Donor Site Infection Research Articles

Abstract 63: Mepilex Ag versus Xeroform as Dressings for Split-Thickness Skin Graft Donor Sites

PURPOSE: Split-thickness skin grafting (STSG) is one of the most common procedures in reconstructive and burn surgery; the optimal management of the donor site remains a source of debate and inconsistency in the care of these patients. The optimal donor site dressing is one that minimizes pain and the risk of infection. In this study, we aim to compare postoperative pain and the rate of donor site infection between bismuth tribromophenate gauze (Xeroform) dressings and silver-impregnated foam dressings (Mepilex Ag, Mölylnke, Gothenburg, Sweden) for STSG donor sites in burn patients. METHODS: We performed retrospective chart review of 212 patients with burn injuries treated in our burn unit in 2017. Patients who underwent debridement and autografting with STSG were classified by donor site dressing type (either Xeroform or Mepilex Ag). Infections were documented by clinical assessment and managed appropriately when noted. Maximum pain scores on postoperative days 1, 3, and 5 were recorded, using a patient-reported 10-point scale (pain scores for children under age 7 were recorded using FLACC scores). Univariate statistics were used to compare groups, and Barnard’s unconditional test was performed to compare the incidence of donor site infection between the groups. RESULTS: There were eighty-six cases of autografting with STSG. Of these, 37 had donor sites dressed with Mepilex Ag (43%), while 49 had donor sites dressed with Xeroform (57%). No infections were observed in donor sites dressed with Mepilex Ag (0%); five patients with Xeroform on their donor sites developed donor site infection (10%, p=0.03). There were no significant differences in maximum pain scores between Mepilex Ag and Xeroform groups on postoperative days 1, 3, and 5 (7.00 vs. 6.76, p=0.69; 6.30 vs. 6.15, p=0.81; and 5.71 vs. 5.81, p=0.89). Patients in the Mepilex Ag and Xeroform groups were similar in age, gender and length of stay (LOS). The Mepilex Ag group had somewhat lower percent total body surface area (TBSA) burned (6.8% vs. 10.4%, p=0.03). There were no significant differences in age, gender, LOS, percent TBSA, or pain scores in those who had infections and those who did not. CONCLUSIONS: Donor sites dressed with Mepilex Ag have a lower rate of donor site infection relative to those dressed with Xeroform in burn patients undergoing autografting with split-thickness skin grafts, though maximum pain scores on postoperative days 1, 3, and 5 remain similar.

346 Silver Impregnated Silicon Foam Dressing Leads to Fewer Donor Site Infections Compared to Petroleum Gauze: A Retrospective Review

346 Silver Impregnated Silicon Foam Dressing Leads to Fewer Donor Site Infections Compared to Petroleum Gauze: A Retrospective Review

Enhanced Recovery after Surgery Pathway for Microsurgical Breast Reconstruction: A Systematic Review and Meta-Analysis.

The enhanced recovery after surgery pathway was introduced in 1997 as a multimodal approach to reduce preventable postoperative harm and shorten hospital length of stay. However, there is yet no widely accepted enhanced recovery after surgery protocol for microsurgical breast reconstruction. The authors conducted a systematic review and meta-analysis of the current literature on enhanced recovery after surgery for microsurgical breast reconstruction with regard to postoperative length of stay and morbidity. The PubMed, Embase, Cochrane, Scopus, and Web of Science databases were searched for all studies published before June of 2016 containing original data on enhanced recovery after surgery in microsurgical breast reconstruction in relation to postoperative length of stay and morbidity. Studies were screened using eligibility criteria. Meta-analysis, odds ratio, and 95 percent confidence interval were used to pool acquired data. The initial search identified 86 studies. Two independent screeners identified four original articles with a total of 676 patients. Length of stay was significantly shorter for patients on an enhanced recovery after surgery pathway (mean difference, -1.23; 95 percent CI, -1.50 to -0.96; p < 0.001; I = 0 percent; random effects model). Enhanced recovery was not associated with changes in 30-day postoperative morbidity; specifically, no significant difference was observed in rates of partial flap loss (p = 0.44), total flap loss (p = 0.91), breast hematoma (p = 0.69), donor-site infection (p = 0.53), urinary tract infection (p = 0.29), and pneumonia (p = 0.42). The authors' review suggests that enhanced recovery after surgery in microsurgical breast reconstruction is associated with a reduced length of stay, and is not associated with increased postoperative morbidity.

Determination of Early Neurological Outcome by ASIA score following Delayed Anterior Decompression and Stabilization of Lower Cervical Spine Injury

Background: Surgical management of lower cervical spine injury is a very important issue among these patients.&#x0D; Objective: The purpose of the present study was todetermine the early neurological outcome of delayed anterior decompression and stabilization of lower cervical spine injury.&#x0D; Methodology: This cross sectional study was carried out in the Department of Neurosurgery at Dhaka Medical College and Hospital, Dhaka, Bangladesh within the period of January 2010 to July 2011 for a period of one year and 6 months. Neurological outcome following anterior decompression and stabilization of lower cervical spine injury was observe. Patients presented with lower cervical spine injury were included in this prospective study. Quantification of neurologic deficit in lower cervical spine injury patients were carried out by following The American Spinal Injury Association (ASIA) impairment scale. Early neurological outcome was also assessed after operation by using ASIA impairment scale in the follow up period at one, three and six months interval.&#x0D; Result: A total of 31 patients were included in this study. Based on the ASIA impairment scale, preoperatively, 6.4 5% of the injuries were grade A, 16.13 % of the injuries were Grade B, 16.13% of the injuries were Grade C and 35.48 % of the injuries were Grade D. early post-operative complications include dysphagia in 3 5.48% cases, donor site infection in 9.67% cases, CSF leak in 3.22%; catheter related urinary tract infection 9.67% and bed sore occurred in 6.45% cases.&#x0D; Conclusion: In conclusion significant neurological recovery can be expected following delayed anterior decompression and stabilization of lower cervical spine in lower cervical spine injury patient.&#x0D; Journal of National Institute of Neurosciences Bangladesh, 2018;4(2): 82-86

Use of a novel chitosan-based dressing on split-thickness skin graft donor sites: a pilot study.

Split-thickness skin graft (STSG) donor site dressings can play an integral role in reducing donor site morbidity. This study tested a novel, chitosan-based wound dressing, Opticell Ag, as an STSG donor site dressing for wounds <10% total body surface area (TBSA). Between January and December 2016, the chitosan-based dressing was placed on participating patients' donor sites immediately following graft harvest and covered with a transparent occlusive dressing. Pain was evaluated on postoperative day one, before dressing change between days 5-7, and before and after dressing removal between days 10-14 using the Visual Analog Scale (VAS). The extent of re-epithelialisation was determined between day 10-14 and at one month, and healing quality was also evaluated at one month post-operatively using the Vancouver Scar Scale (VSS). A total of 19 patients were recruited, of which 16 completed the study. Patients experienced mild-to-moderate pain in their donor sites when the chitosan-based dressing was used. Pain decreased significantly between postoperative day one and days 10-14, as well as between days 5-7 and 10-14. The mean percentage of re-epithelialisation on days 10-14 was 92% and by one month was 99%. The mean VSS at one month was 3.2±1.4. There were no statistically significant differences between patients' re-epithelialisation rates or VSS scores. There were unplanned dressing changes in four patients. No donor site infections or other adverse events were identified. The chitosan-based dressing tested in this study is safe, effective, and associated with reasonable pain control and acceptable healing quality. The results suggest that it is a promising STSG donor site dressing.

Prevention and management of bacterial infections of the donor site of flaps raised for reconstruction in head and neck surgery

PurposeIn the field of reconstructive head and neck surgery, surgical site infections (SSI) are commonly investigated for the recipient site of various reconstructive procedures. Data about SSI of the donor site of different flaps raised for reconstruction are rare. Material and MethodsWith regard to the bacterial donor site infections, we retrospectively investigated the medical data, surgical reports and wound management protocols of 267 patients who received reconstruction of the head and neck after ablative surgery. All patients underwent reconstruction with one of the following flaps: free fasciocutaneous radial forearm flap (RFFF), free fasciocutaneous anterolateral thigh flap (ALTFF), pedicled myocutaneous latissimus dorsi flap (PLDF), pedicled myocutaneous pectoralis major flap (PPMF), free osteocutaneous fibula flap (FFF). Follow-up was conducted for 12 months. ResultsThe lowest detection ratio (DR: number of infected sites/flaps raised from the respective donor site) was calculated for the radial forearm, 0.087. Pedicled flaps presented a moderate DR (PLDF: 0.27, PMMF:0.35). Donor sites of the leg possessed the highest DR (ALTFF:0.61, FFF: 045). Mainly gram-positive facultative anaerobic bacteria (n = 41) were detected and gram-negative bacteria (aerobe/anaerobe) were present in 27 cases. The most frequently detected bacteria were Staphylococcus spp., Viridans Streptococci, Pseudomonas aeruginosa and Escheria coli. Continuous wound management for in-hospital patients was able to prevent any local spreading or a prolonged length of in-hospital stay. ConclusionOverall, gram-positive facultative anaerobic bacteria, mainly Staphylococcus spp., are the predominant bacteria detected in donor site wounds. For wound care management, an infection with gram-negative pathogens should not be neglected.

Large Animal Models of an In Vivo Bioreactor for Engineering Vascularized Bone.

Reconstruction of large skeletal defects is challenging due to the requirement for large volumes of donor tissue and the often complex surgical procedures. Tissue engineering has the potential to serve as a new source of tissue for bone reconstruction, but current techniques are often limited in regards to the size and complexity of tissue that can be formed. Building tissue using an in vivo bioreactor approach may enable the production of appropriate amounts of specialized tissue, while reducing issues of donor site morbidity and infection. Large animals are required to screen and optimize new strategies for growing clinically appropriate volumes of tissues in vivo. In this article, we review both ovine and porcine models that serve as models of the technique proposed for clinical engineering of bone tissue in vivo. Recent findings are discussed with these systems, as well as description of next steps required for using these models, to develop clinically applicable tissue engineering applications.

The Role of Medial Femoral Condyle Free Vascularized Bone Graft for the Treatment of Failed Scaphoid Nonunion Surgery associated with Proximal Pole Avascular Necrosis

There is no financial information to disclose. Revision surgery for scaphoid nonunions with proximal pole avascular necrosis is a challenge. We hypothesize that the use of free-vascularized medial femoral condyle bone grafts can heal the bone, revascularize the proximal pole, and restore scaphoid architecture, resulting in acceptable functional outcomes. We retrospectively reviewed patients who had failed prior operative treatment for a scaphoid nonunion and proximal pole avascular necrosis. Between May of 2005 and September of 2016, 49 patients were identified with this preoperative diagnosis and subsequent treatment with a medial femoral condylar free vascularized bone flap. Mean time from injury to revision surgery was 24 months, and a mean 15 months following the initial surgery. Of the 49 patients, 36 had a prior bone graft procedure and 6 patients had two previous surgeries. Initial internal fixation was with a scaphoid screw in 43 patients and K-wires alone in 3. All patients had documented avascular necrosis of the proximal pole at the time of our surgery, defined by complete absence of punctate bleeding of the proximal pole with the tourniquet deflated. Carpal indices, time to union, functional outcomes and complications were recorded. Forty-one of 49 previously operated on scaphoid nonunions healed (84%) at a mean of 16 weeks (range, 9 to 31 weeks) based upon CT scan imaging. Radiographs demonstrated significant improvement in carpal alignment following surgery, as determined by the lateral scaphoid angle, scapholunate angle, radiolunate angle, scaphoid height to length ratio and carpal height ratio. There was a trend towards improved grip strength and no significant change in total wrist range of motion pre- and postoperatively. Twenty-nine patients underwent 21 subsequent planned procedures (removal of buried K wires). There were two superficial postoperative donor site infections, however no patients complained of medial thigh pain at final follow-up. Age, smoking status, BMI, time to surgery, or preoperative radiographic findings were not found to be statistically significant predictors of failure. •We present the largest series to date of patients who have undergone revision scaphoid nonunion surgery with documented avascular necrosis of the proximal pole.•84% of patients who had failed prior scaphoid nonunion surgery healed at a mean of 16 weeks after treatment with free-vascularized medial femoral condyle grafts.

Reconstruction of midface defects with the osteocutaneous radial forearm flap: Evaluation of long term outcomes including patient reported quality of life.

Maxillectomy defects significantly impair quality of life. Prosthetics can overcome some of these issues, but has limitations. The role of the osteocutaneous radial forearm free flap (OC-RFFF) has been established for reconstruction of smaller maxillectomy defects, but its role in larger defects is not well defined. We aim to evaluate outcomes after midface reconstruction utilizing the OC-RFFF. Retrospective review of prospective database collected between 2005 and 2014 of midface reconstruction using OC-RFFF in a tertiary care centre. Donor site complications and acute and long-term recipient site complications were measured. Health related quality of life was assessed using the University of Washington Quality of Life (UW-QOL) Questionnaire. A total of 68 midface defects were reconstructed using the OC-RFFF. Acute recipient site complications included three flap failures (4%), and two additional microvascular revision cases for vascular compromise. Late recipient complications included fistula (n = 10, 14%), ectropion (n = 7, 10%), diplopia (n = 6, 9%) and exposed hardware (n = 5, 7%). Resection of cheek skin or orbital rim correlated with orbital complications. The incidence of fistula was not affected by defect size or prior radiation. There were two donor site infections and no instances of forearm fracture. Patients undergoing OC-RFFF repair had mean scores for UW-QOL outcomes higher than published rates of obturator quality of life. The OC-RFFF is suited to a variety of midface defects and can be combined with hardware to reconstruct the orbital floor. Recipient site complications are common, but donor site morbidity is low and outcomes, including HR-QOL, are acceptable.

Nano-magnesium phosphate hydrogels: efficiency of an injectable and biodegradable gel formulation towards bone regeneration

The use of autografts is considered as gold standard for the treatment of bone tissue defects caused by tumor, disease or trauma. The second surgery for autologous bone harvesting is often linked to donor site morbidity, pain, blood loss and infections (1). To circumvent these issues, synthetic bone grafts made of either organic biopolymers such as poly lactic-co-glycolic acid (PLGA) or collagen (2) and inorganic replacement materials like calcium orthophosphate (CaP) bioceramics are commercially available and frequently used in the clinic (3). The variety of such materials in terms of composition and application form (e.g., pastes, blocks, granules) is huge but most of them do not fulfill all main criteria for adequate bone substitutes: osteogenesis, osteoinductivity, osteoconductivity and osseointegration. Only autologous bone seems to comply with those demands (4).

Split skin graft for diabetic ulcers: an analysis

Background: Most diabetic wounds are slow healing and have a considerable area for which healing takes a long duration by conservative methods. Hence we wanted to check the effectiveness of methods of accelerating the healing process. Aim of the study was to analyse the effectiveness of split skin grafting as a curative procedure in these ulcers. Methods: A retrospective analysis of 100 cases of diabetic ulcer who had undergone split skin grafting between 2009 and 2012 was performed to check the effectiveness of the procedure in curing the ulcer. Results: Split skin graft cured about 88% of the patients (graft take more than 90%) with recurrence of about 5%. The rest had graft taken less than 90% but the ulcer had healed. Donor site infection was seen in 5% and all were treated conservatively. Conclusions: The major goal in diabetic foot management programmes is to reduce morbidity, early wound healing and early ambulation. This procedure of split skin grafting helps to achieve this. But the ideal way forward is to avoid the development of such diabetic ulcers by patient education and improving glycemic control. Follow up in diabetic clinics should include vascular and neuropathic assessment of the foot and education about foot care.

The Use of a Mechanical Stapler in Jejunal Free Flaps in Laryngopharyngectomy Defects.

The Use of a Mechanical Stapler in Jejunal Free Flaps in Laryngopharyngectomy Defects.

Safety of the supraclavicular artery island flap in the setting of neck dissection and radiation therapy.

The supraclavicular artery island flap (SAIF) has recently been repopularized as a versatile and reliable option for reconstruction of oncological head and neck defects. Prior ipsilateral neck dissection or irradiation is considered a relative contraindication to its use. The aim of this study was to describe the safety and utility of the SAIF for head and neck reconstruction in the setting of neck dissection and radiation. A retrospective chart review was performed of consecutive SAIF reconstructions at two institutions between May 2011 and 2014. In addition to demographic data, comorbidities, indications, surgical characteristics, data about radiation treatment, and neck dissection were specifically recorded. Donor and recipient site complications were noted. Fisher exact test was performed to analyze if neck dissection or radiation were associated with complications. A total of 22 patients underwent SAIF reconstruction for an array of head and neck defects. Donor site infection was noted in one patient. Recipient site complications included, wound dehiscence (n = 2), orocutaneous fistula (n = 1), carotid blowout (n = 1), and total flap loss (n = 1). There was no association between prior neck dissection or radiation treatment and flap loss (p = 1.00). The SAIF is safe for use in patients who have had an ipsilateral neck dissection involving level IV or V lymph nodes and/or radiation treatment to the neck. It can be used alone or in combination with other flaps for closure of a variety of head and neck defects.

The role of patient's profile and allogeneic blood transfusion in development of post-cardiac surgery infections: a retrospective study.

We aimed to investigate the association of patient characteristics and allogeneic blood transfusion products in development of post-cardiac surgery nosocomial infections. This retrospective study was conducted in 7888 patients undergoing cardiac surgery with median sternotomy and cardiopulmonary bypass. Multivariable logistic regression analysis was used for independent effect of variables on infections. A total of 970 (12.3%) patients developed one or several types of postoperative infections. Urinary (n = 351, 4.4%) and pulmonary tract infections (n = 478, 6.1%) occurred more frequently than sternal wound infections (superficial: n = 102, 1.3%, deep: n = 72, 0.9%) and donor site infections (n = 61, 0.8%). Interventions, including valve replacement (P = 0.002) and coronary artery bypass grafting combined with valve replacement (P = 0.012), were associated with increased risk of several types of postoperative infections. Patients' profiles changed substantially over the years; morbid obesity (P = 0.019), smoking (P = 0.001) and diabetes mellitus (P = 0.001) occur more frequently nowadays. Furthermore, surgical site infections showed to be related to morbid obesity (P < 0.001) and higher risk stratification (P = 0.031). Smoking (P < 0.001) and chronic obstructive pulmonary disease (P < 0.001) were related to pulmonary tract infections. In addition, diabetic patients developed more sepsis (P = 0.003) and advanced age was associated with development of urinary tract infections (P < 0.001). Even after correcting for other factors, blood transfusion was associated with all types of postoperative infection (P < 0.001). This effect remained present in both leucocyte-depleted and non-leucocyte-depleted transfusion. Our data showed that post-cardiac surgery infections occur more frequently in patients with predetermined risk factors. The amount of blood transfusions was integrally related to every type of postoperative infection.

Autologous fat grafting and breast cancer recurrences: Retrospective analysis of a series of 100 procedures in 64 patients

Autologous fat transfer (AFT) enhances the cosmetic results of breast reconstruction and corrects breast conserving operation sequelae. The question of its oncological safety remains, as in-vitro experiences have shown that adipocytes can stimulate cancer cell proliferation. This study analysed the records of patients who had AFT after breast cancer from 2004–2009. The primary end-point was cancer recurrence. The secondary end-points were AFT complications and post-AFT mammogram modifications. Sixty-four patients (100 AFT) were included. The mean follow-up for AFT was 46.44 months (SD = 21.4). Two breast cancer recurrences were recorded (3.1%). Among 55 mammograms analysed, only one patient presented radiological abnormalities. One complication of AFT (donor-site infection) was recorded. This series is in favour of the oncological safety of AFT after breast cancer. An accurate evaluation of the recurrence risk, before performing AFT, is an essential prerequisite and must lead one to postpone or avoid this procedure in high-risk patients.

4-Year Outcome Analysis of Endoscopic Vein Harvesting for Coronary Artery Bypass Grafting

Objective. Despite increasing recognition that endoscopic vein harvesting (EVH) is associated with decreased leg wound morbidity, improved cosmetic results, and enhanced patient satisfaction, concerns persist regarding the safety and efficacy of EVH. This study compares in-hospital and midterm outcomes for EVH and open vein harvesting (OVH) at our institution. Methods. 772 patients with EVH were propensity matched to 772 patients who had OVH. Their data were prospectively entered into the cardiac surgery database (PATS; Dendrite Clinical Systems, Ltd., Oxford, UK) and analyzed, retrospectively. The mean duration of followup was 26.4 ± 10.3 months. Results. EVH was associated with a significant reduction in rate of donor site infection compared to OVH (0.39% versus 3.9%, ). Short- and medium-term vein graft patency was similar. After adjusting for clinical covariates, EVH did not emerge as an independent predictor of readmission to hospital for cardiac causes (odds ratio (OR) 1.19, 95% confidence interval (CI) 0.96–1.58, and ), medium-term mortality (hazard ratio (HR) 1.28, 95% CI 1.09–1.42, and ), and need for reintervention (HR 1.21, 95% CI 0.98–1.32, and ). Risk-adjusted survival was 94% for EVH patients and 93% for OVH patients () during the medium-term followup. Conclusion. Our analysis confirms the short- and midium-term safety and efficacy of EVH.

SPINE SURGERY;

Objectives: The objective of this study is to find out the complication directly related to iliac bone graft harvest in spinesurgery. Design: Observational prospective study. Setting: Department of Orthopedic and Spine surgery, Hayatabad Medical ComplexPeshawar. Period: January 2007 to April 2012 on 139 patients. Material and method: Only those cases were included in whom bonegrafting was done for fusion as part of their spine surgery and were successfully followed for at least 6 months. Results: Out of 139patients 59(42.4%) were female patients while 80(57.6%) were male. Minimum age of the patients was 4 years while maximum was 70years. In 119(85.6%) patients cortico-cancellous bone graft was taken. While in 20(14.4%) patients, tri-cortical graft was taken. Inmajority 106(76.3%) cases graft was obtained from the posterior iliac crest while in 33(23.7%) it was obtained from the anterior iliaccrest. 45(32.4%) had some pain at the bone graft site. 8(5.8%) had early deep infection while 6(4.3%) had early superficial infection. Nine(6.4%) of our patients had nerve injury evident by parasthesia in the zone of distribution. Conclusions: Iliac crest is an excellent sourceand best available material for autogenous bone grafting. However it is not free of complications. The most common complications arepersistent chronic donor site pain, infection and heamatoma.

Use of bone graft substitutes in the management of tibial plateau fractures

The current available evidence for the use of bone graft substitutes in the management of subchondral bone defects associated with tibial plateau fractures as to their efficiency and safety has been collected following a literature review of the Ovid MEDLINE (1948–Present) and EMBASE (1980–Present).Nineteen studies were analysed reporting on 672 patients (674 fractures), with a mean age of 50.35 years (range 15–89), and a gender ratio of 3/2 males/females. The graft substitutes evaluated in the included studies were calcium phosphate cement, hydroxyapatite granules, calcium sulphate, bioactive glass, tricalcium phosphate, demineralised bone matrix, allografts, and xenograft.Fracture healing was uneventful in over 90% of the cases over a variant period of time. Besides two studies reporting on injectable calcium phosphate cement excellent incorporation was reported within 6 to 36 months post-surgery. No correlation was made by any of the authors between poor incorporation/resorption and adverse functional or radiological outcome. Secondary collapse of the knee joint surface ≥2 mm was reported in 8.6% in the biological substitutes (allograft, DBM, and xenograft), 5.4% in the hydroxyapatite, 3.7% in the calcium phosphate cement, and 11.1% in the calcium sulphate cases. The recorded incidence of primary surgical site and donor site infection (3.6%) was not statistically significant different, however donor site-related pain was reported up to 12 months following autologous iliac bone graft (AIBG) harvest. Shorter total operative time, greater tolerance of early weight bearing, improved early functional outcomes within the first year post-surgery was also recorded in the studies reporting on the use of injectable calcium phosphate cement (Norian SRS).Despite a lack of good quality randomised control trials, there is arguably sufficient evidence supporting the use of bone graft substitutes at the clinical setting of depressed plateau fractures.

New Clinical Classification System for Atlantoaxial Dislocation

The purpose of this study was to define a new clinical classification of atlantoaxial dislocation based on its clinical manifestations, namely reducible atlantoaxial dislocation (RAAD), irreducible atlantoaxial dislocation (IAAD), and fixed atlantoaxial dislocation (FAAD). A total of 107 patients with atlantoaxial dislocation were respectively treated based on this clinical classification, including 66 patients with RAAD, 39 patients with IAAD, and 2 patients with FAAD. Six of the 66 patients with RAAD with rotatory atlantoaxial dislocation were treated with traction and a cervical collar, 9 with fresh type II dens fracture were treated with cannulated screw fixation, and 51 were treated with posterior atlantoaxial or occipitocervical arthrodesis. Thirty-eight patients with IAAD received a transoral atlantoaxial reduction plate system, and 1 with a giant cell tumor was treated with lesion resection and vertebral reconstruction by a shaped titanium mesh system followed by posterior occipitocervical screw-rod fixation. The 2 patients with FAAD underwent anterior decompression and received a transoral atlantoaxial reduction plate system. Follow-up data were obtained for a minimum of 6 months. All patients' neurological symptoms improved postoperatively. Bony union was accomplished by 3-month follow-up. Donor-site infection was found in 1 patient, with no occurrence of other complications. This article proposes a new classification of atlantoaxial dislocation indicating the severity and difficulty in reduction of the atlantoaxial joint. The classification system assists with decision making regarding therapeutic options. Transoral atlantoaxial reduction plate fixation and posterior atlantoaxial screw-rod fixation are commonly performed for atlantoaxial dislocation.

Human amniotic fluid stem cell injection therapy for urethral sphincter regeneration in an animal model

BackgroundStem cell injection therapies have been proposed to overcome the limited efficacy and adverse reactions of bulking agents. However, most have significant limitations, including painful procurement, requirement for anesthesia, donor site infection and a frequently low cell yield. Recently, human amniotic fluid stem cells (hAFSCs) have been proposed as an ideal cell therapy source. In this study, we investigated whether periurethral injection of hAFSCs can restore urethral sphincter competency in a mouse model.MethodsAmniotic fluids were collected and harvested cells were analyzed for stem cell characteristics and in vitro myogenic differentiation potency. Mice underwent bilateral pudendal nerve transection to generate a stress urinary incontinence (SUI) model and received either periurethral injection of hAFSCs, periurethral injection of Plasma-Lyte (control group), or underwent a sham (normal control group).For in vivo cell tracking, cells were labeled with silica-coated magnetic nanoparticles containing rhodamine B isothiocyanate (MNPs@SiO2 (RITC)) and were injected into the urethral sphincter region (n = 9). Signals were detected by optical imaging. Leak point pressure and closing pressure were recorded serially after injection.Tumorigenicity of hAFSCs was evaluated by implanting hAFSCs into the subcapsular space of the kidney, followed two weeks later by retrieval and histologic analysis.ResultsFlow activated cell sorting showed that hAFSCs expressed mesenchymal stem cell (MSC) markers, but no hematopoietic stem cell markers. Induction of myogenic differentiation in the hAFSCs resulted in expression of PAX7 and MYOD at Day 3, and DYSTROPHIN at Day 7. The nanoparticle-labeled hAFSCs could be tracked in vivo with optical imaging for up to 10 days after injection. Four weeks after injection, the mean LPP and CP were significantly increased in the hAFSC-injected group compared with the control group. Nerve regeneration and neuromuscular junction formation of injected hAFSCs in vivo was confirmed with expression of neuronal markers and acetylcholine receptor. Injection of hAFSCs caused no in vivo host CD8 lymphocyte aggregation or tumor formation.ConclusionshAFSCs displayed MSC characteristics and could differentiate into cells of myogenic lineage. Periurethral injection of hAFSCs into an SUI animal model restored the urethral sphincter to apparently normal histology and function, in absence of immunogenicity and tumorigenicity.