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[Partial-shaft intracavernous prosthesis in treating erectile failure].

Many years' experience in the treatment of 140 patients by the authors' own method of pin intracavernous prosthetics with complete paired copulative success in 97% of them allows it to be considered the simplest, accessible, safest, and highly effective method. It is recommended as the method of choice in stable forms of erection disorders of various genesis in wide sexosurgical practice.

Chronic Disease↗

Stanmore custom-made extendible distal femoral replacements. Clinical experience in children with primary malignant bone tumours.

The use of extendible distal femoral replacements is a relatively new treatment alternative for malignant bone tumours in growing individuals. Although their appearance was widely appreciated, questions about functional practicality and longevity remain unclear. With longer follow-up, advantages of immediate functional restoration and beneficial psychological aspects seem to be overshadowed by an increase in complications such as aseptic loosening, infection or prosthetic failure. We have reviewed 18 children with such tumours who were treated between 1983 and 1990 by custom-made Stanmore extendible distal femoral replacements. Four died from metastatic disease within 2.5 years of operation and two required amputation for local recurrence or chronic infection. The remaining 12 patients were followed for a mean of 8.7 years (6 to 13.2). A mean total lengthening of 5.2 cm was achieved, requiring, on average, 4.3 operations. Using the Musculoskeletal Tumor Society rating score the functional result at review was, on average, 77% of the expected normal function, with seven patients achieving > or = 80%. Revision of the prosthesis was required in ten patients, in six for aseptic loosening, at a mean of 6.2 years after the initial procedure.

Adolescent↗

[Imaging mechanical complications of inferior vena cava filters].

Filter placement within the inferior vena cava is performed to prevent pulmonary embolism in patients with contraindications or failure of anticoagulant therapy. Several complications of vena cava filters have been described. However, mechanical complications related to IVC filters may not be of any clinical significance. The purpose of this pictorial essay is to present the imaging features of complications related to inferior vena cava filter placement.

Biomechanical Phenomena↗

Salvage of failed massive allograft reconstruction with endoprosthesis.

UNLABELLED: A subset of osteoarticular allograft reconstructions after tumor resection ultimately will fail in patients achieving long-term survival. There are several alternative surgical approaches to revising these reconstructions. We retrospectively evaluated the outcome of 20 patients who had allograft reconstruction with a modular endoprosthesis. All patients had a failed massive allograft (average length, 15.7 cm) after tumor resection about the shoulder and knee. The reasons for original allograft failure were fracture (14 patients), infection (five patients), and both (one patient). Followup of the patients averaged 159.7 months (range, 63-293 months) after allograft reconstruction and 77 months (range, 24-234 months) after endoprosthetic revision. The average number of operative procedures each patient had was 4.1 (range, 2-15 procedures). Two patients had amputations for resistant periprosthetic infections. A successful revision procedure was accomplished in 80% of the patients, and 90% of the patients retained functional limbs at recent followup. The predicted 5-, 10-, and 15-year survivals were 92%, 55% and 28% respectively. Musculoskeletal Tumor Society scores averaged 76% (range, 60-93.3%). When used to salvage massive allograft failure from infection and fractures, endoprosthetic revision preserves limb function with minimal complications. LEVEL OF EVIDENCE: Therapeutic study, Level IV (case series). See the Guidelines for Authors for a complete description of levels of evidence.

Adolescent↗

Peri-implant bone remodeling after total hip replacement combined with systemic alendronate treatment: a finite element analysis.

In order to decrease the peri-implant bone loss during the life-time of the implant, oral use of anti-osteoporosis drugs (like bisphosphonates) has been suggested. In this study, bone remodeling parameters identified from clinical trials of alendronate were used to simulate the effect of those drugs used after total hip arthroplasty on the peri-implant bone density. Results of the simulation show that the oral administrated drugs increase bone density around the implant and decreases, at the same time, the micromovements between the implant and the surrounding bone tissue. Incorporation of drug effect in numerical studies of bone remodeling is a promising tool especially to predetermine safe bisphosphonate doses that could be used with orthopedic implants.

Administration, Oral↗

Ahmed glaucoma valve implants in the pediatric population: the use of magnetic resonance imaging findings for surgical approach to reoperation.

PURPOSE: To describe and to evaluate a novel application of magnetic resonance imaging (MRI) in determining the Ahmed glaucoma valve (AGV) function after implantation. METHODS: Retrospective interventional case series of all surgical glaucoma patients in one practice were identified and orbital MRI series were performed. Orbital MRI findings were evaluated in all children who had undergone Ahmed glaucoma valve insertion. RESULTS: A total of six patients were identified, ranging in age from 1 to 14 years. Mean follow-up time ranged from 1 to 3 years from the time of first tube insertion. Gadolinium enhancement MRIs showed an enhanced large cystic cavity over the plate in five patients, indicating partial to complete patency of the outflow of the tube. One MRI failed to show an enlarged enhanced bleb over the plate region, indicating potential obstruction of outflow. Surgical irrigation of the tube displayed obstruction. Ahmed tube exchange was performed. Enhanced cystic bleb showed compression of the extraocular muscles in four patients. These patients exhibited mild to moderate restrictive strabismus. No lenticular opacification was noted in the four phakic patients. CONCLUSIONS: Early and late AGV failure and subsequent intraocular pressure rise are of great concern after pediatric glaucoma shunt surgery. Orbital MRI series should be considered in the cases of possible AGV drainage failure. In cases of reoperation, orbital MRI findings could be of great clinical value to evaluate for functional patency as well as for the EOM surgical intervention approach. To avoid unnecessary surgical exploration/explantation, orbital MRIs with gadolinium-dye enhancement should be considered in evaluating postshunt glaucoma surgical patients.

Adolescent↗

Ahmed valve implantation in glaucoma secondary to chronic uveitis.

PURPOSE: To evaluate the efficacy of Ahmed valve (AV) implantation in patients with uveitic glaucoma. METHODS: In total, 18 patients (19 eyes) with glaucoma secondary to chronic uveitis, who underwent AV implantation were retrospectively reviewed. Visual acuity, intraocular pressure (IOP), and glaucoma medications at the most recent examination prior to surgery, were compared with those of last postoperative examination. The surgical success was defined as IOP less than 21 mmHg and greater than 4 mmHg without loss of light perception and visually devastating complications at the last postoperative examination. Decrease in the number of glaucoma medications was also a criterion for surgical success. RESULTS: The mean follow-up period was 26+/-9.7 months. The mean preoperative and postoperative IOPs were 33.3+/-9.7 (range, 20-57) mmHg and 17.3+/-10.8 (range, 6-40) mmHg respectively (P<0.0001). The mean number of antiglaucoma medications was 3.5+/-0.8 (range, 2-5) preoperatively and 1.4+/-1.3 (range, 0-4) postoperatively (P<0.0001). Valve occlusion (five eyes, 26.3%) was the most commonly observed complication. Surgical success was achieved in 13 eyes (68.4%). The cumulative probability of success was 94.4% at 1 year and 60% at 2 years. Five eyes (26.3%) with IOP greater than 21 mmHg and one (5.3%) with corneal decompensation requiring penetrating keratoplasty were considered as failures. CONCLUSIONS: The implantation of AV is an effective surgical procedure for the management of uveitic glaucoma. The inflammatory background might contribute to the occurrence of valve occlusion, which is the most common complication. Prevention of this complication is an essential factor for improving the surgical outcome.

Adolescent↗

Clinical field testing of vulcanized rubber feet for trans-tibial amputees in tropical low-income countries.

In a prospective, controlled study, 186 prosthetic rubber feet of different designs were fitted to amputees with trans-tibial prostheses. There were 158 amputees available for follow-up. The amputee compliance was good and 89% were satisfied with their device. After 18 months of use one VI-Solid rubber foot from VVAF in Cambodia had failed, as compared to 11% failures with the same foot with a heel cavity, 3% with the EB-1 sandwich construction from POF in Vietnam, all performing significantly better than the 62% encountered with the vulcanized rubber foot from ICRC in Cambodia; the latter representing half of the feet failing in amputees walking bare-footed. Nearly all failures were located at the foot-sole or the keel. The failure rate was 20% for the HI-Cambodia foot after 12 months. After 24 months of use, still only one VI-Solid rubber foot had failed and this foot design was found superior to the others in regard of durability.

Adolescent↗

Risk of amputation following limb salvage surgery with endoprosthetic replacement, in a consecutive series of 1261 patients.

Endoprosthetic replacements are commonly used for limb salvage following surgical excision of bone tumours. Advantages include initial reliability, rapid restoration of function and their ready availability. Potential long-term problems include loosening, infection and mechanical failure. Increasing problems may lead to the necessity for amputation; this paper assesses that risk. A total of 1,261 patients have undergone endoprosthetic replacements in our centre in the past 34 years, with a total of 6,507 patient years of follow up. A total of 112 patients have had subsequent amputation. The reasons for amputation were local recurrence in 71, infection in 38, mechanical failure in two and chronic pain in one. The proximal tibia had the greatest risk of amputation (n=38/245). The time to amputation varied from 2 days to 16 years, with a mean of 31 months. The risk of amputation decreased with time, although 10% took place after more than 5 years.

Adult↗

[Prosthetic surgery for the rheumatoid hand].

In rheumatoid arthritis the complex biomechanics of the hand is impaired due to elongation of ligaments and displacement of tendons. This results in eccentric transfer of high loads to the arthritic joints. This pathological load transmission remains frequently after joint replacement. This is the main reason for the high failure rate after arthroplasty in the hand. Therefore, most of the endoprostheses are no longer in use. As long as techniques for reliable reconstruction of the periarticular structures have not been established, silicon arthroplasty will remain the golden standard. Arthroplasty of the wrist and the PIP joints is seldom performed. After arthrodesis of these joints, the function of the hand is sufficient and complications are seldom. Midterm results after resectional arthroplasty of the CMC-I joint show less complications and results comparable with silicon arthroplasty.

Arthritis, Rheumatoid↗

Redisplacement after ankle osteosynthesis with absorbable implants.

A total of 1202 fractures of the ankle were treated with absorbable implants made of polyglycolide/polylactide copolymer or self-reinforced polyglycolide and/or self-reinforced polylactide between November 5, 1984, and January 12, 1994. A redisplacement after fixation was diagnosed in 30 patients (2.5%). The redisplacement occurred in 8 of 934 (0.9%) simple ankle fractures and in 22 of 268 (8.2%) severer ankle fractures. A breakage or loosening of the absorbable implant was verified at reoperation in 8 cases and was suspected in another 9. A technical failure was the main reason in 13 cases. A reoperation was performed for 25 patients. The absorbable implants seem to provide a secure fixation in the majority of ankle fractures, but the use of these implants showed unsatisfactory results in unstable and comminuted fractures.

Absorption↗

Clinical field testing of polyurethane feet for trans-tibial amputees in tropical low-income countries.

In a prospective controlled study, 172 polyurethane feet of different designs were fitted to 155 amputees with trans-tibial prostheses. These were followed in respect of their durability. The amputee compliance was in general good, and 87% were satisfied with their device. After 18 months the failure rate of 20% with the CIREC spring-blade foot was significantly better than the others, but poorer craftsmanship, higher complaint rate and lower compliance rate cast some doubt on the results. The results with the conventional SACH foot constructions with polyurethane as filling and covering materials were so poor after 18 months that their use cannot be recommended in tropical areas of the developing world.

Adolescent↗

The current role of structural grafts and cages in revision arthroplasty of the hip.

Treating large segmental acetabular defects that comprise more than 50% of the acetabulum is one of the most difficult challenges in revision arthroplasty of the hip. One of the surgical options is a structural acetabular allograft. Unless these allografts are protected by a cage that extends from ilium to ischium, there is an unacceptable incidence of graft failure. The cage allows reconstruction at the correct anatomic level. It provides a scaffold for bone grafting (structural and morsellized). The use of cement to stabilize the cup allows the surgeon to adjust the cup position independent of the cage. The current generation of cages does not provide biologic fixation and with time may loosen or fracture. Recent experience with a combination of a trabecular metal shell protected by a cage may offer a more favorable environment for bone grafting with permanent biologic fixation of the cup cage construct.

Acetabulum↗

Segmental limb reconstruction after tumor resection.

Limb salvage of large segmental and osteoarticular defects after tumor resection has become the standard of care for most patients with musculoskeletal tumors because overall survival is the same when compared with that seen in amputation patients. This study examines limb salvage for the surgical management of large segmental defects in terms of local recurrence, complications, and functional outcome in both primary and metastatic lesions. We retrospectively identified 32 patients with benign or malignant tumors of bone who underwent resection and limb salvage reconstruction by means of a custom or modular metal implant between 1985 and 1995. The most common tumor sites were the proximal femur (41%), distal femur (37.5%), and proximal humerus (12.5%). Primary bone lesions accounted for 18 patients (56%); metastatic disease accounted for 14 patients (44%). Osteosarcoma (n = 11) and chondrosarcoma (n = 3) were the most frequent primary tumors. The overall limb salvage rate (91%) was high, yet complications (28%) were common. Except for 3 patients who underwent amputation after prosthetic failure, all surviving patients were independent with or without assistive devices at latest follow-up. In patients with advanced metastatic disease, average survival was 7.6 months. No cases of aseptic loosening or implant breakage were observed in patients followed up for 2 years or more. Treatment after tumor resection with a limb salvage prosthetic reconstruction has shown good functional outcomes with an acceptable complication rate. This modality, therefore, offers patients a more favorable functional outcome with a more energy-efficient gait when compared with limb amputation.

Adolescent↗

Treatment of an esophagorespiratory fistula by insertion of an esophageal Montgomery and tracheal dynamic stent after failure of conventional endoprosthesis.

Esophagorespiratory fistulae at the adult age can develop through malignant tumor growth, endoscopy, bougienage, laser therapy, or through a radiochemotherapy. We report a female patient with inoperable bronchial cancer, who developed a symptomatic esophagorespiratory fistula during radiochemotherapy with cisplatin. At first, conventional plastic tubes and then novel selfexpanding silicone-coated Gianturco-Song stents were used in an unsuccessful attempt to close the fistula. After the extraction of two Gianturco-Song stents, the insertion of a Montgomery-Salivary bypass stent in the esophagus and a dynamic stent in the trachea resulted in a permanent occlusion of the fistula. This case demonstrates that Montgomery-Salivary bypass stents do not tend to migrate due to their characteristic shape and self-fixation, and that the novel self-expanding, silicone coated Gianturco-Song stents can be extracted with rigid endoscopy if necessary.

Adult↗

A histomorphometric study of tissue interface by laminar implant test in rats.

Study of the implant-tissue interface is one of the fundamental issues in implantology, both odontologic and orthopedic. The characteristics of this interface will influence the success or failure of an implant. The aim of the present study was to evaluate histomorphometrically the capacity of different metals to osseointegrate employing laminar implants of zirconium, titanium, aluminum, and zirconium coated with diamond-like carbon. The experimental model herein allowed for the quantitative evaluation of the tissue-implant interface for different metals. The implants were placed in the tibiae of Wistar rats under anesthesia and allowed to remain in situ for a 30-day period. The interfaces of the zirconium and diamond-like coated zirconium implants exhibited better responses than the interface of titanium implants. Aluminum produced a local toxic effect, evidenced by osteoid formation.

Aluminum↗

Failure of a Björk-Shiley mitral valve prosthesis to open: clinical recognition.

Failure of a Björk-Shiley mitral valve prosthesis to open was recognized early in the postoperative period and required immediate replacement. The clinical finding was sudden, intermittent, severe hypotension associated with absent poppet sounds and simultaneous elevation in left atrial pressure. This unique and unusual hemodynamic picture was duplicated in four animal experiments. Routine monitoring of left atrial pressure is a useful postoperative adjunct that can provide early documentation of obstruction to left atrial outflow. Early recognition of the problem and immediate operative correction are mandatory.

Animals↗

Outcome of patients with nasolacrimal polyurethane stent implantation: do they keep tearing?

PURPOSE: To evaluate the results of nasolacrimal polyurethane stent implantation for the treatment of primary acquired nasolacrimal duct obstruction and the effects of obstructed nasolacrimal stent on subsequent dacryocystorhinostomy (DCR). METHODS: This study was designed as a nonrandomized, prospective clinical trial. Stent implantation was attempted in 53 obstructed lacrimal drainage systems of 47 patients. Stent placement was performed in a retrograde fashion through the external nare over a guide wire, which was introduced from the upper punctum. Occluded stents were removed either with nasal endoscopy or during DCR. External DCR surgery with silicone intubation was performed in cases with stent failure. RESULTS: The mean follow-up period was 23.4 months. The success rate of stent implantation was 60.4%, 37.5%, and 31.2% at 6-, 12-, and 18-month follow-up, respectively. Stent obstruction developed in 33 eyes. Twenty underwent external DCR with silicone intubation. During DCR surgery, varying degrees of chronic inflammatory reaction were detected in the lacrimal sac and nasolacrimal duct. The mean follow-up period after DCR was 10.3 months. Epiphora was relieved with DCR in all but one eye. CONCLUSIONS: The success rate of nasolacrimal polyurethane stent implantation for the treatment of primary acquired nasolacrimal duct obstruction is low and may induce inflammation and fibrous tissue formation. Although this may cause further difficulties in subsequent lacrimal surgery, epiphora could be relieved with meticulous technique.

Adult↗