Intraosseous myolipoma of the calcaneus

A man in his 40s presented with an incidental finding of an osteolytic bone lesion. He sustained an ankle injury while inline skating, fracturing his lateral malleolus. Besides the fracture, radiographic imaging on the day of the injury incidentally revealed a well-defined solitary osteolytic lesion with a sclerotic rim within the right calcaneus. MRI showed an intraosseous, fat-containing lesion with focal contrast enhancement, assessed as an intraosseous lipoma with central necrosis. In the pathological analysis of a sample of the lesion an intraosseous myolipoma of the calcaneus was found-an unexpected and extraordinary finding. To prevent pathological fracturing, curettage and bone grafting were performed using autologous iliac crest bone in combination with allogenous bone chips.

Fish-like aquatic propulsion studied using a pneumatically-actuated soft-robotic model

Fish locomotion is characterized by waves of muscle electrical activity that proceed from head to tail, and result in an undulatory pattern of body bending that generates thrust during locomotion. Isolating the effects of parameters like body stiffness, co-activation between the right and left sides of the body, and frequency on thrust generation has proven to be difficult in live fishes. We use a pneumatically-actuated fish-like model to investigate how these parameters affect locomotor force generation. We measure thrust as well as side forces and torques generated during propulsion. Using a statistical linear model we examine the effects of input parameter combinations on thrust generation. We show that both stiffness and frequency substantially affect swimming kinematics, and that there are complex interactive effects of these two parameters on thrust. The stiffer the backbone the more impact that increasing frequency has on thrust production. For stiffer models, increasing frequency resulted in higher values for both thrust and lateral forces. Large side forces reduce swimming efficiency but this effect could be mitigated by decreasing undulatory wavelength and allowing appropriate phasing of left and right body movements to reduce amplitudes of side force.

Pathological fracture of the femoral neck following septic coxitis and chronic osteomyelitis: a potential complication of Lemierre's syndrome

We portray the case of a 16-year-old girl who was initially admitted to the paediatric emergency department with non-specific symptoms of a severe cold and was first treated symptomatically on an ambulatory basis. Within 6 days she developed the full clinical picture of Lemierre's syndrome with the extraordinary manifestation of involvement of her right hip. Despite an interdisciplinary coordinated treatment as well as surgical therapy, a full-blown sepsis evolved within a short time period and resulted in almost 2 months of intensive care. While the primary focus could be successfully controlled, a progressive avascular necrosis of the right proximal femur developed on the basis of a chronic osteomyelitis. This finally led to a pathological fracture of the femoral neck. After excluding the possibility of an enduring bacterial infection, the fracture was treated with a total hip replacement.

Laparoscopic management of gastric diverticula

Gastric diverticular are rare and usually are diagnosed incidentally on radiographic examination. Surgical treatment, consisting of simple excision or inversion of the diverticulum, has been reserved for patients with proven symptoms or complications. These procedures have typically required laparotomy, but with the development of advanced endoscopic techniques, a minimally invasive approach may be appropriate. The authors report two cases of gastric diverticula managed laparoscopically and review the literature related to this entity. Between 1993 and 1996, two patients were evaluated for dyspepsia-like gastrointestinal complaints. Both patients were found to have a gastric diverticulum on a contrast study, and one diverticulum was also seen on upper endoscopy. Laparoscopic resection was undertaken in both cases. Flexible gastroscopy was performed intraoperatively to help localize the diverticulum, which was resected with an endoscopic stapling device. Nissen fundoplication was performed in conjunction with the diverticulectomy in the second patient for gastroesophageal reflux. Both procedures were completed laparoscopically without complications. The postoperative course was uneventful in both patients. At long-term follow-up, the patients are asymptomatic. This experience indicates that laparoscopic resection of symptomatic gastric diverticula is a feasible alternative to laparotomy. A prospective analysis to verify the safety and efficacy of this procedure should be done.

Laparoscopic intraperitoneal onlay inguinal herniorrhaphy

BACKGROUND

This study presents intermediate follow-up data on a randomized prospective series of patients undergoing either a modified laparoscopic intraperitoneal onlay mesh herniorrhaphy (IPOM) or conventional anterior inguinal herniorrhaphy (CH).

METHODS

All patients from two university affiliated hospitals with primary or recurrent inguinal hernias were recruited for randomization to either the IPOM technique utilizing a meshed expanded polytetrafluorethylene (ePTFE) soft tissue patch or CH. Follow-up data were gathered from postoperative clinic visits and telephone and mail surveys.

RESULTS

Previously reported early recurrence and complication rates at a mean follow-up of 8 months were 1 of 30 (3%) and 5 of 30 (17%) for IPOM, and 2 of 28 (7%) and 5 of 28 (18%) for CH. Intermediate follow-up with 50 (23 IPOM and 27 CH) of the original 58 patients (86%) at a mean of 41 months reveals a recurrence rate of 10 of 23 (43%) for the IPOM group and 4 of 27 (15%) for the CH group (P = 0.053). Five delayed complications occurred in 4 IPOM patients (port site hernia 4, painful neuroma 1), while 2 delayed complications (unilateral testicular atrophy 2) occurred in 2 patients in the CH group. One IPOM versus 5 CH patients subsequently developed previously unrecognized contralateral hernias. There was 1 death unrelated to previous herniorrhaphy in each group.

CONCLUSIONS

IPOM recurrence rates (43%) at a mean follow-up of 41 months are excessively high when compared with CH (15%) or with preliminary results of IPOM at 8 months of follow-up (3%). Despite reduced perioperative pain and disability and promising preliminary results in the IPOM group, these intermediate follow-up data strongly suggest that the IPOM technique should not be used for repair of inguinal hernias.

Adhesion formation in laparoscopic inguinal hernia repair

BACKGROUND

In laparoscopic inguinal hernia repair controversy exists concerning the most appropriate repair method and implant material to use if intraabdominal adhesions are to be minimized.

METHODS

In 108 pigs, we implanted three different types of mesh by both the TAPP (transabdominal preperitoneal) and Onlay (prosthesis placed directly upon the peritoneum) methods. Specimens were harvested in three time periods and adhesion formation was compared.

RESULTS

Average adhesions at 3 days were TAPP 18% and Onlay 49% (p < 0.001). At 3 weeks average adhesions were TAPP 8% and Onlay 23% (p < 0.04). Three-month figures were TAPP 1% and Onlay 13% (p < 0.001). In contrast, there were no differences in adhesion formation due to material type in any of the three time periods (all p > 0.17).

CONCLUSIONS

A peritoneal covering over a laparoscopic inguinal implant significantly reduced adhesions. Prosthetic material type did not affect adhesion formation in this study.

Successful laparoscopic repair of paraesophageal hernia

OBJECTIVE

To evaluate prospectively the safety and efficacy of laparoscopic surgical techniques in the repair of types II and III paraesophageal hernias.

DESIGN

Case series.

SETTING

Tertiary-care, university-affiliated hospitals.

PATIENTS

Twelve consecutive patients undergoing elective laparoscopic repair of type II or type III paraesophageal hernias. Patients were available for follow-up for 1 to 17 months postoperatively.

INTERVENTIONS

All patients underwent laparoscopic paraesophageal hernia reduction and repair. Eight patients with gastroesophageal reflux disease underwent concurrent laparoscopic Nissen fundoplication.

MAIN OUTCOME MEASURES

Operative times, operative complications, and estimated blood loss were recorded. Postoperative outcome measurements included length of hospital stay, postoperative complications, postoperative gastrointestinal tract symptoms, and patient satisfaction.

RESULTS

All patients had successful completion of paraesophageal hernia repair laparoscopically with no recurrences, and with an overall minor morbidity rate of 25%, major morbidity rate of 8%, and no deaths. Eight of 12 patients with concomitant reflux disease underwent successful laparoscopic Nissen fundoplication with complete control of reflux symptoms. The average hospital stay for patients with uncomplicated courses was 2.5 days. Long-term (> 6 weeks) postfundoplication symptoms occurred in 13% of those patients who underwent fundoplication. Eleven (92%) of 12 patients described good to excellent results with complete or near complete control of all preoperative symptoms.

CONCLUSIONS

Laparoscopic repair of types II and III paraesophageal hernias can be performed under elective circumstances by experienced laparoscopic surgeons, with acceptable morbidity and comparable short-term efficacy. Addition of a concomitant antireflux procedure should be reserved for those patients with clear preoperative evidence of reflux disease secondary to a mechanically defective lower esophageal sphincter. Patients with a normal lower esophageal antireflux barrier do not need a concomitant antireflux procedure.

Preliminary results of a prospective randomized trial of laparoscopic onlay versus conventional inguinal herniorrhaphy

BACKGROUND

To compare laparoscopic onlay hernia repair with conventional surgery, 61 patients were randomized to either open or laparoscopic surgery.

METHODS

Traditional repairs were done according to the surgeons' preference. Laparoscopic repairs utilized a modified onlay technique with a meshed prototype prosthesis.

RESULTS

Mean operative time was 62.5 minutes for the laparoscopic group and 80.9 minutes for the open group. Each group had five complications. There were two conversions from laparoscopic to open surgery. Individuals undergoing laparoscopic surgery reported a mean intake of 5 doses of an oral narcotic analgesic versus 16 doses in the open group. Return to normal activity (nonstrenuous) was 7.5 days in the laparoscopic group and 18.5 days in the open group. After a mean follow-up of 8 months (range 1 to 14), there have been two recurrences in the open group and one in the laparoscopic group.

CONCLUSION

Laparoscopic onlay inguinal herniorrhaphy is a viable alternative for those who prefer a minimally invasive treatment for this disease.

Distribution of cytochrome oxidase in layers IV and V of the striate cortex in neonate monkeys

The uniformly dense staining for cytochrome oxidase (CO) in layer IV of area 17 in adult monkeys has been described as developing from a bilaminar pattern in neonates being composed of a broad CO band in layer IV alpha and a narrow CO band attributed to the innermost zone of layer IV beta. Here we present evidence, in the neonate marmoset monkey, for the narrow CO band to be localized in the outermost rim of layer V, designated as sublayer Va.

Delineation of the striate cortex, and the striate-peristriate projections in the guinea pig

The size and position of the guinea pig area 17 were determined by transneuronal labeling after intraocular injections of 3H-proline or WGA-HRP. Area 17 occupies a large region of the occipital cortex located between two shallow fissures, the fissura sagittalis lateralis and the lateral groove. Area 17 extends for about 6 mm rostral from the occipital pole of the hemisphere, and encroaches occipitally for more than 1 mm upon the ventromedial surface of the hemisphere; the lateral width is up to 4.5 mm. Single injections of WGA-HRP into area 17 produced eight patches of transported tracer which formed the same general pattern in the peristriate cortex, regardless of the position of the injection within the visual field representation of area 17. Two of these patches were found in anteromedial peristriate cortex; three patches were distributed anterolateral and lateral of area 17; and three patches were located in posterolateral peristriate cortex. For several reasons, each of these patches was interpreted as representing a single striate projection onto a separate peristriate area. Comparison of these results with published findings indicates that the parcellation of the peristriate cortex into a variety of different areas, the pattern formed by these areas around area 17, and their reciprocal connections with area 17 follow a common plan in all hitherto studied terrestrial Old World and New World rodents. Lucifer Yellow injections into striate cells projecting to one of the recipient areas (AM) indicated that the pyramidal cells of this set of striate neurons are characterized by a short apical dendrite, and that the basal dendrites of the layer V pyramidal cells branch more profusely than those of the layer III pyramids.

Parvalbumin in rat superior colliculus

Parvalbumin-like immunoreactivity (PA-LI) has been studied in sections of the superior colliculus (SC) of the rat and its distribution compared to the patterns of acetylcholinesterase (AChE) and cytochrome oxidase (CO) staining. In the intermediate layers it was found that PA-LI is spatially associated with AChE only in the medial part of the SC, but assumes a complementary distribution further laterally. There was a positive correlation between PA-LI and CO. We conclude that the patterns of PA-LI and CO are not systematically related to collicular input known to be associated with the AChE-rich zones, but may reflect adherence to channel separation beyond the terminal fields of clustered afferents.