The test clears the test. It does not clear the nerve.
I had a week where the literature kept making the same point from three directions, and I'll own that I went looking for it. A meta-analysis of the straight leg raise across almost eight thousand patients that could not confirm or rule out the root. A surgical cohort where the symptoms sat one level below the MRI because the plexus itself sits in a different place in some people. Twelve seasons of English football where everyone has been doing their Nordics and the hamstring burden keeps climbing. Different papers, one lesson. The single test tells you about the single test. The exam has to carry the decision.
Also this week: two trials on how often to needle, and one pneumothorax that showed up three hours after a session that probably looked fine. Let's go.
I get asked about dose constantly. Clinicians want a number. The consensus paper gives you a principle instead, dose by irritability and tolerance, and says outright that more needling does not mean better outcomes. This week two trials put a frequency number next to that principle, and I think they show both halves of it.
Ninety young adults with chronic neck pain, randomized to electroacupuncture three times a week, once a week, or a waiting list, four weeks, same two points, same thirty minutes. Both needle groups beat the waiting list. Three times a week beat once a week on the Northwick Park, on VAS, on the McGill, and on pain tolerance. It did not beat once a week on pressure pain threshold. Then at the four-week follow-up, with the needle gone, the only advantage left was the VAS. The frequency bought pain relief, and most of what it bought did not hold on its own.
Second trial, knee osteoarthritis, eighty-four patients, warm needle acupuncture five days a week versus twice a week for two weeks. Five a week won on WOMAC pain by about three points, on stiffness, on function, and on active range by eleven degrees. Adverse events were the same. No sham, no follow-up past the two weeks.
Both are acupuncture trials, not trigger point work, and I'm reading them with that in mind. Here's what I take from the pair. Early in an irritable presentation, frequency matters, and it matters for the reason we talked about in Issue 09 with the tibialis posterior trial: the change the needle makes is gone by seventy-two hours. Three sessions a week never lets that window close. Once a week lets it close four times. Why the pain tolerance separated and the pressure threshold did not, I honestly don't know. What the neck trial can't tell you is whether the three-a-week group did better because the needle got more chances or because those patients were in a clinic moving three times a week, and that is exactly the question we should be asking of our own schedules.
One more brick, from the 13-trial electrolysis meta-analysis that's been sitting in the bank: running current through the needle did not beat the plain needle for myofascial pain at any time point. More current is not more effect. More sessions, for a while, is. Neither is the treatment. The loading you put through the window is.
For an irritable neck or knee, front-load the dose: two or three sessions in week one if the tissue tolerates it, then re-test range and pressure threshold before every reload. By week three the needle should be getting rarer and the loading heavier. If you're still needling three times a week in week four, you built a dependency, not a program. Re-test, and if it's better, load it.
Okay, this one I'd frame and hang in every clinic that has ever written “SLR negative, lumbar cleared” in a note.
Nee, Boyd, Sierra-Silvestre, and Coppieters, people who have spent careers on neurodynamics, pooled twenty-four studies of the straight leg raise for lumbosacral radicular pain. Seven thousand eight hundred and twenty-one patients for the SLR, nearly four thousand for the crossed SLR. Sensitivity and specificity were typically below 0.80 no matter how you defined a positive test or what you compared it against, imaging, electrodiagnostics, surgery, or a clinician's diagnosis. The crossed SLR was specific, above 0.85, and nearly blind, sensitivity under 0.35. The likelihood ratios for both produced shifts in post-test probability the authors call small and unimportant. Certainty low to very low. And then the honest line at the end: the estimates won't improve until the reference standards capture the mechanosensitivity component of radicular pain. They're saying the test and the gold standard are measuring different things.
Here is why that matters for us. The straight leg raise tests one thing, whether a nerve under tension is sensitized enough to complain. The patient I keep writing about, the silent radiculopathy, the elbow or the plantar fascia or the hamstring with a root that is compressed and under-fed but not yet shouting, has a nerve that is not sensitized. It's a hose that has been stepped on, not a hose that's on fire. A tension test was never going to find it. Dermatomes find it. Myotomes find it. A reflex that's a grade down finds it. And the thing that confirms it is treating the segment and watching the periphery change.
A second paper from a Japanese surgical group makes the exam even more necessary. One hundred and twenty-seven disc herniation patients plus twenty-five cadavers. The patients whose symptoms sat one level below the MRI lesion had shorter twelfth ribs, a conus that sat higher, and more often a visible L4 branch running into the lumbosacral trunk. In the cadavers, rib length and that branch's thickness tracked each other almost perfectly, r of minus 0.86. The plexus is prefixed or postfixed in some people, and the dermatome you find on the skin will not match the level on the film. You treat the exam, not the picture.
And from outside our profession: a neurology group published a two-part teaching review titled, I'm not making this up, “The Shoulder,” which opens by calling the shoulder uniquely susceptible to neurological disorders and an early marker of underlying pathology. Radiculopathies, plexopathies, scapular dyskinesis as a neurological sign. A ten-patient surgical series this week put a number on the cost of missing that: seven months, on average, from chronic shoulder pain to someone finding the suprascapular nerve.
Stop clearing the spine with one test. Run the pinwheel, the myotomes, and the reflexes on every limb complaint, and write down the level you found, not the level the MRI shows. Where they disagree, treat the level you found, re-test the periphery, and if it changed, load the muscle that was downstream.
How it walks in: a player, or a weekend sprinter, third hamstring strain in a year, same leg, same spot, and they tell you in the first minute that they've been doing their Nordics. They have. That's the problem with the story.
The Football Association just published twelve seasons of surveillance on English men's domestic football. Four hundred and sixteen team-seasons, nearly sixteen thousand time-loss injuries, over two million hours of exposure. Hamstring was the most common diagnosis and the single greatest burden, forty days lost per thousand hours. And the muscle injury burden in matches rose ten percent per season. Twelve seasons of the best prevention programs money can buy, and the line goes up. I'll say what I think that means, and it's my opinion: for a lot of these athletes, the hamstring was never the problem.
Ask the RMO question out loud. What is driving this, and is it central or peripheral? Remember the BJSM cohort from a couple of weeks ago: in ninety-six Division I football hamstring strains, the sciatic nerve sat inside the edema in seventy-five of them, seventy-eight percent, and when the nerve was fully involved the player was out about twelve days longer. A matched cohort put lumbar spine pathology at nearly double the odds of a hamstring injury diagnosis. And a piriformis block resolved eighty-five percent of patients who carried both a clinical lumbosacral radiculopathy and gluteal tenderness. The root and the downstream muscle coexist. I said it in Issue 08 and I'll say it again because it's the whole model: the muscle was protecting the nerve, and under load it's the muscle, the part that heals, that gives. The hamstring is the fuse. You can make a fuse thicker. If the short circuit is at L5, it blows again.
The assessment, every time. L5 and S1 dermatomes with the pinwheel. Myotomes: hip extension, knee flexion, plantar flexion, great toe extension, compared side to side and compared to what this athlete should produce. Achilles reflex. Slump. Palpate the sciatic nerve in the posterior thigh and ask if that's their pain. The straight leg raise too, but you read Focus 2: a negative one clears nothing. Then the strength test, and this is where this week's paper lands. One hundred and one patients at least four months out from ACL reconstruction, most with a hamstring graft, tested four ways. On the seated isokinetic dynamometer, limb symmetry was ninety-eight percent and eighty percent of them passed the ninety-percent clearance mark. On a prone isometric test at ninety degrees of knee flexion with the ankle plantarflexed, symmetry was forty-four points lower and three percent passed. Same patients, same day. A second study in adolescents showed the symmetry index moving because the good leg got stronger, not because the operated leg changed. The test you pick decides whether the deficit exists. The hamstring you cleared on a seated machine is the hamstring that tears in the sprint. And from Issue 09, remember the under-20 footballers: forty percent still below the minimal detectable change at seventy-two hours while the group average said recovered.
One honest gap: the new JOSPT hamstring guideline is in the references because you'll be asked about it. I have not yet seen whether a lumbar or neural screen appears anywhere in it. If it doesn't, that tells you something too.
Before you touch the hamstring, run the L5-S1 exam. If it lights up, even a grade, needle the segment first, the lumbar multifidus and the glute med that answers to it, and re-test the myotome and the prone isometric before you go anywhere near the thigh. Clear the athlete on the test that can see the deficit, not the one that flatters it. Then load: Nordics, yes, and sprint exposure, because a hamstring that's never asked to lengthen at speed in the clinic will do it for the first time on the pitch.
Three hours later.
Your hands are not the problem. I'd put money on the hands in this case report being fine too. A young woman with Ehlers-Danlos and refractory cluster headache had posterior thoracic needling, went home, and about three hours later developed pleuritic chest pain and progressive shortness of breath. A 2.8 centimeter apical pneumothorax. Aspiration took off about 450 milliliters of air, the CT showed no bullae, and it resolved on its own within a day. One case, Level V, and the kind of case that happens to competent people.
Two things to sharpen. Before the needle: hypermobility and connective tissue history are a screening question over the thorax, not a curiosity, and so is how much tissue sits between your needle and the pleura on this particular patient. After the needle: the sentence you say before they leave. Chest pain, breathlessness, a cough that wasn't there this morning, tonight or tomorrow, you call, you don't wait. Say it every time you work the upper trap, the rhomboids, the paraspinals above T12. The patient who leaves fine is the one the sentence is for.
The regulators won't write that sentence for you. A scan of all ten Canadian physiotherapy colleges this year found that not one of them meets the published dry needling recommendations and none has evidence-based guidelines. Norway's compensation registry for chiropractic care over twelve years, one approved claim per million consultations, found the serious approved claims were the neurological and vascular ones. The rule book is thin and the serious events are the ones your screen prevents. If you already ask the two questions and say the one sentence, teach it to the clinician down the hall. That's the growth at your level: not the hand, the habit.
A negative straight leg raise clears the straight leg raise. That's all it clears.
A small ask. Send me the hamstring that keeps tearing. The one who does the Nordics. Tell me what the L5-S1 exam showed, and if no one ran it, tell me that too. The Special Topics edition on headaches goes out this Thursday. When it lands, run one headache patient through the decision tree and tell me whether it fit or whether it needs another branch.
Forward this to someone who needles. Every past issue is at tacticalphysio.com/category/the-briefing.
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