Technical Strategies for Harvest of the Subtotal Pedicled Fillet of Thigh Flap for Reconstruction of External Hemipelvectomy and Hemicorporectomy Defects.

External hemipelvectomy and hemicorporectomy have been described in the literature for a variety of indications. A commonly used reconstructive technique is the pedicled anterior subtotal fillet of thigh flap. However, there are few descriptions regarding the technical pearls of harvest and inset of this flap. Here, we describe our step-by-step technique, as performed in three patients. The flap is pedicled on the common femoral artery and extends longitudinally to the knee to achieve the length required to extend past the midline and resurface sacral pressure ulcers, which are commonly found in patients who undergo this procedure for refractory pelvic osteomyelitis. Additionally, we describe a potential salvage option with late division of the popliteal artery to preserve the option for free tissue transfer of a subtotal fillet of lower leg flap.

Thermal Conductivity of Human Bone in Cryoprobe Freezing as Related to Density.

Cryoprobes create localized cell destruction through freezing. Bone is resistant to temperature flow but is susceptible to freezing necrosis at warmer temperatures than tumor cells. Few studies have determined the thermal conductivity of human bone. No studies have examined conductivity as related to density. The study goal was to examine thermal conductivity in human bone while comparing differences between cancellous and cortical bone. An additional goal was to establish a relationship between bone density and thermal conductivity. Six knee joints from 5 cadavers were obtained. The epiphyseal region was sliced in half coronally prior to inserting an argon-circulating cryoprobe directed away from the joint line. Thermistor thermometers were placed perpendicularly at measured increments, and the freezing cycle was recorded until steady-state conditions were achieved. For 2 cortical samples, the probe was placed intramedullary in metaphyseal samples and measurements were performed radially from the central axis of each sample. Conductivity was calculated using Fournier's Law and then plotted against measured density of each sample. Across samples, density of cancellous bone ranged from 0.86 to 1.38 g/mL and average thermal conductivity ranged between 0.404 and 0.55 W/mK. Comparatively, cortical bone had a density of 1.70 to 1.86 g/mL and thermal conductivity of 0.0742 to 0.109 W/mK. A strong 2-degree polynomial correlation was seen (R2=0.8226, P<.001). Bone is highly resistant to temperature flow. This resistance varies and inversely correlates strongly with density. This information is clinically relevant to maximize tumor ablation while minimizing morbidity through unnecessary bone loss and damage to surrounding structures. [Orthopedics. 2017; 40(2):90-94.].

Myxoid Liposarcoma of the Thigh with Metastasis to the Left Ventricle of the Heart: A Case Report.

CASE: This report describes a sixty-one-year old man who was diagnosed with a myxoid liposarcoma of the left thigh that was resected and then treated with radiation therapy. He underwent yearly surveillance imaging but presented seventeen years after initial resection with symptoms of heart failure. He was found to have a cardiac abnormality that was first thought to be a pseudoaneurysm but was later shown to be a myxoid liposarcoma, presumably metastatic. CONCLUSION: Myxoid liposarcoma can present with late metastasis, including to the heart.

Skin temperatures generated following plaster splint application.

Heat is generated during the exothermic reaction associated with plaster splint application. The amount of heat generated is affected by the plaster thickness, dipping water temperature, and extremity elevation method. The authors assessed the effect of these variables on skin and plaster temperatures. Short-leg posterior splints were applied to noninjured extremities on a volunteer using 2 protocols. Following splint application, the splinted leg was elevated in 4 ways: on plastic-covered urethane pillows in cotton pillowcases, on cotton blankets, on ice packs (short-term cryotherapy) placed on top of cotton blankets, or with heel elevation to promote free air circulation. Skin and plaster temperatures were monitored at 1-minute intervals. The maximum skin temperature generated and the average time that skin temperature was 40 °C or higher were recorded.

Surgical strategies to achieve a custom-fit TKA with standard implant technique.

Recent trends in implant design have been geared toward taking individual differences in knee anatomy into consideration and modifying implants to accommodate these distinctions. The unique anatomy of the female knee gave birth to sex-specific knee implants and began a new era in implant design. This opened the door for the next progression of patient-specific cutting guides and implants. The current trend in implant design addresses individual variation with 3-D modeling that necessitates preoperative magnetic resonance imaging or computed tomography scans. While these innovations may turn out to be worthwhile, their use is currently limited by their expense and debatable clinical significance. Surgeons should not forget the basic surgical strategies to tailor their surgery to customize the fit of the standard implant. The surgical pearls reviewed here will allow surgeons to better understand sizing and customize every total knee arthroplasty with a patient-specific surgery. [corrected]