Back Pain – OSCE Case

If you'd like to support us, check out our awesome products:

Introduction

A 50 year old man presents to his GP with back pain. Work through the case to reach a diagnosis.

UK Medical Licensing Assessment (UKMLA)

This clinical case maps to the following UKMLA presentations:

  • Back pain
You might also be interested in our collection of 800+ OSCE Stations, including a range of primary care and history taking stations.

History

Presenting complaint

“This morning I was lifting a TV out of my car when I suddenly developed really awful back pain. It’s been there ever since and I’m struggling to deal with it.”

History of presenting complaint

Explore the details of the back pain

Use SOCRATES to gain further details about the patient’s back pain.

Site:

  • Where is the back pain?

Onset

  • Did it come on suddenly or gradually?

Character

  • What kind of pain is this? (e.g. sharp, aching, burning)
  • Is it continuous or intermittent?

Radiation

  • Does the pain move anywhere else?

Associated symptoms

  • Are there any other associated symptoms (e.g. weakness, numbness, saddle anaesthesia, urinary or faecal incontinence, weight loss, fevers, sweats)?

Timing

  • When exactly did it start?

Exacerbating/relieving factors

  • Does anything make it better or worse?
  • Is it worse when you walk, sit down or lay flat?

Severity

  • On a scale of 1-10, how bad is the pain? Is it getting better or worse?

Check if the patient has experienced similar symptoms previously

  • Have you experienced back pain in the past?
  • Was it similar to what you are currently experiencing?

For more information, see our guide to back pain history taking.

Patient’s response

“The back pain started as soon as I lifted the television this morning and I felt a click. There is a constant ache and then sharp pain whenever I try to bend. The pain is in the lower back and it does not shoot down the leg. Paracetamol, ibuprofen and a heat pack have helped a little bit, but not much. I’ve had the ‘usual’ joint aches here and there but nothing this bad ever. I don’t have any weakness or numbness and I’ve opened my bowels today without any issues, I’m also passing water fine. I haven’t noticed any weight loss, fevers or sweats. The pain is definitely worse when I bend, lying still seems to help a little bit. The pain is about 8 out of 10 at its worst.”

Other areas of the history

Past medical history:

  • Musculoskeletal conditions (e.g. previous fractures, osteoarthritis, osteoporosis)
  • Rheumatological conditions (e.g. ankylosing spondylitis)
  • Malignancy
  • Previous trauma
  • Other medical conditions
  • Allergies
  • Previous spinal surgery

Drug history:

  • Regular medication (e.g. steroids)
  • Over the counter drugs (e.g. analgesia)

Social history:

  • Accommodation (e.g. house, flat, bungalow)
  • Home situation (e.g. others living with the patient)
  • Level of functional independence
  • Current occupation
  • Smoking status
  • Alcohol history
  • Recreational drug use

Travel history:

  • Ask about travel to areas of high tuberculosis (TB) prevalence if considering TB as a cause (e.g. Pott’s disease).

Systemic enquiry:

  • Abdominal pain
  • Nausea and vomiting
  • Lower urinary tract symptoms
  • Haematuria
  • Weight loss
  • Appetite
  • Fevers

Patient’s response

“I have high blood pressure and I’m on lisinopril for that, but otherwise I’m fit and well as far as I know.”

“I live with my wife in a flat and neither of us smokes or drinks. I work as a lorry driver and I’m fully independent.”

“I haven’t travelled anywhere in years and I haven’t noticed any weight loss.”

Red flags

  • Back pain in those younger than 20 or older than 50
  • Non-mechanical pain
  • Thoracic pain
  • Saddle anaesthesia
  • Bladder dysfunction (e.g. urinary retention, incontinence)
  • Faecal incontinence
  • Limb weakness
  • Associated trauma
  • Weight loss
  • Fever
  • Structural abnormality of the spine

Clinical examination

If there were any history or examination findings suggestive of cauda equina syndrome, you would also need to perform:

If there were any history or examination findings suggestive of intra-abdominal pathology, you would also need to perform:

Clinical findings

  • Gait – the patient is walking slightly ‘stooped’ due to the pain
  • Palpation – there is point tenderness in the lower lumbar spine
  • Movement – there is limited range of spinal movement due to pain
  • Power – MRC grade 5/5 in both lower limbs
  • Sensation – normal sensation in all modalities
  • Reflexes – normal
  • Rectal examination – not performed

Differential diagnoses

  • Muscular strain
  • Vertebral fracture
  • Prolapsed intervertebral disc
  • Discitis
  • Ankylosing spondylitis
  • Spinal stenosis
  • Malignancy

It is also important to consider intra-abdominal and genitourinary pathology causing referred low back pain, especially in older patients:


Management

The GP adopts a ‘watch and wait’ approach, given the absence of neurological signs and the short duration of symptoms.

Given the presence of red flags in the history, this is a questionable decision.

The GP advises the following

  • Non-urgent physiotherapy review
  • Analgesia (paracetamol, NSAIDs and codeine)
  • A review appointment with the GP in two weeks
  • Safety netting (if the situation worsens, come back for an early review)
  • Avoid heavy lifting

Failure to improve

The patient presents one week later due to worsening pain and fatigue. He has spent most of the last week in bed, and his wife is very worried.


Investigations

  • FBC: raised WCC may suggest an infective cause, iron deficiency anaemia may suggest malignancy)
  • U&Es: taking NSAIDs and an ACE inhibitor, therefore at risk of acute kidney injury)
  • LFTs: ALP elevation may point towards skeletal disease – e.g. bony metastases)
  • Bone profile: hypercalcaemia – e.g. bony metastases)
  • CRP: raised CRP – e.g. discitis, ankylosing spondylitis)
  • ESR: raised ESR – e.g. ankylosing spondylitis)
  • Spinal X-rays: to screen for fractures and other bony deformities)

Investigation results

  • Hb – 105 g/L (130-170)
  • WCC – 8.5 x 109/L (4-11)
  • Neutrophils – 5.7 x 109/L (2-7.5)
  • Lymphocytes – 1.9 x 109/L (1.5-4)
  • Platelets – 190 x 109/L (150-400)
  • ESR – raised
  • Sodium – 137 mmol/L (135-145)
  • Potassium – 4.9 mmol/L (3.5-5)
  • Creatinine – 150 μmol/L (60-125)
  • Urea – 8.7 mmol/L (3-6.5)
  • Calcium (adjusted) – 3.43 mmol/L (2.15-2.5)
  • Phosphate – 0.8 mmol/L (0.7-1.5)
  • ALP – 250 u/L (60-150)
  • ALT/GGT – normal
  • Bilirubin – 12 μmol/L (3-17)
  • CRP – 12 (<5)

 

L4 wedge fracture
Lumbar spine x-ray 1

A wedge fracture of the lumbar spine (L4).

  • Primary hyperparathyroidism
  • Malignancy with bony metastases
  • Sarcoidosis
  • Tuberculosis
  • Parathyroid hormone (PTH) levels
  • Thyroid function tests
  • Serum protein electrophoresis
  • Urine protein electrophoresis (Bence Jones proteins)
  • Measurement of immunoglobulins
  • Vitamin D levels
  • HIV screen
  • Angiotensin-converting enzyme levels (sarcoidosis)

Not all of these investigations are warranted immediately (e.g. HIV/ACE), and the choice of investigations should be informed by clinical suspicion.

Intravenous fluids

  • NaCl (0.9%) can be used to rehydrate the patient and encourage urinary excretion of calcium.
  • Fluid balance should be closely monitored to avoid overloading the patient.

Bisphosphonates

  • Bisphosphonates (e.g. Pamidronate) reduce bone turnover and can be used for short-term treatment of hypercalcaemia, once patients have been rehydrated.
  • Pamidronate also has an analgesic effect on vertebral fractures.

Further management

The patient is admitted to hospital, and his nephrotoxic medications (ACE inhibitor and NSAIDs) are stopped. His hypercalcaemia is managed successfully with IV fluids and pamidronate.

Further investigations show the following:

  • PTH – 0.5 pmol/L (1.05 – 6.83)
  • IgG – 59 g/L (5.9-15.6)
  • IgA – 0.5 (0.6-5)
  • IgM – 0.3 (0.4-2.3)
  • Serum electrophoresis – a band in the gamma region is noted
  • Immunofixation – IgG Kappa paraprotein is detected totalling 52g/L

Diagnosis

Multiple myeloma

  • The most likely diagnosis is multiple myeloma (a.k.a. plasma cell myeloma).
  • Multiple myeloma involves the clonal proliferation of plasma cells.
  • An initiating event occurs which gives a specific plasma cell a survival advantage (e.g. chromosomal translocation). As a result, normal mechanisms to reduce proliferation are overcome, and the plasma cell clone begins to proliferate.

Features of myeloma

CRAB is a useful mnemonic to help remember the most common features of myeloma:

  • HyperCalcaemia – cytokines result in osteoclast dysregulation
  • Renal failure – light chains clog up the renal tubules
  • Anaemia – the bone marrow becomes overcrowded with plasma cells
  • Bone lesions – cytokines result in osteoclast dysregulation
  • A bone marrow aspirate and trephine biopsy looking for a clonal plasma cell proliferation are needed to confirm the diagnosis.
  • A skeletal survey is also required to stage the disease.
Multiple myeloma on bone marrow aspirate <sup>2</sup>
Multiple myeloma on a bone marrow aspirate 2

Symptomatic myeloma criteria

The below criteria must be met for a diagnosis of symptomatic myeloma: 3

  • Clonal plasma cells >10% on bone marrow biopsy or in a biopsy from other tissues.
  • A monoclonal protein (paraprotein) in either serum or urine (unless non-secretory, in which case there need to be >30% clonal plasma cells in the bone marrow).
  • Evidence of end-organ damage felt related to the plasma cell disorder (e.g. CRAB).

Asymptomatic myeloma

This type of myeloma is often referred to as smouldering myeloma. It differs from symptomatic myeloma because of the absence of end-organ damage.

The below criteria must be met for a diagnosis of asymptomatic myeloma: 3

  • Serum M paraprotein (IgG or IgA) >30 g/L or urinary M protein ≥500 mg per 24 hours and/or clonal bone marrow plasma cells 10-60%.
  • No myeloma-related organ or tissue impairment or amyloidosis.

Treatment

Myeloma is currently an incurable disease that is chronic, relapsing and remitting. Treatment is aimed at controlling the disease, prolonging survival and maximising quality of life.

Initial treatment

This man has symptomatic myeloma and therefore requires active treatment. 4

Treatment choice is based on the age and fitness level of the patient.

Younger patients (< 65 years or < 70 years and in a good clinical condition):

  • Induction chemotherapy (bortezomib & dexamethasone) followed by high-dose therapy with autologous stem cell transplantation (ASCT) is the standard treatment.
  • This would be the most appropriate choice for the patient in this scenario.

Elderly patients:

  • Chemotherapy alone without ASCT transplant
  • Bortezomib, melphalan and prednisone
  • Alternative regime – lenalidomide plus low-dose dexamethasone
  • Radiotherapy can be used if there is focal bony pain/plasmacytoma.

Maintenance

Lenalidomide has been approved as monotherapy for the maintenance treatment of younger adult patients with newly diagnosed myeloma who have undergone autologous stem cell transplantation. Maintenance therapy is not recommended for elderly patients.

Monitoring

Patients who have undergone myeloma treatment (and those with smouldering myeloma) should be reviewed at least every 3 months, including assessment of the following:

  • Myeloma symptoms and treatment side effects (e.g. fatigue, bony pain)
  • FBC, renal function, bone profile, serum immunoglobulins and serum protein electrophoresis

Reviewers

TeamHaem

@TeamHaem


References

  1. James Heilman, MD. Lumbar spine fracture. Licence: [CC BY-SA]. Available from: [LINK].
  2. KGH. Bone marrow image. Licence [CC BY-SA]. Available from: [LINK].
  3. Patient.info. Multiple myeloma. Updated May 2018. Available from: [LINK].
  4. Multiple myeloma: diagnosis, treatment and follow-up; ESMO Clinical Practice Guideline (2017). Available from: [LINK].

 

Print Friendly, PDF & Email