Regeneration in Spinal Disease: Therapeutic Role of Hypoxia-Inducible Factor-1 Alpha in Regeneration of Degenerative Intervertebral Disc.

The intervertebral disc (IVD) is a complex joint structure comprising three primary components-namely, nucleus pulposus (NP), annulus fibrosus (AF), and cartilaginous endplate (CEP). The IVD retrieves oxygen from the surrounding vertebral body through CEP by diffusion and likely generates ATP via anaerobic glycolysis. IVD degeneration is characterized by a cascade of cellular, compositional, structural changes. With advanced age, pronounced changes occur in the composition of the disc extracellular matrix (ECM). NP and AF cells in the IVD possess poor regenerative capacity compared with that of other tissues. Hypoxia-inducible factor (HIF) is a master transcription factor that initiates a coordinated cellular cascade in response to a low oxygen tension environment, including the regulation of numerous enzymes in response to hypoxia. HIF-1α is essential for NP development and homeostasis and is involved in various processes of IVD degeneration process, promotes ECM in NP, maintains the metabolic activities of NP, and regulates dystrophic mineralization of NP, as well as angiogenesis, autophagy, and apoptosis during IVD degeneration. HIF-1α may, therefore, represent a diagnostic tool for early IVD degeneration and a therapeutic target for inhibiting IVD degeneration.

Incidence and treatment trends of infectious spondylodiscitis in South Korea: A nationwide population-based study.

The incidence of infectious spondylodiscitis (IS) has increased in recent years due to an increase in the numbers of older patients with chronic diseases, as well as patients with immunocompromise, steroid use, drug abuse, invasive spinal procedures, and spinal surgeries. However, research focusing on IS in the general population is lacking. This study investigated the incidence and treatment trends of IS in South Korea using data obtained from the Health Insurance Review and Assessment Service. A total of 169,244 patients (mean age: 58.0 years) diagnosed from 2010 to 2019 were included in the study. A total of 10,991 cases were reported in 2010 and 18,533 cases in 2019. Hence, there was a 1.5-fold increase in incidence rate per 100,000 people from 22.90 in 2010 to 35.79 in 2019 (P < 0.05). The incidence rate of pyogenic spondylodiscitis per 100,000 people increased from 15.35 in 2010 to 33.75 in 2019, and that of tuberculous spondylodiscitis decreased from 7.55 in 2010 to 2.04 in 2019 (P < 0.05, respectively). Elderly individuals ≥ 60 years of age accounted for 47.6% (80,578 patients) of all cases of IS. The proportion of patients who received conservative treatment increased from 82.4% in 2010 to 85.8% in 2019, while that of patients receiving surgical treatment decreased from 17.6% to 14.2% (P < 0.05, respectively). Among surgical treatments, the proportions of corpectomy and anterior fusion declined, while proportion of incision and drainage increased (P < 0.05, respectively). The total healthcare costs increased 2.9-fold from $29,821,391.65 in 2010 to $86,815,775.81 in 2019 with a significant increase in the ratio to gross domestic product. Hence, this population-based cohort study demonstrated that the incidence rate of IS has increased in South Korea. The conservative treatment has increased, while the surgical treatment has decreased. The socioeconomic burden of IS has increased rapidly.

Risk Factors of Flexor Tendon Rupture After ORIF of Distal Radius Fracture.

OBJECTIVES: To analyze the risk factors associated with postoperative flexor tendon rupture, after a volar plate fixation of distal radius fractures. DESIGN: Retrospective observational case-control study. SETTING: Tertiary Care University Hospital in the Republic of Korea (2009-2020). PATIENTS: Sixteen referred patients were treated for flexor tendon rupture, following previously performed volar plating of distal radius fractures at other institutions. 16 patients were randomly selected from our database as controls, and were matched based on the Soong grade of the case group. INTERVENTION: Not applicable. MAIN OUTCOME MEASUREMENTS: Radial tilt and radial height were measured on anteroposterior radiographs. The volar tilt, tear drop angle, carpal translation, and Soong grade were measured in a lateral view. RESULTS: Quantitative measurements of the volar tilt, carpal translation, and tear drop angle were positively correlated with the flexor tendon rupture. The mean volar tilt and tear drop angle in the tendon rupture group were significantly smaller than those in the control group. The mean carpal translation in the tendon rupture group was significantly greater than that in the control group. CONCLUSIONS: This study demonstrated that volar tilt, carpal translation, and tear drop angle are significant risk factors for flexor tendon rupture, especially for plates placed at Soong grade 1 or 2. We suggest that the potential for tendon rupture because of incomplete reduction of the distal radius fracture along with implant prominence volar to the watershed line aggravates flexor tendon irritation at the distal edge of the plate because of distorted flexor tendon paths. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Erratum to "Clavicular Tunnel Complications after Coracoclavicular Reconstruction in Acute Acromioclavicular Dislocation: Coracoid Loop versus Coracoid Tunnel Fixation".

[This corrects the article on p. 128 in vol. 14, PMID: 35251550.].