Preservation Of Length Research Articles

Area, length and thickness conservation: Dogma or reality?

The basic assumption of quantitative structural geology is the preservation of material during deformation. However the hypothesis of volume conservation alone does not help to predict past or future geometries and so this assumption is usually translated into bed length in 2D (or area in 3D) and thickness conservation. When subsurface data are missing, geologists may extrapolate surface data to depth using the kink-band approach. These extrapolations, preserving both thicknesses and dips, lead to geometries which are restorable but often erroneous, due to both disharmonic deformation and internal deformation of layers. First, the Bolivian Sub-Andean Zone case is presented to highlight the evolution of the concepts on which balancing is based, and the important role played by a decoupling level in enhancing disharmony. Second, analogue models are analyzed to test the validity of the balancing techniques. Chamberlin's excess area approach is shown to be on average valid. However, neither the length nor the thicknesses are preserved. We propose that in real cases, the length preservation hypothesis during shortening could also be a wrong assumption. If the data are good enough to image the decollement level, the Chamberlin excess area method could be used to compute the bed length changes.

Moberg Modification using the First Web Space: Thumb Reconstruction Following Distal Amputation

The Moberg neurovascular advancement flap, first described in 1964, has proven to be ideal for soft tissue defects of the thumb pulp measuring ≤1.5 cm in size [8]. For such small defects, this technique provides sufficient skin coverage allowing preservation of length and most importantly good restoration of sensation and function [2, 5]. Modifications to the Moberg flap have allowed coverage of deficits >1.5 cm but have been hampered by the residual defect located at the donor site. In 1968, O’Brien proposed the use of a split thickness skin graft to cover the donor deficit [9]. The disadvantages of a skin graft such as immobilization, risk of graft failure, and contracture render this technique less attractive. Others have avoided grafting with V–Y modifications to the Moberg flap [1, 3, 4, 10]. However, tension at the donor site often occurs and may result in incomplete closure or in skin necrosis. In these instances, splinting in the flexed position to decrease tension or dressing changes to encourage epithelialization when complete primary closure is not feasible is required [4, 7]. As a consequence, scar hypertrophy, contractures, joint stiffness, and delayed mobilization may prolong return to function. Dellon demonstrated that defects of up to 3 cm could be resurfaced using an extended palmar flap with dissection into the thenar eminence [3]. Two rotational flaps are used to close the donor deficit. Although providing good closure, this technique requires extensive dissection and is technically difficult. We present a new modification of the Moberg–O’Brien technique that utilizes the skin of the first web space to fill the proximal defect caused by the mobilization of the flap. This simple technique provides tension-free closure and avoids the need for immobilization or dressing changes. Excellent esthetics and function is achieved by deepening the first web space with a Z-plasty and hence increasing the relative length of the thumb. Operative Technique After drawing the incisions, we proceed with the elevation of the Moberg flap along a single plane superficial to the flexor pollicus longus tendon sheath (Fig. 1). A transverse incision at the base of the thumb metacarpophalangeal (MCP) joint is made in order to elevate the flap on its neurovascular bundles. Hence the incision is made on the volar side of the MCP; care is taken to leave the base of the transposition flap intact (located at the base of the thumb on the dorso–ulnar side). Once the flap is advanced and fixed with 4-0 nylon, the proximal deficit is covered using the transposition flap of the first web space (Fig. 2) with a 3:1 ratio and removal of the triangular point for a final rectangular shape. This transposition flap is raised in a plane superficial to the first dorsal interosseous and thumb adductor muscles. It is rotated 150° to cover the proximal deficit and is sutured loosely with 4-0 nylon in a manner as to not compromise the neurovascular pedicle of the Moberg flap (Fig. 2). In order to deepen the first web space and to prevent the formation of scar contracture, a Z-plasty is then performed in the first web space (Fig. 3). A loose dressing is positioned without immobilization. Patients were satisfied with esthetic and functional outcomes (interview and at follow-up visit). For the purpose of this paper, we present the readers with three cases. Open in a separate window Fig. 1 Case 1—operative technique: Moberg–O’Brien flap. Two mid-axial incisions dorsal to the neurovascular bundle and one transverse incision at the base of the first metacarpal are drawn according to the Moberg–O’Brien flap. The transverse incision must not cross the base of the transposition flap, which is based on the dorso–ulnar aspect of the side of the thumb and extending across the first web space. The tracings for the Z-plasty of the first web space are completed. The flap is elevated along a single plane superficial to the flexor pollicis longus tendon sheath

Island Volar Advancement Flap for Reconstruction of Thumb Defects

The volar advancement flap of the thumb described by Moberg has been used for pulp defects up to 1 to 1.5 cm since its mobility is quite limited due to the stiff nature and fibrous connections of the regional skin with underlying structures. There have been several attempts to increase the mobility of this useful flap by adding V-Y and Z-plasty concepts into the technique. These modifications could provide a slight increase in the flap advancement and achieve closure of defects up to 2 cm in length at best. In this study, we describe the island volar advancement flap of the thumb in which all attachments, except the neurovascular pedicle of the flap, were divided to provide maximum mobility and advancement. This technique was used in 12 patients for reconstruction of traumatic defects of the distal thumb up to 3 to 3.5 cm in length. The flaps healed uneventfully in all patients. There was no patient with flap failure. All patients were followed up for 2 to 6 years (4 years on an average). Our results revealed sensible and durable skin coverage with maximum preservation of the thumb length. The island volar advancement flap seems to be a safe and useful procedure for thumb reconstruction. Providing a 1.5 cm of extra flap advancement, this new procedure enables us 1-stage closure of considerably large defects and is a critical achievement in thumb reconstruction.

Long‐term outcomes of epiphyseal preservation and reconstruction with inactivated bone for distal femoral osteosarcoma of children

To study the long-term outcomes of inactivated bone reimplantation with preservation of the epiphysis in children with distal femoral osteosarcomas. Over 10 years, five children (mean age 9.2 years, one boy and four girls) with distal femoral osteosarcomas underwent inactivated bone reimplantation with preservation of the epiphysis following chemotherapy in our hospital. Three patients were type I on MRI classification (one with pathological fracture), and two type II. The therapeutic regime was two cycles of preoperative chemotherapy, surgery and six cycles of postoperative chemotherapy. Five patients were followed up for 60-126 months (mean 82 months). No local tumor recurrences or metastases occurred. Three patients with fractures of inactivated bone were treated by open reduction, bone grafting and internal fixation; their fractures had united by 6 months after reoperation. The mean functional score of the affected limbs was 25.6 points (13-30 points). Inactivated bone reimplantation with preservation of the epiphysis for distal femoral osteosarcomas in children optimizes recovery of limb function and preservation of limb length. The main measures for improving clinical outcomes include preoperative analysis of the lesion's boundaries and extent of tumor invasion, bone grafting between inactivated and host bone, and timely treatment of complications.

COMBINATION V-Y ADVANCEMENT FLAP AND COMPOSITE GRAFT FOR RECONSTRUCTION OF AN AMPUTATED FINGERTIP

Fingertip amputations can lead to both functional and aesthetic problems. We present the results of our preferred technique to address fingertip amputations in zone 1 and zone 2 which have been deemed non-replantable by microsurgery. It is based on the "reposition technique" described by Dubert et al. in 1997(1) and the free perionychial graft technique suggested by Netscher and Meade in 1999.(2) The technique that we prefer is best described as a combination of an advancement flap and a composite graft. So far seven patients have been treated with this method and our results have been satisfactory in all of them. It is a simple and quick technique that does not require advanced skills and can be done by a well-trained resident or fellow. It allows preservation of finger length, retains the nail and is functionally and aesthetically pleasing.

Dietary supplementation of krill oil attenuates inflammation and oxidative stress in experimental ulcerative colitis in rats

Objective. To evaluate the effects of krill oil (KO) on inflammation and redox status in dextran sulfate sodium (DSS)-induced colitis in rats. Materials and methods. Thirty male Wistar rats were divided into three groups: Control, DSS, and DSS + KO 5% in a 4-week diet study. Colitis was induced by 5% DSS in the drinking water the last week of the experiment. Weight and disease activity index (DAI), colon length, histological combined score (HCS), colon levels of selected cytokines and prostaglandins, markers of protein oxidative damage, fatty acid profile, and expression of selected genes were measured. Results. Rats in the DSS group increased their DAI and HCS compared with healthy controls. The colon length was significantly preserved after KO diet. Tumor necrosis factor (TNF)-α and interleukin (IL)-1β were elevated in the DSS group compared with controls. Cytokines and HCS were nonsignificantly lower in the KO versus the DSS group. Prostaglandin (PG)E3 increased significantly in the KO versus the other groups. Peroxisome proliferator-activated receptor (PPAR)-γ expression was nonsignificantly increased while PPAR-γ coactivator 1α (Pparg1α) expression increased significantly after KO. The levels of protein oxidation markers decreased significantly. Conclusions. KO showed protective potential against DSS colitis based on the preservation of colon length, reduction of oxidative markers and the consistent beneficial changes of HCS, cytokine, and (PG)E3 levels, as well as PPAR-γ and Pparg1α expression compared with DSS alone. These findings indicate an anti-inflammatory and a protein antioxidant effect of KO.

A Quasi-Dynamic Robust Control Scheme for Signalized Intersections

Conventional vehicle-actuated traffic signal control attempts to achieve system optimum by ending a phase as soon as queues served during that phase vanish. In this article, the authors extend this logic to intersections where a stable cycle length is desirable (e.g., for signal coordination or other considerations). The proposed control scheme dynamically updates green allocation to keep queues on all approaches well balanced. Different from fully dynamic control strategies, the proposed quasi-dynamic scheme is based on a finite set of fixed timing plans with a common cycle length. The decision of switching from one plan to another is made at the beginning of each cycle based on the queue state in the previous cycle. Our experimental results showed that the performance of the proposed scheme is robust with respect to random fluctuation, systematic changes in demand, and input data quality. Although the proposed scheme does not attempt to minimize total system delay directly, it provides a good solution for reducing total system delay compared with the signal timing plan optimized for system delay. The preservation of a stable cycle length in the proposed signal timing plan has made it possible to incorporate the proposed scheme into the development of control strategies for an arterial where signal coordination is essential to the performance of the system.

Minimally Invasive Reconstructive Surgery for Complex Oncologic Foot Defects in Children

Sir: Recently Iorio et al.1 and previously Lee et al.2 evaluated the clinical results of the lower extremity reconstruction by using Integra, a bioengineered dermal matrix, in diabetic patients and burn injury, respectively. Iorio reviewed the use in 121 wounds and concluded that Integra is a viable option for reconstruction in diabetic patient at low risk for amputation.1 Analyzing nine complex burn injuries, Lee et al. observed Integra to be a stable wound coverage that should be considered as part of the lower extremity wound coverage algorithm.2 These authors' experience in the therapeutic challenge for the preservation of functional limb length showed that Integra provides durable coverage of vital lower extremity structures. We believe this is also a key reconstructive option in pediatric oncology patients, in which this matrix allows salvage of extremities that might be amputated or require prolonged staged procedures. We would like to report our experience with a plantar rhabdomyosarcoma in a child in which the use of Integra has allowed us to improve young patient care, with a minimally invasive reconstruction after extensive demolition in the same operative session.3 A left plantar massive neoplasm (10 × 3.7 cm) involving the flexor digitorum brevis was determined by biopsy to be alveolar rhabdomyosarcoma. Surgical resection of the tumor with total exeresis of the flexor digitorum brevis, plantar aponeurosis, and skin by en bloc radical soft-tissue excision was performed, with exposition of the flexor hallucis longus tendon, the flexor digitorum longus tendons, and the quadratus plantar muscle (Fig. 1). The wide and deep defect was reconstructed by using a single layer of Integra measuring 12.5 × 10 cm that we folded to obtain a width of 5 cm and greater thickness. By using Integra, we protect the exposed muscle-tendon structures and provide immediate wound closure, and the heel was reconstructed by suture plans. Sixteen days postoperatively, Integra was biodegraded and in its place was neodermis with full restoration of the thickness and complete preservation of the exposed structures (Fig. 2). Skin grafting restored epidermal coverage after definitive histologic assessment determined it to be tumor-free. The morphologic functional recovery of the salvaged limb was complete, with restoration of the internal longitudinal arch and normal plantar and finger flexion. At 36-month follow-up, the patient had no evidence of disease; he had regained satisfactory function and reported good quality of life, no functional limitations, and normal walking and gait. (See Video, Supplemental Digital Content 1, which demonstrates that walking is unhindered and gait is normal, https://links.lww.com/PRS/A367.)Fig. 1.: En bloc radical soft-tissue excision of 12.5 × 5 × 3 cm and exposition of the flexor hallucis longus tendon, the flexor digitorum longus tendons, and the quadratus plantar muscle (structures responsible for plantar and finger flexion).Fig. 2.: Neodermis induced by Integra.Video.: Supplemental Digital Content 1 demonstrates that walking is unhindered and gait is normal, https://links.lww.com/PRS/A367.Rhabdomyosarcoma is a highly malignant tumor and the most common soft-tissue sarcoma in children. Localization in the foot is rare. The unique anatomy of the foot presents challenges in reconstructing a viable and functional limb.4 Reconstructive surgery in children with cancer is complex and often requires multiple procedures. Free flap surgery is the most common reconstruction5 and usually results in excellent outcomes. Drawbacks are longer operative time, invasiveness and complexity of the procedure, large skin incisions, donor-site morbidity, possible flap loss or necrosis of the distal portion with delayed healing, cosmetic problems, and patient intolerance. An exclusion criterion can be situations of specific risk, such as very aggressive histologic subtypes (i.e., alveolar), where the final reconstruction should be deferred pending definitive histologic assessment. Reconstruction using Integra has allowed us to override the above-mentioned drawbacks with complete recovery. Thus, Integra following resection of a malignant plantar tumor has proven to be a successful technique, offering an important alternative to the traditional reconstructive choices. The technique is easy and minimally invasive, with operative time reduced. It avoids major complications and wide donor-site scarring. It is ideal for immediate wound closure pending final histologic assessment, simplifying wound care and improving patient tolerance, with good healing and rapid recovery. DISCLOSURE The authors have no financial interests to declare in relation to the content of this communication. No outside funding was received. Maria Giuseppina Onesti, M.D. Maria Ida Rizzo, M.D. Anna Maria Spagnoli, M.D. Nicolò Scuderi, M.D. Department of Plastic Surgery La Sapienza University of Rome Rome, Italy

Traction Therapy for Men with Shortened Penis Prior to Penile Prosthesis Implantation: A Pilot Study

Loss of penile length after penile prosthesis implantation is one of the most common complaints. There is no recognized reliable technique to gain length once the device is placed. This noncontrolled pilot study was designed to evaluate the efficacy and safety of external penile traction therapy in men with a shortened penis used before inflatable prosthesis implantation. Ten men with drug refractory erectile dysfunction and a complaint of a shorter penis as a result of radical prostatectomy in four, prior prosthesis explantation in four, and Peyronie's disease in two were entered into this trial. External penile traction was applied for 2-4 hours daily for 2-4 months prior to prosthesis surgery. Baseline stretched penile length (SPL) was compared with post-traction SPL and postimplant inflated erect length. A non-validated questionnaire assessed patient satisfaction. All men completed the protocol. Daily average device use was 2-4 hours and for up to 4 months. No man had measured or perceived length loss after inflatable penile prosthesis placement. Seventy percent had measured erect length gain compared with baseline pre-traction SPL up to 1.5 cm. There were no adverse events. External traction therapy appears to result in a preservation of penile length, as no man had measured or perceived length loss following prosthesis placement, but in fact, a small length gain was noted in 70% of the subjects with no adverse events. The protocol is tedious and requires compliance to be effective. External traction therapy prior to inflatable penile prosthesis placement appears to preserve and possibly result in increased post-prosthesis implant erect length.

Skeletal Anchorage for Orthopedic Correction of Growing Class III Patients

Maxillary protraction headgear in conjunction with expansion appliances have been widely used in the treatment of Class III malocclusion with maxillary deficiency. However, there are problems associated with protracting the maxilla with conventional tooth-borne anchorage. These include the loss of dental anchorage, which is of concern, especially in situations in which preservation of arch length is necessary. In addition, tooth borne anchorage alone does not allow the application of orthopedic force directly to the maxillary sutures. The latter effects can be eliminated or minimized by the use of absolute intraoral anchorage devices, such as miniplates. Several reports have been published in the literature on the use of miniplates for maxillary protraction. However, the skeletal and dental changes in response to maxillary protraction using miniplates as anchorage have not been reported. The purpose of the present study was to quantify and compare the effects of maxillary protraction when using a facemask in conjunction with a rapid maxillary expansion appliance (RME) with a second group treated with a facemask together with a surgical miniplate as anchorage. Maxillary protraction headgear in conjunction with expansion appliances have been widely used in the treatment of Class III malocclusion with maxillary deficiency. However, there are problems associated with protracting the maxilla with conventional tooth-borne anchorage. These include the loss of dental anchorage, which is of concern, especially in situations in which preservation of arch length is necessary. In addition, tooth borne anchorage alone does not allow the application of orthopedic force directly to the maxillary sutures. The latter effects can be eliminated or minimized by the use of absolute intraoral anchorage devices, such as miniplates. Several reports have been published in the literature on the use of miniplates for maxillary protraction. However, the skeletal and dental changes in response to maxillary protraction using miniplates as anchorage have not been reported. The purpose of the present study was to quantify and compare the effects of maxillary protraction when using a facemask in conjunction with a rapid maxillary expansion appliance (RME) with a second group treated with a facemask together with a surgical miniplate as anchorage.

Short-Term Effects of Muscular Denervation and Fasciotomy on Global Limb Variables during Locomotion in the Decerebrate Cat

The motor system is capable of preserving the trajectories during locomotion of task level variables such as limb length and limb orientation in the face of paralysis of major muscle groups. This compensation is accomplished by the adjustment of the kinematics of joints other than the one most affected by the paralysis. The conservation of these task level variables could be accomplished quickly by feedback regulation or intrinsic mechanics, or by a longer-term adaptive process. We investigated the immediate effects of denervation of the triceps surae muscles in one limb of stepping, decerebrate cats to determine whether task level variables were preserved by short-term regulatory or intrinsic mechanisms. We further investigated the effects of disruption of the crural fascia in conjunction with denervation of the triceps surae muscles to determine whether the system consisting of multi-articular muscles of the thigh and crural fascia provided some contribution toward the preservation of limb length and orientation. Denervation led to substantial increases in ankle yield during stance, as previously observed, but also to significant decreases in limb length during early stance. Disruption of the crural fascia did not lead to increased ankle yield but, instead, to evidence for decreased propulsion. The results suggest that the preservation of task level variables observed in other studies does not result from online error correction or intrinsic properties of the musculoskeletal system but, by inference, from longer-term neural adaptation.

Functional Limb Salvage in the Diabetic Patient: The Use of a Collagen Bilayer Matrix and Risk Factors for Amputation

The diabetic foot ulcer presents a therapeutic challenge with a high rate of limb infection and extremity amputation. Adequate debridement and stable coverage of exposed structures are paramount to preserving limb length. The authors reviewed their use of a collagen bilayer matrix in the diabetic population for the preservation of functional limb length. Salvage rates were stratified with patient comorbidities of severe peripheral arterial disease and/or persistent infection. A retrospective review was performed of all consecutive patients who underwent application of Integra by the senior authors (J.S.S., C.E.A.) for lower extremity salvage between January of 2004 and December of 2008. A total of 105 patients with 121 separate wounds were analyzed. Patient age ranged from 22 to 80 years (mean, 58 years). The average wound size was 25.9 cm2 in the diabetic population. Average follow-up was 325 days, and average number of operations before closure was 1.28. In the diabetic population, of the 59 patients identified as low risk for amputation, 10 (17 percent) progressed to amputation. Of the 28 patients identified as high risk for amputation, 15 (54 percent) progressed to amputation. In the nondiabetics, 31 patients were classified as low risk for amputation, and one (3 percent) went on to an amputation. Use of a collagen bilayer matrix appears to be a viable option for reconstruction and stable closure in the diabetic patient at low risk for amputation, with risk based on available blood supply and evidence of infection. In the diabetic patient at high risk for amputation, however, the rate of salvage may not be improved with the use of Integra.

Long-Term Infection Outcomes After Original Antibiotic Impregnated Inflatable Penile Prosthesis Implants: Up to 7.7 Years of Followup

Although some studies suggest that most infections associated with inflatable penile prosthesis implantation develop within year 1 after surgery, device related infections have been reported 5 years after implantation or later and the infection risk with time is not well characterized. We previously reported a statistically significantly lower infection rate for original inflatable penile prostheses impregnated with antibiotic treatment with minocycline and rifampin vs nonimpregnated inflatable penile prostheses at 1-year followup. Long-term data are now available on infection revision after initial implantation of antibiotic impregnated vs nonimpregnated prostheses. We retrospectively reviewed patient information forms voluntarily filed with the manufacturer after the initial implantation of more than 39,000 inflatable penile prostheses to compare the revision rate due to infection for antibiotic impregnated vs nonimpregnated implants between May 1, 2001 and December 31, 2008. Life table analysis was used to evaluate device survival from revision surgery. On life table survival analysis initial revision events due to infection were significantly less common in the impregnated vs the nonimpregnated group (log rank p <0.0001). At up to 7.7 years of followup 1.1% of 35,737 vs 2.5% of 3,268 men with impregnated vs nonimpregnated implants underwent initial revision due to infection. To our knowledge this long-term outcome analysis provides the first substantial clinical evidence of a decrease in costly infection related revision using an antibiotic impregnated inflatable penile prosthesis.

Traumatic and Trauma-Related Amputations

Deliberate attention to the management of soft tissue is imperative when performing an amputation. Identification and proper management of the nerves accompanied by the performance of a stable myodesis and ensuring robust soft-tissue coverage are measures that will improve patient outcomes. Limb length should be preserved when practicable; however, length preservation at the expense of creating a nonhealing or painful residual limb with poor soft-tissue coverage is contraindicated. While a large proportion of individuals with a trauma-related amputation remain severely disabled, a chronically painful residual limb is not inevitable and late revision amputations to improve soft-tissue coverage, stabilize the soft tissues (revision myodesis), or remove symptomatic neuromas can dramatically improve patient outcomes. Psychosocial issues may dramatically affect the outcomes after trauma-related amputations. A multidisciplinary team should be consulted or created to address the multiple complex physical, mental, and psychosocial issues facing patients with a recent amputation.

Importance of T-Cell Proliferative Stress In Myelodysplastic Syndrome

AbstractAbstract 2939During thymic development, T-cells are produced with a large array of genetically diverse aβ T-cell receptors (TCRs) primed for robust antigen recognition. In patients with myelodysplastic syndrome (MDS), the functional T-cell repertoire becomes contracted and the CD4/CD8 ratio reduced possibly reflecting antigen stimulation. Dynamics within the T-cell compartment are regulated by progressive telomere shortening that occurs with proliferation. Preservation of telomere length is mediated by the telomerase (hTERT) enzyme. In MDS, we previously showed that telomere length in peripheral blood mononuclear cells (PBMCs) was significantly reduced among cases compared to controls. We hypothesized that dysregulated telomere maintenance due to proliferative stress contributes to contraction of the T-cell compartment. First, we examined telomerase mRNA expression and telomerase activity in purified T-cells in a cohort of 32 healthy individuals. The age of these donors ranged from 17 to 82 years with a mean age of 58 years. CD3+ T-cells were separated from the peripheral blood by negative selection (Miltenyi Biotech Corp) and measurements were made in both unstimulated and stimulated cells or 3 days with CD3/CD28 T-cell expanders (Dynabeads®) to induce proliferation. hTERT expression was measured by quantitative RT-PCR (qRT-PCR) and telomerase enzymatic function was quantified by the Telomere Repeat Amplification Protocol (TRAP assay). We found that hTERT mRNA was low- to undetectable in unstimulated T-cells, but was significantly up-regulated by stimulation (1.71±1.45 vs 3.43±1.90, p<0.001). In stimulated T-cells, the amount of inducible hTERT transcription was inversely correlated with age (p=0.0086). Results of telomerase functional assays showed that the stimulated T-cells had dramatically increased telomerase activity compared with unstimulated cells (623.03±435.76 vs 3.71±6.37, p<0.001), but in contrast to hTERT, telomerase enzyme function did not changed with age (p=0.7). Individual purification and stimulation of CD4+ and CD8+ T-cells showed that CD4+ cells induced 4-fold greater increase in telomerase activity compared to CD8+ cells suggesting that the primary requirement for telomeric repair lies with highly proliferative CD4+ T-cells. Next, we measured DNA copy number of T-cell receptor excision circles (TRECs) in both unstimulated and stimulated T-cells as a function of age to determine the capacity of these cells to undergo proliferation in vitro. TRECs are episomal DNA fragments that do not transfer to daughter cells and are expressed exclusively in mature T-cells. After in vitro stimulation, TREC copy number decreased from a mean of 218 to 67 copies indicating that 2.9 population doublings (PD) had occurred within the 3-day incubation period. The number of PDs was maintained with age (p=0.26) suggesting that the proliferation capacity along with the telomerase function normally remains intact with age progression. These results varified the utility of applying TREC analysis to determine the proliferative history in vitro and in vivo. The proliferative history of peripheral T-cells in vivo was then determined in a separate cohort of healthy controls (n=63) age-matched to MDS patients (n=66) by comparing the change in the amount of TREC DNA in unstimulated cells. For every year increase in age, the log TREC values decreased by 0.05 DNA copies (p=0.0012) in healthy donors. In MDS patients, a 2-fold greater decline in TREC copy number occurred each year (0.099 unit decrease in TREC copies per year among cases, p<0.0001; 0.05 copies per year among controls, p=0.012) suggesting that T-cells in MDS patients have been exposed to more proliferative stress. Collectively, our results indicate that telomere maintenance is controlled normally in proliferating T-cells by inducing hTERT mRNA expression and by upregulating telomerase enzyme activity. In MDS cases, accelerated proliferative stress may contribute to repertoire contraction and CD4/CD8 ratio abnormalities. Disclosures:No relevant conflicts of interest to declare.

Medium-term follow-up of plaque incision and porcine small intestinal submucosal grafting for Peyronie's disease

The best surgical option for the management of severe cases of Peyronie's disease is currently a matter of debate. To determine medium-term outcomes and complications after treatment of severe Peyronie's disease by porcine small intestinal submucosa (SIS) grafts, we retrospectively reviewed 33 consecutive plaque incisions followed by 4-ply SIS grafting in 28 patients (2002-2009). Postoperative complications, penile length preservation, de novo ED, penile curvature correction and curvature recurrence rates were recorded. Median patient age was 54 years (38-69 years). Median preoperative curvature was 90° (30-90°) (stable for at least 6 months). Six patients (21%) had preoperative ED. There were few postoperative complications (no cases of infection, haematoma (n=2), penile hypoesthesia (n=1), patch rejection and migration (n=1)). Subjective penile shortening and de novo ED were observed in 7 (25%) and 3 (11%) patients, respectively. The success rate for the procedure (straight penis or curvature ≤20° and ability to have intercourse) was 67% (22/33). Four patients achieved curvature correction after a repeat procedure with a new SIS graft. Eleven patients experienced recurrence within 3 months of surgery. After a median follow-up of 9 months (3-94), 22 patients (79%) had a satisfactory curvature correction.

“Cut and run”. Rapid life saving amputation using fire service hydraulic cutting equipment in entrapped trauma victims

Background: We investigated the potential to utilise fire service hydraulic cutting equipment to effect life saving amputations in entrapped trauma victims. Materials and methods: After a successful pilot study using four cadaveric porcine hind-leg models; three fresh frozen bequeathed cadaveric lower limb specimens each underwent five guillotine amputations using the hydraulic cutting equipment and conventional war surgical techniques. Video-documentation of each guillotine amputation was studied to define the: (i) number of cutting actions required to complete the amputations without the need for other cutting instruments, (ii) total time to achieve a completed amputation, (iii) quality of cut and (iv) proximal extent of fracture propagation. Results: Our study confirms that this equipment would enable extrication from immediately life threatening circumstances between two and seven times quicker than conventional amputation techniques. Conclusion: The equipment allows effective access to facilitate maximal stump length preservation and protects attending staff and the injured patient from the dangers of conventional amputation techniques in these difficult circumstances.Keywords: Life saving; Amputation; Hydraulic; Cutting; Equipment

Outcomes Associated with the Internal Fixation of Long-Bone Fractures Proximal to Traumatic Amputations

Preservation of optimal residual limb length following a traumatic amputation can be challenging. The purpose of this study was to determine if acceptable results can be achieved by definitive fixation of a long-bone fracture proximal to a traumatic amputation. We identified thirty-seven active-duty military service members who underwent internal fixation of a long-bone fracture proximal to a traumatic amputation. Functional status was assessed with the Tegner activity level scale and prosthesis use. Secondary outcome measures were the development of nonunion, infection, and heterotopic ossification. Twelve patients (32%) underwent amputation and fracture in the same osseous segment. Ten patients (27%) sustained bilateral traumatic amputations, and eight (22%) had a major fracture of the contralateral extremity. The median times to fracture fixation and amputation closure were twelve days and nineteen days, respectively, after the injury. The mean Tegner activity score was 3.32 (range, 1 to 6); patients with isolated extremity injuries had significantly higher Tegner scores than those with severe bilateral injuries (3.59 and 2.38, respectively; p = 0.04). Thirty-three patients (89%) developed an infection requiring surgical debridement. However, all fractures were treated until union occurred, and amputation level salvage was successful in all instances. Heterotopic ossification developed in twenty-eight patients (76%), with operative excision required in eleven patients (39%). High complication rates, but acceptable final results, can be achieved with internal fixation of a fracture proximal to a traumatic amputation to preserve functional joint levels or salvage residual limb length.

Approximation of plane curves by circular arcs

A method is proposed for approximating plane curves by circular arcs with length preservation. It is proved that, under certain rather mild constraints, any C 3-smooth curve (open or closed, possibly, with self-intersections) can be approximated by a C 1-smooth curve consisting of smoothly joined circular arcs. The approximation passes through interpolation nodes where it is tangent to the original curve, with the arc lengths between the nodes being preserved. The error of the approximation is estimated, and numerical examples are presented.

An Optimization Based Framework for Human Pose Estimation

In computer vision community, human pose estimation and nonrigid shape recovery have evolved into different subfields. The state-of-the-art optimization techniques have been applied to the problem of deformable surface reconstruction successfully and recent methods in this area have focused on designing formulations that are easier to solve. In general, these techniques lay their success on the assumption that sufficient 2-D-3-D correspondences can be detected. By contrast, confronted with the similar ambiguity problem, many techniques for human pose estimation adopt stochastic searching or discriminative predictions, which allow for more generative image cues. However, the global optimization cannot be guaranteed via the stochastic methods; and discriminative techniques usually suffer from inaccuracy. In this letter, we absorb ideas from both domains and propose a unified approach for articulated human pose estimation. Specifically, we optimize the human pose to account for the discriminative pose prediction, bone length preservation in parallel with the point-topoint image observation. Moreover, the L2 norm minimization is solved iteratively as a linear system with high computational efficiency.