Robotic Versus Laparoscopic Resection of Large Adrenal Tumors

Background

Although recent studies have shown the feasibility and safety of robotic adrenalectomy, an advantage over the laparoscopic approach has not been demonstrated. Our hypothesis was that the use of the robot would facilitate minimally invasive resection of large adrenal tumors.

Methods

Adrenal tumors ??5?cm resected robotically were compared with those removed laparoscopically from a prospective institutional review board-approved adrenal database. Clinical and perioperative parameters were analyzed using t and chi-square tests. All data are expressed as mean?±?standard error of mean.

Results

There were 24 patients with 25 tumors in the robotic group and 38 patients with 38 tumors in the laparoscopic group. Tumor size was similar in both groups (6.5?±?0.4 [robotic] vs 6.2?±?0.3?cm [laparoscopic], P?=?.661). Operative time was shorter for the robotic versus laparoscopic group (159.4?±?13.4 vs 187.2?±?8.3 min, respectively, P?=?.043), while estimated blood loss was similar (P?=?.147). The conversion to open rate was less in the robotic (4%) versus the laparoscopic (11%) group; P?=?.043. Hospital stay was shorter for the robotic group (1.4?±?0.2 vs 1.9?±?0.1?days, respectively, P?=?.009). The 30-day morbidity was 0 in robotic and 2.7% in laparoscopic group. Pathology was similar between groups.

Conclusions

Our study shows that the use of the robot could shorten operative time and decrease the rate of conversion to open for adrenal tumors larger than 5?cm. Based on our favorable experience, robotic adrenalectomy has become our preferred minimally invasive surgical approach for removing large adrenal tumors.     

Reconstruction of the interosseous ligament of the forearm reduces load on the radial head in cadavers

Excision of the radial head after fracture may be complicated by longitudinal radio-ulnar instability (Essex-Lopresti lesion) if the forearm interosseous ligament has also been torn. In such cases proximal migration of the radius occurs, and ulnar impaction at the wrist and radiocapitellar contact at the elbow may impair function. Although metal radial head arthroplasties are now used for irreparable radial head fractures, the long-term clinical outcome may still be unsatisfactory because of excessive radiocapitellar load causing pain. Interosseous ligament reconstruction might improve outcome by restoring normal load transfer from the radius to ulna, but the biomechanical effect of reconstruction has not been reported. This study evaluated forearm load transfer following interosseous ligament reconstruction with an Achilles tendon allograft in a cadaveric model with the radial head intact. Interosseous ligament reconstruction reduced proximal radius loading by transferring force to the proximal ulna, but force transfer by the reconstruction was only half that by the intact ligament.     

Peroxisome proliferator-activated receptor-alpha agonist treatment in a transgenic model of type 2 diabetes reverses the lipotoxic state and improves glucose homeostasis

Abnormalities in insulin action are the characteristics of type 2 diabetes. Dominant-negative muscle-specific IGF-I receptor (MKR) mice exhibit elevated lipid levels at an early age and eventually develop type 2 diabetes. To evaluate the role of elevated lipids in the progression of the diabetic state, MKR mice were treated with WY14,643, a peroxisome proliferator-activated receptor (PPAR)-alpha agonist. WY14,643 treatment markedly reduced serum fatty acid and triglyceride levels within a few days, as well as muscle triglyceride levels, and subsequently normalized glucose and insulin levels in MKR mice. Hyperinsulinemic-euglycemic clamp analysis showed that WY14,643 treatment enhanced muscle and adipose tissue glucose uptake by improving whole-body insulin sensitivity. Insulin suppression of endogenous glucose production by the liver of MKR mice was also improved. The expression of genes involved in fatty acid oxidation was increased in liver and skeletal muscle, whereas gene expression levels of hepatic gluconeogenic enzymes were decreased in WY14,643-treated MKR mice. WY14,643 treatment also improved the pattern of glucose-stimulated insulin secretion from the perfused pancreata of MKR mice and reduced the beta-cell mass. Taken together, these findings suggest that the reduction in circulating or intracellular lipids by activation of PPAR-alpha improved insulin sensitivity and the diabetic condition of MKR mice.     

Trabecular bone density of male human cervical and lumbar vertebrae

The objective of this study was to determine the bone mineral density (BMD) of cervical vertebrae and correlate with the lumbar spine. Fifty-seven young adult healthy male volunteers, ranging from 18 to 41 years of age, underwent quantitative computed tomography (QCT) scanning of C2-T1 and L2-L4 vertebrae. To account for correlations, repeated measures techniques were used to compare data as a function of spinal level and region. Linear regression methods were used (+/-95% CI) to compare data as a function of spinal level and region. The mean age and body height were 25.0 +/- 5.8 years and 181.0 +/- 7.6 cm. BMD decreased from the rostral to caudal direction along the spinal column. Grouped data indicated that the neck is the densest followed by the first thoracic vertebra and low back with mean BMD of 256.0 +/- 48.1, 194.3 +/- 44.2, and 172.2 +/- 28.4 mg/cm(3), respectively; differences were statistically significant. While BMD did not vary significantly between the three lumbar bodies, neck vertebrae demonstrated significant trends. The matrix of correlation coefficients between BMD and spinal level indicated that the relationship is strong in the lumbar (r = 0.92-0.96) and cervical (r = 0.73-0.92) spines. Data from the present study show that the trabecular bony architecture of the neck is significantly different from the low back. These quantitative BMD data from a controlled young adult healthy human male volunteer population may be valuable in establishing normative data specifically for the neck. From a trabecular bone density perspective, these results indicate that lumbar vertebrae cannot act as the best surrogates for neck vertebrae. Significant variations in densities among neck vertebrae, unlike the low back counterpart, may underscore the need to treat these bones as different structures.     

Modeling changes in intervertebral disc mechanics with degeneration

Mechanical response of the spine to various dynamic loading conditions can be analyzed by way of in vitro and in vivo studies. Ethical concerns, interpretation of conclusions reached in animal studies, and lack of detailed stress distributions in the disc components are the major disadvantages of relying solely on in vivo studies. Intraspecimen variability, difficulty in including muscle activity, and inability to mimic fluid exchange into the disc during unloading are some of the disadvantages of in vitro models. The poroelastic finite element models can provide a method of understanding the relationship between biomechanical performance of the disc due to cyclic loading and disc degeneration. A poroelastic finite element model, including regional variation of strain-dependent permeability and osmotic pressure, was used to study the effect of disc degeneration on biomechanical properties as well as propagation of failure in the disc components when cyclic loading was applied to the lumbar disc. The results predicted that healthy discs were much more flexible than degenerated discs, and the disc stiffness decreased with increasing the number of load cycles independent of degenerative condition. Failure was found to progress as the drained elastic properties of the disc components decreased due to the presence of failure. Poroelastic finite element modeling, including strain-dependent permeability and osmotic pressure, is the most advanced analytical tool currently available that can be used to understand how cyclic loading affects the biomechanical characteristics of a degenerated lumbar disc. However, a complete understanding of behavior of the intervertebral disc will ultimately be achieved only with use of a combination of computational models together with in vitro and in vivo experimental methods. Finite element models of discs with varying degrees of disc degeneration will help clinicians understand the initiation and progression of disc failure and degeneration and will assist in the development of approaches to stimulate the regeneration of disc tissues.     

Tube pedicle flap in the management of a Grade III C lower limb injury.

Salvage of a Grade III C lower limb injury is a challenging problem. Apart from microsurgical revascularisation, they frequently need soft tissue coverage procedures. Due to the magnitude of the injury, local flaps from adjacent tissues may not be available and microsurgical free flaps are the flaps of choice. We present an instance where the defect in the middle third of a revascularised leg was covered by a tube pedicle flap raised from the groin and transferred, with the wrist as the carrier. This was chosen because of the below knee amputation on the opposite side combined with long segment circumferential loss of skin in the affected extremity and paucity of vein graft sources. Thus the reconstruction of a limb which was saved by microsurgery was completed by tube pedicle flap. In exceptional circumstances 'old' techniques are still useful.     

Type II odontoid fracture from frontal impact: case report and biomechanical mechanism of injury

The authors report a case of Type II odontoid fracture from a frontal impact sustained in the crash of a late-model motor vehicle. They discuss the biomechanical mechanisms of injury after considering patient demographic data, type and use of restraint systems including seatbelt and airbags, crash characteristics, and laboratory-based experimental studies. Multiple factors contributed to the Type II odontoid fracture: the patient's tall stature and intoxicated state; lack of manual three-point seat belt use; obliqueness of the frontal impact; and the most likely preflexed position of the head-neck complex at the time of impact, which led to contact of the parietal region with the A-pillar roof-rail area of the vehicle and resulted in the transfer of the dynamic compressive force associated with lateral bending. Odontoid fractures still occur in individuals involved in late-model motor vehicle frontal crashes, and because this injury occurs secondary to head impact, airbags may not play a major role in mitigating this type of trauma to an unrestrained occupant. It may be more important to use seat belts than to depend on the airbag alone for protection from injury.     

Pharmacologic C5-complement suppression reduces blood loss during on-pump cardiac surgery

BACKGROUND: Inflammation contributes to morbidity following on-pump cardiac surgery. Complement activation during cardiopulmonary bypass has been associated with the postoperative bleeding and tissue injury. This study examines the pharmacology and impact on blood loss of complement C5 suppression with pexelizumab in patients undergoing cardiac surgery with cardiopulmonary bypass. METHODS: Pexelizumab, a humanized monoclonal antibody single-chain fragment that binds to the human C5 complement component, was studied in a Phase II multicentered clinical trial. CABG (n = 800) and CABG with concomitant valve surgery (n = 114) patients were evaluated. Patients were randomized to either: pexelizumab bolus (2.0 mg/kg) + placebo infusion; pexelizumab bolus (2.0 mg/kg) + pexelizumab infusion (0.05 mg/kg/hour for 24 hours); or placebo bolus + placebo infusion. Pharmacology, chest tube drainage, and transfusion requirements were assessed. RESULTS: Mean maximum pexelizumab serum concentration was similar for bolus and bolus + infusion-treated patients. Complement-dependent serum hemolytic activity was completely suppressed within 1 hour following pexelizumab bolus, however, suppression was maintained for a longer duration in the bolus + infusion compared to the bolus-only treated patients. A reduction in chest tube drainage was observed for all pexelizumab-treated patients, although transfusion of blood products was similar across all study groups. CONCLUSION: Pexelizumab administration inhibits complement-dependent hemolytic activity and is associated with a reduction in postoperative chest tube drainage in patients undergoing cardiac surgery requiring cardiopulmonary bypass. Further, clinical studies are needed to assess the value of complement attenuation in this setting.