FAQ for Patients
Answers to some of the most common questions
FAQ for Patients
Answers to some of your most common questions
The sacroiliac (SI) joint is the largest joint in the body, joining the bottom of the spine (sacrum) to the iliac bones on either side, which attach to the hip joints. Therefore, the SI joints are very important in transmitting the compressive forces on the spine to the hips and legs. While the SI joints normally move very little in daily life, they serve an important role in pregnancy and childbirth due to their ability to expand and allow for delivery through the birth canal. Otherwise, the joints move within a range of only a few millimeters. However, certain conditions can cause pain in the joints even despite the small degree of movement. Most commonly, SI dysfunction is seen in patients who have had lower back fusion surgeries due to the increased stress and stress on the SI joints, or in some females who develop instability in the joints after childbirth. Other factors may predispose to SI pain, like variant lumbosacral anatomy that places more stress on the joints, or a history of physical trauma such as motor vehicle collisions.
Diagnosing pain originating from the SI joint can be difficult because it can present in several different ways. Most commonly, SI joint pain is felt in the very low back on one or both sides, but may also be felt in the hip, buttocks, or with shooting pain down the back of the leg (a condition called “pseudo-sciatica”). SI pain is usually worse with walking and standing, but can also cause pain with sitting. Because several other sources can cause similar types of pain, including the lumbar spine and the hips, it is important for the diagnosis of SI joint pain to be made by an experienced physician with expertise in SI dysfunction.
Several different factors are important to determine whether pain is coming from the SI joint. First, your history provides important clues, including history of spine surgeries, childbirth, or physical trauma, as well as characteristics of the pain and the factors that make it better or worse. Imaging including MRI or CT of the lumbar spine and pelvis may provide important information including degenerative changes of the SI joints, surgical changes, or variant anatomy, though it is important to know that the diagnosis cannot be made on imaging alone. Next, your physician will perform several physical exam tests which may provoke pain originating from the joint. Based on these factors, a tentative diagnosis of SI dysfunction may be made. This is then confirmed with an injection of medication (anesthetic such as lidocaine or bupivacaine, with or without liquid steroid). If the joint is the cause of the pain, the pain should be mostly or completely relieved shortly after the injection. The pain relief is often confirmed with a 2nd confirmatory injection at a later time.
Depending on the severity of the pain, conservative options like anti-inflammatory medications, activity modification, or physical therapy may be considered. SI joint injection can provide a therapeutic benefit of several weeks or months in some patients, though it tends to be short-lived in most patients and is mostly used as a diagnostic procedure as described above. Ablation (also called rhizotomy) of the nerves to the SI joints using radiofrequency energy needles has shown to provide pain relief, albeit temporary since the nerves grow back over the course of several months. Like other chronic pain conditions, systemic opioid medications are not usually considered a good chronic therapy for SI dysfunction, because they do not treat the cause of the pain and lead to decreased pain tolerance and additional side effects.
If more conservative options have not provided durable relief for your SI joint pain, you and your physician may discuss SI joint fusion. SI fusion is very different from other fusion surgeries because it does not cause downstream issues on adjacent joints in the hips or lower back. It is also a much less invasive procedure than the majority of spine fusions.
In the past, SI fusions were mostly performed with an open surgical approach utilizing a relatively large incision, soft tissue dissection, and placement of bone graft or other fusion devices into or across the joint. Modern SI fusion techniques use minimally-invasive (MIS) approaches with small incisions and image-guidance to accomplish the same goal. This allows for minimal blood loss, less postoperative pain, and quicker recovery. Several different techniques have been developed, and your physician may use a specific approach based on your specific anatomy, presence of other hardware like sacral pedicle screws or iliac screws, and their own preference and expertise.
The majority of SI fusions are performed on an outpatient basis (day surgery), although this will depend on several factors including your health factors, insurance specifics, and the facility where the procedure is performed.
Overall, you can expect several weeks of soft tissue soreness from the procedure and a gradual decrease in the level of pain from your SI joint. Like other fusion surgeries, the fusion takes several months to solidify, so you should expect for your pain to gradually decrease over the course of several months to weeks, and not instantaneously. On average, the pain relief from SI fusion is not maximized until 6 months after the procedure.
Yes. Clinical trials and other studies of SI fusion have shown durable relief of SI pain which maximizes around 6 months after surgery and tends to stay durable from that point onward.
Most causes of recurrent pain after SI fusion are due to another source of pain such as lumbar spine or hip. Rarely, the joint may fail to fuse due to physical trauma like a motor vehicle collision, or poor bone mineral quality causing loosening of the hardware. For this reason, patients with osteoporosis are not considered good candidates for SI fusion without preceding treatment to increase their bone mineral density.
SI fusion is covered by Medicare and most commercial insurances in the US. Certain insurance carriers may have specific prerequisites for surgery including trials of conservative therapies such as physical therapy, imaging such as CT of the pelvis to ensure there are no alternate causes of the pain that should be treated first, and often a confirmatory SI joint injection before proceeding to fusion. Please consult the details of your plan to find out your specifics.
Most patients will have soreness in the area of the surgery for several weeks, which will gradually decrease as with any surgery. Some bruising may occur in some patients and is not usually a cause for concern. Because the size of the incisions and degree of soft tissue disruption is less than many fusion surgeries, the typical recovery time is also much shorter. A short course of pain medication will usually be provided to help with incisional pain, and this should be tapered and discontinued usually within the first week of surgery. You should expect to take several days to rest and recover from the surgery, but walking and normal, non-strenuous activity is encouraged early after surgery. Your SI joint pain should gradually improve; some patients experience great relief early on, while others take more time.
Your physician will instruct you of specific restrictions after your surgery, but in general you should anticipate no heavy lifting or other strenuous activity at least until your first postoperative visit and possibly for several weeks or months. Normal activity like walking is encouraged to avoid deconditioning, which could hinder your recovery. At your post-operative visit, your physician may recommend physical therapy to assist in recovery. PT may not be necessary for all patients.
Nonsteroidal anti-inflammatory drugs (NSAIDs) like ibuprofen are avoided in the early post-operative period because of the potential to interfere with bone healing.
Because vaginal delivery depends on the ability of the SI joints to expand, fusing the joint will interfere with this natural movement. The state of pregnancy also depends on the ability of the SI joints to move and expand to make room for the growing uterus, so females with plans for future childbearing are not considered good candidates for SI fusion surgery. If you have concerns related to potential future pregnancy, discuss them with your physician to find a care plan that works for you.
