What should be checked before relying on a WPI figure?
Check maximum medical improvement, the body area, objective findings, the NSW Guideline chapter and any NSW modification before relying on a percentage.
Can this page calculate your percentage?
No. WPI depends on an assessor, maximum medical improvement, objective findings and the NSW Guidelines. This page is general information only.
Permanent impairment assessment
How permanent impairment is assessed for Nerve damage, peripheral nerve injury, sensory loss and motor loss
Nerve damage may attract WPI when the evidence identifies the nerve involved and shows objective sensory, motor or mixed impairment. Tingling, numbness, burning pain or weakness can be important clinically, but WPI usually needs a recognised nerve pattern and reliable clinical findings.
What injuries can happen to this body part?
- Median, ulnar, radial, axillary or digital nerve injury in the upper limb
- Common peroneal, tibial, sciatic, femoral or other lower limb peripheral nerve injury
- Nerve injury after fracture, dislocation, laceration, surgery, crush injury or compartment-type injury
- Entrapment or compression neuropathy, such as carpal tunnel, where supported by clinical findings
- Nerve-root compression from the spine, which should be analysed as radiculopathy rather than a peripheral nerve lesion
Symptoms and findings that matter
- The named nerve and whether the deficit is sensory, motor or mixed
- Whether sensory loss follows a recognised nerve distribution, dermatome or digital nerve pattern
- Clinically measurable motor loss, weakness, wasting, loss of power or reflex change where relevant
- Whether EMG/NCS supports the diagnosis and matches the clinical picture
- Whether the issue is peripheral nerve injury, spinal nerve root radiculopathy, spinal cord injury, CRPS or musculoskeletal pain
- Whether digital nerve lesions need the separate hand/finger method, including two-point discrimination
What investigations are usually relevant?
- Treating specialist report and final impairment assessment at maximum medical improvement
- Imaging, pathology, audiology, ophthalmology, respiratory, nerve or functional testing that fits the body system
- Operative reports, discharge summaries, rehabilitation records and objective clinical measurements where relevant
How WPI is assessed for this body part
- Nerve damage may attract WPI when the evidence identifies the nerve involved and shows objective sensory, motor or mixed impairment. Tingling, numbness, burning pain or weakness can be important clinically, but WPI usually needs a recognised nerve pattern and reliable clinical findings.
- Assessment source: NSW Guidelines Chapter 5 nervous system, plus the relevant upper extremity, lower extremity or spine chapter depending on whether the problem is a peripheral nerve, spinal nerve root or digital nerve lesion.
- The assessor should explain maximum medical improvement, the body-system chapter, the method selected, any NSW modification, and why the objective findings fit that method.
How movement affects the assessment
- ROM is not the proof of nerve damage. A worker may have restricted movement because of pain, joint injury, tendon injury or guarding, but nerve WPI needs the relevant nerve method.
- If a pure peripheral nerve injury is assessed, the same functional loss should not usually be rated again through abnormal motion or grip loss for the same limb.
- Digital nerve injuries are different from major peripheral nerve injuries. They may require static two-point discrimination and conversion from digit to hand, upper extremity and WPI.
NSW nervous system assessment rules
Brain and central nervous systemCerebral functions are considered by domains such as consciousness/awareness, cognition, communication, emotional/behavioural change, movement and cranial nerve findings.
Peripheral nervesPeripheral nervous system impairment is assessed through the relevant upper extremity, lower extremity or spine method rather than as a vague neurological label.
Do not double-rateThe assessor should be specific and avoid rating the same functional loss under overlapping cognitive, behavioural, musculoskeletal or nerve categories.
Objective evidenceStable clinical findings, specialist examination and relevant testing matter. Symptoms by themselves may affect capacity but may not establish WPI.
Upper limb nerve and carpal tunnel rules
Sole peripheral nerve injuryIf the upper extremity impairment results solely from a peripheral nerve injury, do not also rate abnormal motion for that same upper extremity.
Peripheral nerve tablesUse AMA5 Table 16-15 together with Tables 16-10 and 16-11 for peripheral nerve lesions, as adopted by NSW.
Clinical judgementThe examiner must choose an appropriate percentage within the severity range. The maximum value is not applied automatically.
Carpal tunnel after surgeryPost-operative carpal tunnel syndrome is assessed in the same way as carpal tunnel without operation.
Grip strength and ROM in CTSWhere carpal tunnel is assessed as a nerve condition, grip loss and loss of ROM are usually not separately rated for CTS itself.
Digital nerve and finger sensory method
Digital nervesEach finger has radial-side and ulnar-side digital nerves. The affected side, finger, and length of sensory loss matter.
Two-point discriminationDigital nerve sensory loss is determined by static two-point discrimination: 6 mm or less is no sensory impairment; 7 mm to less than 15 mm is partial sensory loss; inability below 15 mm is total sensory loss.
Conversion pathDigital impairment is converted to hand impairment, then upper extremity impairment, then WPI using AMA5 Tables 16-1 to 16-3 as adopted.
Example onlyA full-length partial ulnar digital nerve loss in a ring finger is given in the AMA companion example as 10% ring finger impairment, converting to 1% hand, 1% UEI and 1% WPI.
Neuroma example onlyA painful digital neuroma example with 50% sensory deficit of the index radial digital nerve converts to 15% index finger impairment, 3% hand, 3% UEI and 2% WPI.
NSW lower limb peripheral nerve rules
Assess by nerve where possibleLower limb peripheral nerve injury should be assessed by the nerve method rather than gait where possible.
Motor, sensory and dysaesthetic componentsSeparate motor, sensory and dysaesthetic components are combined under the NSW lower limb nerve method.
Posterior tibial nerveBecause posterior tibial nerve is not listed in AMA5 Table 17-37, NSW calculates it by subtracting common peroneal ratings from sciatic nerve ratings.
No combination with gait/atrophy/strength/CRPSLower limb peripheral nerve impairment is not combined with gait derangement, muscle atrophy, muscle strength or CRPS where the Guidelines prohibit overlap.
NSW radiculopathy criteria, in practical terms
Criteria countThe NSW Guidelines generally require two or more criteria, with at least one major criterion, before radiculopathy is concluded.
Reflex, motor or sensory findingsLoss or asymmetry of reflexes, anatomically localised weakness, or reproducible sensory impairment can be relevant when they fit the nerve root distribution.
Nerve tension, wasting and imagingPositive nerve root tension, muscle wasting/atrophy, and imaging consistent with the clinical signs can also be relevant.
Pain aloneRadicular pain or sensory symptoms that follow an anatomical pathway but cannot be verified by neurological findings do not alone constitute radiculopathy.
Practical WPI examples
- A worker with foot drop after a fibular head injury may need common peroneal nerve analysis, supported by motor findings and EMG/NCS if obtained.
- A worker with ring and little finger numbness after elbow trauma may need ulnar nerve assessment rather than a general hand-pain label.
- A worker with leg pain from a lumbar disc prolapse may need radiculopathy analysis if dermatomal sensory loss, weakness or reflex change fits the level and side.
- A finger laceration affecting a digital nerve needs the finger sensory method, not a broad “nerve damage” percentage.
Evidence checklist
- A clear diagnosis and the body area being assessed
- Records showing the condition has reached maximum medical improvement, if that is the issue
- Specialist reports, imaging reports and treating notes relied on by the assessor
- Objective findings on examination, not only symptoms described by the injured person
- A work and treatment chronology explaining the injury, treatment, surgery and recovery path
- Any previous injury, degeneration, congenital issue or non-work cause that needs apportionment considered
- Neurologist or surgeon report naming the nerve
- EMG/NCS where obtained
- Sensory map or dermatomal findings
- Motor testing, reflex findings and wasting measurements
- Operative report, trauma records or imaging explaining mechanism
- Hand therapy or rehabilitation notes where function is affected
What usually does not increase WPI
- Assuming a scan result automatically gives a WPI percentage
- Confusing pain, disability or inability to work with permanent impairment
- Ignoring maximum medical improvement before arranging an assessment
- Using an AMA5 table without checking whether the NSW Guidelines modify or replace it
- Double counting the same impairment through two methods when the Guidelines require one method
- Calling non-specific tingling a ratable nerve injury without objective findings
- Treating MRI findings alone as nerve WPI when symptoms and signs do not match
- Confusing peripheral nerve injury with spinal nerve-root radiculopathy
- Counting the same sensory deficit under both nerve and musculoskeletal methods
Assessment source
Assessment source: Assessment source: NSW Guidelines Chapter 5 nervous system, plus the relevant upper extremity, lower extremity or spine chapter depending on whether the problem is a peripheral nerve, spinal nerve root or digital nerve lesion.
This section is source-backed general information. It is not a WPI assessment and is not legal advice.
- SIRA NSW Workers Compensation Guidelines for the Evaluation of Permanent Impairment: Source for the NSW assessment framework, MMI, AMA5 adoption, NSW modifications and exclusions.
- SIRA nervous system chapter: Source for nervous system assessment concepts including brain, spinal cord and peripheral nerve impairment.
- SIRA upper extremity chapter: Source for NSW upper extremity assessment rules and AMA5 Chapter 16 adoption/modification points.
- SIRA lower extremity chapter: Source for NSW lower extremity assessment rules, gait derangement limits and NSW-modified lower limb tables.
- SIRA spine chapter: Source for NSW spine assessment rules, DRE method, radiculopathy criteria and surgery modifiers. The NSW spine chapter excludes the ROM model.
- SIRA DRE definitions of clinical findings: Source for clinical findings used to place a spine condition into a DRE category.
Related injury and claim pages
- Common injury evidence hub
- Work injury claims NSW
- Claim process
- Compensation and entitlements
- Ask about an impairment issue
- NSW Injury Claim Evidence, Documents and Templates - This library helps injured people organise incident, medical, income, correspondence and daily-impact records into a clear working file, without presenting any checklist or template as an official form.
- NSW Injury Claims by Location - NSW Injury Claims accepts enquiries from across NSW. The claim pathway depends on how the injury happened, while phone, online and electronic document handling can make an initial enquiry possible without creating a false impression of premises in every region.
- Bladder, Bowel and Sexual Function Neuro WPI Assessment NSW - Neurological permanent impairment assessment guide with NSW Guideline source notes.
Need a practical claim check?
If an impairment percentage, medical assessment or insurer decision is affecting your NSW injury claim, send the decision or report for a practical review. This is general information only and does not guarantee any result.
Request a free claim checkAssessment scope for Nerve Damage WPI Assessment
The assessment scope for Nerve Damage WPI Assessment should be stated precisely before any percentage is considered. The file should identify whether that label describes the primary diagnosed condition, a symptom of another injury, a regional overview or one component of a broader impairment. Findings from another body area or diagnosis should not be transferred without explanation. The report should connect the stated condition to the correct NSW Guideline chapter, objective findings, treatment history and any permitted combination or apportionment method. This distinction is particularly important where similar page labels cover different clinical questions.
- Confirm the diagnosis and body area being assessed as Nerve Damage
- Separate condition-specific findings from overlapping symptoms or injuries in another body area
- Check that the selected NSW Guideline chapter and method match the condition actually assessed
- Explain any combination, apportionment or exclusion rather than relying on the page label alone
Clinical boundary for this WPI guide
“Nerve damage” is a broad description, not an assessment method. This guide helps classify whether the evidence points to a peripheral nerve, nerve root, plexus, spinal cord, brain or another neurological problem before a chapter is selected. The report should not infer location from symptoms alone. It should connect examination, imaging and electrodiagnostic evidence to a diagnosed lesion and explain which more specific assessment pathway applies.
- Clarify whether the problem is central, root-level, plexus-level or peripheral
- Do not use numbness or pain alone to identify the nerve lesion
- Compare clinical distribution with imaging, EMG and nerve-conduction evidence
- Move to the specific neurological or body-region method once the lesion is identified
Start with maximum medical improvement
Permanent impairment should generally be assessed when the condition is stable and unlikely to change substantially in the next year. Treatment, surgery and rehabilitation history may affect whether the timing is appropriate.
Use the NSW Guidelines first
The NSW Guidelines adopt AMA5 in many areas, but NSW modifications prevail. Do not assume an AMA5 table applies without checking the NSW chapter and any public SIRA clarification.
Keep the assessment practical
A useful assessment file separates diagnosis, objective findings, surgery history, work capacity issues, apportionment questions and the body-area method used by the assessor.
Ask about an impairment issueDocuments and records
Injury evidence to organise early
The useful records depend on how the injury happened, when symptoms were recorded and how treatment or work capacity changed.
- Date, location and short description of the injury event
- Medical certificates, reports, scans, treatment records or hospital documents
- Employer, insurer, police, incident or venue records where relevant
- Photos, witness details, dashcam or other supporting material if available
- Income, superannuation, work capacity or leave records where relevant
- Letters, emails, claim numbers and decisions already received
Common questions
Injury evidence questions
Short general answers only. The right next step depends on the facts, dates and documents.
Is WPI the same as being unable to work?
No. WPI is a medical impairment measure. Work capacity, weekly payments, damages, treatment disputes and TPD issues are separate questions, although the evidence may overlap.
Does pain alone create a WPI percentage?
Not by itself. NSW workers compensation excludes AMA5 Chapter 18 on pain. Chronic pain is assessed through the underlying diagnosed condition where the Guidelines permit it.
Can secondary psychological symptoms be added to physical WPI?
In NSW workers compensation, secondary psychiatric or psychological impairment is not assessed as permanent impairment. Primary psychological impairment is assessed separately and is not combined with physical WPI.
Injury pathway enquiry
Not sure which claim type matches the injury?
Start with how the injury happened, what medical records exist and how work or daily activity has changed. The same injury can sit in different pathways.