Cochlear spiral ganglion neurons (SGNs) are bipolar ganglion cells and are the first neurons in the auditory transduction pathway. They transmit complex acoustic information from hair cells to second-order sensory neurons in the cochlear nucleus for sound processing. Injury to SGNs causes largely irreversible hearing impairment because these neurons are highly differentiated cells and cannot regenerate, making treatment of sensorineural hearing loss (SNHL) arising from SGN injury difficult. When exposed to ototoxic drugs or damaging levels of noise or when there is loss of neurotrophic factors (NTFs), aging, and presence of other factors, SGNs can be irreversibly damaged, resulting in SNHL. It has been found that NTFs and stem cells can induce regeneration among dead spiral ganglion cells. In this paper, we summarized the present knowledge regarding injury, protection, and regeneration of SGNs.

PURPOSE: Periprosthetic fracture (PPF) is a serious complication that occurs in 0.3%-2.5% of all total knee arthroplasties used to treat end-stage arthritis. To our knowledge, there are no studies in the literature that evaluate the association between time to surgery after PPF and early postoperative infections or deep vein thrombosis (DVT). This study tests our hypothesis that delayed time to surgery increases rates of postoperative infection and DVT after PPF surgery. METHODS: Our study cohort included patients undergoing PPF surgery in the American College of Surgeons National Surgical Quality Improvement Program database (2006-2015). The patients were dichotomized based on time to surgery: group 1 with time ≤2 days and group 2 with time >2 days. A 2-by-2 contingency table and Fisher's exact test were used to evaluate the association between complications and time to surgery groups, and multivariate logistic regression was used to adjust for demographics and known risk factors. RESULTS: A total of 263 patients (80% females) with a mean age of 73.9 ± 12.0 years were identified receiving PPF surgery, among which 216 patients were in group 1 and 47 patients in group 2. Complications in group 1 included 3 (1.4%) superficial infections (SI), 1 (0.5%) organ space infection (OSI), 1 (0.5%) wound dehiscence (WD), and 4 (1.9%) deep vein thrombosis (DVT); while complications in group 2 included 1 (2.1%) SI, 1 (2.1%) OSI, 1 (2.1%) DVT, and no WD. No significant difference was detected in postoperative complications between the two groups. However, patients in group 2 were more likely (p = 0.0013) to receive blood transfusions (57.5%) than those in group 1 (32.4%). CONCLUSION Our study indicates patients with delayed time to surgery have higher chance to receive blood transfusions, but no significant difference in postoperative complications (SI, OSI, WD, or DVT) between the two groups.
Aged ; Aged, 80 and over ; Arthroplasty, Replacement, Knee ; adverse effects ; Blood Transfusion ; statistics & numerical data ; Cohort Studies ; Female ; Humans ; Infection ; epidemiology ; Logistic Models ; Male ; Middle Aged ; Periprosthetic Fractures ; etiology ; surgery ; Postoperative Complications ; epidemiology ; Risk Factors ; Surgical Wound Dehiscence ; epidemiology ; Surgical Wound Infection ; epidemiology ; Time Factors ; Venous Thrombosis ; epidemiology