Lower Extremity Somatosensory Evoked Potentials Predict Functional Outcomes in Complete Traumatic Cervical Spinal Cord Injury

BACKGROUND

Traumatic cervical spinal cord injury (tCSCI) is often a debilitating injury, making early prognosis important for medical and surgical planning. Currently, the best early predictors of prognosis are physical examination, imaging studies, and patient demographics. Despite these factors, patient outcomes continue to vary significantly. The purpose of this study was to evaluate the prognostic value of somatosensory evoked potentials (SSEPs) with functional outcomes in tCSCI patients.

METHODS

A retrospective study was conducted on prospectively collected data from 2 academic institutions. Patients 18 years and older who had tCSCI and underwent posterior cervical decompression and stabilization with intraoperative neuromonitoring were reviewed. The outcomes of interest were the American Spinal Injury Association (ASIA) Impairment Scale (AIS) grade and ASIA motor score at follow-up. Outcomes measures were assessed via student t-tests, chi-squared tests, and multivariable regression analysis.

RESULTS

A total of 79 patients were included. In complete injuries, detectable lower extremity SSEPs were associated with higher ASIA motor scores at follow-up (P = 0.002), greater increases in ASIA motor scores at follow-up (P = 0.009), and a greater likelihood of clinically important improvement in ASIA motor score (P = 0.024). Incomplete, AIS grade C injuries has higher rates of grade conversion (P = 0.019) and clinically important improvement in ASIA motor score (P = 0.010), compared to AIS grade A or B injuries.

CONCLUSIONS

The detection of lower extremity SSEP signals during initial surgical treatment of tCSCI is associated with greater improvement in ASIA motor scores postoperatively. The association is most applicable to patients with complete injury.

Perioperative Opioid Use in Anterior Cruciate Ligament Reconstruction Patients

Anterior cruciate ligament reconstruction (ACLR) is one of the most commonly performed outpatient orthopaedic procedures, yet there is little data about perioperative opioid prescribing practices. The purposes of this study were to quantify the perioperative opioid prescriptions filled by patients who underwent ACLR and to identify factors associated with greater postoperative opioid use. Patients who underwent ACLR at a single institution between June 2015 and May 2017 were studied using a regional prescription monitoring database to identify all preoperative and postoperative outpatient opioid prescriptions up to 2 years postoperatively. The number of morphine milligram equivalents of each opioid was calculated to determine total morphine milligram equivalents (TMEs) filled preoperatively, at discharge, and refilled postoperatively. Patients who refilled an opioid prescription postoperatively were compared with those who did not. Ninety-nine of 269 (36.8%) total patients refilled an opioid prescription postoperatively. Thirty-three patients (12.3%) required a refill after 2 weeks postoperatively, and no patients refilled after 21 months postoperatively. Fifty-seven patients (21%) received an opioid prescription in the 2 years following surgery that was unrelated to their ACL reconstruction. Increased age, higher body mass index (BMI), government insurance, current or prior tobacco use history, preoperative opioid use, and greater number of medical comorbidities were significantly associated with refilling a prescription opioid. Higher BMI and government insurance were independent predictors of refilling. Higher preoperative TMEs and surgeon were independent predictor of greater refill TMEs. In the opioid-naïve subgroup of 177 patients, only higher BMI was a predictor of refilling, and only greater comorbidities was a predictor of greater refill TMEs. The results demonstrate that preoperative opioid use was associated with postoperative opioid refills and higher refill TMEs in a dose-dependent fashion. A higher percentage of patients received an opioid prescription for reasons unrelated to the ACL reconstruction than refilled a prescription after the first 2 weeks postoperatively.

Perioperative opioid use and Press Ganey patient satisfaction scores after anterior cruciate ligament reconstruction

Background

Satisfaction measures such as Press Ganey (PG) scores are increasingly used to determine reimbursement.

Purpose

To investigate the relationship between PG satisfaction scores and perioperative opioid use in patients undergoing anterior cruciate ligament reconstruction (ACLR).

Methods

Patients undergoing ACLR were retrospectively identified. Perioperative opioid prescription data were collected using the electronic medical record.

Results

Positive correlations existed between immediate preoperative total morphine equivalents (TMEs) and PG scores. There was a negative correlation between "Pain Control" and preoperative TMEs.

Conclusion

PG scores were correlated with preoperative and intraoperative opioid administration but not postoperative opioid administration.

Predictors of met expectations two years after knee surgery

Introduction

The purpose of this study is to determine which patient factors predict two-year postoperative met expectations in a cohort of patients undergoing knee surgery. Additionally, this study aims to measure the association between met expectations and postoperative outcomes.

Methods

319 patients undergoing knee surgery at one institution were studied. Patients completed patient-reported outcome questionnaires prior to surgery and again two years postoperatively. Preoperative Expectations and postoperative Met Expectations were measured using the Musculoskeletal Outcomes and Data Evaluation Management System (MODEMS) Expectations domain.

Results

The mean Met Expectations score was significantly lower than the preoperative Expectations Score. Worse two-year Met Expectations were associated with older age, higher BMI, greater comorbidities, more previous surgeries, black race, unemployment, lower income, government insurance, Worker's Compensation, smoking, and no injury prior to surgery. Greater Met Expectations were correlated with better scores on all two-year outcome measures as well as greater improvement on most outcome measures. Race, insurance status, function, mental health, and knee pain were found to be independent predictors of Met Expectations.

Conclusion

This study identified multiple patient factors and outcome measures that were associated with Met Expectations two years after knee surgery.

Preoperative expectations and early postoperative met expectations of extremity orthopaedic surgery

BACKGROUND

Preoperative patient expectations and met expectations are likely associated with the outcome of treatment. However, there is a lack of data regarding the preoperative expectations and early postoperative met expectations of patients undergoing extremity orthopaedic surgery. The purpose of this study was to identify the predictors of early postoperative met expectations in a cohort of patients undergoing extremity orthopaedic surgery and to assess the relationship between patient expectations and patient-reported outcome (PRO) measures. We hypothesized that patients with higher preoperative expectation scores and higher postoperative met expectation scores would have better early postoperative outcomes.

METHODS

Four hundred thirty-five patients age seventeen and older who underwent extremity orthopaedic surgery at one institution were prospectively enrolled in this study. Each patient completed a preoperative questionnaire that included an assessment of demographics, pain, function, general health, treatment expectations, activity level, and Patient-Reported Outcome Measurement Information System (PROMIS) computer adaptive testing. Expectations were evaluated using the Expectations Domain of the Musculoskeletal Outcomes Data Evaluation and Management System (MODEMS) questionnaire. Patients completed a follow-up questionnaire two weeks after surgery that also assessed MODEMS met expectations and satisfaction (Surgical Satisfaction Questionnaire (SSQ-8)).

RESULTS

The mean preoperative expectation score was 86.95 ± 16.59, and the mean postoperative met expectation score was 55.02 ± 27.63 (0-100 scale with 100 representing the highest level of expectations). Greater met expectations were significantly associated with white race (p = 0.025), college degree (p = 0.011), and higher income (p = 0.002). Greater met expectations were also significantly associated with greater postoperative physical function, social satisfaction, activity level, and subjective improvement, as well as lower pain interference, joint pain, body pain, fatigue, anxiety, and depression (p < 0.01 for each). Multivariable analysis results found that less postoperative joint pain and greater postoperative social satisfaction, improvement, and physical function were all significant independent predictors of greater met expectations at two weeks postoperative (p < 0.01 for each).

CONCLUSION

Greater preoperative expectations are associated with better activity and less pain two weeks after surgery. Met expectations of extremity orthopaedic surgery were associated with postoperative physical function, social satisfaction, activity, pain, anxiety, depression, and subjective improvement. These results may have implications for preoperative counseling and risk factor modification.

Alteration in the acyl lipid composition of thylakoids induced by aging and its effect on thylakoid structure

The alteration in both the lipid composition and chlorophyll proteins obtained by sodium dodecyl sulfate-polyacrylamide gel electrophoresis of detergent solubilized thylakoids was investigated on differentially aged spinach (Spinacia oleracea L.) chloroplasts. Freshly isolated material demonstrated seven major bands upon electrophoretic fractionation. Membranes aged in vitro showed a diminution and/or a disappearance of some bands concomitant with changes in the acyl lipid composition of these membranes. The extent of these changes was influenced by the purity of the preparation. Low temperature fluorescence measurements (77K) showed that upon aging, the photochemical capacity of photosystem II decreased prior to alterations in the molecular organization of the photochemical apparatus as indicated by the energy distribution between the two photosystems.The results are discussed in terms of whether the series of changes in the acyl lipid composition upon aging is related to the variations in the electrophoretic pattern of the chlorophyll proteins.

Intracellular localization, isolation and characterization of two distinct varieties of superoxide dismutase from Neurospora crassa

1. Neurospora crassa was found to contain two distinct superoxide dismutases. 2. Most of the activity is associated with the cytosolic fraction and was shown to be the Cu/Zn-containing form of the protein. 3. Mitochondria isolated from Neurospora crassa showed two distinct superoxide dismutases: a cyanide-sensitive Cu/Zn-containing protein and a cyanide-insensitive form which probably contains manganese. 4. Localization experiments, using selective marker enzymes and digitonin fractionation, indicated that the cyanide-sensitive form is localized in the intermembrane space, whereas the cyanide-insensitive form is confined to the mitochondrial matrix space. 5. The cytosolic Cu/Zn-containing superoxide dismutase was isolated in high yields and extensively characterized by using e.p.r. spectroscopy, isoelectric focusing and analytical ultracentrifugation. 6. E.p.r. spectroscopy was used to monitor changes in the copper environment of the native protein after the addition of a number of potential inhibitors and after high-pH treatment. 7. Both of the cyanide-sensitive Cu/Zn-containing enzymes (cytosolic and mitochondrial) appeared to have identical properties which in turn were different from the cyanide-insensitive enzyme. 8. It is probable that the cyanide-insensitive enzyme was not previously detected, owing to its low amount (less than 10% of the total activity), greater lability than the cyanide-sensitive enzyme and the necessity of obtaining a mitochondrial-enriched fraction before its isolation.

Superoxide dismutase and catalase in the protection of the proton-donating systems of nitrogen fixation in the blue-green alga Anabaena cylindrica

1. Superoxide dismutase activity was present in the heterocysts and vegetative cells of Anabaena cylindrica, but was always lower in the heterocysts. 2. No qualitative differences were found in the superoxide dismutase from the two cellular types. 3. Catalase activity was also present in both cellular types. 4. Most of the NADP reductase activity, as assayed with menadione or ferredoxin as electron acceptor, was localized within the heterocysts. 5. Studies on H2 consumption showed that most of the hydrogenase activity was associated with the heterocysts. 6. The results are discussed in terms of the postulate that superoxide dismutase and catalase are involved in the protection of the proton-donating systems participating in N2 fixation and H2 metabolism of heterocysts.