The microfracture technique for the treatment of articular cartilage lesions in the knee. A prospective cohort study

BACKGROUND: Microfracture is a frequently used technique for the repair of articular cartilage lesions of the knee. Despite the popularity of the technique, prospective information about the clinical results after microfracture is still limited. The purpose of our study was to identify the factors that affect the clinical outcome from this cartilage repair technique. METHODS: Forty-eight symptomatic patients with isolated full-thickness articular cartilage defects of the femur in a stable knee were treated with the microfracture technique. Prospective evaluation of patient outcome was performed for a minimum follow-up of twenty-four months with a combination of validated outcome scores, subjective clinical rating, and cartilage-sensitive magnetic resonance imaging. RESULTS: At the time of the latest follow-up, knee function was rated good to excellent for thirty-two patients (67%), fair for twelve patients (25%), and poor for four (8%). Significant increases in the activities of daily living scores, International Knee Documentation Committee scores, and the physical component score of the Short Form-36 were demonstrated after microfracture (p < 0.05). A lower body-mass index correlated with higher scores for the activities of daily living and SF-36 physical component, with the worst results for patients with a body-mass index of >30 kg/m(2). Significant improvement in the activities of daily living score was more frequent with a preoperative duration of symptoms of less than twelve months (p < 0.05). Magnetic resonance imaging in twenty-four knees demonstrated good repair-tissue fill in the defect in thirteen patients (54%), moderate fill in seven (29%), and poor fill in four patients (17%). The fill grade correlated with the knee function scores. All knees with good fill demonstrated improved knee function, whereas poor fill grade was associated with limited improvement and decreasing functional scores after twenty-four months. CONCLUSIONS: Microfracture repair of articular cartilage lesions in the knee results in significant functional improvement at a minimum follow-up of two years. The best short-term results are observed with good fill grade, low body-mass index, and a short duration of preoperative symptoms. A high body-mass index adversely affects short-term outcome, and a poor fill grade is associated with limited short-term durability.     

Jejunal perforation by a fish bone diagnosed by CT-Scan: report of two cases

The authors relate two cases of peritonitis secondary to jejunal perforation by a fish bone. Clinically, the first patient presented signs and symptoms of acute diverticulitis and the second had signs of duodenal perforation. In both cases, the diagnosis was made by the CT-scan revealing a linear radio-opaque object suggestive of a fish bone perforating the jejunum. At laparotomy of the first case, we found a perforation located above several loops of small bowel densely adhered to the nonabsorbable intra-abdominal mesh. Removal of the fish bone, suture of the jejunal perforation, washing and drainage of the abdominal cavity were performed. The mesh was removed and replaced by a polyglycolic acid mesh. In the second case, jejunal perforation occurred in an unaltered small bowel loop and a short intestinal resection was performed. The postoperative course was uneventful for both patients. These clinical cases allow us to discuss the several fish bone perforation site and our patients precipitating factors.     

Analysis of a protocol for an autologous blood transfusion program for total joint replacement surgery

This retrospective study analysed an autologous blood transfusion program for total joint replacement surgery. A group of 99 patients receiving autologous blood transfusion was compared with a control group of 55 patients. One-unit phlebotomies were done 14 and 7 days before surgery. The whole blood was transfused intraoperatively. Preoperative hemoglobin values were within the normal range for all patient groups except the female autologous blood group for which the mean value was 122 +/- 11.3 g/L. Due to perioperative hemodilution, the postoperative hemoglobin values were substantially lower than preoperative values for all groups. Mean intraoperative blood loss was similar for the autologous and control groups (650 to 750 ml). No adverse reactions were associated with the autologous transfusions and 74% of the autologous group received autologous blood only. From this analysis a 3-week, three-unit preoperative collection was proposed for future use. A standardized protocol will allow logistical ease and implementation of the program for various surgical procedures.     

Effects of Oxygen Supplementation on Injectable and Inhalant Anesthesia in C57BL/6 Mice

Oxygen supplementation is rarely considered when anesthetizing laboratory mice, despite reports that mice become profoundly hypoxic under anesthesia. Little is known about the effects of hypoxia on anesthetic performance. This article focuses on the effects of oxygen supplementation on physiologic parameters and depth of anesthesia in male and female C57BL/6 mice. Anesthesia was performed via common injectable anesthetic protocols and with isoflurane. Mice anesthetized with injectable anesthesia received one of 3 drug protocols. Low-dose ketamine/xylazine (100/8 mg/kg) was chosen to provide immobilization of mice, suitable for imaging procedures. Medium-dose ketamine/xylazine/acepromazine (100/10/1 mg/kg) was chosen as a dose that has been recommended for surgical procedures. High-dose ketamine/xylazine/acepromazine (150/12/3 mg/kg) was chosen after pilot studies to provide a long duration of a deep plane of anesthesia. We also tested the effects of oxygen supplementation on the minimum alveolar concentration (MAC) of isoflurane in mice. Mice breathed supplemental 100% oxygen, room air, or medical air with 21% oxygen. Anesthetized mice that did not receive supplemental oxygen all became hypoxic, while hypoxia was prevented in mice that received oxygen. Oxygen supplementation did not affect the MAC of isoflurane. At the high injectable dose, all mice not receiving oxygen supplementation died while all mice receiving oxygen supplementation survived. At low and medium doses, supplemental oxygen reduced the duration of the surgical plane of anesthesia (low dose with oxygen: 22 ± 14 min; low dose without supplementation: 29 ± 18 min; medium dose with oxygen: 43 ± 18 min; medium dose without supplementation: 61 ± 27 min). These results suggest that mice anesthetized with injectable and inhalant anesthesia without supplemental oxygen are routinely hypoxic. This hypoxia prolongs the duration of anesthesia with injectable drug protocols and affects survival at high doses of injectable anesthetics. Because of variable responses to injectable anesthetics in mice, oxygen supplementation is recommended for all anesthetized mice.

Anesthesia is frequently required for mice used in biomedical research, but anecdotal communications suggest that mice receive significantly less anesthetic monitoring and supportive care than do other research species. Monitoring of anesthetized mice is often minimal due to lack of specialized monitoring equipment, and the fact that many rodent surgeries are performed by a single person who acts as both surgeon and anesthetist. Supportive care during anesthesia is limited by a lack of supporting experimental evidence. The lack of monitoring and supportive care may increase the mortality rate in anesthetized mice.Previous studies have shown that mice anesthetized with both inhalant and injectable anesthetics without supplemental oxygen become profoundly hypoxic.^{1,6,8,9,19,26,39,41} While mice in these studies appear to recover normally from anesthesia, little is known about the effects of hypoxia on physiologic parameters, anesthetic depth, and perioperative mortality. Respiratory complications, including hypoxia and hypoventilation, are second only to cardiovascular complications as a cause of perioperative mortality in veterinary species, and in humans, hypoxemia accounts for over 50% of deaths under anesthesia.⁴ To mitigate the risk of hypoxia under anesthesia, oxygen supplementation is commonly provided to anesthetized humans and animals, but is rarely provided to mice in research settings.^6,19All anesthetics affect respiratory function; ketamine and isoflurane are particularly known to cause respiratory depression in mice and rats by impairing the normal physiologic responses to hypoxemia and hypercapnia.^{9,12,20,23,28} The peripheral chemoreceptors, primarily in the carotid body, normally sense dropping arterial partial pressure of oxygen (PaO₂) while central chemoreceptors located in the medulla sense changes in pH and rising partial pressure of carbon dioxide (PaCO₂).^22,23,29,40 Both sets of chemoreceptors compensate by initiating increases in respiratory rate and tidal volume.^{23,28,31,34,40} Injectable and inhalant anesthetic agents depress the function of these chemoreceptors, preventing the increases in respiration that compensate for hypoxia and hypoventilation.^22,29Pulse oximetry is commonly used to monitor peripheral oxygen saturation and detect the presence of hypoxia. Pulse oximeters use the difference in light absorption of oxygenated hemoglobin and deoxygenated hemoglobin in arterial blood to provide an estimate of arterial oxygen content, abbreviated as SpO₂.¹⁷ An SpO₂ of less than 90% to 95% generally corresponds to a PaO₂ of less than 60 to 80 mm Hg, which is considered hypoxic in most species of mammals.^7,17 Because of the small size of mice, species-specific pulse oximetry equipment is necessary to obtain this measurement. Therefore, measurement of SpO₂ in anesthetized mice is not routinely performed, meaning that hypoxia under anesthesia generally goes unrecognized, and is likely more common than is appreciated by our field.The purpose of this study was to confirm that mice become hypoxic after receiving a ketamine/xylazine based anesthetic admixture or isoflurane, which are commonly used anesthetics in mice and to investigate the effects of oxygen supplementation on anesthetic depth, physiologic values, and anesthetic requirements in these mice.^9,35 We hypothesized that mice not receiving supplemental oxygen would be hypoxic, as indicated by lower SpO₂ while anesthetized, and that supplemental oxygen would correct this hypoxia. We also hypothesized that oxygen supplementation would increase the doses of injectable and inhalant anesthesia necessary to maintain mice at a surgical plane of anesthesia.     

Gift wrapping ourselves: the final gift exchange

OBJECTIVE: This qualitative study examines the "final gift exchange" process by which older adults give cherished possessions in return for lasting appreciation. METHODS: We interviewed 54 middle- and upper-middle-class people (39 women) aged 50-90 who had to dispose of personal objects when moving to smaller residences. RESULT: We used Goffman's spiraling strategy in our analysis of people's reports of disposing of personal possessions. We identified three salient dimensions (family, economy, and self) of this process and created a heuristic describing eight ideal-type gift exchange scenarios by categorizing objects as valued or not valued by family and the economy as well as being an important aspect of the gift giver's material self. DISCUSSION: By applying the heuristic, we observed that a lack of shared definitions of the meaning and value of objects created dilemmas in disposing of personal objects, particularly those connected to a person's material self. We also offer suggestions for making the process go more smoothly, such as inquiring about the preferences of others and telling stories associated with objects to create shared definitions of the objects' significance to the giver and/or to family history.     

Intestinal over-expression of iron transporters induces iron overload in birds in captivity

Hereditary hemochromatosis (HH) is a frequent genetic disease of older subjects of northern European descent. It is characterized by increased iron absorption and severe iron overloading in parenchymal organs. A similar disturbance of iron metabolism occurs in specific animal species in captivity. To address the key features leading to high absorption and thus to iron overload in these animals, we have studied the two iron transport proteins DMT1 and Ireg1 in the best-known susceptible species, the mynah bird. Here, we show that these birds have a high expression of DMT1 in the duodenum and also a strikingly high expression of Ireg1 along the whole small intestine. We believe that the iron accumulation in susceptible species only occurs in captivity because of a genotypic adaptation to their natural environment, where contrary to captivity, dietary iron is hardly available. The Caucasian population carrying mutations leading to iron overload today may have also benefited from the genetic advantage of up-regulating iron transport millennia ago, when dietary iron was scarce.     

Thoracic splenosis presenting with hemoptysis.

Thoracic splenosis (post-traumatic autotransplantation of splenic tissue) is rare and generally asymptomatic. We report a patient with thoracic splenosis presenting with repeated hemoptysis. The blood supply of the hypervascular splenic transplants originated from a bronchial and an intercostal artery. Hemoptysis improved after surgical exeresis of splenosis. Recognizing splenosis presenting with hemoptysis is important, since percutaneous embolotherapy could be hazardous because of the risk of ectopic splenic tissue infarction.     

Relative value of adjuvant nephrectomy in metastatic renal cell carcinoma

Treatment results were evaluated by 101 cases of kidney-cell carcinomas, and the relative importance of adjunctive nephrectomy discussed. Radial nephrectomy was done in 28.7% and palliative (predominantly adjunctive), in 38.6% of the patients. Postoperatively died 7.6% of the nephrectomized patients. 13.8% of the radically operated survived more than 5 years. The average survival time of the palliatively nephrectomized patients was 12.9 months; it was principally independent of hormonal or cytostatic adjunctive therapy. Furthermore, a case of complete regression of multiple pulmonal metastases after nephrectomy is reported.