Comparative analysis of sodium coupled vitamin C transporter 2 in human osteoarthritis grade 1 and grade 3 tissues.

Background: Nutrient levels are known to influence the development of osteoarthritis (OA), presumably by modulating levels of matrix biosynthesis and degradation. These processes may be affected by ascorbic acid (AA), an antioxidant which acts as a cofactor for numerous biochemical reactions and is essential for post-translational modifications of collagen. In this study we examined the expression of SVCT2, the only known Sodium coupled vitamin C transporter isoform present in articular cartilage, in human articular cartilage explants derived from both normal and osteoarthritis articular cartilage.

Minocycline-induced black bone disease encountered during total knee arthroplasty.

Finding discolored bone intraoperatively can be confusing and concerning to orthopedic surgeons. Multiple causes of pigmented bone exist, including ochronosis, metabolic bone diseases, metal deposits, sequestrum, metastatic disease, and minocycline use. Bone quality is an important consideration in intraoperative decision making with respect to components and fixation options in total joint arthroplasty.

Wear performance of large-diameter differential-hardness hip bearings.

We hypothesized that differential-hardness hard-on-hard bearings would generate less wear debris compared with like-hardness metal-on-metal (M-o-M) bearings. We conducted wear testing on 3 types of large-diameter hard hip bearings: (1) contemporary cast-on-cast ("like" hardness) M-o-M; (2) differential-hardness M-o-M; and (3) differential-hardness ceramic-on-metal. A simulated gait profile ranging from 200 to 2000 N was applied to the bearings at a frequency of 1 Hz for 5 Mc.

Presentation of gamma-irradiated-in-air polyethylene wear in the form of a synovial cyst.

The increased wear of polyethylene sterilized with gamma irradiation in air has well been documented in the total knee arthroplasty literature. Our case report describes a patient with a well-functioning total knee replacement presenting with wear debris synovitis in the form of a large synovial cyst. We discuss this patient's preoperative evaluation, intraoperative findings, and postoperative outcome after synovectomy and polyethylene exchange.

Cementless S-ROM femoral component: effect of stem length on stability after extended proximal femoral osteotomy.

The extended proximal femoral osteotomy is becoming increasingly popular in revision total hip replacement. Our study was done to determine the femoral stem length required for stable fixation of a cementless femoral component after an extended proximal femoral osteotomy. Three lengths of the S-ROM femoral stem were implanted in paired cadaver femora and tested under torsional and axial loads.

Light microscopic and scanning electron microscopic retrieval analyses of implanted biomaterials retrieved from humans and experimental animals.

This paper reports analysis obtained from 200 implant cases retrieved from humans and submitted to the American Academy of Implant Dentistry Research Foundation, Medical College of Georgia implant retrieval center. The samples that were not decalcified were embedded in polymethylmethacrylate and examined with scanning electron microscopy and routine light, polarized, or Nomarski microscopy. Cases included both orthopedic and dental implants, as well as entire mandibles and portions of maxillae obtained at autopsy.

The biologic tissue responses to uncoated and coated implanted biomaterials.

Ultrastructural examination of the morphology and morphometry of the bone supporting uncoated titanium and ceramic implants was assessed in an experimental animal model involving 120 implants placed into the mandibles of 30 adult mongrel dogs. Further, preliminary morphologic and morphometric observations of the bone supporting uncoated and hydroxylapatite-coated endosteal titanium implants was evaluated in a second investigation involving 72 implants placed into the mandibles and maxillae of 6 additional dogs. A densely mineralized collagen fiber matrix was observed directly interfacing with uncoated implants.

Correlative experimental animal and human clinical retrieval evaluations of hydroxyapatite (HA)-coated and non-coated implants in orthopaedics and dentistry.

Retrieval analyses disclosed in vivo dissociation of HA in orthopaedic acetabular components, but excellent bone ingrowth into intact HA coatings on dental retrievals. Initial healing and the bone interface between HA-coated and non-coated implants in the posterior maxilla (Mx) and mandible (Md) was assessed in an animal model using light microscopy (LM), including confocal (CM) and Nomarski (NM) microscopy. Seventy-two implants (36 HA-coated; 36 non-coated) were placed into jaws of six dogs; half after extraction, half after 3 months healing.

Retrieval analyses of implanted biomaterials: light microscopic and scanning electron microscopic analyses of implants retrieved from humans.

We report analyses obtained from 135 implant cases retrieved from humans and submitted to the American Academy of Implant Dentistry Research Foundation--Medical College of Georgia Implant Retrieval Center. The undecalcified samples were embedded in polymethyl-methacrylate and examined with scanning electron microscopy and with routine light via polarized or Nomarski microscopy. Cases included both orthopedic and dental implants as well as entire mandibles obtained at autopsy.

Critical pathways: a means of managing the operating room.

Critical pathways help institutions in efficient and appropriate resource use to increase the quality of health care and minimize health care costs. However, many opportunities for pathway development and implementation are unexplored. This article delineates the development process for critical pathways and discusses the outcomes realized from use of the total joint pathway at the Medical College of Georgia, Augusta, GA.

In vivo evaluation of the biocompatibility of implanted biomaterials: morphology of the implant-tissue interactions.

Electron microscopic observations were made from tissues apposing titanium and ceramic root form and blade implants. The tissue was serially sectioned from the most coronal epithelium, through the gingival connective tissue, to the osseous support tissues, and directly to the most apical tissue support. Of the thousands of sections analyzed for each implant, 500 micrographs were routinely viewed for each of the implants analyzed by this study.

Ultrastructural analyses of the attachment (bonding) zone between bone and implanted biomaterials.

This report presents transmission electron and high voltage transmission electron microscopic observations of bone and associated remodeling tissues directly interfacing with endosteal dental implants. Undecalcified interfacial tissues were serially sectioned from mandibular samples encasing 60 implants placed into 30 dogs. Two-dimensional ultrastructural analyses and three-dimensional stereology showed that osteogenesis adjacent to dental implants is a dynamic interaction of osseous cells and a collagenous fiber matrix.

Total knee replacement in a patient with lupus anticoagulant.

The lupus anticoagulant is an acquired circulating anticoagulant that was first described in patients with systemic lupus erythematosus (SLE). This rare hematologic entity is seen in about 1% to 2% of the general population and about 10% to 35% of the patients with SLE. Although associated with a prolonged partial thromboplastin time (PTT), the lupus anticoagulant does not cause bleeding complications but may be associated with an increase in thromboembolic complications.

Composite morphology of the bone and associated support-tissue interfaces to osseointegrated dental implants: TEM and HVEM analyses.

Correlated transmission electron and high-voltage electron microscopic analyses examined the undecalcified bone and associated support tissues of 60 endosseous titanium blade and titanium and ceramic root-form implants in dogs. The implants supported fixed partial dentures for up to 2 years. Data obtained from this investigation suggest that a range of tissues, both mineralized and unmineralized, support osseointegrated dental implants.

Clinical use of a syndesmosis screw in stage IV pronation-external rotation ankle fractures.

The purpose of this study was to determine if biomechanical data obtained in studies on cadavers correlates with clinical results in the surgical treatment of stage IV pronation-external rotation (PER-IV) ankle fractures. We surgically treated 20 patients who sustained isolated PER-IV ankle injuries and followed 18 of the patients for an average of 2.5 years.

Acute gonococcal flexor tenosynovitis in an adolescent male with pharyngitis. A case report and literature review.

A 15-year-old boy had acute gonococcal flexor tenosynovitis of the middle finger associated with symptomatic gonococcal pharyngitis. The patient had a history of blunt trauma to the hand. The need for a careful history in any sexually active adolescent is emphasized.

The metal-backed patella. An invitation for failure?

Thirty-one cases of failed metal-backed patellar components requiring revision surgery are reviewed. Two modes of implant failure onset were noted. Within each group, delays in patient presentation and diagnosis of the failed component were encountered.

A quantitative assessment of degenerative changes acceptable in the unoperated compartments of knees undergoing unicompartmental replacement.

Thirty-five unicondylar knee arthroplasties were performed on 32 patients. In the unresurfaced compartments, degenerative cartilaginous changes were observed intraoperatively and recorded. The Outerbridge grading scale was used to assess the degree of arthritic change.

Surgical management of pulmonary disease due to Mycobacterium avium-intracellulare.

Of 131 patients with pulmonary infections due to Mycobacterium avium-intracellulare, 124 had excisional surgery plus chemotherapy. Seven had definitive thoracoplasties. Postoperative complications of various degrees developed in 24% of those who had surgery.