Lx 2 - Ms Taylor

acute LBP + R leg pain / derm neuro Sx

most likely clinical presentation

R L5 radiculopathy + possible disc herniation

differential diagnoses

• peroneal nerve entrapment

• S1 radiculopathy

• spinal stenosis

assessment technique + why

neurodynamic tests - slump/SLR

• cough Sx suggest neural mechanosensitiviity
• Ax mobility + sensitivity of peripheral nerves
• provocative - be careful, can be discomfort

assessment technique results

positive - reproduce radicular pain/Sx eg tingling, numb, shooting pain expect - positive - confirms radiculopathy/nerve involvement

assessment technique performance

slump test - sit edge plinth hands behind back

• slump at Tx/Lx spine
• if no pain - add neck flex, extend knee, DF ankle SLR/Lasegue's sign - supine, hold heel and gradually raise straight leg to increase hip flexion
• increase sensitivity - ankle DF + neck flex

management - education

• reduce fear, increase confidence, correct misconceptions on nerve damage
• Sx fit L5 nerve root irritation - nerves strong/recover well, not easily damaged
• pain/p+n due to nerve sensitivity not permanently harmed
• avoiding movement increases sensitivity
• movement + gentle exercises help nerve glide and reduce irritation
• gradually rebuild confidence to return to gym/swim - achievable

management - pharmocological

• shared decision making on stopping opioids, gabapentinoids etc for sciatica
• be aware of risk/harms/limited benefit NSAIDs
• if NSAIDs, consider GI, risk factors, age, clinical assessment
• lowest effective dose for shortest possible period of time
• consider neuropathic pain management - dosage based on response/tolerability

beliefs and disability evidence

Schwab+Silva 2023 - research on how beliefs about damage strongly influence disability

• align with pain principle that fear avoidance and catastrophising increases disability
• education decreases fear and enhances recovery
• addressing and correcting misconceptions essential for improving patient outcomes

education evidence

NICE GL on LBP

• education 1st line management CLBP
• emphasise reassurance, stay active, avoid fear avoidance, encourage normal activities
• self management - advice + info on nature of LBP
• explain nerve irritation does not equal nerve damage - reduces anxiety and improves adherence

management - exercise 1 justification

neural mobilisation - sciatic/L5 slider

• decrease neural sensitivity
• increase nerve mobility
• decrease leg pain
• low load, simple

L5 slider demo + dose

demo - lying supine, hold knee towards chest as far as comfy

• gently straighten knee as PF ankle
• bend knee as DF ankle
• alt tension/slack - slider dose - 2x10-15 daily

L5 slider pro/regression

regression

• decrease range
• slower tempo
• supine
• sidelying (pillow between knees) progression
• seated increases load
• increase rom knee ext
• ass ankle DF at end range

L5 slider evidence

Lin et al 2023 - SR/MA of RCTs

• neural mobilisation for Lx radiculopathy sig reduced pain and disability
• mod-strong evidence for less pain, disability, neuropathic Sx, neural mechanosensitivity, esp w/exercise rehab

management - exercise 2 justification

LL strength - marching

• reduce tripping
• support gait
• increase confidence in movement

marching demo + dose

demo - stand and hold surface

• flex hip, knee, ankle
• lower slow/smooth dose - 8-12reps 2-3 sets 1-2x daily
• slow, controlled, hold 2secs at top rest 30-45secs between sets

marching pro/regression

regression

• seated
• reduce range
• hold for balance
• split into 3 joints progression
• march w/o support
• increase hold at top
• step-overs
• march 30secs > reps
• resistance band

marching evidence

literature

• motor deficits respond well to targeted strengthening
• stronger hip/knee/ankle flexor reduces tripping in lift-off phase of gait

pathophysiological evidence for exercise

neural mobilisation

• neural sliders reduce pain and improve function in Lx Rx
• improve intraneural blood flow, reduce inflam, restore mobility
• sliders more comfortable and safer than tensioners in acute Rx LL strengthening
• L5 innervates DF muscle, increase strength reduces tripping
• early activation weak myotomes increases recovery for Rx
• activates L5 muscle in safe, low load way
• task specific to increase confidence, reduce fear avoidance, supports return to meaningful activity

goal relevance of education/exercise

gym/swim

• exercises reduce nerve sensitivity and improve leg strength - help move confidently again
• symptoms settle, gradually increase activity to get back to things you enjoy without worrying about nerve damage

Lx radiculopathy

compression of nerve root - inner NP pushes into outer AF (innervated) chemical inflam - exposure of nuclear material releases cytokines

• root chemoradiculitis/chemical inflam mechanical compression - NP herniates through radial tears AF, impinge exiting neural root (L5)

disc herniation

normal - allow/restrain movement, transmit load NP - higher fluid/proteoglycan, 85% water AF - higher collagen, rings bound by proteoglycan, 70% water age/repetitive load - NP loses water, disc dehydrates, AF fissures/tears, load less distributed, more vulnerable to posterolateral herniation (esp L4/5/S1) compresses nerve - mech compress/chem inflam, higher intraneural pressure, less blood flow, neural sensitivity

Lx Rx L5 + neural mechanosensitivity

L5 Sx - sensation (lateral calf, dorsum, big toe), motor (tib ant - DF, ext hallucis longus)

• pain buttock/lat calf/dorsum, p+n dorsum
• 'less reliable' - DF weak, tripping shows motor deficit neural mechanosensitivity
• compressed L5 sensitive to stretch/compress/high intrathecal pressure
• explains pain w/ cough, positive NxDx tests, difficulty walking

Lx Rx central sensitisation + movement

central sensitisation

• persistent nerve irritation decreases pain threshold, increases sensitivity to movement
• causes protective muscle guarding - avoidance gym/swim movement helps
• improves intraneural blood flow
• reduces inflam congestion
• restores normal nerve gliding
• reduces disc pressure in certain positions

DD peroneal nerve entrapment + why not

compression of common peroneal nerve at fibular head

• causes focal demyelination, slows conduction, causes sensory and motor deficits
• often from long kneel, legs crossed, trau,a why not
• sensory - dorsum and lateral shin (similar but no LBP)
• motor - foot drop (weak DF/eversion)
• reflex - normal
• NxDx - slump/SLR would be negative if nerve root not involved

DD S1 Rx + why not

mechanism - disc herniation S1 root, inflam increases sensitivity, compression decreases blood flow + increases pain why not - dermatomes - post thigh, post calf, lateral foot

• myotomes - PF weakness not DF
• reflex - reduced/absent achilles
• NxDx - SLR often positive so use reflex

DD spinal stenosis + why not

mechanism - narrowing central canal or lateral recess due to triple degen process

• 1 intervertebral disc less height/liquid, 2 FJ hypertrophy + osteophytes, 3 lig flavum thickens into foramen
• less space CE or nerve roots > neurogenic claudication why not - common bilateral LL Sx
• p+n diffuse > dermatomal
• pain high w/ext and low w/flex (narrows/opens canal)
• less walking tolerance relieved by sitting/leaning forward

outcome measures

• VAS
• numeric pain rating scale NPRS - leg and back pain separate
• ODI - well validated in Lx Rx, measure impact on daily function
• PSFS - walking quickly, gym attendance, swimming
• MMT
• timed heel walk test
• sensory mapping
• Tampa Scale Kinesiophobia TSK - fear av, relevant
• Lower Extremity Functional Scale LEFS - LL function, walking best 3 - ODI, TSK, PSFS

safety

• no red flags - Sx consistent w/nerve root irritation - safe to manage conservatively
• monitor for deterioration in motor function esp DF weakness - progressive worsening weakness is urgent medical review
• exercise in tolerable discomfort, avoid sharp/worsening pain
• no CES Sx - saddle, b/b, bilat etc

fear avoidance

• 'damage nerve w/exercise' explain nerves robust and recover well, irritation does not equal damage
• avoiding movement can increase sensitivity + time of recovery
• graded movements help nerves heal
• simple reassurance
• simple, achievable steps to increase confidence eg gentle walk or low load gym activity

adherence

• link to goals - gym/swim - meaningful
• simple program - 1 neural/1 strength, at home
• agree realistic dose - 10-15mins daily, avoid overwhelm
• clear instructions, check technique to increase confidence
• follow up and adapt plan - increase accountability

onward referal

not at present - Sx stable, unilat, consistent w/NR irritation

• CES - saddle, b/b, bilateral leg
• red flags
• new/worsening leg weakness
• unremitting night pain
• systemic Sx
• Sx unresponsive to treatment - liaise w/GP for med optimising
• consider imaging if would change management