Thursday, August 27, 2015

Pectus Excavatum complications - beware neck strike during barbell Clean

I am deformed

Current Management of Pectus Excavatum [jf: depressed sternum associated upper chest]

Pectus excavatum (PE) is one of the most common anomalies of childhood. It occurs in approximately 1 in every 400 births, with males afflicted 5 times more often than females. PE is usually recognized in infancy, becomes much more severe during adolescent growth years, and remains constant throughout adult life. Symptoms are infrequent during early childhood, but become increasingly severe during adolescent years with easy fatigability, dyspnea with mild exertion, decreased endurance, pain in the anterior chest, and tachycardia. The heart is deviated into the left chest to varying degrees causing reduction in stroke volume and cardiac output. Pulmonary expansion is confined, causing a restrictive defect.

Repair is recommended for patients who are symptomatic and who have a markedly elevated pectus severity index as determined by chest X-ray or computed tomography scan…. Operation rarely takes more than 3 hours, and hospitalization rarely exceeds 3 days. Pain is mild and complications are rare, with 97% of patients experiencing a good to excellent result. The new minimally invasive Nuss repair avoids cartilage resection and takes less operating time, but is associated with more severe pain, longer hospitalization and a higher complication rate, with the bar remaining for 2 or more years…

My chest wall deformity is moderately severe, not as impressive as the wikipedia photo. A correction attempt was made at age 15 or so, but without the reinforcing “bar” used now. The post-operative pain then was not “mild”, it was exquisite — at least during breathing. The collapsed lung or two probably didn’t help. (I suspect my surgeon was pleased I survived). The deformity recurred, but my operative experience cured my psychic distress. I decided having an “ant’s swimming pool” wasn’t so bad after all.

Reading the above description it seems I can blame my unimpressive athletic career on my chest wall. Come to think of it, I did feel quite tired this morning on the fourth round of 400 meter sprints and as-many-reps-as-possible box-jump-over burpees. [1]

All of which is a prequel to new knowledge. I’ve figured out why I’m the only person at CrossFit who tends to hit their neck when doing a barbell “Clean”. With most people, even with poor technique, the upper chest pushes the bar away from the throat. With me it directs the bar towards my throat.

So there you go. For all the other persistent Pectusoids out there, if you are doing a barbell Clean pay attention to hitting your mid-body target and work on your technique — your pectorals will not save you.

[1] Sarcasm here should hint that this abstract’s disability description is debatable. In reality it is unclear how much cardiopulmonary compromise there is, and whether surgery really helps. Some articles suggest it helps cardiac function but worsens pulmonary function. There are big nocebo (deformity) and placebo (surgery) effects that make outcome evaluation difficult.

Update 8/31/2015: After writing this I realized I have a genuine CrossFit disability. I can’t do an “Rx” pushup, because I can’t touch my upper chest to to the ground (lower chest gets in way, not to mention my shoulders and head). During WODs I use an Ab Mat as a target, but I couldn’t do that in competition.

Tuesday, August 25, 2015

Mountain biking: A good sport for heavy kids?

I help out with a High School mountain biking team; it’s a team #1 rode with last year. (He might be first special needs student to compete in a NICA high school race, though I wonder about the Utah league.) It’s a sweet deal — I do adult things, carry the first aid kit, and help with team communications; in turn I get to ride with a great group of adults and kids while I get quality coaching by listening and practicing with our riders. #1 helps too, I’ve made it part of his post-high school “transition” training.

One of the things I've heard from the coaches is that heavy kids tend to do well with mountain biking. The bike takes a lot of weight off knees and hips and, by necessity, these kids have powerful legs. Weight isn’t a big disadvantage on the downhills. Being heavy does make climbs harder, but that work boosts conditioning. Heavy kids who go to practice lose fat and gain muscle, so they improve faster than slimmer riders. That rapid improvement is a powerful reinforcer. If they persist they keep the powerful leg muscles and lose fat — and become quite competitive.

I see the logic. It would be interesting to get some data, but I couldn’t find any studies in the medical literature. It could be a fun research topic. 

[1] He may be the only special needs student, so far, to compete in high school mountain bike races.

Wednesday, August 19, 2015

Amazon reviews show a Shimano SPD pedal has a safety defect. Do Amazon and Shimano have a duty to report under US law?

I’ve sent two sets of Amazon purchased SPD pedals to Shimano for warranty replacement in the past month. I’d used each set for 2-3 months when they developed bearing clicks.

That could be bad luck, or it could be Shimano has lost control of its Chinese manufacturing pipeline. I’m just too small a sample to know.

But that’s not what I’m curious about.

I’m curious about Shimano’s apparent disinterest in the Amazon reviews of the Shimano PD-A530 SPD Dual Platform Bike Pedal. Many reviewers, over several years, have described the same safety issue I ran into. These pedals have two sides, a flat side for shoes and a “cleat” (confusingly these are called “clipless pedals") side that locks onto metal tabs attached to bicycle shoes. The clip lock setting is far too tight, at the default setting it’s quite difficult to remove a shoe from the pedal. Maybe the spring is the wrong tension, maybe there’s some other design error, but this is dangerous. Reviewers report falling over in traffic due to excessively tight clips.

The workaround is to set the adjustment bolt to its minimum setting (though the bolt is more cheaply made than other SPD pedals, so you have to work it a bit to make sure the nut slides down). On every other SPD pedal I’ve worn over about 15-20 years this would be too slack, but on these pedals it’s about right. Of course a lot of cyclists won’t know to do this, or won’t immediately recognize that the pedals are miscalibrated. It’s a persistent safety defect.

Under US law both Shimano and Amazon have a duty to report safety defects...

Duty to Report to CPSC: Rights and Responsibilities of Businesses |

If you are a manufacturer, importer, distributor, and/or retailer of consumer products, you have a legal obligation to immediately report the following types of information to the CPSC:

… A defective product that could create a substantial risk of injury to consumers...

… Failure to fully and immediately report this information may lead to substantial civil or criminal penalties.  CPSC staff’s advice is "when in doubt, report.” ...


What if I receive information that reasonably suggests my product could create a safety or health hazard but no reports have been received alleging that actual harm or injury has been suffered?

You must immediately report the information about the product. The law does not require injury or harm to have occurred….

It’s clear these pedals have a defect, though a defense lawyer would argue about “substantial risk of injury”. After all, it’s the nature of clipless pedals to reduce foot-to-ground time, and a lawyer would argue that only knowledgeable people should buy a clipless pedal, and thus know how to adjust them.

It would be unwise, however, to rely on the kindness of US courts. I suspect if Shimano’s lawyers read the Amazon reviews they’d recommend doing a (confidential) CPSC report and fixing the darned pedals. Judging by the age of the reviews, however, they haven’t done the latter.

Which is interesting. Why doesn’t Shimano read Amazon reviews of its products? And what are Amazon’s obligations as a distributor or retailer?

Great questions for a law school class ...

Update 8/5/2016: Shimano sent me a replacement for the clicking PD-AF530 pedal. After less than 10 months of light use it developed a severe creak/click. Trash.

Monday, August 17, 2015

And now for something somewhat different

A somewhat wise traveler walks a path in deep desert.

He comes across a turtle that has fallen on its back. Having some wisdom he carries the turtle to its shelter. As he turns to his path a clap of sound and light announces a Djinn.

“Oh wise traveler, you have proven your worth. For you I grant a great gift. I shall open a gate to the garden of paradise. From there you can choose a flower of immortal beauty to bring you joy and peace for all your life. Come and enter …"

“Ok. Stop there. I know this one. It’s that paradox of choice schtick. I enter the garden and everything is so wonderful my brain is like, totally blown. I wander the path but, of course, I can’t go back. Only forward. Every flower is more beautiful than the last — but I can only pick one. At first my path seems unlimited, but then I see the end in sight. I start to panic. Finally, in desperation, I grab the last flower. It’s kinda nice, but I’m left a bitter wreck for all the better flowers I coulda picked. Yeah, nice try, but I wasn’t born yesterday. Get thee hence Devil!"

The Devil, for the traveller has seen correctly, smiles and tips his hat. You are indeed wise, he says. Then he blasts the not-wise-enough man to eternal hellfire. [1]

When the Devil plays, you let him win.


My job died.

Our relationship lasted between 16-20 years, depending on whether or not I count time at an acquired startup. I started out a country doc, did a health informatics degree (thank you NLM), and I became a corporate health care IT R&D guy. For lack of alternatives I was "product management", but mostly I invented and implemented tools for health care workers to use - usually for patient care, more recently for analytics and population management. My real love was making docs smarter — that’s why I went into the business. In my GP days I was frustrated by not knowing the right stuff quick enough to provide the best care to my patients.

We had our ups and downs my corporation and I. My place in that world required skills I wasn’t born to; it was a fascinating challenge to learn those and survive (many thanks to several of my managers and mentors!). The corporation had its own issues [2], so the relationship required mutual forgiveness as well as mutual need. Like most relationships. Even during not-fun times the job was good for my family.

Alas, over the past few years the business changed. Eventually there was little need for a clinical decision support expert. Even I couldn’t see a way to justify my cost — the work didn’t exist any more.

My job died, but it left me an inheritance -  some time to choose my flower. Or invent it.


When I have to invent a solution, I look for constraints. Constraints are my friends; without constraints choice explodes. I have some constraints.

Age is a big one - I can see the garden’s exit. My exercise hobby gives me back some things, but it doesn’t change time. It would be good for my family if I earned some money. My family medicine board status expires this year, so i have to make a choice there. My family is strongly rooted, for the moment, in the most excellent Twin Cities of Minnesota. I have duties to my family that are perhaps above average.

Within these constraints there are things I’d like for myself. I’d like to give something positive to the world, something that might last a few years, something that I have a meaningful part in choosing and building. I would prefer not to join another large publicly traded corporation; I’ve done that one. I have a particular interest in cognitively disabled people. I’d like to do something I haven’t done before.


I did decide to take my (last) family medicine board exams. Over the past 3 weeks I’ve completed the qualifications to write the board exam in November. That process was considerably more painful than it needed to be, but that’s not my battle to fight (age teaches something). Preparing for that exam will take me 10-20 hours a week for the next 4 months.

I have technical debt from years of juggling work and family and health to manage. I’ve had a surgery I’d delayed. I’m cleaning up finances that got cluttered over decades. Family photos and videos, home stuff — things like that. More importantly, focusing on some special needs of my children, and taking each child on a plane trip (Montreal and San Francisco down, next up - London!). Oh, and taking my 93 yo father to visit his sister in San Francisco (just keep breathing for another 3 weeks everyone). That’s taking another 10 or so hours a week.

Then there’s exercise - mountain biking, road biking, CrossFit, inline skating — most of which also serves the needs of one child or another. That’s another 10-15 hours. Household maintenance takes time, it’s been a rough month for bikes and phones and computers. Writing, because that’s how I think and pay my geek dues. Exploring new tools and techniques especially on my post-corporate MacBook Air [3]. Learning FHIR and JSON data wrangling, catching up on 5 years of JAMIA articles, and other deferred professional obligations.

That all leaves a few hours a week to figure out my next move.

I’ll probably write about it.

- fn -

[1] I remember reading the original version of this story, but Google can’t find it for me. Maybe it was another universe. Related: "Life can only be understood backwards; but it must be lived forwards."

[2] Contrary to the Supremes, corporations are not people. They have their share of quirks though; partly cuz they contain people, partly because they’re slouching towards Bethlehem.

[3] It is insanely bad luck to say that this is the most trouble-free and immediately useful device I’ve every purchased. I love buying mature Apple hardware, though I note that the iPhone 6 and new MacBook have had less quality issues than I expected. Now if Apple can only fix their software quality issues and seven years of lousy products ...


Tuesday, August 11, 2015

2015 vs. 1910 - which era has more future shock?

Remember Alvin Toffler’s Future Shock (helps to be old)?

Wikipedia, via this:

"Toffler argues that society is undergoing an enormous structural change, a revolution from an industrial society to a "super-industrial society". This change will overwhelm people, the accelerated rate of technological and social change will leave them disconnected, suffering from "shattering stress and disorientation" – future shocked. Toffler stated that the majority of social problems were symptoms of the future shock. In his discussion of the components of such shock, he also coined the term "information overload”."

Toffler was wrong about his era, and probably wrong in general. 21st century China shows humans can tolerate a vast amount of technological and social change and keep on moving on. Future Shock is more like a winter carpet zap than a lightning strike.

It can still sting though. This past week, for example, we realized landlines are finally gone — at least in Minneapolis St Paul. 

Yeah, I know. They were supposed to be dead years ago. Ahh, but that’s the trick. What I remember in 1994 is that by 2000 we were all going to have fiber to the home; voice communication would be VOIP and too cheap to meter. It didn’t work out that way. It’s easy to predict the Future, it’s hard to predict when the Future will happen.

Instead landlines seemed to slowly fade. No big changes. For various reasons we kept our home number on a landline. We didn’t notice that Saint Paul Minnesota was down to a a single provider of landline services - CenturyLink. We didn’t notice the 30% drop in CenturyLink's share price. Then one day our CenturyLink landline malfunctioned, we lost net service, and we couldn’t get it repaired. We’ve been without landline service for two weeks; a repair guy may drop in this Thursday. Maybe.

I switched our net services to the only alternative our benighted metro area has - Comcast. I forwarded the home number to our cell, and, because our security system is landline based, we wait for a repair while figuring out what to do with our identity-associated home phone number.

The line will be repaired, or not, but that won’t change the fact that for Saint Paul, Minnesota, the landline era really has ended. A wee bit of Future Shock for old folk, and a minor puzzle for our kids (who have almost no understanding of how anything connects to anything else).

Which makes me think, again, about how this era compares to the early 20th century, when horses went from vehicle to entrée, the kerosene industry collapsed, and balloons turned into airplanes. Consider the auto transition - the first mast produced automobiles were sold by Olds in 1902, by 1910 there were more automobiles than horse buggies, and by 1920 buggies were mostly gone. So a 20 year transition. Not that different from the timeline of our landline decline, but far more disruptive.

On the other hand, landlines and horse buggies are physical things. They have a lot of momentum. What about transitions in virtual things? Can the speed of transition there make our era more bewildering than, say, 1910?

On reflection, I have to say not. That automobile transition is truly incredible. We still can’t compare. Maybe when the AIs take over..

See also

Wednesday, August 05, 2015

Donald Trump is a sign of a healthy democracy. Really.

I’m a liberal of Humean descent, and I’m a fan of Donald Trump.

No, not because Trump is humiliating the GOP, though he is. Of course I enjoy seeing the GOP suffer for its (many) sins, and it would be very good for the world if the GOP loses the 2016 presidential election, but Trump won’t cause any lasting political damage. Unless he runs as a third party candidate he’ll have no real impact on the elections.

I’m a fan because Trump appears to be channeling the most important cohort in the modern world — people who are not going to complete the advanced academic track we call college. Canada has the world’s highest “college” graduation rate at 55.8%, but that number is heavily biased by programs that can resemble the senior year of American High School (in Quebec, CEGEP, like mine). If we adjust for that bias, and recognizing that nobody does better than Canada, it’s plausible, even likely, that no more than half of the population of the industrialized world is going to complete the minimum requirements for the “knowledge work” and “creative work” that dominates the modern economy.

Perhaps not coincidentally about 40-50% population of Canadians have an IQ under 100. Most of this group will struggle to complete an academic program even given the strongest work ethic, personal discipline, and external support. This number is not going to change short of widespread genetic engineering...

Screen Shot 2015 08 07 at 8 16 45 PM

This cohort, about 40% of the human race, has experienced at least 40 years of declining income and shrinking employment opportunities. We no longer employ millions of clerks to file papers, or harvest crops, or dig ditches, or fill gas tanks or even assemble cars. That work has gone, some to other countries but most to automation. Those jobs aren’t coming back.

The future for about half of all Americans, and all humans, looks grim. When Trump talks to his white audience about immigrants taking jobs and betrayal by the elite he is starting a conversation we need to have. 

It doesn’t matter that Trump is a buffoon, or that restricting immigration won’t make any difference. It matters that the conversation is starting. After all, how far do you think anyone would get telling 40% of America that there is no place for them in current order because they’re not “smart” enough?

Yeah, not very far at all.

This is how democracy deals with hard conversations. It begins with yelling and ranting and blowhards. Eventually the conversation mutates. Painful thoughts become less painful. Facts are slowly accepted. Solutions begin to emerge.

Donald Trump is good for democracy, good for America, and good for the world.

See also