What does an ultrasound guided knee injection show?

What can the person treating me see?

The screen can show fluid, nearby tissue, and the needle tip as it moves. It also shows the joint space, the small gap inside the knee where medicine goes.

That view may help when the knee is hard to feel through the skin. It can also guide the needle when fluid needs to come out.

Without ultrasound, the provider feels your kneecap and joint line, then uses those firm points to guide the needle into the knee; this usual method is called landmark guidance. It isn't guesswork.

You may ask why one way suits your knee. A screen can't tell how much relief the medicine will bring.

Does better aim mean longer relief?

Ultrasound can help the needle reach the intended spot. Some people may feel relief sooner during the first several weeks.

Months later, people haven't clearly done better just because ultrasound was used. The medicine still has its own benefits, limits, and side effects.

A clear view can't make the wrong medicine right for your knee. You may ask what the screen will confirm and what to expect afterward.

What will the visit be like?

At the start, you'll describe where it hurts while a trained person examines the knee. That exam helps decide where a needle would enter.

You'll have time to mention blood thinners, diabetes, skin trouble, or a recent illness. These details may change the care offered that day.

Once the gel is on your skin, the small hand-held probe sends live images of the knee to the screen, so the person treating you can watch the needle as it enters. The probe stays outside your knee.

The person treating you watches the needle and checks for fluid that may need removal. Before leaving, you can ask what soreness is usual and when activity may begin again.

Sources

1. A systematic review of ultrasound versus anatomic (landmark) guidance found needle-placement accuracy was greater with ultrasound guidance at every anatomic site, and short-term (<6 weeks) symptom onset improved, but long-term outcomes were NOT shown to differ between the two techniques; the accuracy advantage was largest in small joints.

   Gilliland CA, et al. — Ultrasound versus anatomic guidance for intra-articular and periarticular injection: a systematic review.. Phys Sportsmed, 2011. DOI: 10.3810/psm.2011.09.1928.

2. A study using fluoroscopy as the reference standard confirmed that injectate placed into the suprapatellar recess under ultrasound guidance disperses into the tibiofemoral joint after a brief bout of walking, and that blinded radiologist review corroborated the interventionalist's reading of correct needle placement.

   Varlotta C, et al. — Accuracy of ultrasound-guided knee injections confirmed by fluoroscopy.. Interv Pain Med, 2023. DOI: 10.1016/j.inpm.2022.100174.

3. The HIT randomized trial (198 participants) found that adding a single ultrasound-guided triamcinolone-plus-lidocaine hip injection to best current treatment improved hip pain over six months (mean difference -1.43, 95% CI -2.15 to -0.72), but that the triamcinolone arm was NOT better than ultrasound-guided lidocaine alone; benefit was concentrated in patients with ultrasound-confirmed synovitis or effusion.

   Paskins Z, et al. — Clinical effectiveness of one ultrasound guided intra-articular corticosteroid and local anaesthetic injection in addition to advice and education for hip osteoarthritis (HIT trial): single blind, parallel group, three arm, randomised controlled trial.. BMJ, 2022. DOI: 10.1136/bmj-2021-068446.

4. A clinical review of peripheral joint injections frames them as a treatment for joint-mediated pain (arthritis, tendinopathy, bursitis) that has NOT responded to conservative management, and states plainly that these injections are typically not curative - their objective is to reduce pain enough to allow physical and pharmacologic rehabilitation to work.

   Marcolina A, et al. — Peripheral Joint Injections.. Phys Med Rehabil Clin N Am, 2022. DOI: 10.1016/j.pmr.2022.01.005.