Radicular Pain Differential Diagnosis
Sciatica and other forms of Radicular pain are frequently presented to general practitioners and musculoskeletal physiotherapists. 60% of patients who presented with a mix of back and leg pain were diagnosed with sciatica in recent primary care research. Clinicians must be able to correctly identify radicular pain and tell it apart from other illnesses due to the high prevalence of sciatica and the pain and functional limitations it is linked with. This first of two-part series will help you comprehend what radicular pain is, how it manifests, and a list of ailments that might mimic radicular pain and should be taken into consideration when making a differential diagnosis. Let’s get into some definitions, causes, and presentations first, though.
Presentation and Definition
The lumbosacral nerve roots (L4-S1) are irritated or compressed to generate radicular discomfort, which improves nerve function. This is used to describe a nerve that is abnormally excitable and manifests as paraesthesia, pain, hyperalgesia, allodynia, hyperreflexia, and/or muscular spasms. Pain frequently begins in the buttock and spreads to the lower leg and knee.
SCIATICA
This is distinct from lumbar radiculopathy, a nerve root issue that also causes a loss of nerve function. Diminished impulse conduction, which might manifest as hypoesthesia, anaesthesia, weak or absent reflexes, muscular weakness, and/or reduced feeling, is what this term denotes. Individuals frequently come with characteristics of both illnesses, such as painful radiculopathy, which is unfortunate for practitioners because patients don’t always fit into both categories. It’s crucial to keep in mind that real radicular pain is a very severe disease that may be quite upsetting, and some patients even report losing their sense of self.
The research on sciatica is often not well-defined. Whether you are a physiotherapist who recently graduated from college or has been in the field for a while, you have probably come across or heard of someone who has complained about sciatica. But how can we be certain that it is sciatica? How can we be certain that the issue isn’t coming from the hip, the sacroiliac joint, or—oh, how horrifying—the dreadful piriformis muscle? Let’s examine some radicular pain risk factors and causes to assist determine whether people may actually have a genuine nerve root disorder.
Risk Elements
It’s crucial to comprehend the risk factors and root causes of the issue in order to correctly diagnose someone with radicular discomfort. Lifepoint hospital did a fantastic job of outlining this in the Radicular Pain Masterclass on the Physio Network. Be sure to read it if you want a detailed understanding of the pathophysiology, history, and treatment of radicular pain. They divided risk variables and their root causes into the two categories listed below.
(The Kindling)Distal :
- Smoking
- Obesity
- Manual work Work
- Bending down
- Driving a lot
- Moderate walking
- Mental stress
- Poor job satisfaction
Proximal (The Fire):
- Disc lesion
- Spinal/Recess stenosis
- Spondylolisthesis
Although not a complete list, these are crucial factors to take into account as part of a thorough evaluation that also includes your subjective and physical exam.
Exactly how is sciatica identified?
The clinical presentation, which includes the patient’s subjective symptoms and the results of the physical examination, is used to make a diagnosis of sciatica. There is no particular test for sciatica, although a number of favourable screening results raise the possibility that it exists. Unless a more serious disease is anticipated or the patient has not reacted as expected to conservative therapy, imaging is rarely used to make a diagnosis. However, if the patient arrives at your clinic after having had imaging done, by all means, check to see if your assessment confirms the findings of the imaging.
Sciatica’s main warning signs and symptoms are as follows:
- The dominance of leg pain (more than back pain)
- Location of the leg pain (e.g. below the knee)
- Dermatomal pattern
- Paraesthesia and/or sensory loss aligning with the spinal root
- Myotomal changes
- Reflex changes
- Leg pain when coughing, sneezing, and taking deep breaths
- Gradual onset
In your physical examination, the below are possible findings:
- Unilateral motor weakness (particularly dorsiflexion if L5 is affected, leading to foot drop) Absent tendon reflexes
- Positive SLR (if negative, this reduces suspicion of sciatica)
- Positive cross-over test
- Increased finger-floor distance (>25cm)
By checking the patient for injuries, cancer, or significant infections, the practitioner must be able to rule out dangerous pathology. Consider if your main diagnosis of radicular pain is true or whether the pain is emanating from a source other than the nerve root if your index of suspicion for ominous pathology is low. The table below lists additional diseases that might imitate radicular discomfort.
Condition | SUB- FINDINGS | OBJ – FINDINGS |
LUMBAR RADICULOPATHY
|
· LOWER BACK PAIN
· UNILATERAL MOTOR WEAKNESS · NO LEG PAIN |
· POTENTIAL SENSORY DEFICITS
· MOTOR DEFICITS · ALTERED TENDON REFLEXES · POSITIVE NEURO-DYNAMICS |
PERIPHERAL ARTERY DISEASE | · ACHE
· BURNING IN LEGS · AGGRAVATED BY WALKING · EASED WITH REST |
· PAIN REPRODUCED WITH WALKING |
MERALGIA PARAESTHETICA | BURNING ANTEROLATERAL THIGH
NON-MECHANICAL SYMPTOMS |
NEGATIVE -SLR
NIL – REPRODUCTION WITH LUMBAR MOVEMENTS POSITIVE- FEMORAL TEST |
GTPS | PROXIMAL LATERAL HIP PAIN
SLEEPING ON A PAINFUL SIDE |
GRIMALDI’S CLUSTER |
HIP OA | STIFFNESS IN EARLY MORNING (LESS THAN 30MIN)
PAIN/STIFFNESS IN GROIN BUTTOCK LIMPING PAIN PUTTING ON SHOES/SOCKS |
C- SIGN
LOSS OF INTERNAL ROTATION POSITIVE- FABER test
|
SIJ
|
– | LASLETT cluster |
PIRIFORMIS/DEEP GLUTIAL SYNDROME | DIFFUSE BUTTOCK/ POSTERIOR THIGH PAIN
PAIN ON SITTING |
ACTIVE PIRIFORMIS CONTRACTION & STRETCH TESTS |
AVN OF THE HIP | LONG TERM STEROIDS
No MOI |
CLEAR HIP |
FOCAL NEUROPATHIES
(Tarsal Tunnel)
|
NEURO DESCRIPTORS IN THE FOOT | COMPLETE FULL NEURO EXAM |
INFLAMMATORY / METABOLIC CAUSES | SPONDYLITIS
DIABETES ANKYLOSING |
– |
Cauda equina syndrome may be present and patients should be referred for urgent medical care if they experience saddle anesthesia, bladder problems, loss of tone in the anal sphincter, impaired sexual function, and/or severe and increasing neurological impairments. For a list of cauda equina syndrome warning signals, see the graphic below:
CAUDA EQUNIA SYNDROME WARNING SIGNS
|
· LOSS OF FEELING/PINS AND NEEDLES BETWEEN YOUR INNER THIGHS OR GENITALS. |
· NUMBNESS IN OR AROUND YOUR BACK PASSAGE OR BUTTOCKS. |
· ALTERED FEELING WHEN USING TOILET PAPER OR WIPING YOURSELF. |
· INCREASING DIFFICULTY WHEN YOU TRY TO URINATE. |
· INCREASING DIFFICULTY WHEN YOU TRY TO STOP OR CONTROL YOUR FLOW OF URINE. |
· LOSS OF SENSATION WHEN YOU PASS URINE. |
· LEAKING URINE OR RECENT NEED TO USE PADS. |
· NOT KNOWING WHEN YOUR BLADDER IS EITHER FULL OR EMPTY. |
· INABILITY TO STOP A BOWEL MOVEMENT OR LEAKING. |
· LOSS OF SENSATION WHEN YOU PASS A BOWEL MOTION. |
· CHANGE IN ABILITY TO ACHIEVE AN ERECTION OR EJACULATE. |
· LOSS OF SENSATION IN GENITALS DURING SEXUAL INTERCOURSE. |
Is the pain referred or radicular?
You could be thinking, “Well, my index of suspicion for something nefarious is low here. Do I need to know if this is a nerve root problem or not?” at this point. This is a legitimate concern, albeit it might not matter to many patients. These are the patients that spontaneously heal within the anticipated time limits and improve without the assistance of a physiotherapist. To give the patient the greatest and most tailored treatment choices available, it is crucial that our diagnosis be as precise as possible if a patient isn’t recuperating as predicted and may need more intrusive therapy.
RADICULAR VS. REFERRED PAIN
RADICULAR | REFERRED |
LEG WORSE THAN BACK PAIN | BACK PAIN WORSE THAN LEG PAIN |
NEURO DESCRIPTORS | POORLY LOCALISED |
POSITIVE SLR | DULL ACHE |
BELOW KNEE | NEGATIVE SLR |
LOSS OF FUNCTION | |
WELL LOCALISED | |
SHOOTING | |
DERMATOMAL |
Objective Evaluation
A neurological examination should be a part of your objective evaluation to look at the nerve’s operation. This should entail testing motor control, reflexes, and light touch. It is important to note that only 30% of the nerve is evaluated by these examinations. Consider using a pinprick or a hot/cold gadget to measure the temperature of the remaining 70% of the nerve.
Conclusion
You now have a better understanding of the definition, causes, risk factors, and how to evaluate someone for radicular pain, which brings us to the subject of differential diagnoses of radicular pain. We have discussed the significance of taking into account dangerous diseases, disorders that might mimic radicular pain, and other pathologies in your differential diagnosis.