the questions asked

More reliable studies include a large number of variables then submit them to multiple regression analysis

Longitudinal studies are best

Medline Searches 1999-2005

LBP LBP + Natural History IDD + Natural History LBP + Disc Prolapse LBP + Prognostic

Ascending Chronological Order

No judgement about quality of study, only if they seem to address prognostic indicators

Individual studies and literature reviews

1999 Far-Lateral Disc Herniations

N=16 Radicular Pain (concordant with root) 3 year study 71 % Full recovery with no surgery Ref (1)

1999 VEP # Hypothesis

Common Cause of BP is vertebral end plate fracture

“ natural history” of BP consistent with hypothesis

Ref 2

2000 Relation between Intensity, Disability, Recurrence of LBP

N=94 Disability +ve correlates with pain intensity Episodic nature of painful periods -ve

correlates with functionality at work and home

“Not a static phenomenon” Ref (3)

2000 Exercise Rx and Outcome post Discectomy

N=20 Exercise vs normal activities 4 week exercise program Improvements in pain, spinal ROM, disability

score over non exercise group Maintained at 1 year Ref(4)

2000 N/H Asymptomatic Disc MRI

N=46 5 year follow up No change to herniations or neural compression “Disc degeneration” progressed in N=17 Minor episodes of LBP in N=19 5 of 19 obtained Sick Leave 5 S/L best predicted by job characteristics and job

satisfaction and NOT MRI Ref(5)

2000 Herniated Discs

N/H of nucleus pulposus herniations complex with variables such as inflammation, compression and pain altering prognosis

Relationship between Imaging and LBP or radiculopathy not clear

“Value” of MRI may be monitoring changes in longitudinal studies

Ref (6)

2000 Prospective LBP Study

N=1455 Questionairre blind survey to adults 1/3 lifetime NO LBP 4% year new incidence rate 40% intermittent LBP Ref (7)

2000 Socioeconomic aspects MRI

MRI facilitates “medicalization” of LBP Urging radiologists to avoid unnecessary

labelling possibly leading to inappropriate treatment

Ref (8)

2000 Surgery Disc Prolapse

Cochrane Review up to 31/12/99 N=27 trials Surgical discectomy provides faster relief from acute

attack than conservative management but +ve or –ve effects on lifetime natural history is unclear

Chemonucleolysis better than placebo but worse than surgery

All surgery similar results Ref (9)

2002 N/H Sequestrated Disc Herniation

N=49 Signal Intensity on T2 of herniation compared

to nucleus pulposus is indicator of potential for herniation reduction with time

Ratio of intensities >1.2 predictive Ref(10)

2002 N/H Disc Herniation with Radiculopathy

“Majority” of patients suffering radiculopathy (Herniated NP) resolve spontaneously without surgery or chemonucleolysis

Ref(11)

2002 LBP General Population

Population of 17,000 2 year follow up of LBP patients No predictive factors for recovery 2% per year new LBP event LBP often becomes chronic even when sick

leave is rare Ref(12)

2002 N/H & Risk Factors Musculoskeletal Conditions US Army

N=15268 LBP conditions greatest risk of disability Male Risk Factors: low pay, diagnosis, shorter

length service, older, occ category, lower job satisfaction, smoking, work stress, physical demands.

Female Risk: Lower Educational level Ref(13)

2003 N/H Spodylolysis & Spondylolithesis

N=30 from a population of 500 Inception ages 6-30 45 year follow up Unilateral defects NO slippage Progression of slip slowed with decades No association slip and pain Pain and disability scores same as age cohort Ref(14)

2003 GP perceptions of LBP

Straightforward condition or complicated? Frustration with those that fail to recover Biomechanistic approach and good N/H

works well for most Psychological and social dimensions? Ref(15)

2003 N/H of Aging Spine

Multiple structural changes “unrelenting changes leading to scoliosis,

destabilisation, and rupture of equilibrium” Ref(16)

2003 Risk factors for progression of disc degeneration

N=796 Mean age of cohort 54 Mean BMI 25 Anterior osteophytes (AO) and disc narrowing (DSN) AO Progression correlates with age, radiographic OA

of hip. DSN progression correlates age, BP, radiographic

AO hip and knee Nil significance for smoking, physical activity, other Ref(17)

2003 Acute LBP Prognosis

Literature review Most people recover rapidly Recurrence common Ref(25)

2003 LBP Prognosis post MVA

N=4473 Change in legal entitlement with no common

law claims Claim closure faster Higher pain, slower claim closure Ref(26)

2003 Prognosis Subacute LBP

N=164 Working group Duration pain 4-12 weeks Predictors, age and pain intensity Type of work, not work satisfaction predictive Ref(30)

2004 Management Chronic LBP

Opinion Monotherapies. Either don’t work or limited efficacy Multidisciplinary based on intensive exercises.

Improves physical function and has modest effects on pain.

Reductionism. Pathoanatomical diagnosis. Treatments are emerging for Z, disc,S/I joints.

Ref(18)

2004 N/H and prognostic indicators of sciatica

N=622 Workers electricity/gas Follow up 2 years Factors predictive of persistence or

recurrence were: driving at least 2 hours per day, carrying heavy loads at work, a high level of psychosomatic problems, and pain preceeding onset of study.

Ref (19)

2004 Dutch Army “minimal intervention” LBP

“minimal sports medicine approach” 2 short training sessions per week Study in progress Ref(27)

2004 Prognostic Factors Recurrent BP

Prospective cohort, factory Holland Prognostic factors, high disability and to a

lesser degree job satisfaction, low decision authority, low social support.

Ref(28)

2004 Scaffolders LBP

N=288 3 year Questionnaire study 20% pain every year. 26% nil pain every year. High rate of BP incidence, recurrence and recovery High association of cumulative recurrence with

manual handling, high job demands, low job control Weak association with BMI, general health Ref(20)

2004 Quality of Life Prognostic Indicator of Acute LBP

N=113 5% developed chronic LBP Delayed recovery with compensation status,

initial disability, lower SF-36 (quality of life) Lower SF-36 with psychiatric disorders,

unemployed, comorbidity, job dissatisfaction, foreign origin.

Ref(21)

2004 LBP Diagnosis, Rx, Prognosis

Rx’s mostly pain modulating, not cure N/H favourable A worry is long term disabled Fear avoidance behaviour part of disabling

pathway Removing fear and uncertainty. The back is

“robust even if it hurts”. Promising approach. Ref(22)

2004 Outcomes with peri-radicular infiltration, disc herniation

N=55 Radicular pain Mean change VAS 2 3 month follow up N/H or treatment effect? Ref(23)

2004 Fear Avoidance Validation LBP

N=388 Assessment 6 months post treatment Fear avoidance score predictive of chronicity Ref(31)

2004 Ergonomic Interventions LBP

N=1631 “ergonomic Interventions are Successful” Ref(32)

2004 LBP Outcomes Longitudinal Study

N=? 1 year follow up 75 % continuing symptoms Baseline pain and general health predicitive

of continuing BP Work satisfaction and negative event

predictive of pain and disability Ref(24)

2004 LBP in young NZers

N=969 Birth cohort age26 LB data questionnaire. BP previous year. 54% LBP previous one year with 3-4 times a

episodes year N=448 working. No difference between professional,

clerical, technical, trade or production. N=56 required S/L

N=13 unable to care for themselves Ref (25)

2004 Prolotherapy

Systematic Review 4 trials high quality Conclusions confounded by clinical

heterogeneity and co-interventions No evidence that prolotherapy alone more

effective than control injections. Ref(26)

2004 RTW LBP Prognosis

Literature Review Prognostic Factors: P/H of LBP, low level job

satisfaction, poor general health Other factors such as wage, compo,

depression, physical factors, work postures less significant

Ref(35)

2004 Prognosis Lumber Discectomy

N=48 Poor outcome predicted by reduced SLR,

depression Ref(36)

2004 Prognostic Value of Functional Capacity Evaluation

N=226 Validity of Functional Capacity assessments

“suspect” Ref(33)

2004 Back Schools LBP

Literature search Content of schools has changed Moderate evidence schools in occupational

setting reduce pain, improve function and RTW status cf to Other treatments.

Ref(27)

2004 McKenzie

Systematic Review 6 trials Better results than Other for LBP with short

term pain/disability No trials for McKenzie vs placebo Insufficient data for neck pain Ref(28)

2005 Questionnaires. What do they assess

Main focus on activity limitations Considerable variation Only a few could be considered acceptably

validated using WHO criteria Ref(29)

2005 Behavioural treatment for chronic LBP

Cochrane database Better than waiting list in short term No significant difference between

behavioural and exercise No conclusions or recommendations can be

made from this data Ref(30)

2005 Multidisciplinary Rehab Prognosis

N=? Predictive of poor outcome was number of

pre admission health care visits Ref(37)

2005 Acupuncture LBP

Cochrane data base Data does not allow firm conclusions for

acute LBP For chronic LBP better than nil Rx

immediately after Rx and short term No more effective than other Rx Data suggests useful adjunct to other Rx Ref(31)

Conclusions 2005

Biological variables continue to have predictive power. In particular Intensity of pain and previous episodes.

Probably lack of diagnostic precision hampers further progress. Imaging findings have poor predictive capacity as they distinguish structural pathology NOT painful pathology. Precision needle techniques are often used as therapeutic interventions.

Spinal physiology needs improving.

Conclusions 2005 (contd)

BP tends to be a recurring problem. We do not know why. The structural limits of a component are probably exceeded during flare ups. Adaptive changes such as tissue remodelling may be overwhelmed in the short term or longer.

Ability is a multi-dimensional concept of interaction. Any of these variables can have a feedback influence on a vulnerable structure through spinal and neural dynamics.

Conclusions 2005 (contd)

In a work environment, work variables will be found which influence pain disability.

In a social milieu, psychosocial variables will be identified.

Conclusions 2005 (contd)

Evidence Suggests

1. Don’t over diagnose

2. Don’t over treat

3. Don’t over prognosticate

4. Resume normal everyday activities ASAP

5. Explain/Reassure. Expect flare ups.

Conclusions 2005 (contd)

Interactive Model might be useful

1. What painful structure/s

2. What underlying spinal dynamics

3. What environment

4. What adaptive skills