Uneven Shoulders: Why One Shoulder Is Higher

Common causes

Posture and muscle imbalance

The most common reason is everyday habit:

• carrying a bag, backpack or child on the same side
• dominant-arm use; right-handed people often have a slightly lower right shoulder
• one-sided sports such as tennis, baseball, golf or swimming with uneven technique
• leaning on one elbow at a desk or working with a screen to one side
• tight muscles on one side of the neck and upper back

This functional asymmetry looks better when you deliberately stand straight and often improves with exercises.

Scoliosis

Scoliosis is a sideways curve of the spine with rotation of the vertebrae. Adolescent idiopathic scoliosis is the most common type, starting between 10 and 18, and is more likely to progress in girls. Signs:

• one shoulder or shoulder blade higher or more prominent
• an uneven waist, with more of a gap between arm and body on one side
• one hip higher
• a rib hump on one side when bending forward
• the head not centered over the pelvis

Mild curves usually cause no pain.

Leg length difference

A leg length discrepancy tilts the pelvis, and the spine compensates, which can make the shoulders uneven. It may be structural (one leg bone truly shorter) or functional (from foot or hip problems).

Kyphosis and other spine conditions

Kyphosis, an exaggerated forward rounding of the upper back, often occurs with some sideways asymmetry. Spinal fractures, arthritis and degenerative scoliosis in older adults can also tilt the shoulders.

Shoulder and collarbone problems

• Old collarbone fracture that healed shortened or angled
• AC joint separation: a bump at the top of the shoulder
• Muscle wasting after a rotator cuff tear or nerve injury

Nerve problems and a winged shoulder blade

Injury to the long thoracic nerve or spinal accessory nerve weakens the muscles that hold the shoulder blade, causing it to wing out and the shoulder to droop. It may follow heavy lifting, a sports injury, neck surgery or a viral illness.

Neck problems

Torticollis, a tight neck muscle that tilts the head, can raise one shoulder. In babies it is usually congenital; in adults it may come from muscle spasm or cervical dystonia.

Congenital differences

Sprengel deformity, an undescended, high shoulder blade, is a rare congenital cause noticeable in early childhood.

How to check for scoliosis at home

1. Stand behind the person, who stands straight with feet together and arms relaxed.
2. Look at shoulder height, shoulder blades, the waist creases and hip height.
3. Ask them to bend forward with arms hanging and knees straight (Adams forward-bend test).
4. Look along the back. A hump on one side of the ribs or lower back suggests scoliosis.

A rib hump or clear asymmetry warrants a doctor's visit.

How doctors assess uneven shoulders

A doctor examines posture, spine and shoulder movement, muscle strength, reflexes and leg lengths, and performs the forward-bend test, sometimes with a scoliometer to measure rotation. Tests may include:

• standing spine X-rays to measure the curve (Cobb angle)
• leg length measurements or X-rays
• shoulder X-rays or ultrasound
• nerve conduction studies if nerve injury is suspected
• MRI if there are neurological signs, pain or an unusual curve pattern

A curve of 10 degrees or more on X-ray is defined as scoliosis.

Treatment

• Postural asymmetry: switch sides when carrying bags, use both straps, adjust workstation setup, and do exercises to stretch tight muscles (upper trapezius, chest) and strengthen weak ones (lower trapezius, rhomboids, serratus anterior). A physical therapist can tailor a program.
• Scoliosis: small curves are monitored with X-rays during growth. Curves of about 25 to 40 degrees in growing children are often treated with a brace worn many hours a day. Curves over about 45 to 50 degrees may need spinal fusion surgery. Scoliosis-specific physical therapy may help some patients.
• Leg length difference: a shoe lift or insole for differences over about 1 cm.
• Nerve injuries: physical therapy; most recover over months, with surgery for those that do not.
• Fractures and joint injuries: treatment of the underlying problem.

Frequently asked questions

Why is one of my shoulders higher than the other?

The most common causes are posture habits, handedness, carrying bags on one side and muscle imbalance. Structural causes include scoliosis, a leg length difference, an old collarbone fracture and nerve injury. If the difference is noticeable or worsening, especially in a teenager, get it checked.

Are uneven shoulders a sign of scoliosis?

They can be. Uneven shoulders are one of the earliest visible signs of scoliosis, particularly with an uneven waist, one hip higher, or a rib hump when bending forward. Many people with uneven shoulders do not have scoliosis, so an exam and sometimes an X-ray are needed.

Can uneven shoulders be fixed?

Uneven shoulders caused by posture or muscle imbalance often improve with stretching, strengthening exercises and changing habits over several weeks to months. Structural causes such as scoliosis or bone differences may not fully correct with exercise but can be managed with bracing, shoe lifts or surgery when needed.

What exercises help uneven shoulders?

Useful exercises include stretches for the upper trapezius and chest, and strengthening for the lower trapezius, rhomboids and serratus anterior, such as rows, wall slides and scapular squeezes. A physical therapist can identify which side is tight or weak and set a tailored program.

Should I worry about uneven shoulders in my child?

Uneven shoulders in a child or teen are worth checking with a pediatrician, especially during growth spurts. Early detection of scoliosis allows monitoring and bracing if needed, which can stop a curve from worsening. Most mild asymmetry turns out to be postural.