Jan 29, 2015Back-Fixing Work
When an athlete presents with low back pain, the cause may be sacroiliac joint dysfunction (SIJD), an injury that continues to confuse sports medicine providers.
By Dr. Per Gunnar Brolinson, Mike Goforth, and Dr. Mark Rogers
Per Gunnar Brolinson, DO, is Associate Dean for Clinical Research and Director of the Primary Care Sports Medicine Fellowship at the Edward Via College of Osteopathic Medicine (VCOM)-Virginia Campus and serves as Head Team Physician at Virginia Tech. Mike Goforth, MS, ATC, is Associate Director of Athletics for Sports Medicine and Head Athletic Trainer at Virginia Tech, as well as a clinical instructor in sports medicine at VCOM. Mark Rogers, DO, CAQSM, is an Associate Team Physician for Virginia Tech and Associate Program Director for the Primary Care Sports Medicine Fellowship at VCOM. Dr. Brolinson can be reached at: [email protected].
Few medical conditions common to athletics are as misunderstood and misdiagnosed as sacroiliac joint dysfunction (SIJD). Despite being an established clinical entity, SIJD is difficult to evaluate and treat due to complex anatomy and biomechanics and unreliable diagnostic tests. Our clinical experiences have shown that about 50 percent of athletes with mechanical low back pain have SIJD, yet the condition has been largely unstudied. SIJD refers to pain, sometimes debilitating, in the region of the sacroiliac joint (SI joint) that is caused by inflammation of the joint and surrounding soft-tissue structures. This inflammation usually results from either too much or too little motion in the SI joint. It can also be caused by acute physical trauma, such as landing hard on the buttocks, or certain movement patterns that place enough biomechanical stress on the lumbosacral-pelvic region to affect the motion of the SI joint and lead to SIJD.
The SI joint is part of an area composed of the lumbar spine and pelvis known as the lumbosacral-pelvic region, which is the link between the upper body and lower body. Biomechanical forces from the upper extremities and torso are transferred through the region to the lower extremities, and vice versa. Therefore, SIJD can affect athletic performance in a significant way.
ANATOMY & BIOMECHANICS
The complex anatomy and biomechanics of the SI joint have made it difficult to map out specific diagnostic and treatment protocols for SIJD. In an adult, it is an L-shaped articulation of the pelvis with a long upper vertical pole and a short lower horizontal pole. Some have described this as an S- or C-shaped articulation. The anatomy and biomechanics of the SI joint relates to the entire lumbosacral-pelvic region. From an anatomical perspective, this region is best understood as a continuous, ligamentous stocking formed by interconnections of various regional ligaments and fascial structures. This stocking is the primary support of the osseous elements throughout the lumbosacral-pelvic region and is anchored through the thoracolumbar fascia of the back and the hamstring-sacrotuberous ligament complex of the pelvis. The continuous nature of this ligamentous stocking gives the entire region its interdependent functionality.
The stocking also includes a large sheet of fascia that serves as the attachment site for multiple major muscle groups of the spine, abdomen, and upper and lower extremities. Biomechanical forces that transfer through this region may be under the proprioceptive control of neural elements within the fascia. Besides their role in the maintenance of normal tissue tension and the propagation of possible prolonged inflammatory responses, the interactive role of these neural elements are essential to the normal trophic activity of this tissue. The stability of the lumbosacral-pelvic region is dependent upon these muscular and ligamentous relationships and it is their breakdown and degeneration that can lead to chronic pain. One of the factors that complicates the anatomy is that no two SI joints are alike. Significant variability exists between individuals with respect to size, shape, and surface contour. There are two primary reasons for this variability. The first is genetics, the predominant determiner of bone formation. The second reason is that everyone carries their biomechanical loads differently. For example, tall or heavy individuals will load the joint differently than short or light people. The fact that there have been conflicting studies regarding the possible mobility or immobility of the SI joint has caused further difficulties in diagnosing SIJD. For some time, it was generally accepted that there was motion in the joint early in life, but that degeneration reduced this motion over time. However, it is now generally accepted that motion in the SI joint occurs throughout a person’s lifetime.
Integral to the biomechanics of SI joint stability is the concept of a “self-locking mechanism.” The SI joint is the only joint in the body to have a flat-joint surface that lies almost parallel to the plane of maximal load. It appears to have the ability to self-lock through two types of closure: form and force. Form closure describes how specifically shaped, closely fit contacts provide inherent stability independent of external load. Force closure describes how external compression forces add additional stability. It had long been thought that only the ligaments in the lumbosacral-pelvic region provided form closure. However, it is the fascia and muscles within the region that provide significant self-bracing or self-locking mechanisms to the SI joint and its ligaments through their cross-like anatomical configuration. Additionally, there appears to be force closure through an arthrokinetic reflex mechanism used by the nervous system to actively control this added support system. These supports are critical in sport movements that create asymmetric loading in which the SI joint is most prone to subluxation. Instability often occurs as a result of the loss of functional integrity of any of the stabilizing systems of the lumbosacral-pelvic region. The myofascial or osteoarticular and ligamentous components may be affected, as with chronic spondylolisthesis. It’s important to understand this concept because it implies that a thorough evaluation of the lumbosacral-pelvic function must be carried out in the evaluation for SIJD, irrespective of where the pain originates.
SIGNS & SYMPTOMS
There is no single examination technique specific to the diagnosis of SIJD. To date, imaging studies do not distinguish asymptomatic from symptomatic athletes. Therefore, accurate diagnosis must be based on a combination of pertinent historical clues picked up from information provided by the athlete and a thorough physical exam that looks for the nuances of this condition. The following elements of a patient’s history should be collected to better understand the nature of the injury: Age: This is important because many conditions common to the lumbosacral-pelvic region occur within different age ranges, such as ankylosing spondylitis and osteoarthritis. Sport: Typically, athletes involved in sports that tend to load the pelvis repetitively in an asymmetric fashion are at greatest risk for developing SIJD. Some examples are golf, tennis, volleyball, baseball, softball, and football.
Mechanism of injury: It’s essential to determine whether SIJD results from an acute traumatic injury or a chronic repetitive injury. Traumatic SIJD is typically easier to diagnose because there is usually pain immediately associated with an injury, which makes it more likely that the athlete will recall how it occurred. In addition, this type of SIJD tends to respond more quickly to manual therapy aimed at restoring joint alignment and function, as well as brief periods of therapeutic exercise with pain-control modalities. Chronic repetitive SIJD is typically more difficult to diagnose and treat. Some of the most challenging cases we’ve seen over the years have involved football punters and place kickers. In order to develop their sport-specific skill set, they have to kick the ball repetitively, which places asymmetrical biomechanical stress on the lumbosacral-pelvic region that is the cause of the pain and dysfunction. Pain: Get an accurate assessment on the acuteness, duration, and frequency of pain. In SIJD, the pain is usually constant, unilateral, dull, and deep. Often, it isn’t limited to the SI joint but will radiate to the buttocks, posterior thighs, or groin area. Inquiring about what treatments the athlete has already tried to help improve symptoms can also provide clues for a thorough diagnosis.
Previous injuries: Patients should provide a complete injury history, including treatments and outcomes, which can provide valuable clues to aid in the diagnosis. For example, when an athlete sustains an injury to a lower extremity joint that causes a limp, the altered gait pattern may create an asymmetric loading of the pelvis and SI joint, which can result in SIJD.
The physical exam includes observing an athlete in both static and dynamic positions. In the static position, symmetry should be assessed in the heights of the iliac crests, anterior superior iliac spines, posterior superior iliac spines, ischial tuberosities, gluteal folds, greater trochanters, sacral sulci and inferior lateral angles, and pubic tubercles. Signs of asymmetry may indicate SIJD. Posture should also be examined for increased lumbar lordosis, which can result from sacral torsions.
Next, determine if any leg-length discrepancies exist. True discrepancies in leg length will generally cause asymmetry and pain, whereas a functional leg-length discrepancy is usually the result of SIJD and/or pelvic dysfunction.
Functional leg-length discrepancies typically result from an anteriorly or posteriorly rotated pelvic bone. Because the acetabulum is eccentrically loaded from the axis of rotation of the pelvic bone, the rotation can result in a functionally short or long leg, depending on the direction. This occurs despite the tibias and femurs being the same length anatomically. Anatomically speaking, the sacrum and lumbar spine move in opposite directions in the sagittal plane. Therefore, when the base of the sacrum moves anteriorly, there is an increase in the lumbar lordosis. The converse is also true.
During the dynamic observation, the examiner should assess any asymmetry during both gait and motions unique to the patient’s sport. SI joint pain, pathology, and restriction may cause asymmetries such as a decrease in stride length that leads to a limp or a reflex inhibition of the gluteus medius that can cause a Trendelenburg gait. The examiner should also look for decreases in both passive and active range of motion of the spine, hips, and knees. If pain occurs during motion testing, the patient should identify the source. Pathologies in these areas can radiate pain to the SI joint. A neurological examination for radiculopathy should also be conducted in addition to evaluating core strength.
There are numerous functional and provocative tests available for SIJD but none have proven exclusively reliable in diagnosing the condition. In addition, many assume that pain production is an essential prerequisite to dysfunction. We feel that SIJD can be diagnosed based solely on motion restriction and tissue-texture changes. When there is an overuse mechanism of injury, the SI joint typically becomes dysfunctional before it becomes painful. For example, athletes that are well tuned to their bodies may notice motion restriction and performance decline before they experience pain in the SI joint. As it becomes increasingly dysfunctional, clinicians may begin to notice that the tissues surrounding it feel differently on palpation than normal, and the athlete may experience tenderness in the area. This generally indicates that SIJD has developed. The screening tests we commonly use in the evaluation of SIJD are standing and seated flexion tests, stork (Gillet), Gaenslen, supine-to-sit, FABER (Flexion, ABduction, External Rotation) test, and side-lying approximation and supine gapping. Careful palpation and observation of pelvic and sacral bony landmarks can also be valuable. SIJD screening tests should always be followed up with segmental motion testing and tissue palpation. When used together with a thorough history, these tests become significantly more reliable, much like physical exam tests for meniscal tears. However, a common mistake is giving too much weight to the results of an individual test when making a diagnosis. There are a number of tests for SIJD, but no single test is diagnostic of the condition. To increase the sensitivity and specificity of the examination, clinicians should employ several different SI physical exam techniques. In addition, a “diagnostic” anesthetic injection into the SI joint area can often help identify the etiology of pain in challenging cases.
There is also no gold standard imaging test to diagnose SIJD, due in large part to the SI joint’s location and overlying structures, which make visualization difficult. However, standard radiographs taken at 25 to 30 degrees from the anterior-posterior axis and lateral views may show degenerative changes, ankylosis, demineralization, or fracture. Degenerative changes are usually first noted on the iliac side of the joint. If sclerosis involves the lower two-thirds of the joint on both sides, sacroiliitis is a primary diagnostic consideration. It should also be noted that the SI joints in adolescents can show widening and irregularity, which can make it difficult to diagnose SIJD radiographically. Individual physical exam testing procedures also appear to be unreliable as the sole diagnostic tool, so SIJD is best evaluated by applying a consistent palpatory and functional examination technique. Accurate diagnosis is always based on a combination of historical clues and findings from static palpatory exams, segmental and regional motion testing, and an overall functional biomechanical examination and appropriate diagnostic testing.
TREATMENT Our experience is that a multimodal approach that includes SI joint mobilization or manipulation usually works best in the treatment of SIJD. We also teach the athlete how to find and fire the transversus abdominus muscle. Identification and correction of functional or anatomic leg-length discrepancy is another important but often-overlooked clinical approach, and the influence of proximal or distal structures must be considered, especially with regard to postural retraining. Finally, the biomechanical demands of the athlete’s sport must be accounted for when designing the rehabilitative environment. We are typically not modality driven at Virginia Tech. We utilize modalities in our treatment protocols if clinically indicated, with ice and/or heat being the most common. Instead, we emphasize therapeutic core and pelvic stability exercises and gradually reintroduce the loads and motions of the athlete’s sport in a clinically controlled and calibrated manner. (For a more in-depth look at our treatment protocols, see case studies below.)
Recognizing and treating SIJD is a challenge, but it’s certainly not impossible. A combination of understanding the complex anatomy and biomechanics behind the syndrome, completing thorough exams, and carefully performing a variety of screening tests can result in a successful diagnosis. And when the right treatment protocol is added to the mix, athletes with SIJD can get back in the game in no time.
Case Study One: Acute Traumatic SIJD
In November of Virginia Tech’s 2013-14 football season, a junior wide receiver sustained an injury to the left sacral area after an impact to the buttocks from an opposing player’s knee. He was in immediate pain following the incident and unable to return to the game, but denied radicular symptoms, saddle anesthesia, and incontinence/retention. He continued to have soreness and bruising in the sacral area the following day and a physical exam noted ecchymosis at the base of the sacrum on the left flank and focal tenderness at the left sacral base and coccyx. There was no palpable crepitus over the sacrum or coccyx and the player had full range of motion in the lumbar spine and bilateral lower extremities, which were neurovascularly intact. His leg lengths were equal but a FABER test for left sacroiliac joint pain was positive, along with standing and seated forward flexion tests on his right side. Radiographs of the lumbosacral spine showed evidence of a minimally displaced fracture in the distal sacrum/coccygeal area. The player was diagnosed with left sacroiliac joint dysfunction (SIJD) with right-on-left sacral torsion, a coccygeal fracture, and a sacrum/buttock soft-tissue contusion. His treatment included a local anesthetic blockade consisting of 4 ml of 1% lidocaine and 4 ml of 0.25% bupivacaine–both without epinephrine–applied to the fracture site, osteopathic manipulations two to three times a week to treat the right-on-left sacral torsion and anterior innominate pelvic rotation, and he was fitted with a custom pad to protect the injured area. The anesthesia injection was used once before a practice and the player was able to participate without restrictions, experiencing only minimal discomfort. He returned to competitive action a week after the injury and the anesthesia was used again as part of a new treatment regimen. Before each of the next two games, in addition to the anesthetic blockade, he received oral doses of 20 mg of ketorolac and 37.5/325 mg of tramadol/acetaminophen. After successfully competing in both games, he was able to participate for the rest of the season without the anesthetic blockade. With only a custom sacral pad added to the above regimen, the player remained healthy for the rest of what turned out to be a great season for him. His 51 pass receptions were a team high and fifth-most in Virginia Tech history, and he also led the team in receiving yards with 635.
Case Study Two: Chronic Repetitive SIJD
In the fall of 2012, a sophomore and right-handed outside hitter on Virginia Tech’s women’s volleyball team reported experiencing right-sided low back pain ahead of the season following a challenging preseason practice. She had a remote history of bilateral L5 pars fractures when she was in high school but had been symptom-free for some time. The onset of the low back pain was insidious and without trauma. She noted a dull pain in the right buttock area that became worse with extension, right rotation, and side-bending. She did not experience any fever or chills, nighttime pain, abdominal pain, true radicular pain, incontinence, weakness, or paresthesias. On physical exam, her gait was steady and a motor and neurovascular exam was normal but her right hamstring, rectus femoris, and psoas were tight. Her right leg was shorter by about 5 mm and her right pelvic bone was anteriorly rotated on the right side. Standing flexion and Gaenslen’s tests were positive on her right side and a positive FABER test reproduced her pain in the area of the right sacroiliac (SI) joint. She also had a delayed gluteus muscle firing pattern and was tender to palpation in the area of the right SI joint, but not on the lumbar spine, and she had a right-on-right sacral rotation. Lumbar spine radiographs showed chronic-onset bilateral L5 pars articular fractures without listhesis or sclerosis at the SI joint, and her L2-4 vertebrae were rotated to the right and side-bent to the left. She was diagnosed with sacroiliac joint dysfunction (SIJD), functional leg length discrepancy, sacral and pelvis rotations, abnormal muscle firing patterns, and history of L5 pars fracture.
In addition to ice and nonsteroidal anti-inflammatories (NSAIDs), which helped her symptoms, her treatment included osteopathic manipulation to her lumbar spine, sacrum, and pelvis to improve her dysfunctional patterns and resolve her functional leg-length discrepancy. She also underwent functional rehabilitation to her core, pelvis, and lower extremity muscles. Her symptoms improved but they did not resolve until we initiated a series of prolotherapy injections in the affected SI joint, which successfully increased stability in the SI joint complex. Manipulation and therapeutic exercise improved structural and functional relationships and contributed to her overall clinical improvement. Her dysfunctional movement patterns and symptoms resolved and she was able to return to competition and have a successful season.