Steroid injections for plantar fasciitis are a complex mix of good and bad news

Steroid (cortisone) injections and iontophoresis (injection without a needle, using a small electric charge to drive a drug through the skin) are routinely prescribed by physicians for plantar fasciitis, and many other inflammatory conditions. They are often regarded as something of a magic bullet for inflammation, and not without good reason: cortisone has powerful anti-inflammatory properties, and it certainly has the potential to dramatically reduce pain, especially in the short term.

Steroid injections are certainly not an unreasonable treatment option for plantar fasciitis, especially for a stubborn case. And yet, as with many other popular therapies, there is shockingly little science to back it up, and there are also some concerns.

Only two proper scientific tests of steroid injections have ever been done, in 1997 and 1999. Both found the same results: steroid injections were helpful in the short term only.

Cortisone has powerful anti-inflammatory properties, and it certainly has the potential to dramatically reduce pain, especially in the short term.

What about the science since then? A decade has gone by — surely there’s more and better research by now? Unfortunately, no: we’re still waiting for that. All the studies done in the last ten years, about one a year — Yucel, Tsai, Frater are three recent examples — have not been serious attempts to show the efficacy of steroid injections, but instead have focussed on peripheral issues like what kind of injection-guiding technology works best. It’s all worthwhile stuff, but fairly useless in terms of finding out if steroid injections “really work.” They offer something like “circumstantial evidence” in a courtroom — it’s suggestive, but it’s not proof.

So, although there’s little doubt that they really do relieve at least some pain in the short term, it’s still a wide open question about lasting benefit. Can steroid injections alone solve plantar fasciitis? Nobody knows, but it seems unlikely. A comprehensive The Cochrane Collaboration review of the science in 2003 discouragingly concluded:

Steroid injections are a popular method of treating the condition but only seem to be useful in the short term and only to a small degree.

And there’s danger! No injection of anything can be completely safe, and cortisone in particular — especially in this location — has the potential to do as much harm as good. Cortisone’s best-known problem is that it “eats” connective tissue with overuse, which can be bad news for any anatomy, but especially an anatomical structure like the plantar fascia, which is a high-performance piece of tissue, and already strained to its limit by definition in every case of plantar fasciitis, especially the bad cases. Plantar fascia rupture (yikes!) is one of the risks of steroid injection. Tatli et al describe a few other possible complications:

• the destruction of your natural heel cushion (plantar fat pad atrophy)
• direct nerve injury from the injection (lateral plantar nerve, see Snow)
• a bone infection (calcaneal osteomyelitis, see Gidumal)
• burning of the underlying skin (only from iontophoresis), which is the least of these complications, but still rather undesirable in a situation where burning pain is already a major problem!

Your odds of avoiding these complications are good, but the stakes are high. They probably won’t happen, but it’s really bad news if they do. They can make a bad case of plantar fasciitis even worse, even permanent: “Fascial rupture and fat pad atrophy are especially serious complications as they can lead to intractable complications” (Tatli). If you thought you had a stubborn case of plantar fasciitis now, wait until you’re in that boat.

Given the known and plausible risks, you should never consider a cortisone injection until the virtually risk-free options discussed so far have already been tried. But let’s keep this in perspective: although the dangers are certainly real, they are not great, and they are probably well worth risking, especially if you’re already a mess and have nothing to lose.

Steroid injection in moderation may be a great way to reduce the pain in the short term, while other therapies take care of the longer term. My recommendations:

• Discuss it with your doctor and make sure that he or she shows an appropriate level of concern about complications. Avoid accepting steroid injections from a physician who seems to think it’s a magic bullet — that’s never a constructive attitude.
• Only use steroid injections in moderation — probably no more than three injections. Use it only to manage pain in the short term while other, safer therapies are also being pursued.
• Avoid steroid injections if you have any sign of the complications, or if you develop them after any injection.