Alignment in Total Knee Arthroplasty: Avoid Crossing Over From Varus to Valgus.

BACKGROUND: Ideal target limb alignment remains a debated topic in total knee arthroplasty (TKA). We aimed to determine the effect of limb alignment correction on patient-reported outcomes and knee range of motion (ROM) following TKA. METHODS: In this retrospective analysis, patients (N = 409) undergoing primary TKA at a single institution were studied. Using full leg-length radiographs, limb alignment was measured preoperatively and postoperatively. Patients were categorized by preoperative (Preop) alignment (varus > 0°; valgus < 0°). Preop varus patients were then divided as follows based on postoperative alignment: neutral (VAR-NEUT, 0°± 2), remaining in varus (VAR-rVAR, ≥3°), and cross-over to valgus (VAR-CO, ≤-3°). Similarly, Preop valgus patients were divided as follows for postoperative alignment: neutral (VAL-NEUT, 0°± 2), remaining in valgus (VAL-rVAL, ≤-3°), and cross-over to varus (VAL-CO, ≥3°). The Knee Injury and Osteoarthritis Outcome Score for Joint Replacement survey scores were collected at preoperatively as well as at 6 weeks, 3, 6, and 12 months postoperatively. Knee ROM was collected at 2 weeks, 6 to 12 weeks, and >6 months postoperatively. An analysis of variance repeated on time followed by a Bonferroni post hoc test was used to compare outcomes for the postoperative alignment subgroups. RESULTS: Preop Varus patients: Those in the VAR-CO group (overcorrected to -4.03° ± 1.95valgus) were observed to have lower Knee Injury and Osteoarthritis Outcome Score for Joint Replacement scores at 3, 6, and 12 months postoperatively compared to those in the NEUT group (P < .05). This finding was paired with reduced ROM at 6 to 12 weeks postoperatively in the VAR-CO group compared to VAR-NEUT and VAR-rVAR (P < .05). Preop Valgus patients: Those in the VAL-rVal group (left in -4.39° ± 1.39valgus) were observed to have reduced knee flexion at 6 to 12 weeks postoperatively compared to VAL-NEUT and VAL-CO. CONCLUSIONS: These findings indicate that postoperative valgus alignment via either crossing over to valgus (VAR-CO) or remaining in valgus (VAL-rVAL) alignment may result in less preferable outcomes than correction to neutral or slightly varus alignment.

Insulin Dependence Increases the Risk of 30-Day Postoperative Complications Following Ankle Fracture Surgery in Patients With Diabetes Mellitus.

Patients with diabetes mellitus that undergo ankle fracture surgery have higher rates of postoperative complications compared to patients without diabetes mellitus. We evaluated the rate of complications in insulin-dependent diabetes mellitus patients, non-insulin-dependent diabetes mellitus patients, and patients without diabetes in the 30-day postoperative period following ankle fracture surgery. We also analyzed hospital length of stay, unplanned readmission, unplanned reoperation, and death. Patients who underwent operative management for ankle fractures between 2012 and 2016 were identified in the American College of Surgeons National Surgical Quality Improvement Program® database using Current Procedural Terminology codes. Multiple logistic regression was implemented. Adjusted odds ratios were calculated along with the 95% confidence interval. A total of 19,547 patients undergoing ankle surgery were identified from 2012 to 2016. Of these patients, 989 (5.06%) had insulin-dependent diabetes mellitus, 1256 (6.43%) had noninsulin-dependent diabetes mellitus, and 17,302 (88.51%) did not have diabetes mellitus. Compared to patients without diabetes, patients with insulin-dependent diabetes mellitus had significantly greater adjusted odds of superficial surgical site infections, deep surgical site infections, osteomyelitis, wound dehiscence, pneumonia, unplanned intubation, mechanical ventilation, urinary tract infection, cardiac arrest, bleeding requiring transfusion, sepsis, hospital length of stay, unplanned readmission, unplanned reoperation, and death following ankle fracture surgery. We demonstrate that insulin-dependent diabetes mellitus is a strong predictor of 30-day postoperative complications, unplanned readmission, unplanned reoperation, and death following ankle fracture surgery.

The age-dependent effect of high-dose X-ray radiation on NFκB signaling, structure, and mechanical behavior of the intervertebral disc.

Purpose: Ionizing radiation damages tissue and provokes inflammatory responses in multiple organ systems. We investigated the effects of high-dose X-ray radiation on the molecular inflammation and mechanical function of the intervertebral disc (IVD).Methods: Functional spine units (FSUs) containing the vertebrae-IVDs-vertebrae structure extracted from 1-month, 6-month, and 16-month-old NFκB-luciferase reporter mice and from 6-month-old myeloid differentiation factor 88 (MyD88)-null mice. After a preconditioning period in culture, the FSUs were subjected a single dose of ionizing X-ray radiation at 20 Gys, and then NFκB expression was monitored. The IVDs were then subjected to mechanical testing using dynamic compression, glycosaminoglycan (GAG) quantification, and histological analyses.Results: In the 1-month-old FSUs, the NFκB-driven luciferase activity was significantly elevated for 1 day following the exposure to radiation. The 6-month-old FSUs showed increased NFκB activity for 3 days, while the 16-month-old FSUs sustained elevated levels of NFκB activity throughout the 10-day culture period. All irradiated groups showed significant loss of disc height, GAG content, mechanical function and changes in structure. Ablation of MyD88 blunted the radiation-mediated NFκB signaling, and preserved GAG content, and the IVDs' structure and mechanical performance.Conclusions: These results suggest that high-dose radiation affects the IVDs' NFκB-dependent inflammatory processes that subsequently lead to functional deterioration. Blocking the transactivation potential of NFκB via MyD88 ablation preserved the structure and mechanical function of the FSUs. The long-term effects of radiation on IVD homeostasis should be considered in individuals susceptible to occupational and medical exposure.

Increased Rates of Readmission, Reoperation, and Mortality Following Open Reduction and Internal Fixation of Ankle Fractures Are Associated With Diabetes Mellitus.

The purpose of this study was to compare the rates of readmission, reoperation, and mortality in patients with and without diabetes mellitus during the 30-day postoperative period after ankle fracture surgery. Patients who underwent operative management for ankle fractures between 2006 and 2015 were identified in the American College of Surgeons National Surgical Quality Improvement Program® database by using Current Procedural Terminology codes for ankle fracture surgery. A total of 17,464 patients undergoing ankle fracture surgery were identified. Of these patients, 2044 (11.7%) had diabetes and 15,420 (88.3%) did not have diabetes. We excluded patients older than 90 years or with inadequate perioperative data. Patients with diabetes had significantly higher rates of readmission (2.84% vs 1.05%, p < .0001), significantly higher rates of unplanned reoperation (2.3% vs 0.74%, p < .0001), and significantly higher rates of mortality (0.7% vs 0.2%, p < .0001) compared with patients without diabetes. Additionally, patients with diabetes had significantly greater age-adjusted odds ratios (ORs) of unplanned readmission (OR 2.40, 95% confidence interval [CI] 1.74 to 3.31, p < .0001), unplanned reoperation (OR 2.56, 95% CI 1.44 to 3.27, p < .0001), and mortality (OR 2.01, 95% CI 1.08 to 3.62, p = .0432) than did patients without diabetes after ankle surgery. In this large-scale retrospective study, we demonstrated that the presence of diabetes significantly increases the risk of unplanned readmission, unplanned reoperation, and mortality during the 30-day postoperative period after ankle fracture surgery.

The language of all medical publications and spine publications from 1950 to 2020.

Background: Excellent research in all fields, including spine surgery, exists in many different regions and languages. This study seeks to determine the relative number of spine related peer-reviewed publications throughout the world based on language. Methods: Peer-reviewed publications from the eleven most prolific languages in regard to both the number of peer-reviewed spine publications indexed in PubMed and total peer-reviewed publications from 1950-2020 were identified in PubMed. Results: 29,711,547 peer-reviewed publications were analyzed for the languages of interest with 870,404 (3.0%) of those being spine related peer-reviewed publications. Between 1988 and 2019, non-English language peer-reviewed publications decreased annually for both all peer-reviewed publications and spine related peer-reviewed publications by 44% and 36%, respectively. All medical and spine specific peer reviewed publications in English compared to non-English publications have increased by 7.22 and 6.35 times since 1988, respectively. While the ratio of non-English to English spine related publications decreased in all eleven countries, the percentage of the number of spine specific publications written in Chinese (462%), Portuguese (378%), and Spanish (88%) have increased by the listed percentages. Conclusion: While the proportion of peer-reviewed publications in the field of spine surgery written in English have increased over the past several decades, there are many non-English language peer-reviewed publications each year, particularly in Chinese. Although the rapid increase in the proportion of English spine related publications is beneficial to English speaking physicians and researchers, further research is necessary to understand the impact on non-English speaking physicians and researchers.

Does Size Matter for Cephalomedullary Nails in Geriatric Intertrochanteric Fractures?

OBJECTIVES: To evaluate the need for reoperation of geriatric intertrochanteric hip fractures treated with 10-mm cephalomedullary nails versus those treated with nails larger than 10 mm. DESIGN: Retrospective review at a single institution. SETTING: Level I trauma center. PATIENTS/PARTICIPANTS: All patients age 60 and over treated with cephalomedullary fixation for an intertrochanteric femur fracture at a single institution. INTERVENTION: Cephalomedullary fixation with variable nail diameters. MAIN OUTCOME MEASUREMENTS: Reoperation rates of geriatric intertrochanteric fractures treated with a size 10-mm diameter cephalomedullary nail compared with patients treated with nails larger than 10 mm. RESULTS: There were no significant differences in reoperation rates when the 10-mm cohort was compared with an aggregate cohort of all nails larger than 10 mm (P = 0.99). This result was true for both all-cause reoperation and noninfectious reoperation. There was no difference between cohorts in regards to age, gender, or fracture pattern. CONCLUSIONS: A 10-mm cephalomedullary nail can be used in lieu of a larger diameter fixation in patients age 60 and older with intertrochanteric femur fractures while still maintaining a comparable rate of reoperation. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Relations Between Bone Quantity, Microarchitecture, and Collagen Cross-links on Mechanics Following In Vivo Irradiation in Mice.

Humans are exposed to ionizing radiation via spaceflight or cancer radiotherapy, and exposure from radiotherapy is known to increase risk of skeletal fractures. Although irradiation can reduce trabecular bone mass, alter trabecular microarchitecture, and increase collagen cross-linking, the relative contributions of these effects to any loss of mechanical integrity remain unclear. To provide insight, while addressing both the monotonic strength and cyclic-loading fatigue life, we conducted total-body, acute, gamma-irradiation experiments on skeletally mature (17-week-old) C57BL/6J male mice (n = 84). Mice were administered doses of either 0 Gy (sham), 1 Gy (motivated by cumulative exposures from a Mars mission), or 5 Gy (motivated by clinical therapy regimens) with retrieval of the lumbar vertebrae at either a short-term (11-day) or long-term (12-week) time point after exposure. Micro-computed tomography was used to assess trabecular and cortical quantity and architecture, biochemical composition assays were used to assess collagen quality, and mechanical testing was performed to evaluate vertebral compressive strength and fatigue life. At 11 days post-exposure, 5 Gy irradiation significantly reduced trabecular mass (p < 0.001), altered microarchitecture (eg, connectivity density p < 0.001), and increased collagen cross-links (p < 0.001). Despite these changes, vertebral strength (p = 0.745) and fatigue life (p = 0.332) remained unaltered. At 12 weeks after 5 Gy exposure, the trends in trabecular bone persisted; in addition, regardless of irradiation, cortical thickness (p < 0.01) and fatigue life (p < 0.01) decreased. These results demonstrate that the highly significant effects of 5 Gy total-body irradiation on the trabecular bone morphology and collagen cross-links did not translate into detectable effects on vertebral mechanics. The only mechanical deficits observed were associated with aging. Together, these vertebral results suggest that for spaceflight, irradiation alone will likely not alter failure properties, and for radiotherapy, more investigations that include post-exposure time as a positive control and testing of both failure modalities are needed to determine the cause of increased fracture risk. © 2021 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research. This article has been contributed to by US Government employees and their work is in the public domain in the USA.

An In Vitro Organ Culture Model of the Murine Intervertebral Disc.

Intervertebral disc (IVD) degeneration is a significant contributor to low back pain. The IVD is a fibrocartilaginous joint that serves to transmit and dampen loads in the spine. The IVD consists of a proteoglycan-rich nucleus pulposus (NP) and a collagen-rich annulus fibrosis (AF) sandwiched by cartilaginous end-plates. Together with the adjacent vertebrae, the vertebrae-IVD structure forms a functional spine unit (FSU). These microstructures contain unique cell types as well as unique extracellular matrices. Whole organ culture of the FSU preserves the native extracellular matrix, cell differentiation phenotypes, and cellular-matrix interactions. Thus, organ culture techniques are particularly useful for investigating the complex biological mechanisms of the IVD. Here, we describe a high-throughput approach for culturing whole lumbar mouse FSUs that provides an ideal platform for studying disease mechanisms and therapies for the IVD. Furthermore, we describe several applications that utilize this organ culture method to conduct further studies including contrast-enhanced microCT imaging and three-dimensional high-resolution finite element modeling of the IVD.

Longitudinal changes in the structure and inflammatory response of the intervertebral disc due to stab injury in a murine organ culture model.

Despite the significant public health impact of intervertebral disc (IVD) degeneration and low back pain, it remains challenging to investigate the multifactorial molecular mechanisms that drive the degenerative cascade. Organ culture model systems offer the advantage of allowing cells to live and interact with their native extracellular matrix, while simultaneously reducing the amount of biological variation and complexity present at the organismal level. Murine organ cultures in particular also allow the use of widely available genetically modified animals with molecular level reporters that would reveal insights on the degenerative cascade. Here, we utilize an organ culture system of murine lumbar functional spinal units where we are able to maintain the cellular, metabolic, and structural, and mechanical stability of the whole organ over a 21-day period. Furthermore, we describe a novel approach in organ culture by using tissues from animals with an NF-κB-luc reporter in combination with a mechanical injury model, and are able to show that proinflammatory factors and cytokines such as NF-κB and IL-6 produced by IVD cells can be monitored longitudinally during culture in a stab injury model. Taken together, we utilize a murine organ culture system that maintains the cellular and tissue level behavior of the intervertebral disc and apply it to transgenic animals that allow the monitoring of the inflammatory profile of IVDs. This approach could provide important insights on the molecular and metabolic mediators that regulate the homeostasis of the IVD. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1431-1438, 2016.

The high-throughput phenotyping of the viscoelastic behavior of whole mouse intervertebral discs using a novel method of dynamic mechanical testing.

Intervertebral disc (IVD) degeneration is highly correlated with lower back pain, and thus understanding the mechanisms of IVD degeneration is critical for the treatment of this disease. Utilizing mouse models to probe the mechanisms of degeneration is especially attractive due to the ease of manipulating mouse models and the availability of transgenics. Yet characterizing the mechanical behavior of mice IVDs remain challenging due to their minute size (approximately 540 µm in height and 1080 µm(2) in cross sectional area). We have thus developed a simple method to dynamically characterize the mechanical properties of intact mouse IVDs. The IVDs were dissected with the endplates intact, and dynamically compressed in the axial direction at 1% and 5% peak strains at 1 Hz. Utilizing this novel approach, we examined the effects of in vitro ribosylation and trypsin digestion for 24 or 72 h on the viscoelastic behavior of the whole murine IVD. Trypsin treatment resulted in a decrease of proteoglycans and loss of disc height, while ribosylation had no effect on structure or proteoglycan composition. The 72 h ribosylation group exhibited a stiffening of the disc, and both treatments significantly reduced viscous behavior of the IVDs, with the effects being more pronounced at 5% strain. Here we demonstrate a novel high-throughput method to mechanically characterize murine IVDs and detect strain-dependent differences in the elastic and the viscous behavior of the treated IVDs due to ribose and trypsin treatments.