by Paul Wright
Pain in and around the area of the sacroiliac joint (SIJ) is a complaint frequently seen by physiotherapy and sports physicians, especially if they are associated with gymnastic, jumping and running-based athletes. Pain and discomfort in this region of the lower back can be due to referred pain from the lumbar spine discs, facet joint referrals and various bursitis and ligamentous conditions. However, a common cause of low back pain, and the topic of this issue’s article, is pain originating from the SIJ.
It is only recently that the medical profession has developed an interest in the SIJ as a cause of low back pain, as this complex joint was originally thought to be completely immobile and is difficult to examine clinically.
Medical experts differ in their opinion of the prevalence of SIJ involvement in chronic low back pain, however it is thought that between 13 and 30 per cent of all low back pain may actually be referred from the SIJ and not therefore be caused by a specific lumbar spine problem at all.
ANATOMY AND PHYSIOLOGY
The SIJ is classified as a diarthrodial joint (meaning it has a synovial component at the front and a fibrous part at the rear) between the sacrum and the pelvis. The joint is basically ‘C’ shaped and contains many ridges and troughs which create a high friction between the surfaces, further re-enforcing the fact that the joint’s primary function is one of stability and not motion.
The joint is well supported by a complex network of deep and superficial ligaments, such as the interosseous ligaments and the important sacrotuberous ligament, which provide resistance to the high shearing and loading forces that are transferred through the SIJ with walking, jumping and running activities. The joint is further supported by muscular structures such as the piriformis, biceps femoris, gluteus maximus and minimus, erector spinae, latissimus dorsi, thoracolumbar fascia and iliacus.
SIJ movement has been explained as a combination of flexion and extension, translation forwards and backwards, and superior and inferior glide – this complex combination of movements has been termed nutation and counter-nutation. While the available movements listed above may sound impressive, in real terms the SIJ can only rotate an average of 2.5 degrees, or about 0.7mm. Because of the very small range of available movement, however, any appreciable increase in range or loss of range can lead to pain and discomfort.
SIGNS AND SYMPTOMS
The patient with SIJ issues usually describes their pain as a dull ache or a sharp stabbing pain in or near the joint line and into the buttock region. However, it is not uncommon for the pain to travel down into the posterior thigh and even as low as the calf, making examination and assessment even more difficult.
Activities such as negotiating stairs, rising from sitting to standing and rolling over in bed have been linked to problems with the SIJ. In the fitness facility setting, exercises such as step ups and lunges and cardiovascular equipment such as the stepper and incline treadmill also place significant strain on this area of the body.
On examination the patient may have obvious asymmetry of the posterior superior iliac spines (PSIS) in standing and when flexing forward. This is also associated with abnormalities in the alignment of the anterior superior iliac spine (ASIS) at the front. These observations can indicate some disruption to the general positioning of the pelvis as a base for the sacrum and the spine.
The therapist is also able to assess the SIJ by attempting to move one iliac crest on the other, force the ilium together and by moving the hips into specific positions that place stress on the SIJ and reproduce pain to assist in accurate diagnosis. Some medical professionals also use injections of local anaesthetic and corticosteroid to assist in diagnosis, and also treatment if more conservative measures fail.
As with all episodes of pain it is essential the client is examined by a physiotherapist or sports physician as soon as possible. The medical professional will evaluate the extent of the injury, determine an accurate diagnosis and chart the most appropriate management strategy to return the client to full function. This is especially applicable in patients with low back pain due to the complexity of problems and referral of pain from other areas.
Effective management of SIJ problems involves initial reduction in inflammation and correction of biomechanical problems – this can involve such strategies as manual therapy to restore joint motion, soft tissue releases to reduce pain from muscular and ligamentous origins, and mechanical interventions such as heel raises (to modify pelvic asymmetries), orthotics and taping techniques to stabilise and control unwanted motion and reduce muscular load.
An important component of the rehabilitation process is the need for an effective strengthening program to restore pre-injury function. The majority of exercises should be performed pain-free with close attention being paid to any post•exercise pain and especially increased pain the morning after a rehabilitation session. The need for appropriate strengthening must be balanced with possible aggravation of symptoms.
A common clinical indicator to predict and treat SIJ problems is the lack of inner range hip extensor strength, best assessed by using the ‘Prone Hip Extension Test’ (see photo 1). This test is based on the assumption that any lack of strength in the hip extensors (primarily gluteus maximus) at end of range (i.e., when the hip is at or near 180 degrees of extension) will leave the SIJ in an unstable position at heel strike and thus vulnerable to injury. This may be one of the reasons that cyclists who commence a running program are at risk of SIJ problems as they have not effectively trained the gluteals at end of range.
It is also vital that the patient embarks on a sound core stability program in conjunction with specific rehabilitation of the SIJ problem as many SIJ issues can be linked back to poor pelvic stability. This is especially common in women post pregnancy as the broader pelvis of the female, in conjunction with ligamentous laxity brought on by pregnancy, can lead to chronic SIJ problems.
The progression of the strengthening program and a gradual return to full running and cross-training activities should always be overseen by the treating physiotherapist or sports physician, as reinjury and poor recovery are often caused by over-enthusiastic patients and premature return to sport.
Paul G Wright, BAppSc (Physio) DipEd (PE)
Paul is the director of Get Active Physiotherapy Health Centres with clinics inside Fitness First clubs at St Leonards (Sydney) and Kotara (Newcastle) as well as a Head Office in the CBD of St Leonards. He has produced a series of injury prevention and training DVD s for fitness professionals, including episodes focusing on the lumbar spine and sacroiliac joint rehabilitation. For more information, visit www.getactivephysio.com.au or call 02 9966 9464.
NETWORK • WINTER 2008 • PP33-34