How do hair transplants work?

Although hair loss and volume thinning is a variant of aging, it may occur prematurely in many individuals due to underlying pathologies and trauma to the scalp. It is estimated that around 60% of the population worldwide suffer from some form of hair loss. To address this complaint a wide variety of over-the-counter medications, serums, tonics, and medical appliances are commercially marketed every year, however, the success rates of these non-surgical modalities are usually highly variable and unpredictable. Hair transplants were first introduced in the mid-twentieth century and are currently the most rapidly evolving surgical procedures that aim to restore hair growth in individuals suffering from partial or complete baldness. Unlike medications, transplants offer rapid, natural-looking results and are highly effective for many types of hair loss, although they have limited potential to preventing further hair thinning.

What types of Hair Transplants exist?

This surgical technique involves the removal of hair follicles from one part of the body in order for them to be transplanted to the desired site. The treatment was primarily offered to manage male pattern baldness but is now also employed to restore eyelashes, eyebrows, beard hair, and to fill in scars caused by trauma or surgery, such as face-lifts and previous hair transplants. 

There are two main types of procedures:

Follicular Unit Transplantation (FUT)

This procedure, also known as the Follicular Unit Strip Surgery (FUSS), involves the removal of a strip of skin from the donor area from which tiny follicular units are extracted with the help of a microscope. The strip size is typically around 6 to 10 inches in length and harvested from the back of the scalp. The extracted units contain one or several hair follicles that have the potential to form new hair strands. These units are then transplanted to the desired site through multiple small incisions or punctures holes. The number of grafts depends upon factors such as quality of hair, size of the donor strip, and type of hair. The donor site is closed with sutures for approximation.

Follicular Unit Extraction (FUE)

Similar to FUSS, this surgical technique is also based upon the harvesting of follicular units, however, rather than removing a whole skin strip, a small punch tool is employed to directly extract follicular units from the intact scalp skin. This procedure therefore does not require any sutures and is less noticeable than FUSS.

Both surgical procedures are associated with a high success rate and satisfactory outcomes, although some literature suggests that FUE requires more skill and duration of surgery in comparison to FUSS.

Recovery after hair transplant?

Hair transplant can be carried out in daycare units under local anesthesia. Overnight hospital admission is generally not needed, and patients are usually sent home the same day. Patients may be prescribed antibiotics prophylactically, along with some pain medications. Some centers also recommend the use of hair growth stimulants, such as finasteride (Propecia) or minoxidil (Rogaine), to maximize the results of the procedure.

Patients are mostly advised to avoid combing or brushing the grafted scalp for at least three weeks.

Typically, around 10-80% of the transplanted hair is documented to grow back within 3-4 months after the procedure. 

Do hair transplants last?

With every transplant there is always a risk of graft rejection. Fortunately, most surgeries have high success rates, and rejection occurs in only a minority of cases. Although the majority of patients end up with thicker-looking hair, the main post-op concern is how long the effects of the transplant lasts. Many individuals in fact continue to experience hair thinning and loss after the procedure, leaving them with an unnatural or patchy appearance. Consequently, for longer-lasting results, many patients opt for different touch-up procedures and subsequent transplants. This may involve filling in any areas that are not hairy enough, or blending the follicles to achieve a more natural look. Multiple pieces of research show adjunct plasma therapy to improve outcomes in 75% of transplanted cases.

A study published in 2016, followed 122 patients who underwent FUE using body hair after a mean interval of 3 years post-op. The patients were asked about their healing status, hair growth in transplanted areas, and overall satisfaction with their surgeries. It was found that patients were generally satisfied with the results of their procedure, giving average scores of at least 7.8 out of 10 on a Likert-like scale.

Some individuals also prefer skin flap surgery, tissue expansion, or scalp reduction techniques over hair transplant to acquire a more dramatic change.

Side effects and complications associated with hair transplants

Similar to any invasive procedure, hair transplants are also associated with a few surgical complications. However, with the advancement of plastic surgery, these complications have been reduced to a low frequency. These may include:

  • Pain, redness, bleeding, and itching are few common complaints observed immediately after the procedure. These usually tend to resolve within a week or two.
  • A phenomenon known as shock loss is a relatively common side effect observed after hair transplant. It is the benign temporary thinning of the original hair post-procedure, and simple reassurance is known to be effective.
  • True infections of the recipient side are uncommon, however, local infection around the surgical sutures may occur if improper hygiene care is carried out postoperatively. These infections are self-limited and usually resolve after suture removal. In some individuals, inflammation of hair follicles (known as folliculitis) may also occur, which can be treated with topical antibiotics and compression.
  • An epidermal cyst may occasionally form on the recipient site requiring drainage.
  • In cases where a large donor flap is harvested, the affected site may have tension on the suture line leading to dehiscence and scarring.
  • The most common side effect noted in the majority of cases is scarring and unnatural-looking new hair. The FUSS method in particular is usually associated with a long, linear scar that may become camouflaged as the new hair grows around it. In some instances, it may, however, remain visible if the surrounding hair is thin.




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Saxena K, Savant SS. Body to scalp: Evolving trends in body hair transplantation. Indian dermatology online journal. 2017 May;8(3):167.

Sharma R, Ranjan A. Follicular Unit Extraction (FUE) Hair Transplant: Curves Ahead. Journal of Maxillofacial and Oral Surgery. 2019 Dec:1-9.

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