Types of Tendinitis:
Nine Sites, One Technology.

July 2026 · 10 min read · Clinical Guide

Tendinitis vs. Tendinosis vs. Tendinopathy: The Clinical Distinction

The terminology matters for treatment selection. Tendinitis (or tendonitis) denotes inflammatory pathology — typically acute, with histological evidence of neutrophil and macrophage infiltration, prostaglandin E2 elevation, and edema. Tendinosis is a degenerative condition — chronic, without inflammatory cells, characterized by collagen fiber disorganization, mucoid change, and neovascularization (Haglund deformity is a classic example). Tendinopathy is the umbrella term used when the exact pathological mechanism is unclear — which is the case in most clinical presentations.

PEMF addresses both subtypes via distinct mechanisms: in acute tendinitis, the anti-inflammatory pathway (cytokine suppression, edema reduction) dominates; in tendinosis, the collagen fiber remodeling and growth factor upregulation pathway (TGF-β, IGF-1, VEGF) drives the benefit. The 2026 Frontiers systematic review (PMC12916110) confirms PEMF efficacy across both mechanistic subtypes.

The Nine Clinical Presentations

Tendinopathy is not a single condition — it is nine distinct clinical problems, each with its own anatomical specifics, loading pattern, and differential diagnosis. Below is a clinical classification by site:

How PEMF Works on Tendon Tissue

Three mechanisms operate in parallel across all tendinopathy types:

1. Anti-inflammatory phase (sessions 1–3): Suppression of IL-1β, TNF-α, and prostaglandin E2 at the tendon–enthesis interface. This reduces pain during initial loading and allows earlier rehabilitation exercise.
2. Collagen synthesis phase (sessions 4–8): Upregulation of TGF-β and IGF-1 stimulates type I collagen production by tenocytes. In vivo histological confirmation (PMC7093940) shows measurable fiber realignment at this stage.
3. Remodeling phase (sessions 9–12+): VEGF-driven neovascularization of previously avascular repair tissue improves oxygen and nutrient supply to the regenerating tendon. PEMF at 75–100 Hz in this phase accelerates load-bearing capacity restoration.

Critically, PEMF is hands-free during the 20–40 minute session — the clinician can simultaneously perform manual therapy or supervised exercise, increasing per-session revenue and therapeutic yield.

PEMF Protocol Parameters by Anatomical Site

PEMF vs. Competing Treatments for Tendinopathy

The Philippine Tendinopathy Market

The Philippines has a disproportionately large tendinopathy burden driven by three population segments:

• BPO workforce (1.3 million workers): Prolonged keyboard and mouse use causes de Quervain's tenosynovitis, lateral epicondylitis, and shoulder impingement at rates 2–3× the general population. High income, health-conscious, treatment-adherent.
• Sports-active population (5.5 million recreational athletes): Basketball (most popular sport), volleyball, and running generate high patellar, Achilles, and peroneal tendinopathy rates. Return-to-sport is the primary outcome valued by this group.
• Healthcare workers and domestic workers (nursing, retail, food service): Prolonged standing causes tibialis posterior and Achilles pathology. The Philippines exports over 1 million healthcare workers annually — the local nursing population is enormous.

Combined, these segments represent an estimated 800,000–1,200,000 tendinopathy presentations annually in Metro Manila and Cebu alone — of which fewer than 15% access evidence-based physiotherapy.

Who Is PEMF Most Appropriate For?

PEMF for tendinopathy is most appropriate when:

• Symptoms have persisted beyond 4 weeks despite rest and NSAIDs
• Corticosteroid injection has been refused, failed, or maxed out (3 injections per site)
• The patient cannot tolerate the pain of shockwave therapy
• Return-to-sport or return-to-work timeline is critical (PEMF allows concurrent loading exercise)
• The patient requires hands-off treatment during a co-morbid physiotherapy session

Contraindications: active pacemaker; pregnancy; active malignancy in treatment area. No age minimum documented in the literature.

Frequently Asked Questions

Can PEMF replace eccentric loading exercises for Achilles tendinopathy?

No. Eccentric loading (the Alfredson protocol) remains the cornerstone treatment for mid-portion Achilles tendinopathy with the strongest long-term evidence. PEMF's role is to accelerate the anti-inflammatory phase and support collagen remodeling concurrently — allowing earlier and more comfortable eccentric loading, not replacing it.

Is one PEMF device sufficient for all nine tendinopathy types?

Yes. Clinical PEMF systems include multiple coil geometries (flat pad, saddle, focal coil, wrap coil) and programmable frequency/intensity settings that cover all anatomical sites. The same device serves the full tendinopathy spectrum, maximizing utilization per unit in a multi-specialty clinic.

How many sessions until a patient notices improvement?

Most patients report reduced pain after sessions 3–4 (anti-inflammatory phase). Structural improvement (collagen remodeling, VEGF-driven repair) is not clinically apparent until sessions 8–10 but is the outcome that prevents recurrence. Clinics should educate patients on the two-phase timeline to manage expectations and prevent early dropout.