The big toe that no longer bends

With every step we take, the big toe (hallux) needs to bend upward about 65 degrees during the propulsion phase — it is this movement that allows us to push the ground and move forward. When the metatarsophalangeal joint of the first toe loses mobility from cartilage degeneration, walking becomes painful. The patient begins to "roll" the weight onto the outer border of the foot, avoiding propulsion through the big toe, and develops an antalgic gait that overloads the knees and spine.

Hallux rigidus is osteoarthritis of the first metatarsophalangeal joint — the second most common arthritis of the foot, behind only ankle arthrosis. Unlike hallux valgus (bunion), which is a lateral deviation of the big toe, hallux rigidus is a progressive loss of motion with pain on dorsiflexion. Both conditions can coexist and aggravate each other. Periarticular acupuncture offers control of pain and local inflammation, improving functionality during gait.

How the big-toe joint degenerates

  1. Repetitive biomechanical overload

    The first metatarsophalangeal joint supports up to 40–60% of body weight during the propulsion phase of gait. Factors such as flatfoot, elevated first metatarsal (metatarsus primus elevatus), or inadequate footwear alter load distribution, accelerating wear of articular cartilage.

  2. Chondral degeneration and osteophyte formation

    Articular cartilage thins progressively, exposing the subchondral bone. In response, the body forms osteophytes (bone spurs) around the joint — especially on the dorsal surface, where they create a palpable prominence and mechanically block hallux dorsiflexion.

  3. Synovitis and periarticular inflammation

    The inflamed joint produces synovitis (inflammation of the synovial membrane) with edema and pain. Each step that forces dorsiflexion aggravates the inflammation, creating a cycle of pain-stiffness-compensation. The joint capsule progressively thickens, contributing to limited motion.

  4. Periarticular acupuncture

    Insertion of needles around the metatarsophalangeal joint (medial and lateral periarticular points, plus distal points such as LR-3 and SP-3) modulates local inflammation via neurogenic anti-inflammatory mechanisms. Low-frequency electroacupuncture promotes analgesia and may slow the progression of chronic synovitis.

Big-toe arthrosis in numbers

2.5%
OF THE ADULT POPULATION
is affected by symptomatic hallux rigidus — prevalence that increases significantly after age 50, reaching up to 10% in this age range
65°
OF DORSIFLEXION
is the normal range of motion of the hallux for functional gait — in grade II hallux rigidus, this range falls to less than 30 degrees, compromising propulsion
80%
BILATERAL
of hallux rigidus cases are bilateral (affect both feet), although frequently asymmetric — one side is more symptomatic than the other
60–70%
PAIN RELIEF
with a protocol of periarticular acupuncture and footwear modification in patients with hallux rigidus grades I and II — reducing the need for oral anti-inflammatories

Recognizing big-toe arthrosis

Critérios clínicos
06 itens

Clinical pattern of hallux rigidus

  1. 01

    Pain in the big toe when walking, especially in the propulsion phase

  2. 02

    Progressive joint stiffness — difficulty bending the big toe upward

  3. 03

    Palpable bony prominence on the dorsum of the joint (dorsal osteophyte)

  4. 04

    Pain when wearing rigid or heeled footwear — pressure over the osteophyte

  5. 05

    Pain when squatting or standing on tiptoe

  6. 06

    Compensatory gait — weight shifted to the lateral border of the foot

Myths and facts about big-toe pain

Myth vs. Fact

MYTH

All big-toe pain is a bunion

FACT

A bunion (hallux valgus) is the visible lateral deviation of the big toe with medial prominence. Hallux rigidus is an arthrosis of the joint with loss of motion and dorsal osteophyte. Clinical distinction is simple: in a bunion, the big toe deviates outward; in rigidus, the big toe does not bend upward. The two can coexist, but treatment of each component is different.

MYTH

Sudden, intense big-toe pain is arthrosis

FACT

Sudden pain with intense redness, swelling, and warmth in the big toe — especially at night — is the classic pattern of gouty arthritis (gout), not arthrosis. Gout is a treatable rheumatologic emergency that requires uric acid measurement and specific treatment. Arthrosis has insidious onset and progressive, not acute, pain. The physician differentiates the two conditions by the temporal pattern and the exam.

MYTH

Hallux rigidus is only resolved with surgery

FACT

Surgery (cheilectomy or arthrodesis) is reserved for advanced grades with failure of conservative treatment. In grades I and II, footwear modification (rigid "rocker bottom" sole that reduces the need for dorsiflexion), periarticular acupuncture for pain control, and joint mobilization exercises maintain functionality for years. Many patients never require surgical intervention.

Acupuncture in the foot: periarticular technique for osteoarthritis

Treatment protocol

Assessment and classification
1st visit

Examination of the metatarsophalangeal joint range of motion (active and passive dorsiflexion). Palpation of the dorsal osteophyte. Weight-bearing X-ray for classification (Coughlin grades I to IV). Exclusion of gout (if acute pain) and rheumatoid arthritis (if polyarticular). Assessment of habitual footwear.

Periarticular acupuncture
Sessions 1–4

Periarticular needles: 3–4 points around the metatarsophalangeal joint, avoiding insertion directly over the dorsal osteophyte. Acupuncture points: LR-3, SP-3, ST-44. Electroacupuncture 2–4 Hz between periarticular points. Goal: reduction of synovial inflammation and pain.

Biomechanical modification
Sessions 3–6

Prescription of footwear with rigid rocker-bottom sole to eliminate dorsiflexion during gait. Insole with Morton extension (support under the first metatarsal) when indicated. Joint mobilization exercises in dorsiflexion within the painless arc — maintain whatever motion remains.

Maintenance and monitoring
Sessions 7–10

Spacing of sessions according to response (weekly → biweekly). Reassessment of range of motion and functional pain. Annual radiographic monitoring of progression in grades II–III. Monthly maintenance sessions in cases with recurrent synovitis.

Clinical pearl: footwear is the forgotten treatment

Frequently asked questions

FREQUENTLY ASKED QUESTIONS · 04

Frequently Asked Questions

No. A bunion (hallux valgus) is the lateral deviation of the big toe with medial prominence — an alignment problem. Hallux rigidus is arthrosis of the joint with loss of motion and dorsal osteophytes — a problem of joint degeneration. The two can occur together in the same foot, but they are distinct conditions with different treatments. The physician easily differentiates them on physical examination.

Walking with appropriate footwear (rigid sole with rocker) is generally tolerated and even beneficial for maintaining mobility. Running depends on the degree of limitation: in grade I, many runners adapt with carbon-plate sneakers (high rigidity). In grades II and III, running can aggravate pain and alternatives such as cycling and swimming are more appropriate. Individual medical assessment determines the safe level of activity.

Established arthrosis (cartilage loss and osteophytes) is an irreversible structural change. What periarticular medical acupuncture can do is control synovial inflammation, reduce pain, and improve functionality — allowing the patient to walk with less discomfort. In combination with appropriate footwear, pain control can be significant and lasting, postponing or avoiding the need for surgery.

Surgery is considered when conservative treatment (acupuncture, appropriate footwear, anti-inflammatories) fails to control pain for at least 3 to 6 months. Cheilectomy (removal of the dorsal osteophyte) is indicated in grades II and III when the osteophyte is the main limiting factor. Arthrodesis (joint fusion) is reserved for grade IV with complete joint destruction. The surgical decision is individualized by the orthopedic physician.