So as it is my winter break (and a new year), and i don’t have any immediate work, i’ve been occupying myself with simple resolutions. Drink more water, sleep more, eat things that are better for me and exercise more. So far the former three I’m doing pretty well with, if I do say so myself. Now if I could just stop lounging around. On the bright side, some of my lounging is inevitable since I am also applying to jobs/internships/research. I probably mentioned before, but I want to take a year or two off before I decide to go into a graduate program. So in the meantime I’ve been looking at opportunities varying from NIH related positions, to research (in Zurich because I want to leave the country :P) and other interesting job openings that come my way, like working for a Nature Conservation organization, if I get it. Now I just have to remember which ones I applied for, and to follow up in a few weeks if I haven’t heard anything.
amended: i also applied for an intern position at NIH and am trying to finish the QuEST application
RAWR! another late night post because i simply must just get these things out of my head.
so what exactly is firing around in my neurons these days, you ask. well the internal debate between whether or not i will go in the clinic or more research-y path is still at a stalemate. i recently got a gander of some of the research being done at Harvard (http://www.fas.harvard.edu/~skeleton/) and became extremely fascinated. but i’m still enjoying working in physical therapy settings.
next semester i am taking a seminar on biomechanics and will have research to do with the second half of that. i will also be doing research with one other student under a professor looking at symmetry in various organisms to understand their potentially adaptive nature. and on the side i will still be working at IPT and probably will start volunteering at a hospital nearby on the weekends.
future more immediate plans- i’m applying for a job at a hospital near my home trying to work under a physical medicine and rehabilitation unit. i’ll let you know on the progress with that in the near future.
after that… i’m trying to see if i can combine a year of volunteering under a quaker association with a nonprofit organization for children with special needs and start creating a knowledge of i guess what would be touching occupational therapy ideas. or/and look into doing some kind of research for that year.
okay now that i’ve got that all of my chest i’m going to try to grab some ZZZs before class. -.-
a smorgasbord of updates on my directed reading as well as some more IPT stories and a special entry on a guest speaker my school hosted recently will be up in the near near future. after all, classes are soooo close to being done. :D
ugh i fail at consistency. i promise to update the other weeks of my directed reading eventually.
in the meantime, more job stories. so i’ve gotten a lot better at running through charts with patients and not having to ask the physical therapists what exercises are every few minutes. it’s nice to feel like i can be depended on rather than needing to be supported and watched over every second.
anywho, some highlights from my adventures at PT…
1) meeting my boss’ children (5 of them) the week of halloween and just asking them all manner of questions i could think of including what they want to be when they grow up (the youngest answered a professional test taker) and various other random things to pass the time.
2) a pen leaking all over my hands and the PT looking at me and exclaiming “hold on, your face!” and me realizing i must have gotten pen all over myself and saying to the 17 year old male patient “i’m doing no shave november” before going to wash my face off.
3) meeting two adult patients that knew one another (one was the teacher of the other) and having a blast laughing with them while they did their exercises (especially cat/camel) and gossiping about our lives.
4) the day there were these delicious brownies and i was starving
5) when a bunch of patients cancelled and we had free time so i got to work out and use the pilates machine (my goodness how i love that machine. it is definitely on my future christmas list for when i have a permanent residence).
~ week 4 ~
yes i realize it’s not thursday- i’m still a bit behind. anyway, this the topic was all about ACL reconstructions.
1 - the biomechanics of anterior cruciate ligament rehabilitation and reconstruction (arms et al)
this article is a bit on the dated side (1984) and it shows at times in terms of mentioning things like “the rehabilitation of ACLs remains enigmatic” when in actuality we’ve got a lot of proof in the 40ish years that have passed. but besides that point, it was quite accurate in its results about strain and whatnot for reconstructed ACL.
the study entailed using cadavers, and looking at reconstructed ACLS of one leg and lateral knee as well. the ACLs were sewn in using sutures, which also showed that too much tension could tear the sutures (but given that the study was using cadavers, not healing humans, that incident number would be higher). investigating passively flexed positions as well as eccentric loads of the quadriceps and determine the impact. some key results they mention are that when the leg is passive, from 0-45 degrees flexion there is less strain than 45-above, whereas when quad contraction is involved, the opposite is true.
they also talk about how varus and valgus (bowlegged-ness and knock-kneed-ness) also create more strain.
they studied the effects of strain with and without the anteriomedial capsule, the results being that without it, strain is much greater.
they also looked at how external and internal rotation of the tibia increases strain.
my professor and i questioned whether or not the capsule is repaired during surgery or if it repairs itself.
important tests to note (in that some may appear frequently in other articles) on testing ACLs:
~ Lachman test: http://www.youtube.com/watch?v=gfN-p-xZx24
~ anterior drawer test: http://www.youtube.com/watch?v=yQdBrr3Mmj0
other interesting things the article pointed up that haven’t been mentioned before: they talked about the potential problems of using a tendon in place of a ligament, in that tendons are used to more linear tensions. they also mentioned that an incorrectly placed ACL would result in more strain.
overall the paper supported that an ACL reconstructed knee can withstand the same loads as a normal ACL
2 - extensor mechanism function after patellar tendon graft harvest for anterior cruciate ligament (rosenberg et al)
this paper was interesting because it pertained more to my life. it looked at 10 patients whom all had ACL autographs using their patellar tendons and the study investigated consequences of using such a graft in the long run. in short, although the graft is frequently used because of it’s bone-to-bone fixation and its overall strength, the people who get this type of surgery often have palpable defects of their patellar tendon afterwards that can be visibly seen with CT and using MRI. also they often will have problems kneeling, sitting, stair climbing and doing other extensor mechanism related activities. there also is generally quadricep deficiency resulting after this surgery and knee scar formation.
this study also included patients that had had iliotibial band tendosis (which can be read about in this paper, but be warned, the pictures are graphic: http://www.pjsr.org/Currentissue-PDF/Dr.%20Rajat%20Saran.pdf)
3 - gait analysis post anterior cruciate ligament reconstruction: knee osteoarthritis perspective (hall et al)
here we have a study that compared the ACL reconstructed leg with the uninjured lateral one and then had a control of completely non-knee injured people.
the results: people with ACL reconstructed legs will have reduced initial knee flexion angles when descending down stairs as well as reduced knee extension moments while doing any kind of stair activity. in compensation they tend to use their hips and so they’ll have increased hip extension moments especially during ascension. it is likely that because of these factors, their likelihood of getting osteoarthritis increases. and knee varus moments increase OA by a factor of 6 for every 1% varus moment increase.
some things to point out:
~ the graft types in this study varied (hamstring, patellar, hamstring and cadaver, and cadaver alone). the type of cadaver tissue was not mentioned
~ the types of shoes that the participants was based on their preference- which is important to note given that we read all about the effects of heels and there are also effects of wearing shoes like flipflops versus sneakers
much of the study was based on presenting various data from exercises with various variables and so my professor and i had a difficult time coming up with an overarching summation of the facts, besides what was aforementioned.
optional - anterior cruciate ligament reconstruction (meisterling et al)
we looked at this paper briefly more for a modern sense of what is going on with ACL reconstructions. this paper talks about the many details one must pay attention to before the surgery during the diagnostic phase, during the surgery and after.
~ week 3 ~
this week is all about my particular injury area bias - the ACL. i’m going to stave away from putting up pictures this week because the experiments involved a lot of cadavers and in the one article, getting down to the bare minimum necessary to test what they wanted.
1- biomechanics of anterior cruciate ligament failure: an analysis of strain-rate sensitivity and mechanisms of failure in primates (noyes et al)
this first article was interesting in that they took Rhesus monkey knees (the animals were killed before) and essentially dissected them down to just the ACL, the tibia and the femur and then applied load (both at slow and fast rates alternatively between the two knees of each monkey) in the form of tension until some kind of separate happened. the results of separation were mostly ligament tears when the rate of deformation (strain) was fast, and mostly tibial avulsion (pulling) fractures when the rate was slow. another interesting tidbit is that at the faster rate of deformation, the ACL was able to absorb more energy before it torn, than at the slower rate.
they suggested examples that might result in tensile force such as hyperextension, abduction, and forward displacement.
- what would cause slow deformation in humans?
- why the bone avulsion fractures occur so easily. conceptually one would think bones would be able to resist shattering when exposed to tensile forces
- can this experiment, given that the ACL is so exposed since they removed virtually everything else, really be applied to other situations given that much of what they removed would serve as some sort of other support for the knee. was the removal of other parts to allow for easier access to the ACL to measure strain?
- what would an experiment of this type be like today? this article was published 1973, so would much of the methodology present in it be dated, and their conclusions proved less valid now that new technology is available?
applicability to humans: the only real takeaway is that ACLs can absorb more energy before failure when the force (if tensile) is applied faster. other than that, the other results are hard to interpret for a modern day human
2 - strain within the anterior cruciate ligament during hamstring and quadriceps activity (renstrom et al)
this article was about a decade more recent than the monkey one, and did the study, or so i thought, mostly to provide information for appropriate post-ACL reconstruction rehabilitation techniques. the testing done involved human cadaver legs, but mostly the upper leg part down to some of the tibia. they hooked up the quads and hammies to machine to stimulate contractions and then tested the strain put on the ACL when the quads were contracted alone, then the hammies alone, then both together. their findings indicated that hammies alone are not harmful to ACLs but quads are very much so straining to ACLS when knee flexion is 45 degrees and below. hammies and quads together, the study said, were still strenuous, in that the hamstring could not compensate for the quad contraction strain but on the ACL, but the data supporting this statement seemed to contradict it somewhat.
some things we questioned/wondered about:
- the experiment was done by cutting the tibia to uniform lengths for the specimens, and then adding weight to simulate lower leg weight… why not just use the weight of the lower leg, especially if the legs will vary by specimen and then just account for those differences when calculating strain later on?
- would the fact that they used cadavers have an impact on the the results, possibly because of degradation of tissue, lack of blood flow, etc might affect how quickly/strongly contractions of the muscles can move
- their baseline for the motions was described as passive normal and was the cadaver limbs being moved around without stimulated contractions and that being tested. wouldn’t the baseline of a living human differ greatly here?
the take away from this article would probably be to those undergoing rehab, that working on isolating hamstring workouts, even right after surgery, are not dangerous to the new/healing ACL, yet quadriceps exercises should be avoided. also this supports last week’s article of the quadriceps antagonist role on the ACL when flexion of the knee is 45 or less.