Gait signatures of endurance runners with low back pain: A case controlled cross sectional study.

BACKGROUND: Low back pain (LBP) is an understudied condition among runners, and it is unclear what biomechanical features could be targeted for gait retraining to mitigate pain. RESEARCH QUESTION: How do running biomechanics differ between healthy individuals and those with running-related LBP? METHODS: This was a case-controlled, comparative study design of community runners: running-related LBP (n=52) and healthy controls (n=52). All runners completed running history forms and performed a 3-dimensional gait analysis. Kinematic data were collected using a motion capture system and normalized to a gait cycle, while participants ran on a level grade at self-selected speed on an instrumented treadmill. Current running volume, temporal-spatial, kinetic and kinematic features were compared between groups. RESULTS: The LBP group had 39.5 % lower weekly distance and 15.4 % fewer were currently training for a race (all p<.05). Runners with LBP demonstrated lower cadence (166±10 step/min vs. 171±9 step/min; p=.05), greater center of gravity lateral displacement (1.4±0.5 cm vs. 1.2 ±.3 cm; p=.044) and greater stride width variability (1.3±0.4 cm versus 1.0 ± 0.04 cm; p=.008). Runners with LBP had a greater Vertical Average Loading Rate ([VALR] 67.7±22.2 bodyweights [BW]/s vs. 62.2±21.5 BW/s; p=.022), and higher joint moments (N*m/(kg*m)) at the knee in the sagittal plane (2.13±0.50 vs. 1.87±0.56; p <.001), frontal plane (1.44±0.39 vs. 1.29±0.29; p=.013), and at the hip in the frontal plane (2.04±0.51 vs. 1.84±0.41; p=.024). No differences were found between groups in the pelvis, hip, knee, and ankle joint excursions in any plane of motion during a typical gait cycle. SIGNIFICANCE: These collective motion signature may reflect challenges with control of motion and VALR in the presence of back pain. Cadence training to increase step rate, coupled with core/hip muscle activation, may be an important strategy to reduce motion variability, impact loading rate and pain symptoms while running.

Pilot Study on Therapeutic Horticulture for Chronic Low Back Pain: A Mixed Methods Study.

Background: Chronic low back pain (LBP) is common and associated with disability worldwide. Therapists trained in Therapeutic Horticulture (TH) use gardening activities and proximity to nature for therapy and rehabilitation. Patients seeking care for LBP would benefit physically and psychologically from participating in TH. Primary study objectives: The first aim of this study was to determine if and which patients who were receiving care for chronic LBP were interested in TH to help manage their pain. The second aim of the project was to quantify changes in LBP, functional tasks and anxiety upon completion of a TH session in patients with LBP. Methods/Design: This was a 2-part study with a mixed methods design: the cross-sectional survey Group and the pilot experimental Group. The Cross-sectional Survey component comprised a total of 170 patients; age 55.9±17.3 years; 58% women. The Pilot Experimental component comprised a total of 9 patients; age 48±14.7 years; 78% women. Participants Cross-sectional component: Patients receiving medical care for LBP with or without additional joint pain sites (n=170; age 55.9 ± 17.3 years; 58% women. Participants Pilot experimental component: A total of 9 patients (7 women); mean age 48 ± 14.7 years and mean duration of back pain 12.6 ± 8.1 years. Setting: Patients were receiving medical care at the University of Florida Health Comprehensive Spine Center in the United States, in the tertiary care health system. Intervention: 1-hour TH session that involved trained therapists using propagating and harvesting herbs planted at various heights in an outdoor setting for therapy and rehabilitation. Primary outcome measures: A therapeutic horticulture interest survey, PROMIS Pain Interference and Physical Function scores, functional tests (timed-get-up-and-go [TUG], spine range of motion), Roland Morris Disability Questionnaire (RMDQ), 11-point Numerical Pain Rating Scale (NRSpain), 10-item PROMIS Global Health Questionnaire, Tampa Scale of Kinesiophobia-11 and patient enjoyment. Results: Cross-sectional survey component: A total of 2% of patients had not previously heard of TH and 68% were interested in learning more about it. Patients who expressed interest in TH reported a higher level of agreement that TH could improve mood, improve muscle strength, lower stress level, increase movement and enable patients to perform self-care activities with less pain (all P < .001). PROMIS Pain Interference and Physical Function scores did not differ by interest in TH (P > .05). Pilot Experimental component: In the pilot session, 44% reported using pain medication to manage their low back pain and 66% believed gardening could provide pain relief. Improvements were observed in anxiety (55.3%; P =.017), spine flexion (31.4%; P =.003) and spine rotation to the left (26.7%; P =.005). All participants believed that gardening improved overall health and spine motion while reducing low back pain. All patients reported having gardening experience at home and none had TH experience. Conclusion: Patients presenting to an outpatient spine clinic may be receptive to trying TH in conjunction with or in place of conventional medicine to promote health and well-being. The pilot experimental group data suggested that acute TH is enjoyable and may confer the benefits of reducing anxiety and improving spine motion. Future larger studies could use different dose response approaches, explore different TH activity types and involve participants from different geographic locations while controlling for LBP history and psychological status.

Surgical time and outcomes of stemmed versus stemless total shoulder arthroplasty.

BACKGROUND: Stemless total shoulder arthroplasty (TSA) was approved for use in the United States in 2015, and there remains a paucity of data on its performance in this market. Decreased operative time without compromise of clinical outcomes is a theoretical advantage of stemless TSA, but no studies have evaluated this in a comparative study to date. Herein, the operative times and clinical outcomes of stemless vs. conventional stemmed TSA are investigated. METHODS: This is a retrospective cohort study, evaluating all consecutive TSAs performed by a single surgeon between 2015 and 2018. Data were collected from 59 patients who underwent TSA with conventional, stemmed humeral implants and 115 patients in whom a stemless humeral implant was used. Operative times and demographic data were collected retrospectively from the anesthesia record, and prospectively collected patient-reported outcome measures were collected from the Surgical Outcomes System database. For patient-reported outcome measure, visual analog scale, American Shoulder and Elbow Surgeons, and Single Assessment Numerical Evaluation scores were recorded serially until a minimum 2-year follow-up. RESULTS: The average operative time was 24 minutes less in the stemless cohort compared with the stemmed cohort (104 minutes vs. 128 minutes, P < .001). Cost analysis showed a decreased personnel cost of 15.9% that correlates to a 3.1% overall reduction in operating room-associated cost. Patient-reported outcome scores significantly improved postoperatively in both cohorts across all time points. There was no difference found in visual analog scale, American Shoulder and Elbow Surgeons, and Single Assessment Numerical Evaluation scores between the cohorts at the 2-year follow-up. CONCLUSIONS: Stemless TSA significantly reduces operative time with equivalent functional outcomes at a minimum 2-year follow-up.

Oral Administration of a Chemically Modified Curcumin, TRB-N0224, Reduced Inflammatory Cytokines and Cartilage Erosion in a Rabbit ACL Transection Injury Model.

OBJECTIVE: To evaluate the effects of TRB-N0224, a chemically modified curcumin (CMC) with zinc binding properties and improved pharmacokinetics, in a rabbit anterior cruciate ligament (ACL) transection injury-induced model of osteoarthritis (OA). DESIGN: Thirty-eight skeletally mature New Zealand white rabbits were studied in 4 groups: a sham with arthrotomy (n = 6), control with ACL transection (n = 6), and 2 treatment groups with ACL transection and administration of TRB-N0224 at low (25 mg/kg/day) (n = 13) and high (50 mg/kg/day) (n = 13) doses. After euthanization at 12 weeks, outcomes were measured by post-necropsy gross morphology, biomechanics, and cartilage and synovium histology. Rabbit blood ELISA quantified cytokine and matrix metalloproteinase (MMP) concentrations at 0, 4, 8, and 12 weeks. RESULTS: Both treatment doses had fewer distal femoral condyle erosive defects than the control; the low dose demonstrated a mean 78% decrease (P < 0.01). Histologically, the low- and high-dose treatment groups had fewer cartilage pathologic changes and less severe synovitis than the control. CMC alone did not have a major effect on the biomechanics of healthy cartilage or cartilage in the ACL transection model, as demonstrated in 5 of the 6 measured properties/regions (P < 0.05). ELISA results suggested that the key mediators of OA, (interleukin) IL-1ß, IL-6, TNFα (tumor necrosis factor-α), MMP-9, and MMP-13, had decreased concentrations with TRB-N0224 treatment at different time points between weeks 4 to 12 (P < 0.05). CONCLUSIONS: In the pathogenesis of OA, an imbalance exists between catabolic and anabolic mediators. These results suggest the potential of TRB-N0224 to modulate MMP and cytokine levels, slowing the macroscopic and histopathological progression of OA.

Changing trends in the management of proximal humerus fractures in New York State.

PURPOSE: Reverse shoulder arthroplasty (RSA) as an alternative to hemiarthroplasty (HA) as treatment for proximal humerus fractures has prompted a re-evaluation of utilization trends. METHODS: Operative treatment for proximal humeral fractures were analyzed using a New York State database. RESULTS: After introduction as an ICD-9 code, RSA increased to 39.3% (m = +5.2%/year, r = 0.984). When stratifying by age ≥65, HA decreased to 7.7% (m = -2.8%/year, r = 0.962) while RSA increased to 50.6% (m = +6.4%/year, r = 0.985). CONCLUSION: RSA overtook HA as the arthroplasty procedure of choice for proximal humerus fractures. In patients ≥65, RSA passed ORIF as the most prevalent procedure in 2017. LEVEL OF EVIDENCE: III, Descriptive Epidemiology Study, Large Database Analysis.

Biomechanical and geometric characterization of peroneus longus allografts with respect to age.

BACKGROUND: Anterior cruciate ligament injuries are among the most common injuries in high impact sports, and reconstruction is the standard surgical procedure for these ruptures. Reconstructions are often performed using allografts rather than autografts on a case-by-case basis. Controversy exists as to whether or not age of donor tissue plays a factor in the mechanical properties of allografts. METHODS: 38 peroneus longus (PL) tendons were prepared using the two-strand graft technique and then subjected to a cyclic loading test regimen of 1000 cycles to determine material properties. Specimens were grouped based on age to ascertain whether donor age affects the material properties of PL tendons. FINDINGS: Secant modulus of the first cycle was determined to be 150.43 (SD 40.24) MPa. The average magnitude of the dynamic modulus was determined to be 82.81 (SD 24.65) MPa. Specimens were grouped into three distinct groups for analysis (x < 40 yo, 40 yo ≤ x < 60 yo, 60 yo < x). INTERPRETATION: The need for using intrinsic material properties is highlighted. There is no significant difference in any intrinsic material property with respect to age or the fatigue of the tendon as the cycle count increases. Conversely, the measured stiffness of a tendon decreased as function of age with a large effect size. Based on analysis of graft geometries, it was determined that PL tendons become significantly more slender with increased age which result in the observed decrease in stiffness.

Cadaveric Study of the Safety and Device Functionality of Magnetically Controlled Growing Rods After Exposure to Magnetic Resonance Imaging.

STUDY DESIGN: Cadaveric study. OBJECTIVE: To establish the safety and efficacy of magnetically controlled growing rods (MCGRs) after magnetic resonance imaging (MRI) exposure. SUMMARY OF BACKGROUND DATA: MCGRs are new and promising devices for the treatment of early-onset scoliosis (EOS). A significant percentage of EOS patients have concurrent spinal abnormalities that need to be monitored with MRI. There are major concerns of the MRI compatibility of MCGRs because of the reliance of the lengthening mechanism on strongly ferromagnetic actuators. METHODS: Six fresh-frozen adult cadaveric torsos were used. After thawing, MRI was performed four times each: baseline, after implantation of T2-T3 thoracic rib hooks and L5-S1 pedicle screws, and twice after MCGR implantation. Dual MCGRs were implanted in varying configurations and connected at each end with cross connectors, creating a closed circuit to maximize MRI-induced heating. Temperature measurements and tissue biopsies were obtained to evaluate thermal injury. MCGRs were tested for changes to structural integrity and functionality. MRI images obtained before and after MCGR implantation were evaluated. RESULTS: Average temperatures increased incrementally by 1.1°C, 1.3°C, and 0.5°C after each subsequent scan, consistent with control site temperature increases of 1.1°C, 0.8°C, and 0.4°C. Greatest cumulative temperature change of +3.6°C was observed adjacent to the right-sided actuator, which is below the 6°C threshold cited in literature for clinically detectable thermal injury. Histologic analysis revealed no signs of heat-induced injury. All MCGR actuators continued to function properly according to the manufacturer's specifications and maintained structural integrity. Significant imaging artifacts were observed, with the greatest amount when dual MCGRs were implanted in standard/offset configuration. CONCLUSIONS: We demonstrate minimal MRI-induced temperature change, no observable thermal tissue injury, preservation of MCGR-lengthening functionality, and no structural damage to MCGRs after multiple MRI scans. Expectedly, the ferromagnetic actuators produced substantial MR imaging artifacts. LEVEL OF EVIDENCE: Level V.

A pilot cadaveric study of temperature and adjacent tissue changes after exposure of magnetic-controlled growing rods to MRI.

PURPOSE: To test for possible thermal injury and tissue damage caused by magnetic-controlled growing rods (MCGRs) during MRI scans. METHODS: Three fresh frozen cadavers were utilized. Four MRI scans were performed: baseline, after spinal hardware implantation, and twice after MCGR implantation. Cross connectors were placed at the proximal end and at the distal end of the construct, making a complete circuit hinged at those two points. Three points were identified as potential sites for significant heating: adjacent to the proximal and distal cross connectors and adjacent to the actuators. Data collected included tissue temperatures at baseline (R1), after screw insertion (R2), and twice after rod insertions (R3 and R4). Tissue samples were taken and stained for signs of heat damage. RESULTS: There was a slight change in tissue temperature in the regions next to the implants between baseline and after each scan. Average temperatures (°C) increased by 0.94 (0.16-1.63) between R1 and R2, 1.6 (1.23-1.97) between R2 and R3, and 0.39 (0.03-0.83) between R3 and R4. Subsequent histological analysis revealed no signs of heat induced damage. CONCLUSION: Recurrent MRI scans of patients with MCGRs may be necessary over the course of treatment. When implanted into human cadaveric tissue, these rods appear to not be a risk to the patient with respect to heating or tissue damage. Further in vivo study is warranted. LEVEL OF EVIDENCE: N/A.

Writing in the granular gel medium.

Gels made from soft microscale particles smoothly transition between the fluid and solid states, making them an ideal medium in which to create macroscopic structures with microscopic precision. While tracing out spatial paths with an injection tip, the granular gel fluidizes at the point of injection and then rapidly solidifies, trapping injected material in place. This physical approach to creating three-dimensional (3D) structures negates the effects of surface tension, gravity, and particle diffusion, allowing a limitless breadth of materials to be written. With this method, we used silicones, hydrogels, colloids, and living cells to create complex large aspect ratio 3D objects, thin closed shells, and hierarchically branched tubular networks. We crosslinked polymeric materials and removed them from the granular gel, whereas uncrosslinked particulate systems were left supported within the medium for long times. This approach can be immediately used in diverse areas, contributing to tissue engineering, flexible electronics, particle engineering, smart materials, and encapsulation technologies.

Evaluation of Peripheral Vertical Nondegenerative Medial Meniscus Tears Treated With Trephination Alone at the Time of Anterior Cruciate Ligament Reconstruction.

PURPOSE: To determine (1) subjective results and incidence of symptomatic medial meniscus tears (MMTs) in patients treated with trephination alone compared with a control group without meniscus tears and (2) if trephination treatment resulted in a higher incidence of knee arthritis compared with controls with intact menisci. METHODS: Between 1997 and 2010, 419 patients met the inclusion criteria of having an isolated anterior cruciate ligament (ACL) tear, peripheral vertical nondegenerative MMT treated with trephination alone, no lateral meniscus tears, normal radiographs before surgery, and no bilateral knee involvement. A control group of 462 patients included patients who met the same criteria but without MMT. Objective data included International Knee Documentation Committee (IKDC) objective evaluation. Subjective data included IKDC and Cincinnati Knee Rating System (CKRS) scores. RESULTS: Objective follow-up was obtained for 191 patients in the study group and 200 patients in the control group (mean, 5.6 and 5.9 years, respectively; range, 2 to 16 years). Subjective survey follow-up was obtained for 312 patients in the study group and 343 patients in the control group (mean, 7.0 and 7.1 years, respectively). The mean CKRS score was 91.8 ± 13.3 for the study group and 92.3 ± 10.9 for the control group (P = .27). The mean IKDC score was 86.5 ± 15.8 for the study group and 86.7 ± 16.3 for the control group (P = .81). Subsequent MMTs occurred in 51 patients (16.3%) in the study group and 20 patients (5.8%) in the control group (P < .0001). IKDC radiographic ratings were normal for 95% of the study group and 92% of the control group (P = .18). CONCLUSIONS: Patients with peripheral nondegenerative MMTs treated with trephination alone had a 16.3% rate of subsequent symptomatic MMTs compared with 6% in patients with intact menisci. However, no statistically significant differences were found between groups for radiographic and subjective results. LEVEL OF EVIDENCE: Level III, therapeutic case control study.

Posttraumatic hypothermia increases doublecortin expressing neurons in the dentate gyrus after traumatic brain injury in the rat.

Previous studies have demonstrated that moderate hypothermia reduces histopathological damage and improves behavioral outcome after experimental traumatic brain injury (TBI). Further investigations have clarified the mechanisms underlying the beneficial effects of hypothermia by showing that cooling reduces multiple cell injury cascades. The purpose of this study was to determine whether hypothermia could also enhance endogenous reparative processes following TBI such as neurogenesis and the replacement of lost neurons. Male Sprague-Dawley rats underwent moderate fluid-percussion brain injury and then were randomized into normothermia (37°C) or hypothermia (33°C) treatment. Animals received injections of 5-bromo-2'-deoxyuridine (BrdU) to detect mitotic cells after brain injury. After 3 or 7 days, animals were perfusion-fixed and processed for immunocytochemistry and confocal analysis. Sections were stained for markers selective for cell proliferation (BrdU), neuroblasts and immature neurons (doublecortin), and mature neurons (NeuN) and then analyzed using non-biased stereology to quantify neurogenesis in the dentate gyrus (DG). At 7 days after TBI, both normothermic and hypothermic TBI animals demonstrated a significant increase in the number of BrdU-immunoreactive cells in the DG as compared to sham-operated controls. At 7 days post-injury, hypothermia animals had a greater number of BrdU (ipsilateral cortex) and doublecortin (ipsilateral and contralateral cortex) immunoreactive cells in the DG as compared to normothermia animals. Because adult neurogenesis following injury may be associated with enhanced functional recovery, these data demonstrate that therapeutic hypothermia sustains the increase in neurogenesis induced by TBI and this may be one of the mechanisms by which hypothermia promotes reparative strategies in the injured nervous system.

Oligodendrocyte vulnerability following traumatic brain injury in rats.

Experimental and clinical findings demonstrate that traumatic brain injury (TBI) results in injury to both gray and white matter structures. The purpose of this study was to document patterns of oligodendrocyte vulnerability to TBI. Sprague Dawley rats underwent sham operated procedures or moderate fluid percussion brain injury. Quantitative immunohistochemical analysis was performed on animals perfusion-fixed at 3 (n=9) or 7 (n=9) days post-surgery. Within the ipsilateral external capsule and corpus callosum, numbers of APC-CC1 immunoreactive oligodendrocytes were significantly decreased at 3 or 7 days post-TBI compared to sham rats (p<0.03). At both posttraumatic survival periods, double-labeling studies indicated that oligodendrocytes showed increased Caspase 3 activation compared to sham. These data demonstrate regional patterns of oligodendrocyte vulnerability after TBI and that oligodendrocyte cell loss may be due to Caspase 3-mediated cell death mechanisms. Further studies are needed to test therapeutic interventions that prevent trauma-induced oligodendrocyte cell death, subsequent demyelination and circuit dysfunction.

OLIGODENDROCYTE VULNERABILITY FOLLOWING TRAUMATIC BRAIN INJURY IN RATS: EFFECT OF MODERATE HYPOTHERMIA.

The purpose of this study was to document patterns of oligodendrocyte vulnerability to TBI and determine whether posttraumatic hypothermia prevents oligodendrocyte cell loss. Sprague Dawley rats underwent moderate fluid percussion brain injury. Thirty minutes after TBI, brain temperature was reduced to 33°C for 4 hrs or maintained at normothermic levels (37°C). Animals were perfusion-fixed for quantitative immunohistochemical analysis at 3 (n=9) or 7 (n=9) days post-TBI. Within the cerebral cortex, external capsule and corpus callosum, numbers of APC-CC1 immunoreactive oligodendrocytes at 3 and 7 days following TBI were significantly decreased compared to sham operated rats (p<0.02). Double-labeling studies showed that vulnerable oligodendrocytes expressed increased Caspase 3 activation compared to sham. Posttraumatic hypothermia significantly reduced the number of CC1 positive oligodendrocytes lost after normothermia TBI in white matter tracts (p<0.01). This model of TBI leads to quantifiable regional patterns of oligodendrocyte vulnerability. Posttraumatic hypothermia protects oligodendrocytes by interfering with Caspase 3-mediated cell death mechanisms. Therapeutic hypothermia may improve functional outcome by attenuating trauma-induced oligodendrocyte cell death, subsequent demyelination and circuit dysfunction.