As a clinical practitioner, when a client presents to you, revealing the story of their injury, lighting up the present collection of presenting symptoms, you delve into the textbook of your clinical experience.
All you have learned is in there, but it has also built into it healthy suspicion, intuition and
a rogues' gallery of bizarre memorable maladies that will be seen once in a lifetime.
Diagnosis is the Sherlock Holmes of clinical experience. It is the sleuth inside let out on one more mystery to solve. You have your built-in Doctor Watson to smooth off the sharp edges of your grandiose ideas. He throws around the notions of doubt: what else could this be? Is there a red flag silently flapping in the breeze? A couple of years ago I attended a fascinating course, The Sherlock Holmes Approach to Finding Red Flags, where red flags indicate serious conditions masquerading as aches and pains. It's to every new patient's advantage that their physio is keeping on top of new research, and sniffing out medical curiosities that might jump out of rarity into reality. Something akin to Liverpool coming from three goals down to beat Barcelona 4-3 — a preposterous notion but discount it at your peril apparently.
Yes, I may have just talked up the everyday task of each clinician in physical medicine, but you don't just come to us for symptom relief. It is all very well to offer treatment, but treatment without justification is just recipe "care". We need to ask ourselves "what else could this be?" This is called differential diagnosis and it pokes and prods at the approach that treats first and asks questions later. It doesn't settle for the provisional diagnosis which may have come on a referral slip of paper. It inherently mistrusts, so that when you come to a conclusion you have fought hard in your mind to disprove it.
Let us consider the differential diagnosis for something many will likely experience: Jaw pain.
Ligament sprain — a supportive strap of tissue is injured. Often the obvious cause is trauma: glaringly obvious is someone's fist imparting nefarious directed force to the mandible or jawbone. It could also be the unnatural but necessary force required to extract a stubborn tooth, or a few hours in the dental chair. Whatever the case, the ligament offers a few telltale signs that lead you in that direction. The signs make sense and correlate with movement predictably.
Acute disc injury — the cushioning tissue between your jaw and skull can cause big symptomatic presentations. Clicking and locking are severely noticeable and can make it hard to eat, yawn or sleep. Often the disc on its own is not directly responsible, so it's worthwhile inspecting the ligaments here too.
The Nerves — In the head 12 nerves are located. Two of particular interest are the Trigeminal and the Facial. Trigeminal nerve irritation can come from a blood vessel wrapping round it causing jaw and face pain — Trigeminal nerve pain is one to catch you out, as it offers severe pain in the jaw region. Facial nerve palsy or Bells Palsy (no relative of mine) can create symptoms in similar areas, but is usually easy to thresh out — running eyes and motor weakness aren't jaw symptoms.
Muscles: masseter, temporalis, the pterygoids? It helps to know what they do and where they are. Usually they are involved because of movement limitation causing them to overwork. Helpful to know so you don't just resort to massage or trigger point approaches.
Osteoarthritis — a natural consequence of time and perhaps some long-term habits such as clenching, but not a major contributor to jaw dysfunction.
The less frequent problems are importantly held back for questioning, but usually have no part to play in the bulk of "crimes". Infection, malignancy or cancer, Eagles Syndrome (where a calcified ligament disturbs artery and nerve causing ringing in the ears and jaw pain) or auto immune disorders are the suspects you should rule out as a habit. Saying this, there is an adage that cautions the clinician not to see the bizarre in the everyday.
"When you hear hoofbeats, think horses, not zebras". This diagnostic realism is what keeps us grounded. If you didn't have this cornerstone, you might see the very unlikely as regular jaw troublers — they are not. So a trained diagnostician is looking at all the clues in your story to form a plausible answer. It is never as simple as "your jaw is out". So if you want to get your jaw diagnosed, you really need to go through the carefully selected appropriate tests to rule in or out whats really going on.