Becker’s has reported on four studies since Aug. 23 that spine and orthopedic surgeons should know.
1. Taking aspirin after a joint replacement surgery could increase the risk of blood clots, according to a study published Aug. 23 in the Journal of the American Medical Association.
2. A study published in The Spine Journal concluded that patient improvement in neck pain was greater than improvement in arm pain following cervical disc replacements.
3. A study published in the July 2022 edition of Operative Neurosurgery supports the long-term use of Premia Spine’s Tops spinal joint replacement system.
4. Pacira BioSciences’ Exparel drug was found to be effective in treating pain after total knee replacements, according to a study.
The primary disadvantage of the total joint replacement (TJR) treatment is the critical loss of skeletal muscle attached to metal joint prostheses, resulting in the formation of fibrous scar tissue, ultimately leading to motor dysfunction. Consequently, tissue engineering technology may come to the rescue in addressing this issue.
Study: Improved Muscle Regeneration into a Joint Prosthesis with Mechano-Growth Factor Loaded within Mesoporous Silica Combined with Carbon Nanotubes on a Porous Titanium Alloy. Image Credit: gowithstock/Shutterstock.com
An article published in the journal ACS Nano demonstrated the fabrication of a two-layered mechano-growth factor (MGF) carrier, an alternative isoform of insulin-like growth factor-1 (IGF-1) expressed in response to mechanical stimulation.
The two-layered MGF carrier was made of a porous titanium alloy scaffold coated with mesoporous silica nanoparticles (MSNs) and carbon nanotubes (CNTs) via electrophoretic deposition (EPD). The two-layered coating exhibited a nanostructured topology with excellent MGF loading and extended-release performance via covalent bonding.
In vivo studies on the fabricated scaffolds revealed that they preferentially promoted muscle growth than fibrotic tissue into titanium alloy structure and improved the muscle-derived mechanical properties, immunomodulation, and migration of satellite cells.
Thus, the fabricated MGF-loaded MSN and CNT-coated titanium alloy scaffolds were presented as a robust platform to restore the motor function of implanted joints like the natural joint by periprosthetic muscle regeneration.
Disadvantages of TJR Treatment and Titanium alloy in Prostheses
TJR treatment is popularly applied to replace natural joints with prostheses through arthroplasty surgery by orthopedic surgeons. However, in vivo degradation results in a shorter lifetime for these artificial joints compared to natural synovial joints. This occurs primarily because of the higher wear rates associated with artificial implant materials and the consequent adverse biological effect of the generated wear debris on bone mass/density and implant fixation.
Further, when compared to the initial TJR surgery, revision surgery of an implant is challenging, has a lower success rate, may induce additional damage to the surrounding tissues, and increases health care costs by one-third. Thus, a paradigm shift to periprosthetic muscle regeneration can increase the lifetime of prostheses.
Motor dysfunction due to the connection loss between prostheses and muscle tissue is a common complaint of patients after TJR. Thus, the periprosthetic muscle regeneration into prostheses can help to regain normal joint motor function.
Titanium alloy is considered the best solution to address the above concerns and can match both the aesthetic and the functional requirements guaranteed by the implant. Titanium alloy exhibits low values of Young’s modulus and offers a wide span of properties.
Improved Periprosthetic Muscle Regeneration
MSNs have adjustable pore diameter, high surface area, large pore volume, and excellent biocompatibility and hence stand as promising candidates to deliver therapeutic agents. However, a few studies based on MSN-coated porous titanium alloy scaffolds mentioned the brittleness of MSNs. On the other hand, CNTs have high strength and elastic modulus compared to other reinforcement fibers.
In the present work, CNTs were incorporated into MSNs as reinforcement fibers to relieve the strain between titanium alloy and MSNs. Integrating CNTs and MSNs into titanium alloy improved biomechanical behavior and imparted a sufficient biomolecule-loading capacity.
In the present work, a three-dimensionally (3D) printed porous titanium alloy was coated with a CNT-MSN layer via the EPD method, followed by loading of MGF into MSNs via covalent bonding with the help of 1-ethyl-3-(3- dimethylaminopropyl) carbodiimide hydrochloride (EDC) and N-hydroxysuccinimide (NHS). This helped achieve a long-term, slow release in prepared scaffolds.
Furthermore, the periprosthetic muscle regeneration into the prepared [email protected] coated titanium alloy scaffold was evaluated by conducting in vivo and in vitro studies. The results revealed an increased expression of myogenic genes and proteins, enhancing myoblast differentiation without biotoxicity, leading to the formation of myotubes and skeletal muscle fibers, indicating the potential of a prepared scaffold for periprosthetic muscle regeneration.
Additionally, the [email protected] coated titanium alloy scaffold activated the biological mechanism that induced the myoblast differentiation through the Akt/mTOR signaling pathway, indicated by the expression of Akt/mTOR signal-related proteins. Thus, proving the potential of MGF in serving as a local cell growth factor.
Conclusion
In summary, the two-layered MGF carrier that maintained a long-term release was composed of an inner CNT buffer layer and an outer [email protected] functional layer in the porous titanium alloy scaffold and was deposited using the EPD method.
The designed [email protected] porous titanium alloy scaffold enhanced the myoblast differentiation compared to the traditional prosthesis, without cytotoxicity, by increasing the expression of myogenic proteins and genes, forming myotubes and skeletal muscle fibers in vivo and in vitro.
The periprosthetic muscle regeneration into prostheses is needed to regain normal joint motor function. The scaffold fabricated in the present work was presented as a promising nanomaterial-based platform for periprosthetic muscle tissue regeneration into prostheses during recovery to regain normal joint motor function.
Examining the biomechanism of myogenesis gave insights into the ability of titanium alloy based on the [email protected] scaffold in activating the Akt/mTOR signaling pathway, promoting myoblast differentiation.
Reference
Wei, X et al. (2022). Improved Muscle Regeneration into a Joint Prosthesis with Mechano-Growth Factor Loaded within Mesoporous Silica Combined with Carbon Nanotubes on a Porous Titanium Alloy. ACS Nano. https://pubs.acs.org/doi/10.1021/acsnano.2c04591
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Intraosseous (IO) infusion of medication during surgery has been shown to be a new and effective way to manage pain in patients undergoing total knee arthroplasty (TKA), according to a recent study.
To determine the safety and efficacy of injecting pain medication directly into the tibia during surgery and the impact that this method may have on pain levels and time spent in the hospital, the researchers performed a double-blind, randomized controlled study examining patients undergoing TKA (n = 48). The patients were divided into 2 groups: the experimental group (n = 24) who received both an IO antibiotic injection and 10 mg of morphine, and the control group (n = 24) who received only a standard IO injection of antibiotics.
The researchers assessed pain, nausea, and opioid use up to 14 days post-surgery for all patients. Additionally, the researchers examined morphine and interleukin-6 serum levels in a subgroup of 20 patients 10 hours post-surgery.
The researchers used the Visual Analog Scale to determine the level of pain each patient had postoperatively. Patients in the experimental group had a lower pain score at 1-, 2-, 3-, and 5-hours post-surgery (P = .0032, P = .005, P = .020, P = .10) when compared with the control group. The decrease in pain continued for postoperative day 1 (40% reduction, P = .01), day 2 (49% reduction, P = .036), day 8 (38% reduction, P = .025), and day 9 (33% reduction, P = .041).
Furthermore, the researchers saw a lower opioid consumption within the first 48 hours and the 2nd-week post-surgery among the experimental group when compared with the control group (P < .05). Serum morphine levels in were significantly less in the experimental group than in the control group 10 hours after IO injection (P = .049). The experimental group also has significant improvement (P < .05) in the Knee Injury and Osteoarthritis Outcome Score for Joint Replacement scores at 2- and 8-weeks post-surgery.
Overall, the experimental group showed significant improvement and outcome post-surgery.
“IO morphine combined with a standard antibiotic solution demonstrates superior postoperative pain relief immediately and up to 2 weeks,” the researchers concluded. “IO morphine is a safe and effective method to lessen postoperative pain in TKA patients.”
—Jessica Ganga
Reference:
Brozovich AA, Incavo SJ, Lambert BS, et al. Intraosseous morphine decreases postoperative pain and pain medication use in total knee arthroplasty: a double-blind, randomized controlled trial. J Arthroplasty. 2022;37(6):139-146. doi:10.1016/j.arth.2021.10.009.
Scientists from ExplantLab have identified a genotype that is associated with joint replacement failure in some patients. Based on these findings, the scientists developed a machine-learning algorithm called Orthotype, which uses a patient’s genotype and other factors to accurately predict the outcome of joint replacement surgery.
More than five million joint replacements are performed globally each year. Although most patients are satisfied with the results of their surgery, a significant number of joint replacements fail early, following adverse immune responses.
One of the most popular implant materials used in joint replacements is cobalt chrome (CoCr). When small particles from CoCr joints are released into the blood, it can lead to an immune response that results in pain and joint failure in some patients.
“Essentially, the immune system attacks the implant in a process similar to how a patient rejects an organ transplant,” explained David Langton, PhD, director of ExplantLab. “How quickly this happens is variable and unpredictable, but it appears to be dependent on the type of material, the amount of wear debris released, and other patient-specific factors.”
One of those patient-specific factors is their genes. The HLA genes play a central role in immune function, and Langton and his colleagues determined that patients with certain HLA genotypes are likely to develop responses to CoCr-containing implants. Their results were published in Communications Medicine.
Taking the research one step further, ExplantLab, working with bioengineers, medical staff, and patients from collaborating institutions, developed a machine-learning algorithm called Orthotype, which uses a patient’s genotype to provide a risk profile of that patient developing hypersensitivity to CoCr. Orthotype was developed and validated from the results from 606 patients implanted with metal hip replacements and resurfacings, each of whom had been followed for a mean duration of ten years.
This could herald a new era where it will become routine for patients to undergo genetic testing prior to receiving medical implants. Orthotype will identify patients more likely to have a reaction to a joint replacement made of CoCr components, helping surgeons select an implant based on the manufactured material most suited to the individual patient.
“This represents a significant advance in orthopedic care for patients,” said Langton, “with potentially significant financial repercussions for global healthcare systems, through the avoidance of repeat surgery.”
As populations around the world grow older and heavier, joint replacements are more common than ever. The number of joint replacement surgeries carried out globally is forecast to double over the next two decades.
Football is a high-contact sport made most popular in the United States. Because of the physical nature of the sport, injuries are a common occurrence. In addition, due to the level of physicality involved, certain injuries are more common than others.
What follows will be a discussion of the most common football-related injuries, likely causes of each, and tips on how to prevent them. While not all injuries can be prevented, there are proactive steps that can be taken to ensure that the body is the most prepared for playing football.
Most Common Football-Related Injuries
Hundreds of thousands of young people and adults visit their doctors, medical clinics, and emergency centers for football-related injuries every year.
Additionally, in the first four weeks of the 2020-2021 NFL season, a reported 3,025 injuries were sustained. A typical NFL season spans 18 weeks, not including the postseason time frame.
Lastly, several lawsuits regarding sport-induced concussions in professional football players have reached a point of national news in recent years due to the prevalence and general concern for players’ long-term health.
While football does use protective equipment, it’s still a fast-paced, high-intensity, impact-based sport. Injuries, both minor and traumatic, are going to occur.
Like many sports, there are a variety of causes of different injuries at different severity levels. These include but are not limited to overtraining, lack of recovery, and in-game incidental contact. The most common injuries in football are those of traumatic severity, such as concussions and muscular or ligament tears.
The following are the most common football-related injuries:
Other notable injuries include joint dislocations and separations, hamstring & quadriceps tears, rotator cuff injuries, shin splints, and ulnar collateral ligament (UCL) injury seen commonly in quarterbacks.
Concussions
Concussions are one of the most common injuries in football and contact sports in general. While there is a naive perspective surrounding concussions, especially in sports, they are serious injuries in the category of traumatic brain injury.
Upon impact, the brain shakes back and forth within the skull. The ultimate result of this brain movement within the skull is brain cell damage, which can sometimes be extensive.
According to the NSC, being struck by another person or object is the leading cause of unintentional injury for teens and young adults ages 15 to 24. Further, it’s estimated that 1.6 million to 3.8 million athletes annually suffer a concussion. While not all concussions are related to football, it does happen to be one of the most prevalent injuries seen in football players.
Traumatic Knee Injuries
Traumatic knee injuries include but are not limited to Anterior Cruciate Ligament (ACL), Posterior Cruciate Ligament (PCL), Medial Collateral Ligament (MCL), and meniscus tears. The ACL, for example, is crucial for providing knee stability and strength, a function not only necessary for sport but everyday life.
These career-ending or career-altering ligament injuries are most often the result of rapid changes in motion during play, impact, or faulty movement (i.e., a trip, fall, or twist).
Fractures
Fractures or broken bones are a common occurrence in many sports, football included. The most common locations of a fracture in football are the finger, hand, wrist, and foot.
The causes of a fracture are several. Depending on the location, a fracture can be secondary to overuse, impact, or excessive movement of a given limb.
Tendonitis
The most common form of tendonitis in football is Achilles tendonitis, though it can develop in other regions of the body, such as the elbow. Tendonitis typically results in stiffness, aches, and painful movement. Depending on the severity level, tendonitis can keep a player out of action for some time.
Sometimes tendonitis can develop into a more significant injury like a tendon tear or rupture. For example, a common injury in football is an Achilles rupture.
Sprains, Strains, Aches, & Pains
This category of injury, though less severe, is the most common occurrence in all sports, not just exclusive to football. This is because sport requires such physical demand that the body is put under a lot of stress.
It’s almost inevitable then, depending on the frequency, intensity, and level of play, that these minor impairments will occur over time.
Injuries such as ankle sprains, rotator cuff strains, hamstring strains, and lower back strains are all very common in football. The good news is that these types of minor injuries can often be prevented.
If a carefree attitude is maintained towards preventative behavior, these injuries can lead to a much more severe problem, such as a tear, rupture, or fractured bone.
Injury Prevention Tips for Football Players
Prevention is the best medicine for any disease, condition, illness, or injury. Luckily, many football-related injuries, and sports-related injuries in general, can be prevented.
In fact, According to the U.S. Consumer Product Safety Commission, more than 920,000 under the age of 18 were treated in medical clinics for football-related injuries, most of which could have been prevented. It is also true that unavoidable accidental injuries occur with any sport, even with the best preventative measures.
The following are the most common and effective preventative measures athletes can take to prevent, or at the very least, reduce the risk of such injuries occurring:
Stretching
Adequate Hydration
Avoiding overtraining
Implementing a warm-up and cooldown regimen, both during games, training sessions, practices, and workouts
Performing adaptive strength training exercises
Following prehab protocols (i.e., preventative rehabilitation exercises)
Learning proper tackling techniques
Ensuring that your equipment fits properly
Having regular check-ups with your doctor, physiotherapist, and trainer
The most common ways for injuries to occur outside of accidental happenings or traumatic impacts are a lack of hydration, tightness & stiffness due to lack of stretching, overtraining, and taking part in activity when you’re not properly warmed up.
All of the above are surefire ways to increase your risk of injury. Combatting them is the recipe for prevention.
Final Thoughts
The speed at which one tends to an injury has a direct correlation to the quality and speed of healing. In contrast, ignoring symptoms, especially of injuries such as concussions, can lead to severe complications.
One of the most important things is to seek timely care. If symptoms of an injury persist, additional medical attention should be obtained.
Following preventative tips, as discussed, can significantly reduce the risk of football-related injuries for the athlete.
Total hip replacement is one of the most common non-emergency surgeries. The number of yearly hip replacements performed in the United States is expected to rise to 635,000 by the year 2030 due to the aging population.
Hip replacements are commonly used to treat conditions like arthritis and hip fractures that cause pain and stiffness. The risk of serious complications following a hip replacement is generally low, but all surgeries come with some risk.
Heart attack and other serious cardiovascular complications are possible complications of joint replacement surgeries. The risk of having a heart attack is highest in people with a history of cardiovascular disease and becomes higher with advancing age.
Read on to learn more about the link between hip replacement surgery and heart attacks, including how common heart attacks are after hip surgery, risk factors, and things you can do to prevent them.
A total hip replacement is one of the most successful orthopedic surgeries, with more than a 95 percent survival rate 10 years after the procedure. The majority of hip replacements are performed on people between the ages of 60 to 80.
The single largest cause of death is major adverse cardiac events (MACE), which mostly includes heart attacks. Improvements in surgical techniques and preoperative screening have led to a significant decline in postsurgery death.
The reported 30-day incidence of heart attack ranges from 0.3 to 0.9 percent after total knee or hip replacement.
Why does hip replacement surgery increase the risk of a heart attack?
It’s not exactly clear why your risk of having a heart attack increases after major surgery, but various factors are likely at play.
Some events during surgery may increase stress on your heart. These include:
Inflammation caused during the repair process can increase your blood’s chances of clotting, which can increase your risk of heart problems. Increased heart rate and elevation in blood pressure can put stress on your coronary artery.
With orthopedic surgery, there’s also a risk of developing a fat embolism or cement embolism. That’s when fat or cement from the joint replacement gets released into the bloodstream, causing a blockage or clot. This can cause serious problems with your heart and lungs.
Changes in medications before the surgery, like discontinuing low dose aspirin, may contribute as well.
How common are heart attacks after surgery?
About 3 percent of people undergoing major surgery experience a heart attack during the procedure. Complications become more common with age and in people with a previous history of cardiovascular disease or other risk factors for heart disease.
One in 5 people over 65 or over 45 with a history of cardiovascular disease develop one or more MACE within a year of non-cardiac surgery.
How long is the risk elevated?
Your risk of developing a heart attack remains elevated in the period directly after your surgery, especially in the first week.
In a large 2016 study, researchers found the risk of heart attack became insignificant 1 month after total hip replacement.
Other studies have found that the risk of heart attack remains slightly elevated in the 4 to 6 weeks after hip replacement surgery.
While your risk of a heart attack may decrease after a few weeks, you should still be aware of some other risks. Decreased mobility after hip surgery increases your risk of a blood clot and deep vein thrombosis. This risk will likely persist until you’re active again.
Risk after hip replacement compared to other joint replacements
In a 2021 study, researchers investigated the rates of heart attack among 322,585 people who received spinal fusion or joint replacements. The researchers found that the risk of heart attack was generally higher in people receiving spinal fusion and lower in people receiving knee or hip replacements.
There’s still a limited amount of evidence about how to reduce your chances of a heart attack before surgery. It’s critical to communicate with your doctor ahead of time to evaluate your risk of complications and develop a plan to minimize your chances of developing them.
In evaluating your risk prior to surgery, your doctor will consider several factors, including:
age
overall health and underlying conditions
cardiovascular health
respiratory health
blood pressure
complete blood count
You may undergo several tests as part of the assessment, including:
physical exam
echocardiogram
electrocardiogram
chest X-ray
blood and urine tests
Your doctor may recommend taking medications like statins or beta-blockers leading into your surgery. They may also tell you to reduce or quit smoking and drinking.
Online tools are available to help you assess your risk, but you should always consult with your doctor.
Doctors don’t usually recommend a hip replacement unless your hip is worn to the point it doesn’t respond to physical therapy or steroid injections. It’s almost always an elective surgery. That means it’s not mandatory but performed to improve function and reduce pain.
A promising but developing alternative to a hip replacement for treating osteoarthritis is stem cell injections. These injections contain stem cells that can become cartilage, muscle, or bone. It’s thought that they could help regenerate lost cartilage in your hip.
One small 2018 study found promising results among five people with osteoarthritis. The people in the study experienced an average improvement of 72.4 percent in resting and active pain.
Some conditions that can cause hip pain, like autoimmune arthritis and osteoporosis, are associated with an increased risk of developing a heart attack. But research is yet to show that the conditions are responsible for the higher risk.
Research has found a link between cardiovascular disease and inflammatory forms of arthritis like rheumatoid arthritis, ankylosing spondylitis, and psoriatic arthritis. These conditions cause inflammation throughout your body that may be associated with an increased risk of developing a heart attack.
A 2016 review of studies found that heart disease was 24 percent more common in people with osteoarthritis than in people in the general population.
Studies that look at the prevalence of diseases in large populations have found an observational link between osteoporosis and cardiovascular disease, partly because of shared risk factors like aging.
Researchers have found that the risk of heart attack increases after having a hip replacement. The risk seems to be highest in the month, and particularly in the week, following surgery.
Heart attacks and other surgical complications that affect the heart become more common with advanced age. They’re also more common in people with a history of cardiovascular disease.
It’s important to talk with your doctor before your surgery to evaluate your risk of complications and develop a plan to minimize your risk.
The American College of Rheumatology (ACR)/American Association of Hip and Knee Surgeons (AAHKS) has published guidance regarding perioperative management of antirheumatic medication in patients with rheumatic diseases undergoing elective total hip or total knee arthroplasty.
The American College of Rheumatology (ACR)/American Association of Hip and Knee Surgeons (AAHKS) has published guidance regarding the management of antirheumatic medication in patients with rheumatic diseases undergoing elective total hip or total knee arthroplasty, with emphasis placed on perioperative use of disease-modifying antirheumatic drugs (DMARDs) and glucocorticoids (GCs). The last guideline update was published in 2017.
“Advances in antirheumatic therapy have led to remarkable improvements in treatment and quality of life for people with rheumatic musculoskeletal diseases (RMDs); however, total hip arthroplasty (THA) and total knee arthroplasty (TKA) remain a mainstay of treatment among RMD patients with advanced symptomatic joint damage, most frequently those with inflammatory arthritis (IA), including spondylarthritis (SpA), rheumatoid arthritis (RA), or psoriatic arthritis (PsA), and those with systemic lupus erythematosus (SLE),” investigators stated.
Top Insights:
Patients with RA, PsA, SLE, juvenile idiopathic arthritis (JIA), and ankylosing spondyloarthritis (AS) who are undergoing elective THA or TKA: continuing the usual DMARDs through surgery is conditionally recommended for methotrexate, leflunomide, hydroxychloroquine, sulfasalazine, and/or apremilast.
Patients with RA, PsA, JIA, and AS who are undergoing elective THA or TKA: withholding all biologics prior to surgery and planning surgery after the next dose is conditionally recommended.
Patients with RA, PsA, JIA, and AS who are undergoing THA or TKA: withholding tofacitinib, upadacitinib, and baricitinib for 3 or more days prior to surgery is conditionally recommended.
Patients with SLE who are interested in THA or TKA: continuing the usual dose of mycophenolate mofetil, cyclosporine, mizoribine, azathioprine, mycophenolic acid, or tacrolimus, anifrolumab, and voclosporin is conditionally recommended.
Patients with severe SLE undergoing THA or TKA: planning surgery in the last month of the dosing cycle of rituximab and continuing belimumab treatment is conditionally recommended.
Patients with SLE (not severe) undergoing THA or TKA: withholding the current dose of mizoribine, cyclosporine, azathioprine, mycophenolic acid, mycophenolate mofetil, or tacrolimus 1 week before surgery is conditionally recommended.
Patients with SLE (not severe) undergoing THA or TKA: withholding the usual dose of rituximab and belimumab prior to surgery is conditionally recommended.
Patients with severe SLE undergoing THA or TKA: continuing belimumab and planning surgery in the last month of the dosing cycle of rituximab is conditionally recommended.
Patients with RA, PsA, AS, and SLE who had antirheumatic therapy withheld prior to undergoing THA or TKA: therapy should be restarted once wound begins to heal, there is no significant swelling, erythema, or drainage, sutures and/or staples are out, and there is no nonsurgical site infection. This occurs roughly 2 weeks after surgery and is conditionally recommended.
Patients with RA, AS, PsA, and SLE undergoing THA or TKA receiving GCs: continuing current dose of GCs instead of administering supraphysiologic doses of GCs on the day of surgery is conditionally recommended.
According to data from China’s seventh census in 2020, the 60-year-old population has reached 264 million, accounting for 18.7% of the total population; of which 190 million are 65-year-old, accounting for 13.5% of the total population, and have begun to enter the “aging society”. Concomitantly, the periarticular fragility fracture of the hip, a common serious injury, has significantly increased in incidence.1 Hip fractures are recognized as a major threat to older adults, with nearly one-third of patients dying within a year of a hip fracture, and about 50% of survivors unable to return to their pre-fracture functional status.1,2 Patients with hip fractures experience a variety of complications, including frailty.3 And frailty is a predisposing factor for falls and other adverse events, including organ decline, emergency hospitalization, nursing home admission, and death.4 Moreover, frail patients who are already in poor health will become even frailer due to pain, mobility problems and inability to take care of themselves.5 This creates a bad vicious circle.
Regaining mobility after surgery is a top priority in the treatment of hip fractures in elderly patients. However, the choice of anesthesia for elderly hip fracture surgery remains controversial.6 Previous studies have shown that spinal anesthesia does not provide better outcomes after surgery for elderly patients with hip fractures.7,8 Whereas, there are also many studies support spinal anesthesia as the advantages of shortened hospital stay, higher patient satisfaction, shorter anesthesia recovery time, and reduced postoperative opioid consumption.9–11 In addition, spinal anesthesia has the advantages of fast onset, complete block, and no impact on respiratory function,12 which can be widely used in elderly hip fracture surgery. In fact, with the development of ultrasound-guided intraspinal puncture technology, the success rate of intraspinal puncture including spinal anesthesia has significantly increased,13 which may further improve the satisfaction of spinal anesthesia.
At present, the medication and dosage of spinal anesthesia for elderly patients are basically determined by anesthesiologists based on experience, and the dosage of the medication directly affects the patient’s anesthesia effect, hemodynamics, and further affects the prognosis. In this study, 50% and 95% effective doses of ropivacaine in spinal anesthesia (ED50 and ED95) in elderly patients with hip fracture surgery were determined by a modified sequential design. At the same time, the prediction formula of the individual optimal dose is provided to guide the dose selection of ropivacaine in elderly patients with hip surgery and spinal anesthesia in clinical work.
Materials and Methods
Study Design
This is a prospective, modified up-down sequential allocation study, which was conducted in the Department of Anesthesiology of the First Affiliated Hospital of the University of Science and Technology of China from June 2021 to March 2022, and passed the ethics review of the hospital ethics committee (2021KY113), and completed the registration in the China Clinical Trial Registration Center (ChiCTR2100046982). All study participants read and signed informed consent forms. This trial was conducted in accordance with the Declaration of Helsinki.
Eligibility Criteria
The inclusion criteria included (1) ASA classification II–IV; (2) Age ≥ 65 years old; (3) Elective hip fracture surgery (included femoral neck, femoral head, intertrochanteric or subtrochanteric fractures); (4) Sign the informed consent. Exclusion criteria included (1) Administered sedative and analgesic drugs within 3 hours before surgery; (2) Severe dementia; (3) Have uncontrolled neurological or psychiatric diseases; (4) Severe multiple injuries; (5) Contraindications to spinal anesthesia; (6) Participated in other drug trials within three months.
Anesthesia Procedures
Patients fasted for 8 hours before surgery. After entering the room, a “Venturi” mask with an oxygen flow of 2 L/min was used to inhale oxygen, open the venous access, connect the monitor, and continuously monitor the electrocardiogram (ECG), invasive blood pressure (IBP), pulse oxygen saturation (SpO2) and heart rate (HR). The anesthesia method is combined spinal-epidural anesthesia, the puncture is performed after ultrasound-guided positioning,14 the puncture point is L2-3, 2% lidocaine is selected as the local infiltration anesthesia, and 0.5% ropivacaine diluted with 10% glucose solution was used for spinal anesthesia. The patient is placed in a lateral recumbent position (the affected side is down), and spinal anesthesia is performed first. After the cerebrospinal fluid is confirmed to be smooth, 0.5% ropivacaine is given in about 30 seconds. Then an epidural catheter of 3–5 cm is indwelled in the epidural space. After ropivacaine injection, the lateral decubitus position was maintained for 15min to achieve unilateral block.15 Intraoperatively, additional 1% lidocaine should be added to the epidural space as needed, at the discretion of the anesthesiologist. The epidural catheter was removed after surgery.
Study Interventions
The dose of ropivacaine received by each patient in stage I was determined by a sequential method. Specifically, the initial dose was set at 7.5 mg. When the anesthesia effect of the previous patient was satisfactory, the dose of the next patient was reduced by 0.5 mg; when the anesthesia effect of the previous patient was unsatisfactory, the dose of the next patient was increased by 0.5 mg. In addition, considering the clear effect of height on the dose of spinal anesthesia, the dose should be further corrected by reference to height: for every 10cm increase or decrease in height, the dose should be increased or decreased by 0.5mg.
Definition of Satisfactory Anesthesia: (1) Anesthesia plane (assessed by acupuncture): higher than T10, lower than T6; (2) Pain-free operation within the first hour of surgery.
After the establishment of the optimal dose formula, the validation cohort was included in stage II. Spinal anesthesia was performed using the ropivacaine dose provided by the formula to evaluate the effectiveness of the formula to guide clinical ropivacaine dose selection and the success rate of meeting surgical needs.
Sample Size Calculation
The logistic regression model of this study plans to screen independent variables such as age, gender, height, weight, ASA classification, hemoglobin, white blood cells, red blood cells, and C-reactive protein. The calculation is based on the Events Per Variable principle,16 that is, the sample size is the independent Variable expected to be included multiplied by 10. Furthermore, considering the 20% dropout rate, 114 cases were finally included in the stage I of this study. In stage II, another 30 cases were included to verify the formula. A total of 144 patients.
Statistical Analysis
For numeric variables, the Shapiro-Wilk test was used to verify normality. Normally distributed variables are expressed as the mean (standard deviation), and abnormally distributed variables are expressed using the median (interquartile range). Categorical variables are expressed as numbers (percentages). Independent two-sample t-tests were used to compare normally distributed variables. Abnormally distributed variables were compared using the Mann-Whitney U test. Categorical variables were analyzed using the χ2 test or Fisher’s exact test. Probit regression was used to calculate ED50, ED95 and their 95% confidence interval (CI). Logistic regression was used to screen variables, and odds ratio (OR) was used to describe the variables included in univariate and multivariate regression models. Meanwhile, nomogram is established, and C-index evaluates its predictive ability. For patients who meet satisfactory anesthesia, a multiple linear regression model is used to establish a dose prediction equation. Data were analyzed using SPSS (version 24.0; SPSS Inc., IBM, Chicago, IL, USA). All statistical tests were two-tailed, and a P-value less than 0.05 was defined as statistically significant.
Results
Overall, a total of 180 patients were screened in this study between June 2021 and April 2022. Among them, in stage I, 15 patients refused to participate, 14 patients did not meet the criteria for admission, and 2 patients were unsuccessful in spinal anesthesia; In stage II, 1 patient refused to participate, and 4 patients did not meet the criteria for admission. A total of 144 patients completed the study, 114 in stage I and 30 in stage II. The complete selection flow chart of subjects in this study is shown in Figure 1. Baseline characteristics such as demographics and surgical information are shown in Table 1.
Table 1 Baseline Characteristics
Figure 1 Flow chart of the study.
ED50 (CI) and ED95 (CI)
According to the calculation results of Probit regression, the ED50 and ED95 of ropivacaine for spinal anesthesia of elderly hip fracture were 7.036 mg (95%CI 6.549–7.585 mg) and 8.709 mg (95%CI 7.902–14.275 mg), respectively. Goodness-of-fit test of the model P=0.108 > 0.05. The specific dose and the corresponding number of cases are shown in Table 2.
Table 2 Dose and Corresponding Number of Cases
Variable Filtering and Nomogram
Nine independent variables were included in this study and entered into logistic regression, including age, gender, height, weight, ASA classification, hemoglobin, white blood cells, red blood cells, and C-reactive protein. Group comparisons are made according to whether satisfactory anesthesia is achieved. Comprehensive consideration of univariate analysis results and clinical practice, and finally screen out age, gender, height, and weight into the model. Crude and adjusted OR are shown in Table 3. It should be explained that the OR value failed to reflect the correlation between height and anesthesia effect because the sequential plan was modified by using height in this study.
Table 3 Multivariate Logistic Regression Model
Additionally to that, we visualized the logistic regression model using the nomogram constructed by the factors described above (Figure 2). Using C-index to evaluate the discrimination of the nomogram, C-index=0.847 (95%CI 0.774–0.92), suggesting good prediction accuracy. The nomogram model was internally verified by Bootstrap repeated 1000 times sampling method, and the calibration curve of the prediction model was obtained (Figure 3), which showed that the prediction model was in good consistency with the actual observed results.
Figure 2 Nomogram to predict probability of satisfactory anesthesia.
Figure 3 Calibration curve for nomogram.
Formula for Predicting the Optimal Dose
According to the definition of satisfactory anesthesia in this study, there were 58 patients with appropriate anesthesia plane and satisfactory analgesic effect within the first hour of surgery. Based on this, the multiple linear regression model was used to incorporate age, gender, height and weight into the model as independent variables, and the following formula can be calculated: Dose(mg) = -1.39 + age(year)*0.011 – gender(male = 1; female = 0)*0.249 + height(cm)*0.047 + weight(kg)*0.005
This calculation equation has statistical significance, F=5.691, P=0.001<0.05, indicating that there is a linear correlation between the dependent variable and the independent variable. Correlation coefficient R=0.548, determination coefficient R2=0.3.
Verification of Efficacy and Safety of the Formula
The stage II of this study included 30 patients, and the same anesthesia protocol was implemented as the stage I. The ropivacaine dose was provided by the prediction equation established in stage I. Finally, the anesthesia plane of 1 patient was below T10, 1 patient felt pain during skin incision, and the other 1 patient were satisfied with analgesia at the beginning of the operation, but the duration was less than 1 hour. The anesthesia plane of the 27 patients was suitable and could provide a completely satisfactory anesthesia effect within the first hour of surgery, indicating that the formula had an effective rate of 90%. Namely, this predictive formula can guide clinical ropivacaine dose selection to a considerable extent.
Perioperative Events
The perioperative-related adverse events in this study were mainly hemodynamic changes, including hypertension and hypotension after spinal anesthesia. In stage I, 20 patients had hypotension and 11 patients had hypertension. The cases of hypotension and hypertension in stage II were both 3. It should be noted that there was no significant and uncorrectable hypotension during the trial. The occurrence of hypertension may be related to the nervousness of patients during the operation. The number of patients with inappropriate anesthesia plane or insufficient analgesia within the first hour of surgery according to the definition of satisfactory anesthesia is shown in Table 4.
Table 4 Perioperative Events
In stage I, after surgery, 99 patients (86.84%) were directly transferred to the ward, 9 (7.89%) were transferred to PACU, and 6 (5.26%) were transferred to ICU. In the stage II, after surgery, 28 patients (93.33%) were directly transferred to the ward, 2 (6.67%) were transferred to PACU, and none were transferred to the ICU.
Discussion
In this prospective, modified up-down sequential allocation study, we first calculated the ED50 and ED95 of ropivacaine for spinal anesthesia in the elderly with hip fractures, with specific values of 7.036 mg and 8.709 mg, respectively. After that, by screening the factors affecting the anesthetic effect, a more intuitive nomogram for predicting satisfactory anesthesia was established. The calculation formula for predicting the optimal dose of ropivacaine is then provided directly through the multiple linear regression model, and the factors included in the regression model included age, gender, height, and weight. After that, in stage II, the ropivacaine dose provided by the formula was used for spinal anesthesia, and the success rate was 90%. To our knowledge, this study is the first to provide a formula for calculating the optimal dose of ropivacaine for elderly hip fracture surgery.
Mei et al showed that the ED50 and ED95 of hyperbaric ropivacaine for cesarean section were 11mg and 15mg,17 and the sequential study of Lv et al showed that the ED50 of hyperbaric ropivacaine for cesarean section was 8.29mg.18 Practically, due to high abdominal pressure and distended intraspinal veins, the drug dose required for spinal anesthesia for puerperae is lower than that of non-puerperae women. However, the dose in the above study was still significantly higher than the ED50 and ED95 of 7.036 mg and 8.709 mg in this study. We believe that the main reason for the difference is that, in this study, after ropivacaine was injected into the subarachnoid space, the lateral decubitus position was maintained for 15 minutes, which enabled the realization of Unilateral spinal anesthesia. Secondly, the puncture point of L2-3 can also reduce the dosage of anesthetic drugs. Advanced age may be another reason.
There are many factors influencing the effect of spinal anesthesia. Age, height, weight, body position, drug specific gravity, liquid volume, concentration, injection speed, puncture point, patient position, abdominal circumference, and even lumbosacral cerebrospinal fluid volume can all affect the anesthesia block plane.19–24 In this trial, we controlled the controllable factors as much as possible, and the patient’s body position, puncture point, drug specific gravity, concentration, and injection speed were all kept consistent. On this basis, statistical analysis first found that age was a statistically significant influencing factor. Moreover, height, as part of the modified sequential protocol, also indisputably influenced the trial results. Furthermore, considering that elderly patients have large differences in body weight, and gender may affect patients’ perception of pain. Finally, four factors of age, gender, height, and weight are included in the statistical model. Then, we used these four factors to build a nomogram in order to more intuitively discover the impact of the inclusion factors on the probability of satisfactory anesthesia.
The dose of spinal anesthesia drugs significantly affect the anesthesia effect, including the analgesia plane, hemodynamics, and even long-term prognosis.25 The physiological homeostasis of the elderly is significantly more likely to be affected due to their weak vascular elasticity and poor nutritional status. At present, there is no unified plan for dose selection for elderly hip fracture surgery. Our study provides a formula for the dose selection of ropivacaine for spinal anesthesia, and the effective rate is 90%, which has high practical value. It is worth mentioning that the definition of satisfactory anesthesia in this study is that there is no pain within the first hour of the operation. Although the duration is not long, it can fully ensure that the dose is not excessive and the hemodynamics is stable. Furthermore, considering that surgically destructive stimulation, including skin incision and reamed intramedullary, occurs mainly within the first hour, the dose provided by the formula can be considered the lowest and optimal option.
Previous literature has suggested that appropriate spinal anesthesia has better perioperative hemodynamic stability than general anesthesia, and the need for intraoperative vasopressors is also significantly reduced.26 In elderly patients, the incidence of blood pressure drop after spinal anesthesia can be as high as 75%.27 In contrast, in this study, the incidence of hypotension after spinal anesthesia was only 20% in stage I and 10% in stage II. The main reason for this advantage is that unilateral anesthesia was well implemented in this trial, and only unilateral sympathetic nerves were blocked as much as possible. Moreover, the definition of satisfactory anesthesia in this study is relatively loose, and it is not mandatory that a single dose can meet the needs of the entire operation, resulting in a significant reduction in drug dosage. In addition to hemodynamics, the postoperative destination is also worthy of attention. In this study, the proportion of patients directly transferred to the general ward after surgery was as high as 86.84% and 93.33% respectively in the two trial stages, which may bring significant improvement in patient satisfaction and also help alleviate the shortage of anesthesia medical resources in China. It is worth noting that in stage II, when dose selection was guided by the calculation formula, the number of patients admitted to the ICU was 0, while the literature reported that the ICU transfer rate was about 7% in the elderly after surgery for hip fracture under general anesthesia.28 Given that the median age of patients in this study was as high as 80 years, the prognostic advantage of reducing the rate of ICU admission may have been greater than expected.
In addition to the above, there are some peculiarities in this study in terms of the trial protocol. First, the puncture site for spinal anesthesia was L2-3, considering that previous studies have provided some dosage options for L3-4.25,29 And due to factors such as hyperosteogenesis and ligament calcification in elderly patients,30 there are always some cases of failed puncture in the L3-4 space. At that time, L2-3 is a safe additional choice. Moreover, ultrasound-guided positioning can ensure the accuracy of puncture point. Second, we chose hyperbaric liquid in this trial, based on the fact that hyperbaric liquid can achieve anesthesia block effect more quickly than hypobaric and isobaric,31,32 and is more popular among surgeons.
There are also some limitations worth discussing in this study. First, this study did not set up a control group, but only a dose-finding test of ropivacaine in a single group. It is still necessary to compare with other commonly used drugs for spinal anesthesia such as bupivacaine in the future to determine the best choice of drug types. Second, this study paid relatively little attention to the prognosis of patients, mainly because we focused on the evaluation of intraoperative anesthesia effect, and the comparison of prognosis also needed to set up a control group. Last but not least, the calculation of the sample size of this study is based on the minimum sample size of logistic regression, which does not mean that the sample size is sufficient. In particular, the efficacy and safety of the calculation formula need to be confirmed by clinical trials with larger samples, or even randomized controlled trials.
At present, the debate on the pros and cons of different anesthesia options for elderly hip fractures is still ongoing. This study starts with spinal anesthesia, focuses on the dose selection of ropivacaine, and gives a specific calculation formula, which meets the requirements of precise anesthesia. Subsequent research can further compare the different densities of drugs and different types of drugs in spinal anesthesia, and screen the optimal general anesthesia scheme at the same time. Finally, comparing the optimal spinal anesthesia scheme with the optimal general anesthesia scheme is the future direction to explore the choice of anesthesia for elderly hip fracture surgery.
Conclusion
In conclusion, this study explored the optimal dose of ropivacaine for spinal anesthesia in elderly hip surgery. The ED50 and ED95 were 7.036 mg and 8.709 mg respectively. A nomogram for predicting satisfactory anesthesia was established with high accuracy. In addition, this study also provides a dose prediction equation of ropivacaine, which has high efficacy and safety, and can guide anesthesiologists in the choice of dose in clinical practice.
Data Sharing Statement
Six months after the main results are published, the individual participant data of this research report can be accessed with the permission of the corresponding authors. The study protocol, statistical analysis plan, and clinical study report will also be available.
Acknowledgments
Appreciate for the support from the Orthopedist and nursing teams of the First Affiliated Hospital of USTC.
Author contributions
All authors made a significant contribution to the work reported, whether that is in the conception, study design, execution, acquisition of data, analysis and interpretation, or in all these areas; took part in drafting, revising or critically reviewing the article; gave final approval of the version to be published; have agreed on the journal to which the article has been submitted; and agree to be accountable for all aspects of the work.
Funding
This research was not funded by any source in the public, commercial, or nonprofit sectors.
Disclosure
The authors report no conflicts of interest in this work.
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LISBON, Portugal ― Screening for Staphylococcus aureus, decolonization, and use of teicoplanin for surgical antimicrobial prophylaxis among patients with methicillin-resistant S aureus (MRSA) lowered the number of prosthetic joint infections in elderly patients undergoing surgery for fracture of the femur.
The findings were presented here as a poster at the 32nd European Congress of Clinical Microbiology & Infectious Diseases (ECCMID) 2022, which was one of the few awarded the accolade of “top-rated poster.”
“We actually found that with our intervention, all prosthetic joint infections decreased, not just the Staphylococcus aureus but those due to MRSA, too,” said Natividad Benito, MD, an infectious diseases specialist at Hospital de la Santa Creu i Sant Pau in Barcelona, Spain, in an interview with Medscape Medical News. “We’re pleased with these results because prosthetic joint infections present such a complicated situation for patients and surgeons. This is also a relatively easy intervention to use, and with time, even the PCR [polymerase chain reaction] technology will become cheaper. Now, in our hospital, prosthetic joint infections are rare.”
At the Hospital de la Santa Creu i Sant Pau, around 200 hip hemiarthroplasties are performed per year. Preceding the intervention, the hospital recorded 11 prosthetic joint infections, with up to five infections due to S aureus and up to four due to MRSA.
The intervention was introduced in 2016. After 2 years, there were no cases of prosthetic joint infections due to S aureus; in 2018 there, was one case of prosthetic joint infection due to MRSA. In 2019, there was one case of prosthetic joint infection, but it was due neither to S aureus nor MRSA. In 2020 and 2021, there was one infection each year that was due to MRSA.
Jesús Rodríguez Baño, MD,head of the Infectious Diseases Division, Hospital Universitario Virgen Macarena at the University of Seville, Spain, who was not involved in the study, explained that for patients with hip fracture, “the time frame in which colonization can be studied is too short using traditional methods. Prosthetic joint infections in this population have a devastating effect, with not negligible mortality and very important morbidity and healthcare costs.”
Referring to the significant reduction in the rate of S aureus prosthetic joint infections in the postintervention period, Rodríguez Baño told Medscape Medical News, “The results are sound, and the important reduction in infection risk invites for the development of a multicenter, randomized trial to confirm these interesting results.
“The authors are commended for measuring the impact of applying a well-justified preventive protocol,” RodríguezBaño added. However, the study has some limitations: “It was performed in one center, it was not randomized, and control for potential confounders is needed.”
Decolonization in an Emergency Femur Fracture
This study addressed a particular need in residents of Spain’s long-term care facilities. In 2016, the prevalence of MRSA was high.
Roughly one third of the general population carry S aureus in their nose. In care homes, the rate of MRSA is higher than in the general population, at around 30% of those with S aureus. In Spain, recommendations for patients undergoing elective total joint arthroplasty advise S aureus decolonization — which can take 5 days — to prevent surgical site infections.
“The problem with the elderly population is not only have they a higher incidence of MRSA but that the surgical prophylaxis is inadequate for MRSA,” Benito pointed out.
Many patients in long-term care facilities are elderly and frail and are at greater risk of fracture. Unlike elective hip surgery, in which patients are asked to undergo decolonization over the 5 days prior to their operation, with emergent femur fractures, there is insufficient time for such preparation. “These patients with femur fractures need surgery as soon as possible,” said Benito.
No studies have been conducted to determine the best way to minimize infection risk from S aureus and MRSA for patients undergoing emergency hip hemiarthroplasty surgery to treat femoral fractures.
In the current study, Benito and her co-authors assessed whether a bundle of measures — including rapid detection of S aureus nasal carriage by PCR upon arrival in the emergency setting, followed by decolonization of carriers using a topical treatment in the nose and a prescription of surgical antimicrobial prophylaxis (adapted antibiotic prophylaxis for MRSA) — reduces the incidence of prosthetic joint infections after surgery.
The quasi-experimental single-center study included patients admitted to the emergency department at Hospital de la Santa Creu i Sant Pau. The PCR was rapid, with a turnaround of just 1.5 hours. Decolonization of S aureus carriers was carried out using nasal mupirocin and chlorhexidine gluconate bathing, which was started immediately. It was used for a total of 5 days and was usually continued throughout and after surgery.
Patients carrying MRSA received teicoplanin as optimal surgical antimicrobial prophylaxis instead of cefazolin. The intervention did not interfere with the timing of surgery. The study’s principal outcomes were overall incidence of prosthetic joint infections and the incidence of those specifically caused by S aureus and MRSA.
The researchers compared findings regarding these outcomes over 5 consecutive years of the intervention to outcomes during 4 consecutive years prior to the intervention, which started in 2016.
In 2016–2020, from 22% to 31% of the overall number of patients requiring hip hemiarthroplasty were referred from long-term care facilities. From 25% to 29% of these patients tested positive for S aureus on PCR, and of these, 33% to 64% had MRSA.
There were 772 surgical procedures from 2012–2015 and 786 from 2017–2020.
Prior to the intervention, over the years 2012–2014, S aureus caused 36% to 50% of prosthetic joint infections; 25% to 100% of the S aureus infections were MRSA. This decreased significantly after the intervention.
In 2016–2020, there was an average of 14 prosthetic joint infections (1.5%), compared to 36 (4.7%) in 2012–2015 (P < .001). Similarly, the incidence of prosthetic joint infections due to S aureus dropped to 0.3% from 1.8% (P < .002). The incidence of MRSA prosthetic joint infections was 0.3% for 2016–2020, vs 1.2% for 2012–2015 (P = .012).
The years 2018, 2020, and 2021 each saw one case of infection due to MRSA. They were most likely due to “the intervention not being performed properly in all cases,” said Benito.
A prosthetic joint infection is very serious for the patient. “It means reoperating, because antibiotics are not enough to clear the infection. The biofilm and pus of the infection need to be cleaned out, a new prosthesis is needed, after which more antibiotics are needed for around 2 months, which can be hard to tolerate, and even then, the infection might not be eradicated,” explained Benito. “Many of these people are old and frail, and mortality can be significant. Getting a prosthetic joint infection is catastrophic for these patients.”
32nd European Congress of Clinical Microbiology & Infectious Diseases (ECCMID) 2022: Abstract 02516.
Benitos and Rodríguez-Baño have disclosed no relevant financial relationships.
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A randomized controlled trial (RCT) comparing spinal versus general anesthesia for hip surgery found that spinal anesthesia was associated with worse pain immediately after surgery and higher rates of pain reliever prescriptions at 60 days. However, differences in pain, satisfaction, or mental status between the two interventions seemed to diminish at 60, 180, or 365 days after surgery. The findings are published in Annals of Internal Medicine.
More than 250,000 older adults experience a hip fracture every year and nearly all are repaired through surgery. Patient recovery of ambulation and survival at 60 days, delirium, and hospital length of stay are similar whether patients have spinal or general anesthesia during surgery. Not much is known about which type of anesthesia demonstrates better outcomes, though previous studies suggest that patients may have less pain in the first few hours after hip fracture surgery with spinal anesthesia.
Researchers from the University of Pennsylvania Perelman School of Medicine conducted a preplanned secondary analysis of a RCT comparing spinal versus general anesthesia in 1,600 patients aged 50 years or older who were having hip fracture surgery. Trial participants were randomly assigned to general or spinal anesthesia and the researchers collected data on pain on days 1 to 3 after surgery. Pain and use of prescription pain relievers, mental status, and patient satisfaction were assessed at 60, 180, and 365 days after surgery. They authors found that patients who received spinal anesthesia reported worse pain in the 24 hours after surgery but reported similar pain at all other time points. The authors also found that 25 percent of patients in the spinal anesthesia group were using prescription pain relievers at 60 days compared to 18.8 percent of patients in the general anesthesia group. However, the authors note that they did not find differences in pain, satisfaction, or mental status at 60, 180, or 365 days.
In an accompanying editorial, authors from Harvard Medical School argue that this study challenges a dominant narrative about the risks and outcomes of general anesthesia in older adults. The authors also add that this study highlights that surgical repair of hip fractures in older adults carries the risk for severe postoperative pain, regardless of whether the surgery is done with regional or general anesthesia. They suggest that future research investigate the differences in reported pain as presented in this study and the RAGA (Regional Anesthesia vs General Anesthesia) trial but note that participants in the RAGA trial may have experienced more extensive postoperative care.