Inferior malposition occurs when the implant descends below the IMF, extending beyond the intended breast footprint. It is the most common malposition type. ^, Presentations include bottoming out , where the IMF is stable, but the implant descends within the lower pole, increasing the IMF-to-nipple distance. ^, Another is the double-bubble deformity, characterized by 2 transverse folds across the lower breast. The upper fold represents the intended IMF, which remains visible postoperatively, while the lower fold indicates the level of the migrated implant. ^,

Although not a true implant malposition, waterfall deformity occurs when native breast tissue descends over an implant in its intended position, creating the illusion of inferior displacement. This is more common with high-riding, subpectoral implants. ^,

Lateral malposition describes implant displacement away from the sternum, resulting in a wider-than-desired separation between the breasts. A greater proportion of the implant may reside in the outer breast quadrants, which can create the appearance of medially rotated nipples. Lateral malposition can be more apparent in the supine position and during pectoralis muscle contraction.

Superior malposition involves upward displacement, resulting in a high-riding breast mound with insufficient lower pole volume and downward-gazing nipples. This is often seen in subpectoral implant placement via the axillary approach.

Medial malposition refers to the displacement toward the midline. Clinical findings range from mild medial drift to complete disruption of the intermammary sulcus. Symmastia is the extreme of medial malposition and occurs when the implants cross the midline and violate the midsternal fascia. This may result in lateral nipple displacement and distortion of breast contours.

Rotational malposition refers to implant displacement caused by rotation around 1 or more anatomic axes. This is most clinically apparent with anatomically shaped implants, where axial rotation can result in visible contour distortion due to the implant’s asymmetry. A subtype, anterior-posterior malposition, involves 180° rotation of round implants along a horizontal axis. This occurs most often with smooth, round, high-profile cohesive implants.

Intraoperative technique plays a central role in malposition risk. Key variables include pocket dissection, implant plane, and incision location.

Pocket dissection must be tailored to the implant and patient’s anatomy. Overdissection can result in an oversized pocket, allowing excessive implant mobility and increasing the risk of inferior, medial, or lateral displacement. Underdissection may lead to a tight pocket and superior malposition. If dissection extends too far inferiorly such that the native IMF remains superior to the new fold, a double-bubble deformity may result.

Implant plane also influences malposition. Subpectoral implants are more commonly associated with lateral displacement, likely due to repeated pectoralis muscle contraction. Superior malposition may occur if the inferior attachments of the pectoralis major are not adequately released. Subglandular implants are more susceptible to medial drift due to the lack of muscular support along the inner border. Adequate soft tissue coverage is essential in this plane, as poor coverage can increase the risk of visible malposition in all directions.

Incision type further impacts positioning. Compared to inframammary incisions, periareolar and transaxillary approaches have been associated with higher malposition rates. ^, Periareolar incisions may also increase the risk of capsular contracture, contributing to secondary malposition. Transaxillary incisions may increase superior malposition risk due to difficulty managing the IMF and releasing the inferior pectoralis attachments. ^, While IMF incisions offer more precise control of pocket dimensions, they may disrupt the native IMF if not properly reinforced. ^, Longer incisions may increase instability by allowing excessive manipulation and overdissection.

Implant characteristics, including dimensions, projection, fill type, gel cohesivity, surface texture, and shape, influence the likelihood of malposition.

Oversized implants relative to the patient’s tissue envelope can distort the breast footprint, overstretch supporting tissues and increase malposition risk. A tissue-based approach helps mitigate this by using objective anatomic measurements (eg, base width, skin stretch, and superior pole pinch thickness) to guide implant selection. ^,

Implant physical properties also matter. Highly cohesive, form-stable silicone implants retain their shape under pressure, minimizing strain on surrounding tissues. However highly cohesive and higher projecting implants may be more prone to rotational shifts. Saline implants are more susceptible to wrinkling, edge visibility, and shape distortion, particularly in patients with limited soft tissue coverage, which may explain their higher malposition rates in clinical studies.

Surface texture influences stability. Textured implants offer greater friction and tissue adherence, historically correlating with lower malposition rates. ^, However, concerns about breast implant-associated anaplastic large cell lymphoma (BIA-ALCL) have led many surgeons and patients to reconsider textured devices. ^,

Implant longevity is another consideration. Over time, devices become more prone to mechanical failure, with rupture rates of approximately 1% per year. Rupture can alter implant shape and volume, destabilizing the pocket, and leading to displacement. Similarly, capsular contracture risk increases over time and may result in firmness, deformation, and implant shift, typically in a superior or lateral direction.

Patient-specific risk for malposition arises from baseline anatomy and time-dependent changes in tissue support. Factors include chest wall configuration, breast footprint dimensions, and soft tissue integrity, which may differ between sides and should be evaluated individually during surgical planning.

Chest wall variations are not uncommon and can significantly influence implant positioning. Pectus excavatum and rectangular chest shapes have been associated with medial displacement, while pectus carinatum, rounded anterior chest walls, and thoracic prominence may increase lateral risk. ^, Chest wall asymmetry is also important, particularly in patients with scoliosis or other thoracic deformities, which often affect IMF position, breast volume, and projection due to rib cage rotation or uneven chest wall contours. ^, Though present preoperatively, these may become more apparent after augmentation and can both mimic and contribute to malposition ( Fig. 4 ). Documenting asymmetries preoperatively is essential for surgical planning.

Intraoperative visualization of chest wall asymmetry.

Any adjustment (planned or overdissection) of the breast footprint also increases malposition risk. A narrow breast base or significant asymmetry requires detailed planning and may warrant strategies such as IMF reinforcement. Patients with a short nipple-to-IMF distance (<4 cm), or a naturally high IMF may require IMF lowering, increasing the risk of inferior malposition. ^, This is especially relevant in tuberous or constricted breasts, where expansion is limited and IMF adherence resists repositioning. Adjustments to the IMF should be done with caution to reduce complication risk.

Soft tissue integrity is a critical determinant of implant stability. Mismatches between implant volume and tissue capacity increase malposition risk. Poor baseline tissue quality—including low thickness, high elasticity/stretch, or minimal fascial support—may predispose to early migration. These vulnerabilities may be exacerbated by aging, weight fluctuations, pregnancy, breastfeeding, hormonal changes, or inconsistent bra use, all of which can reduce tone and elasticity. ^,

Postoperative complications can alter implant position by distorting the pocket. Hematomas and seromas may expand the pocket, cause inflammation, reduce implant stability and lead to displacement. ^, Capsular contracture, though its etiology is multifactorial, is more common in patients with a history of hematoma, seroma, and contamination and can further contribute to malposition by contracting and displacing the implant, typically in a superior or lateral direction.

Implant rupture, while often implant age-related, may also result from surgical trauma or postoperative injury, leading to volume loss, asymmetry, destabilization of the implant pocket, inflammation, irritation, and capsular contracture. Timely follow-up is critical to detect and address these complications.

Even with optimal intraoperative results, trauma or inadequate postoperative care may affect implant position. Early vigorous activity, especially pectoral exercise in subpectoral implants, increases risk. Poorly fitted bras or stabilizers may also contribute. Clear patient instructions and close monitoring are essential for long-term stability.