Blog Topic: Recent Publication in The Spine Journal

6-14-2022

 

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.

The below MRI cut nicely shows how the spinal cord is draped over the posterior T12 vertebra.  It is easy to see if the dislocation gets worse the spinal cord will get more compressed and deformed, which would then cause problems with muscle function and sensation in the legs and cause bowel and bladder incontinence (inability to control).

 

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:

• ·        Symptoms of low back pain, leg/hip numbness and pain and leg muscle weakness are similar. 
• ·        Nerve root pain is caused by the disc material compressing the nerve root.
• ·        Both typically have a more acute onset of back and leg pain symptoms, often related to a twisting/bending motion.

 

So what are the differences between adolescents and adults?

• ·        “Arthritis” is common in adults and uncommon in adolescents. 
• ·        Disc degeneration is required for a disc herniation in adults and often there are multiple levels which have degenerative discs.  “Only bad discs herniate”.
• ·        In adolescents, disc degeneration sometimes is seen on MRI. 
• ·        In adults, a piece of the degenerated disc is extruded backwards against the nerve roots (see below diagram).  In adolescents the small growth plate on the vertebra separates and this piece of bone and the attached soft tissues move backwards against the nerve roots (see below diagram).

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.