Lumbar Radiculopathy assesment

Lumbar radiculopathy is a neurological condition caused by compression or irritation of a lumbar nerve root, producing motor, sensory, and reflex changes in the corresponding myotome and dermatome. Although pain is not part of the formal definition, patients commonly report radiating, sharp/electric pain, numbness, and paresthesia. The symptom experience is subjective and varies with a patient’s interpretation and pain beliefs.¹

Human spinal nerves. Illustration: Sheryl Tan, Faull L, Curtis A.Source: https://commons.wikimedia.org/wiki/File:Nervios_espinales.png – License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/).

Radiculopathy vs. Radicular Pain: they often coexist but can occur independently—radiculopathy may be present without pain, and radicular pain can occur without objective neurological signs.² Estimated prevalence is 3–5% of the population,³ ⁴ and it is among the most common reasons for referral to spine surgery.⁵ Among people with low back pain, 12–40% also show radiculopathy features.⁶

Common Etiologies

The most frequent cause is disc herniation with nerve root compression. Other causes include:

• Degenerative changes: spondylolisthesis, spinal stenosis, osteophytes

• Trauma: compression fractures

• Tumors within/adjacent to the canal

• Infections involving vertebrae or nerve roots

• Vascular causes: venous congestion, hemangioblastomas, AVMs⁶ ⁸

Red Flags — Immediate Referral

Refer urgently if any of the following are present⁹:

• Fever without clear source

• Unexplained weight loss

• New urinary or fecal incontinence/retention

• Saddle anesthesia

• Gait ataxia

• Prior or active malignancy

Body Charting & Symptom Mapping

Use a body chart and active exploration (palpation, provocation) beyond spontaneously reported areas to uncover latent or under-reported symptoms. This clarifies the radicular distribution and improves diagnostic precision.¹

Objective Examination — Core Elements

Myotomes: strength testing for segmental motor deficits

• Reflexes: patellar and Achilles; hyporeflexia may indicate root involvement

• Sensation: light touch/pinprick in dermatomal territories

• Upper motor neuron screen: Hoffmann, Babinski, ankle clonus to exclude central signs

• Neurodynamic tests: SLR, Slump (and Femoral nerve test for high lumbar roots)

• Lumbar A/P ROM: flexion, extension, lateral flexion/rotation (active & passive)

• Repeated movement testing: McKenzie/MDT principles as test–retest

• Segmental palpation & accessory motion: symptom reproduction, hypomobility/hyper-mobility

No single test is highly accurate alone. Combinations of historical features + clustered physical tests improve diagnostic value and guide management.¹⁰

Myotomes — Lower Limb

Nerve Root	Primary Movement (Key Muscle Action)
L2	Hip flexion
L3	Knee extension
L4	Ankle dorsiflexion
L5	Great toe extension
S1	Ankle plantarflexion
S2	Knee flexion (hamstrings)

How to test (manual muscle testing):Explain, position accurately, apply gradually increasing resistance for ~3 seconds (“hold, hold, hold”), grade 0–5, compare bilaterally, and record patient-reported asymmetry even when objective strength seems equal.

Dermatomes — Lower Limb

Dermatome	Typical Cutaneous Area
L1	Region around iliac crest and greater trochanter
L2	Anterior thigh (groin to mid-thigh/knee)
L3	Anterior thigh & knee; medial leg
L4	Lateral thigh, medial leg, dorsum of foot and hallux
L5	Postero-lateral thigh, lateral leg, dorsum of foot, medial sole, toes 1–3
S1	Posterior thigh & leg, lateral foot border

Light touch testing tips: patient supine/sitting, eyes closed; use fingertip/cotton; compare sides; use the same map consistently across patients.

Deep Tendon Reflexes

Reflex	Peripheral Nerve	Root Level	Strike Location	Expected Response
Patellar	Femoral n.	L2–L4	Patellar tendon (infrapatellar)	Knee extension
Achilles	Tibial n.	S1–S2	Achilles tendon	Ankle plantarflexion

Neurodynamic Testing

Positive when the patient’s familiar leg symptoms are reproduced (not merely tightness).

Straight Leg Raise (SLR)

• Supine; lift straight leg (ankle neutral).

• Positive: symptom reproduction ~30–70° hip flexion.

• Bragard’s (add ankle dorsiflexion) can increase neural load/differentiate.

Slump Test

• Sitting; thoracolumbar flexion + cervical flexion; extend knee & dorsiflex ankle.

• Repeat asymptomatic → symptomatic side.

• Positive: reproduction of concordant symptoms during sequence.

Femoral Nerve Stretch Test

• Prone (or sidelying); passively flex knee (and add hip extension).

• Positive: anterior thigh/groin symptoms—useful for L2–L4 involvement.

Repeated Movement Testing (MDT/McKenzie)

Goal: determine if leg pain centralizes (moves proximally toward the back), indicating mechanical responsiveness.

Key considerations

• Test multiple directions (not just extension): flexion, lateral shift, lateral flexion.

• Assess in loaded (standing) and unloaded (lying) positions.

• Use sufficient volume: often ≥10–15 repetitions are needed for change.

• Track: intensity, distribution (centralization/peripheralization), ROM, posture.

Centralization is a favorable prognostic sign and may directly inform treatment direction.

Clinical Notes for Practice

• Document baseline neuro status (myotomes, dermatomes, reflexes) to enable test–retest after interventions.

• Combine history clusters (e.g., leg pain > back pain, dermatomal numbness, myotomal weakness, positive SLR/Slump) with exam findings for better accuracy.

• Consider differential diagnoses (hip pathology, peripheral neuropathy, vascular claudication, referred pain from SIJ/hip) when the pattern is atypical.

• Use imaging judiciously—clinical course and response to treatment often guide need.

Sources:

1. Rainey N. Lumbar Radiculopathy Assessment Course. Plus, 2023.

2. Thoomes E, Falla D, Cleland JA, Fernández-de-Las-Peñas C, Gallina A, de Graaf M. Conservative management for lumbar radiculopathy based on the stage of the disorder: a Delphi study. Disabil Rehabil. 2023 Oct;45(21):3539-3548.

3. Berry JA, Elia C, Saini HS, Miulli DE. A review of lumbar radiculopathy, diagnosis, and treatment. Cureus. 2019:11(10).

4. Vanti C, Turone L, Panizzolo A, Guccione AA, Bertozzi L, Pillastrini P. Vertical traction for lumbar radiculopathy: a systematic review. Arch Physiother. 2021 Mar 15;11(1):7.

5. Berry JA, Elia C, Saini HS, Miulli DE. A review of lumbar radiculopathy, diagnosis, and treatment. Cureus, 2019;11(10):e5934.

6. Alexander CE, Varacallo M. Lumbosacral Radiculopathy. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan-. : https://www.ncbi.nlm.nih.gov/books/NBK430837

7. Amjad F, Mohseni-Bandpei MA, Gilani SA, Ahmad A, Hanif A. Effects of non-surgical decompression therapy in addition to routine physical therapy on pain, range of motion, endurance, functional disability and quality of life versus routine physical therapy alone in patients with lumbar radiculopathy; a randomized controlled trial. BMC Musculoskelet Disord. 2022 Mar 16;23(1):255.

8. Berthelot JM, Douane F, Ploteau S, Le Goff B, Darrieutort-Laffite C. Venous congestion as a central mechanism of radiculopathies. Joint Bone Spine. 2022 Mar;89(2):105291.

9. DePalma MG. Red flags of low back pain. JAAPA. 2020 Aug;33(8):8-11.

10. Van der Windt DA, Simons E, Riphagen II, Ammendolia C, Verhagen AP, Laslett M, et al. Physical examination for lumbar radiculopathy due to disc herniation in patients with low-back pain. Cochrane Database Syst Rev. 2010 Feb 17;(2):CD007431.

11. Functional Pain Management Society. Myotome testing by an expert: https://www.youtube.com/watch?v=UodWTD_IRb8 [last accessed 5/12/2023]

12. Functional Pain Management Society. Tendon reflex testing by an expert (DTR test). : https://www.youtube.com/watch?v=OACTm57eE5I

13. Pesonen J, Shacklock M, Rantanen P, Mäki J, Karttunen L, Kankaanpää M, et al. Extending the straight leg raise test for improved clinical evaluation of sciatica: reliability of hip internal rotation or ankle dorsiflexion. BMC Musculoskelet Disord. 2021 Mar 24;22(1):303.

14. John Gibbons. Straight Leg Raise (SLR) or Lasegue test for Sciatic nerve pain (Sciatica): https://www.youtube.com/watch?v=bX2yMWkartg

15. Maitland GD. The slump test: examination and treatment. Aust J Physiother. 1985;31(6):215-9.

16. The Physio Channel. : https://www.youtube.com/watch?v=L0R9fm5Swrk

    ↑ Butler D, Matheson J. The sensitive nervous system. Adelaide: Noigroup Publications; 2000.

17. Cunningham S. Lumbar Spine Evaluation Course. Plus, 2024.

18. John Gibbons. How to test the Femoral Nerve (Lumbar Plexus L2,3,4) or reverse Lasegue's: https://www.youtube.com/watch?v=cN0uou-nZH8

19. everydayPT. Femoral Nerve Testing (sidelying position). https://www.youtube.com/watch?v=nbhhewS5ZN8

20. Wetzel FT, Donelson R. The role of repeated end-range/pain response assessment in the management of symptomatic lumbar discs. The spine journal : official journal of the North American Spine Society. 2003;3(2):146–154.

21. osedale, R., Rastogi, R., Kidd, J., Lynch, G., Supp, G., & Robbins, S. M. (2020). A study exploring the prevalence of Extremity Pain of Spinal Source (EXPOSS). The Journal of manual & manipulative therapy, 28(4), 222–230. https://doi.org/10.1080/10669817.2019.1661706