Clinics in podiatry最新文献

Injected fluid silicone serves as a soft prosthetic device and is an effective alternative to surgery in the management of corns and calluses. The material can relieve pain in weightbearing scars, reduce the incidence of recurring neuropathic ulcers, and protect skin at points of bony pressure. Augmenting subcutaneous tissue reduces both the vertical forces that cause direct pressure and the shear stresses imposed on plantar skin during horizontal acceleration or deceleration. The only significant side effect has been fluid migration, which is asymptomatic upon weightbearing and is seen only rarely when small amounts are implanted. Histologic examination of long-term biopsy and necropsy specimens has revealed no adverse tissue response. The safety and efficacy of injectable silicone as a soft-tissue implant in the foot have not been confirmed by the Food and Drug Administration, and pending completion of authorized investigation, the material is not available. Successfully completed studies, federal approval, and proper use could provide relief for millions of people who suffer from these common foot disorders.

Silicone rubber arthroplasty has been used in the foot with great success and with devastating failure. In an effort to understand why certain cases are successes and why certain cases are failures, a systematic investigation of several factors is necessary. A certain relationship exists among the material of which the implant is made, the design of the implant and the function it is asked to perform, and the host response to the material or implant. Simply because a material has been shown inert when placed in relatively large pieces in the body is not reason enough to support its use. The design of the implant must be such that it re-establishes function parallel to an anatomic manner. Host response to a prosthesis may be viewed in light of the tissue response to the foreign body and also with regard to its effect on bone, synovium, and articular cartilage as an organ. One must consider not only biologic compatibility but also compatibility of physical properties and physiologic function. This article has attempted to address and organize implant surgery in just this manner described. Silicone rubber arthroplasty has been a very satisfying procedure for both patient and surgeon. Complications do occur, and it is up to the surgeon to provide the analysis. The manufacturer may provide the prosthesis but the responsibility lies with the surgical community to use implantation in a proper and appropriate manner.

The topic of artificial tendons and ligaments for the foot and ankle has been investigated. Close attention has been given to three implants, the Silastic-rod implant, the carbon-fiber implant, and Marlex mesh. A brief historical background was given to the development of the lateral ankle reconstructive procedures and to the development of the individual artificial prostheses. The biologic reactions produced by the implants have been presented. Carbon-fiber implants and Marlex mesh induce a fibrous growth that produces a neotendon or neoligament, depending on their use. Silastic-rod implantation establishes a hollow tube with qualities very similar to the normal tendon sheath. Carbon fiber and Marlex mesh are directly implanted and used as a temporary tendon or ligament. During this time, they act as a scaffold on which the new tendon or ligament is formed. Silastic-rod implants are incorporated into a two-stage tendon-graft procedure. The Silastic rod is used during stage one to develop a new tendon sheath. Placement of an autologous tendon within the newly formed sheath occurs in stage two. Details of the actual procedure have been presented. Any tendon used in the transfer should be of similar strength with similar expansive qualities. These implants have many potential uses in podiatry. They are particularly useful in trauma cases and patients that present with ankle instability. Research pertaining to the development of an ideal suture and anastomosis technique is still needed.

The results of approximately 1000 digital implant arthroplasties performed since 1977 are reported. Only 10 have been removed, 8 from infection and 2 from trauma. The complication ratio is considered minimal, and the procedure is recommended in selected cases as an alternative to or in lieu of resection arthroplasty or digital arthrodesis.