PubMed Health⌕ Search

Biomedical subjects

W B Rockwell

Publications and source records attributed to W B Rockwell.

At least 19 recordsLinked to original sources
PubMed2000

Autogenous arterial bypass grafts: durable patency and limb salvage in patients with inframalleolar occlusive disease and end-stage renal disease.

OBJECTIVE: The purposes of this study were to determine whether autogenous arterial grafts to distal pedal arteries improve the patency of grafts and limb salvage in patients with end-stage renal disease and nonhealing ischemic wounds and to better define the indications for autogenous arterial grafts. DESIGN: A review of consecutive patients with end-stage renal disease undergoing autogenous arterial grafts from 1994 through 1999 was carried out. The setting was a university hospital. All 11 patients with end-stage renal disease and nonhealing, ischemic wounds (stage IV SVS-ISCVS classification) undergoing autogenous arterial grafting from 1994 to 1999 were evaluated. Noninvasive studies confirmed inadequate perfusion pressures in all patients. Pre-bypass arteriography identified no major arteries patent at the level of the malleolus, with reconstitution of only a distal or branch pedal or plantar vessel less than 1 mm in diameter. Five patients with patent tibial vessels to just above the ankle underwent bypass surgery with autogenous arterial grafts alone. Six patients also had proximal occlusive disease that required grafts longer than the autogenous arterial grafts; in each of these six patients, an autogenous vein graft proximal to the autogenous arterial graft was placed through use of a composite technique. Inflow was from the common femoral artery in one patient, the popliteal artery in five patients, and a tibial artery in five patients. Outflow was to the medial plantar artery in five patients, the distal dorsalis pedis artery in three patients, the lateral plantar artery in two patients, and the superficial arch in one patient. The conduit was the subscapular artery in four patients, the deep inferior epigastric artery in four patients, the superficial inferior epigastric artery in two patients, and the radial artery in one patient. The main outcome measures were assisted primary graft patency and functional limb salvage rate. RESULTS: Follow-up ranged from 6 to 63 months (mean, 20 months); graft patency was determined by means of duplex scanning. All 11 patients are alive, and nine grafts are patent, including three after revision for graft stenosis. Assisted primary patency was 82% at 3 years. All nine patients with patent grafts remained ambulatory and had healed wounds or limited forefoot amputations. CONCLUSION: Autogenous arterial grafts were effective in treating limb-threatening ischemia in patients with end-stage renal disease and inframalleolar arterial insufficiency. Graft patency and limb salvage rates were higher than those reported for autogenous vein graft in these patients. Autogenous arterial grafting may therefore prove to be an effective alternative to autogenous vein grafting in selected patients.

Arterial Occlusive Diseases↗
PubMed2000

Extensor tendon: anatomy, injury, and reconstruction.

Although seemingly simple in its anatomy and function, the extensor mechanism of the hand is actually a complex set of interlinked muscles, tendons, and ligaments. A thorough understanding of the extensor anatomy is required to understand the consequences of injury at various levels. Reconstructive options must restore normal function. Whereas primary repair of anatomic structures is frequently possible in acute injury, it is rarely possible in chronic situations. Technically exacting procedures may be necessary to restore function.

Acute Disease↗
PubMed1999

Ganglions of the proximal interphalangeal joint.

Ganglion cysts-the most common hand tumors-usually affect women in their twenties and thirties. The cause of these cysts is unknown, although trauma has been postulated as an inciting factor. Ganglions occur most commonly at the dorsal and palmar wrist. However, ganglions of the proximal interphalangeal (PIP) joint are rare. Four patients with PIP joint ganglions were recently treated at our institution. Three received aspiration and one received operative therapy, all with good results. All four patients were older than 65 years.

Aged↗
PubMed1998

Postmastectomy lymphedema management: evolution of the complex decongestive therapy technique.

Extremity lymphedema, historically a surgical disease, is now successfully managed with a physical therapy regimen called complex decongestive therapy, which originated in Europe. Herein we present a historical perspective on the understanding and treatment of lymphedema. We review a series of 20 patients with postmastectomy arm edema who were treated with complex decongestive therapy and were followed for 6 months. On average these patients achieved a stable 73% reduction in arm circumference.

Arm↗
PubMed1998

Breast capsule persistence after breast implant removal.

Breast implant capsules are a foreign body immune response to breast implants. It has been proposed that capsulectomy after breast implant removal was unnecessary, as the body resorbs the capsule when the implant, the impetus for the foreign body response, is removed. We report eight women with persistent capsules 10 months to 17 years after silicone breast implant removal.

Adult↗
PubMed1997

Anti-ICAM-1 antibodies protect allografts against microvascular and parenchymal cell damage.

Anti-ICAM-1 (anti-intercellular adhesion molecule-1) monoclonal antibodies (CD54) were tested for treating composite tissue allografts in the rat hindlimb-cremaster transplantation model for intravital microcirculatory studies. Twenty-four transplantations were carried out across major histocompatibility barriers between Lewis-Brown Norway and Lewis rats. Isograft control transplants were compared to nontreated allograft control transplants and to allografts treated with 1 mg/kg of anti-ICAM-1 monoclonal antibodies. At 24 and 72 hours, microcirculatory vessel diameters, red blood cell velocities, functional capillary perfusion, endothelial edema index, and leukocyte-endothelial interactions were measured. At 24 and 72 hours, the number of sticking leukocytes, sticking lymphocytes, transmigrating leukocytes, and the endothelial edema index in the treated allografts were significantly decreased more than in the other 2 groups (p < .05 for all variables). Anti-ICAM monoclonal antibodies significantly reduced leukocyte-endothelial interactions, protecting the allografts from acute microvascular and parenchymal injury.

Animals↗
PubMed1997

Clinical use of leeches in reconstructive surgery.

Although medicinal bloodletting with leeches is a practice that dates back 3500 years, leeches have been used in reconstructive surgery for only the past 35 years. In this article, the indications, mechanisms of action, and guidelines for using leeches in reconstructive surgery are reviewed.

Animals↗
PubMed1995

Acute adverse effects of blunt adventitial stripping.

The adventitia is routinely removed from small arteries before the anastomosis, but the microcirculatory response to this maneuver has not been documented. We have used a rat cremaster muscle flap model for intravital microscopy to compare at the microcirculatory level the effect of blunt (n = 18) and sharp (n = 18) adventitial removal with unmanipulated control arteries (n = 18). Blunt stripping resulted in transient but significant reductions in the red cell velocity (50%, p < 0.05) and capillary perfusion (91%, p < 0.05). Sharp dissection did not affect red cell velocity; however, capillary perfusion was transiently reduced by 25% (p < 0.05). In this study, sharp adventitial dissection was found to be a less harmful method of small arteries preparation for microvascular anastomosis.

Anastomosis, Surgical↗
PubMed1993

Soft tissue reconstruction. Coverage of hand injuries.

The complexity of the hand necessitates careful assessment of an injury. Wound coverage requires careful appraisal of the tissue available for coverage and consideration of its functional and cosmetic aspects. The simplest yet most appropriate flap should be chosen. Local flaps can cover many wounds. Larger wounds may require significant debridement, which should be performed early using the pseudotumor technique. Free flap coverage is then indicated and should be completed within 3 days of injury if no extenuating circumstances exist.

Finger Injuries↗
PubMed1992

Simultaneous dorsal trapezium-scaphoid and trapezoid-carpal subluxations.

Trapezium-scaphoid-trapezoid subluxations and trapezoid-capitate-scaphoid-trapezium subluxations or dislocations are rare. A single case combining these two injuries is presented. The mechanism may have been axial loading in extension or flexion. Two modes of treatment, closed and open, were needed for the two injuries.

Adolescent↗
PubMed1991

Demonstration of a direct role for myosin light chain kinase in fibroblast-populated collagen lattice contraction.

Mixing feed fibroblasts with soluble collagen and serum-supplemented culture medium at 37 degrees C results in the entrapment of cells within the polymerizing collagen matrix. This cellular-collagen complex is referred to as a fibroblast-populated collagen lattice (FPCL). In time, this FPCL undergoes a reduction in size called lattice contraction. The proposed mechanism for lattice contraction is cellular force produced by cytoplasmic microfilaments which organize collagen fibrils compacting the matrix. When the regulatory subunits of myosin, myosin light chains, are phosphorylated by myosin light chain kinase (MLCK), myosin ATPase activity is increased and actin-myosin dynamic filament sliding occurs. Elevated levels of myosin ATPase are required for maximal lattice contraction. Cholera toxin inhibits lattice contraction by increasing intracellular levels of cAMP. It is proposed that increased cytoplasmic concentrations of cAMP promote phosphorylation of MLCK, the enzyme important for maximizing myosin ATPase activity. Phosphorylating MLCK in vitro inhibits activity by decreasing its sensitivity to calcium-calmodulin complex. A decrease in MLCK activity would result in lower levels of myosin ATPase activity. MLCK, purified from turkey gizzard, was subjected to limited proteolytic digestion to produce calmodulin-independent-MLCK. The partially digested kinase does not require calcium-calmodulin for activation. Independent-MLCK is not subject to inhibition by phosphorylation. The electroporetic inoculation of independent-MLCK into fibroblasts before FPCL manufacture produced enhanced lattice contraction. Lattice contraction, in the presence of cholera toxin, was restored to normal levels by the prior electroporetic introduction of independent-MLCK. These findings support the hypothesis that increases in cAMP hinder lattice contraction by a mechanism involving inhibition of MLCK and myosin ATPase.

Animals↗
PubMed1991

An ibuprofen-antagonized plasmin inhibitor released by human endothelial cells.

Serum-free culture medium harvested from endothelial cell monolayer cultures derived from human scars and dermis was examined for inhibition of fibrinolysis using a fibrin plate assay. Human cultured fibroblasts and smooth muscle cells did not produce any detectable inhibitory activity. The inhibitor is spontaneously released from the cultured endothelial cells over time. In the fibrin plate assay of plasmin-induced fibrinolysis, one nonsteroidal antiinflammatory (NSAI) drug, ibuprofen, was demonstrated to antagonize the inhibition of fibrinolysis. The antagonistic activity of ibuprofen appears unrelated to its NSAI drug activity because other NSAI drugs such as indomethacin and tolmetin have minimal antagonistic activity. Heating the cultured endothelial cells to 42 degrees C stimulates greater release of the inhibitor in a shorter period of time. This plasmin inhibitor, which is produced by endothelial cells, may contribute to postburn vascular occlusion, leading to secondary progressive necrosis in burn-traumatized patients.

Antifibrinolytic Agents↗
PubMed1990

Ibuprofen in acute-care therapy.

Ibuprofen is a potent cyclooxygenase inhibitor known to reduce the production of arachidonic acid metabolites. Prostacyclin and thromboxane are well-studied metabolites that play a prominent role in inflammation. Many of the effects of ibuprofen can be linked to its anti-inflammatory properties. Beneficial results from ibuprofen therapy have been documented, and more widespread use of the drug seems indicated. Conditions ranging from immunologic response to trauma and sepsis to postburn lung dysfunction to wound edema are improved by the use of ibuprofen. The fact that ibuprofen is effective in the various conditions detailed above, while other steroidal and nonsteroidal drugs are effective only in selective instances, increases the value of ibuprofen. Other properties of the drug, aside from its anti-inflammatory effects, are not as well studied and not as well known. Their importance, however, should not be overlooked. Superoxide radical tissue injury may be very important in acute injury and this phenomenon needs further study. In several studies ibuprofen has been shown to antagonize this type of injury. Similarly fibrinolysis inhibition is known to occur in burn wounds, but its role in other injuries is unknown. The antagonism of this inhibitor by ibuprofen maintains vascular patency. The clinical use of ibuprofen will increase as research further elucidates the mechanisms of tissue injury in acute situations and the many and varied mechanisms of action of ibuprofen.

Acute Disease↗