Understanding Over-the-Muscle Tissue Expanders for Breast Reconstruction

One of the early conversations to have with your reconstructive surgeon when considering implant based breast reconstruction is whether the tissue expanders will sit under (subpectoral/subglandular) or over the muscle (prepectoral). 

While both offer pros and cons, the use of over-the-muscle (prepectoral) tissue expanders has been gaining attention and utilization. 

Over-the-muscle tissue expanders are flexible temporary implants (think deflated balloons) that are placed under the skin but above the pectoral muscles. This method contrasts with the traditional submuscular placement, where a portion of the expanders are positioned beneath the pectoral muscles.

Over weeks or months, saline or air is periodically injected into the expander through a small valve on the surface of the expander, slowly stretching the overlying skin and creating a pocket for a future permanent implant.

Advantages of Over-the-Muscle Placement

  1. Reduced Pain and Discomfort: Avoiding muscle disruption leads to less postoperative pain and a quicker recovery.
  2. Improved Aesthetic Outcomes: Positioned above the muscle, these expanders can provide a more natural appearance and avoid issues like animation deformity, where the implant moves unnaturally with muscle contraction.
  3. Shorter Surgery Times: The procedure is generally quicker and less invasive, as it avoids cutting or manipulating the chest muscles.

Considerations and Challenges

  • Skin Quality: Requires sufficient healthy skin post-mastectomy to cover the expander, which might not be available in all patients, especially those who have undergone radiation therapy.
  • Risk of Rippling: There might be a higher visibility or palpability of the expander, especially in patients with thin skin.
  • Capsular Contracture: As with all implants, there is a risk of capsular contracture, where hard scar tissue forms around the implant creating discomfort and implant distortion.

While this decision should be made in conjunction with your reconstructive surgeon's input, many patients who opt for over-the-muscle expanders report a positive experience due to the less invasive nature of the procedure and its shorter recovery periods. 

Choosing the right type of breast reconstruction is a deeply personal decision that should be made with comprehensive information and support. Over-the-muscle tissue expanders represent a promising option for many, offering advantages in comfort and aesthetic outcomes.


Back to blog