[Reconstruction of the orbits with polylactate implants: animal experimental results after 12 months and clinical prospects]. / Rekonstruktion der Orbita mit Polylaktat-Implantaten: tierexperimentelle Ergebnisse nach 12 Monaten und klinischer Ausblick.

In earlier experiments healing of large orbital wall defects in sheep occurred undisturbed by osteoconductive bone growth along biodegradable membranes when there was no interference with additional bone grafts or titanium miniplate osteosynthesis. In this experiment similar bilateral defects were reconstructed with poly(L/DL 80/20) lactide implants using a microporous membrane 0.5 mm thick without further support on one side, an 0.25 mm microporous membrane supported by solid polylactide buttresses and stabilized by polylactide dowels on the opposite side. After 12 months we found a symmetrical reconstruction of the normal anatomy of the orbits in CT and X-ray examinations. In contrast, histologic investigations revealed massive foreign-body reactions around degrading buttress implants and dowels especially. Milder reactions occurred in some orbits along the membranes as well, in contrast to our earlier experiments with 4-month follow-up. None of the implants had degraded completely 12 months after surgery. In our 12-month long-term survey, polylactide microporous membranes confirmed their osteoconductive potential in orbital wall reconstruction. Nevertheless, massive polylactic implants should not be considered for clinical application in the orbit because of significant late foreign-body reactions.

[Experimental reconstruction of the sheep orbit with biodegradable implants]. / Experimentelle Rekonstruktion der Orbita beim Schaf mit biodegradablen Implantaten.

In a complex animal model in sheep, polydioxanone (PDS) and polylactic membranes were used for the reconstruction of large orbital-wall defects. In a long-term experiment over 1 year, polylactic implants alone showed the best performance as compared with combinations involving autogenous bone grafts and titanium miniplate fixation. As soon as these polylactic implants are approved for human surgery, they will be used to solve the still challenging problem of anatomical reconstruction of large comminuted fractures of more than one orbital wall.

[Experimental reconstruction of sheep orbits using biodegradable implants]. / Experimentelle Rekonstruktion der Orbita beim Schaf mit biodegradablen Implantaten.

In a complex animal model in sheep, polydioxanone (PDS(®)) and polylactic membranes were used for the reconstruction of large orbital-wall defects. In a long-term experiment over 1 year, polylactic implants alone showed the best performance as compared with combinations involving autogenous bone grafts and titanium miniplate fixation. As soon as these polylactic implants are approved for human surgery, they will be used to solve the still challenging problem of anatomical reconstruction of large comminuted fractures of more than one orbital wall.

[Results of microsurgical reconstruction after vasectomy]. / Resultate der mikrochirurgischen Rekonstruktion nach Vasektomie.

Because of the increasing number of divorces surgical refertilisation by vasovasostomy has become increasingly important. Of 33 patients operated in the last decade, 32 could be reached for follow-up. The patency-rate was 86% and the pregnancy-rate 28%. Possible explanations for this discrepancy are discussed. The time lag between vasectomy and vasovasostomy was the most important prognostic factor. There was no difference in the results between one-layer and two-layer anastomosis. With an interdisciplinary approach the same patency rate as described in the literature was achieved.

Is soft tissue expansion in lower limb reconstruction a legitimate option?

From 1986 to 1994, a consecutive series of 34 patients had 37 expanders placed in their legs. Indications for expansion included removal of painful ro unstable scars, chronic post-traumatic ulcers and one benign skin lesion. In 13 patients the lesion or scar was greater than 5 cm in diameter. The area of expansion was mainly in the proximal and distal thirds of the lower limb. On three occasions two expanders were simultaneously used in the same patient. The treatment with this technique was ultimately successful in 23 patients (67.6%) but 15 of the 23 patients (44% of the 34 patients) had minor wound healing problems. Before 1990, technical complications such as leaking injection ports caused further small interventions in 6 patients without compromising the ultimate outcome. The goal was not achieved with the expansion technique in 11 patients (32%). 5 of these 11 patients could be treated successfully with another surgical modality. All 34 patients were re-evaluated with an average follow-up of 4.5 years. We conclude that tissue expansion is ideal for removal of localised areas of scar, repair of contour defects and excision of benign tumours. Contraindications of soft tissue expansion are, in general, extensive scarred areas with compromised blood supply after trauma, vascular disease and osteomyelitis. These conditions require reconstruction with well vascularised tissue such as muscle flaps. A compliant patient is essential for lower limb reconstruction with tissue expansion. In spite of the tempting simple method of tissue expansion, success in the lower limb depends not only on the indication but also on the operating technique of the plastic surgeon.

Low-dose UVB radiation perturbs the functional expression of B7.1 and B7.2 co-stimulatory molecules on human Langerhans cells.

In previous studies, we have shown that ultraviolet (UV) B radiation perturbs the APC function of Langerhans cells (LC) by interfering with as-yet unidentified co-stimulatory signals. Recently, B7.1 and B7.2 on APC were shown to deliver important co-stimulatory signals through interaction with their counter receptors CD28 and CTLA-4 on T cells. To determine whether UVB affects the functional expression of B7.1 or B7.2 on LC, B7.1 and B7.2 expression was studied on human LC by multiparameter flow cytometry. Little, if any, B7.1 or B7.2 was detected on LC freshly isolated from skin. However, following 48 h of tissue culture, expression of both B7.1 and B7.2 were markedly up-regulated. To test whether these molecules were functional, primary mixed epidermal cell leukocyte reactions (MECLR) were performed. Blocking monoclonal antibody (mAb) to B7.1 or B7.2 both inhibited the MECLR, with anti-B7.2 being much more effective than anti-B7.1. UVB radiation dose-dependently (100-200 J/m2) suppressed the culture-induced up-regulation of B7.1 and B7.2 on LC. Since LC exposed to the same UVB flux (UVB-LC) failed to stimulate alloreactive T cells in a MECLR, we questioned whether this was related to their inability to provide B7 co-stimulation. Indeed, when effective B7-CD28 signaling was ascertained by adding submitogenic doses of exogenous anti-CD28 mAb to UVB-LC, the proliferative response of alloreactive T cells was restored. We conclude that the suppressive effects of low-dose UVB radiation on the APC function of LC are, at least in part, due to an inhibition of functional B7.1 and B7.2 expression.

Rapid purification of human Langerhans cells using paramagnetic microbeads.

Detailed studies on the biology of Langerhans cells (LC), which account for only 1-3% of all epidermal cells, require isolation from their cutaneous symbionts. Several techniques of LC isolation have been reported, including positive enrichment with mAb coupled to immunomagnetic beads. The disadvantage of this technique is the size of the beads (approximately 2-5 microns), which can interfere with subsequent phenotypic and functional analyses. This limitation prompted us to test whether paramagnetic microbeads (15 nm) employed by the MACS system could be used to purify LC from human skin. To isolate fresh LC (fLC), epidermal cell suspensions (EC) were stained with anti-CD1a mAb and with appropriate secondary reagents conjugated to microbeads and to FITC. They were then passed over a separation column and exposed to a strong magnetic field. Thereafter both CD1a-depleted and CD1a-enriched cells were collected. Cultured LC (cLC) were isolated by staining 72-h cultured EC with anti-HLA-DR mAb followed by the same isolation procedure. Using this technique, we could routinely isolate viable EC that were 45-88% CD1a+ or HLA-DR+ as determined by FACS. Two-color FACS analysis demonstrated the majority of MACS-purified cells to be CD1a+/HLA-DR+, indicating that they were indeed LC. By transmission electron microscopy (TEM), the MACS-purified CD1a+/HLA-DR+ cells showed typical ultrastructural characteristics of LC. Furthermore, MACS-purified fLC or cLC were functionally intact, because they stimulated the proliferation of alloreactive T cells in a primary, one-way, mixed epidermal cell leukocyte reaction (MECLR). We conclude that MACS-separation is an efficient and rapid method to isolate human fLC and cLC of high purity and unimpaired function.

Clinical results of tension band fixation of avulsion fractures of the hand.

We report 100 cases in which a tension-band technique was used to secure fixation of avulsion fractures within the digits. Included are 51 bony mallet fractures that were subluxed or irreducible, 38 displaced bony gamekeeper's fractures of the thumb, 8 fractures of the lateral phalangeal base, and 3 avulsion fractures that involved the base of the dorsal aspect of the middle phalanx. We evaluated results on the basis of clinical and x-ray film criteria. Excellent or satisfactory results were found in all 38 bony gamekeeper's injuries. All but one gamekeeper's fracture healed; the one nonunion was asymptomatic. All eight patients with lateral avulsion fractures had an excellent or satisfactory result on clinical examination. Seven of the eight had an excellent result on x-ray film evaluation; the one malnuion was asymptomatic. Two of the three fractures with dorsal avulsions of the base of the middle phalanx had a satisfactory result on clinical and x-ray film examination; the one poor result was due to the severity of the comminution of the fracture. However, 21 of the 51 bony mallet injuries had a poor result both clinically and radiographically. We noted numerous postoperative complications including dorsal skin breakdown, superficial and deep infection, and secondary displacement of the fragment. Tension-band fixation is an excellent method for treating various avulsion fractures of the hand such as bony gamekeeper's thumb, lateral avlusion injuries, and dorsal avulsions of the middle phalanx. However, the treatment of bony mallet fingers with tension band fixation is less predictable and should be used with caution.

How does a pure muscle cross-leg flap survive? An unusual salvage procedure reviewed.

An exceptional indication for a cross-leg gastrocnemius flap used as a pure muscle flap in the distal third of the lower leg is presented. The vascular status of the patient after the accident and extensive colonized wounds in the injured lower leg did not favor any microvascular reconstruction. Because no cross-leg muscle flap has been mentioned in the literature so far, technical details of the procedure are explained. This case report leads to a discussion of the principles of wound healing in cross-leg muscle flaps as an example for early loss of axial blood supply. Furthermore, it adds new variety to the numerous procedures that use the gastrocnemius flap.

Epidemiological data and costs of burn injuries in workers in Switzerland: an argument for immediate treatment in burn centres.

A complete statistical evaluation of epidemiological data and costs of burn injuries in 1984 with a follow-up for 5 years is presented, considering a collective of 1.77 million workers in Switzerland. The majority of burns are minor injuries; only about 5 per cent of the burn victims are admitted to a hospital, 0.2 per cent died. Burn injuries at work are rare, mainly owing to strict safety measures. Only one-fifth of the costs caused by burns are due to medical treatment. All other expenses result from continuation of payments of salaries and annuities. The treatment of the few severely burned patients in burn units produces effective costs which are higher than the tariff paid by the insurance. Even so, the predominant portion of the enormous costs is taken up by wages while off work and annuities. As our conclusion we stress the importance of primary care for all severe burns including all burns of the hands in a specialized centre. Any economic effort for primary burn treatment, however high it may be, is justified if the duration of rehabilitation and invalidity can be reduced.

Perianal extramammary Paget's disease. Report of two cases.

Perianal (extramammary) Paget's disease is rare and corresponds to an intraepithelial adenocarcinoma arising from dermal apocrine sweat glands. Biopsy reveals the diagnosis. The condition is often associated with an underlying malignancy (carcinoma of the apocrine or eccrine glands, rectal carcinoma, anal carcinoma). Wide local excision is recommended when invasive growth is absent. For invasive cancer or when associated with a synchronous malignancy abdomino-perineal resection is the treatment of choice. Two cases of perianal Paget's disease are presented.

[Burns in workers in Switzerland: epidemiology and financial sequelae]. / Brandverletzungen bei Werktätigen in der Schwiez: Epidemiologie und Kostenfolgen.

A complete statistical evaluation of epidemiologic data and costs of burn injuries in 1984 with a follow-up for 5 years is presented, considering a collective of 1.77 million workers in Switzerland. The majority of burns are minor injuries; only about 5% of the burn victimes are admitted to a hospital, 0.2% die. Only one fifth of the costs caused by burns are due to medical treatment and rehabilitation. All other expenses result from continuation of payments of salaries and annuities. The few treatments of severely burnt patients in the burn units cause effective costs higher than the tariff paid by the insurance. Even so, the predominant portion of the enormous costs is taken up by wages while off work and annuities. As our conclusion we stress the importance of primary care for all severe burns including all burns of the hands in a specialized centre. Any economic effort for primary burn treatment, however high it may be, is justified if the duration of rehabilitation and invalidity can thus be reduced.

The neurosensory musculocutaneous tensor fasciae latae flap: long term results.

In 1971 we started covering pressure sores and unstable scars with transposition-rotation-muscle and musculocutaneous flaps. In 1980 we published the first results with 6 neurosensory musculocutaneous tensor fasciae latae flaps. Until April 1989, 31 tensor fasciae latae flaps (TFL) were used, and we review a consecutive series of 19 neurosensory TFL-flaps. Questions such as whether to delay the procedure; early and late complications; evolution of the sensation; and indications are outlined under the aspects of long term follow up studies. The conclusion is that if the neurological pattern permits a neurosensory flap, such flaps should be done because no local recurrence occurred. In extended neurosensory TFL-flaps sensation of the filling status of the rectum is improved, and sitting control and perception of the 'body scheme' are also improved.

The sensory tensor fasciae latae flap: a 9-year follow-up.

From January 1979 to April 1989, 19 neurosensory tensor fasciae latae flaps were used to cover ischial pressure sores in paraplegic patients. This flap provides protective sensation and improves the sensory control of the filling status of the rectum and the sitting control in a wheelchair. Patients were reexamined between 12 and 110 months; no recurrence or new pressure sores were seen. Indications, early and late complications, and evolution of the sensation are discussed.

Why the denervated gastrocnemius muscle flap should be encouraged.

The superiorly based, denervated gastrocnemius muscle flap is able to perform an aesthetically excellent and functionally good cover for defects of the upper one-third of the calf, including the knee, and the lower one-third of the thigh. A consecutive series of 41 muscle and musculocutaneous gastrocnemius flaps was analyzed. Thirty-six patients (88% of the patients who underwent surgery) could be reexamined. The mean follow-up time was 36 months, with a minimum time of 12 months. At the time of examination, all skin defects as well as the incidental concomitant osteomyelitis had completely healed; however, 40% of the patients have required secondary operations. One-half of the patients have a functional deficiency, and 20% showed areas with loss of sensation. After surgery with musculocutaneous flaps, all patients complained about the sensory loss of the saphenous nerve, and peripheral edema was seen more often than after surgery with a simple muscle flap. Muscle flaps with residual innervation showed more secondary wound breakdown and more contraction pain, due to spasms. The best results concerning function and aesthetics are achieved with denervated muscle flaps covered by a split-thickness skin graft. In this variation, the flap showed good and stable coverage without bulk, as well as minimal donor-site deformity; therefore, primary denervation must be considered. The anatomy of the motor nerves to the gastrocnemius muscle is shown.

[Facial injuries in bicyclists: epidemiological analysis and prophylactic consequences]. / Gesichtsverletzungen des Radfahrers: Epidemiologische Analyse und prophylaktische Konsequenzen.

Bicycle accidents in adults are common and concern frequently injuries to head and face. 150 of totally 216 patients with cycle accidents in a six month' prospective study at the Basel University Hospital showed face and head trauma. 85 severe facial injuries treated operatively by the Clinic for Reconstructive Surgery between 1985 and 1989 are analysed in detail. These facial injuries are rarely life threatening and normally the postoperative outcome is good. Nevertheless, usual bicycle helmets cannot avoid facial trauma. Therefore traffic educational programs are the most important prophylactic efforts. Technical progress and improvement of the bicycles ask for better trained cyclists. Further more, the importance of really respecting the traffic rules as well as the construction of separate cycle routes is stressed.

[Follow-up of extensive burns in an HIV positive patient. Case report]. / Verlauf einer ausgedehnten Verbrennung beim HIV-positiven Patienten. Fallbericht.

The case of a 33-year-old HIV-positive patient who suffered from second- and third-degree burn injuries involving 30% of the body surface is reported. She was treated by early tangential excision of the burnt skin and split-thickness mesh grafting. The burn wounds healed without complications within the usual time, with excellent cosmetic and functional results. In spite of the successful treatment, she suffered from fever and various infections for several months. With the appearance of these constitutional symptoms, we recognized the AIDS-related complex. Her general condition deteriorated continuously and 10 months after the accident she had to be admitted to a hospital again. The skin had nevertheless healed perfectly and in spite of not having compression treatment for the grafts or physiotherapy, she did not show any signs of hypertrophic scars. Some important conclusions drawn from this case are discussed. The fact that healing occurred without complications is in contrast to the results reported in the literature concerning impaired wound healing in AIDS patients with anorectal surgery. We therefore believe that the reluctant and perhaps even anxious attitude of the medical and nursing staff towards performing technical and expensive procedures in HIV-positive burn patients is not justified.