Understanding Sacroiliac Joint Dysfunction: Causes and Treatment Options

Deep, aching pain in the lower back that worsens when you sit for long periods, climb stairs, or roll over in bed is a familiar complaint for millions of people. What is far less familiar is the joint most likely responsible for it. The sacroiliac joint, which connects the base of the spine to the pelvis on each side, is one of the most commonly overlooked sources of low back pain in adults. It is frequently mistaken for a disc problem, a hip issue, or general lumbar strain, and as a result, many patients spend months or years pursuing treatments that target the wrong structure entirely.

At Oasis Orthopedic & Spine, proper diagnosis is the cornerstone of effective care, and that begins with understanding what is actually causing your pain. Sacroiliac joint dysfunction is both more common and more treatable than most patients realize, and identifying it accurately opens the door to targeted, meaningful relief.

What the Sacroiliac Joint Does

The sacroiliac joint, often abbreviated as the SI joint, sits at the junction between the sacrum and the ilium — the large, wing-shaped bones of the pelvis. There are two of these joints, one on each side of the spine, and together they serve as the primary load transfer mechanism between your upper body and your lower limbs. Every time you walk, stand up, or shift your weight, the SI joints absorb and distribute force across this critical structural junction.

Despite carrying this significant mechanical load, the SI joints have a very limited range of motion — typically only two to four millimeters in any direction. This combination of high load and minimal movement makes the joint vulnerable to both trauma and degenerative wear over time. According to a clinical review published by the National Center for Biotechnology Information, up to 25% of all low back pain may originate from the sacroiliac joint, making it one of the most prevalent but underappreciated contributors to spinal pain syndromes in the adult population.

What Causes Sacroiliac Joint Dysfunction

Dysfunction of the SI joint typically results from one of two broad mechanisms: too much movement or too little. When the joint becomes hypermobile — moving beyond its normal, tightly constrained range — the surrounding ligaments that hold it in place become strained and inflamed. When the joint becomes hypomobile or locked, the restricted movement creates abnormal stress patterns that produce pain and dysfunction.

Several specific causes drive these patterns, and understanding them is important for selecting the right treatment approach. The most common include the following:

• Trauma: Falls, motor vehicle accidents, and sudden impact to the pelvis can acutely disrupt the SI joint’s structural integrity and trigger both immediate and chronic pain
• Pregnancy and childbirth: Hormonal changes during pregnancy loosen the ligaments of the pelvis to prepare for delivery, and the added weight and postural shifts during this period place significant stress on the SI joints
• Leg length discrepancy: Uneven leg lengths — whether structural or functional — create asymmetrical loading patterns through the pelvis that gradually stress the SI joint on the shorter side
• Degenerative changes: Just as osteoarthritis and joint degeneration can affect other joints in the body, the cartilage of the SI joint deteriorates with age and repetitive stress, reducing its ability to absorb load efficiently
• Prior lumbar spine surgery: Spinal fusion procedures that include the lower lumbar segments can alter load distribution through the pelvis, placing greater mechanical demand on the SI joints

How Sacroiliac Joint Dysfunction Presents

The symptom pattern of SI joint dysfunction is distinct enough that a thorough clinical evaluation can often identify it, though it is frequently confused with other conditions. Pain is typically felt in the lower back and buttock region, often on one side, and may radiate into the posterior thigh in a pattern that closely resembles sciatica. Unlike true sciatica, however, SI joint pain rarely travels below the knee and is not typically accompanied by neurological symptoms such as numbness or weakness in the foot.

Patients commonly report that pain worsens when transitioning from sitting to standing, walking up inclines or stairs, or lying on the affected side. The pain associated with hip pain and SI joint dysfunction overlaps significantly, which is one reason this condition is so frequently misdiagnosed. A key clinical feature that distinguishes SI joint pain from disc or facet-related pain is that it typically follows an identifiable precipitating event rather than developing insidiously over time.

Diagnosing Sacroiliac Joint Dysfunction

There is no single imaging study or physical examination finding that definitively confirms SI joint dysfunction. Diagnosis relies on a combination of clinical history, provocation tests that stress the joint in specific ways, and in many cases, a diagnostic injection of local anesthetic into the joint. When the injection produces significant, temporary relief, it confirms that the SI joint is the source of pain and guides the treatment strategy that follows.

This is one reason why evaluation by a spine and orthopedic specialist is so important. The diagnostic process for SI joint dysfunction requires clinical experience and a systematic approach to ruling out other potential pain generators in the lumbar spine, pelvis, and hip region.

Treatment Options for Sacroiliac Joint Dysfunction

The good news is that most patients with SI joint dysfunction respond well to non-surgical treatment options when they are appropriately targeted. Treatment typically begins conservatively and escalates based on how the patient responds. The most established approaches include the following:

Activity modification and physical therapy focused on stabilizing the pelvis and strengthening the musculature that supports the SI joint are usually the first line of treatment. When these measures provide insufficient relief, pain management strategies such as anti-inflammatory medications or corticosteroid injections directly into the SI joint can significantly reduce inflammation and restore function. For patients with persistent, severe dysfunction that does not respond to these measures, minimally invasive SI joint fusion procedures are available. These involve placing small implants across the joint to stabilize it permanently, and outcomes data for appropriately selected patients are consistently favorable.

Get Accurate Answers at Oasis Orthopedic & Spine

At Oasis Orthopedic & Spine, our team of specialists is experienced in diagnosing and treating the full spectrum of sacroiliac joint conditions across New Jersey. We take a methodical approach to evaluation that ensures your treatment targets the actual source of your pain — not a neighboring structure that happens to share a similar symptom profile. Whether you have been dealing with unexplained lower back and pelvic pain for years or are newly seeking answers after a trauma or pregnancy, we are equipped to give you clarity and a clear path forward.

Living with unresolved back pain is not inevitable. Request an appointment with Oasis Orthopedic & Spine today and take the first step toward a diagnosis and treatment plan that actually fits your condition.