Metatarsalgia
Synonyms and keywords: Metatarsophalangeal joint capsulitis, Stone bruise, Ball-of-foot-pain

# Overview
Metatarsalgia (literally metatarsal pain, colloquially known as stone bruise) is a general term used to refer to any painful foot condition affecting the metatarsal region of the foot (area just before the toes, commonly referred to as ball-of-the-foot). It is actually a common overuse injury that can affect the joints and bones of the metatarsals. Metatarsalgia is most often localized to the  the first metatarsal head (the ball of the foot just behind the big toe).  There are two small sesamoid bones under the first metatarsal head.  The next most frequent site of metatarsal head pain is under the second metatarsal.  This can be due to either too short a first metatarsal bone or to "hypermobility of the first ray" (metatarsal bone + medial cuneiform bone behind it), both of which result in excessive pressure being transmitted into the second metatarsal head. Metatarsalgia is the irritation and inflammation of joint capsule surrounding these metatarsal heads due to excessive pressure over prolonged periods of time. Patient complaints of pain in the joint itself with the feeling of a marble in the shoe or a bunched up sock.

# Pathophysiology
- Metatarsalgia usually occurs due to excessive pressure at the metatarsal heads over prolonged periods of time
- This results in the irritation and inflammation of joints, capsule or ligaments at metatarsal heads (ball of the foot), leading to metatarsophalangeal joint capsulitis aka metatarsalgia
- Common sites of involvement include:
First metatarsal head (most common)
Second metatarsal head
Third metatarsal head
Fourth metatarsal head
- First metatarsal head (most common)
- Second metatarsal head
- Third metatarsal head
- Fourth metatarsal head

# Causes
Metatarsalgia can be caused by any of the following:
- Abnormal foot mechanics (putting excessive amount of weight bearing pressure on the ball of the foot beneath the toe joint)
- Repetitive foot motion exerting pressure on the ball of foot resulting in connective tissue degeneration
- High level of activity
- Tight Achilles tendon
- Severe foot deformities such as:
Bunion
Hammer toe
- Bunion
- Hammer toe
- Second toe longer than the big toe (or short first metatarsal bone), disturbs the normal forefoot balance which leads to the shift of an increased amount of weight to the second metatarsal bone
- Structurally unstable arch of the foot i.e. high arch
- Prominent metatarsal heads
- Excessive pronation
- Tight toe extensor muscles
- Weak toe flexor muscles
- Hypermobile first foot bone
- Improper fitting footwear (womens dress shoes, other restrictive footwear with narrow toe box)
- High heels
- High impact activities/sports (involving running or jumping) without proper footwear/orthotics such as:
Track and field running
Tennis
Football
Baseball
Soccer
- Track and field running
- Tennis
- Football
- Baseball
- Soccer
- Older age (thinning of foot fat pad leads to more susceptibility to pain in the ball of the foot)

# History and symptoms
- The primary symptom of metatarsalgia is the pain at the end of one or more of the metatarsal bones (ball of the foot) with the following characteristics:
Pain is either sharp or dull
It worsens on weight bearing such as walking (barefoot) or running
It comes on gradually over a period of several months, not suddenly
- Pain is either sharp or dull
- It worsens on weight bearing such as walking (barefoot) or running
- It comes on gradually over a period of several months, not suddenly
- Patient has a feeling of:
A ''marble'' in the shoe
Walking on ''pebbles''
A bunched up sock
Standing on a ''pea''
- A ''marble'' in the shoe
- Walking on ''pebbles''
- A bunched up sock
- Standing on a ''pea''
- Patient often perceives it as a feeling of lump inside or underneath the foot
- Swelling at the base of toe
- Difficulty wearing shoes
- Crossover toe (end-stage of capsulitis)

# Imaging Fingings
Following imaging tests may prove to be helpful in diagnosing and differentiating metatarsalgia from other causes of forefoot pain:

## X-ray
X-ray helps to exclude other causes of forefoot pain

## MRI
MRI helps to diagnose & differentiate other causes of pain in mid-foot and metatarsal regions such as:
- Traumatic disorders
- Circulatory conditions
- Arthritis
- Neuroarthropathies
- Other conditions leading to biomechanical imbalance

## Bone Scan
A bone scan pinpoints to the places of inflammation

## Ultrasound
- Ultrasound imaging of foot gives valuable information regarding the alterations responsible for causing metatarsalgia
- It also helps to detect & exclude other causes of pain in the metatarsal foot region. These conditions include:
Morton's neuroma
Bursitis
- Morton's neuroma
- Bursitis

# Treatment
- First step in the treatment of metatarsalgia is determining the cause of the pain and then carrying out the measures to eliminate that cause

## Conservative medical therapy
- Following are the conservative measures for the treatment of metatarsalgia:
Changing the improper fitting footwear with shoes having:
High and wide toe box (allowing the foot to spread out)
Rocker sole (decreases the stress on the ball-of-the-foot)
Unloading the pressure to the ball-of-the-foot by following foot-care products:
Orthotics with metatarsal pad which is placed behind the ball-of-the-foot (relieves the pressure, and redistributes the weight from painful area to the more tolerant areas)
Gel metatarsal cushions
Metatarsal bandages
- Changing the improper fitting footwear with shoes having:
High and wide toe box (allowing the foot to spread out)
Rocker sole (decreases the stress on the ball-of-the-foot)
- High and wide toe box (allowing the foot to spread out)
- Rocker sole (decreases the stress on the ball-of-the-foot)
- Unloading the pressure to the ball-of-the-foot by following foot-care products:
Orthotics with metatarsal pad which is placed behind the ball-of-the-foot (relieves the pressure, and redistributes the weight from painful area to the more tolerant areas)
Gel metatarsal cushions
Metatarsal bandages
- Orthotics with metatarsal pad which is placed behind the ball-of-the-foot (relieves the pressure, and redistributes the weight from painful area to the more tolerant areas)
- Gel metatarsal cushions
- Metatarsal bandages

## Surgery
- In some cases, off-loading of the joints doesn't eliminate the pain
- In such cases, patient should be referred to foot and ankle surgeon for the surgery for pain relief

# Prevention
Primary preventive measures for metatarsalgia include the following:
- Avoid high level of activity putting excessive pressure on the ball of the foot
- Avoid excessive pronation
- Avoid high heels
- Avoid improper fitting footwear such as womens dress shoes or other restrictive footwear with narrow toe box
- Avoid high impact activities or sports (involving running or jumping) without proper footwear/orthotics such as:
Track and field running
Tennis
Football
Baseball
Soccer
- Track and field running
- Tennis
- Football
- Baseball
- Soccer