Pharmacologic Recruitment of Endogenous Neural Stem/Progenitor Cells for the Treatment of Spinal Cord Injury

STUDY DESIGN

Laboratory study using a rat T9 contusion model of spinal cord injury.

OBJECTIVE

This study aims to examine whether a combinatory treatment of Pioglitazone (PGZ) and granulocyte colony-stimulating factor (GCSF) can support neural stem/progenitor cells (NSPCs) directly and provide a sustainable microenvironment through immunomodulatory mechanisms.

SUMMARY OF BACKGROUND DATA

Neuroinflammation plays a crucial role in the progression of spinal cord injury (SCI) and hinders NSPC-mediated repair and regeneration. Broad acting drugs that mitigate inflammation and support NSPC proliferation have not been tested together in SCI research models.

METHODS

Isolated NSPCs were treated with vehicle control, PGZ, GCSF, or both PGZ and GSCF for 24 hours and stained with proliferation marker Ki67. Adult female Sprague-Dawley rats sustained moderate-to-severe contusion-based SCI at T9 and were administered either vehicle control, PGZ, GCSF, or both PGZ and GCSF treatments.

RESULTS

Immunocytochemistry revealed that cultured NSPCs treated with both drugs produced higher numbers of actively proliferating cells and total cell numbers. ELISA on spinal cord tissue lysates at 1, 3, and 7 days post-injury (DPI) demonstrated that animals treated with PGZ, GCSF, or combination therapy showed significantly higher doublecortin levels at 7 DPI compared to control animals (P < 0.05). Immunohistochemistry of injured tissue at 3, 7, and 14 DPI revealed no difference of ependymal NSPC proliferation between groups, but showed a significant decrease in lesion size with combination therapy compared to controls. Functional recovery was assessed by the Basso, Beattie, Bresnahan locomotor rating scale. Animals treated with both drugs had significantly higher levels of function at 1 (P < 0.001), 3 (P < 0.001), 7 (P < 0.05), and 14 (P < 0.05) DPI compared to controls.

CONCLUSION

These results indicate that PGZ and GCSF treatment synergistically enhance NSPCs numbers and improve functional recovery after SCI. Our findings support an immunomodulatory strategy to recruit native NSPCs as a potential acute care intervention for SCI.Level of Evidence: N/A.

Gout As a Predictor of Total Knee Arthroplasty Outcomes and Costs

Gout is the most common inflammatory arthritis and affects approximately 4% of the U.S. population. As the prevalence of gout and the number of total knee arthroplasties (TKAs) performed continue to increase, the literature on TKA in patients with gout remains scant. The purpose of this study was to evaluate the outcomes of patients with gout following TKA at a population level, that is, how patient with gout fair after TKA. We hypothesized that patients with gout have higher rates of complications and higher costs compared with controls. A case-control study was designed to evaluate two cohorts of Medicare patients who underwent TKA whose only distinguishing feature was the presence or absence of gout. Matching was performed to decrease confounding at a 1:1 ratio based on age, gender, and Charlson comorbidity index (CCI), (10-year survival predictor). The Medicare standard analytical files were queried through International Classification of Disease and current procedural terminology codes. A total of 15,238 patients were evaluated with 7,619 in each cohort. There were no age, gender, or CCI differences and 57.4% were females. Day of surgery and 90-day post-surgery costs were both significantly greater in those with gout (p < 0.001 for both). Multivariate analysis revealed that gout patients had increased odds of infection (odds ratio [OR] 1.229, p = 0.019), cardiac arrest (OR 1.354, p = 0.002), pneumonia (OR 1.161, p < 0.001), hematoma (OR 1.204, p = 0.002), and development of capsulitis (OR 1.208, p = 0.012). Nonetheless these patients had a decreased risk of pulmonary emboli (OR 0.835, p = 0.016). Our results support our hypothesis that patients with gout have higher rates of postoperative complications and increased day of surgery and 90-day costs of care after TKA. Given the high prevalence of gout in the United States, additional study on the utility of preoperative gout optimization for TKA patients is warranted. The level of evidence of this study is III, and it is a retrospective case-control study.

Keratin Biomaterials Improve Functional Recovery in a Rat Spinal Cord Injury Model

STUDY DESIGN

Laboratory study using a rat T9 contusion model of spinal cord injury (SCI).

OBJECTIVE

The purpose of this study was to evaluate which method of delivery of soluble keratin biomaterials would best support functional restoration through the macrophage polarization paradigm.

SUMMARY OF BACKGROUND DATA

SCI is a devastating neurologic event with complex pathophysiological mechanisms that currently has no cure. After injury, macrophages and resident microglia are key regulators of inflammation and tissue repair exhibiting phenotypic and functional plasticity. Keratin biomaterials have been demonstrated to influence macrophage polarization and promote the M2 anti-inflammatory phenotype that attenuates inflammatory responses.

METHODS

Anesthetized female Lewis rats were subjected to moderate T9 contusion SCI and randomly divided into: no therapy (control group), an intrathecally injected keratin group, and a keratin-soaked sponge group (n = 11 in all groups). Functional recovery assessments were obtained at 3- and 6-weeks post-injury (WPI) using gait analysis performed with the DigiGait Imaging System treadmill and at 1, 3, 7, 14, 21, 28, 35, and 42 days post-injury by the Basso, Beattie, Bresnahan (BBB) locomotor rating scale. Histology and immunohistochemistry of serial spinal cord sections were performed to assess injury severity and treatment efficacy.

RESULTS

Compared to control rats, applying keratin materials after injury improved functional recovery in certain gait parameters and overall trended toward significance in BBB scores; however, no significant differences were observed with tissue analysis between groups at 6 WPI.

CONCLUSION

Results suggest that keratin biomaterials support some locomotor functional recovery and may alter the acute inflammatory response by inducing macrophage polarization following SCI. This therapy warrants further investigation into treatment of SCI.Level of Evidence: N/A.

Clinical presentation, imaging findings, and arthroscopic features in skeletally immature and mature adolescent hip patients: a comparative double-cohort retrospective study

The purpose of this study was to evaluate differences in clinical presentation and extent of surgery required based on skeletal maturity between two cohorts of adolescent hip arthroscopy patients. We hypothesized that skeletal immaturity would be associated with a lower frequency of pincer impingement and a decreased need for surgical acetabuloplasty. A database of 1481 hip arthroscopies performed by a single orthopaedic surgeon between 2008 and 2016 was queried. Patients ≤18 years of age with femoroacetabular impingement were divided into two groups based on Risser score: Risser 1-4 (skeletally immature) or Risser 5 (skeletally mature). Groups were compared with respect to presentation, diagnosis, and arthroscopic procedures performed. Eighty-eight skeletally immature and 49 skeletally mature patients were included. Mixed impingement was more common in skeletally mature patients than immature (67.3% vs. 48.9%, P = 0.037). Skeletal maturity was associated with a significantly increased probability of undergoing acetabuloplasty (odds ratio = 4.6, 95% confidence interval 1.4-15.5; P = 0.014). Extent of chondral degeneration was similar between groups. Our findings support the hypothesis that skeletally immature hips undergo acetabuloplasty less frequently and demonstrate similar chondromalacia compared with a skeletally mature cohort. These results suggest that arthroscopic treatment for impingement-associated hip pain may be a reasonable option to consider for symptomatic skeletally immature patients who have completed a structured course of nonoperative treatment. Additional longitudinal outcomes data are needed to clarify the natural history of impingement-associated hip pain in younger populations and whether hip arthroscopy delays progression of osteoarthritis in these patients.

The modified anterior ellipsoidal cap titanium cable tension band for comminuted patellar fractures

PURPOSE

The purpose of this study was to assess the outcomes in a series of patients, who underwent cerclage and figure-of-eight tension band wiring using a single titanium cable for comminuted patellar fractures.

METHODS

We describe a modified tension band technique using a single titanium cable to create an ellipsoidal cap structure that combines the circumferential and figure-of-eight wrapping in the fixation of closed Association for the Study of Internal Fixation/Orthopaedic Trauma Association 34C2 and 34C3 patellar fractures. We retrospectively reviewed 25 patients (16 males and 9 females, mean age 54 years) who underwent the described fixation technique between 2015 and 2017. Postoperative function was evaluated using the Böstman score.

RESULTS

At the mean follow-up of 25 months (range 17-39 months), the mean Böstman score was 27.3 ± 2.6 points (range 23-30). Eighteen patients (72%) had excellent results (score ≥28); seven patients (28%) had good results (score 20-27); and no patients had an unsatisfactory result (score < 20). All surgical incisions healed without major wound complications. Two patients reported minor complications (soft tissue irritation, cellulitis). No patients demonstrated loss of reduction or implant failure during the follow-up period.

CONCLUSION

The modified anterior ellipsoidal cap tension band using a single titanium cable created an effective tension band structure in the treatment of comminuted patella fractures. It is a simple operative technique that produced a stable fixation construct, which allowed early functional rehabilitation and weight-bearing with a high rate of excellent outcomes at 2 years after surgery.

[Mental health survey of medical staff in a tertiary infectious disease hospital for COVID-19]

Objective: To investigate the mental health of clinical first-line medical staff in COVID-19 epidemic and provide theoretical basis for psychological intervention. Methods: The mental health status of the first-line medical staff was investigated by Self-rating Anxiety Scale(SAS) and Post-Traumatic Stress Disorder Self- rating Scale (PTSD-SS). From February 7 to 14, 2020, 246 medical staff participated in the treatment of COVID-19 were investigated using cluster sampling, and received 230 responses, with a recovery rate of 93.5%. Results: The incidence of anxiety in medical staff was 23.04% (53/230) , and the score of SAS was(42.91±10.89). Among them, the incidence of severe anxiety, moderate anxiety and mild anxiety were 2.17%(5/230) , 4.78%(11/230) and 16.09%(37/230) , respectively. The incidence of anxiety in female medical staff was higher than that in male [25.67%(48/187) vs 11.63%(5/43) , Z=-2.008, P=0.045], the score of SAS in female medical staff was higher than that in male [(43.78±11.12) vs (39.14±9.01) , t=-2.548, P=0.012]. The incidence of anxiety in nurses was higher than that in doctors[26.88% (43/160) vs 14.29% (10/70) , Z=-2.066, P=0.039], and the score of SAS in nurses was higher than that in doctors [ (44.84±10.42) vs (38.50±10.72) , t=-4.207, P<0.001]. The incidence of stress disorder in medical staff was 27.39% (63/230) , and the score of PTSD-SS was (42.92±17.88) . The score of PTSD-SS in female medical staff was higher than that in male[ (44.30±18.42) vs (36.91±13.95) , t=-2.472, P=0.014]. Conclusion: In COVID-19 epidemic , the incidence of anxiety and stress disorder is high among medical staff. Medical institutions should strengthen the training of psychological skills of medical staff. Special attention should be paid to the mental health of female nurses.

Short-term safety and effectiveness of a second-generation motion-guided total knee system

BACKGROUND

Modern knee prostheses are designed to more closely replicate normal knee kinematics. The JOURNEY II Bi-Cruciate Stabilized Total Knee System (Smith & Nephew Inc., Memphis, TN) is a second-generation motion-guided knee system that demonstrates axial rotation patterns during flexion, which resemble those of the normal knee. The aim of this study was to assess the short-term safety and effectiveness of this system in standard clinical practice.

METHODS

A total of 186 subjects (209 primary total knee arthroplasties [TKAs]) were enrolled at 12 U.S. sites. Subjects were operated on between December 2011 and October 2013 and followed for 24 months. Radiographic, clinical, and patient-reported outcome data were collected at 6-, 12-, and 24-month postoperatively.

RESULTS

At 24-month follow-up, the average objective Knee Society Score was 96.20 (standard deviation [SD] = 6.63), the average satisfaction score was 35.22 (SD = 6.63), the average expectation score was 10.91 (SD = 3.16), and the average functional activities score was 81.49 (SD = 14.65). On a 0-10 scale, pain level for walking was 0.79 (SD = 1.51) and 1.50 (SD = 1.97) for climbing stairs or inclines. The cumulative incidence of reoperation at 2-year follow-up was 1.48% (95% confidence interval [CI] 0.48%-4.52%). Ten TKAs in 7 patients were treated with closed manipulations for stiffness. Iliotibial band syndrome was reported in 2 TKAs. Two deep infections occurred, 1 requiring reoperation. No dislocations occurred in the study cohort.

CONCLUSIONS

In short-term follow-up, the JOURNEY II Bi-Cruciate Stabilized Guided Motion Total Knee System appears to be a safe and effective device for TKA.

Ascorbic Acid and Its Clinical Role in Orthopaedic Surgery

Ascorbic acid (vitamin C) is an essential micronutrient with evidence supporting its role in bone formation, tissue repair, and collagen production. Its clinical importance to the field of orthopaedic surgery has yet to be fully defined. Several observational studies have shown improved bone density and reduced hip fracture risk with supplementation. Its effect on bone fracture and soft tissue injury has been promising in animal models, but is not adequately studied in human trials. Results have been mixed concerning its role in chondroprotection and osteoarthritis treatment. Evidence suggesting reduced incidence of complex regional pain syndrome following distal radius fracture when treated with adjuvant ascorbic acid has prompted much debate but has received an endorsement of moderate support from the American Academy of Orthopaedic Surgeons. Given its potential benefits, low cost, and safety profile, ascorbic acid supplementation warrants consideration by orthopaedic surgeons in the treatment of a variety of musculoskeletal injuries (Journal of Surgical Orthopaedic Advances 27(4):261-268, 2018).

Treatment of symptomatic non-unions of the base of the ulnar styloid with plate osteosynthesis

The purpose of this prospective case series was to assess the efficacy of plate osteosynthesis using a low profile distal ulna plate for the management of persistently symptomatic non-unions of the base of the ulnar styloid. Six consecutive patients underwent resection of the non-union and plate osteosynthesis with a 2.0 mm distal ulna hook plate. Post-operative measurements of mean pain scores, QuickDASH scores, grip strength, and range of motion parameters showed significant improvements compared with the pre-operative values. No complications were reported at a mean follow-up of 25 months. The present study presents an alternative method for treating symptomatic ulnar styloid non-unions that provides stable fixation with low risk of implant removal.

LEVEL OF EVIDENCE

Therapeutic IV.

A chronically-denervated versus a freshly-harvested autograft for nerve repair in rats

Objectives

Autologous nerve grafting remains the gold standard for repair of peripheral nerve injuries. Its use, however, is limited by donor nerve availability and donor site morbidity. This is especially problematic after failure of an initial autograft that requires a repeat nerve graft, resulting in a second surgical site with associated morbidity. Based on the molecular differences in nerve degeneration in the proximal and distal segments after transection, we hypothesized that a chronically-denervated proximal stump may be viable for autologous nerve repair.

Methods

20 Sprague-Dawley rats underwent right sciatic nerve excision and sural nerve transection. After 8 weeks, nerve repair was performed by harvesting the proximal segment of the sural nerve (n=10) or a fresh sural nerve (n=10) from the contralateral hind limb. Electrophysiological changes were analyzed to compare the fresh and denervated grafts.

Results

Electrophysiological testing demonstrated higher compound motor action potential in the denervated group compared to the fresh autograft group, however this difference was not statistically significant (p=0.117).

Conclusion

The proximal segment of a chronically-denervated sural nerve can be as effective as a fresh sural nerve for autologous repair of peripheral nerve injuries in a rodent model.