Tranexamic Acid in Infantile Craniosynostosis Surgery: Friend or Foe?

BACKGROUND: Recent studies support the prophylactic use of tranexamic acid during craniosynostosis surgery to reduce blood loss. The study aims to assess national trends and outcomes of tranexamic acid administration. METHODS: The Pediatric Health Information System database was used to identify patients who underwent craniosynostosis surgery over a 9-year period (2010 to 2018). Search criteria included patients younger than 2 years with a primary diagnosis of craniosynostosis (International Classification of Diseases, Ninth Revision, 756.0; International Classification of Diseases, Tenth Revision, Q75.0) and CPT code for craniotomy (61550 to 61559). Tranexamic acid use, complications, length of stay, and transfusion requirements were recorded. Subgroup analysis was performed for fronto-orbital advancements and single-suture surgery. RESULTS: A total of 1345 patients were identified. Mean patient age was 229 ± 145 days. Four hundred fifty-four patients (33.7 percent) received tranexamic acid. Tranexamic acid use increased from 13.1 percent in 2010 to 75.6 percent in 2018 (p = 0.005), and mean blood products per patient increased from 1.09 U to 1.6 U (p = 0.009). Surgical complication rate was higher in those receiving tranexamic acid (16.7 percent versus 11.1 percent; p = 0.004). Tranexamic acid administration was associated with increased transfusion requirements on univariate and multivariate analysis (1.76 U versus 1.18 U; OR, 2.03; p < 0.001). In the fronto-orbital advancement subgroup, those receiving tranexamic acid received more total blood products (2.2 U versus 1.8 U; p = 0.02); this difference was present but not significant within the single-suture group (0.69 U versus 0.50 U; p = 0.06). CONCLUSIONS: Tranexamic acid use in craniosynostosis surgery has increased dramatically since 2010. However, it was associated with higher transfusion and complication rates in this data set. Optimization of its use and blood loss mitigation in infant craniosynostosis deserve continued research. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.

Surgical Treatment of Chronic Hand Ischemia: A Systematic Review and Case Series.

Background: Chronic hand ischemia refers to progressive, non-acute ischemic symptoms such as cold intolerance, rest pain, ulceration, tissue necrosis, and digit loss and poses a significant challenge in management. Conservative treatment begins with medical optimization and pharmacologic therapy, but when symptoms persist, surgical intervention may be required. Various operations exist to improve circulation including sympathectomy, arterial bypass, or venous arterialization. The purpose of this study is to systematically review published outcomes and present our experience with each surgical technique. Methods: A systematic review of literature regarding surgical treatment of chronic hand ischemia published between 1990 and 2016 was conducted using PRISMA guidelines. A retrospective-review of surgical interventions for chronic hand ischemia from 2010 to 2016 was then conducted. Primary outcomes included improvement in pain, wound-healing, and development of new ulcerations. Results: The review included 38 eight studies, showing all three techniques were effective in treating chronic hand ischemia. Sympathectomy had the lowest rate of new ulcerations (0.8%); bypass had the highest rate of healing existing ulcerations (89%). Arterialization was associated with consistent pain improvement pain (100%) but more complications (30.8%). Our series included 18 patients with 21 affected hands, 18 sympathectomies, 6 ulnar artery bypasses, and 1 arterialization. Most hands had improvement of wounds (89.5%) and pain (78.9%). No patients developed new ulcerations, but one required secondary amputation. Conclusions: When conservative measures fail to improve chronic hand ischemia, surgical intervention is an effective last line treatment. An algorithmic approach can determine the best operation for patients with chronic hand ischemia.

A Sustainable Model for Patient follow-up following an International Cleft Mission: A Proof of Concept.

PURPOSE: Patient follow-up after cleft missions is imperative if we are to critically assess the quality of care provided in these settings. The adoption of mobile telephones among disadvantaged families abroad may enable such an undertaking in a cost-effective manner. This project aimed to assess the efficacy of cellular phone-based follow-up in a developing country following a cleft mission to Thailand. METHODS: Changing Children's Lives Inc. performed a cleft surgical mission to Udon Thani, Thailand, in January 2013. Telephone numbers collected at that time were used to survey the patients or their parents 1.5 years postoperatively. RESULTS: Of the 56 patients who underwent cleft lip and/or palate surgery during the mission, more than 50% ( n = 30, 54%) were reachable by telephone; all chose to participate in the study. The cost for families was U.S. $124.92 (56.15); 26 families (87%) believed their money was well spent. Follow-up care was received by 22 (73%) patients, and all but one family ( n = 29, 97%) felt that their child received all of the medical care and support required. All families ( N = 30) would recommend similar cleft care to a friend. Of the patients younger than 18 years of age ( n = 24, 80%), 20 (80%) families found their child more comfortable interacting with peers, more comfortable interacting with adults, and more confident postoperatively. CONCLUSION: In one month, a survey response rate of more than 50% was obtained by leveraging the increased adoption of mobile phones in rural settings. Nearly all patients/families treated during the cleft mission were satisfied with the care that they received.

Cephalometric Improvement of Severe Microretrognathia With an Anterior Open Bite Using Curvilinear Mandibular Distraction Osteogenesis.

Curvilinear mandibular distraction osteogenesis (MDO) provides for multidimensional augmentation and rotation in mandibles with complex, abnormal morphology. This study aims to demonstrate cephalometric changes after curvilinear MDO.A prospectively maintained craniofacial database was queried for patients undergoing curvilinear MDO from 2009 to 2015. Demographic and operative data were collected. Cephalometric measurements were obtained from preoperative and postdistraction imaging, including sella-nasion-B point angle (SNB), mandibular plane angle (MPA), occlusal plane angle (OPA), and gonial angle (GA). Measurements were compared using a paired t test.Nine patients exhibiting microretrognathia and an anterior open-bite deformity had a mean age of 8.4 ±â€Š6.0 years and a mean follow-up of 23.2 ±â€Š25.3 months. Mean distance distracted was 32.6 ±â€Š7.2 mm, with augmentation in length and height, and rotatory closure of anterior open bites. Preoperative SNB versus postdistraction was 66.9 ±â€Š4.2 versus 78 ±â€Š9.1° (P = 0.0029). MPA, OPA, and GA all decreased (61.0 ±â€Š10.7 vs. 45.7 ±â€Š11.1°, P = 0.0066, 37.3 ±â€Š8.9 vs. 25.7 ±â€Š6.0°, P = 0.0025, 140.3 ±â€Š16.1 vs. 127.3 ±â€Š13.2°, P = 0.0019, MPA, OPA, and GA, respectively), trending toward normalization. Airway diameter increased by 7.1 ±â€Š2.8 mm. Anterior bite improved by 7.2 ±â€Š1.9 mm. Complications arose in 2 subjects including device malfunction and wound infection.Curvilinear MDO results in dramatic cephalometric improvement in patients with severe microretrognathia and anterior open-bite. The procedure is associated with a high rate of complications, and long-term stability of movement has yet to be documented.

Gelfoam Interposition Minimizes Risk of Fistula and Postoperative Bleeding in Modified-Furlow Palatoplasty.

Failure to accomplish a tension-free, watertight closure predisposes the palatoplasty patient to fistula formation. Perioperative bleeding also places the patient at risk for adverse airway events (AAE). This study introduces the incorporation of a hemostatic gelatin sponge (Gelfoam) into layered palatoplasty to minimize adverse postoperative bleeding and fistula formation. A retrospective chart review was performed to identify subjects who underwent Furlow palatoplasty with insertion of Gelfoam from 2010 to 2015. Exclusion criteria include age >3 years, prior palate surgery, <30-day follow-up, immunosuppressive state, and diagnosis of Treacher-Collins or Apert Syndrome. Demographic data include age, sex, cleft laterality, prior surgeries, Veau classification, Pierre Robin status, and tracheostomy dependence. Primary outcome was fistula formation. Secondary outcomes included perioperative metrics and AAE.One hundred subjects met criteria, 45% female. Average age was 14.6 months. Subjects with syndromes comprised 28%, with 16% diagnosed with Pierre Robin. Two subjects were tracheostomy-dependent. Prior cleft and mandibular procedures were performed in 55%. Isolated palatal defects were seen in 46%, unilateral lip and palate in 41%, and bilateral lip and palate in 13%. The majority of defects were Veau II and III (35% and 34%, respectively). Adverse airway events occurred in 2%, one of which resulted in reintubation. One subject (1%) was found to have a postoperative fistula.The incorporation of Gelfoam in the modified-Furlow palatoplasty results in a low rate of oronasal fistula (1%) and low perioperative risk of AAE. Further prospective comparison of this method to others will be the focus of future work.

Frontal Sinus Volume and Frontal Bar Position Are Associated in Unicoronal Craniosynostosis.

BACKGROUND: Frontal sinus pneumatization plays an important role in brow protrusion, and absence of frontal sinus development may be associated with brow retrusion. Using unicoronal craniosynostosis as a model, the authors studied the relationship among frontal sinus volume, supraorbital retrusion, and brow position. METHODS: The authors conducted a retrospective review of unicoronal craniosynostosis patients with head computed tomographic scans and photographs taken from ages 5 to 18 years. Frontal sinus volume and supraorbital retrusion were calculated using three-dimensional computed tomographic reconstructions. A "brow score" from 0 to 3 was assigned to each patient's photographs by a consensus of two craniofacial surgeons; sinus morphology and brow scores were compared. RESULTS: The study included 20 unicoronal craniosynostosis patients. The affected side demonstrated increased retrusion (7.1 ± 3.7 mm versus 3.0 ± 3.1 mm; p < 0.001) and decreased frontal sinus volume (0.8 ± 0.9 cc versus 2.6 ± 1.8 cc; p < 0.001). Qualitative brow retrusion scores differed between affected and unaffected sides (score of 0, 17 percent affected versus 78 percent unaffected; score of 1, 28 percent versus 22 percent; score of 2, 39 percent versus 0 percent; and score of 3, 17 percent versus 0 percent; p < 0.001). Brow scores trended with retrusion measurements (score of 0, 2.7 ± 2.9 mm retrusion; score of 1, 6.1 ± 3.5 mm; score of 2, 8.9 ± 3.2 mm; and score of 3, 9.7 ± 2.8 mm; p < 0.001). Subjects with brow scores of 0 or 1 had larger frontal sinus volumes than subjects with brow scores of 2 or 3 (p = 0.018). CONCLUSIONS: Qualitative brow retrusion correlates strongly with both quantitative supraorbital retrusion and frontal sinus volume. Although this retrospective study cannot prove causality, which is likely multifactorial, its strong correlation with frontal sinus pneumatization highlights the importance of the frontal sinus in brow position in unicoronal craniosynostosis. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.

Attitude of hand surgeons toward Affordable Care Act: A survey of members of American Society for Surgery of the Hand.

The purpose of this study was to examine current attitude of hand surgeons toward the Affordable Care Act (ACA). An electronic survey was sent to members of American Society for Surgery of the Hand (ASSH) to examine their attitude toward the Affordable Care Act. 974 ASSH members responded to the survey (33% response rate). The majority of respondents were male (89%), trained in orthopedic surgery (81%), and in private practice (75%). 41% of respondents rated their knowledge of the ACA as average. Respondents disagreed that the ACA would improve healthcare in the United States (median 2, mean 2.06, scale 1-5), while agreeing that the ACA would decrease reimbursements specific to hand surgery (median 4, mean 4.11).

Assessing Risk Factors for Hospital-Based, Acute Care Within Thirty Days of Craniosynostosis Surgery Using the Healthcare Cost and Utilization Project.

While in-hospital outcomes and long-term results of craniosynostosis surgery have been described, no large studies have reported on postoperative readmission and emergency department (ED) visits. The authors conducted this study to describe the incidence, associated diagnoses, and risk factors for these encounters within 30 days of craniosynostosis surgery.Using 4 state-level databases, the authors conducted a retrospective cohort study of patients <3 years of age who underwent surgery for craniosynostosis. The primary outcome was any hospital based, acute care (HBAC; ED visit or hospital readmission) within 30 days of discharge. Multivariate logistic regression modeling was used to identify factors associated with this outcome.The final sample included 1120 patients. On average, patients were ages 4.6 months with the majority being male (67.3%) and having Medicaid (52%) or private (48.0%) insurance. Ninety-nine patients (8.8%) had at least 1 HBAC encounter within 30 days and 13 patients (1.2%) had 2 or more. The majority of encounters were managed in the ED without hospital admission (56.6%). In univariate analysis, age, race, insurance status, and initial length of stay significantly differed between the HBAC and non-HBAC groups. In multivariate analysis, only African-American race (adjusted odds ratio [AOR] = 5.98 [1.49-23.94]) and Hispanic ethnicity (AOR = 5.31 [1.88-14.97]) were associated with more frequent HBAC encounters.Nearly 10% of patients with craniosynostosis require HBAC postoperatively with ED visits accounting for the majority of these encounters. Race is independently associated with HBAC, the cause of which is unknown and will be the focus of future research.

A Perioperative Risk Comparison of Posterior Vault Distraction Osteogenesis in an Older Pediatric Population.

There is a growing literature on the advantages of posterior cranial vault distraction osteogenesis (PVDO) in infants, particularly those with syndromic and multisuture craniosynostosis. This study aims to compare perioperative outcomes of PVDO in older patients to those of infants. A prospective craniofacial database was queried for patients aged 5 and older undergoing PVDO; controls were diagnosis-matched infants. Demographic, perioperative, and distraction data was compared using a 2-sample t test and Fisher exact test.Twenty patients met inclusion criteria, and all had syndromic craniosynostosis. Mean age was 9.2 years for the older group, and 0.7 years for the younger. Older children had less weight-based blood loss (mean 58.6 ±â€Š38.8 versus 14.6 ±â€Š7.0 cc/kg, control versus older, P = 0.0092) and weight-based transfusion (mean 70.1 ±â€Š37.2 versus 21.2 ±â€Š9.9 cc/kg, control versus older, P = 0.0023); other perioperative variables were similar including duration of surgery, length of stay, distance distracted, time in consolidation, and length of follow-up. All patients in both groups successfully completed PVDO, and all older patients had resolution of papilledema and/or headaches. One from each group developed a wound infection that was treated with oral antibiotics.Posterior cranial vault distraction osteogenesis is a safe and efficacious for cranial vault expansion in syndromic craniosynostosis, with similar perioperative outcomes in older children as compared to infants. Posterior cranial vault distraction osteogenesis may be a reasonable alternative in older syndromic patients with acceptable frontal morphology and concerns for increased intracranial pressure.

Impact of Fronto-Orbital Advancement on Frontal Sinus Volume, Morphology, and Disease in Nonsyndromic Craniosynostosis.

BACKGROUND: Fronto-orbital advancement for nonsyndromic craniosynostosis has been thought to injure frontal sinus buds, lead to chronic sinus disease, and influence final forehead shape. This study investigates the effect of fronto-orbital advancement in infancy on subsequent frontal sinus volume, morphology, and disease. METHODS: The authors conducted a retrospective review of nonsyndromic craniosynostosis patients treated with fronto-orbital advancement in infancy with a head computed tomographic scan obtained at age 7 to 18 years. Facial trauma patients served as age-matched controls. Frontal sinus characteristics were determined using three-dimensional reconstructions. RESULTS: The study included 33 nonsyndromic craniosynostosis patients who underwent fronto-orbital advancement (n = 20 unicoronal; n = 13 metopic) and 20 control patients. The incidence of at least unilateral pneumatization was 94 percent for fronto-orbital advancement subjects and 95 percent for control subjects. Mean frontal sinus volumes for unicoronal synostosis, metopic synostosis, and control groups were 3427 ± 2294, 4576 ± 3510, and 4157 ± 3963 mm, respectively (p = 0.598). Asymmetry scores were as follows: unicoronal synostosis, 56 ± 35 percent; metopic synostosis, 36 ± 33 percent; and control, 23 ± 24 percent (p = 0.010). Unicoronal subjects displayed prominent asymmetry, with increased pneumatization on the unaffected side. Frontal sinus volume correlated with age at computed tomography but not with age at fronto-orbital advancement. Interrater reliability was 0.997. One fronto-orbital advancement subject and zero control subjects demonstrated computed tomographic evidence of frontal sinus disease. CONCLUSIONS: Frontal sinus volume, morphology, and disease do not differ significantly between control subjects and nonsyndromic craniosynostosis subjects following fronto-orbital advancement, but subtle differences such as increased asymmetry in the unicoronal synostosis group can be appreciated. Further research with syndromic craniosynostosis patients undergoing multiple procedures may help elucidate the association between surgical disruption and frontal sinus development. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.

An Algorithmic Approach to the Surgical Treatment of Chronic Ischemia of the Hand: A Systematic Review of the Literature.

BACKGROUND: Chronic ischemia of the hand can lead to intractable pain, cold intolerance, and digital necrosis, affecting up to 4.8 percent of patients undergoing vascular surgery. Treatment of patients suffering from chronic hand ischemia, in particular, the subset of patients with a nonreconstructible distal arterial tree, can be a significant challenge for hand surgeons. The purpose of this systematic review is to analyze the outcomes of surgical therapies in an effort to define the efficacy of each intervention. The authors also revisit the treatment algorithm for nontraumatic chronic hand ischemia. METHODS: A systematic search of the literature published since 1990 in the PubMed/MEDLINE database was performed using keywords. Articles were eligible if they described clinical studies of human patients with nontraumatic chronic hand ischemia who underwent sympathectomy, arterial bypass, or venous arterialization. Pain improvement, wound healing, and new ulcerations were primary outcome measures. Primary patency rates and limb salvage data were also collected as primary outcome measures in the bypass and arterialization study arms. RESULTS: For sympathectomy, arterial bypass, and venous arterialization, pain relief was achieved in 89, 100, and 100 percent of patients, respectively; whereas wound healing occurred in 74, 93, and 75 percent, respectively. Postoperative ulcerations were 0, 3, and 8 percent, respectively. No secondary amputations were reported in these 33 studies. Complication rates were moderately high (2.1 to 30.8 percent). CONCLUSION: This systematic review confirms that sympathectomy, arterial bypass, and venous arterialization are efficacious treatments, and allows for an algorithmic approach to the surgical treatment of chronic hand ischemia. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

Lymph node content of supraclavicular and thoracodorsal-based axillary flaps for vascularized lymph node transfer.

OBJECTIVE: Microvascular transfer of lymph node flaps has recently gained popularity as a treatment for secondary lymphedema often occurring after axillary, groin, or pelvic lymph node dissections. This study aimed to delineate the lymph node contents and pedicle characteristics of the supraclavicular (SC) and thoracodorsal (TD)-based axillary flaps as well as to compare lymph node quantification of surgeon vs pathologist. METHODS: SC and TD flaps were dissected from fresh female cadavers. The surgeon assessed pedicle characteristics, lymph node content, and anatomy. A pathologist assessed all flaps for gross and microscopic lymph node contents. The κ statistic was used to compare surgeon and pathologist. RESULTS: Ten SC flaps and 10 TD flaps were harvested and quantified. In comparing the SC and TD flaps, there were no statistical differences between artery diameter (3.1 vs 3.2 mm; P = .75) and vein diameter (2.8 vs 3.5 mm; P = .24). The TD flap did have a significantly longer pedicle than the SC flap (4.2 vs 3.2 cm; P = .03). The TD flap was found to be significantly heavier than the SC flap (17.0 ± 4.8 vs 12.9 ± 3.3 g; P = .04). Gross lymph node quantity was similar in the SC and TD flaps (2.5 ± 1.7 vs 1.8 ± 1.2; P = .33). There was good agreement between the surgeon and pathologist in detecting gross lymph nodes in the flaps (SC κ = 0.87, TD κ = 0.61). CONCLUSIONS: The SC and TD flaps have similar lymph node quantity, but the SC flap has higher lymphatic density. A surgeon's estimation of lymph node quantity is reliable and has been verified in this study by comparison to a pathologist's examination.

Feasibility of the internal mammary lymph node flap as a vascularized lymph node transfer: A cadaveric dissection study.

BACKGROUND: We performed cadaveric dissections to examine the feasibility of an internal mammary-based lymph node flap as a donor site for vascularized lymph node transfer. METHODS: Internal mammary vessels and adjacent nodes were dissected in ten fresh cadaver specimens. Surgeon inspection and palpation identified the number of nodes in the specimen. Specimens were examined macro- and microscopically by a pathologist for correlation of lymph node counts. Kappa statistic correlated surgeon- and pathologist-reported node counts. RESULTS: Surgeon- and pathologist-reported node counts were moderately correlated (kappa 0.57). Inspection and palpation correctly predicted node presence or absence in 80% of specimens. Sixty percent of flaps contained between 1 and 3 nodes, with a mean of 2.0 nodes when nodes were present. CONCLUSIONS: Inspection and palpation predicts the presence or absence of nodes in 80% of flaps. Nodes were present in 60% of internal mammary-based flaps, and one to three nodes can be transferred. © 2015 Wiley Periodicals, Inc. Microsurgery 36:485-490, 2016.

An analysis of early oncologic head and neck free flap reoperations from the 2005-2012 ACS-NSQIP dataset.

BACKGROUND: There are limited population-based studies that examine perioperative factors that influence postoperative surgical take-backs to the OR following free flap (FF) reconstruction for head/neck cancer extirpation. The purpose of this study was to critically analyse head/neck free flaps (HNFF) captured in the ACS-NSQIP dataset with a specific focus on postoperative complications and the incidence of factors associated with re-operation. METHODS: The 2005-2012 ACS-NSQIP datasets were accessed to identify patients undergoing FF reconstruction after a diagnosis of head/neck cancer. Patient demographics, comorbidities, and perioperative risk factors were examined as covariates, and the primary outcome was return to OR within 30 days of surgery. A multivariate regression was performed to determine independent preoperative factors associated with this complication. RESULTS: In total, 855 patients underwent FF for head/neck reconstruction most commonly for the Tongue (24.7%) and Mouth/Floor/cavity (25.0%). Of these, 153 patients (17.9%) returned to the OR within 30 days of surgery. Patients in this cohort had higher rates of wound infections and dehiscence (p < 0.01). Medical complications were significantly higher and included pneumonia (12.4% vs 5.0%, p < 0.01), prolonged ventilation (16.3% vs 4.8%, p < 0.01), myocardial infarction (2.6% vs 0.6%, p = 0.017), and sepsis (7.2% vs 3.4%, p = 0.033). Regression analysis demonstrated that visceral flaps (OR = 9.7, p = 0.012) and hypoalbuminemia (OR = 2.4, p = 0.009) were significant predictors of a return to the OR. CONCLUSION: Based on data from the nationwide NSQIP dataset, up to 17% of HNFF return to the OR within 30 days. Although this data-set has some significant limitations, these results can cautiously help to improve preoperative patient optimisation and surgical decision-making.

A Systematic Review and Head-to-Head Meta-Analysis of Outcomes following Direct-to-Implant versus Conventional Two-Stage Implant Reconstruction.

BACKGROUND: Innovative approaches to reconstruction have ushered in an era of breast reconstruction in which direct-to-implant procedures can provide an immediately reconstructed breast. Balancing the benefits against its technical challenges is vital. The authors evaluated the safety and efficacy of using direct-to-implant versus conventional two-stage reconstruction through a systematic meta-analysis. METHODS: A literature search identified all articles published after 1999 involving prosthetic-based breast reconstruction as a two-stage tissue expander/implant or direct-to-implant technique. The primary outcomes of interest, including implant loss, capsular contracture, reoperation, and infection, were analyzed by means of head-to-head meta-analysis. RESULTS: Thirteen studies involving 5216 breast reconstructions were included. The average patient age was 47.2 ± 1.0 years, the average body mass index was 24.9 ± 0.8 mg/k2, and the average follow-up was 40.8 months. Wound infection, seroma, and capsular contracture risk were similar between groups. However, direct-to-implant reconstruction was associated with a higher risk for skin flap necrosis (OR, 1.43; p = 0.01; I2 = 51 percent) and reoperation (OR, 1.25; p = 0.04; I2 = 43 percent). Ultimately, the risk for implant loss was nearly two-fold higher with direct-to-implant reconstruction compared with tissue expander/implant reconstruction (OR, 1.87; p = 0.04; I2 = 33 percent). CONCLUSIONS: Although direct-to-implant and two-stage tissue expander/implant reconstruction are successful approaches, this meta-analysis demonstrates significantly greater risk of flap necrosis and implant failure with direct-to-implant reconstruction. The authors' findings suggest that the critical component of patient selection is judgment of mastectomy flap tissue quality. These findings can enhance the risk counseling process and highlight the need for additional investigations to optimize outcomes.

Operative Management of Nonsyndromic Sagittal Synostosis: A Head-to-Head Meta-analysis of Outcomes Comparing 3 Techniques.

BACKGROUND: The timing and surgical technique for the treatment of sagittal synostosis remain controversial. Calvarial vault remodeling (CVR), strip craniectomy (SC), and spring-mediated cranioplasty (SMC) are currently in use. We perform a meta-analysis of the literature to compare these 3 techniques. METHODS: A literature search identified articles involving operative management of nonsyndromic sagittal synostosis. Comparison of 2 operative techniques was required, and methodology was assessed via the American Society of Plastic Surgeons' Levels of Evidence. Three techniques were considered: CVR, SC, and SMC. Meta-analysis was conducted for change in cephalic index (CI), reported as weighted mean difference (WMD). Pooled subgroup comparisons were performed for operative time, length of stay, blood loss, and cost. RESULTS: Twelve studies providing level 2 or 3 evidence were included. All studies involved CVR (n = 187), 8 involved SC (n = 299), and 7 involved SMC (n = 158). Head-to-head comparison of change in CI demonstrated a greater, yet statistically insignificant change for CVR versus SMC, WMD = 0.94 (-0.23 to 2.11) (P = 0.12, I(2) = 55%). Calvarial vault remodeling showed a statistically greater change in CI versus SC, WMD = 1.47 (0.47-2.48) (P = 0.004, I(2) = 66%). Compared with SMC/SC, CVR had longer operative length (170 vs 97 minutes), higher blood loss (238 vs 47 mL), longer length of stay (5.1 vs 2.9 days), and higher costs ($35,280 vs $13,147), all with P < 0.0001. CONCLUSIONS: This study, the first meta-analysis comparing 3 primary operations for correcting nonsyndromic sagittal synostosis, demonstrates no difference in CI for CVR versus SMC and a small but statistically greater improvement in CI favoring CVR over SC. Secondary outcomes favored SC/SMC procedures over CVR. However, long-term studies are still needed to adequately assess the risk-benefit ratios.

Treatment of large calvarial defects with bone transport osteogenesis: a preclinical sheep model.

BACKGROUND: Bone transport osteogenesis (BTO), distraction of a free portion of bone across a defect, offers an autologous solution to large cranial defects that may allow treatment without permanent hardware implantation. This study establishes a sheep model to evaluate the feasibility and distraction kinetics of BTO. METHODS: Subtotal cranial defects (3.5 × 3.5 cm) were created in 10 young adult sheep and a transport segment (3.5 × 2 cm) traversed the defect at varying distraction rates (0, 0.5, 1.0, and 1.5 mm/day) using semi-buried cranial distractors. After a 6-week consolidation period, sheep were euthanized and the resultant bone was analyzed by CT, histology, and mechanical testing. RESULTS: Gross examination, histology, and 3D CT revealed that control animals had fibrous nonunion whereas distraction animals had ossified defects with fibrous nonunion at the distal docking site. There was one premature consolidation in the 0.5 mm/day group. The volume of bony regenerate in the 0.5, 1.0, and 1.5 mm/day distraction rate groups was statistically indistinct (P = 0.16). The mean flexural moduli (MPa) of non-decalcified samples from the control cranium, transport segment, and bone regenerate were found to be 4.50 ± 4.9, 6.17 ± 2.1, and 4.14 ± 4.8, respectively (P = 0.24). CONCLUSIONS: This experiment provides proof of concept for BTO for large calvarial defects in a sheep model. Distraction at a rate of 0.5 mm per day may place individuals at higher risk for premature consolidation, but distraction rates did not have significant effects on regenerate quantity or quality. Future work will include the use of curvilinear distraction devices for 3-dimensional contour.

Sustained delivery of rhBMP-2 by means of poly(lactic-co-glycolic acid) microspheres: cranial bone regeneration without heterotopic ossification or craniosynostosis.

BACKGROUND: Commercially available recombinant human bone morphogenetic protein 2 (rhBMP2) has demonstrated efficacy in bone regeneration, but not without significant side effects. The authors used rhBMP2 encapsulated in poly(lactic-co-glycolic acid) (PLGA) microspheres placed in a rabbit cranial defect model to test whether low-dose, sustained delivery can effectively induce bone regeneration. METHODS: The rhBMP2 was encapsulated in 15% PLGA using a double-emulsion, solvent extraction/evaporation technique, and its release kinetics and bioactivity were tested. Two critical-size defects (10 mm) were created in the calvaria of New Zealand white rabbits (5 to 7 months of age, male and female) and filled with a collagen scaffold containing either (1) no implant, (2) collagen scaffold only, (3) PLGA-rhBMP2 (0.1 µg per implant), or (4) free rhBMP2 (0.1 µg per implant). After 6 weeks, the rabbits were killed and defects were analyzed by micro-computed tomography, histology, and finite element analysis. RESULTS: The rhBMP2 delivered by means of bioactive PLGA microspheres resulted in higher volumes and surface area coverage of new bone than an equal dose of free rhBMP2 by micro-computed tomography (p=0.025 and p=0.025). Finite element analysis indicated that the mechanical competence using the regional elastic modulus did not differ with rhBMP2 exposure (p=0.70). PLGA-rhBMP2 did not demonstrate heterotopic ossification, craniosynostosis, or seroma formation. CONCLUSIONS: Sustained delivery by means of PLGA microspheres can significantly reduce the rhBMP2 dose required for de novo bone formation. Optimization of the delivery system may be a key to reducing the risk for recently reported rhBMP2-related adverse effects.