Along with fasciocutaneous flaps and free flap techniques, skin grafts are a viable option in modern amputation surgeries and prosthetic fittings. It is possible for split-thickness skin grafts to hold under the forces applied by a prosthesis, but grafts will be most successful when not adherent to bone. Application of the graft over a cushioned, mobile muscle bed is ideal. However, without the fine layer of subcutaneous fat to absorb shear, grafts are not as durable as normal skin. Fortunately, liners made of elastomeric materials have improved prosthetic success for individuals with scar and skin graftings. This is of particular help for burn victims, as amputations in burned limbs often require skin grafts. The grafted skin and burn tissue will become more pressure tolerant over time if the shear and skin stretch are moderated by careful prosthetic fit and the introduction to the prosthesis is gradual. The amount of time wearing the prosthesis, the amount of force applied and activity levels must be carefully controlled and slowly calibrated forward. Over a period of many months the badly burned limb with amputation and free graft coverage may develop a tolerance that can provide optimum function. Such patients can often use prosthetic devices successfully and thereby avoid amputation at a higher level.

Skin problems remain a major concern for amputees throughout their lives. The amputation surgeon needs to be familiar with the many different types of short and long-term skin and wound healing problems. Post-operative infections, wound dehiscence and partial skin flap failure occur with unfortunate frequency in the short term healing process. Contact dermatitis, skin irritation, reactive hyperemia, callus formation, verrucuous hyperplasia, folliculitis, epidermoid cysts, hidradenitis, fungal infections and chronic breakdown are potential long-term skin ailments. Complicated skin problems often require multidisciplinary approaches requiring prosthetists, wound care specialists, dermatologists and the original surgical team.

The Muscle
Muscle makes up the bulk of the residual limb soft tissues. The amputee with a muscular, well-padded and balanced residual limb is less prone to chronic pain syndromes. Maximum retention of functioning muscles is essential to provide the residual limb with effective strength, size, shape, circulation, metabolic exchange and proprioception. Proper muscle function depends on the anatomic origin and insertion of the muscle. Without fixed resistance against which a muscle can forcefully contract, progressive weakness and atrophy develop. Distal muscle stabilization is a primary principle of amputation surgery. Whenever possible the sectioned muscle should be attached and stabilized in order to retain muscle function and to improve coverage and distal padding of the bone.

Historically, four types of muscle stabilization can be accomplished via surgical means. These include simple myofascial closure, myoplasty, myodesis and tenodesis. These closures have varying degrees of efficacy and efficiency in terms of muscle stabilization and in preserving function.

The first of these techniques, myofascial closure, encases the transected muscle by closing the outer fascial envelope over the top of the muscles. Myofascial closure in and of itself is not an effective means of muscle stabilization as it provides only minimal stabilization for the most superficial muscles, and provides inadequate distal attachment of the muscular tissue to the bone. It is primarily used when severe ischemia prevents more effective means of distal muscle fixation. However, even in the vast majority of today's dysvascular and diabetic amputations, more effective muscle stabilization is technically possible, and a wise endeavor.

In most diaphyseal amputations the muscle bellies themselves are transected, making it more difficult to attach the muscle to the bone than if their thicker distal fascia, aponeurosis or tendon were still present. This is the circumstance in the majority of transfemoral or transtibial amputations. Myoplasty, the second technique, is one by which the surgeon brings the muscles over the end of the bone and sews them to opposing muscle groups. Unfortunately, unless these muscles become firmly stabilized by scar tissue, the attachment can work antagonistically as a muscular sling, sliding back and forth over the distal end of the bone. This motion of muscle sliding over the bone is not good. It often creates bursal tissue and discomfort, both of which are easy to identify upon examination. Motion and an accompanying crepitance will be palpable over the end of the bone on physical examination. Because of the frequency of these complications, simple myoplasty is not recommended and the surgeon should instead attempt to secure the tissue directly to the distal end of the bone.

If the muscle groups themselves are attached directly and securely to the periosteum or the bone, it is called myodesis. In myodesis, the deepest layers of muscle are typically secured directly to the bone, while the more superficial layers of muscle are sewn to each other as a myoplasty. The myofascial envelope is then closed over the top of this muscular reconstruction.

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