Pain in the chest or side can be concerning, often leading individuals to worry about its origin. While many associate chest discomfort with the heart or breasts, muscles surrounding the rib cage are a common source. The serratus anterior muscle, in particular, can develop pain that mimics sensations in the breast. This discomfort is related to the muscle’s function and position, creating a confusing set of symptoms.
Anatomy of the Serratus Anterior
The serratus anterior is a broad, fan-shaped muscle located on the side of the chest. It originates on the surfaces of the upper eight or nine ribs and wraps around the rib cage like a sawtooth-edged sheet. The muscle fibers then travel backward to attach along the inner, medial border of the scapula, or shoulder blade.
Its primary function is to protract the scapula, which means pulling it forward and around the rib cage. This motion is fundamental to pushing movements and reaching forward, earning the serratus anterior the nickname “the boxer’s muscle” for its role in throwing a punch. It also works with other muscles to upwardly rotate the scapula, a movement necessary for lifting the arm overhead. By anchoring the scapula firmly against the thorax, it provides a stable base for arm movements.
Causes of Serratus Anterior Pain
Pain in this muscle arises from overuse, strain, or direct injury. Repetitive motions are a frequent culprit, common in activities like swimming, tennis, or weightlifting, where the arms are repeatedly moved overhead or forward with force. These actions can lead to microscopic tears and inflammation within the muscle fibers or at their attachment points on the ribs, resulting in localized pain.
Poor posture, particularly slouching or rounding the shoulders forward, places the serratus anterior in a constantly stretched and weakened state. This prolonged strain can make the muscle susceptible to injury and the development of tight, painful knots known as trigger points. These trigger points can refer pain to other areas, including the front of the chest and down the arm. Direct trauma, such as a blow to the side of the ribs or a fall, can bruise the muscle, while severe or persistent coughing can also cause strain.
Distinguishing Muscle Pain from Breast Tissue Pain
Differentiating between pain originating in the serratus anterior and pain from breast tissue involves paying close attention to the nature of the discomfort and its triggers. Muscular pain is described as a sharp, dull ache, or tenderness along the side of the chest wall. A key characteristic is its reproducibility; the pain worsens with specific movements like raising the arm, twisting the torso, or taking a deep breath. Palpating the area under the arm and along the ribs may reveal a specific point of tenderness that corresponds with the muscle’s location.
Certain symptoms are not characteristic of muscle strain and should prompt a medical evaluation. These include:
- A new lump or mass in the breast
- Changes in the skin such as dimpling or puckering
- Nipple retraction or discharge
- Unexplained redness or swelling of the breast
This type of pain is not related to movement or touch. Any chest pain accompanied by shortness of breath, dizziness, sweating, or pain that radiates to the jaw or left arm requires immediate emergency medical attention, as these can be signs of a cardiac event.
Relief and Treatment Options
For pain identified as muscular, initial management focuses on reducing inflammation and allowing the muscle to heal. Resting from the activities that aggravate the pain is a primary step. Applying ice packs to the tender area for 15-20 minutes several times a day can help decrease inflammation and numb the discomfort, especially within the first 48 hours of an acute injury.
Gentle stretching can help alleviate tension and restore flexibility to the strained muscle. A common exercise is the doorway stretch, where one stands in a doorway, places their forearms on the frame with elbows bent at 90 degrees, and then gently steps forward to feel a stretch across the chest and side. Wall angels, which involve standing with your back against a wall and sliding your arms up and down, can also help improve scapular mobility.
If the pain is severe, persists for more than a week with home care, or if any of the concerning symptoms previously mentioned appear, seek professional help. A physician or physical therapist can provide a definitive diagnosis and may recommend a tailored program of exercises and manual therapy to address underlying weakness or trigger points. In some cases, imaging tests like an MRI might be used to rule out other conditions.