Ingrown toenails occur when the edge of the nail plate grows into the surrounding skin fold, leading to pain, swelling, and often infection. This condition is a common and frustrating problem, especially when it resolves only to return again and again. To break this loop of discomfort, it is necessary to identify why the ingrown toenail—most often affecting the big toe—keeps reappearing. Lasting relief requires addressing the structural, behavioral, or treatment-related factors that allow the nail to grow back improperly.
Anatomical and Inherited Factors
The physical structure of the foot and the shape of the nail itself are often reasons for chronic recurrence. Some individuals inherit toenails that are naturally more curved or convex, a condition sometimes referred to as pincer nails. This increased curvature naturally directs the sides of the nail plate downward, making it prone to piercing the surrounding skin fold.
The underlying bone structure of the toe, the distal phalanx, can also play a role in recurrence. If the bone is wider or the nail bed is larger than average, it can create constant pressure against the lateral nail folds. This congenital predisposition means that the structural conflict between the nail plate and the soft tissue makes repeated incidents highly probable. For these individuals, surgical alteration is the most reliable path to permanent relief.
Everyday Habits That Cause Relapse
Daily habits often act as the trigger that causes the nail to become ingrown. The most frequent behavioral cause is improper nail trimming, which involves cutting the toenail too short or rounding the corners. This technique encourages the nail to grow into the skin and can leave behind microscopic nail fragments, known as spicules, that continue to grow inward like a splinter.
Footwear is another major environmental factor. Shoes that are too tight, too narrow, or have a shallow toe box squeeze the toes together, forcing the nail edge into the surrounding skin. High-heeled shoes can exacerbate this issue by pushing the foot forward, concentrating pressure onto the big toe. Repeated microtrauma, such as that experienced during running or high-impact sports, also contributes by causing the toes to repeatedly impact the inside of the shoe, which can alter the nail’s growth pattern.
When Treatment Fails to Stop Recurrence
Ingrown toenail recurrence is often traced back to incomplete medical intervention, which addresses the symptom but not the source. Many temporary treatments involve only a simple nail avulsion, which is the removal of the offending nail edge without treating the nail root. While this procedure provides immediate relief, the nail matrix remains intact and simply regenerates the problematic section of the nail, often causing the ingrown condition to return within three to six months.
To achieve a permanent result, a procedure called a matrixectomy is necessary. This involves destroying the portion of the nail matrix responsible for growing the painful edge, usually through a chemical agent like phenol or via surgical excision. Procedures that do not include matrix destruction, such as simple nail avulsion, have recurrence rates as high as 73% to 83%. Combining partial nail avulsion with a chemical matrixectomy offers a much higher success rate, with recurrence rates dropping to less than 5%.
Strategies for Permanent Prevention
Preventing chronic ingrown toenails requires a combination of structural awareness and consistent behavioral changes. The most effective preventative step is to adopt the correct trimming technique: cutting the nail straight across, ensuring the edges remain visible. The nail should be long enough so that the corner sits comfortably above the skin fold.
Selecting appropriate footwear with a wide toe box allows the toes to spread naturally and reduces external pressure on the nail plate. For individuals with naturally curved nails, these preventative measures should be coupled with a low threshold for seeking professional care. If conservative measures fail after multiple attempts, consulting a podiatrist for a permanent procedure like a chemical matrixectomy is the most definitive way to stop the frustrating cycle of recurrence.