Tendon Exposure Research Articles

Degloving Injuries of the Hand and Fingers

Wound coverage after a complete degloving injury of the hand and fingers is 1 of the most difficult problems in hand surgery. Important structures such as tendons, nerves, and bones are exposed and will necrose if not covered adequately. The goal of treatment should be coverage with a pliable, sensitive, and cosmetically similar tissue that will allow early mobilization. The authors' experience has led them to adopt the following general guidelines: replantation of the avulsed structures whenever possible; early transfer of a free composite flap from the foot for a complete and irreparable degloving injury of the thumb; and selection of the radial forearm flap for multiple finger lesions. Between 1981 and 1993, 13 patients were treated for degloving injuries of the hand and fingers. Revascularization of the avulsed structures was possible in only 4 patients. In 6 patients with degloving injuries of the thumb in whom replantation was not possible, the thumb was reconstructed using a free wraparound flap from the big toe. In 3 patients with degloving injuries of the fingers, coverage was obtained as an emergency measure using an island radial forearm flap. In conclusion, replantation should be attempted when the degloved skin is available and the vessels are not damaged; secondary reconstruction should be done as early as possible to limit the time of tendon, bone, and joint exposure.

Fascial flap coverage of Achilles tendon defects.

The exposed, often desiccated Achilles tendon presents a difficult wound that cannot always be solved with the use of regional tissue. A series of 15 consecutive patients with wounds associated with previous failed repairs (n = 5), radiation (n = 1), trauma (n = 4), pressure sores (n = 3), and burn contractures (n = 2) is presented. Patients with osteomyelitis of the calcaneus were not included. All were covered with free fascial flaps from parietotemporal or forearm donor sites and skin grafts. There were two partial flap losses. Complications were minimal, and all patients were mobilized and ambulating within 2 months. Average follow-up was 4 years. Those with peripheral vascular insufficiency were revascularized prior to free tissue transfer. Vascularized fascia covered with skin grafts provides the treatment of choice for the localized Achilles tendon exposure not exceeding 10.0 cm. Advantages include (1) provision of thin, pliable tissue that permits gliding, (2) minimal bulk, (3) simultaneous donor- and recipient-site dissections, (4) transfer of mobile tissue that can be wrapped around tendon, and (5) early wound coverage and mobilization.

Early Adipofascial Flap Coverage of Deep Electrical Burn Wounds of Upper Extremities

The adipofascial flap is a useful method for treating deep electrical burn wounds requiring early definitive wound closure to preserve vital structures and function. In the past 2 years, 14 deep electrical burns of the upper extremities involving exposure of tendon, nerve, bone, or blood vessels requiring immediate vessel reconstruction were covered with an adipofascial flap. The latter was a local random turnover flap of the fascia and its overlying subcutaneous fat. All flaps were successfully elevated and applied to severe wounds in order to preserve underlying structures. There were no serious complications. Tendon gliding under the flap was found to be excellent during second reconstructive surgical procedures. The reconstructed limbs had satisfactory preservation of function.

Use of the bilobed flap for coverage of exposed structures on the fingers

An original surgical procedure for the repair of soft tissue defects localized on the dorsal aspect of the proximal phalanx of the fingers is described. A patient was seen with a posttraumatic soft tissue loss corresponding to the dorsal aspect of the second metacarpophalangeal joint and the adjacent proximal half of the proximal phalanx of the index finger with extensor tendon exposure. The repair of the defect using a local flap taken from the second web space and the dorsum of the proximal phalanx of the long finger provided excellent coverage with early movement and a good functional result.

Limb Salvage of Infected Diabetic Foot Ulcers with Microsurgical Free-Muscle Transfer

This study was comprised of 9 diabetic patients with 10 infected foot ulcers, including osteomyelitis in 4 limbs and gangrene in 3 limbs. Adequate debridement of these complicated wounds inevitably resulted in exposure of bones or tendons. All defects were successfully reconstructed with free gracilis muscle flaps covered with split-thickness skin grafts. No recurrence of ulcer or infection was noted in the muscle-transplanted area during the follow-up period. Laser Doppler perfusion monitor measurement showed that the perfusion unit of the denervated free muscle flap increased to a peak at the second week after transplantation; the neovascularization of the grafted skin, the progressive decrease of the muscle swelling, and the decreased interstitial pressure may be the main contributing factors. The perfusion unit of the muscle flap reached equilibrium with the surrounding tissue at about 8 weeks after microsurgical transfer. Lower extremity amputation is a major health problem in the diabetic population. The microvascular free-muscle transfer was proved to play an effective and important role in limb salvage in diabetic patients with infected foot ulcers. The gracilis muscle flap was recommended due to its lack of bulkiness and minimal donor site deformity.

The Radial Forearm Flap

Thirty-five consecutive patients treated with the radial forearm flap were reviewed. This flap was used in head and neck reconstruction in 25 patients, soft-tissue cover of an extremity in 9 patients, and as a new technique for penile reconstruction in 1 patient. Osteocutaneous flaps were used for mandibular reconstruction in 13 patients. In 6 patients innervated flaps were used to provide sensation on the dorsum of the hand or on the weight-bearing surface of the foot. There was only one total flap failure and no partial failures. Recipient-site complications were few, with prompt healing and very acceptable appearance. Donor-site complications included partial loss of the skin graft with tendon exposure in 10 patients (33 percent), an unsatisfactory appearance in 5 patients (17 percent), and one case of radial fracture (8 percent). On functional testing, there was no significant loss of strength or joint mobility in the donor extremity in 19/20 patients. The authors recommend measures to reduce donor-site morbidity and conclude that, with an acceptable donor site, this flap is valuable in a variety of reconstructive applications.

Hoof Injuries

Major surgery for wounds of the foot, compared with other parts of the body, requires a more detailed preparation and a more persistent aftercare. To approach severe hoof wounds with a routine applicable to drainage of a subsolar abscess is doomed to failure! Yet, in dealing with referral cases of hoof wounds, particularly those that have become chronic, the author has observed that the principles have been ignored and/or the routines inadequate. The hoof has a suitable capacity to heal, with complete reformation of hoof structures, if a healing environment is maintained for a long enough period of time. For severe wounds, such time must be measured in months. A lack of attentiveness to the principles of hoof wound care and impatience during convalescence are the reasons for persistent lameness or for the formation of chronic hoof defects. The amount of hoof loss or the presence of distal phalangeal and/or deep digital flexor tendon exposure are not limiting factors to a successful outcome. Also, the initial assessment of the wound may not present an accurate picture of the eventual outcome. Both the veterinarian and the client may need to be committed to the horse's care for weeks or months before the final result is apparent; however, experience and faithful commitment help to avoid misjudgments in the selection of cases for follow-through. After healing, the resultant hoof frequently has far less functional or cosmetic impairment than might seem apparent at the outset. Most hoof wounds respond to proper therapy and recover without a hoof wall defect. The time lapse between injury and definitive care is critical. The amount of hoof loss and the exposure of deep foot structures are less critical. Such cases should be handled as a high priority, if not on an emergency basis. Prolonged delay is to be feared; contamination becomes infection, which extends, over time, to deeper, vital structures of the foot, with an unfavorable impact on the prognosis. Deep, penetrating wounds that invade the podotrochlea require early, even emergency, attention in order to avoid permanent debility, mortality, or euthanasia.

Glycation induces expansion of the molecular packing of collagen

Exposure of rat tail tendon to a reducing sugar results in covalent attachment of the sugar to collagen, a process termed glycation, and leads to the formation of stable intermolecular cross-links. We have used X-ray diffraction to study the changes in the crystalline unit cell of rat tail tendon collagen brought about by glycation. Ribose was selected as a model compound for most of the study because its reaction with proteins is faster than that of glucose, and therefore more convenient for laboratory studies, but glucose and glyceraldehyde were used as well. A kinetic model describing the process of glycation by ribose and subsequent cross-link formation has been developed. Glycation resulted in an expansion by more than 12% of the unit cell that describes the three-dimensional structure of rat tail tendon collagen. The expansion was in a direction perpendicular to the axes of the rod-shaped molecules, indicating that the intermolecular spacing of the collagen increased. Thus, the structure of collagen in rat tail tendon is significantly altered by glycation in vitro. The expansion was not isotropic, but was directed parallel to the (1 2 ̄ 0) planes, one of the three major planes of the quasi-hexagonal structure that is densely populated by collagen molecules. It is hypothesized that this expansion is brought about by the formation of one, or at most a few, specific intermolecular cross-links in the overlap zone that act to push the molecules apart. It is likely that similar structural changes in collagenous tissues are caused by glycation in vivo during the natural course of aging, and that these changes are accelerated in chronic hyperglycemia such as that associated with diabetes. Analysis of the structure of glycated rat tail tendon potentially can give us new insight into the detailed molecular structure of collagen.

Collagenous Materials Enhance Healing of Chronic Skin Ulcers

AbstractType I collagen in a porous sponge form attracts fibroblasts in culture and accelerates repair of animal wounds. This study examines the effect of type I collagen sponge and flakes on healing of chronic skin ulcers. Patients included in this study had skin ulcers.Patients included in this study had skin ulcers characterized by loss of dermis and epidermis without exposure of muscle, tendon or bone. Patients showing evidence of systemic infection or patients with ulcers that decreased in area during an initial three week observation period were excluded.Three out of seven patients treated with a collagen sponge and twelve out of fourteen patients treated with collagen flakes showed a 40% decrease in wound area after six weeks of treatment. In comparison, eighteen control patients showed no change in wound area over the same time interval. These results suggest that collagen flakes are effective in initiating healing of chronic skin ulcers.

The application of turn-over flaps to burn wounds

Satisfactory coverage of some deep burn wounds is very difficult. During the past year, 20 de-epithelialized turn-over flaps have been used to cover deep burn wounds in 17 patients. Most of the wounds resulted from electrical injuries which caused exposure of tendons, nerves, bone or joint space. A turn-over flap is a convenient local flap for covering deep burn wounds and reducing morbidity. They adhere well, cause less contracture, and make a good bed for the overlying graft. One disadvantage is that healthy tissue around the wound is not always available; another is questionable tendon gliding. Complications consisted of partial flap necrosis, osteomyelitis and an epithelial cyst. Over-all results for the reconstruction of difficult burn wounds were considered exceptionally good.

Ocular rotation as a tool for superior oblique tendon exposure.

In several clinical studies involving superior oblique surgery it was noticed that the posterior insertion of the superior oblique tendon can be moved outside from the undersurface of the superior rectus muscle. This was achieved by rotating the eye in a maximum nasal and downwards direction while avoiding intorsion or retraction of the globe. Traction was applied on the superior temporal quadrant of the globe.

The hazards of surgery in irradiated tissue.

Tissues subjected to irradiation undergo structural and physiologic changes often inexorably progressive. Surgical procedures may be performed in such tissues with good wound healing but also may be followed by serious complications which cause poor end-results, prolong hospitalization, and threaten life. Some of the complications that make surgery in irradiated tissue more difficult or hazardous are the following: (1) infection; (2) poor wound healing; (3) slough; (4) exposure of tendons, bone, or other important structures; (5) difficult hemostasis and or secondary hemorrhage; (6) difficult dissections; (7) rapid spread of carcinoma released from the incarceration of fibrosis; (8) radio-osteonecrosis; (9) induced tissue allergies; (10) narcotic addition from treatment for intolerable pain, and (11) general inanition. All these are fundamentally the result of diminished blood supply, lowered vitality of the irradiated tissue, and excessive fibrosis. Most all of these complications can and do follow surgery in normal tissues or in tissues damaged

Surgical exposure of the flexor pollicis longus tendon

Primary and secondary tendon repair in the metacarpal (thenar) zone of the thumb has been successfully performed. The zone can be explored by a proximal extension of the volar zig-zag incision used over the phalanges of the thumb. The surgical anatomy of this area is fully described and illustrated and the results of two successful cases given.

Reconstruction of Distal Phalangeal Injuries with Homodigital Island Flap: a Case Report

Background: Reconstruction of distal phalangeal defects with exposure of bone, tendon, or joint can be a difficult reconstructive problem, particularly since immediate coverage is of paramount importance for preserving function. The objectives of distal phalangeal defect or fingertip reconstruction included preservation of functional length and sensibility, prevention of symptomatic neuromas, acceptable donor site morbidity, the absence of cold intolerance, mineralization of aesthetic deformity, and quick return to occupational activities.Patients and Method: A review of one case, 26 years old male with phalangeal defect at tip to radial site of 3th finger of right hand, with tendon and bone exposed. After adequate debridement, shape and size of the defect are measured, the flap designed at the ulnar site of the same finger and the vascular of the flap is marked to palmar arch. Lazy “S” incision performed, donor flap is elevated with pedicle and transferred to the recipient site. Donor site was covered up with skin graft. Result: After follow up the homo digital island flap was healed nicely and the skin graft take was 100%, length is less diminish, sensibility conformed with two-point description, joint flexibility is good.Summary: Homodigital island flap is a useful safe option for fingertip or distal phalangeal reconstruction because it offers multiple advantages in comparison with advancement, regional, and free flaps, with an almost negligible donor site defect and can be done in a 1-stage procedure.

Position of the surgeon in stapes surgery.

Exposure of the posterior tympanic compartment via a posterior tympanotomy incision has become a standard practice in stapes surgery. (The incision and exposure were originally advocated by Lempert¹as an approach to tympanosympathectomy.) Experiences with the conventional arrangement in which the surgeon makes the incision standing or sitting posteriorly to the patient have revealed definite anatomical inadequacies, since the surgeon's vision naturally is directed to the anterior canal wall and the anterior tympanic compartment. Because of the angle of vision the surgeon must in effect look backward to visualize the posterior canal wall. If he uses straight oculars the effect is further increased (Fig. 1). Good exposure of the stapedial tendon, eminentia pyramidalis, posterior aspect of footplate, and posterior crus, is frequently difficult because of the degree of annular overhang. A good deal of blind curettage of annulus is necessary and frequently results in unnecessary trauma to chorda tympani.

Lower extremity skin coverage in children.

In the child with an extensive burn, a more complete coalescence of postage stamp grafts, with sturdier epithelium, takes place, and new superficial venous channels spring up in a relatively short time. When tendon exposure occurs there will often develop a granulation tissue covering from the surrounding areas within 10 to 14 days. This is less time than it would take to prepare an abdominal-pedicle or a cross-leg flap. Long-standing immobilization of a joint of a child or exposure of the joint of a child are not the major problems that they are in the adult. Comparison between the adult and the child, from the problem of the simple small superficial coverage to that of the larger deep areas, can be made in practically every circumstance.

The hazards of surgery in irradiated tissue.

Tissues subjected to irradiation undergo structural and physiologic changes often inexorably progressive. Surgical procedures may be performed in such tissues with good wound healing but also may be followed by serious complications which cause poor end-results, prolong hospitalization, and threaten life. Some of the complications that make surgery in irradiated tissue more difficult or hazardous are the following: (1) infection; (2) poor wound healing; (3) slough; (4) exposure of tendons, bone, or other important structures; (5) difficult hemostasis and or secondary hemorrhage; (6) difficult dissections; (7) rapid spread of carcinoma released from the incarceration of fibrosis; (8) radio-osteonecrosis; (9) induced tissue allergies; (10) narcotic addition from treatment for intolerable pain, and (11) general inanition. All these are fundamentally the result of diminished blood supply, lowered vitality of the irradiated tissue, and excessive fibrosis. Most all of these complications can and do follow surgery in normal tissues or in tissues damaged