Pain With Back Extension Should Trigger A Pars Workup

A 17-year-old volleyball player walks into clinic with a week of non-traumatic low back pain, but her story has a detail I never ignore: months earlier, she felt a “pop” during a jump and her symptoms worsened with trunk extension. That combination of athlete profile, mechanism, and exam findings should immediately put pars interarticularis stress injury on your radar. I break down exactly what I saw on exam, why extension pain is such an important clue, and how this presentation can mimic a simple muscle strain while actually being spondylolysis in progress.

From there, we move into imaging and diagnosis in a way that is practical for real-world orthopedics and sports medicine. I walk through the lumbar x-rays, the limits of plain films for early stress reactions, and why MRI is often the preferred next step in adolescents to identify bone marrow edema and unilateral pars involvement without radiation. We also define the terms clearly: spondylolysis as a pars fracture and spondylolisthesis as a forward slip, plus what symptoms and red flags to listen for when an athlete reports buttock or upper hamstring pain.

Finally, we build a management plan you can actually use. I cover conservative treatment options including activity modification, the pros and cons of bracing, physical therapy priorities like core strength and hip mobility, and return to play criteria that focus on being fully pain-free with normal strength and sport-specific tolerance. We also touch on surgical indications, what direct pars repair can look like, and prevention strategies that start with training volume, flexibility, and avoiding year-round overuse. If you found this helpful, subscribe, share it with a clinician or coach who works with young athletes, and leave a review with your top takeaway.

Transcript

Welcome And Podcast Focus

SPEAKER_00 0:07

Welcome to the Ortho on the Go podcast. My name is Chuck Dowell, host of the podcast. This is an educational orthopedic podcast focused on discussing both clinical and functional orthopedics. We will discuss a variety of topics within the field of orthopedics, including reviewing interesting cases, hearing from different professionals throughout the orthopedic profession, and discussing common musculoskeletal injuries and complaints. This podcast is meant for anyone that wants a better understanding of orthopedics, including all levels of practitioners, coaches, parents, and athletes themselves. Hello, everyone, and welcome back to the podcast. My name is Chuck Dowell. I'll be the host for today's episode.

Teen Volleyball Player Case

SPEAKER_00 0:47

Today we're going to do another case presentation. This is a patient that I saw in clinic recently. This is a 17-year-old female who presented to the clinic with one week of non-traumatic uh lower back pain. She states the pain was worse when moving. She had a throbbing pain at baseline. She states approximately six months prior, she had had a similar episode of lower back pain that took roughly six months to get better, but did get better where she was able to participate back into sports. She primarily is a volleyball player. She states originally the injury happened back six months prior when she was in a volleyball game. She jumped, she felt a pop, some weakness, some pain in the lower back and upper hamstring area. Again, she treated this conservatively. It gradually got better, but then subsequently got progressively worse. She came back to the orthopaedic clinic to see me. On physical examination, she had mild diffuse tenderness within the lower back area, primarily the perispinal area, L3 through S1. Some tenderness was noted directly over the spinous process of L4 and L5. She had noticeable increasing pain with any type of truncal extension activity. Improved symptoms was noted with trunchal flexion and rotational activities.

X-Ray And MRI Walkthrough

SPEAKER_00 2:05

So you can see her x-rays on the screen right now. These are the x-rays we took. We took an AP and lateral view of the lumbar spine. It's hard to tell, but you can see, and again, if you're following along on the YouTube channel, you should be able to see these x-rays and the videos associated with this presentation today. My cursor will show you you can see a little small defect in the PARS here at the L5 level. This makes sense based upon the patient's symptoms. She had noticeable increasing pain with any type of uh trunchal extension activity, which usually causes this type of pain. Subsequently, because this was a repeat episode, she'd had it six months prior and it took six months to improve. We obtained an MRI. Again, you can see on the screen now, I'll push play and we'll kind of roll through the MRI itself. And you can see primarily on one side as we're rolling through here, no disc herniation's good space, but right here there's increased fluid uptake within that parse area on that unilateral side. And if we can kind of roll back here a little bit, again, you can see right there, there's a good view of that increased uptake in that area.

Pars Injury Basics And Symptoms

SPEAKER_00 3:31

So I think when we define parse fractures, we define them as either spondylosis, which is a direct um injury to the parse area itself, defined as a complete fracture of the parse interarticularis, and then that can go on to develop as a spontololisthesis, which is defined as a forward translation of one vertebrae segment over the other. Now, typically when you see these in clinic, uh these athletes and or uh patients are going to present with low back pain. Uh, if it is more of a stress reaction type injury, oftentimes it won't be associated with any radiological findings. Uh they could have pain into the buttocks, up into the upper hamstring area. Oftentimes they'll have pain with uh ridicular symptoms, possibly into the L-5 nerve root. Um pretty rarely they'll have bowel and bladder problems. They'll have noticeable limitations, likely increased pain with trunchal extension activities, possibly some limitations with flexion, but flexion may improve their symptoms. Uh they may have some mild provocative symptoms, including straight leg raise, uh, and they may also have an antalgic gait as well. So, again, if we look at the graphic on the screen now, you can see that the pars interarticularis is in that posterior aspect or posterior column. Uh, this often happens secondary to repetitive stress uh to the area. Uh etiology is usually secondary to repetitive hyperextension activities. Uh, this is why we often see this in gymnasts, sometimes in other sports as well. So, again, the most common high-risk sports are gymnastics, football, diving, wrestling, soccer, dance, baseball, and weightlifting. Um, baseball is likely secondary to the hyperextension with throwers. Um, there is uh a peak age. We got to remember that the spine does not finish uh full uh maturation until approximately 25, which is oftentimes why we see this in our younger athletes. Typically, this involves the L5, um, but sometimes can involve the L4 as well. Uh, some of the literature does show that these PARS fractures and/or possible stress reactions of the area can represent up to 47% of low back pain in this young athletic population. So um one in two athletes that you see in come in complaining of chronic low back symptoms, they could have something similar to this uh PARS interarticularis uh fracture or a possible stress reaction to the area. Again, we define uh sponolosis, sponololysis, I apologize, as a fracture within the area, and then sponololysthesis as an anterior slip or a slip on one vertebrae over the other. So again, here you can see via the graphic that when we're looking at these lumbar vertebrates, uh, we have that L5 vertebrae, we have the inner uh vertebral spaces, which is usually um uh composed of that disc. We have to remember that each one of these levels is a different joint, so there's going to be movement within these joints. Ideally, there's stability within the spine, and that stability is created secondary to these pars um area of the vertebrae, which help to uh make up the facet joints, and the facet joints provide the stability between one joint uh to the other with these anterior-posterior translation that could potentially happen. If there is a fracture within the area, they could potentially have that forward slip. So, again, the pathophysiology of these uh secondary to repetitive lumbar extension, possible rotation activities, can be uh chronic, secondary to stress fracture, misofracture, or reaction within the area.

Risk Factors And Imaging Strategy

SPEAKER_00 7:24

Uh risk factors include hyperladosis, tight hamstrings, rapid growth, and early sports uh specialization. If you know these athletes are doing only these single plane uh activities repetitively, especially these extension activities, they could cause increased stress to the area. And again, because we don't have full maturation of the back until approximately the age of 25, this is going to lead to these overstress areas within the lumbar spine symptoms, activity-related low back pain, pain with extension, uh, decreased athletic performance. Again, we all know the red flag symptoms we're looking for when we're looking at the lumbar spine. Oftentimes, the initial imaging can just be an AP and lateral lumbar radiograph. Um, we can do advanced imaging. Most of the time, I'd recommend an MRI. Obviously, with the CT scan, we're gonna expose the athlete or the young patient to possible radiation. So I think the MRI is probably the preferred modality, especially if you're looking at a stress fracture or stress reaction within the area. The MRI is likely going to pick that up better. Specific findings. So on the x-rays, we're looking for that parse defect. You can see it on the oblique view or on Oz, you can see it on the uh direct lateral view, uh, any type of cortical break, that spinal olysthesis, and then that classic Scotty dog appearance that you can often see. So again, you can see on the graphic when we're looking at that lumbar spine x-ray. This is more of the oblique view. You can see the superior articular facet, inferior articular facet, uh, kind of meeting transverse processes, and then you can make out that scotty dog, and if there is a fracture through the neck of that scotty dog, that could represent a possible um parse fracture. Again, limitations of the x-rays are if there's early stress injuries or findings, potentially you won't see those on the x-rays, so that's a clinical exam finding. MRI is the advantage, uh, early detection, especially for those stress reactions. There's no ionizing radiation. Um, oftentimes you'll see some bone marodema, possible cortical injury to that PARS area. And then again, with the CT scan, the limitations are uh radiation exposure. Uh, these can be used for surgical planning if we're going to proceed to the surgical planning um aspect. Different types of classifications um associated with this. Probably the most common classification is really creating the anterior, uh, excuse me, the sponolis, sponolololysthesis, um, and potentially how much anterior translation there is one vertebrae on the other. Um, this is going to quantify uh possible a non-operative versus operative treatment. Ideally, we want to get them before they get to this place. Um, if they're just in that sponololysis uh category, then potentially they can heal quite well and not have long-term side effects. When they get to the spondylolysthesis, uh, the long-term side

Nonoperative Care And Return To Play

SPEAKER_00 10:24

effects become more apparent. Additional non-operative treatment is often associated with um activity modifications, rest from sports, um, anti-inflammatory meds. Uh, braces are a little bit controversial. Uh, some will do bracing for approximately six weeks or so, um, especially in the acute stress reaction to the spondylolysis, as this will prevent uh kind of further hyperextension through the area and help to immobilize the area. But again, not always required. Uh, physical therapy often helps quite a bit, focusing on core strength, improve those dynamic stabilizers around that lumbar spine, uh, improve the hip mobility, um, and then as they're um reducing in symptoms, they could potentially return to sports. Again, bracing uh variable evidence regarding this, typically the brace duration would be six to twelve weeks, um, especially with these stress reactions or these acute symptoms. Return to play. Ideally, the the return to play is a pain-free range of motion. Or excuse me, the uh athlete or patient is completely pain-free. Um, they're able to have normal strength and they're able to participate in sports-specific activities without pain. Uh, image healing is not always required uh if the clinical uh symptoms are asymptomatic. Um, in our patient, uh, we treated her uh non-operatively. Uh, we brace and mobilized her for six weeks. After six weeks, she had improved symptoms. We started in physical therapy activities, and she was gradually able to return to sports activities. Here's her x-ray three months afterwards. Again, you can see that parse fracture a little bit better on this x-ray as that bony reabsorption and healing has gone on. We did try to get possible bone stimulator uh for this patient, but unfortunately wasn't improved uh by insurance uh regarding it. As far as uh operative treatment, surgical indications would typically be fail non-operative treatment, uh progressive sponololisthesis. So if they're uh progressively getting worse, this is where you could get those flexion extension views on the patient to see if there is a progressive or anterior slip, especially positional related slip, uh, that may quantify you for possibly doing surgical treatment. Uh, surgical treatment include direct parge repair. Uh, this can be a screw directly across the area. This is best for young athletes without a significant or major slip. And then some patients they have to do a fusion as well. Uh, this is what that direct repair would look like. So, this is the screw you can see right across uh that pars. This was a unilateral uh fracture, um, and they were able to stabilize it. This can possibly have higher predictability as far as return to sports activities. Outcomes are usually quite good. Uh, most of the time, non-operative treatment can treat this quite well as long as they don't have uh uh sponololisthesis with a significant slip. Uh, that would be a grade three or more, so more than 50% uh slip anteriorly. Typically, patients can do quite well with non-operative and conservative treatment. I think the biggest thing to coach is that um this can take quite a bit of time for them to get better. It can be approximately three to six months before they're able to return to sports-related activities. And there's controversial evidence regarding possible not returning to the sport that caused it, not returning to a sport that causes these hyperextension injuries. Um, you know, we do see these in football linemen because of their chronic extension. Again, uh, oftentimes do see these in

Surgery Prevention And Closing Cases

SPEAKER_00 13:55

um our uh gymnastics athletes, wrestling athletes, anything that is getting into the hyperextension. How can we prevent this? Avoid the year-round overtraining, the repetitive stress to the area. Would recommend uh participating in multiple sports to get uniplanar uh movements and to develop uh improved strength, emphasize core strengthening. So, again, those dynamic stabilizers around that lumber spine can help to protect that spine and get them out of some of those positions, maintain hamstring flexibility, again, monitor training volume, encourage multi-sport participation and proper biomechanics and coaching. Um, some things to remember pain in uh adolescent athletes is not always a muscle strain. Again, uh some literature uh reports that these are in up to 47% uh of patients presenting uh with lower back pain. So, again, uh possibly every other patient you see in this adolescent group complaining of chronic lower back pain could be one of these. Uh pain with extension should raise suspicion, again, for a PARS injury. So if I put them into that extension position and that's a provocative maneuver for them, I'll shut them down. And if they're not improving, then I think getting that MRI can be helpful. Early diagnosis definitely does improve outcome, prevents it from going to that spontalolysthesis and that slippage, and most lastlets can return successfully with conservative treatment. Um, just in passing, so this is another gentleman I saw. Um, he was a 50-year-old male, chronic lower back pain. Uh, he had a parse defect at L5S1, which likely contributed to his low back pain symptoms. Um, has uh also uh developed some significant arthritis um at that L3L4 level above the area. So he presented initially at a clinic uh with a long-standing history of lower back pain. Again, you can see on his x-ray here there's a parse fracture at that L5S1 and possibly some early anterior listesis in that area. Um these are uh his x-rays in the flexion extension views. So again, flexion view, um, leaning back to see if that uh listhesis is worse, and then in the extension view as well. Uh for him, we were able to obtain a CT scan. Um, this is the CT scan on the right here. And again, his was primarily kind of unilateral. So you can see right there, um, if we go back, um that's the parse fracture right there. So you can see the level above and the level that we're looking at. Um, that's our parse fracture there as we're scrolling through. As we get through to the other side, he has uh pretty good articulation, no fracture seen, but did have that unilateral parse fracture. Again, we were able to treat him conservatively, and he was able to do quite well afterwards. So I thought this was an interesting case. Um, just kind of one of those things that we uh see occasionally in clinic, but probably it sees us more often than we see it, um, knowing that a large percentage of patients can have this. I think it's important to remember that these are common overuse injuries, especially in adolescent athletes. Um, extension and rotational loading can be the primary mechanism. MRI can often be useful for diagnosis in these stress reactions. So if you see a young patient in clinic and you try to shut them down and they're not improving with their symptoms, you could obtain that MRI to evaluate for this. Uh may help with um the timing of treatment and how long it's going to take them for to return to sports activities. Conservative management most often is uh effective in these patients, and early recognition can prevent uh progression and possibly chronic problems, especially when they start to develop that uh spontololisthesis that uh could potentially happen. I appreciate you uh listening to this. I hope you found this helpful, and um, we'll uh talk to you on the next one.