Blog Topic: Recent Publication in The
Spine Journal
6-14-2022
Scott Luhmann, MD, the author of this blog, is a pediatric orthopedic surgeon at Washington University Orthopedics in St. Louis specializing in pediatric and adolescent spine surgery. He practices at St. Louis Children’s Hospital and Shriners Hospitals for Children in St. Louis, Missouri. Your comments and feedback are encouraged.
Blog Topic: Congenital Spine
Dislocation with 8 Years of Postoperative Follow-up
6-8-2022
Congenital dislocation of the spine (CDS) is a rare congenital
malformation due to failure of the spine and the spinal cord to develop at a
single spinal level.
The patient may be completely neurologically intact or, in
severe cases, may not have any muscle function or sensation below the level of
the dislocation.
It is potentially the most serious form of congenital kyphosis or scoliosis with an abrupt single-level displacement of the spinal canal. See the below x-rays of an 18 month old female, who was noticed to have a “bump” on her back, at the red arrow.
She was moving her legs normally and was felt to have normal
sensation in her legs. The red arrow
points to the T12 vertebra which does not sit under the T11 vertebra (orange
arrow).
The right side X-ray shows how the upper spine (thick green
line) does not line up with the lower spine (thick red line)
When lying down the T12 vertebra does not move under the T11
vertebra…..it is dislocated.
On the below CT scan cuts the red arrows point to the dislocation, with T12 sitting too far back.
To correct the dislocation, the T12 vertebra needed to be
completely removed, and once it was the spine was very mobile and allows T11
get appropriately lined up with the L1 vertebra. Because there was a space between T11 and L1
a cage (yellow arrows) was put between them to add to stability and put the
spinal cord at the correct length.
Four pedicle screws were placed above and below the removed T12 vertebra and were locked down. To make sure this area heals solidly, and permanently a bone graft was placed in the cage in the front and also in the back of the spine.
In the below slide the patient is now 6 weeks after surgery. It is easy to see the improvement of the spine alignment back to normal. Because the bone is soft at this age we kept her in a brace for 6 months to protect the surgery.
Here she is now 8 year out after surgery. She has normal spinal alignment and normal function of her spinal cord. Her long-term prognosis is for a normal life.
Blog Topic: Disc herniation/Bulges in adolescents and how to treat
5-3-2022
So, the symptoms of lumbar disc problems and the cause
symptoms (pressure against nerve roots) are similar between adults and
adolescents.
What is different?
In adults the pressure is created
by a dehydrated (lack of water) or a bad disc herniates through the posterior
ligament in adults
In adolescents the growth plate on
the vertebral body (called ring apophysis) fractures and pushes backwards.
So what are the
available treatments for adolescents? There are two main groups:
·
Nonoperative
o
Rest (short-term only)
o
Analgesics (pain medications)
o
Physiotherapy: Paraspinal and Core
strengthening, aerobic conditioning
o
Spinal injections: epidural and selective nerve
root
o
What do I not recommend:
§
Chiropractic manipulation
§
Bracing (weakens back and core muscles)
·
Operative/Surgical:
Microdiscectomy
Some important
facts:
+ Nonoperative treatment listed above is almost ALWAYS the
first step in care. This is because most
ring apophyseal injuries are minor, heal and don’t cause long-term problems.
+ Persistent numbness and weakness require more urgent
treatment and more frequently need early surgery.
+ There is no hurry to do surgery (from a surgeon
standpoint) when there is only pain down the leg +/- back pain. Surgery appears to be helpful in relieving
leg pain even if done late.
+ Selective nerve root injections can be diagnostic and
therapeutic. Even temporary symptom
improvement is important as it can help identify the cause of the back/leg
pain.
+ Microdiscectomies do a good job of improving leg pain, but
not a good job of alleviating back pain.
When should I
consider an Operative/Surgical Microdiscectomy?
If nonoperative treatments have failed to adequately
alleviate leg pain
There is a ring apophseal fracture or disc herniation on MRI
Selective Nerve Root Injections confirm pain generator, even
if only temporary relief
Discussions with your surgeon determine the pain generator
is the disc and no other nonoperative options remain which could help.
Blog Topic: Disc herniation/Bulges in
adolescents, and how they differ than those in adults.
4-7-2022
When talking about a new topic, I have tended to go into
significant detail about the basics of the problem to be discussed. However, after review of the below webpage
from the American Academy of Orthopaedic Surgeons (AAOS) I don’t think I can do
a better, more thorough explanation of the anatomy, pathology, diagnosis and
treatment of disc herniations in adults.
Therefore, I will encourage you to use this hyperlink:
https://orthoinfo.aaos.org/en/diseases--conditions/herniated-disk-in-the-lower-back/
Alternatively, try this link to
OrthoBullets:
https://www.orthobullets.com/spine/2035/lumbar-disc-herniation
Like many problems in the musculoskeletal system, there can
be significant differences between adolescents and adults, from presentation,
to diagnosis, treatment and the short- and long-term outcomes. Therefore, before we discuss the differences let
us present some of the commonalities between adolescents and adults:
So what are the differences between adolescents and adults?
In Adolescents:
In the below diagram of the spine the normal ring apophysis (at green arrow) is
a growth center in the developing spine and is a weak link when twisting and
bending forces are placed onto the spine.
If overloaded, the ring fracture is pulled off the vertebra (black
arrow) and moves toward the spinal canal (the area in blue).
In Adults: When
the nerve root exits the spinal canal (green arrow) there is plenty of room
without any areas of compression. When the
disc degenerates it will push a piece of the disc into the spinal canal and
against the nerve root (red arrows) which can cause leg pain and numbness and
muscle weakness in the leg.
Blog Topic: Bone Grafting in Spine Surgery
3-12-2022
In the previous blog post, we presented “what is a spine
fusion”?
In most pediatric spine surgeries metal implants correct and
stabilize the spine in a new position (see below), then a spine fusion is
performed.
What I tell families/patients: “The metal allows us to
attain and maintain the spine in a new position while the spine then creates a
bony fusion”
How do you get a spine to fuse? During surgery, after the
implants are placed and the spine is corrected (see above), the fusion part of
the surgery is then done. This involves decorticating, or roughening up, the
bone in the back of the spine. This stimulates
the bone to heal, and the bone graft then is laid over this roughened
bone. The body breaks down, or digests
this new bone graft and then creates a solid bony connection.
In the past, we used to always use the patients’ own bone,
usually taken from the iliac crests above the hip joints. This type of bone is
call “Auto-graft” = the patient’s own bone, whether it be from the spine,
pelvis or both.
Harvesting the iliac crest bone takes additional time in the
OR and it really hurts after surgery.
Since we have switched to allograft the amount of postoperative
narcotics needed and the length of time patients’ were having significant pain
has declined.
The standard of care now in pediatric spine surgery is to
use allograft bone. “Allo-graft” =
another person’s bone.
Bone is not rejected from the person receiving it, unlike in
other type of tissue transfers between people.
There are no antigens on bone, unlike other transplanted tissue such as hearts
or livers.
At present, during spine surgery there is some small amount of
the autograft, or the patient’s own bone, which is collected during surgery,
but the majority of the bone used is allograft.
So both types are used in deformity surgery, but most of the volume is
because of allograft.
Appointments: 314-514-3500 Appointments: 314-432-3600
Blog Topic: Latest Publication on Intraoperative
Halo-femoral Traction
1-26-2022
This study was just
published in the Journal of Spine Deformity
For those
interested to read more please use this hyperlink supplied by the publisher:
https://rdcu.be/cFHmd
Blog Topic: What is a “Spine Fusion”
1-16-2022
In the average, normal spine there are 7 cervical, 12
thoracic, and 5 lumbar vertebra, a sacrum and coccyx.
From the skull to the sacrum, each vertebra is separated by a mobile disc, which is a highly complex structure which provides stability and motion at the same time.
In spinal deformity, such as scoliosis, the spine twists and
bends, first through the discs and then the actual vertebra start to become
misshapen, more trapezoidal instead of being more rectangular.
When we do surgery to correct spinal deformity (scoliosis)
the first step is to get fixation into the vertebra so we can move those
vertebra to a better, more desired position and then hold this new position
firmly. In 2022 the most secure and most
commonly utilized spine fixation are metal pedicle screws (usually made of
titanium +/- cobalt chrome), which are placed from the back of the spine, into
the bone, through the pedicle and into the vertebra.
Alternatively, hooks, wires and bands can also be used but these
are not as good a fixation option when compared to screws.
The next step is to connect these screws (or hooks, wires,
and bands) together with rods. These
rods can then move the screws (or hooks, wires, and bands) to the desired position
and then held rigidly in the new position.
These rods, in my practice, are 98% of the time are cobalt chrome, the
stiffest metal currently available and can obtain the optimal 3-d alignment of
the spine in my hands.
These metal screws and rods are VERY strong and
durable. However, we know the day we
place them in surgery is when they are their strongest and have the strongest
grip/fixation on the spine, and each day that goes by after surgery the metal
gradually and almost imperceptibly gets weaker and the screws/hooks/wires/bands
can get looser in/on the bone.
So 1 of 3 outcomes happen after we do spine surgery, at EACH
VERTEBRAL LEVEL:
1. 1. The screws, hooks, wires, bands get loose from
the bone.
2. 2. The rods, screws, hooks, wires and bands break.
3. 3. The spine fuses.
To achieve a spine fusion, we roughen the area to be fused with a drill, and then place bone graft. The body then breaks down/dissolves the bone graft which is then used by bone cells to create a solid bony connection over the area we want to fuse.
The aim of bone graft is to develop a spine fusion before
the spine implants get loose from the bone or break.
Next blog post will discuss the different type of bone
grafts.