Dorsal Interossei Muscles Trigger Points

Introduction

The dorsal interossei muscles are small but powerful muscles in the hand and foot, responsible for finger and toe abduction and fine motor control. When trigger points develop in these muscles, they can cause pain in the hands, fingers, feet, and toes, often mimicking carpal tunnel syndrome, arthritis, or metatarsalgia.

Name and Area

  • Name: Dorsal Interossei

  • Area:

    • Hand: Located between the metacarpal bones, spanning from the proximal phalanges to the metacarpals.

    • Foot: Located between the metatarsal bones, spanning from the proximal phalanges to the metatarsals.

Indications

Dorsal interossei trigger points may contribute to:

Hand:

  • Pain in the Back of the Hand and Between the Fingers

  • Weakness or Discomfort When Spreading the Fingers Apart

  • Pain That Radiates to the Wrist (Mimicking Carpal Tunnel Syndrome)

  • Difficulty With Precision Grip (E.g., Writing, Typing, or Playing an Instrument)

  • Finger Fatigue or Cramping During Repetitive Tasks

Foot:

  • Pain on the Top of the Foot and Between the Toes

  • Pain That Increases When Walking or Wearing Tight Shoes (Can Mimic Metatarsalgia or Morton’s Neuroma)

  • Difficulty Spreading the Toes Apart

  • Toes Feeling Stiff or Cramped (Especially in the Morning or After Activity)

Pain from these muscles is often mistaken for arthritis, nerve compression, or vascular issues.

Muscle Action

  • Hand:

    • Abducts the Fingers (Spreads Them Apart)

    • Assists in Finger Flexion at the MCP Joint and Extension at the PIP/DIP Joints

    • Supports Grip Strength and Dexterity

  • Foot:

    • Abducts the Toes (Spreads Them Apart)

    • Stabilizes the Foot During Walking and Running

    • Prevents Toes From Overlapping in Tight Shoes

The dorsal interossei muscles are crucial for fine motor control, balance, and coordination.

Signs and Symptoms

Individuals with dorsal interossei trigger points often report:

Hand:

  • Aching Pain Between the Metacarpal Bones

  • Difficulty Holding Small Objects (E.g., Pens, Keys, or Needles)

  • Tingling or Numbness in the Fingers (Can Be Mistaken for Carpal Tunnel Syndrome)

  • Weakness in Finger Dexterity (Difficulty Typing or Playing an Instrument)

  • Increased Hand Fatigue With Prolonged Use

Foot:

  • Pain in the Top of the Foot, Especially Near the Toes

  • Pain That Worsens With Walking, Running, or Wearing Tight Shoes

  • Toes Feeling Stiff or "Cramped" When Moving Them Apart

  • Pain Between the Metatarsal Bones, Mimicking Morton’s Neuroma or Metatarsalgia

  • Difficulty Maintaining Balance on Uneven Surfaces

Pain worsens with repetitive hand or foot movements, gripping, or prolonged walking.

Perpetuating Factors

Common causes of dorsal interossei trigger points include:

Hand:

  • Repetitive Fine Motor Movements (Typing, Playing Instruments, Sewing, Writing, Texting)

  • Forceful Finger Spreading or Squeezing (Rock Climbing, Gaming, Using Hand Tools)

  • Tight Grip on Objects for Long Periods (Holding a Steering Wheel, Holding a Phone, or Using a Mouse)

  • Wearing Gloves That Restrict Finger Movement

Foot:

  • Wearing Tight or Narrow Shoes (High Heels, Cleats, or Dress Shoes)

  • Excessive Walking or Running on Hard Surfaces

  • Toe-Curling Movements or Unstable Foot Positioning (Dancing, Ballet, or Sports That Require Quick Foot Movements)

  • Foot Deformities or Poor Arch Support (Flat Feet or High Arches)

Trigger Point Referral Pattern

Trigger points in the dorsal interossei refer pain to:

  • The back of the hand and between the fingers

  • The top of the foot and between the toes

  • The metacarpal and metatarsal bones (Mimicking Arthritis or Nerve Pain)

Pain from these muscles is often confused with nerve compression syndromes or joint inflammation.

Differential Diagnosis

Dorsal interossei trigger points may be mistaken for:

Hand:

  • Carpal Tunnel Syndrome (Pain, Tingling, and Numbness in the Fingers, Particularly at Night)

  • Arthritis (Joint Pain and Stiffness, Often Worse in the Morning)

  • Ulnar Nerve Compression (Weakness in Finger Abduction and Clawing of the Fingers)

  • De Quervain’s Tenosynovitis (Pain at the Base of the Thumb and Wrist, Rather Than Between the Fingers)

Foot:

  • Metatarsalgia (Pain in the Ball of the Foot, Often Worse With Walking)

  • Morton’s Neuroma (Pain Between the Toes With a "Pebble in the Shoe" Sensation)

  • Stress Fractures in the Metatarsals (Pain That Worsens With Impact Activities)

  • Peripheral Neuropathy (Tingling, Numbness, and Burning Pain in the Feet)

A thorough hand or foot examination is necessary to rule out these conditions.

Associated Trigger Points

Dorsal interossei trigger points often co-exist with:

Hand:

  • Flexor Digitorum Profundus (Finger Pain and Weak Grip Strength)

  • Extensor Digitorum (Wrist and Finger Pain During Typing or Gripping Movements)

  • Thenar and Hypothenar Muscles (Thumb and Pinky Finger Pain)

Foot:

  • Plantar Interossei (Pain in the Bottom of the Foot and Between the Toes)

  • Tibialis Posterior (Arch and Ankle Pain, Affecting Foot Stability)

  • Peroneus Longus/Brevis (Lateral Foot and Ankle Pain, Can Affect Balance and Gait)

Anatomy and Innervation

Muscle Origin Insertion Innervation
Dorsal Interossei (Hand) Metacarpal bones Proximal phalanges and extensor expansions Ulnar nerve (C8–T1)
Dorsal Interossei (Foot) Metatarsal bones Proximal phalanges of toes 2–4 Lateral plantar nerve (S2–S3)

The dorsal interossei muscles in the hand and foot are controlled by different nerves but perform similar functions.

Patient Examination

A comprehensive examination should include:

  • Palpation: Identify tender nodules along the metacarpals (hand) or metatarsals (foot).

  • Grip Strength Testing: Assess weakness in spreading or gripping movements (hand).

  • Toe Mobility Testing: Check for difficulty or pain when spreading the toes (foot).

  • Weight-Bearing and Gait Analysis: Look for balance issues or pain during walking (foot).

Corrective Actions

Manual Therapy

  • Trigger Point Release: Apply sustained pressure on the metacarpals and metatarsals.

  • Massage Therapy: Improves circulation and reduces tension in the hand or foot.

Stretching

  • Finger and Toe Spreading Exercises: Improves mobility and reduces stiffness.

  • Palm and Foot Stretching: Helps maintain flexibility in the intrinsic hand and foot muscles.

Strengthening Exercises

  • Rubber Band Finger and Toe Exercises: Strengthens the dorsal interossei for better dexterity and balance.

Postural and Ergonomic Adjustments

  • Wear Properly Fitted Shoes With Enough Toe Space

  • Use Ergonomic Keyboards and Mice for Hand Comfort

  • Take Breaks From Repetitive Hand or Foot Movements

➡️ Learn more about Trigger Points

Sources:

  • Travell, J. G., & Simons, D. G. (1983). Myofascial Pain and Dysfunction: The Trigger Point Manual (2nd ed.). Williams & Wilkins.

  • Simons, D., & Travell, J. (1999). The Trigger Point Manual, Volume 2: The Lower Extremities. Williams & Wilkins.