What is Extracorporeal Shockwave Therapy — Non-Surgical Treatment that Promotes Tissue Recovery Using Acoustic Energy
You've been taking medications and doing physical therapy for months, but your heel, Achilles tendon, front of your knee, and shoulder still ache. At this point, you're deeply contemplating what treatment to pursue next. Extracorporeal Shockwave Therapy (ESWT) is a non-surgical treatment frequently chosen at this stage. Unlike pain medications that temporarily mask pain, it can stimulate the recovery process of damaged tendon and fascia tissue itself. This is where it differs from other treatments.
Extracorporeal shockwave delivers high-energy acoustic waves created outside the body to the affected area. When gel is applied to the skin and the handpiece is placed, strong pressure waves briefly penetrate deep into the tissue. This provides micro-stimulation to chronically degenerated tendons, calcified areas, and thickened fascia. It can be received at outpatient clinics without incisions or drug injections, and each treatment session takes 10-20 minutes depending on the area.
When acoustic energy reaches the tissue, new blood vessels may begin to grow. It can trigger the production of collagen, a tissue protein, and inflammatory signaling substances may subside. As these changes overlap, tissue may begin to heal again. The essence of chronic tendinopathy is "tendon tissue that has degenerated without healing." Simply masking pain signals with pain medications leaves the tissue unchanged. Extracorporeal shockwave is a treatment that may reawaken the recovery process that had been stagnant.
Evidence is gradually accumulating for using ESWT in musculoskeletal pain that has not sufficiently improved with medications and physical therapy.(Schroeder Allison N et al., 2021) If you expect pain to disappear immediately after the procedure, you may be disappointed. Since the goal is tissue reconstruction rather than pain relief, the response doesn't appear immediately. It appears slowly over 4 weeks at the shortest, up to 12 weeks. Understanding that there is such a time lag between treatment and response is necessary to gauge what to expect when starting treatment.
What Types of Pain Can It Be Used For?
Extracorporeal shockwave is not a treatment recommended equally for all types of pain. There are specific indications with substantial clinical evidence, and outside of those, it remains as a supportive measure. Knowing which category your diagnosis falls into can help you gauge what to expect.
Plantar Fasciitis
The indication with the most solid evidence is plantar fasciitis. This is a condition where the inner part of the heel has sharp pain on the first step in the morning. In analyses combining multiple clinical studies, ESWT showed significant effects on both short-term and long-term pain and function in plantar fasciitis. Conversely, in patellar tendinitis and Achilles tendinitis, pain and functional improvement effects compared to placebo were minimal.(Charles Ravon et al., 2023) There are individual differences in treatment response. All three conditions share the commonality of being chronic tendinopathies that have been dragging on for months to as long as a year or more. Responses tend to be better in chronically degenerated tissue rather than acute injuries.
Shoulder Rotator Cuff Tendinopathy
The shoulder is also important. Rotator cuff tendinopathy, particularly calcific tendinitis (a condition where calcium deposits harden in the shoulder tendons), is the area where extracorporeal shockwave is most frequently used. Analysis of rotator cuff tendinopathy studies consistently showed results of reduced pain and improved shoulder function.(Xue Xiali et al., 2024) When calcium deposits are present, there are reports that shockwaves may be involved in helping the body absorb the calcium.
Indication Criteria
It's difficult to recommend it equally for all shoulder pain or all foot pain. When there are large rotator cuff tears, radicular pain due to nerve root compression, or severe swelling in the acute period immediately after trauma, ESWT is not the first priority. Diagnosis comes first. When ultrasound or MRI confirms the nature of the lesion, and chronic tendinopathy, calcification, or fascia degeneration is determined to be the main cause of pain, extracorporeal shockwave becomes appropriate to consider.
The criterion for indication is chronic tendinopathy that has been slow to respond to conservative treatment for more than 3 months. For pain that meets this condition, ESWT becomes a reasonable next option.
Focal and Radial Types — Different Equipment is Suitable Depending on Lesion Depth
Extracorporeal shockwave actually involves two types of equipment used together. Focal and Radial. Both are called shockwave, but the way energy spreads within tissue is different.
Focal — Deep and Localized Targeting
Focal type concentrates acoustic energy at one point at a specific depth. It's designed so energy concentrates in a narrow area several centimeters deep under the skin, and the focal depth is adjusted according to the equipment. It's advantageous for precisely delivering energy to deep, localized lesions like calcium deposits in the shoulder rotator cuff or degenerative changes at the Achilles tendon insertion. When pain is clearly localized to one point and imaging studies also show degeneration or calcification in that location, the advantages of focal type become evident.
Radial — Wide and Shallow Area
Radial type is different. Energy starting from the tip of the handpiece spreads in a fan shape from the surface and gradually weakens. It's a method that provides stimulation to a wide, shallow area rather than one deep point. It's suitable when releasing overall load from the plantar fascia, or addressing tension in calf or thigh fascia, or stimulation of superficial tendons. Pain during the procedure is also more distributed than with focal type, reducing patient burden.
Equipment Selection
Equipment selection is not a matter of "which is better" but "which is right for this lesion."(Schroeder Allison N et al., 2021) When dealing with clear targets in deep locations like shoulder calcific tendinitis, focal type takes priority. When trying to distribute tension across the entire plantar fascia, radial type is more appropriate. The two methods are not mutually exclusive, so it's common to use both on the same patient. In chronic plantar fasciitis, if local degeneration at the calcaneal insertion is prominent, that area might be treated with focal type while the overall fascia is treated with radial type.
How Many Treatments Are Needed for Improvement — The 4-12 Week Timeline
"How many treatments do I need?" This is the most frequently asked question in the clinic. While there isn't a single definitive answer, there is a clear general framework. Energy flux density, number of shocks, shockwave type (focal or radial), frequency and timing of sessions, application site, and post-treatment schedule are all factors adjusted in the clinical environment. For most indications, optimal treatment schedules have not yet been established.(Schroeder Allison N et al., 2021)
Sessions and Response Time Lag
An important point is that the time when sessions end and when responses appear are different. Immediately after treatment, pain may not change significantly, or the treatment site may actually throb for several days. This brief change in pain is part of the process of tissue responding to stimulation. Being more painful for a few days doesn't mean the treatment went wrong, but rather signals that the dormant recovery response is awakening.
Actual pain relief is often felt starting around 4-6 weeks after treatment completion, and structural changes at the tissue level can continue for 8-12 weeks. In other words, the evaluation standard is one to two months later, not immediately after the procedure.(Charles Ravon et al., 2023) Without knowing this in advance, it's easy to discontinue treatment midway. While response curves vary from person to person, just because there's no immediate change after treatment doesn't mean it should be judged as a failure.
Stopping planned sessions midway means stimulation is cut off before sufficient tissue response can occur. It's like turning off the switch before the recovery curve can take off, making it difficult to expect the same level of response. Rather than making decisions based only on how you feel after the first 1-2 sessions, it's more reasonable to complete the planned 5 sessions or so and observe the changes over 4-12 weeks together.
Daily Management Must Go Hand in Hand
Post-treatment daily management also affects outcomes. For plantar fasciitis, calf and plantar fascia stretching and shoe correction should be included; for Achilles and patellar tendinitis, progressive loading exercises; for shoulder calcific tendinitis, shoulder blade stabilization exercises must accompany treatment so that the recovery response awakened by shockwave can lead to actual functional improvement. Treatment alone is only half the equation. The patient's daily life creates the other half.
For chronic tendinopathies where recovery has been slow with medications and physical therapy, extracorporeal shockwave is a treatment that can be considered at the pre-surgical stage. When you understand the indications, equipment characteristics, and the 4-12 week timeline together, you can create a realistic treatment plan.
This article is intended to provide medical information. Since it may vary depending on individual conditions, please consult with a specialist for accurate diagnosis and treatment.
References
- Schroeder Allison N, Tenforde Adam S, Jelsing Elena J (2021). Extracorporeal Shockwave Therapy in the Management of Sports Medicine Injuries. Curr Sports Med Rep. PMID: 34099607
- Charles Ravon, Fang Lei, Zhu Ranran (2023). The effectiveness of shockwave therapy on patellar tendinopathy, Achilles tendinopathy, and plantar fasciitis: a systematic review and meta-analysis. Front Immunol. PMID: 37662911
- Xue Xiali, Song Qingfa, Yang Xinwei (2024). Effect of extracorporeal shockwave therapy for rotator cuff tendinopathy: a systematic review and meta-analysis. BMC Musculoskelet Disord. PMID: 38704572
Frequently Asked Questions
How much pain is there during the procedure?
During the procedure, there may be strong pressure or tingling sensations in the affected area, and the intensity varies depending on pain sensitivity and lesion depth. The practitioner gradually increases the energy level, so if the pain becomes unbearable, please inform them immediately. The output can be adjusted.
Which is better between focal and radial types?
Which equipment is more suitable is determined by the depth and location of the lesion. Rather than patients choosing for themselves, it's the principle for medical staff to make the judgment based on imaging test results. Schedules using both devices together are also common in clinical practice, so prescriptions considering both diagnostic findings and symptom patterns are necessary.
Can I receive extracorporeal shockwave instead of surgery?
Extracorporeal shockwave has recognized evidence as a non-surgical treatment at the pre-surgical stage for chronic tendinopathies that remain slow to recover even after medications and physical therapy. However, when tendon rupture is involved or structural damage is severe, surgical treatment may be necessary, so treatment direction should be decided based on detailed examination results.
Are there contraindications for extracorporeal shockwave treatment?
Blood coagulation disorders or taking anticoagulants, presence of malignant tumors at the treatment site, areas adjacent to growth plates in children and adolescents whose growth plates haven't closed are generally classified as contraindications. During pregnancy or when there is infection or skin damage at the treatment site, you must inform the medical staff before treatment.
When can I exercise after treatment?
On the day of treatment, the treatment site may temporarily throb or swell, so it's good to avoid vigorous exercise. Light activities like walking can usually be done from the same day, but recovery speed varies from person to person, so the timing of returning to exercise should be determined in consultation with medical staff for safety.