Definition
LBP is defined as pain or discomfort below the costal margin and above the inferior gluteal folds, with or without referred leg pain
Localised = Axial pain
Radiating pain = Radicular
Spondylolysis = Fracture of pars interarticularis. Bilateral in 80% of cases. 90% at L5
Facet arthritis = localised pain across the back with radiation occasionally into buttock or thighs. Discomfort reproduced by lumbar extension and rotation.
Lumbar stenosis = Commonly in over 60yo and by large central disc herniation.
Other possible pathology includes: disc bulging, facet capsular hypertrophy, ligamentum flavum, spondylolisthesis, and osteophytes. Wide based gait and absent ankle reflexes can occur (though less than 50%). 20-30% of patients will be asymptomatic
Remember - sitting and lying opens up lumbar region given symptom relief. Thus, walking (neurogenic claudication) becomes uncomfortable as the nerves become ischaemic
Sacroiliac joint dysfunction = pain over the superior aspect of the buttock adjacent to the L5 vertebrae. Pain reproduced with lumbar flexion and extension. Tests include: pelvic distraction/compression, gaenslens, FABER and thigh thrust
Presentation
- CLBP is a heterogenous condition with multiple potential pathologies
- 80-85% of back pain is 'non-specific' - It cannot be related to a biological origin
- There are probably about 20 different 'phenotypes'
- There is a significant lack of clear guidelines and evidence is often poor-quality
History factors
- Red flags must always be explored including: Incontinence, saddle anaesthesia, nocturnal pain, fever, progressive leg weakness)(THIS NEEDS EXPANSION)
- Pharmacological therapies tried (e.g. opioids, substance use disorder)
- Occupational history and work performance issues
- Patient's beliefs about the problem
Epidemiology
- Leading cause of job related disability in the US (and likely Australia?)
- 80% of people will experience back pain in their lifetime
- 20% of people will experience pain at 1 year after initial pain
- 80-90% of acute back pain will self-resolve
- L5 nerve root is most common affected in radicular pain
Risk factors
- Age 50-69yo
- Lower high school education (?? More physical jobs)
- Low household income (Again - more physical job?)
- Depression
- Poor sleep
Pathophysiology
Examination
- Gait assessment (?antalgic)
- Visual inspection of the back (can mark pain - remember L4-5 at top of iliac crests)
- Palpation of the back
- Focused neurological examination
- Assessment of lumbar range of motion
- Use of special manoeuvres (SLR, FABER)
- Reflexes: Knee jerk (L2, L3, L4), Ankle jerk (S1, S2)
Sensory:
L2-proximal antero-medial, thigh;
L3-medial, knee
L4-medial, mid leg
L5-lateral, mid leg
S1 lateral, foot
Assess motor function:
L2, L3, hip flexors
L3, L4, knee extensors
L4, L5, foot dorsi-flexors
S1, S2, foot plantar flexors
S2, S3, S4 - Rectal tone
Romberg’s sign (patient standing, eyes open, steady, then falling with eyes closed)
- indicates a proprioceptive problem either in the periphery (eg, olyneuropathy) or centrally (eg, spinal cord dorsal columns).
L5 Radiculopathy = Diminished foot dorsiflexion, toe extension, and both foot inversion and eversion.
S1 Radiculopathy = Sensory change along posterior leg and bottom of foot. Weakness on plantar flexion and possibly hip extension and knee flexion. Ankle reflexes may be absent
Investigations (if required)
- Xray's
- CT = For osseous structures of the spine
- MRI = Best for marrow, intervertebral discs, soft tissues, and spinal canal structures
T1-weighted sagittal
T1-weighted image obtained following the administration of intravenous gadolinium
T2 fat-suppressed or short tau inversion recovery (STIR) sagittal
T2-weighted sagittal and axial sequences
Joint nerve blocks, such as lumbar facet joint injections, have been shown to diagnose effectively 89.5 % of patients and are able to provide pain relief in 80 % of patients (Pampati et al, 2009).
Treatment
- Initially physical therapy is critically important
- NSAIDs can be utilised
- Aims are to return to a point of function
- Interventions, acupuncture etc - used to facilitate active exercise therapy
(Core, gluteus stretching, posture, deep hip flexors)
- Address bad occupational habits
- Epidural steroid injections provide modest benefit lasting 3 mths (el-Khoury GY & Renfrew, 1991).
- Surgery is a final option (Chen et al, 2017)
Discectomy for a herniated disc.
Decompressive laminectomy for spinal stenosis, kyphoplasty.
Vertebroplasty for compression fractures.
Arthrodesis for spinal fusion.
Prognosis
Golden pearls
References / Articles / Resources
Argoff, C. E., Dubin, A., Pilitsis, J., & McCleane, G. (2009). Pain management secrets E-Book. Elsevier Health Sciences.
Chen K.Y., Shaparin N., Gritsenko K. (2017) Low Back Pain. In: Yong R., Nguyen M., Nelson E., Urman R. (eds) Pain Medicine. Springer, Cham. https://doi-org.ezproxy.anzca.edu.au/10.1007/978-3-319-43133-8_121
el-Khoury GY, Renfrew DL. Percutaneous procedures for the diagnosis and treatment of lower back pain: diskography, facet-joint injection, and epidural injection. AJR Am J Roentgenol. 1991;157(4):685–91.
Pampati S, Cash KA, Manchikanti L. Accuracy of diagnostic lumbar facet joint nerve blocks: a 2-year follow-up of 152 patients diagnosed with controlled diagnostic blocks. Pain Physician. 2009;12(5):855–66
Essential readings:
Apkarian AV, Robinson JP. 2010. ‘Low back pain’. IASP Pain Clinical Updates XVIII (6):1–6. PDF
Bogduk, N, Fraifeld, EM. 2010. ‘Proof or consequences: who shall pay for the evidence in pain medicine?’. Pain medicine 11 (1): 1–2. EZ
Bogduk, N. 2005. ‘A narrative review of intra-articular corticosteroid injections for low back pain’. Pain medicine 6 (4): 287–96. EZ
Chou, R, Huffman, LH. 2007. ‘Medications for acute and chronic low back pain: A review of the evidence for an American Pain Society/American College of Physicians clinical practice guideline’. Annals of internal medicine 147: 505–14. OA
Schiltenwolf, M, Fischer, C, Kunz, P. 2011. ‘How perfect studies may be? Comment on Peng et al. ‘A randomized placebo-controlled trial of intradiscal methylene blue injection for the treatment of chronic discogenic low back pain’. Pain 149: 124–9’. Pain 152 (4): 954–5. PDF
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