Assessing Alignment Using GAP Score and Complications for Pedicle Subtraction Osteotomy Revision Surgeries for Sagittal Deformity in Previously Fused Spines Using a Satellite Rod Technique.

OBJECTIVE: Pedicle subtraction osteotomy (PSO) is a surgical technique to restore lumbar lordosis in patients with rigid sagittal deformity. Herein, we report on outcomes of a surgical technique utilizing a 4-rod PSO with satellite rods. METHODS: A retrospective study was performed for a cohort of patients who underwent 4-rod PSO revision surgery for sagittal deformity. Procedures were performed by one surgeon at 2 different academic centers between 2004-2018. Alignment outcomes and complications specifically for revision surgeries in previously fused spines were assessed. RESULTS: 40 patients underwent PSO with the satellite rod technique (n = 29 at L3, 72.5%; n = 7 at L4, 17.5%). Mean PSO angle was 28.7 ± 7.6°. Two patients (5%) had rod fracture necessitating revision surgery at 32 and 34 months. Three patients (7.5%) developed proximal junctional kyphosis (PJK), but none required revision. No patients developed pseudoarthrosis. Mean preoperative sagittal vertical axis (SVA) was 13.5 ± 7.3 cm, which decreased to 4.8 ± 7.3 cm (P = 0.002) postoperatively. Mean preoperative pelvic incidence-lumbar lordosis (PI-LL) mismatch improved from 35.9 ± 16.6° preoperatively to 11.8 ± 14.6° postoperatively (P < 0.001). Mean preoperative pelvic tilt (PT) improved from 34.7 ± 9.8° preoperatively to 30.1 ± 9.0° (P = 0.026) postoperatively. Mean global alignment and proportion (GAP) score improved from 10 ± 2 preoperatively to 8 ± 2 postoperatively (P < 0.001), which was still considered severely disproportioned. CONCLUSIONS: Rod failure rate after PSO with the 4-rod satellite configuration was low. SVA, PI-LL mismatch, and PT significantly improved for these previously-fused patients. Mean GAP score also improved, but was still considered severely disproportioned, likely due to the inability of PSO to correct low LL or PT in previously-fused spines.

Upper Instrumented Vertebrae, Number of Levels Fused, and Plate Morphology Do Not Affect Severity of Chronic Dysphagia After Anterior Cervical Spine Surgery.

BACKGROUND: Disordered swallowing, or dysphagia, is the most common complication after anterior cervical spine (ACS) surgery. Many operative factors are associated with development of dysphagia. The aim of this study was to explore how number of levels instrumented, specific levels fused, and plate morphology affect chronic dysphagia after ACS surgery. METHODS: Consecutive patients referred to a tertiary center for otolaryngology evaluation for chronic dysphagia after ACS surgery between 2012 and 2017 were enrolled. Basic demographic data were obtained. Plain radiographs were reviewed for number of levels fused, upper instrumented vertebrae, and plate morphology. Plate morphology was categorized as a closed, small window, large window, or no profile plate. The 10-item Eating Assessment Tool (EAT-10) was used to assess dysphagia severity. RESULTS: Of 171 patients referred for dysphagia, 126 met inclusion criteria; 54% were female, with a mean age of 63 years (range, 32-88 years). Mean EAT-10 score was 18.5 ± 10.1. Mean time from spine surgery to videofluoroscopic swallow study for dysphagia was 58.3 months. Mean number of levels fused was 2.2 ± 0.9. There were no significant differences in EAT-10 scores in single-level versus multilevel fusion (19.0 vs. 18.4, P = 0.76) as well as with regard to upper instrumented vertebrae or plate morphology. CONCLUSIONS: In this series of patients with chronic dysphagia following ACS surgery, the severity of dysphagia as measured by the EAT-10 was not affected by upper instrumented vertebrae, number of levels fused, or plate morphology.

Do Orthopedic Surgeons or Neurosurgeons Detect More Hip Disorders in Patients with Hip-Spine Syndrome? A Nationwide Database Study.

Background: Disorders of the hip and lumbar spine can create similar patterns of pain and dysfunction. It is unknown whether all surgeons, regardless of orthopedic or neurosurgery training, investigate and diagnose concurrent hip and spine pathology at the same rate. Methods: Data were retrieved from Taiwan's National Health Insurance Research Database (NHIRD). Enrolled patients were stratified into hip and spine surgery at the same admission (Both), hip surgery before spine surgery (HS), or spine surgery before hip surgery (SH). The SH group was further subdivided based on whether spine surgery was performed by an orthopedic surgeon (OS) or neurosurgeon (NS), and differences in preoperative radiographic examinations and diagnoses were collected and analyzed. Results: In total, 1824 patients received lumbar spine surgery within 1 year before or after hip replacement surgery. Of these, 103 patients had spine and hip surgery in the same admission (Both), 1290 patients had spine surgery before hip surgery (SH), and 431 patients had hip surgery before spine surgery (HS). In the SH group, patients were categorized into spine surgery by orthopedic surgeons (OS) (n = 679) or neurosurgeons (NS) (n = 522). In the SH group, orthopedic surgeons investigated hip pathology with X-rays more often (52.6% vs. 38.1%, p < 0.001) and diagnosed more cases of hip disease (43.6% vs. 28.9%, p < 0.001) than neurosurgeons. Conclusions: Of patients in Taiwan's NHIRD who had concurrent surgical degenerative hip and lumbar spine disorders who had spine surgery before hip surgery, orthopedic surgeons obtained hip images and made hip-related diagnoses more frequently than did neurosurgeons.

Comprehensive classification system for multirod constructs across three-column osteotomies: a reliability study.

OBJECTIVE: In this study, the authors' goal was to determine the intra- and interobserver reliability of a new classification system that allows the description of all possible constructs used across three-column osteotomies (3COs) in terms of rod configuration and density. METHODS: Thirty-five patients with multirod constructs (MRCs) across a 3CO were classified by two spinal surgery fellows according to the new system, and then were reclassified 2 weeks later. Constructs were classified as follows: the number of rods across the osteotomy site followed by a letter corresponding to the type of rod configuration: "M" is for a main rod configuration, defined as a single rod spanning the osteotomy. "L" is for linked rod configurations, defined as 2 rods directly connected to each other at the osteotomy site. "S" is for satellite rod configurations, which were defined as a short rod independent of the main rod with anchors above and below the 3CO. "A" is for accessory rods, defined as an additional rod across the 3CO attached to main rods but not attached to any anchors across the osteotomy site. "I" is for intercalary rod configurations, defined as a rod connecting 2 separate constructs across the 3CO, without the intercalary rod itself attached to any anchors across the osteotomy site. The intra- and interobserver reliability of this classification system was determined. RESULTS: A sample estimation for validation assuming two readers and 35 subjects results in a two-sided 95% confidence interval with a width of 0.19 and a kappa value of 0.8 (SD 0.3). The Fleiss kappa coefficient (κ) was used to calculate the degree of agreement between interrater and intraobserver reliability. The interrater kappa coefficient was 0.3, and the intrarater kappa coefficient was 0.63 (good reliability). This scenario represents a high degree of agreement despite a low kappa coefficient. Correct observations by both observers were 34 of 35 and 33 of 35 at both time points. Misclassification was related to difficulty in determining connectors versus anchors. CONCLUSIONS: MRCs across 3COs have variable rod configurations. Currently, no classification system or agreement on nomenclature exists to define the configuration of rods across 3COs. The authors present a new, comprehensive MRC classification system with good inter- and intraobserver reliability and a high degree of agreement that allows for a standardized description of MRCs across 3COs.

Transforaminal Interbody Impaction of Bone Graft to Treat Collapsed Nonhealed Vertebral Fractures with Endplate Destruction: A Report of Two Cases.

BACKGROUND: A collapsed nonhealed vertebral fracture with endplate destruction is a challenging injury to address, as there is no single definitive treatment. We present two cases using an innovative transforaminal grafting technique to treat these patients. Case Presentation. Case 1: a 72-year-old woman had nonunion of an L1 compression fracture with destruction of both endplates. T12/L1 and L1/L2 transforaminal debridement and impaction of bone graft were performed followed by posterior instrumentation. At three years follow-up, the fusion mass between T12/L1 and L1/L2 was solid and the patient had minimal pain. Case 2: a 62-year-old woman had nonunion of an L1 burst fracture with destruction of the lower endplate. Hemilaminectomy and transforaminal interbody impaction of bone graft was performed. At three years follow-up, the patient had no back pain and a solid fusion. In both cases, local kyphosis was corrected and fusion obtained. CONCLUSIONS: Collapsed nonhealed vertebral body fractures combined with endplate destruction can be successfully treated with a one-step posterior surgery consisting of transforaminal debridement and impaction of bone graft in combination with posterior pedicle instrumentation.

Global alignment and proportion (GAP) scores in an asymptomatic, nonoperative cohort: a divergence of age-adjusted and pelvic incidence-based alignment targets.

PURPOSE: To investigate GAP scores in an asymptomatic cohort of adults, including older adults with age-expected changes in spinal alignment. METHODS: One hundred and twenty asymptomatic volunteers underwent full-body radiographic scans. Demographics and sagittal radiographic parameters (pelvic incidence, sacral slope, L1-S1 lordosis, L4-S1 lordosis, and global tilt) were measured and GAP scores calculated ( www.gapcalculator.com ). Mann-Whitney U test compared groups. RESULTS: Eighty-five individuals (65 female, average age 48 ± 16 years, BMI 27 ± 6 kg/cm2) were analyzed. The median GAP score was that of a proportioned spine (0, range 0-10). 20% were moderately disproportioned and 6% were severely disproportioned. The mean relative pelvic version, relative lumbar lordosis (RLL), lumbar distribution index (LDI), and relative spinopelvic alignment were all considered aligned, although the mean RLL and LDI scores were both greater than 1. When categorized by age (< 60 years, ≥ 60 years), the median GAP score of the younger group was 0 (normal), while the median GAP score of the older cohort was 1 (normal) and different from the younger group (p < 0.001). CONCLUSION: Most patients in this asymptomatic, nonoperative cohort were normally proportioned. However, a large percentage of asymptomatic volunteers were moderately or severely disproportioned. Older patients had higher scores, indicating some disproportion. There was also a small number of severely sagittally misaligned and poorly proportioned, yet asymptomatic, volunteers. Further refinement of individualized targets is needed to determine the effect on mechanical complications and quality of life given the divergent recommendations of age-adjusted targets and GAP targets.

Fluoroscopic Swallowing Abnormalities in Dysphagic Patients Following Anterior Cervical Spine Surgery.

OBJECTIVES: To evaluate the precise objective fluoroscopic abnormalities in persons with dysphagia following anterior cervical spine surgery (ACSS). METHODS: 129 patients with dysphagia after ACSS were age and sex matched to 129 healthy controls. All individuals underwent videofluoroscopic swallow study (VFSS). VFSS parameters abstracted included upper esophageal sphincter (UES) opening, penetration aspiration scale (PAS), and pharyngeal constriction ratio (PCR). Other data collected included patient-reported outcome measures of voice and swallowing, number of levels fused, type of plate, vocal fold immobility, time from surgery to VFSS, and revision surgery status. RESULTS: The mean age of the entire cohort was 63 (SD ± 11) years. The mean number of levels fused was 2.2 (±0.9). 11.6% (15/129) were revision surgeries. The mean time from ACSS to VFSS was 58.3 months (±63.2). The majority of patients (72.9%) had anterior cervical discectomy and fusion (ACDF). For persons with dysphagia after ACSS, 7.8% (10/129) had endoscopic evidence of vocal fold immobility. The mean UES opening was 0.84 (±0.23) cm for patients after ACSS and 0.86 (±0.22) cm for controls (P > .0125). Mean PCR was 0.12 (±0.12) for persons after ACSS and 0.08 (±0.08) for controls, indicating significant post-surgical pharyngeal weakness (P < .0125). The median PAS was 1 (IQR 1) for persons after ACSS as well as for controls. For ACSS patients, PCR had a weak correlation with EAT-10 (P < .0125). CONCLUSION: Chronic swallowing dysfunction after ACSS appears to be secondary to pharyngeal weakness and not diminished UES opening, the presence of aspiration, vocal fold immobility, or ACSS instrumentation factors.Level of Evidence: 3b.

NADPH oxidases in bone and cartilage homeostasis and disease: A promising therapeutic target.

Reactive oxygen species (ROS) generated by the NADPH oxidase (Nox) enzymes are important short-range signaling molecules. They have been extensively studied in the physiology and pathophysiology of the cardiovascular system, where they have important roles in vascular inflammation, angiogenesis, hypertension, cardiac injury, stroke, and aging. Increasing evidence demonstrates that ROS and Nox enzymes also affect bone homeostasis and osteoporosis, and more recent studies implicate ROS and Nox enzymes in both inflammatory arthritis and osteoarthritis. Mechanistically, this connection may be through the effects of ROS on signal transduction. ROS affect both transforming growth factor-ß/Smad signaling, interleukin-1ß/nuclear factor-kappa B signaling, and the resulting changes in matrix metalloproteinase expression. The purpose of this review is to describe the role of Nox enzymes in the physiology and pathobiology of bone and joints and to highlight the potential of therapeutically targeting the Nox enzymes.

Full Endoscopic Lumbar Diskectomy for Lumbar Disk Herniation in the Presence of a Low-Lying Cord.

BACKGROUND: The distal extent of the spinal cord is most often at the level of the L1 or L2 vertebral body. In rare cases, a low-lying cord extends more distally. In this scenario, pathology that normally causes radiculopathy may cause myelopathy due to compression of the cord rather than nerve roots of the cauda equina. CASE DESCRIPTION: A 40-year-old man presented with progressive leg pain, sensory changes, hyperreflexia, and gait disturbance 1 month after a fall. The patient was myelopathic and had central L1/2 and L2/3 disk herniations. After unsuccessful unilateral laminotomy bilateral decompression, it was decided that an endoscopic diskectomy would be the best technique to remove the disk herniation without trauma to the cord or destabilizing the spine to require fusion. A percutaneous endoscopic lumbar diskectomy at L1/2 was performed under local anesthesia. The patient's leg pain, sensory changes, hyperreflexia, and gait disturbance resolved after surgery, and he was doing well at 6 months' follow-up. CONCLUSIONS: In patients with spina bifida occulta who present with myelopathy, lumbar disk herniation should be considered if the patient has a low-lying cord. This is the first report of percutaneous endoscopic lumbar diskectomy for lumbar disk herniation in the presence of a low-lying spinal cord. We have demonstrated that this approach can treat this condition effectively and safely.

Swallowing Characteristics in Zenker's-like Diverticulum After Anterior Cervical Spine Surgery.

OBJECTIVES: A Zenker's diverticulum (ZD) is a hypopharyngeal pulsion diverticula caused by dysfunction of the cricopharyngeus muscle with herniation of hypopharyngeal mucosa through Killian's dehiscence. Anterior cervical spine surgery (ACSS) can cause a Zenker's-like traction diverticulum (ZTD) with a similar presentation but different pathophysiology. The purpose of this investigation was to compare the fluoroscopic parameters and surgical outcomes of ZTD after ACSS to those of typical ZD. STUDY DESIGN: Case-control study. METHODS: The charts of patients undergoing a videofluoroscopic swallow study after ACSS between January 1, 2014, and January 1, 2018, were evaluated for evidence of ZTD. Patients with ZTD were age and gender matched to persons with ZD. Fluoroscopic parameters and patient-reported outcomes were compared between groups. RESULTS: Eleven patients with ZTD were identified. The mean pharyngeal constriction ratio (PCR) was significantly higher for persons with ZTD (0.87 [±0.07] vs. 0.17 [±0.08]; P < 0.05). Mean hyolaryngeal elevation was significantly less (2.5 [±0.9] cm vs. 3.5 [±0.7] cm) and mean diverticulum size significantly smaller (1.3 [±1.0] cm vs. 2.3 [±2.0] cm) for persons with ZTD (P < 0.05). Five ZTD patients had exposed hardware necessitating open approach for removal. CONCLUSION: We report the largest cohort of ZTD after ACSS. ZTD are smaller than traditional Zenker's and associated with more pharyngeal weakness, poorer laryngeal elevation, and worse treatment outcomes. Although these diverticula can be managed endoscopically, the high percentage of exposed cervical hardware necessitates a thorough preoperative assessment and frequent need for open management and pharyngeal repair. LEVEL OF EVIDENCE: 3b Laryngoscope, 130:1383-1387, 2020.

Acute Changes in NADPH Oxidase 4 in Early Post-Traumatic Osteoarthritis.

Knee injuries cause structural damage and acute inflammation that initiates the development of post-traumatic osteoarthritis (PTOA). NADPH oxidase 4 (Nox4), a member of a family of enzymes that generates reactive oxygen species (ROS), plays a pivotal role in normal development of the musculoskeletal system, but may increase ROS production to harmful levels after joint injury. The role of ROS in both normal joint homeostasis and injury is poorly understood, but inhibition of excessive ROS production by Nox4 after joint injury could be protective to the joint, decreasing oxidative stress, and initiation of PTOA. Knee injuries were simulated using inflammatory cytokines in cultured primary human chondrocytes and a non-invasive mouse model of PTOA in C57BL/6N and Nox4 knockout mice. There is an acute decrease in Nox4 activity within 24 h after injury in both systems, followed by a subsequent sustained low-level increase, a novel finding not seen in any other system. Inhibition of Nox4 activity by GKT137831 was protective against early structural changes after non-invasive knee injury in a mouse model. Nox4 knockout mice had significant differences in structural and mechanical properties of bone, providing further evidence for the role of Nox4 in development of joint tissues and biochemical response after joint injury. Nox4 plays a significant role in the acute phase after joint injury, and targeted inhibition of inflammation caused by Nox4 may be protective against early joint changes in the pathogenesis of PTOA. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:2429-2436, 2019.

Treatment, complications, and outcomes of metastatic disease of the spine: from Patchell to PROMIS.

Spinal metastases are common in patients with cancer. As cancer treatments improve and these patients live longer, the number who present with metastatic spine disease will increase. Treatment strategies for these patients continues to evolve. In particular, since the prospective randomized controlled study in 2005 by Patchell et al. showed increased survival with decompressive surgical treatment of spinal metastases, there is a growing body of literature focusing on surgical management and complications of surgery for this disease. Surgery is often one component of a multimodal treatment approach with chemotherapy and radiation, which makes it difficult to parse the benefits of each individual treatment in outcome studies. Additionally, there has been more recent emphasis placed on patient-reported outcomes (PRO) after treatment for metastatic spine disease. In this review, we summarize treatments of metastatic spinal disease, possible perioperative complications, and validated tools used to assess outcomes for these patients.

Headless Compression Screw Fixation of Vertical Medial Malleolus Fractures is Superior to Unicortical Screw Fixation.

This study is the first biomechanical research of headless compression screws for fixation of vertical shear fractures of the medial malleolus, a promising alternative that potentially offers several advantages for fixation. Vertical shear fractures were simulated by osteotomies in 20 synthetic distal tibiae. Models were randomly assigned to fixation with either 2 parallel cancellous screws or 2 parallel Acutrak 2 headless compression screws (Acumed). Specimens were subjected to offset axial loading to simulate supination-adduction loading and tracked using high-resolution video. The headless compression screw construct was significantly stiffer (P < .0001) (360 ± 131 N/mm) than the partially threaded cancellous screws (180 ± 48 N/mm) and demonstrated a significantly increased (P < .0001) mean load to clinical failure (719 ± 91 N vs 343 ± 83 N). When specimens were displaced to 6 mm and allowed to relax, the headless compression screw constructs demonstrated an elastic recoil and were reduced to the pretesting fragment alignment, whereas the parallel cancellous screw constructs remained displaced. Along with the headless design that may decrease soft tissue irritation, the increased stiffness and elastic recoil of the headless compression screw construct offers improved fixation of medial malleolus vertical shear fractures over the traditional methods.

Mini-Fragment Fixation Is Equivalent to Bicortical Screw Fixation for Horizontal Medial Malleolus Fractures.

Horizontal fractures of the medial malleolus occur through application of valgus or abduction force through the ankle that creates a tension failure of the medial malleolus. The authors hypothesize that mini-fragment T-plates may offer improved fixation, but the optimal fixation construct for these fractures remains unclear. Forty synthetic distal tibiae with identical osteotomies were randomized into 4 fixation constructs: (1) two parallel unicortical cancellous screws; (2) two parallel bicortical cortical screws; (3) a contoured mini-fragment T-plate with 2 unicortical screws in the fragment and 2 bicortical screws in the shaft; and (4) a contoured mini-fragment T-plate with 2 bicortical screws in the fragment and 2 unicortical screws in the shaft. Specimens were subjected to offset axial tension loading on a servohydraulic testing system and tracked using high-resolution video. Failure was defined as 2 mm of articular displacement. Analysis of variance followed by a Tukey-Kramer post hoc test was used to assess for differences between groups, with significance defined as P<.05. The mean stiffness (±SD) values of both mini-fragment T-plate constructs (239±83 N/mm and 190±37 N/mm) and the bicortical screw construct (240±17 N/mm) were not statistically different. The mean stiffness values of both mini-fragment T-plate constructs and the bicortical screw construct were higher than that of a parallel unicortical screw construct (102±20 N/mm). Contoured T-plate constructs provide stiffer initial fixation than a unicortical cancellous screw construct. The T-plate is biomechanically equivalent to a bicortical screw construct, but may be superior in capturing small fragments of bone. [Orthopedics. 2018; 41(3):e395-e399.].

Headless compression screw for horizontal medial malleolus fractures.

BACKGROUND: Horizontal medial malleolus fractures are caused by the application of rotational force through the ankle joint in several orientations. Multiple techniques are available for the fixation of medial malleolar fractures. METHODS: Horizontal medial malleolus osteotomies were performed in eighteen synthetic distal tibiae and randomized into two fixation groups: 1) two parallel unicortical cancellous screws or 2) two Acutrak 2 headless compression screws. Specimens were subjected to offset axial tension loading. Frontal plane interfragmentary motion was monitored. FINDINGS: The headless compression group (1699 (SD 947) N/mm) had significantly greater proximal-distal stiffness than the unicortical group (668 (SD 298) N/mm), (P = 0.012). Similarly, the headless compression group (604 (SD 148) N/mm) had significantly greater medial-lateral stiffness than the unicortical group (281 (SD 152) N/mm), (P < 0.001). The force at 2 mm of lateral displacement was significantly greater in the headless compression group (955 (SD 79) N) compared to the unicortical group (679 (SD 198) N), (P = 0.003). At 2 mm of distal displacement, the mean force was higher in the headless compression group (1037 (SD 122) N) compared to the unicortical group (729 (SD 229) N), but the difference was not significant (P = 0.131). INTERPRETATION: A headless compression screw construct was significantly stiffer in both the proximal-distal and medial-lateral directions, indicating greater resistance to both axial and shear loading. Additionally, they had significantly greater load at clinical failure based on lateral displacement. The low-profile design of the headless compression screw minimizes soft tissue irritation and reduces need for implant removal.

Injuries sustained in National Collegiate Athletic Association men's and women's basketball, 2009/2010-2014/2015.

BACKGROUND/AIM: Recent rule changes regarding the safety of basketball athletes necessitate up-to-date reports of injury incidence. This study describes the epidemiology of injuries in men's and women's National Collegiate Athletic Association (NCAA) basketball during the 2009/2010-2014/2015 seasons. METHODS: Basketball injury data originate from the 2009/2010-2014/2015 academic years from the NCAA Injury Surveillance Program (NCAA-ISP) from 78 men's and 74 women's NCAA basketball programmes which provided 176 and 181 team-seasons, respectively. A reportable injury occurred during organised practice or competition and required attention from an athletic trainer (AT) or physician. Injury rates, injury proportions and rate ratios (RRs) were calculated. All 95% CIs not containing 1.0 were considered statistically significant. RESULTS: A total of 2308 and 1631 injuries were reported in men's and women's basketball, respectively, for injury rates of 7.97 and 6.54/1000 athlete-exposures (AEs). The rate was higher in men than women (RR=1.22; 95% CI 1.15 to 1.30). Non-time-loss (NTL) injuries (resulting in participation restriction time under 24 hours) accounted for 64.8% and 53.6% of men's competition and practice injuries, respectively, and 53.9% and 51.3% of women's competition and practice injuries, respectively. Injuries to the lower extremity were the most common in competitions (men: 54.9%; women: 59.0%) and practices (men: 62.4%; women: 67.3%). The most common injury in men's and women's basketball was ankle sprain (17.9% and 16.6%, respectively). CONCLUSIONS: NTL injuries account for over half of all injuries in basketball. Most injuries were lower extremity injuries, specifically ankle sprains. While rule changes have been implemented to make basketball safer, continued research is needed to assess the effectiveness of these changes.

Stem Cells in Spinal Fusion.

STUDY DESIGN: Review of literature. OBJECTIVES: This review of literature investigates the application of mesenchymal stem cells (MSCs) in spinal fusion, highlights potential uses in the development of bone grafts, and discusses limitations based on both preclinical and clinical models. METHODS: A review of literature was conducted looking at current studies using stem cells for augmentation of spinal fusion in both animal and human models. RESULTS: Eleven preclinical studies were found that used various animal models. Average fusion rates across studies were 59.8% for autograft and 73.7% for stem cell-based grafts. Outcomes included manual palpation and stressing of the fusion, radiography, micro-computed tomography (µCT), and histological analysis. Fifteen clinical studies, 7 prospective and 8 retrospective, were found. Fusion rates ranged from 60% to 100%, averaging 87.1% in experimental groups and 87.2% in autograft control groups. CONCLUSIONS: It appears that there is minimal clinical difference between commercially available stem cells and bone marrow aspirates indicating that MSCs may be a good choice in a patient with poor marrow quality. Overcoming morbidity and limitations of autograft for spinal fusion, remains a significant problem for spinal surgeons and further studies are needed to determine the efficacy of stem cells in augmenting spinal fusion.

Minimally Invasive Lateral Approach for the Management of Adult Degenerative Scoliosis.

Minimally invasive lateral releases for the correction of lumbar scoliosis are becoming an increasingly common treatment alternative to posterior osteotomies or surgery via an open anterior approach. Minimally invasive approaches minimize blood loss and morbidity, which may be important in older patients who often have substantial comorbidities. Anterior column realignment allows lumbar lordosis to be restored via a minimally invasive lateral approach, which restores sagittal balance and is correlated with improvements in health-related quality of life. Surgeons should understand the development of, the indications for, the surgical technique for, and the complications and early clinical outcomes of the minimally invasive lateral approach to the spine.

Surgical Management of Multijoint Septic Arthritis due to Rat-Bite Fever in a Pediatric Patient: A Case Study.

In the United States, rat-bite fever is a rare systemic illness principally caused by Streptobacillus moniliformis, an organism found in the nasopharyngeal flora of rodents. Infection through direct exposure to rat excreta such as saliva, urine, or feces can lead to fever, rash, and an asymmetric migratory polyarthritis. As rodents are becoming more popular as pets, more pediatric cases are being documented. We report a pediatric case of delayed onset septic arthritis in the left wrist and right knee due to S. moniliformis from a rat bite. Previously reported pediatric case studies of suppurative arthritis due to S. moniliformis have only involved the hip. This case study demonstrates the importance of a thorough exposure history and consideration of zoonotic infections as a cause of septic arthritis in a pediatric patient that requires antibiotics and surgical intervention.