Find the source of your lower back pain. Find the fastest path to lasting relief.
A sacroiliac (SI) joint injection is a precision, image-guided injection placed into the SI joint where the base of the spine connects to the pelvis. The procedure serves two purposes in one visit: it confirms whether the SI joint is the source of chronic lower back and buttock pain, and the corticosteroid component can provide weeks to months of therapeutic relief.
SI joint injections are for adults in the Princeton corridor with chronic lower back, buttock, or one-sided hip pain that has not improved with physical therapy or medication, including Bristol Myers Squibb researchers, ETS staff, attorneys, faculty at the Lawrenceville School and Rider University, healthcare workers, and active-adult retirees across Mercer and Hunterdon counties. They are also the first diagnostic step before lateral branch blocks and radiofrequency ablation. Discseel® evaluation is available for select discogenic back pain cases.
or call 609-588-8600 · Lawrenceville-area office
By the Pain Management Team at Performance Pain and Sports Medicine
Matthias Wiederholz, MD · Jade Nemeth, PA-C
Updated May 2026
On This Page:
- What Is the Sacroiliac Joint?
- What Causes SI Joint Pain?
- Symptoms of SI Joint Dysfunction
- How SI Joint Injections Work
- What to Expect During the Procedure
- Recovery and Results
- Risks and Side Effects
- When SI Joint Injections Are Not Enough
- Cost and Insurance
- SI Joint Injections at Our Lawrenceville Office
- Frequently Asked Questions
Lawrenceville sits at the center of the Princeton corridor pharmaceutical and research industry, between New York City and Philadelphia, with a patient population that includes Bristol Myers Squibb research scientists, ETS staff, attorneys and finance professionals commuting on the Northeast Corridor line, Lawrenceville School and Rider University faculty, healthcare workers across Penn Medicine Princeton and Capital Health, and active-adult tri-state retirees throughout Mercer and Hunterdon counties. The unifying thread is years of high-load desk work or active living, often interrupted by chronic lower back and buttock pain that no longer responds to rest, physical therapy, or oral medications. Research estimates that the sacroiliac (SI) joint is responsible for 15 to 30 percent of all chronic low back pain cases (Szadek et al., Pain Practice, 2023), yet it is frequently underdiagnosed because its symptoms overlap with disc and hip conditions.
A sacroiliac joint injection is a minimally invasive, image-guided procedure that serves two purposes: it can confirm whether the SI joint is the source of your pain, and it can deliver targeted anti-inflammatory medication to reduce it. At Performance Pain and Sports Medicine in the Lawrenceville area, Dr. Matthias Wiederholz, MD performs SI joint injections using fluoroscopic (real-time X-ray) guidance for precise needle placement. Conservative, non-surgical spine treatments are always explored first. The Lawrenceville-area office is located on Quakerbridge Road, just off Route 1, and serves the Princeton corridor and broader tri-state community.
What Is the Sacroiliac Joint?
The sacroiliac joints are two large joints located where the base of the spine (the sacrum) connects to the pelvis (the iliac bones). You have one on each side of your lower back, just below the belt line.
These joints act as shock absorbers between the upper body and the legs. They transfer the weight of your torso to the pelvis and lower extremities during standing, walking, and sitting. Strong ligaments surround the SI joints to limit their range of motion and provide stability (Gartenberg et al., European Spine Journal, 2021).
When the SI joint becomes inflamed, hypermobile, or stiff from degeneration, it can produce pain that is often mistaken for a herniated disc or hip problem. Because the SI joint sits deep within the pelvis and lacks a distinctive pain pattern, it is frequently underdiagnosed as a source of chronic lower back pain.
What Causes SI Joint Pain?
Research estimates that the SI joint is responsible for 15 to 30 percent of all chronic lower back pain cases (Szadek et al., Pain Practice, 2023; Cohen et al., Expert Review of Neurotherapeutics, 2013). Despite how common it is, SI joint dysfunction often goes unrecognized for months or years because its symptoms overlap with other spinal conditions.
Common causes of SI joint pain include:
- Trauma or injury, such as a fall, car accident, or impact during sports
- Pregnancy and childbirth, which loosen the pelvic ligaments and increase joint stress
- Prior lumbar spine surgery, which can shift mechanical loads onto the SI joint (Horton et al., JBJS, 2024)
- Degenerative arthritis, particularly in adults over age 50
- Gait abnormalities or leg length differences that create uneven stress on the pelvis
- Repetitive stress from activities like running, heavy lifting, or prolonged sitting
For patients in the Princeton corridor dealing with persistent back pain that has not responded to conservative treatments, a thorough evaluation of the SI joint should be part of the diagnostic workup. Patients with a history of lumbar fusion are particularly at risk because the SI joint takes on additional mechanical load, a pattern Dr. Wiederholz sees often in patients with prior spine surgery at Penn Medicine Princeton, Capital Health, or RWJBarnabas.
Symptoms of SI Joint Dysfunction
SI joint pain typically presents as a deep, aching discomfort on one side of the lower back or buttock. The pain often extends into the hip or upper thigh, which is why it is frequently confused with sciatica or hip joint problems.
Common symptoms include:
- Pain in the lower back, buttock, or hip that is usually worse on one side
- Pain that worsens with prolonged sitting, standing, climbing stairs, or rolling over in bed
- Stiffness in the pelvis or lower back, especially in the morning
- Pain during transitions, such as standing up from a seated position or getting out of a car
- Difficulty with activities like walking, bending, or lifting
A clinical review in American Family Physician notes that when three or more physical provocation tests reproduce a patient’s typical pain pattern, this strongly suggests SI joint dysfunction as the source (Newman & Soto, American Family Physician, 2022). If your symptoms match this pattern, a diagnostic SI joint injection can confirm or rule out the joint as the pain generator.
How SI Joint Injections Work
SI joint injections serve two purposes: diagnosing the source of pain and treating it. This dual role makes them one of the most important tools in evaluating chronic lower back and pelvic pain.
Diagnostic SI Joint Block
When a physician suspects the SI joint is causing your pain, a diagnostic block is performed first. A small amount of local anesthetic is injected directly into the SI joint under fluoroscopic (real-time X-ray) guidance. If you experience significant temporary pain relief, this confirms the SI joint as the pain generator.
This step is critical because SI joint pain can mimic disc, facet, or hip problems. The diagnostic block removes guesswork and ensures that any further treatment targets the correct structure. Research supports the use of provocation testing followed by diagnostic blocks as the standard approach for confirming SI joint dysfunction (Buchanan et al., Journal of Pain Research, 2021).
Therapeutic SI Joint Injection
Once the SI joint is confirmed as the source, a therapeutic injection combines local anesthetic with a corticosteroid medication. The anesthetic provides immediate short-term relief, while the corticosteroid reduces inflammation within the joint over the following days.
A randomized controlled trial found that fluoroscopy-guided corticosteroid injections significantly reduced pain and disability scores compared to placebo at both two and four weeks after the procedure (Patel et al., Cureus, 2023). Joint guidelines from ASRA, AAPM, ASIPP, and SIS support the appropriate use of corticosteroid injections across musculoskeletal pain conditions (Benzon et al., Regional Anesthesia and Pain Medicine, 2025).
Recent clinical practice guidelines have questioned the strength of evidence for SI joint injections when pooled across broad patient populations (Busse et al., BMJ, 2025). However, clinical practice guidelines from ASIPP, SIS, and other interventional pain societies continue to support SI joint injections in appropriately selected patients, particularly when a positive diagnostic block confirms the joint as the pain source. This underscores the importance of working with a physician trained in proper patient selection and image-guided technique.
What to Expect During the Procedure
Understanding what happens before, during, and after an SI joint injection can help reduce anxiety and prepare you for a smooth experience.
- Before the procedure. Your physician reviews your medical history, imaging studies, and prior treatments during an initial consultation. You may be asked to stop certain blood-thinning medications several days beforehand. Plan to have someone drive you home after the procedure if sedation is used.
- During the procedure. You lie face down on a procedure table. Your physician cleans and numbs the skin over the SI joint with a local anesthetic. Using fluoroscopic guidance, a thin needle is advanced into the SI joint. Contrast dye confirms correct needle placement before the medication is delivered. The entire procedure typically takes 15 to 30 minutes.
- After the procedure. You rest briefly in the recovery area and are monitored before being discharged the same day. Most patients are able to walk out of the office shortly after the injection. Mild sedation is available for patients who experience anxiety about needle-based procedures.
Recovery and Results
Most patients return to light daily activities the same day or the day after their SI joint injection. There is no extended recovery period, though your physician may recommend avoiding heavy lifting and strenuous exercise for 24 to 48 hours. In winter months, plan ahead for snow and ice at home entryways to reduce fall risk during the first 24 to 48 hours.
What to expect in the days following the injection:
- Day of the procedure: You may experience immediate pain relief from the local anesthetic. This temporary relief often fades within a few hours as the anesthetic wears off.
- Days 1 to 3: A mild post-injection flare, including temporary soreness at the injection site, is common and normal. Ice and over-the-counter pain medication can help manage this discomfort.
- Days 3 to 7: The corticosteroid begins to take full effect, and many patients notice a meaningful reduction in their SI joint pain.
How long does relief last? A prospective study found that patients receiving SI joint corticosteroid injections experienced significant pain reduction from a baseline VAS score of 5.85 to 3.00 at six months, with improvement in both physical examination findings and functional outcomes (Ab Aziz et al., Cureus, 2022). A comprehensive review by the World Institute of Pain documented pain relief lasting three months or longer for many patients (Szadek et al., Pain Practice, 2023).
Individual results vary based on the underlying cause, severity of joint inflammation, and overall health. When pain relief begins to fade, repeat injections or alternative treatments such as radiofrequency ablation may be discussed with your physician.
Risks and Side Effects
SI joint injections are considered a low-risk procedure. A systematic review evaluating safety across more than 1,300 patients found only 29 adverse events and 3 serious adverse events, confirming a favorable safety profile for image-guided sacroiliac joint interventions (Lee et al., Interventional Pain Medicine, 2023).
Common side effects (typically resolve within 1 to 2 weeks):
- Mild soreness or discomfort at the injection site
- Temporary numbness near the treated area
- Minor bruising or swelling
Rare side effects:
- Infection at the needle insertion site
- Prolonged numbness or temporary nerve irritation
- Allergic reaction to the anesthetic or contrast dye
- Temporary increase in blood sugar (relevant for patients with diabetes)
Your physician will discuss your complete medical history, including any medications or allergies, before recommending an SI joint injection.
When SI Joint Injections Are Not Enough
For some patients, SI joint injections provide significant but temporary relief that fades over time. When that happens, the pain management team evaluates the next step in a structured treatment pathway that progresses from least invasive to most invasive.
Radiofrequency ablation (RFA) is the most common next step after SI joint injections. This procedure uses controlled heat to disrupt the lateral branch nerves that transmit pain signals from the SI joint. A diagnostic lateral branch block is performed first to confirm which nerves are involved. A systematic review and meta-analysis found radiofrequency ablation effective for managing sacroiliac joint pain, with pain relief sustained at 6 to 12 months in many patients (Janapala et al., Current Pain and Headache Reports, 2024). Learn more about radiofrequency ablation at the Lawrenceville-area practice.
Additional options for patients with persistent SI joint pain include:
- Platelet-rich plasma (PRP) therapy, an emerging biologic treatment that uses your own blood components to support joint healing
- Physical therapy focused on pelvic stabilization, core strengthening, and targeted stretching
- SI joint fusion surgery, considered only for severe, refractory cases that have not responded to multiple rounds of conservative and interventional treatment (Horton et al., JBJS, 2024)
The treatment approach at Performance Pain and Sports Medicine follows the principle of exhausting less invasive options before considering surgical alternatives. An expert review on treatment sequencing for SI joint pain supports this stepwise approach, progressing from conservative management through interventional procedures based on each patient’s response (Cocconi et al., Expert Review of Neurotherapeutics, 2024). For patients whose pain proves to be discogenic rather than SI-related, an epidural steroid injection may be the more appropriate next step. For select discogenic candidates who want to avoid spinal fusion, Dr. Wiederholz can also discuss the Discseel® procedure performed at the Lawrenceville office.
Cost and Insurance
SI joint injections are typically covered by most major insurance plans when deemed medically necessary, including Medicare and New Jersey workers’ compensation. Coverage may require prior authorization, and many plans require documentation that conservative treatments (physical therapy, anti-inflammatory medication) have not provided adequate relief. The cost depends on insurance coverage, whether a diagnostic block alone or a therapeutic injection with corticosteroid is performed, and whether sedation is used.
The Lawrenceville-area office accepts most major commercial insurance plans, Medicare, and New Jersey workers’ compensation, and routinely handles documentation for injuries sustained at Bristol Myers Squibb, ETS, healthcare systems across Mercer County, and tri-state contracting employers. The office team can verify your specific insurance coverage and discuss any out-of-pocket costs before your appointment. For coverage questions, call 609-588-8600.
SI Joint Injections at Our Lawrenceville Office
Performance Pain and Sports Medicine performs SI joint injections at the Lawrenceville-area office at 3705 Quakerbridge Road, Suite 206, Hamilton, NJ 08619. The office sits on the Quakerbridge Road corridor that runs through both Lawrence and Hamilton townships, just off Route 1, making it easy to reach from Lawrenceville, Princeton, Princeton Junction, Pennington, Hopewell, Hamilton Square, Ewing, Plainsboro, Robbinsville, East Windsor, Hightstown, Cranbury, Trenton, and from Bucks County, PA, including Yardley and Newtown.
Dr. Matthias Wiederholz, MD, the physician at the Lawrenceville-area office, is quadruple board-certified in Physical Medicine and Rehabilitation, Pain Medicine, Sports Medicine, and Anti-Aging, Regenerative and Functional Medicine. He founded Performance Pain and Sports Medicine in 2009 and is a Master Discseel® Instructor, having been the first physician to bring the Discseel® procedure to New Jersey. Dr. Wiederholz performs every SI joint injection personally, under live fluoroscopic guidance, with continuity of care from initial evaluation through follow-up treatment. Jade Nemeth, PA-C supports patients throughout evaluation, treatment, and follow-up care.
The Lawrenceville patient population reflects the unique professional and demographic profile of the Princeton corridor. Bristol Myers Squibb research scientists, ETS staff, attorneys and finance professionals commuting on the Northeast Corridor line, Lawrenceville School and Rider University faculty, healthcare workers at Penn Medicine Princeton and Capital Health, and active-adult retirees throughout Mercer County and Hunterdon County all present with chronic lower back and buttock pain that has not responded to standard care. The office accepts most major commercial insurance, Medicare, and New Jersey workers’ compensation. It routinely handles referrals from Penn Medicine Princeton Medical Center, Capital Health Hopewell, Capital Health Regional in Trenton, RWJBarnabas / RWJUH Hamilton, St. Francis Medical Center, and primary care providers across central New Jersey.
In addition to SI joint injections and the full interventional pain management portfolio, the Lawrenceville office is one of the few practices in New Jersey performing the Discseel® procedure, an FDA-approved injectable biologic treatment for patients with chronic discogenic back pain who have failed conservative care and want to avoid spinal fusion. Dr. Wiederholz personally trains other physicians in the Discseel® technique.
What sets the Lawrenceville-area practice apart:
- A quadruple board-certified, fellowship-trained interventional pain specialist performing every procedure
- Fluoroscopic guidance for all SI joint injections
- Comprehensive diagnostic evaluation before recommending any intervention
- A complete treatment pathway from injections through radiofrequency ablation, plus Discseel® for select discogenic cases
- Most major insurance plans, Medicare, and New Jersey workers’ compensation accepted
To schedule an evaluation, call the Lawrenceville-area office at 609-588-8600 or contact us online. SI joint injections are also available at the Houston, League City, and Baytown Performance Pain locations.
Performance Pain and Sports Medicine
Address: 3705 Quakerbridge Road, Suite 206, Hamilton, NJ 08619
Landmark: On the Quakerbridge Road corridor, just off Route 1
Major Cross Streets: Quakerbridge Road, between Lawrence and Hamilton townships
Parking: On-site parking available
Phone: 609-588-8600
Frequently Asked Questions
Is the SI joint injection procedure available in Lawrenceville, NJ?
Yes. Sacroiliac joint injections are performed at the Lawrenceville-area office on Quakerbridge Road by Dr. Matthias Wiederholz, MD. All procedures use live fluoroscopic guidance and are completed as outpatient visits, with most patients leaving the office within 30 to 45 minutes of the injection.
Do you accept workers' compensation for pharma, healthcare, or contractor injuries?
Yes. The Lawrenceville office accepts New Jersey workers’ compensation and routinely treats injured workers from Bristol Myers Squibb, ETS, healthcare systems across Mercer County, and tri-state contracting employers. The office handles documentation and authorization directly with carriers.
Do you accept referrals from Penn Medicine Princeton, Capital Health, and RWJBarnabas?
Yes. The Lawrenceville office accepts referrals from Penn Medicine Princeton Medical Center, Capital Health, RWJBarnabas, and primary care providers across central New Jersey, Bucks County PA, and the surrounding tri-state area. Self-referral is also accepted for most insurance plans.
Do patients travel to Lawrenceville from Pennsylvania or New York for these procedures?
Yes. Patients commonly travel to the Lawrenceville office from Bucks County, PA, Mercer County, and the broader tri-state area for both SI joint injections and the Discseel® procedure performed by Dr. Wiederholz.
How painful are SI joint injections?
Most patients tolerate the procedure well. The physician applies a local anesthetic to numb the skin and tissue before inserting the needle, which significantly reduces discomfort. You may feel brief pressure or a dull ache as the needle reaches the joint. Mild sedation is available for patients who are anxious about the procedure.
Do you get put to sleep for an SI joint injection?
General anesthesia is not required. SI joint injections are performed under local anesthesia, meaning you remain awake throughout the procedure. Light sedation (such as IV sedation) is available if needed, but most patients do not require it. The procedure typically takes 15 to 30 minutes.
What should you not do after an SI joint injection?
Avoid heavy lifting, strenuous exercise, and soaking in a bath or pool for 24 to 48 hours after the injection. You should also avoid driving on the day of the procedure if sedation is used. Light walking and normal daily activities are generally safe to resume the same day.
How long does an SI joint injection last?
Pain relief duration varies by patient. Many patients experience meaningful relief lasting several weeks to several months. A prospective study documented significant pain reduction maintained at six months for patients receiving corticosteroid SI joint injections. When relief fades, the injection can often be repeated or your physician may recommend radiofrequency ablation for longer-lasting results.
How much does an SI joint injection cost?
The cost of an SI joint injection depends on your insurance plan, whether a facility fee applies, and the specific medications used. Many insurance plans cover SI joint injections when a diagnostic block has confirmed the joint as the pain source and conservative treatments have been tried. Contact the Lawrenceville-area office at 609-588-8600 to discuss coverage and out-of-pocket costs before scheduling.
What if my SI joint injection does not work?
A negative result is still clinically useful. It indicates the SI joint is likely not the primary pain source, allowing Dr. Wiederholz to redirect diagnostic efforts toward other potential causes, including evaluation for discogenic pain that may be a candidate for the Discseel® procedure or for an epidural steroid injection.
Does insurance cover SI joint injections in New Jersey?
Most major insurance plans, Medicare, and New Jersey workers’ compensation cover medically necessary SI joint injections. Prior authorization is often required. The Lawrenceville office team verifies coverage before scheduling.
Schedule Your SI Joint Injection Consultation in Lawrenceville
If you are living with chronic lower back or buttock pain that has not improved with rest, physical therapy, or oral medications, the pain management team at Performance Pain and Sports Medicine can help determine whether an SI joint injection is appropriate for you. Contact the Lawrenceville-area office or call 609-588-8600 to schedule a consultation with Dr. Matthias Wiederholz, MD.
MEDICAL DISCLAIMER
This article is for educational purposes only and does not replace professional medical advice, diagnosis, or treatment. The information presented reflects an interventional pain management perspective and is intended to support, not substitute, your relationship with a qualified healthcare provider. Individual results vary based on diagnosis, pain duration, overall health, and response to treatment. Some procedures may not be covered by insurance. Treatment outcomes depend on proper patient selection and accurate diagnosis. Always consult a board-certified physician before pursuing any pain management treatment.
Medically reviewed by Dr. Matthias Wiederholz, MD · Performance Pain and Sports Medicine · Last reviewed: May 2026
Medically reviewed by Matthias Wiederholz, MD
Board-Certified in Physical Medicine & Rehabilitation, Pain Medicine, Sports Medicine, and Anti-Aging, Regenerative and Functional Medicine
Last reviewed: May 2026
