Archive

Posts Tagged ‘pain’

An Actual (kind of…) Immaculate Conception

December 30, 2010 Leave a comment

Discoblog has released their top 10 weirdest science stories of the year, and number 1 is also one of my favourites.

It is a case report from the British Journal of Obstetrics and Gynaecology, entitled:

“Oral conception. Impregnation via the proximal gastrointestinal tract in a patient with an aplastic distal vagina. Case report.”

They have the full text on their blog here, but I will summarize.

A 15-year old girl is admitted to hospital with a stab wound to the abdomen, received during a knife fight between her ex-boyfriend and her new boyfriend. She was treated and released a few days later.

278 days after the incident, she came back to the hospital with severe abdominal pain. Turns out she was pregnant. However…

Inspection of the vulva showed no vagina, only a shallow skin dimple was present below the external urethral meatus and between the labia minora. An emergency lower segment caesarean section was performed under spinal anaesthesia and a live male infant weighing 2800 g was born

So the girl had no vagina. So how did she get pregnant?

Just before she was stabbed in the abdomen she had practised fellatio with her new boyfriend and was caught in the act by her former lover. The fight with knives ensued. She had never had a period and there was no trace of lochia after the caesarean section…

A plausible explanation for this pregnancy is that spermatozoa gained access to the reproductive organs via the injured gastrointestinal tract.

Yes, you read that right. She went down on her boyfriend, got stabbed, and the sperm went from her stomach into her reproductive system.

If that’s not miraculous, I don’t know what is. Although the author of the case study does say that

The fact that the son resembled the father excludes an even more miraculous conception.

Advertisements

Yet Another Acupuncture Experiment Overblown

November 30, 2010 4 comments

Acupuncture being performed. From Wikipedia

A presentation is being given today at the 96th Scientific Assembly and Annual Meeting of the Radiological Society of North America.

A couple of media outlets have jumped on this presentation, titled “Influence of Acupuncture on Pain Modulation during Electrical Stimulation: An fMRI Study“.

The headline in the Telegraph reads: Acupuncture’s effect ‘isn’t just psychological’

In the Daily Mail it reads: Acupuncture is no placebo and does relieve pain, say scientists

The Telegraph headline is misleading, and the Daily Mail headline is just plain wrong. And, as I’ll point out, both are overstating the findings of the study, as are the scientists who performed it.

So first off, fMRI stands for Functional Magnetic Resonance Imaging. It is a type of MRI scan which can determine which parts of the brain become “activated” by measuring the amount of blood flow to each part of the brain.

It is a fascinating field of study, and in a future post I will explain the physics of MRI, but for now lets just say that fMRI is (somewhat) able to tell which parts of the brain “turn on” when you do certain tasks.

So what happened in this particular study is this: the authors got 18 healthy volunteers and shocked their ankle with an electric shock to induce pain. At the same time, they imaged their brain using fMRI.

Next, they took the same 18 people, performed acupuncture on them, and then shocked their ankle again and took another fMRI of their brain.

They compare the two images, before and after the acupuncture, to see which parts of the brain light up (or don’t) to see if they could see any differences in how the brain reacts to pain stimuli with and without acupuncture.

And wouldn’t you know it? They did see a difference. Their conclusion:

Activation of brain areas involved in pain modulation was significantly reduced or modulated under acupuncture and the majority of the detected areas were not influenced by the analyzed covariate. However, left anterior insular cortex and orbitofrontal / superior frontal gyrus activation was modulated by stimulus intensity. We hypothesize that insula activation seems to be correlated to the stimulus and pain intensity while the importance of frontal activation increases during acupuncture and may be an acupuncture specific effect.

Essentially, they found that after the acupuncture, parts of the brain which control pain were not activated as strongly. Not only that, but the affective response to pain (the frontal cortex) was changed after the acupuncture as well. Pretty convincing right?

No. It’s not . First off, a similar response has been shown by Wager et al. in 2004 that placebos induce the same effect.

Second, it has also been shown that expecting pain can alter one’s response to pain. This study had the volunteers get their ankle shocked first, then they got acupuncture and had to be shocked again. They were expecting the pain, so this may have affected the results.

Third, there was no control group. A proper study should have had a placebo type of acupuncture, such as pricking the skin with toothpicks (which has been done before) or placing the needles at non-acupuncture points. Or they should have tried some other type of pain relief, like massage or relaxation prior to the second shock, to see if there was any difference.

Fourth, the study only had 18 volunteers. To make a claim that acupuncture works based on such a small group is irresponsible.

Fifth (geez, five points?!) fMRI is not easy to gather accurate conclusions from. The workings of the brain are affected by many things and brain responses can be non-localized.

I am not refuting the results of the study, only the conclusions drawn by the authors and the media. The data itself is not surprising. In fact, it is exactly what you would expect since placebos have shown similar results. But to draw the conclusion that this is an acupuncture specific effect from this data is fallacious.

Homeopathy “Tricks You” Into Feeling Better? *Facepalm*

November 17, 2010 1 comment

Homeopathy is a form of Complementary and Alternative Medicine which has been largely discredited by the medical community. At its core, it is the belief that by diluting a substance to extremely small amounts, often until none of the active ingredient remains in the final product, makes the remedy more potent.

It makes no sense, and it doesn’t work. Yet because of tradition and some unfortunate legislation in 1938 in the United States, Homeopathy is still around.

A study was published earlier this week in the journal Rheumatology. Some news outlets are saying that the outcome shows that homeopathy “tricks you” into feeling better. This made me feel like poor Captain Picard here.

The study examined 5 groups of patients suffering from Rheumatoid arthritis. It split these participants into 5 groups:

  1. Those that received consultation and individualized treatment from a Homeopath
  2. Those that received consultation and complex treatment from a Homeopath (complex treatment is giving the patient a group of standard homeopathic remedies which are not tailored specifically to the patient).
  3. Those that received consultation from a Homeopath but given a placebo.
  4. Those that received no consolation and given complex treatment.
  5. Those that received no consolation and given a placebo.

The groups were blinded as to whether they received a placebo or a real treatment, but obviously you couldn’t blind them to whether or not they received a consultation.

I won’t go into all the data analysis or statistics, but the results eventually state that there was no difference between the placebo treatment and homeopathic treatment, which is not surprising.

However, the authors go on to assert that there was a significant difference between those that received a consultation and those that didn’t, and that this is evidence for the efficacy of homeopathy.

From the Telegraph:

Dr Sarah Brien, the study’s lead author, said that while previous research had suggested homeopathy could help patients with rheumatoid arthritis, the study provided the first scientific evidence to show such benefits were “specifically due to its unique consultation process”.

There are a few problems with this. The first is that the study is fairly small, therefore the power of their results is not high enough to make any broad stroke conclusions about the efficacy of homeopathy.

Second, the group which received a consultation was not adequately compared to anything. Comparing a homeopathic consultation to no consultation, and then claiming that homeopathy made these people feel better is not a sound conclusion. The authors should have compared the group receiving a homeopathic consultation to a group which received some other form of personal consultation or experience, like speaking with a medical doctor or hell, even a motivational speaker!

Steven Novella gives a good explanation on Science-Based Medicine about the Hawthorne effect which can have a significant impact on a study. Having the personal experience of speakin to a person may make for a better patient outcome, but it certainly does not prove any efficacy of homeopathy itself.

Holy F@#$! That Hurt!

October 6, 2010 1 comment

I’ve been busy the last few days, but I have still been collecting interesting science news. Here’s one that really jabbed me. Pun TOTALLY intended.

A study published last year in Neuroreport found that swearing allowed people to withstand pain significantly longer than those who didn’t swear.

Why am I talking about this now? Because this study won the Ig Nobel Peace Prize, a prize awarded to research “that first make people laugh, and then make[s] them think.”

The researchers thought:

The observed pain-lessening (hypoalgesic) effect may occur because swearing induces a fight-or-flight response and nullifies the link between fear of pain and pain perception.

They did measure the heart rates of the subjects in this study, but they did not monitor any other biological effects. Basically they are saying that it is a complicated combination of  real physical effect (increased adrenaline and heart rate) and a simple placebo effect (decreased pain perception).

Whatever the cause, I let loose quite the string of explicits when I stub my toe on the same damn corner of the coffee table at least once a week! Grrr…