1/29. Polyester fibre prosthetic anterior cruciate ligament implant rupture: necrosis of ingrown connective tissue.AIMS: To describe the histopathological and microanalytical features in seven cases of ruptured Apex(R) polyester (Terylene(R)) fibre anterior cruciate ligament prosthesis. methods AND RESULTS: Transmitted and polarized light microscopy was performed in all cases; one case was investigated by immunohistochemistry, transmission electron microscopy and scanning electron microscopy, with backscatter and X-ray detectors for elemental microanalysis. For comparison we also studied synovial biopsy material and unused polyester fibres. In the excised ligaments there was much ingrowth of fibrous tissue accompanying a florid giant cell reaction to the individual intact polyester fibres throughout the ligaments. phagocytosis of particles of prosthesis-derived material was demonstrated and a striking finding was of necrosis of the ingrown connective tissue in the central portions of the ligaments. Hyalinized areas and 'neoligament growth' were less striking. A consistent finding in the polyester fibres was of small particles containing antimony, used as a catalyst in the manufacturing process. CONCLUSIONS: The pattern of reaction to the prosthetic material and the presence of necrosis differ from previous descriptions in animal and human explants of this and other prosthesis types. The mechanical effect of the necrosis is unlikely to be of significance with this ligament, which is load-bearing ab initio.- - - - - - - - - - ranking = 1keywords = ligament (Clic here for more details about this article) |
2/29. Spontaneous luxation of encapsulated intraocular lens onto the retina after a triple procedure of vitrectomy, phacoemulsification, and intraocular lens implantation.PURPOSE: To report the clinical and histological findings of a luxated intraocular lens (IOL) in the capsular bag. methods: review of a case. RESULTS: Twenty-three months after a triple procedure of vitrectomy, phacoemulsification, and IOL implantation for diabetic vitreous hemorrhage and cataract, the encapsulated IOL spontaneously luxated. Scanning electron microscopy showed sparsely distributed anterior and equatorial zonules, with only a few posterior zonules on the surface of the removed capusular bag. CONCLUSION: The absence of the anterior hyaloid membrane and posterior zonules and contraction of the lens capsule may cause dialysis of the zonules. Therefore, the anterior hyaloid membrane should be left in place in patients at low risk for the development of postoperative proliferation to maintain the long-term stability of the IOL.- - - - - - - - - - ranking = 0.0016364370325732keywords = membrane (Clic here for more details about this article) |
3/29. Late operative site pain with isola posterior instrumentation requiring implant removal: infection or metal reaction?OBJECTIVES: To elucidate the cause of late operative site pain in six cases of scoliosis managed with Isola posterior instrumentation that required removal of the implants. METHOD: Microbiologic examination of wound swabs and enriched culture of operative tissue specimens was undertaken in all cases. Histologic study of the peri-implant membranes also was conducted. RESULTS: The presentation in all cases was similar: back pain appearing between 12-20 months after surgery, followed by a local wound swelling leading to a wound sinus. In only one of these cases was the discharge positive for bacterial growth. Implant removal was curative. Histologic examination of tissue specimens revealed a neutrophil-rich granulation tissue reaction suggestive of an infective etiology despite the failure to isolate organisms. Within the granulation tissue was metallic debris that varied from very sparse to abundant from fretting at the distal cross-connector junctions. A review of recent literature describing similar problems suggests that late onset spinal pain is a real entity and a major cause of implant removal. CONCLUSIONS: On reviewing the evidence for an infective etiology versus a metallurgic reaction etiology for these cases of late onset spinal pain, it was concluded that a subacute low-grade implant infection was the main cause. Histologic findings would seem to confirm low-grade infection. There may be more than one causative factor for late operative site pain, as it is possible that fretting at cross connection junctions may provide the environment for the incubation of dormant or inactive microbes.- - - - - - - - - - ranking = 0.00081821851628658keywords = membrane (Clic here for more details about this article) |
4/29. Microscopic metallic wear and tissue response in failed titanium hallux metatarsophalangeal implants: two cases.The membranes present at the implant-bone interface were retrieved from two patients with titanium single stem hallux implants that had failed. Both patients had pain and valgus deformity of the hallux, and radiographs showed a radiolucent shadow around the implant stem, with thinning of the dorsal cortex of the proximal phalanx in one patient. After removal of the implants, arthrodesis of the first metatarsophalangeal (MP) joint was performed. Histologic analysis of the membrane tissue at the implant-bone interface showed a synovial-like appearance. There was a fibrous tissue stroma adjacent to the bone surface, with multiple regions of scalloping covered by mononuclear cells. Fine metallic debris was seen throughout the fibrous tissue. Multinucleated foreign body giant cells were sparsely observed associated with fine particulate metallic wear debris similar to observations from failed total hip arthroplasties. The histologic appearance is evidence that foreign-body granulomatous infiltration associated with metallic wear debris may be a causative factor of peri-implant osteolysis leading to aseptic loosening and failure of titanium single stem hallux implants.- - - - - - - - - - ranking = 0.0016364370325732keywords = membrane (Clic here for more details about this article) |
5/29. Case challenges in knee surgery: what would you do?In an interactive case presentation session, the faculty discussed management of complex primary and revision knee arthroplasty issues. Principles discussed included: preoperative evaluation of the failed knee arthroplasty, intra-articular versus extra-articular deformity correction, ligamentous balancing, managing the unstable total knee arthroplasty, bone deficiency management, rotational positioning of prosthetic components, selection of articular constraint in the revision knee, and extensor mechanism balancing.- - - - - - - - - - ranking = 0.1keywords = ligament (Clic here for more details about this article) |
6/29. Partial malposition of PFO closure device: indication for elective surgical removal? Discussion of indications, procedural and anatomical aspects.Partial malposition of a PFO closure device occurred, probably due to a right atrial ligamentous structure. Despite absence of residual shunt and uneventful postprocedural course, elective surgical removal was performed. Indications, procedural and anatomical aspects are discussed.- - - - - - - - - - ranking = 0.1keywords = ligament (Clic here for more details about this article) |
7/29. Posterior dislocation of a cruciate-retaining total knee arthroplasty following an acute bacterial infection.BACKGROUND: We report a rare complication of posterior dislocation of a cruciate-retaining total knee arthroplasty following an acute bacterial infection. The mechanism of dislocation proved to be septic loosening of the femoral component and a tear of the posterior cruciate ligament near to the femoral insertion site. The tear arose during the treatment of acute septic arthritis following total knee arthroplasty when the patient attempted full weight-bearing with the affected limb in a semiflexion position and twisted the knee. methods AND RESULTS: Successful treatment was provided with subsequent surgical debridement, removal of the loosened prosthesis, the application of systemic antibiotics, and a revision total knee arthroplasty utilizing a posteriorly stabilized prosthesis after adequate control of the infection. CONCLUSION: Soft-tissue protection from full weight-bearing of the knee during the treatment of an acute infection following total knee arthroplasty and timely removal of the loosened total knee prosthesis are recommended in order to prevent such a complication.- - - - - - - - - - ranking = 0.1keywords = ligament (Clic here for more details about this article) |
8/29. Reconstruction of the iliofemoral ligament with an artificial ligament for recurrent anterior dislocation of total hip arthroplasty.An 86-year-old woman underwent 4 revisions of hip arthroplasty and showed good position of both acetabular and femoral components. This was confirmed by roentgenographic measurements in the prone position. However, poor anterior acetabular covering after posterior inclination of the pelvis associated with lumbar kyphosis was observed in the standing position. Therefore, we reconstructed the iliofemoral ligament using a Leeds-Keio ligament to prevent anterior dislocation. At the 12-month follow-up evaluation, hip stability was confirmed, and the hip showed no further dislocation.- - - - - - - - - - ranking = 1keywords = ligament (Clic here for more details about this article) |
9/29. Calcification of intraocular hydrogel lens: evidence of dystrophic calcification.PURPOSE: To report and describe the surface calcification of three cases of implanted intraocular hydrogel lens. methods: Three surgically extracted hydrogel intraocular lenses were studied by light and transmission electron microscopy as well as by energy dispersion X-ray microanalysis. RESULTS: The lens surfaces were covered by granular deposits of calcium phosphate, clearly delineated by von Kossa and alizarin stains for calcium. Transmission electron microscopy showed the deposits to be located within the superficial lens material to a depth of 7 microm and to be associated with what appear to be traces of cellular material including basement membrane and plasmalemma. To the authors' knowledge there has been only one other transmission electron microscopic study. Energy dispersion X-ray microanalysis showed the deposits to contain calcium and phosphorous in all cases. CONCLUSIONS: This study confirms and extends the previous reports of five cases of calcification of hydrogel intraocular lenses. The exact mechanism of calcification remains obscure but evidence suggesting cell-mediated dystrophic calcification of the lens surface is presented. Further study is required to monitor the incidence and development of this phenomenon.- - - - - - - - - - ranking = 0.00081821851628658keywords = membrane (Clic here for more details about this article) |
10/29. Surgical management of vaginal vault prolapse in a woman with a neovagina and pelvic kidneys.BACKGROUND: women with Mayer-Rokitansky-Kuster-Hauser syndrome have congenital absence of the uterus and upper two-thirds of the vagina, which is frequently accompanied by skeletal and renal anomalies. Mechanical dilation or surgical creation of a vagina allows for function but does not provide endopelvic fascial support of the vagina. Vaginal prolapse may occur. CASE: A 32-year-old woman presented with pelvic kidneys and a 5-year history of prolapse of her mechanically created neovagina. She underwent a sacrospinous ligament suspension with a cadaveric fascia lata bridge. The apex of the neovagina was 5 cm above the hymen 30 months postoperatively. CONCLUSION: An allograft colpopexy to the sacrospinous ligament is an effective method of surgical treatment of women with a prolapsed shortened vagina and an inaccessible presacral space.- - - - - - - - - - ranking = 0.2keywords = ligament (Clic here for more details about this article) |
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