Do peri-operative parathyroid hormone (PTH) analogues improve bone density and decrease mechanical complications in spinal deformity correction?-a minimum 2-year radiological study measuring Hounsfield units.

OBJECTIVE: To delineate whether use of a PTH analogue in the 1-year peri-operative period improves lumbar bone density. METHODS: A prospectively collected data registry of 254 patients who underwent CMIS correction of ASD (Cobb angle > 20 or SVA > 50 mm or (PI-LL) > 10) from Jan 2011 to Jan 2020 was analysed. Patients who were placed on PTH analogues for one year in conjunction with surgery were included in the study. Ultimately, 41 patients who had pre- and two-year post-operative CT scans for review were included in this study. Hounsfield units were measured off of the L1-L3 levels for all patients before and after surgery on pre-op and post-op CT scans. RESULT: The mean age of patients in this study was 70 (52-84, SD 7). Mean follow-up was 66 (24-132, SD 33) months. Twenty-three patients met criteria for severe deformity (Cobb angle > 50 degrees or SVA > 95 mm or PI/LL mismatch > 20 or PT > 30). Based off 2-year post-op CT scan, there were significant improvements in L1 Hounsfield units when comparing pre-op values (96; SD 55) to post-op values (185 SD 102); p. < 0.05. There was no screw loosening or screw pull out. There were 2 patients with PJF (4.8%). Both these patients had not completed their PTH treatment: one only took PTH for 3 months (PJF at 2-year post-op) and the other one took it only for 1 month (PJF at 1-year post-op). No increase in bone density was noted (based off of Hounsfield units) in five patients (12%) despite completion of their PTH therapy. Only one patient experienced nausea from PTH therapy. There were no other PTH related adverse events. CONCLUSION: The incidence of PTH analogues failing to increase bone density in our series was low at 12%. This study shows that PTH analogues may be a powerful adjunct for increasing bone density and may help to mitigate the risk of mechanical complications in patients undergoing deformity correction with minimally invasive techniques. Future comparative studies are warranted to confirm these latter findings and to potentially protocolize the ideal peri-operative bone health optimization strategy.

Does the Global Alignment and Proportion score predict mechanical complications in circumferential minimally invasive surgery for adult spinal deformity?

OBJECTIVE: The Global Alignment and Proportion (GAP) score was developed to serve as a tool to predict mechanical complication probability in patients undergoing surgery for adult spinal deformity (ASD), serving as an aid for setting surgical goals to decrease the prevalence of mechanical complications in ASD surgery. However, it was developed using ASD patients for whom open surgical techniques were used for correction. Therefore, the purpose of this study was to assess the applicability of the score for patients undergoing circumferential minimally invasive surgery (cMIS) for correction of ASD. METHODS: Study participants were patients undergoing cMIS ASD surgery without the use of osteotomies with a minimum of four levels fused and 2 years of follow-up. Postoperative GAP scores were calculated for all patients, and the association with mechanical failure was analyzed. RESULTS: The authors identified 182 patients who underwent cMIS correction of ASD. Mechanical complications were found in 11.1% of patients with proportioned spinopelvic states, 20.5% of patients with moderately disproportioned spinopelvic states, and 18.8% of patients with severely disproportioned spinopelvic states. Analysis with a chi-square test showed a significant difference between the cMIS and original GAP study cohorts in the moderately disproportioned and severely disproportioned spinopelvic states, but not in the proportioned spinopelvic states. CONCLUSIONS: For patients stratified into proportioned, moderately disproportioned, and severely disproportioned spinopelvic states, the GAP score predicted 6%, 47%, and 95% mechanical complication rates, respectively. The mechanical complication rate in patients undergoing cMIS ASD correction did not correlate with the calculated GAP spinopelvic state.

Chances of Mortality Are 3.5-Times Greater in Elderly Patients with Umbilical Hernia Than in Adult Patients: An Analysis of 21,242 Patients.

The goal of this study was to identify risk factors that are associated with mortality in adult and elderly patients who were hospitalized for umbilical hernia. A total of 14,752 adult patients (ages 18−64 years) and 6490 elderly patients (ages 65+), who were admitted emergently for umbilical hernia, were included in this retrospective cohort study. The data were gathered from the National Inpatient Sample (NIS) 2005−2014 database. Predictors of mortality were identified via a multivariable logistic regression, in patients who underwent surgery and those who did not for adult and elderly age groups. The mean (SD) ages for adult males and females were 48.95 (9.61) and 46.59 (11.35) years, respectively. The mean (SD) ages for elderly males and females were 73.62 (6.83) and 77.31 (7.98) years, respectively. The overall mortality was low (113 or 0.8%) in the adult group and in the elderly group (179 or 2.8%). In adult patients who underwent operation, age (OR = 1.066, 95% CI: 1.040−1.093, p < 0.001) and gangrene (OR = 5.635, 95% CI: 2.288−13.874, p < 0.001) were the main risk factors associated with mortality. Within the same population, female sex was found to be a protective factor (OR = 0.547, 95% CI: 0.351−0.854, p = 0.008). Of the total adult sample, 43% used private insurance, while only 18% of patients in the deceased population used private insurance. Conversely, within the entire adult population, only about 48% of patients used Medicare, Medicaid, or self-pay, while these patients made up 75% of the deceased group. In the elderly surgical group, the main risk factors significantly associated with mortality were frailty (OR = 1.284, 95% CI: 1.105−1.491, p = 0.001), gangrene (OR = 13.914, 95% CI: 5.074−38.154, p < 0.001), and age (OR = 1.034, 95% CI: 1.011−1.057, p = 0.003). In the adult non-operation group, hospital length of stay (HLOS) was a significant risk factor associated with mortality (OR = 1.077, 95% CI: 1.004−1.155, p = 0.038). In the elderly non-operation group, obstruction was the main risk factor (OR = 4.534, 95% CI: 1.387−14.819, p = 0.012). Elderly patients experienced a 3.5-fold higher mortality than adult patients who were emergently admitted with umbilical hernia. Increasing age was a significant risk factor of mortality within all patient populations. In the adult surgical group, gangrene, Medicare, Medicaid, and self-pay were significant risk factors of mortality and female sex was a significant protective factor. In the adult non-surgical group, HLOS was the main risk factor of mortality. In the elderly population, frailty and gangrene were the main risk factors of mortality within the surgical group, and obstruction was the main risk factor for the non-surgical group.