Prolonged Healing Time Research Articles

Cellular and Molecular Factors Influencing Tendon Repair.

Tendons are complex connective tissues that transmit tensile forces between muscles and tendons. Tendon injuries are among the most common orthopedic problems with long-term disability as a frequent consequence due to prolonged healing time. Furthermore, the repair tissue is of inferior quality, predisposing patients to high rates of recurrence following initial injury. Coordinated cellular processes and biological factors under the influence of mechanical loading are involved in tendon healing and our understanding of these events lags behind other musculoskeletal tissues. Tendons are relatively hypocellular and hypovascular, with little or no intrinsic regenerative capacity. Studies have documented fatty degeneration, chondrogenic dysplasia, and ectopic ossification within tendon repair tissue. The underlying pathogenesis for these metaplastic changes that compromise the quality of tendon repair tissue is poorly understood. The purpose of this review is to compile literature reporting molecular processes that regulate/control the phenotype of cells responsible for abnormal matrix deposition at repair site. In addition, recent studies reporting the interplay of mechanotransduction and cellular responses during tendon repair are summarized. Identifying the links between cellular, biological, and mechanical parameters involved in tendon repair is paramount to develop successful therapies for tendon healing.

Healing time and incidence of hypertrophic scarring in paediatric scalds

IntroductionScald burns, which heal in less than 14 days, are seen to be at low risk of hypertrophic scar (HTS) formation. Consequently surgery is usually reserved for scalds likely to take more than 14 days to heal. With the use of silver based dressings over the past few years, anecdotally, we have observed a tendency to improved healing of scalds with conservative management and reduced need for surgical intervention. We aimed to investigate the effect of overall healing time of paediatric scalds on HTS formation over a five-year period (2011–15). MethodsWe retrospectively identified all new patients attending the Royal Children's Hospital (RCH) burns clinic from 31st January 2011–31st July 2015. Medical histories were reviewed for burns caused by scalds. Scar quality was determined from written records or clinical photographs. Patients were compared in groups based on healing time of <10 days, 10–14 days, 15–21 days, 22–30 days or >30 days. ResultsWe studied 322 children, of which 52 (16.1%) developed HTS. There was a significantly higher incidence of HTS with increased time to healing (mean 34.5 days compared to 12.1 days, p<0.01). There were 25 patients that underwent surgical treatment with excision or debridement and split thickness skin graft of which 21 (84%) developed HTS. Grafting offered no benefit in HTS rate in the 22–30 days to heal group. ConclusionsOur study confirms that there is a link between prolonged healing time of scald wounds and HTS. The danger of slow healing for scarring despite grafting, suggests this operation should be performed earlier than current practice to allow complete healing in less than 3 weeks.

Konjac glucomannan/polyacrylamide bicomponent hydrogels: Self-healing originating from semi-interpenetrating network

Abstract A novel self-healing semi-interpenetrating network hydrogel based on a natural polymer (konjac glucomannan, KGM) and synthetic polymer (polyacrylamide, PAAm) is prepared by a simple one-pot synthesis method. The hydrogels show excellent self-healing ability at ambient temperature without the need for any stimulus or healing agent and high recovery degrees (up to 73% tensile strength) can be achieved at a prolonged healing time. The healed gels exhibit high tensile strength (up to 66 kPa) and high elongation (up to 1200%). And the effect of the NH 3 ·H 2 O content, the ratio of KGM to acrylamide (AAm) and the cross-linker content on the self-healing efficiency have been investigated. The combination of structural transition of PAAm and the intermolecular hydrogen bonding is essential for self-healing property of the hydrogels.

Clinical Evaluation of Wound Healing in Split-Skin Graft Donor Sites Using Microscopic Quantification of Reepithelialization

Impaired or delayed wound healing is a common health problem. However, it remains challenging to predict whether wounds in patients will heal without complication or will have a prolonged healing time. In this study, the authors developed an objective screening tool to assess wound healing using microscopic quantification of reepithelialization in a split-thickness skin graft wound model and used this tool to identify risk factors for defective wound healing. Thirty patients (16 male and 14 female) were included in this prospective study. Anterior thigh skin biopsies from the donor site region of partial-thickness skin grafts were dressed with moisture-retentive dressings, and biopsies were examined on days 0, 2, 5, and 10 postoperatively by microscopy. Images were then transferred to a computer for image analysis and epithelial measurements (epithelial thickness and total reepithelialized surface). The effects of gender, age, body mass index, and smoking behavior on these wound healing parameters were determined. The authors found comparable results for the computer and traditional measure methods. However, the time required to perform the measurements using the semiautomated computer method was less than half the time of the traditional method. Image capturing, enhancing, and analysis with the new method required approximately 2 minutes 30 seconds, whereas the traditional methods took up to 7 minutes per image. The total size of the reepithelialized surface (P = .047) and percentage of the biopsy resurfaced with epithelia (P = .011) at day 10 were both significantly higher in male patients compared with female patients. In patients younger than 55 years, reepithelialized areas were significantly thicker than in patients older than 55 years (P = .008), whereas the size of the reepithelialized surface showed no differences. No significant differences in reepithelialization parameters were found concerning body mass index and smoking behavior. Both male gender and older age impair reepithelialization rate and epithelial thickness in partial-thickness skin graft donor site wounds. In contrast, body mass index and smoking behavior have not been shown to be influencing factors on reepithelialization. Thus, microscopic quantification of reepithelialization might be a suitable method for predicting complications associated with wound healing.

Exploring thermal anisotropy of cortical bone using temperature measurements in drilling.

Bone drilling is widely used in orthopaedics for fracture treatment, reconstructive surgery and bone biopsy. Heat generation in bone drilling can cause rise in bone temperature resulting in prolonged healing time or loosening of fixation. The purpose of this study was to investigate thermal anisotropy of bone by measuring the level of temperature in bone drilling with and without cooling conditions in two anatomical directions. Drilling tests were performed on bovine cortical bone. Atotal of fifteen specimens were used to obtain data for statistical analysis. Temperature near the cutting zone was measured in two anatomical directions. i.e. along the longitudinal and circumferential direction. Temperature distribution was also found in the two prescribed directions. Analysis of variance (ANOVA) was used to identify significant drilling parameter affecting bone temperature. Drilling speed, feed rate and drill size were found influential parameters affecting bone temperature. Higher drilling speed, feed rate, and large drill size were found to cause elevated temperature in bone. Much lower temperature was measured in bone when cooling fluid was supplied to the drilling region. Experimental results revealed lower temperatures in the circumferential direction compared to the longitudinal direction. Thermal anisotropy for heat transport was found in the bone. This study recommends lower drilling speed and feed rate and cooling for controlling rise in bone temperature.

Clinical Results and Complications of Lower Limb Lengthening for Fibular Hemimelia: A Report of Eight Cases.

Fibular hemimelia is a rare but the most common congenital long bone deficiency, encompassing a broad range of anomalies from isolated fibular hypoplasia up to substantial femoral and tibial shortening with ankle deformity and foot deficiency. Most cases of fibular hemimelia manifest clinically significant leg length discrepancy (LLD) with time that requires adequate correction by bone lengthening for stable walking. Bone lengthening procedures, especially those for pathological bones, are sometimes associated with severe complications, such as delayed consolidation, fractures, and deformities of the lengthened bones, leading to prolonged healing time and residual LLD at skeletal maturity. The purpose of this study was to review our clinical results of lower limb lengthening for fibular hemimelia.This study included 8 Japanese patients who diagnosed with fibular hemimelia from physical and radiological findings characteristic of fibular hemimelia and underwent single or staged femoral and/or tibial lengthening during growth or after skeletal maturity. LLD, state of the lengthened callus, and bone alignment were evaluated with full-length radiographs of the lower limb. Previous interventions, associated congenital anomalies, regenerate fractures were recorded with reference to medical charts and confirmed on appropriate radiographs. Successful lengthening was defined as the healing index <50 days/cm without regenerate fractures.A significant difference was observed in age at surgery between successful and unsuccessful lengthening. The incidence of regenerate fractures was significantly correlated with callus maturity before frame removal. LLD was corrected within 11 mm, whereas mechanical axis deviated laterally.Particular attention should be paid to the status of callus maturation and the mechanical axis deviation during the treatment period in fibular hemimelia.

Long-term radiographic follow-up of bisphosphonate-associated atypical femur fractures.

To evaluate the appearance of bisphosphonate-related femur insufficiency fractures on long-term follow-up radiographic studies and to describe the rate of fracture line obscuration and cortical beak healing over time. In this retrospective study, bisphosphonate-related femur fracture radiographs were reviewed by two radiologists for the presence of a fracture line, callus, and the characteristic cortical beak. Kaplan-Meier curves were used to analyze the time to first indication of healing. Femurs were also subdivided into those who underwent early versus late surgical fixation and those who underwent early versus late discontinuation of bisphosphonate. Clinical data including pain level and medication history were collected. Forty-seven femurs with a bisphosphonate-related femur fracture were identified in 28 women. Eighty-five percent took a bisphosphonate for greater than 5 years and 59 % for greater than 10 years. The median time to beak healing was 265 weeks and the median time to fracture line healing was 56 weeks in the 31 femurs with a baseline fracture. No statistically significant difference was identified between surgical fixation and conservative management. Bisphosphonate-related fractures demonstrate notably prolonged healing time on long-term follow-up.

Excision and primary closure of sacrococcygeal pilonidal sinus using suction drain

Background: Sacrococcygeal pilonidal sinus is a debilitating condition mostly affecting hairy males. The treatment of the condition is mainly surgical. Though various surgical methods are available but each has its own limitations like prolonged healing time and recurrence. We employed a simple technique which resulted in minimal complication rate and good results. Methods: Between 2011 and 2014 we operated 40 patients for sacrococcygeal pilonidal sinus. Thirty eight patients were males and 2 females between ages of 18 to 45 years. Patients underwent excision of the sinus with primary closure of the wound over a suction drain. Patients were discharged next day along with drain. Drain was removed on 7 th day and sutures removed on 14 th day. Patients were followed for 6 months. Results: Mean operative time was 40 minutes. One patient has accidental removal of drain in the first postoperative day which led to subsequent wound infection and prolonged healing. Rest of the patients had an uneventful postoperative course with no wound complications, nice wound healing and no recurrences over a period of 6 months. Conclusions: The method we described is simple, less time consuming, has short hospital stay, cost-effective and has excellent results.

Impact of Foot Infection on Infrainguinal Bypass Outcomes in Patients With Limb-Threatening Ischemia

Despite advances in endovascular therapy, infrainguinal bypass (IB) continues to play a major role in achieving limb salvage in the patients with extensive tissue loss and long-segment occlusive disease. In this study, we sought to compare the outcomes of IB in patients with limb-threatening ischemia who presented with or without foot infection. We conducted a retrospective cohort study of patients who underwent IB for limb-threatening ischemia at a single institution. Patient-related end points of interest included long-term mortality, 6-month readmission, and postoperative length of stay (LOS). Limb-related end points included major amputation (transfemoral, transtibial, or through the knee) and time to wound healing. Multivariable Cox, logistic, and robust regression were used to model time-to-event outcomes, readmission rates, and LOS respectively. Overall, 454 IB procedures that occurred over a 7-year period were analyzed. Demographics and baseline patient characteristics were similar between the infection and noninfection group, except congestive heart failure and diabetes were more common in the infection group. Presence of foot infection had no impact on mortality (HR, 0.72; P = .113). Statistically significant predictors of long-term mortality included increasing age, hypoalbuminemia, and congestive heart failure, whereas preoperative use of clopidogrel was protective (Table I). The presence of foot infection was an independent predictor of major ipsilateral amputation (HR, 1.86; P = .002). Other significant predictors of major amputation on multivariable analysis included history of statin administration, decreasing age, and low body mass index (Table I). In addition, foot infection was an independent predictor of prolonged LOS (mean LOS was 1.7 days longer in patients with vs those without infection; P < .001). Other independent predictors of prolonged LOS included intraoperative blood loss and reoperation in the index extremity; whereas, history of continuous preoperative aspirin use, normal renal function, and normal albumin levels were associated with decreased LOS (Table II). Readmission was influenced by the performance of a reoperation in the index extremity (OR, 2.57; P < .001) and history of diabetes (OR, 1.5; P = .023) but not the presence of foot infection (OR, 1.27; P = .192) There was a strong trend for prolonged wound healing time in patients with diabetes (HR, 1.57; P = .05), but not in those with foot infection (OR, 0.73; P = .36). Among patients requiring infrainguinal bypass for limb-threatening ischemia, infection was more common in patients with diabetes and was a significant predictor of major amputation and prolonged LOS. Infection was not predictive of mortality, wound healing time, or readmission. These findings lend additional support to the inclusion of infection in risk-stratification schemes for patients with limb-threatening ischemia, as recommended in the Society for Vascular Surgery WIfI Classification System, because of its adverse impacts on limb salvage.Table ISignificant predictors of mortality and major amputation among those undergoing infrainguinal bypassVariableHazard ratio95% Confidence intervalP valueMortality Age1.041.02-1.07<.001 Congestive heart failure2.061.26-3.36.004 Albumin0.610.45-0.82.001 Clopidogrel0.430.25-0.74.003Major amputation Infection1.861.25-2.78.002 Age0.960.93-0.99.025 Body mass index0.940.91-0.98.014 Statin1.921.14-3.24.014 Open table in a new tab Table IISignificant predictors of postoperative length of stay (LOS) among those undergoing infrainguinal bypass (IB)VariableCoefficient95% Confidence intervalP valueInfection1.660.76-2.55<.001Glomerular filtration rate−0.02−0.043 to −0.014<.001Aspirin−1.16−2.13 to −0.18.02Albumin−1.35−2.11 to −0.60<.001Redo-open1.360.49-2.24.02Operating room estimated blood loss0.0030.001-0.004<.001 Open table in a new tab

Radiation-associated Fractures

High-dose radiation is injurious to bone and is a known risk factor for the development of late fracture. Management of radiationinduced fractures is generally thought to be difficult, with prolonged healing times and a high nonunion rate. There is a relative paucity of literature to guide treatment. Fractures of the long bones typically should be managed with intramedullary nailing. A low threshold should exist for supplemental bone grafting, and a vascularized fibula graft should be considered for persistent nonunion. To prevent refracture, fixation should be left in situ indefinitely. Resection of the fracture site and reconstruction with an oncologic endoprosthesis is an effective salvage procedure. Periarticular fractures should be treated with joint arthroplasty, which allows early mobilization and avoids prolonged healing times. Fractures of expendable bones, primarily the clavicle, typically should be managed with debridement or resection.

Design of A Smartphone Application for Automated Wound Measurements for Home Care

Background: There are 8.5 million Americans who suffer from a chronic wound. Due to the lack of an objective system to measure and characterize wounds, the current standard of care relies highly on provider guesswork. This leads to misinformed care decisions, ultimately leading to prolonged healing times and high healthcare expenditures. Objective: This study describes the design and validation of a smartphone image-based system for accurately measuring and characterizing chronic wounds in an automated and objective fashion. Methods: Photos (n=81) were collected by the study team from patients (n=25) at the Johns Hopkins Bayview Wound Clinic in an IRB-approved study. Photos were taken using a variety of smartphones such that our training data set would include nuances of different smartphone cameras. We combined supervised image classification and computer vision to detect wound edges and segment the tissues within the wound. 15 individuals (“raters”) with various levels of training were then instructed to trace wound regions in a diverse subset of the wound images arbitrarily selected by the study team (n=10). The ensemble wound edge and tissue segmentation algorithms were compared against an 80% inter-rater gold standard. Results: The automated method resulted in a sensitivity = 98.31 ± 2.18 and specificity = 92.06 ± 7.86). In contrast, the ruler-based measurement resulted in sensitivity = 1 ± 0, Specificity = 0.57 ± 0.30. A normalized area measurement for the automated method resulted in a normalized area of 1.14 ± 0.17. In comparison, the standard of care method resulted in a normalized area of 1.86 ± 0.30 relative to gold standard. With respect to tissue segmentation, the overall average tissue classification accuracy on k-fold cross validation using the sparse neural network method is 93.6% ± 3.3%. Conclusions: The result illustrates the large overestimation of wound size that occurred when the wounds were measured using the ruler measurement. It also corroborates the literature-reported value of measurement inaccuracy by standard methods. Our study shows the feasibility of an easily deployed smartphone system to classify wounds in an automated manner with high accuracy. Such a system could be used to objectify measurements by nurses in the home care environment, thus improving the accuracy of wound care and, potentially, the outcomes of patients.

Cost analysis of inappropriate treatments for suspected dermatomycoses

Superficial mycoses are estimated to affect more than 20-25% of the world’s population with a consistent increase over the years. Most patients referred to our clinic for suspected dermatomycoses have already been treated with pharmacotherapy, without a previous mycological examination and many show changes in the clinical manifestations. Indeed, some medications, such as steroids, antiviral, antibiotics and antihistamines are not able to erase a fungal infection, but also they can cause atypical clinical manifestations. The consequences of inappropriate treatment include delayed diagnosis, prolonged healing time, and additional costs. The aims of this study were (1) to evaluate the incidence of increased costs attributable to inappropriate therapy sustained by the National Health Service and patients and (2) to highlight the importance of mycological evaluation before starting treatment, in order to improve diagnostic accuracy. An observational retrospective and prospective study was performed from September 2013 to February 2014, in 765 patients referred to our center (University Hospital “ Federico II”) in Naples, Italy, for suspected mycological infection. The following treatments (alone or in combination) were defined as inappropriate: (1) cortisone in a patient with at least one positive site; (2) antifungals in (a) patients with all negative sites or (b) ineffective antifungal treatment (in terms of drug chosen, dose or duration) in those with all positive sites; or (3) antibiotics; (4) antivirals or (5) antihistamines, in patients with ≥ 1 positive site. Five hundred and fifty patients were using medications before the assessment visit. The total amount of avoidable costs related to inappropriate previous treatments was € 121,417, representing 74% of the total treatment costs. 253/550 patients received drugs also after the visit. For these patients, the cost of treatment prescribed after mycological testing was € 42,952, with a decrease with respect to the total consumption of drugs at the time of access to the Mycology Laboratory of € 34,781. Thus, our cost analysis shows that it is important to obtain a reduction of costs for pathologies that need to be confirmed by examinations before starting treatment.

Excision and Patch Grafting of a Lateral Peyronie's Plaque-Utilizing a Longitudinal "Window" Approach.

IntroductionPeyronie’s disease (PD) is a debilitating disorder in which collagen deposition, fibrosis, and plaques in the tunica albuginea result in penile curvature, shortening, and pain. For severe curvatures requiring plaque incision or excision with grafting (PIEG), a subcoronal circumcising incision with penile degloving has historically been used.AimsThe aim of this study was to report our unique approach to PIEG via a longitudinal “window” incision for the correction of PD, minimizing the surgical manipulation and dissection accompanying the traditional circumcising incisional approach that may lead to increased postoperative edema, pain, and prolonged healing time.MethodsA patient presented with a stable, painless, 90-degree midshaft leftward curvature causing penetration difficulties and painful intercourse for his partner. His Sexual Health Inventory for Men (SHIM) score was 23. The patient opted for surgical correction with plaque excision and grafting via a 4-cm longitudinal incision overlying the point of maximal curvature along the left lateral penile shaft. This direct access to the left corpus cavernosum and plaque, along with dissecting skin, dartos, and Buck’s fascia, created a window with sufficient exposure for excision and patch grafting.Main Outcome MeasuresThe main outcome measures were objective data and subjective data in men undergoing PIEG via lateral longitudinal “window” incision for PD repair.ResultsThe plaque was excised and a porcine small intestinal submucosa graft was sewn in. Intraoperative artificial tumescence at the end of surgery revealed complete correction of the curvature. The patient experienced painless rigid erections by postoperative day three with minimal penile edema. By postoperative week four, he could successfully partake in coitus. His SHIM score remained unchanged. At maximum follow-up 6 months postoperatively, he still endorsed excellent cosmetic and functional outcomes with spontaneous unassisted erections and no recurrence of his curvature.ConclusionA lateral longitudinal incision for PIEG is a feasible technique and may reduce the postoperative morbidity and dissection required with traditional circumcising incision with penile degloving. Larger comparative studies are necessary for further evaluation.

Stimulating angiogenesis mitigates the unloading-induced reduction in osteogenesis in early-stage bone repair in rats.

Accelerating fracture healing during bed rest allows early mobilization and avoids prolonged fracture healing times. We tested the hypothesis that stimulating angiogenesis with deferoxamine (DFO) mitigates the unloading-induced reduction in early-stage bone repair. Rats aged 12 weeks were subjected to cortical drilling on their tibial diaphysis under anesthesia and treated with hindlimb unloading (HU), HU and DFO administration (DFOHU), or weight bearing (WB) for 5 or 10 days (HU5/10, DFOHU5/10, WB5/10; n = 8 per groups) until sacrifice for vascular casting with a zirconium dioxide-based contrast agent. Taking advantage of its absorption discontinuity at the K-absorption edge, vascular and bone images in the drill-hole defects were acquired by synchrotron radiation subtraction CT. Bone repair was reduced in HU rats. The bone volume fraction (B.Vf) was 88% smaller in HU5 and 42% smaller in HU10 than in WB5/10. The bone segment densities (B.Seg) were 97% smaller in HU5 and 141% larger in HU10 than in WB5/10, and bone thickness (B.Th) was 38% smaller in HU10 than in WB10. The vascular volume fraction (V.Vf) was 35% and the mean vessel diameter (V.D) was 13% smaller in HU10 than in WB10. When compared according to categorized vessel sizes, V.Vf in the diameter ranges 20–30, 30–40, and >40 μm were smaller in HU10 than in WB10, and V.Seg in the diameter range >40 μm was smaller in HU10 than in WB10. In contrast, there was no difference in B.Vf between DFOHU5/10 and WB5/10 and in V.Vf between DFOHU10 and WB10, though B.Seg remained 86% smaller in DFOHU5 and 94% larger in DFOHU10 than in WB5/10, and B.Th and V.D were 23% and 14% lower in DFOHU10 than in WB10. Vessel size-specific V.Vf in the diameter ranges 10–20 and 20–30 μm was larger in DFOHU5 than in HU5. In conclusion, the enhanced angiogenic ingrowth mitigates the reduction in bone repair during mechanical unloading.

Treating Atypical Femoral Fractures Related to Bisphosphonates.

Doctors widely prescribe osteoclast-inhibiting bisphosphonate drugs to treat osteoporosis, but long-term bisphosphonate use has been linked to an increased risk of atypical subtrochanteric femoral fractures. According to an updated task force report from the American Society for Bone and Mineral Research, the features that distinguish these atypical subtrochanteric fractures include transverse orientation, general lack of comminution, and localized cortical thickening at the fracture site. In addition, the prolonged healing times of these fractures challenge orthopaedists to obtain strong and stable fixation that outlasts the extended period required for fracture union. Intramedullary nailing is often used to treat these fractures, but related characteristics such as canal narrowing can make this fixation approach unfeasible. This month’s “Case Connections” looks at various techniques for repairing bisphosphonate-associated atypical femoral fractures. In the January 14, 2015, JBJS Case Connecto r , Yuasa et al. reported on the case of a sixty-nine-year-old woman who, one month prior to scheduled right hip arthroplasty to treat osteoarthritis, presented with severe right thigh pain after a low-trauma fall. History-taking revealed four-plus years of treatment with alendronate (Fosamax), and radiographs showed a noncomminuted transverse subtrochanteric fracture below an arthritic hip joint. During a single operation, the patient underwent cementless total hip arthroplasty using a modular stem/neck, followed by fracture reduction and fixation using a cable-and-plate system (Fig. 1). The patient was switched from alendronate to a …

A Novel Solution to Securing Nasogastric Feeding Tubes in Pediatric Burn Patients

Aims: To present a novel method of securing nasogastric (NGT) feeding tubes in pediatric burn patients. Presentation of Case: We have developed an arrangement of tube, twill tie and suture, to secure a feeding tube in position, in which a twill tie is secured around the patient’s head and interwoven into the burn dressing. The NGT is secured to the twill tie via a locking suture. Discussion: Nasogastric feeding tubes are important in pediatric burn patients to facilitate the healing process by meeting their increased metabolic demand for protein and calories. These tubes are typically secured via tape to the face, but in patients with facial burns tape may not adequately anchor the feeding tube, allowing for unintended dislodgement of the NGT. Inadvertent removal of nasogastric tubes places patients at risk for complications including prolonged healing time and aspiration, as well as the need for replacement of the NGT.

Demineralized Bone Matrix Injection in Consolidation Phase Enhances Bone Regeneration in Distraction Osteogenesis via Endochondral Bone Formation.

BackgroundDistraction osteogenesis (DO) is a promising tool for bone and tissue regeneration. However, prolonged healing time remains a major problem. Various materials including cells, cytokines, and growth factors have been used in an attempt to enhance bone formation. We examined the effect of percutaneous injection of demineralized bone matrix (DBM) during the consolidation phase on bone regeneration after distraction.MethodsThe immature rabbit tibial DO model (20 mm length-gain) was used. Twenty-eight animals received DBM 100 mg percutaneously at the end of distraction. Another 22 animals were left without further procedure (control). Plain radiographs were taken every week. Postmortem bone dual-energy X-ray absorptiometry and micro-computed tomography (micro-CT) studies were performed at the third and sixth weeks of the consolidation period and histological analysis was performed.ResultsThe regenerate bone mineral density was higher in the DBM group when compared with that in the saline injection control group at the third week postdistraction. Quantitative analysis using micro-CT revealed larger trabecular bone volume, higher trabecular number, and less trabecular separation in the DBM group than in the saline injection control group. Cross-sectional area and cortical thickness at the sixth week postdistraction, assessed using micro-CT, were greater in the regenerates of the DBM group compared with the control group. Histological evaluation revealed higher trabecular bone volume and trabecular number in the regenerate of the DBM group. New bone formation was apparently enhanced, via endochondral ossification, at the site and in the vicinity of the injected DBM. DBM was absorbed slowly, but it remained until the sixth postoperative week after injection.ConclusionsDBM administration into the distraction gap at the end of the distraction period resulted in a significantly greater regenerate bone area, trabecular number, and cortical thickness in the rabbit tibial DO model. These data suggest that percutaneous DBM administration at the end of the distraction period or in the early consolidation period may stimulate regenerate bone formation and consolidation in a clinical situation with delayed bone healing during DO.

Fractional nonablative laser resurfacing: is there a skin tightening effect?

Fractional photothermolysis, an approach to laser skin resurfacing that creates microscopic thermal wounds in skin separated by islands of spared tissue, was developed to overcome the high incidence of adverse events and prolonged healing times associated with full coverage ablative laser procedures. To examine whether fractional nonablative laser resurfacing induces skin tightening. A literature review was performed to evaluate the clinical and histologic effects of fractional nonablative laser resurfacing and full coverage ablative resurfacing procedures. Fractional nonablative lasers produce excellent outcomes with minimal risk and morbidity for a variety of clinical conditions, including photodamaged skin, atrophic scars, surgical and burn scars. Efforts to induce robust fibroplasia in histologic specimens and skin tightening in the clinical setting have yielded inconsistent results. A better understanding of the histology of fractional laser resurfacing will help to optimize clinical outcomes.

Presence of lymphatics in a rat tendon lesion model.

Tendons lack sufficient blood supply and represent a bradytroph tissue with prolonged healing time under pathological conditions. While the role of lymphatics in wound/defect healing in tissues with regular blood supply is well investigated, its involvement in tendon defects is not clear. We here try to identify the role of the lymphatic system in a tendon lesion model with morphological methods. A rat Achilles tendon lesion model (n = 5) was created via surgical intervention. Two weeks after surgery, animals were killed and lesioned site removed and prepared for polarization microscopy (picrosirius red) and immunohistochemistry using the lymphatic markers PROX1, VEGFR3, CCL21, LYVE-1, PDPN, and the vascular marker CD31. Additionally, DAPI was applied. Untreated tendons served as controls, confocal laser-scanning microscopy was used for documentation. At the lesion site, polarization microscopy revealed a structural reintegration while immunohistochemistry detected band-like profiles immunoreactive for PDPN, VEGFR3, CCL21, LYVE1, and CD31, surrounding DAPI-positive nuclei. PROX1-positive nuclei were detected within the lesion forming lines and opposed to each other. These PROX1-positive nuclei were surrounded by LYVE-1- or VEGFR3-positive surfaces. Few CD31-positive profiles contained PROX1-positive nuclei, while the majority of CD31-positive profiles lacked PROX1-positive nuclei. VEGFR3-, PDPN-, and LYVE-1-positive profiles were numerous within the lesion site, but absent in control tissue. Within 2 weeks, a structural rearrangement takes place in this lesion model, with dense lymphatic supply. The role of lymphatics in tendon wound healing is unclear, and proposed model represents a good possibility to study healing dynamics and lymphangiogenesis in a tissue almost completely lacking lymphatics in physiological conditions.

Outcomes of open reduction and internal fixation of acute proximal pole scaphoid fractures.

Proximal pole scaphoid fractures are less common than waist fractures, and successful management can be difficult. We hypothesize that time to union is increased by delays in surgical fixation, greater initial displacement, and higher energy mechanisms of injury. A retrospective review was conducted of all patients undergoing open reduction internal fixation (ORIF) of acute proximal pole scaphoid fractures at our institution over a 19-year period. A review of clinical as well as radiographic data was undertaken. The mechanism of injury, patient demographics, timing of surgery, initial displacement, fixation method, smoking status, and lunate morphology were recorded. Functional outcome measures were recorded when available. Univariate analysis using Kaplan-Meier survival curves was performed. A total of 10 out of 23 patients (43%) showed evidence of union at 14weeks post-injury. Rates of early union were higher in non-displaced fractures (70%) when compared to displaced fractures (23%). Similarly, fractures sustained via low energy mechanisms had a higher rate of early union compared to high energy mechanisms (69 versus 10%). A delay in ORIF did not appear to influence rate of union. Initial displacement and mechanism of injury have the most significant effects on early rates of union. Delay in ORIF of up to 28days did not affect the rate of initial union, but the authors recommend early fixation of these fractures to prevent further displacement. Patients with widely displaced fractures or those with high energy mechanisms should be counseled regarding prolonged healing time. IV-therapeutic.