John Davis

Minimally invasive total knee replacement through a mini-midvastus incision : an outcome study

Total knee replacement traditionally has been done through an anterior incision approximately 18 cm long, using a capsular incision that separates the interval between the rectus femoris and vastus medialis musculature. Although giving excellent exposure, this incision also disrupts the suprapatellar pouch and may lead to adhesions and difficulty with rapidly regaining flexion. It is hypothesized that, by using a more minimally invasive incision, there will be a more rapid return of flexion and the patient will require fewer narcotic medications postoperatively. This retrospective review compared 32 total knee replacements done through a minimally invasive mini-midvastus approach with 26 total knee replacements done through the standard medial parapatellar approach. Preoperative Knee Society scores and postoperative functional outcomes were compared. Postoperative flexion was measured daily during hospitalization and at a 6-week and 3-month followup. Pain was assessed by a visual analog scale and the amount of pain medication used during hospitalization. Implant position was measured. The MIS group had an average skin incision length of 12.8 cm. Passive flexion on a daily basis was significantly higher in the MIS group compared with the standard group. At 6 weeks postoperatively, the change in Knee Score was statistically higher in the MIS group and the average visual analog pain score and the total amount of pain medication was lower. The radiographic alignment and position of all the components was normal in all patients in both groups. The limited disruption of the extensor mechanism results in more rapid restoration of the quadriceps muscle control.

Pediatric orbital fractures: classification, management, and early follow-up.

Background: Scarce literature exists addressing the presentation, classification, and management of pediatric orbital fractures. The aim of this study is to review the authors experience with the presentation, management, and early follow-up of pediatric orbital fractures. Methods: A retrospective review of pediatric orbital fractures presenting to the Childrens Hospital of Pittsburgh between 2003 and 2007 was performed. Demographics, associated injuries, computed tomographic scan findings, management, and follow-up were collected. From these data, a pediatric orbital fracture classification system was devised. Results: Seventy-four patients (81 orbits) were reviewed. Average age at presentation was 8.6 years. Fractures were distributed as follows: type 1, 40.7 percent; type 2, 33 percent; and type 3, 25.9 percent. Twenty-three orbits were treated surgically and 58 were treated nonoperatively. The operative rates were as follows: type 1, 9.1 percent; type 2, 14.8 percent; and type 3, 76.2 percent. Complications included minor enophthalmos in seven patients, and persistent cerebrospinal fluid leak in two growing skull fractures. For type 1 (pure orbital) fractures, three (12 percent) underwent surgical treatment for acute enophthalmos, vertical orbital dystopia, or muscle entrapment. Twenty-two orbits (88 percent) were managed nonoperatively. At an average follow-up of 13 months, minimal enophthalmos (1 to 2 mm) was found in one of the surgically treated fractures (33 percent) and in three of the conservatively managed fractures (13.6 percent). Conclusions: For type 1 (pure orbital) fractures, unless there is evidence of acute enophthalmos, vertical orbital dystopia, or muscle entrapment, a nonoperative approach is advocated. Type 2 (craniofacial) fractures should be followed with serial computed tomographic scans; and type 3 (common fracture patterns) fractures have a greater chance of requiring surgery.

The Aquamantys System—An Alternative To Reduce Blood Loss in Primary Total Hip Arthroplasty?

To evaluate the effectiveness of the Bipolar Sealer 6.0-VT (BPS 6.0-VT) (Tissue Link Medical, Inc, Dover, NH) in reducing blood loss compared with a conventional electrocautery (Erbe ICC 350) (Erbe ICC 350 (ERBE Elektromedizin GmbH, Tübingen, Germany). A prospective randomized trial of 105 patients with primary total hip arthroplasty (Erbe ICC 350: 50 patients; BPS 6.0-VT: 55 patients). On the basis of the calculation of the preoperative blood volume the total and postoperative blood loss were calculated. No statistically significant difference could be shown for total intraoperative and postoperative blood loss (group A 1846 mL; group B 1740 mL) (t test). Due to the lack of reduction of blood loss and the high costs of the BPS 6.0-VT, its use is not recommended in primary total hip arthroplasty.

Ischemia-Reperfusion Injury in Myocutaneous Flaps: Role of Leukocytes and Leukotrienes

&NA; Leukotriene B4 is a potent inflammatory mediator that is derived from the 5‐lipoxygenase pathway of arachidonic acid metabolism and that has been implicated in the pathophysiology of polymorphonuclear leukocyte‐dependent reperfusion injury in a variety of organ systems. The objectives of these investigations were to determine whether inhibition of leukotriene B4 attenuates postischemic polymorphonuclear leukocyte infiltration and subsequent injury in myocutaneous flaps. Anesthetized female Yorkshire pigs were randomized to receive normal saline (n = 8), the 5‐lipoxygenase inhibitor diethylcarbamazine (n = 7), or the leukotriene B4 receptor antagonist SC‐41930 (n = 7). All animals underwent 6 hours of rectus abdominis myocutaneous flap ischemia followed by 4 hours of reperfusion. In saline‐treated controls, flap ischemia was associated with massive polymorphonuclear leukocyte infiltration at 1 and 4 hours of reperfusion (252 ± 70 and 619 ± 137 polymorphonuclear leukocytes per 25 high‐power fields, respectively). Skeletal muscle neutrophil content was significantly attenuated by pretreatment with diethylcarbamazine (72 ± 29 and 229 ± 63 polymorphonuclear leukocytes per 25 high‐power fields; p < 0.05) or SC‐41930 (25 ± 3 and 193 ± 25 polymorphonuclear leukocytes per 25 high‐power fields; p < 0.05). Wet‐to‐dry weight ratios of full‐thickness flap biopsies were lower in the diethylcarbamazine and SC‐41930 groups (2.98 ± 0.15 and 2.90 ± 0.26, respectively) than in the control group (4.13 ± 0.23; p < 0.01), and mean muscle infarct size, as determined by nitroblue tetrazolium staining, diminished from 47.6 ± 11.3 percent in controls to 25.1 ± 6.5 percent in diethylcarbamazine‐treated animals and 7.3 ± 4.8 percent in SC41930‐treated animals (p < 0.05). These data indicate that leukotriene B4 plays a critical role in mediating neutrophil‐dependent injury in postischemic skeletal muscle flaps.

Nosocomial infections and nosocomial pneumonia

Nosocomial infections are a major source of revenue loss, morbidity, and even mortality to surgical patients. This review presents current issues regarding nosocomial infections and nosocomial pneumonias. This study is a literature review that presents material on nosocomial infections in general and details regarding Clostridium difficile and vancomycin-resistant enterococcus infections. Nosocomial infections, including pneumonias, are serious medical complications, and prevention by strict adherence to barrier precaution is the most important means of protecting the patient from hospital-acquired bacterial flora.

Surgical infection society position on vancomycin-resistant enterococcus

The risk of transfer of vancomycin resistance to staphylococci is a real possibility and has been achieved in the laboratory. Prolonged colonization occurs with vancomycin-resistant Enterococcus (VRE), and many more patients are colonized than infected. The failure to identify, isolate, and adhere to infection control measures when caring for VRE-colonized patients dooms to failure any means to control its spread. Control of vancomycin use alone is unlikely to greatly affect the number of patients at risk for VRE colonization. The global spread of VRE may be impossible to stop, but infection control measures are the most important line of defense inside hospitals.

Leukotriene Generation and Pulmonary Dysfunction following Aortic Cross Clamp in Humans

Respiratory distress seen after reprefusion of ischemic extremities is thought to be mediated by neutrophils (PMN) and has been well studied in animals-5 and in humans undergoing aortic bypass s ~ r g e r y . ~ The following study was performed to determine whether PMN production of LTB4 increases and is clinically significant following aortic occlusion in humans during elective abdominal aortic aneurysm repair.

Can Planned Traffic Patterns Improve Survival Among the Injured During Mass Casualty Motorcycle Rallies

BACKGROUNDnMass casualty events are infrequent and create an abrupt surge of patients requiring emergency medical services within a brief period. We hypothesize that implementation of a controlled traffic loop pattern during a planned high-volume motorcycle rally could improve overall mortality and impact patient outcomes.nnnMATERIALS AND METHODSnWe performed a retrospective analysis of all motorcycle-related injuries during the citys annual motorcycle rally over a 4-y period. Comparative analysis was completed between those injured during nontraffic loop hours versus the citys scheduled 23-mile, 3-d traffic loop pattern. The two groups were compared for age, gender, injuries, Injury Severity Score, Glasgow Coma Scale, length of stay, ventilator-free days, and mortality. The primary outcome was mortality.nnnRESULTSnA total of 139 patients were included (120 nonloop and 19 loop). Mean (standard deviation) age was 36.1 (11.2) y and 72.1% were male. Both groups were equivalent in age, gender, Injury Severity Score, and Glasgow Coma Scale. Traffic loop patients required longer intensive care unit length of stay, (medianxa0=xa09.0, range: 1-49xa0d), ventilator days (medianxa0=xa029.5), (range: 1-49xa0d) and experienced abdominal trauma (Pxa0=xa00.002). Emergency medical services transport times during loop hours had shorter response times than the nonloop injury group (7.79xa0±xa05.2xa0min and 13.22xa0±xa014.01xa0min (Pxa0=xa00.049). No deaths occurred during the citys scheduled traffic loop (0 versus 22, Pxa0=xa00.0447).nnnCONCLUSIONSnControlled traffic patterns during high-volume city gatherings can improve overall mortality and morbidity. Regional trauma system preparedness with field triage guidelines and coordinated trauma care is warranted to effectively care for the injured.