Cruciate ligament reconstruction has progressed dramatically in the last 20 years. Anatomic placement of ligament substitutes has fostered rehabilitation efforts that stress immediate and full range of motion, immediate weightbearing, neuromuscular strength and coordination, and early return to athletic competition (3 months). This has placed extreme importance on secure graft fixation at the time of ligament reconstruction. Current ligament substitutes require a bony or soft tissue component to be fixed within a bone tunnel or on the periosteum at a distance from the normal ligament attachment site. Fixation devices have progressed from metal to biodegradable and from far to near-normal native ligament attachment sites. Ideally, the biomechanical properties of the entire graft construct would approach those of the native ligament and facilitate biologic incorporation of the graft. Fixation should be done at the normal anatomic attachment site of the native ligament (aperture fixation) and, over time, allow the biologic return of the histologic transition zone from ligament to fibrocartilage, to calcified fibrocartilage, to bone. The purpose of this article is to review current fixation devices and techniques in cruciate ligament surgery.

The structure and function of the anterolateral complex (ALC) of the knee has created much controversy since the 're-discovery' of the anterolateral ligament (ALL) and its proposed role in aiding control of anterolateral rotatory laxity in the anterior cruciate ligament (ACL) injured knee. A group of surgeons and researchers prominent in the field gathered to produce consensus as to the anatomy and biomechanical properties of the ALC. The evidence for and against utilisation of ALC reconstruction was also discussed, generating a number of consensus statements by following a modified Delphi process. Key points include that the ALC consists of the superficial and deep aspects of the iliotibial tract with its Kaplan fibre attachments on the distal femur, along with the ALL, a capsular structure within the anterolateral capsule. A number of structures attach to the area of the Segond fracture including the capsule-osseous layer of the iliotibial band, the ALL and the anterior arm of the short head of biceps, and hence it is not clear which is responsible for this lesion. The ALC functions to provide anterolateral rotatory stability as a secondary stabiliser to the ACL. Whilst biomechanical studies have shown that these structures play an important role in controlling stability at the time of ACL reconstruction, the optimal surgical procedure has not yet been defined clinically. Concern remains that these procedures may cause constraint of motion, yet no clinical studies have demonstrated an increased risk of osteoarthritis development. Furthermore, clinical evidence is currently lacking to support clear indications for lateral extra-articular procedures as an augmentation to ACL reconstruction. The resulting statements and scientific rationale aim to inform readers on the most current thinking and identify areas of needed basic science and clinical research to help improve patient outcomes following ACL injury and subsequent reconstruction. Level of evidence V.

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Background Mean arterial blood pressure (MAP) targets are empirically chosen during cardiopulmonary bypass (CPB). We have previously shown that near-infrared spectroscopy (NIRS) can be used clinically for monitoring cerebral blood flow autoregulation. The hypothesis of this study was that real-time autoregulation monitoring using NIRS-based methods is more accurate for delineating the MAP at the lower limit of autoregulation (LLA) during CPB than empiric determinations based on age, preoperative history, and preoperative blood pressure. Methods Two hundred thirty-two patients undergoing coronary artery bypass graft and/or valve surgery with CPB underwent transcranial Doppler monitoring of the middle cerebral arteries and NIRS monitoring. A continuous, moving Pearson's correlation coefficient was calculated between MAP and cerebral blood flow velocity, and between MAP and NIRS data to generate mean velocity index and cerebral oximeter index. When autoregulated, there is no correlation between cerebral blood flow and MAP (i.e., mean velocity and cerebral oximetry indices approach 0); when MAP is below the LLA, mean velocity and cerebral oximetry indices approach 1. The LLA was defined as the MAP where mean velocity index increased with declining MAP to ≥ 0.4. Linear regression was performed to assess the relation between preoperative systolic blood pressure, MAP, MAP in 10% decrements from baseline, and average cerebral oximetry index with MAP at the LLA. Results The MAP at the LLA was 66 mmHg (95% prediction interval, 43 to 90 mmHg) for the 225 patients in which this limit was observed. There was no relationship between preoperative MAP and the LLA (p = 0.829) after adjusting for age, gender, prior stroke, diabetes, and hypertension, but a cerebral oximetry index value of >0.5 was associated with the LLA (p=0.022). The LLA could be identified with cerebral oximetry index in 219 (94.4%) patients. The mean difference in the LLA for mean velocity index versus cerebral oximetry index was −0.2±10.2 mmHg (95%CI, −1.5 to 1.2 mmHg). Preoperative systolic blood pressure was associated with a higher LLA (p=0.046) but only for those with systolic blood pressure ≤160 mmHg. Conclusions There is a wide range of MAP at the LLA in patients during CPB making estimating this target difficult. Real-time monitoring of autoregulation with cerebral oximetry index may provide a more rational means for individualizing MAP during CPB.

Cognitive recovery after anaesthesia and surgery is a concern for older adults, their families, and caregivers. Reports of patients who were 'never the same' prompted a scientific inquiry into the nature of what patients have experienced. In June 2018, the ASA Brain Health Initiative held a summit to discuss the state of the science on perioperative cognition, and to create an implementation plan for patients and providers leveraging the current evidence. This group included representatives from the AARP (Area. This paper summarises the state of the relevant clinical science, including risk factors, identification and diagnosis, prognosis, disparities, outcomes, and treatment of perioperative neurocognitive disorders. Finally, we discuss gaps in current knowledge with suggestions for future directions and opportunities for clinical and translational projects.

Objectives To determine whether mean arterial blood pressure (MAP) excursions below the lower limit of cerebral blood flow (CBF) autoregulation during cardiopulmonary bypass (CPB) are associated with acute kidney injury (AKI) after surgery. Setting Tertiary care medical center. Patients Four hundred ten patients undergoing cardiac surgery with CPB. Design Prospective observational study. Interventions None. Measurements and Main Results Autoregulation was monitored during CPB by calculating a continuous, moving Pearson’s correlation coefficient between MAP and processed near-infrared spectroscopy signals to generate the variable cerebral oximetry index (COx). When MAP is below the lower limit of autoregulation, COx approaches 1, because CBF is pressure passive. An identifiable lower limit of autoregulation was ascertained in 348 patients. Based on the RIFLE criteria, AKI developed within 7 days of surgery in 121 (34.8%) of these patients. Although the average MAP during CPB did not differ, the MAP at the limit of autoregulation and the duration and degree to which MAP was below the autoregulation threshold (mmHg × min/hr of CPB) were both higher in patients with AKI than in those without AKI. Excursions of MAP below the lower limit of autoregulation (relative risk, 1.02, 95% confidence interval, 1.01 to 1.03, p<0.0001) and diabetes (relative risk, 1.78, 95% confidence interval, 1.27 to 2.50, p=0.001) were independently associated with for AKI. Conclusions Excursions of MAP below the limit of autoregulation and not absolute MAP are independently associated with for AKI. Monitoring COx may provide a novel method for precisely guiding MAP targets during CPB.

Objectives Optimizing blood pressure using near-infrared spectroscopy monitoring has been suggested to ensure organ perfusion during cardiac surgery. Near-infrared spectroscopy is a reliable surrogate for cerebral blood flow in clinical cerebral autoregulation monitoring and might provide an earlier warning of malperfusion than indicators of cerebral ischemia. We hypothesized that blood pressure below the limits of cerebral autoregulation during cardiopulmonary bypass would be associated with major morbidity and operative mortality after cardiac surgery. Methods Autoregulation was monitored during cardiopulmonary bypass in 450 patients undergoing coronary artery bypass grafting and/or valve surgery. A continuous, moving Pearson’s correlation coefficient was calculated between the arterial pressure and low-frequency near-infrared spectroscopy signals and displayed continuously during surgery using a laptop computer. The area under the curve of the product of the duration and magnitude of blood pressure below the limits of autoregulation was compared between patients with and without major morbidity (eg, stroke, renal failure, mechanical lung ventilation >48 hours, inotrope use >24 hours, or intra-aortic balloon pump insertion) or operative mortality. Results Of the 450 patients, 83 experienced major morbidity or operative mortality. The area under the curve of the product of the duration and magnitude of blood pressure below the limits of autoregulation was independently associated with major morbidity or operative mortality after cardiac surgery (odds ratio, 1.36; 95% confidence interval, 1.08–1.71; P = .008). Conclusions Blood pressure management during cardiopulmonary bypass using physiologic endpoints such as cerebral autoregulation monitoring might provide a method of optimizing organ perfusion and improving patient outcomes from cardiac surgery.

Background Although spine surgery is frequent in older adults, the incidence, risk factors, and consequences of delirium in this population have not been well characterized. This is important since spine surgery is increasingly common, pain is a prominent symptom, and postoperative delirium may be preventable. Methods We enrolled 89 adults >70 y/o undergoing spine surgery in a prospective observational study. Postoperative delirium and delirium severity were assessed using validated methods, including the Confusion Assessment Method (CAM), CAM-ICU, Delirium Rating Scale-Revised-98, and chart review. Hospital-based outcomes were obtained from the medical record, and hospital charges from data reported to the state. Results Thirty-six patients (40.5%) developed delirium after spine surgery, with 17 (47.2%) having purely hypoactive features. Independent predictors of delirium were lower baseline cognition, higher average baseline pain, more IV fluid administered, and baseline anti-depressant medication. In adjusted models, the development of delirium was independently associated with increased quintile of length of stay (OR 3.66; 95%CI 1.48–9.04; p=0.005), increased quintile of hospital charges (OR 3.49; 95%CI 1.35–9.00; p=0.01), and decreased odds of discharge to home (OR 0.22; 95%CI 0.07–0.69; p=0.009). The severity of delirium was associated with increased quintile of hospital charges and decreased odds of discharge to home. Conclusion Delirium is common after spine surgery in older adults, and baseline pain is an independent risk factor. Delirium is associated with increased length of stay, increased charges, and decreased odds of discharge to home. Thus, prevention of delirium after spine surgery may represent an important quality improvement goal.