Jodhpur Technique

Excerpt

The JODHPUR TECHNIQUE is a very simple, yet very effective and extremely low-cost innovative modification of the standard skin grafting technique. In simplified terms, it refers to an autologous non-cultured, non-trypsinized keratinocyte-melanocyte cellular graft technique developed and perfected by a working group of leading dermatology surgeons of Jodhpur (a heritage city in the state of Rajasthan, India). The long learning curve of mastering tissue grafting techniques, and the lack of expert set-up requiring special cellular culture media, trypsinization, etc. in a majority of public sector hospitals in developing countries were the two main contributing factors that propelled the innovative improvisation of the Jodhpur technique.

Background

Skin grafting is perhaps one of the oldest surgical techniques employed for the closure of a wound or coverage of desquamated/peeling skin resulting from burns, scalds, trauma, chronic non-healing wounds, and surgical removal of large skin growths. The second major application of skin grafting is in replacing a specific cell-deficient skin such as melanocyte-depleted depigmented skin or post-burn leucodermic scar with a normal donor skin with the intent of replenishing the cellular pool of the recipient area, thereby re-pigmenting it.

It is essential to know the essential difference between a skin graft and a flap repair. In contrast to flaps that remain attached to a source of blood supply through a pedicle, skin grafts are completely avascular and replacement is necessary over a prepared recipient bed to restore the nourishment of the donor skin.

In Dermatosurgery, skin grafting is most commonly used in vitiligo surgery and for the induction of healing of chronic non-healing ulcers (CNHL). It may also be needed during scar revisions and in post-burn leucodermic scars.

Different types of skin grafts:

Broadly speaking, skin grafts can fall into three classifications:

(1) Based on the cellular/tissue composition of the graft :

1. Split-thickness skin grafts (STSG) - full epidermis and a superficial part of the dermis.

2. Full-thickness skin grafts (FTSG) - full epidermis and full dermis, and a small part of the subcutaneous fat

3. Composite grafts - these are composed of skin and another type of tissue, usually cartilage.

Split-thickness skin grafts further subclassify into ultra-thin STSG, thin or Thiersch–Ollier (0.125 to 0.275 mm) STSG, intermediate, or Blair–Brown (0.275 to 0.4 mm), and thick or Padgett (0.4 to 0.75 mm) split-thickness grafts.

(2) Based on the technique of harvesting the graft

(2.1) Tissue grafts - These techniques refer to the direct harvesting of sheets of cells from the donor area. They may be procured by:

1. Mini/Micro Punch grafts (MPG) - miniature or micro-sized punches of skin are harvested from the donor site and placed in punched out holes in the recipient skin

2. STSG - Skin of the desired thickness gets harvested using a dermatome, and it comes out as a thin sheet

3. Suction blister Grafts - Ultra-thin skin grafts get harvested by a special protocol of applying suction at the donor site

Although the process of harvesting tissue grafts involves minimal surgical equipment and cost, tissue grafts can be useful for only a limited surface area per treatment session.

(2.2) Cellular grafts -

Cellular grafts include cellular suspensions of pure melanocytes, or keratinocytes, or their admixture, with latest inclusions being that of dermal cells and/or follicular cells. Cellular grafts are prepared from a smaller surgically harvested skin sample, by either culturing it or using it as a non-cultured suspension. The major advantage of these suspension and culturing techniques is that they permit treatment of affected skin manifold larger than the donor area.

1. Cultured cell suspension techniques - Although these provide treatment of a much larger surface area of the affected skin, the cultured techniques suffer from the limitations of being time-consuming, expense owing to the need for special culture media and specific laboratory conditions maintained over several weeks and need of highly trained personnel.

2. Non-cultured cellular grafting techniques - To obviate the logistic and cost issues of cultured techniques, the harvested skin gets subjected to cell separation by incubating it with trypsin/trypsin-EDTA at 37 degrees C for 20 to 30 minutes. The resultant suspension is thoroughly rinsed with lactated Ringer's solution, followed by complete manual separation of any dermal tissue. The epidermal fragments are centrifuged for a few minutes to create a homogenous cell pellet, which then gets resuspended in lactated Ringer’s solution. Thus, despite being technically and logistically less demanding than the cultured techniques, the non-cultured techniques, most common being the melanocyte-keratinocyte transplant procedure (MKTP), also involve special chemicals such as trypsin for cell separation and need for a decent laboratory back-up with at least an incubator and centrifuge.

As we learn the intricacies of the Jodhpur technique in subsequent sections, one would realize that it is, in fact, a marriage of the cellular and tissue skin grafting techniques. It provides the advantage of large recipient area coverage with a small donor skin area (typical of cellular techniques), albeit without the need of an expensive infrastructure, chemicals, devices or culture media.