Lumbar Spondylosis

Age related degeneration of the lumbar spine: disc dehydration and height loss, annular fissures, osteophytes, facet joint osteoarthritis, ligamentum flavum hypertrophy, and spondylolisthesis, leading to low back pain and, in some patients, spinal canal or foraminal narrowing (lumbar spinal stenosis).

• Radiographic features are almost universal in older people: disc degeneration is found in about 35% of asymptomatic people aged 20 to 39 and above 90% of those over 60. Imaging findings correlate poorly with symptoms.
• Low back pain has a lifetime prevalence above 70%, and degenerative change is a contributor in most chronic cases. The most common affected levels are L4-L5 and L5-S1.
• Risk factors: age, obesity, physical labour with heavy lifting and vibration, smoking, sedentary lifestyle, genetic factors, previous injury, and psychological distress.
• Most acute episodes improve within 6 weeks (about 90%), but recurrence is common (about 60 to 80% within a year).

• Axial back pain: dull ache worse with prolonged standing, extension, twisting and heavy lifting, with morning stiffness settling within 30 minutes, and pain referred to the buttock and posterior thigh (not past the knee). Paraspinal tenderness and reduced range of movement. Neurological examination is normal.
• Lumbar spinal stenosis (neurogenic claudication): leg and buttock pain, heaviness or weakness on standing and walking, relieved within minutes by sitting or leaning forward (shopping trolley sign), and better when cycling. Leg symptoms are usually bilateral, and examination can be normal at rest.
• Radiculopathy: leg pain in a dermatomal pattern (L5 with great toe dorsiflexion weakness, S1 with plantarflexion weakness and an absent ankle reflex, L4 with quadriceps weakness and a reduced knee jerk), a positive straight leg raise (pain on lifting the straight leg between 30 and 70 degrees) and a positive crossed straight leg raise.
• Differential diagnosis: muscle strain, facet joint syndrome, sacroiliac joint dysfunction, disc herniation, vertebral fracture, spondyloarthritis, peripheral arterial disease and vascular claudication (leg pain with walking, relieved by standing still, with absent pulses), hip osteoarthritis, trochanteric pain syndrome, diabetic neuropathy, spinal infection, tumour or metastasis, abdominal aortic aneurysm, kidney stones, and pancreatic or gynaecological disease.
• Red flags: cauda equina features (saddle numbness, urinary retention or incontinence, bowel dysfunction, bilateral leg weakness, sexual dysfunction), progressive weakness, fever, unexplained weight loss, a history of cancer, trauma, age above 50 with new pain, night and rest pain, immunosuppression, and intravenous drug use.
• Complications: chronic pain and disability, spinal stenosis, spondylolisthesis, nerve root compression, and cauda equina syndrome (rare).

• Clinical, with neurological examination (power, sensation, reflexes, straight leg raise, gait), peripheral pulses, hip examination and an assessment of psychosocial risk factors (yellow flags).
• No imaging is needed for non-specific back pain without red flags in the first 6 weeks. Request imaging for red flags, progressive neurological deficit, suspected stenosis or a surgical question.
• X-ray (standing anteroposterior, lateral, and flexion extension views) shows disc space narrowing, osteophytes, spondylolisthesis and instability. MRI is the investigation of choice for radiculopathy, stenosis, red flags and before surgery. CT for bone detail.
• Blood tests for suspected inflammatory, infective or malignant disease: full blood count, CRP, ESR, calcium, alkaline phosphatase, HLA-B27, and protein electrophoresis. Bone density where osteoporosis is possible.
• Nerve conduction studies and electromyography when the neurological pattern is unclear. Ankle brachial index if vascular claudication is possible.

• Education: reassure about the benign course, encourage early return to normal activity, and avoid bed rest beyond 1 to 2 days.
• Analgesia:
  • Paracetamol 1 g orally 6 hourly (maximum 4 g daily, 3 g in the elderly or in low weight).
  • Naproxen 500 mg orally 12 hourly (or ibuprofen 400 mg 8 hourly, or diclofenac 50 mg 8 hourly, or etoricoxib 60 to 90 mg daily) with food for the shortest effective time, usually 1 to 2 weeks, with gastroprotection where needed. Topical diclofenac 1% gel 2 to 4 g 3 to 4 times daily.
  • Short course of muscle relaxant for acute spasm, 5 to 7 days: tizanidine 2 mg 8 hourly (increasing to 36 mg daily maximum), cyclobenzaprine 5 to 10 mg at night, or methocarbamol 1500 mg 6 hourly, with caution in elderly patients.
  • Weak opioid only for severe pain over a few days (tramadol 50 mg 6 to 8 hourly, maximum 400 mg daily).
  • Chronic pain: duloxetine 30 mg daily increasing to 60 mg daily, or amitriptyline 10 to 25 mg at night. Gabapentinoids have limited benefit in axial pain and are used for radicular pain (gabapentin 300 mg at night titrated to 900 to 1800 mg daily, pregabalin 75 mg 12 hourly increasing to 150 mg 12 hourly).
• Exercise and physiotherapy: core stabilisation, hip and trunk strengthening, walking, swimming, cycling, flexibility work, McKenzie-type directional exercises, and graded activity. Treat stenosis with flexion based exercises and cycling.
• Weight loss, smoking cessation, ergonomic changes, and cognitive behavioural approaches for chronic pain.
• Epidural steroid injection for radicular pain not settling after 4 to 6 weeks (triamcinolone 40 mg or dexamethasone 8 to 10 mg under imaging guidance), with short term relief of about 2 to 12 weeks, and use only a small number of injections per year.
• Surgery:
  • Cauda equina syndrome: emergency MRI and decompression within 24 to 48 hours.
  • Radiculopathy with progressive or severe motor deficit, or disabling pain persisting after 6 to 12 weeks: microdiscectomy or decompression.
  • Lumbar spinal stenosis with disabling neurogenic claudication after 3 to 6 months: laminectomy or decompression (fusion for instability or spondylolisthesis).
  • Fusion or disc replacement for axial pain from degenerative disc disease has limited evidence and is reserved for selected patients after at least 12 months of failed rehabilitation.
• Special groups:
  • Elderly: lower doses, avoid cyclobenzaprine and prolonged NSAID use, falls risk review, and check bone density.
  • Diabetes: monitor glucose after steroids, and separate neuropathy.
  • Pregnancy: physiotherapy, support belts, paracetamol and positioning. Avoid NSAIDs after 20 weeks.
  • Renal impairment: avoid NSAIDs, and reduce gabapentin and pregabalin.
  • Anticoagulation: hold under specialist guidance for epidural injection.
• Follow up: review at 2 to 4 weeks and at 6 to 12 weeks. Refer urgently for red flags and cauda equina features. Refer to spinal surgery or pain medicine for persistent radiculopathy, stenosis, or chronic pain after 3 months.