Tuesday, September 25, 2007

29 yo woman with progressive scoliosis, who was told her curve would not progress as a teenager. How does scoliosis progress as an adult? What affect does pregnancy have on scoliosis?

Yesterday Jaclyn and I  saw a lovely 29 yo woman at Hey Clinic who was diagnosed with a R thoracic scoliosis as a young teenager.  The curve was followed with serial X-Rays, and by the time she turned 17 and had stopped growing, her thoracic curve was 30 degrees, and her lumbar compensatory curve was 18 or so degrees.  At that time the patient remembers being told that “she did not need to worry” since she was “done growing” and her curve was not that large.

Since then, she did just great until about 2-3 years ago, when she noticed that her “hourglass” figure was beginning to shift, with her R hip becoming more prominent, and her trunk sitting too far over to left, and abdomen becoming slightly more protruberant on that L side.  She has had some low back pain, slightly more in past year or two.

She came in to Clinic today with questions about getting pregnant and having children with her scoliosis.

Her X-Ray shown above shows that her thoracic curve was still around 30 degrees, but her lumbar curve was now approximately 39 degrees, with severe disc collapse especially at L23 level.
She was really surprised to see the degree of progression over the past 12 years.

Why did the curve below collapse?  The answer is that the asymmetric disc and facet loading over the past 12-18 years has caused an increased rate of wear of these joint surfaces.  Once the discs and facet joints begin to settle and wear out, ongoing collapse can occur, which causes a vicious cycle of asymmetric loading, leading to further collapse, and so on.  We use the analogy in clinic that the “car is out of alignment”, causing the “tires” (Disks) to wear out prematurely.  In this young lady’s case, her spine may have been quite stable for years, then at some point the disc and facet joint wear progressed to the point that rapid curve progression and posture change occurred.

Why did her “hourglass figure” change?  As the lumbar curve began to collapse, her rib cage with the upper torso “settled” down to the left side, causing the trunk to be out of alignment over the L side of the pelvis by about 3-5 cm.  This causes her L side of her “hourglass” to be lost, and look possibly like a straight line, and can cause a noticable crease in the skin between the rib cage and pelvis.  On the R side, since the trunk is shifting down and to the L, the R hip appears to be “sticking out”.  In fact, the hip is not sticking out, but the iliac crest is more prominent since the trunk above it is shifted to the L.  Her abdomen is slightly more prominent/protruberant since she has lost some height between the rib cage and pelvis, causing the abdominal contents, regardless of how many sit-ups she does, to press outward more.

Will this curve continue to progress?  Only time will tell.  However, her 20+ degrees of progression of this lower curve over less than 20 years combined with the degree of asymmetric disc collapse is worrisome.  Careful follow-up at least is very necessary.

What about pregnancy?  Pregnancy brings at least 2 major changes that could affect her comfort as well as degree of curve progression:  the added weight of the baby, combined with increased ligmentous laxity throughout the body secondary to pregnancy hormone changes.  These hormone changes help the pelvis to expand during delivery, but may cause laxity in the ligaments in the spine leading to increased incidence of curve progression.  In terms of comfort, many women have back pain during the last trimester of pregnancy.  Some women with scoliosis, especially if the curve is progressing, may have increased back and possibly leg pain  / sciatica if the added weight and flexibility leads to further collapse of disc space, and neural foraminal narrowing and/or disc bulging, slippage or herniation.  In my own practice, I have seen several women who have had rapid curve progression of either scoliosis or kyphosis of even 20 degrees or more during just one progression. Because of these possible issues, it is very important that all adult women with a history of scoliosis or possible scoliosis get thoroughly evaluated before getting pregnant with the first child, and also to be checked regularly between each pregnancy as well.  Due to the risk of radiation on the fetus, X-Rays are not recommended during pregnancy, so any suspected scoliosis would have to be evaluated with physical examination and scoliometer only.

Could this collapse have been prevented?  It is hard to say for sure, but it is possible that if the thoracic curve had been straightened and fixed when she was young, then the lumbar curve would have gone down to near zero degrees. This centering of the load may have prevented the asymmetric disc collapse in that mid-lumbar area.  This possible prevention of later lumbar and/or thoracic collapse and degeneration is one of the benefits of early fixation of scoliosis in the adolescent or young adult.

Could a brace during adolescence or adulthood have prevented this collapse?  No, unlikely.  The brace in some growing adolescents can decrease the final curve at the time of skeletal maturity, but it does not have any protective effect thereafter for any collapse later in life that could cause ongoing progression and/or quality of life problems.  Bracing typically does not improve the curve from the degree of curvature when the brace is applied — it may help to hold it closer to that number by the time they finish growing.  However, if the child/adolescent is “out of alignment” at that point, as they are taken out of the brace, they still need life-long follow-up and may have later collapse of the upper or lower or both curves during adulthood — anywhere from college age, through senior citizen years.

Could earlier scoliosis have prevented this lumbar collapse?  Probably yes.  With modern current scoliosis techniques using pedicle screw fixation, and shorter constructs for thoracic curves (T5-L1 for example), 80-95% corrections are possible of the major curve, which results in nearly complete correction of the compensatory curves on either side, including the lumbar area.   Although there can be an issue with adjacent level failure with lumbar fusions, it appears that the patients who have thoracic fusions down to L1 or L2, with most of the lumbar discs preserved actually wear their lower lumbar discs very well, especially when the top curve is well-corrected.  Perhaps in the future we will have more longitudinal studies which will show that earlier short fusions can prevent the later collapse of the upper and / or lower curves that tend to affect quality of life a lot in the adult population.  In this case, a “stitch in time may save nine”, in that a smaller operation can be performed on the adolescent or young adult which prevents the need for a longer instrumentation and fusion later in life to fuse across both the upper and lower curves. This younger age may also allow for a greater degree of correction, with subsequent improvement in load balance, and by fixing it at a younger age allow the discs to be subjected to more centered loads for the duration of the life of the person.

What about Self-Image and Appearance and Posture issues: are they fixable?  Bracing in some adolescents can “slow” the curve progression during the growing period so the rib hump and lower hump may be smaller, but it will not make the humps go away.  Bracing as an adult can sometimes help the back pain that can occur especially in the older adult with low back pain, but does not stop curve progression or self-image in most cases.

In this 29 yo patient’s situation, she is actually going to get her old X-Rays, and get a lumbar MRI so we can further evaluate the rate of progression, and also the degree of lumbar stenosis and degeneration that has already occurred.
She is considering having her scoliosis fixed prior to having her first child, since she is already concerned about the evident progression as an adult, her change in posture and self-image, and the concern about ongoing progression and degeneration which may affect her quality of life during her pregnancies and future life.

One of the interesting things about Hey Clinic is we take care people with scoliosis across the whole age range, from little children up through adolescents, young adults, middle-aged adults, and older adults.  Working with this “full spectrum” of patients gives you a different perspective than just treating children alone, since the “finish line” for successful treatment for a child or adolescent is skeletal maturity with a curve less than 40 degrees for scoliosis.  However, the real “finish line” for life is actually 70+ years down the line for most people, and there are many ways in which scoliosis and kyphosis can impact on quality of life during those years.  As we talked about in the last Blog, there is clearly a need for further outcomes studies in scoliosis treatment, where we really try to get a handle on outcomes that really are more meaningful to patients and their families, rather than just a successful short-term radiographic measurement.  

Lloyd A. Hey, MD MS
Hey Clinic for Scoliosis and Spine Surgery
Raleigh, NC -- USA

1 comment:

skye said...

my sister is 23 had two metal rods put in at 16 had futher sugery at 17 to remove a small section of one of the rods, despite the operation her curves have continued to grow and her hips are getting futher out of allingment also on odd occasions her leg collapses, she just found out she is pregnant what are some of the risks??