Tenex and TenJet: minimally invasive treatment for stubborn plantar fasciitis and Achilles tendinitis

Most heel pain and Achilles pain gets better with stretching, strengthening, the right shoes and time. But not all of it. In a Danish study of 174 people with plantar fasciitis, half still had symptoms five years after it started.^[9] In another study, a 12-week calf-strengthening program worked for 89% of painful Achilles tendons in the middle of the tendon, but only 32% where the tendon meets the heel bone.^[10] For those people, months of stretching and night splints can feel like a dead end. Minimally invasive tenotomy is designed for exactly that group.

What Tenex and TenJet do

In long-standing plantar fasciitis and Achilles tendinopathy, part of the tissue has degenerated. These procedures find that damaged area with ultrasound and remove it, so the healthy tissue around it can heal.^[3,8]

• Tenex passes a needle-sized tip through a cut of about 5 mm, after local anesthetic. The tip vibrates at an ultrasonic frequency, breaking up the damaged tissue and suctioning it away while the surgeon watches on the ultrasound screen.^[3,4]
• TenJet works through a similar small incision under ultrasound. A high-pressure stream of saline runs inside the tip, cutting the damaged tissue and carrying it away; the skin is closed with adhesive strips.^[5] In a laboratory study on cow tendon with chemically induced damage, it removed the damaged tissue with negligible disruption of the healthy tissue around it.^[11]

There’s no large incision, no general anesthesia and, in one series, no opioid prescriptions.^[3] Patients typically wear a walking boot for one to two weeks.^[7]

Results for plantar fasciitis

The studies of ultrasonic treatment for the plantar fascia report large, lasting drops in pain:

• Mayo Clinic, six years on. 58 procedures, after symptoms lasting about two years on average: pain fell from 6.8 to 0.7 out of 10; 91% of treated feet were rated satisfied and 90% would recommend it, with no complications.^[6]
• A prospective study of 67 patients. Pain improved by almost 6 points out of 10, and 94% were satisfied at three months and at one year, with no complications.^[12]
• A multicenter study of 56 patients followed for a little over two years found significant gains in pain, physical function and mobility.^[13]
• When surgery had already failed. In a small early series of 12 patients, four had already had an open or endoscopic release that didn’t work; all 12 were essentially pain-free at two years.^[14]

Results for Achilles tendinitis

• Insertional tendinopathy (pain where the tendon meets the heel bone, the type exercise helps less): in 34 patients, the share with moderate or severe pain fell from 68% to 15% at a median of 1.7 years, and all 14 patients whose work status was recorded were back at work by 12 weeks.^[3] In another series of 25 patients (26 procedures), 84.6% had a successful result, including two who needed a second procedure.^[15]
• A prospective study of 56 patients with insertional or midportion tendinopathy found function improved by 25 points at one year, about three times the smallest change patients notice. Most were cleared for full activity by three to four months. Of the 39 who answered, about three-quarters rated the result ideal or satisfactory, though about half still considered their symptoms not yet acceptable.^[2]

That study also showed who does less well: people with a prominent heel bump (Haglund’s deformity) or calcium deposits in the tendon improved less.^[2] In our view, an open operation that removes the bump is often the better choice for them. See Haglund’s deformity.

How it compares with open surgery

Open surgery works well for many people, but it is a bigger undertaking:

• Insertional Achilles surgery. In a review of 465 operations, 89.6% had good or excellent results, but the average complication rate was 18.3%.^[16]
• Midportion Achilles surgery. Complications were 5.3% with minimally invasive approaches versus 10.5% with open ones, a trend rather than a statistically firm difference, and some older open-surgery protocols used a cast for more than six weeks.^[17]
• Plantar fascia release. Complications averaged 5% with the endoscopic approach and 11% with open surgery.^[18]
• Ultrasonic tenotomy. 2 complications in 289 procedures (0.7%) across elbow, knee, Achilles and plantar fascia treatments: one superficial wound infection and one area of skin sensitivity. Rare serious problems, including Achilles tendon rupture and a blood clot, have been reported in other small series.^[7] In the insertional Achilles series, 70% were satisfied at 6 to 12 weeks.^[3]

These figures come from different studies of different patients, not head-to-head trials, so they show the general picture rather than a precise comparison.

What the evidence can’t tell us yet

We want you to decide with the full picture:

• No randomized trials yet. None of the foot and ankle studies has a comparison group, and reviews call for controlled trials.^[8,19] When the American College of Foot and Ankle Surgeons reviewed heel pain treatments in 2018, it rated ultrasonic debridement “uncertain” because adequate peer-reviewed studies weren’t yet available; most of the results above were published after that.^[1]
• TenJet’s published results come from other tendons. No study of TenJet met the criteria of a 2025 systematic review,^[8] and its published patient results so far come from other parts of the body, such as the elbow and hip. For the heel and Achilles, its use rests on the same principle as Tenex.
• Industry ties. Some of the researchers above have consulted for or advised the company that makes Tenex.^[14,3,7]
• Insurance. Some insurers still classify the procedure as investigational and don’t cover it,^[20] so we check your benefits before scheduling.

Who it suits

You may be a candidate if:

• Pain has lasted six months or more despite well-run non-surgical care. That’s the point at which the American College of Foot and Ankle Surgeons says surgery can be considered for heel pain.^[1]
• Ultrasound shows a thickened, damaged area of the plantar fascia or Achilles tendon that can be targeted.
• You want to avoid, or postpone, a larger open operation.

It is less suited to a large heel bump or heavy calcification,^[2] to a tight calf, where calf lengthening may address the cause,^[1] and to heel pain from a pinched nerve. Our sister practice, the Lower Extremity Nerve Institute (external site), covers that last one.

What recovery looks like

• The first two weeks: a walking boot, then a gradual return to supportive shoes.^[7]
• From about two weeks: guided strengthening, with no heavy loading of the Achilles before six weeks.^[3]
• Results build over weeks. In the early plantar fascia series, pain eased between 5 and 13 weeks.^[14] After Achilles treatment, most patients were cleared for full activity by three to four months.^[2]

How we decide

Dr. Efe Ozturk is a Foot and Ankle Surgeon and podiatrist who offers both Tenex and TenJet. We confirm the diagnosis with an exam and in-office ultrasound, and make sure the non-surgical steps have had a fair trial: stretching and strengthening, footwear and orthotics, and shockwave therapy. If pain persists, we go through the options side by side: Tenex or TenJet, calf lengthening, or open surgery through our Center for Lower Extremity Surgery (external site). See our heel pain and Achilles tendon pages for the full range of care.

Common questions

Is Tenex surgery?

It’s a minimally invasive surgical procedure: it removes tissue through a small incision. It’s done under local anesthetic through a cut of about 5 mm, without general anesthesia.^[3]

Does it hurt?

The area is numbed first. In one Achilles series, no patient was prescribed opioid pain medicine afterward.^[3]

Can it be repeated?

Yes. In one Achilles series, two patients whose first procedure didn’t fully work did well after a second.^[15]

How is TenJet different from Tenex?

Both remove damaged tissue through a small incision under ultrasound. Tenex uses ultrasonic energy; TenJet uses a high-pressure saline jet.^[4,5] Tenex has more published foot and ankle results.^[8]

When to see a podiatrist