The Diagnostic Process in Low Back Pain
The Diagnostic Process
The overarching goal is essentially to find out what is wrong
- Take a patient-centred, thorough history.
- Formulate differential diagnoses, problems not to be missed, red flags, yellow flags based on the history findings.
- Construct a directed neuro-musculo-skeletal examination.
- Perform a directed neuro-musculo-skeletal examination.
- Formulate an evidence-based working diagnosis.
- In partnership with the patient, formulate a management plan.
- Identify the prognosis and its modifying factors from the patient’s lifestyle and other.
- Post management, reassess and establish a definitive diagnosis.
TAKING A HISTORY:
Taking a history from a patient is a skill necessary for examinations and afterwards as a practicing doctor/ chiropractor/ psychologist, no matter which area you specialise in. It tests both your verbal and non-verbal communication skills as well as your knowledge about what to ask.
- Introduce yourself, identify your patient and gain consent to speak with them. Should you wish to take notes as they proceed, gain their permission to do so.
- Presenting complaint: this is what the patient is requesting assistance with.
HISTORY OF PRESENTING COMPLAINT (HPC):
- Gain as much information as you can about the specific complaint.
- Site: where is the pain?
- Onset: When did the pain appear? Was it constant, intermittent, gradual or sudden?
- Character: what is the pain like? E.g. sharp, burning?
- Radiation: Does it radiate/ move anywhere?
- Associations: is there anything else associated with the pain, e.g. sweating, vomiting?
- Time course: does it follow any time pattern, how long did it last?
- Exacerbating/ relieving factors: Does anything make it feel better or worse?
- Severity: How severe is the pain on a scale of 1-10.
PAST MEDICAL HISSTORY (PMH): Gather information about a patients other medical problems (e.g. surgery)
MEDICATION HISTORY (MH):
- Find out what medications the patient is taking, including dosage and how often they are taking them, e.g. once a day, twice a day etc.
- At this point it is a good idea to find out about allergies.
FAMILY HISTORY (FH): Gather information about the patient’s family history, e.g. genetic conditions that may be hereditary.
SOCIAL HISTORY (SH): BUILD RAPPORT
- This is the opportunity to find out a bit more about the patient’s background. Remember to ask about smoking and alcohol. Depending on the PC it may also be pertinent to find out whether the patient drives, e.g. following an MI a patient cannot drive for a month. You should also discuss whether they have taking any illicit illegal substances.
- Also find out who lives with them, you may find they are the primary carer for a child or elderly parent, thus your duty would be to ensure that they are not neglected should your patient be admitted/remain in hospital.
SUMMARY OF HISTORY:
- Complete your history by reviewing what the patient has told you. Repeat back the important points so that the patient can correct you if there are any misunderstanding or errors.
- You should address what the patient thinks is wrong with them and what they are expecting/ hoping for from the consultation. A useful acronym is ICE, Ideas, Concerns and Expectations
PATIENT QUESTIONS AND FEEDBACK: During or after taking their history, the patient may have questions that they want to ask you. It is very important that you don’t give them any false information. As such, unless you are absolutely sure of the answer it is best to say that you will look into it and get them more information (e.g. leaflets) about what they are asking.
DIFFERENTIAL DIAGNOSIS: THE HISTORY
“Possible causes” are not the same as “differential diagnoses”
The distinguishing of a particular disease or condition from others that present similar clinical features. They refer to the likely alternative diagnoses of a particular presentation.
The aim of the process of a differential diagnosis is to arrive at the most likely diagnosis, while not missing or losing sight of other likely or serious alternative diagnoses.
It is a process that we employ on a fluid or continuous basis throughout the diagnosis and management of a patients and their condition. That is, as we take a history, perform an examination, obtain test results (radiology, bloods, urine, etc.), monitor the response to our management or learn of or observe a change in presentation.
This mean that we can often proceed with management of a ‘working diagnosis” while other differential diagnoses are either further investigated or kept on the ‘back burner’ of your clinical mind.
CLINICAL KNOWLEDGE, UNDERSTANDING AND REASONING:
Clinical reasoning requires a knowledge and understanding of the possible conditions underlying various types of presentations. It is from this that we can make sense of the information we glean from the history, examination, further investigation, trial or therapy.
THE HISTORY: This is the evidence you utilise to try and make some clinical sense regarding the events that have occurred and what is going on.
We ask further questions such as: have you been having pins and needles, numbness or weakness in the legs, etc.
Conceptual clinical thinking:
It is important to think of things in relation to concepts rather than solely off things you’ve learnt about, for instance a fever primarily indicates the possibility of an infective process, prolonged morning stiffness suggests possibility of an inflammatory process and constant unrelenting pain suggest bone or visceral disease.
This type of thinking helps to flag some differential pathways to be considered.
POINTS TO REMEMBER:
The aim of the process of differential diagnosis is to arrive at the most likely diagnosis, while not missing or losing sight of other likely or serious alternative diagnoses.
It is a process that we employ on a fluid or continuous basis throughout the diagnosis and management of a patient and their condition. That is, as we take a history, perform an examination, obtain test results (radiology, bloods, urine etc), monitor the response to our management, or learn of or observe a change in presentation.
This means that we can often proceed with management of a ‘working diagnosis’ while other differential diagnoses are either further investigated or kept on the ‘back burner’ of your clinical mind.
Sometimes we can rule out things of concern even if we can’t put our finger on a specific diagnosis... This can be reassuring for the patient, especially in the context of a patient who is anxious after having seen many practitioners but has yet to be given a definitive diagnosis for their problem.
PROBLEMS NOT TO BE MISSED: (PNTBM)
- ‘PNTBM’ These are issues/conditions/suspicions that you have uncovered and identified for follow-up and possible management and/or referral.
- Smoking in a patient presenting with suspicious spinal pain (metastases from lung cancer).
- Diabetes in a patient presenting with bilateral foot paraesthesia (diabetic peripheral neuropathy).
- Hypertension in a patient presenting with headache (progressing cerebral aneurysm).
'Red flags' are alarm or warning symptoms, signs and near- patient diagnostic tests that suggest a potentially serious underlying disease.
History of cancer, Unexplained weight loss, Worsening pain when supine and/or at night (constant night pain at rest), Age >50 or <16 years.
History of significant trauma (major trauma or less severe in the elderly/osteoporotic), Intravenous drug abuse, Recent bacterial infection or fever or chills, Immune suppression (HIV, transplant, corticosteroids), Saddle anesthesia, Bladder or bowel dysfunction, Neurological deficit in either or both lower limbs (especially if progressive), Persistent symptoms for >4 weeks (recurrent presentations, worsening pain).
‘Yellow flags’ are psychosocial indicators suggesting increased risk of progression to long-term distress, disability and pain. Yellow flags were designed for use in acute low back pain.
Belief that pain and activity are harmful, Sickness behaviours, Low or negative moods, mental illness, Treatment that does not fit with best practice – eg passive v participation, Problems with compensation system, Previous history of back pain with time off work, Problems at work, poor job satisfaction, Overprotective family or lack of social support.
WORKING DIAGNOSIS AND THE LINGERING DIFFERENTIAL DIAGNOSIS:
- You will usually have also retained one or more of your differential diagnoses for:
- further investigation; or
- to keep on the ‘back burner’ for further consideration if need be.
- Further consideration will often follow new information coming to hand, such as that elicited from:
- ongoing history, observations and examinations,
- investigation results; or
- response to management.
IMPORTANCE OF A WORKING DIAGNOSIS:
- The formulation of a working diagnosis via the differential diagnosis process and directed examination is very important for the following reasons:
- During the process, you will have considered the patient’s presentation in a thoughtful, systematic and reasoned way.
- This in turn means that:
- Any serious aetiology is likely to have been revealed (had signs and/or symptoms been present and assuming the patient’s history was reliable);
- You will have referred out in a timely manner for further investigation of any potentially serious condition, thus avoiding the harm that might arise from unnecessary delays;
- You will have most likely made a correct determination of the patient’s condition/injury and will therefore be in a better position to:
- Plan treatment with an understanding of the likely prognosis (what response to expect) and what outcome measures are appropriate;
- Know whether the patient should be referred for alternative or co-management
- You will have fall-back differentials to reconsider as a potential working diagnosis should the response to management not be as effective as you had expected;
- You are able to confidently and honestly reassure the patient as to what the nature of their condition is and whether there are any signs you should monitor or warn them of;
- Other chiropractors (locums, associates etc) or student practitioners can quickly establish what to expect or look for if they should be the next practitioner seeing the patient.
- It also means that:
- You have practised in accordance with:
- Your ethical responsibility; and
- Your legal obligations to provide a reasonable standard of care;
- You are in a position to communicate with other professionals (health, lega and insurance) in a more professional and effective way.
STEPS TOWARDS A WORKING DIAGNOSIS:
- The directed examination is designed to test the validity or likelihood of the differential diagnoses
- As you perform each test in your directed examination, think about the differential diagnosis you are wanting information on (testing for);
- Test results are not always ‘black and white’, therefore you should try to interpret the ‘strength’ of what you are finding as you are performing the test;
- Also take on board other findings you discover while performing the test, eg tissue swelling, tenderness etc that might not have been evident on your initial inspection.
- If your test result is not what you were expecting (ie, a strong differential on the basis of the history), make sure the test is appropriate for that particular patient and that you are performing the test appropriately... ie, does it need to be modified for that particular patient;
BUT DON’T ANCHOR
- By the end of your examination, you will usually have found that the evidence in support of one of your differential diagnoses is stronger than for the others;
- This differential diagnosis will become the nuts and bolts of your working diagnosis (needs a bit of tweaking with details eg, acute, chronic etc);
- Your working diagnosis will inform your management plan, the prognosis and the outcome measures;
- Further investigations may still be required to confirm the working diagnosis or to investigate the likelihood of other potentially serious differential diagnoses;
- In most cases, treatment can still be commenced despite referring out for further investigations.
- Even though tests may be available for confirmation of a particular working diagnosis, this does not necessarily mean that they need to be performed...
- You need to weigh up the pros and cons for that particular patient and their particular presentation:
- What is the likely benefit of performing the investigation
- What will be the likely impact on the outcome?
- What are the risks of not performing the investigations and the likelihood of the risks eventuating? Are you able to take steps to minimize these risks?
- Is it appropriate to have an initial trial of therapy? For how long?
FINAL WORKING DIAGNOSIS:
The final form of the working diagnosis should be:
- Specific and concise; and
- Time Frame
- Acute, subacute, chronic
- Idiopathic, post traumatic, overuse, exacerbation
- Mild, moderate, severe.
- Grade I,II,III
- Grade 1,2,3
It should also:
- Account for the presenting complaint
- Account for all complicating factors
- Account for all significant associated symptoms (ie referral, paresthesia)
DIFFERENTIAL DIAGNOSIS AND WORKING DIAGNOSIS
In-text: (Differential Diagnosis and Working Diagnosis, n.d.)
n.d. Differential Diagnosis And Working Diagnosis. [online] Available at: <http://differential diagnosis and working diagnosis> [Accessed 13 August 2020].
This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.