Tuesday, July 27, 2021


Blog Post: Spondylolysis/Pars Fracture                                                7-27-2021

Part 5: Surgical Treatment

If the nonsurgical treatment discussed over the last 2 posts fails to adequately relieve the low back pain due to spondylolysis/pars fractures, then surgery might be indicated. 

It is important to note that not all patients have the same pain intensity, frequency or interference with activities.  The radiographs of the spondylolysis/pars fracture may look identical between to patients, but their pain may be very different, one having little pain, while the other significant pain.

The goal of surgery is to get the crack in the bone to heal, which should significantly decrease or eliminate the low back pain.  Just like in other areas of the body in which the bone doesn’t heal, there are specific requirements to successful spondylolysis/pars fracture surgery

What is needed to heal the spondylolysis/pars defect:

1.                      Rigid fixation/stabilization of the unhealed area

2.                      Hold the cracked, bone edges firmly against each other

3.                     Remove soft tissue at cracked bone area and takedown of the unhealed area to healthy, bleeding,                     cancellous bone

4.                      Bone graft

Figure (Pountos)



What is the surgery to “fix” spondylolysis/pars fractures?


The surgical incision to fix the spondylolysis/pars fracture is demonstated below (red line)

The intraoperative picture below.  The incision is made (between the red arrows), then the muscles are moved to the left and right sides (yellow arrows).


Dissection is continued down to bone and the spondylolysis/pars fracture is exposed, cleaned of soft tissue then burred down to healthy, bleeding bone (between green arrows, below)



Below, a pedicle screw is placed through a percutaneous incision (black circle/red center) 


The pedicle screw (black circle, red center) is connected to a hook (yellow arrow) by a rod, and then are compressed together to put the cracked bone surfaces together firmly.


Bone graft is then spread over the bone surfaces to encourage bone-to-bone healing (outlined in blue) 


Below are radiographs, before and after, spondylolysis/pars fracture repair. 



Pountos I, Georgouli T, Pneumaticos S, Giannoudis PV.  Fracture non-union: Can biomarkers predict outcome? Injury 2013;44:1725-1732.

More on Spondylolysis/Pars Fracture surgery in next post......


Saturday, July 24, 2021


Blog Post: Spondylolysis/Pars Fracture                                                7-24-2021

Part 4: Surgical Treatment


Frequently-Asked Questions:

When should surgery be performed for spondylolysis/pars fractures?  There is no one answer for everyone, as every situation is unique.  Since nonsurgical management (mentioned in last blog post) may effective in minimizing or eliminating pain, it is necessary to see if this method is successful before undergoing surgery.

If I have been doing nonsurgical management, and still have pain, how long should I continue nonsurgical management? We try a minimum of 3 months of nonsurgical management (physiotherapy, pain medications, activity limitation and possible bracing).

If I have had pain for years, should I do nonsurgical management? In situations with longstanding pain, a surgical repair may be the best option. There is a low chance nonsurgical management will be effective.

If I have done nonsurgical management and my pain is better, should I have surgery? No.  Surgery should only be done if there is pain which is not acceptable. If surgery is not necessary and the spondylolysis occurs in a younger patient, <12 years of age it is important to get intermittent radiographs of the low back to watch for any potential slippage (spondylolisthesis) of the vertebra forward. We will discuss spondylolisthesis in future posts.

How will I know when I should have surgery? When pain is interfering with activities that you enjoy, nonsurgical management has failed to adequately relieve the low back pain, and you are frustrated with the persistence of symptoms despite appropriate nonsurgical treatment.

What are the surgical options? The surgical repair is aimed to simply getting the crack in the vertebra to heal, without a fusion between vertebra, so no back motion will be lost.


In the next post we will discuss surgery for spondylolysis/pars fractures.


Monday, July 19, 2021


Blog Post: Spondylolysis/Pars Fracture                                                7-19-2021

Part 3: Nonsurgical Treatment


So far we have described the anatomy of the vertebra, the location of a pars fracture/spondylolysis, how it develops, and how we can diagnose it. Now we will discuss how to treat a pars fracture/spondylolysis.

As mentioned in an earlier post the main symptom is low back pain, which typically increases with sporting/athletic activities, and may also interfere with activities of daily living (i.e. attending school, sitting, etc…). So, a major part of treatment is to minimize or eliminate low back pain. 


How do we treat the low back pain from a pars fracture/spondylolysis?

1.      Limitation of activities: This means the avoiding activities (as much as possible) which make the back pain worse, such as sports/athletic activities.

2.      Pain medications: In general, medications for pain control should be limited to over-the-counter acetaminophen.  Infrequently have we employed the use of a Pain Service, an anesthesiology-driven service who have expertise in pain medication, for individuals with more severe pain which interferes with activities of daily living.

3.      Physiotherapy: Strengthening of the paraspinal back muscles and core musculature can be helpful in decreasing low back pain.


4.      Bracing: use a rigid flexion lumbosacral orthosis (LSO) may be beneficial, especially when the pars fracture/spondylolysis is relatively new.  If prescribed it is usually worn for 3 months.  Flexible low back braces have been advocated, with some literature support, however they are rarely recommended for patients seen in our clinic.

Will the pars fracture/spondylolysis heal with bone? Acute pars fractures/spondylolysis may heal with bone.  However, we don’t know if bony healing is necessary for pain relief.  All that may be needed is a fibrous connection or scar tissue to fill the area and make it stable enough to mitigate the pain.  So, rather than worrying about bony healing, the definition of success is the elimination of pain.


How long can nonsurgical treatment be continued?  There really is no limit to how long one can limit activities, use acetaminophen, and perform low back strengthening.  The amount of pain and how it interferes with activities is unique for each individual. 


When should nonsurgical treatment be stopped and surgery should be performed?  Since the amount of low back pain varies significantly it really depends on each individual’s perspective.  How does the pain interfere with activities of daily living? Or sports/athletic activities?  How frustrated is the individual in their inability to do the activities they enjoy?  These are all questions which need to be answered by individuals with pars fractures/spondylolysis

It is relatively common the surgery is not wanted by individuals/parents when they are in 8th-11th grades.  This is because if they choose to do surgery the individual will be out of sports/athletic activities for 6 months after surgery.  This can significantly disrupt different sports seasons.


We will continue to present this topic over the next several posts, with the next post discussing surgical treatments.

 Blog Post: Spondylolysis or Pars Fracture 7-18-2021

To summarize the previous post, the pars interarticularis likely never developed normally for individuals who get a spondylolysis or pars fracture.  With continued stress on this area during normal and athletic activities the abnormally-developed pars cannot handle the repetitive stresses applied and a crack develops.

If the pars is bone, why doesn’t it just heal like other fractures in the body?  As demonstrated in the previous post the area of the pars is rather narrow, and the bone at the pars is mainly comprised of cortical bone (slow healing ability) rather than cancellous bone (fast healing ability).  So, unlike other bones of the body which have a lot of cancellous or spongy bone, which heals faster, the pars has more cortical or dense bone, which heals slower.  Normally our bone gets stronger as we apply stress to it, during our physical activities, as long as it is in a gradual fashion and the bone has time for it to recover from the stress and make new, stronger bone.  However, if the bone is repetitively over-stressed, faster than it can heal, a crack or fracture can occur.  We also see this in other areas of the body, such as the tibia or the foot in runners, and we call them “stress fractures”.


What symptoms are associated with a pars fracture/spondylolysis? Like a fracture in other areas of the body the main symptom is localized pain at the fracture site.  Pain is typically worse with more strenuous activities, such as sports, and improves with rest.  Other symptoms can also be present, such as pain which radiates to the buttocks and back of the thighs, which also gets worse with activities.  Paralysis/weakness of the lower extremities and bowel/bladder dysfunction do not occur from an isolated spondylolysis.


What is the first step in diagnosing a pars fracture/spondylolysis? The first step is a simple two view radiographic series in the AP and lateral projections.  Additional oblique views can be helpful.

The below radiographs are of a 14 year old female with 18 months of low back pain


It is not easy to see but at the tip of the red arrow there is decreased bone density, which is indicative of a pars fracture/spondylolysis, but is not definitive.

                 Right Oblique Left Oblique


The above two oblique radiographs demonstrate bilateral (both sides) pars fractures or spondylolysis. 

The below oblique demonstrates the “Scotty Dog” of the posterior elements of the spine.  The pars fracture or spondylolysis looks like the dog is wearing a collar.


Can a pars fracture/spondylolysis always been seen on plain radiographs? The simple answer is: no.  If the symptoms are for less than 2 months the plain radiographs may be negative.  Sometimes more advanced imaging is necessary, such as CT scans, MR imaging or bone scans.

Below is a CT scan demonstrating bilateral pars fractures/spondylolysis (black arrows) at L5

         Axial image       Left pars          Right pars

Next post will discuss treatment options for pars fractures/spondylolysis.

Saturday, July 10, 2021


Blog Post: Spondylolysis or Pars Fracture                            6-26-2021


Before we talk about what is Spondylolysis or Pars Fracture, we need to understand what is normal.

So, what is normal vertebral anatomy?

As you below in the two drawings the vertebra of 3 parts: the vertebral body (which is in the front), the posterior elements (in the back; red circles), and the pedicles (which connect the vertebral bodies in the front to the posterior elements in the back.


The spinal cord and nerve roots run in the blue areas below:


Notice the 3 parts of the vertebra create a full bony ring around the spinal cord and nerve roots (below):



What is a pars fracture/spondylolysis? A pars fracture/spondylolysis (red lines, below) is a break in this bony ring at the area called the pars interarticularis.

This means the back area is not attached, is loose and can wiggle back and forth with back motion.


What does spondylolysis mean? If you break down the word into its Latin roots, spondylo- means “vertebra” and –lysis means “break”.  So the red lines are the place where the break in in the posterior elements.

Is there a difference between pars fracture and spondylolysis? No, they mean the same thing.  I believe the main the phrase “pars fracture” is more commonly utilized is due to the difficulty in pronouncing “spondylolysis”, and its similarity of “spondylolysis” to the phrase “spondylolisthesis”, which is a more advanced/severe stage.

Can you be born with spondylolysis? There have been no reports of spondylolysis being present at birth, so they develop over time.

Why does it happen? Most likely all those pars that break did not develop normally. The pars area is very narrow and with motion gets stressed, then a crack develops.  If this problem was simply due to sports or a particular activity, we would see this much more commonly.



The area then cracks…


We will continue to present this topic over the next several posts.