Orthopedics

NEW ORLEANS—Genetics, cartilage type, and other factors may help senior athletes maintain well-functioning hips and stave off osteoarthritis even when radiographic results indicate abnormalities, according to research presented at the 2014 Annual Meeting of the American Academy of Orthopaedic Surgeons (AAOS).

It is not known whether morphological abnormalities of the hip are compatible with life-long hip function and avoidance of osteoarthritis. Lucas Anderson, MD, from the University of Utah in Salt Lake City, and colleagues sought to investigate the prevalence of radiographic findings consistent with dysplasia and femoroacetabular impingement in senior athletes with well-functioning hips.

A total of 546 senior athletes (55% men, 45% women), average age 67 years (range 50 to 91) participated in this study. Two orthopedic surgeons independently evaluated 1,087 hips (excluding hip fractures) for radiographic signs of dysplasia and femoroacetabular impingement. Alpha angle was measured on frog-lateral and anteroposterior radiographs. Lateral center edge angle, acetabular index, and crossover sign were measured on anteroposterior films. Radiographic interpretations were averaged between 2 observers to assess prevalence of dysplasia, femoroacetabular impingement, and osteoarthritis. Cam femoroacetabular impingement was noted if the alpha angle was 50° or greater on either radiograph. Pincer femoroacetabular impingement was noted if lateral center edge angle was greater than 39°, acetabular index was less than 0°, and/or a positive crossover sign was detected. Dysplasia was noted if center edge angle was less than 20° and/or acetabular index was greater than 10°. A chi-squared analysis was used to assess for associations between osteoarthritis (Tönnis grade 2-3) and dysplasia and femoroacetabular impingement. Dysplasia and femoroacetabular impingement were then analyzed using a mixed-effect logistic regression model.

Nine percent of hips (99) had radiographic evidence for dysplasia; 3% (28) had a lateral center edge angle that was less than 20° and 8% (89) had an acetabular index that was greater than 10°. Just over 80% of hips had radiographic evidence of femoroacetabular impingement; 67% had isolated cam, 8% isolated pincer impingement, and 24% of hips had mixed femoroacetabular impingement. Osteoarthritis was present in 17% of hips; 93% of hips with osteoarthritis also had radiographic femoroacetabular impingement and 10% dysplasia. Hips with osteoarthritis were more likely to have radiographic evidence of femoroacetabular impingement (odds ratio = 3.7). However, 80% of the hips with findings of femoroacetabular impingement had no evidence of osteoarthritis despite the athletes’ age and lifelong activity levels. Femoroacetabular impingement was more prevalent in males than females (odds ratio = 10.7).

While the data suggest that senior athletes with femoroacetabular impingement are at a greater risk for having radiographic evidence of osteoarthritis, a substantial portion of the senior athletes in this study did not have osteoarthritis. While femoroacetabular impingement and dysplasia have historically been associated with development of early osteoarthritis, this study suggests that there may be other factors, such as genetics and cartilage type, which may play a joint-preserving role despite presence of pathomorphology in this series of high-functioning senior athletes.

NEW ORLEANS—Genetics, cartilage type, and other factors may help senior athletes maintain well-functioning hips and stave off osteoarthritis even when radiographic results indicate abnormalities, according to research presented at the 2014 Annual Meeting of the American Academy of Orthopaedic Surgeons (AAOS).

It is not known whether morphological abnormalities of the hip are compatible with life-long hip function and avoidance of osteoarthritis. Lucas Anderson, MD, from the University of Utah in Salt Lake City, and colleagues sought to investigate the prevalence of radiographic findings consistent with dysplasia and femoroacetabular impingement in senior athletes with well-functioning hips.

A total of 546 senior athletes (55% men, 45% women), average age 67 years (range 50 to 91) participated in this study. Two orthopedic surgeons independently evaluated 1,087 hips (excluding hip fractures) for radiographic signs of dysplasia and femoroacetabular impingement. Alpha angle was measured on frog-lateral and anteroposterior radiographs. Lateral center edge angle, acetabular index, and crossover sign were measured on anteroposterior films. Radiographic interpretations were averaged between 2 observers to assess prevalence of dysplasia, femoroacetabular impingement, and osteoarthritis. Cam femoroacetabular impingement was noted if the alpha angle was 50° or greater on either radiograph. Pincer femoroacetabular impingement was noted if lateral center edge angle was greater than 39°, acetabular index was less than 0°, and/or a positive crossover sign was detected. Dysplasia was noted if center edge angle was less than 20° and/or acetabular index was greater than 10°. A chi-squared analysis was used to assess for associations between osteoarthritis (Tönnis grade 2-3) and dysplasia and femoroacetabular impingement. Dysplasia and femoroacetabular impingement were then analyzed using a mixed-effect logistic regression model.

Nine percent of hips (99) had radiographic evidence for dysplasia; 3% (28) had a lateral center edge angle that was less than 20° and 8% (89) had an acetabular index that was greater than 10°. Just over 80% of hips had radiographic evidence of femoroacetabular impingement; 67% had isolated cam, 8% isolated pincer impingement, and 24% of hips had mixed femoroacetabular impingement. Osteoarthritis was present in 17% of hips; 93% of hips with osteoarthritis also had radiographic femoroacetabular impingement and 10% dysplasia. Hips with osteoarthritis were more likely to have radiographic evidence of femoroacetabular impingement (odds ratio = 3.7). However, 80% of the hips with findings of femoroacetabular impingement had no evidence of osteoarthritis despite the athletes’ age and lifelong activity levels. Femoroacetabular impingement was more prevalent in males than females (odds ratio = 10.7).

While the data suggest that senior athletes with femoroacetabular impingement are at a greater risk for having radiographic evidence of osteoarthritis, a substantial portion of the senior athletes in this study did not have osteoarthritis. While femoroacetabular impingement and dysplasia have historically been associated with development of early osteoarthritis, this study suggests that there may be other factors, such as genetics and cartilage type, which may play a joint-preserving role despite presence of pathomorphology in this series of high-functioning senior athletes.

NEW ORLEANS—Genetics, cartilage type, and other factors may help senior athletes maintain well-functioning hips and stave off osteoarthritis even when radiographic results indicate abnormalities, according to research presented at the 2014 Annual Meeting of the American Academy of Orthopaedic Surgeons (AAOS).

It is not known whether morphological abnormalities of the hip are compatible with life-long hip function and avoidance of osteoarthritis. Lucas Anderson, MD, from the University of Utah in Salt Lake City, and colleagues sought to investigate the prevalence of radiographic findings consistent with dysplasia and femoroacetabular impingement in senior athletes with well-functioning hips.

A total of 546 senior athletes (55% men, 45% women), average age 67 years (range 50 to 91) participated in this study. Two orthopedic surgeons independently evaluated 1,087 hips (excluding hip fractures) for radiographic signs of dysplasia and femoroacetabular impingement. Alpha angle was measured on frog-lateral and anteroposterior radiographs. Lateral center edge angle, acetabular index, and crossover sign were measured on anteroposterior films. Radiographic interpretations were averaged between 2 observers to assess prevalence of dysplasia, femoroacetabular impingement, and osteoarthritis. Cam femoroacetabular impingement was noted if the alpha angle was 50° or greater on either radiograph. Pincer femoroacetabular impingement was noted if lateral center edge angle was greater than 39°, acetabular index was less than 0°, and/or a positive crossover sign was detected. Dysplasia was noted if center edge angle was less than 20° and/or acetabular index was greater than 10°. A chi-squared analysis was used to assess for associations between osteoarthritis (Tönnis grade 2-3) and dysplasia and femoroacetabular impingement. Dysplasia and femoroacetabular impingement were then analyzed using a mixed-effect logistic regression model.

Nine percent of hips (99) had radiographic evidence for dysplasia; 3% (28) had a lateral center edge angle that was less than 20° and 8% (89) had an acetabular index that was greater than 10°. Just over 80% of hips had radiographic evidence of femoroacetabular impingement; 67% had isolated cam, 8% isolated pincer impingement, and 24% of hips had mixed femoroacetabular impingement. Osteoarthritis was present in 17% of hips; 93% of hips with osteoarthritis also had radiographic femoroacetabular impingement and 10% dysplasia. Hips with osteoarthritis were more likely to have radiographic evidence of femoroacetabular impingement (odds ratio = 3.7). However, 80% of the hips with findings of femoroacetabular impingement had no evidence of osteoarthritis despite the athletes’ age and lifelong activity levels. Femoroacetabular impingement was more prevalent in males than females (odds ratio = 10.7).

While the data suggest that senior athletes with femoroacetabular impingement are at a greater risk for having radiographic evidence of osteoarthritis, a substantial portion of the senior athletes in this study did not have osteoarthritis. While femoroacetabular impingement and dysplasia have historically been associated with development of early osteoarthritis, this study suggests that there may be other factors, such as genetics and cartilage type, which may play a joint-preserving role despite presence of pathomorphology in this series of high-functioning senior athletes.

NEW ORLEANS—Participation in extreme sports offers excitement not found in traditional team sports and also comes with significant risk, according to researchers reporting at the 2014 Annual Meeting of the American Academy of Orthopaedic Surgeons (AAOS).

Since their conception during the mid-1970s, international participation in extreme sports has steadily grown. While many traditional sports have declined in participation, skateboarding has surged 49% to 14 million US participants and snowboarding now claims 7.2 million participants, up 51% from 1999. The recent death of extreme snowmobiler Caleb Moore at the 2013 Winter X games has demonstrated the serious risks associated with these sports.

In a presentation titled “Incidence of Head and Neck Injuries in Extreme Sports,” Vinay K. Sharma, MD, summarized the findings of a first-of-its-kind study. Dr. Sharma and colleagues reviewed 2000–2011 National Electronic Injury Surveillance System (NEISS) data for seven popular sports featured in the Winter and Summer X Games: surfing, mountain biking, motocross, skateboarding, snowboarding, snowmobiling, and snow skiing. Data from the NEISS database was collected for each individual sport per year and type of head and neck injury. Cumulative data for overall incidence and injuries over entire 11-year period was then calculated. National estimates were based off NEISS weighted calculations using US census data.

Of the over 4 million injuries reported for extreme sports participants between 2000–2011, 11.3% were head and neck injuries. Of all head and neck injuries reported in extreme sports, 83% were head injuries and 17% neck injuries. The 4 sports with the highest total incidence of reported head and neck injuries were skateboarding (129,600), snowboarding (97,527), skiing (83,313), and motocross (78,236). Severe head and neck injuries (cervical or skull fracture) had a reported total incidence of 2.5% of extreme sports head and neck injuries. Although the incidence of extreme sports HNI increased from year 2000 (34,065) to 2010 (40,042), this trend is not consistent from year to year.

According to Dr. Sharma and colleagues, a greater awareness of the dangers associated with extreme sports offers an opportunity for sports medicine and orthopedic physicians to advocate for safer equipment, improved on-site medical care, and further research regarding extreme sports injuries.

NEW ORLEANS—Participation in extreme sports offers excitement not found in traditional team sports and also comes with significant risk, according to researchers reporting at the 2014 Annual Meeting of the American Academy of Orthopaedic Surgeons (AAOS).

Since their conception during the mid-1970s, international participation in extreme sports has steadily grown. While many traditional sports have declined in participation, skateboarding has surged 49% to 14 million US participants and snowboarding now claims 7.2 million participants, up 51% from 1999. The recent death of extreme snowmobiler Caleb Moore at the 2013 Winter X games has demonstrated the serious risks associated with these sports.

In a presentation titled “Incidence of Head and Neck Injuries in Extreme Sports,” Vinay K. Sharma, MD, summarized the findings of a first-of-its-kind study. Dr. Sharma and colleagues reviewed 2000–2011 National Electronic Injury Surveillance System (NEISS) data for seven popular sports featured in the Winter and Summer X Games: surfing, mountain biking, motocross, skateboarding, snowboarding, snowmobiling, and snow skiing. Data from the NEISS database was collected for each individual sport per year and type of head and neck injury. Cumulative data for overall incidence and injuries over entire 11-year period was then calculated. National estimates were based off NEISS weighted calculations using US census data.

Of the over 4 million injuries reported for extreme sports participants between 2000–2011, 11.3% were head and neck injuries. Of all head and neck injuries reported in extreme sports, 83% were head injuries and 17% neck injuries. The 4 sports with the highest total incidence of reported head and neck injuries were skateboarding (129,600), snowboarding (97,527), skiing (83,313), and motocross (78,236). Severe head and neck injuries (cervical or skull fracture) had a reported total incidence of 2.5% of extreme sports head and neck injuries. Although the incidence of extreme sports HNI increased from year 2000 (34,065) to 2010 (40,042), this trend is not consistent from year to year.

According to Dr. Sharma and colleagues, a greater awareness of the dangers associated with extreme sports offers an opportunity for sports medicine and orthopedic physicians to advocate for safer equipment, improved on-site medical care, and further research regarding extreme sports injuries.

NEW ORLEANS—Participation in extreme sports offers excitement not found in traditional team sports and also comes with significant risk, according to researchers reporting at the 2014 Annual Meeting of the American Academy of Orthopaedic Surgeons (AAOS).

Since their conception during the mid-1970s, international participation in extreme sports has steadily grown. While many traditional sports have declined in participation, skateboarding has surged 49% to 14 million US participants and snowboarding now claims 7.2 million participants, up 51% from 1999. The recent death of extreme snowmobiler Caleb Moore at the 2013 Winter X games has demonstrated the serious risks associated with these sports.

In a presentation titled “Incidence of Head and Neck Injuries in Extreme Sports,” Vinay K. Sharma, MD, summarized the findings of a first-of-its-kind study. Dr. Sharma and colleagues reviewed 2000–2011 National Electronic Injury Surveillance System (NEISS) data for seven popular sports featured in the Winter and Summer X Games: surfing, mountain biking, motocross, skateboarding, snowboarding, snowmobiling, and snow skiing. Data from the NEISS database was collected for each individual sport per year and type of head and neck injury. Cumulative data for overall incidence and injuries over entire 11-year period was then calculated. National estimates were based off NEISS weighted calculations using US census data.

Of the over 4 million injuries reported for extreme sports participants between 2000–2011, 11.3% were head and neck injuries. Of all head and neck injuries reported in extreme sports, 83% were head injuries and 17% neck injuries. The 4 sports with the highest total incidence of reported head and neck injuries were skateboarding (129,600), snowboarding (97,527), skiing (83,313), and motocross (78,236). Severe head and neck injuries (cervical or skull fracture) had a reported total incidence of 2.5% of extreme sports head and neck injuries. Although the incidence of extreme sports HNI increased from year 2000 (34,065) to 2010 (40,042), this trend is not consistent from year to year.

According to Dr. Sharma and colleagues, a greater awareness of the dangers associated with extreme sports offers an opportunity for sports medicine and orthopedic physicians to advocate for safer equipment, improved on-site medical care, and further research regarding extreme sports injuries.

NEW ORLEANS—Middle-aged women with rheumatoid arthritis or arthritis resulting from an injury are among the patients most likely to experience serious pain following a knee replacement, according to researchers from Hospital for Special Surgery, who reported their findings at the 2014 Annual Meeting of the American Academy of Orthopaedic Surgeons (AAOS).

One of the biggest concerns patients have is the amount of pain they will have after knee replacement surgery. Although it is a very successful operation overall to relieve arthritis pain and restore function, persistent postoperative pain can be a problem for some patients. Researchers at Hospital for Special Surgery in New York set out to determine which groups of patients were at highest risk for increased postoperative pain based on demographic and surgical variables.

“There is no question that pain after total knee replacement is greater than that after total knee replacement,” said senior study author Thomas P. Sculco, MD, the hospital’s Surgeon-in-Chief. “Many factors play a role, and our studies found that younger female patients, particularly those with posttraumatic or rheumatoid arthritis, have the highest pain scores.”

In two companion studies also presented at the AAOS Annual Meeting, Dr. Sculco and colleagues found that surgical factors like having general anesthesia or a longer tourniquet time during knee replacement can also contribute to pain following surgery.

For the studies, the researchers reviewed hospital records for 273 patients who underwent total knee replacement from October 2007 to March 2010. For the first study, investigators looked at demographic data such as gender, ethnicity, age, height, weight, type of knee arthritis, and co-existing medical conditions. They also looked at the knee’s preoperative range of motion, how well the patients could walk, and the amount of pain they had before surgery.

The strongest predictors for severe postoperative pain during rest included being female; being between the ages of 45 and 65; having posttraumatic arthritis spurred by an injury, rheumatoid arthritis, or osteoarthritis; being obese; and having a higher level of pain at the time of hospital admission. Patients with avascular necrosis had significantly lower postoperative pain.

Obesity, a higher pain level during hospital admission, and being between the ages of 45 and 65 were the strongest predictors of postoperative pain during periods of activity. Patients who were Asian or Caucasian, and those with either underlying osteoarthritis or avascular necrosis, or both, had lower postoperative pain during periods of activity.

“Before patients come in to the hospital, surgeons should have a thorough discussion with them regarding postoperative pain, particularly in the groups that we found tended to have more pain,” Dr. Sculco said. “More aggressive pain management techniques may be necessary for these patients.”

For the second study, the researchers used the same medical records to gather information about surgical variables including the length of the incision, type of arthrotomy, tourniquet time and pressure, how long the procedure took, estimated blood loss, and radiographic assessment including the amount of knee deformity and implant positioning and alignment.

Risk factors for severe postoperative pain at rest included having general anesthesia, longer tourniquet time, more blood loss, and having a large kneecap. Predictors of pain during activity included having a large kneecap and techniques such as overstuffing of the patellofemoral joint.

Surgical technique can play a role in reducing pain, Dr. Sculco said. “The surgeon must be aware not to use an implant that is too large for the knee, or a kneecap component that is excessive in size. In addition, the location of the joint line must be accurately positioned after the knee replacement. If it is too high it may lead to increased pain.” Patients with epidural anesthesia also tended to have less pain than those who had general anesthesia.

“Technical accuracy is important, particularly the alignment, patella sizing, and joint line level,” Dr. Sculco said. “Patients with more complex preoperative deformities often require increased operative time and surgical dissection, which in turn leads to increased pain, especially in the younger female patients.”

NEW ORLEANS—Middle-aged women with rheumatoid arthritis or arthritis resulting from an injury are among the patients most likely to experience serious pain following a knee replacement, according to researchers from Hospital for Special Surgery, who reported their findings at the 2014 Annual Meeting of the American Academy of Orthopaedic Surgeons (AAOS).

One of the biggest concerns patients have is the amount of pain they will have after knee replacement surgery. Although it is a very successful operation overall to relieve arthritis pain and restore function, persistent postoperative pain can be a problem for some patients. Researchers at Hospital for Special Surgery in New York set out to determine which groups of patients were at highest risk for increased postoperative pain based on demographic and surgical variables.

“There is no question that pain after total knee replacement is greater than that after total knee replacement,” said senior study author Thomas P. Sculco, MD, the hospital’s Surgeon-in-Chief. “Many factors play a role, and our studies found that younger female patients, particularly those with posttraumatic or rheumatoid arthritis, have the highest pain scores.”

In two companion studies also presented at the AAOS Annual Meeting, Dr. Sculco and colleagues found that surgical factors like having general anesthesia or a longer tourniquet time during knee replacement can also contribute to pain following surgery.

For the studies, the researchers reviewed hospital records for 273 patients who underwent total knee replacement from October 2007 to March 2010. For the first study, investigators looked at demographic data such as gender, ethnicity, age, height, weight, type of knee arthritis, and co-existing medical conditions. They also looked at the knee’s preoperative range of motion, how well the patients could walk, and the amount of pain they had before surgery.

The strongest predictors for severe postoperative pain during rest included being female; being between the ages of 45 and 65; having posttraumatic arthritis spurred by an injury, rheumatoid arthritis, or osteoarthritis; being obese; and having a higher level of pain at the time of hospital admission. Patients with avascular necrosis had significantly lower postoperative pain.

Obesity, a higher pain level during hospital admission, and being between the ages of 45 and 65 were the strongest predictors of postoperative pain during periods of activity. Patients who were Asian or Caucasian, and those with either underlying osteoarthritis or avascular necrosis, or both, had lower postoperative pain during periods of activity.

“Before patients come in to the hospital, surgeons should have a thorough discussion with them regarding postoperative pain, particularly in the groups that we found tended to have more pain,” Dr. Sculco said. “More aggressive pain management techniques may be necessary for these patients.”

For the second study, the researchers used the same medical records to gather information about surgical variables including the length of the incision, type of arthrotomy, tourniquet time and pressure, how long the procedure took, estimated blood loss, and radiographic assessment including the amount of knee deformity and implant positioning and alignment.

Risk factors for severe postoperative pain at rest included having general anesthesia, longer tourniquet time, more blood loss, and having a large kneecap. Predictors of pain during activity included having a large kneecap and techniques such as overstuffing of the patellofemoral joint.

Surgical technique can play a role in reducing pain, Dr. Sculco said. “The surgeon must be aware not to use an implant that is too large for the knee, or a kneecap component that is excessive in size. In addition, the location of the joint line must be accurately positioned after the knee replacement. If it is too high it may lead to increased pain.” Patients with epidural anesthesia also tended to have less pain than those who had general anesthesia.

“Technical accuracy is important, particularly the alignment, patella sizing, and joint line level,” Dr. Sculco said. “Patients with more complex preoperative deformities often require increased operative time and surgical dissection, which in turn leads to increased pain, especially in the younger female patients.”

NEW ORLEANS—Middle-aged women with rheumatoid arthritis or arthritis resulting from an injury are among the patients most likely to experience serious pain following a knee replacement, according to researchers from Hospital for Special Surgery, who reported their findings at the 2014 Annual Meeting of the American Academy of Orthopaedic Surgeons (AAOS).

One of the biggest concerns patients have is the amount of pain they will have after knee replacement surgery. Although it is a very successful operation overall to relieve arthritis pain and restore function, persistent postoperative pain can be a problem for some patients. Researchers at Hospital for Special Surgery in New York set out to determine which groups of patients were at highest risk for increased postoperative pain based on demographic and surgical variables.

“There is no question that pain after total knee replacement is greater than that after total knee replacement,” said senior study author Thomas P. Sculco, MD, the hospital’s Surgeon-in-Chief. “Many factors play a role, and our studies found that younger female patients, particularly those with posttraumatic or rheumatoid arthritis, have the highest pain scores.”

In two companion studies also presented at the AAOS Annual Meeting, Dr. Sculco and colleagues found that surgical factors like having general anesthesia or a longer tourniquet time during knee replacement can also contribute to pain following surgery.

For the studies, the researchers reviewed hospital records for 273 patients who underwent total knee replacement from October 2007 to March 2010. For the first study, investigators looked at demographic data such as gender, ethnicity, age, height, weight, type of knee arthritis, and co-existing medical conditions. They also looked at the knee’s preoperative range of motion, how well the patients could walk, and the amount of pain they had before surgery.

The strongest predictors for severe postoperative pain during rest included being female; being between the ages of 45 and 65; having posttraumatic arthritis spurred by an injury, rheumatoid arthritis, or osteoarthritis; being obese; and having a higher level of pain at the time of hospital admission. Patients with avascular necrosis had significantly lower postoperative pain.

Obesity, a higher pain level during hospital admission, and being between the ages of 45 and 65 were the strongest predictors of postoperative pain during periods of activity. Patients who were Asian or Caucasian, and those with either underlying osteoarthritis or avascular necrosis, or both, had lower postoperative pain during periods of activity.

“Before patients come in to the hospital, surgeons should have a thorough discussion with them regarding postoperative pain, particularly in the groups that we found tended to have more pain,” Dr. Sculco said. “More aggressive pain management techniques may be necessary for these patients.”

For the second study, the researchers used the same medical records to gather information about surgical variables including the length of the incision, type of arthrotomy, tourniquet time and pressure, how long the procedure took, estimated blood loss, and radiographic assessment including the amount of knee deformity and implant positioning and alignment.

Risk factors for severe postoperative pain at rest included having general anesthesia, longer tourniquet time, more blood loss, and having a large kneecap. Predictors of pain during activity included having a large kneecap and techniques such as overstuffing of the patellofemoral joint.

Surgical technique can play a role in reducing pain, Dr. Sculco said. “The surgeon must be aware not to use an implant that is too large for the knee, or a kneecap component that is excessive in size. In addition, the location of the joint line must be accurately positioned after the knee replacement. If it is too high it may lead to increased pain.” Patients with epidural anesthesia also tended to have less pain than those who had general anesthesia.

“Technical accuracy is important, particularly the alignment, patella sizing, and joint line level,” Dr. Sculco said. “Patients with more complex preoperative deformities often require increased operative time and surgical dissection, which in turn leads to increased pain, especially in the younger female patients.”

NEW ORLEANS—More than 7 million Americans are living with an artificial knee (4.7 million) or hip (2.5 million), which may have significant future implications in terms of the need for ongoing patient care, according to new research presented at the 2014 Annual Meeting of the American Academy of Orthopaedic Surgeons (AAOS). Two related studies also found a growing incidence of adults younger than age 65 undergoing total knee replacement (TKR) and total hip replacement (THR) surgeries, and a potential underutilization of these procedures in some segments of the population.

While numerous studies have quantified the incidence rate of TKR and THR in the United States, there is very little information about the number of patients actually living with a prosthetic knee or hip. In a presentation titled “Prevalence of Total Hip (THA) and Total Knee (TKA) Arthroplasty in the United States,” researchers reviewed THR and TKR incidence rates, mortality rates, and relative mortality rates (the difference in survival between THR and TKR patients and the general population) over a 40-year period to estimate 2010 prevalence rates according to age, sex, and time since surgery.

Among the study findings:

• Approximately 0.8% of Americans are living with a hip replacement and 1.5% with a knee replacement.

• More women are living with prosthetic hips and knees than men.

• Prevalence of THR and TKR among adults age 50 and older is as high as 2.3% and 4.6%, respectively.

• The prevalence of THR rises to nearly 6% by 80 years of age. The prevalence of TKR rises to nearly 10% by 80 years of age.

• The states with the highest number of THR and TKR patients are California, Florida, and Texas; the two states with the lowest numbers are Alaska and Hawaii.

“This study shows that around 7 million Americans have a hip or knee replacement,” said Daniel Berry, MD, Professor of Orthopaedics at Mayo Clinic and the senior author of the study. “This large number highlights how these operations have kept a substantial part of our population mobile despite severe arthritis, something that wouldn’t have been possible before these technologies were available. These relatively high prevalence estimates also highlight the significant ongoing need to care for all of the patients with total hip and knee replacement. These prevalence estimates are within the same ballpark as coronary heart disease, and much higher than heart failure or stroke. To put these numbers in perspective, there are roughly one and a half times as many people living with a hip or knee replacement in the US as people living with heart failure.”

Individuals with total hip and knee replacement often are complex patients with multiple chronic conditions,” added William A. Jiranek, MD, Professor of Orthopaedics at Virginia Commonwealth University School of Medicine. “They all need continuing medical attention and some need further surgical attention over the years of having a replacement. As “there are no guidelines to define long-term management of these individuals … our prevalence estimates are vital to agencies charged with planning for the provision of health care services.”

In two related studies presented at the annual meeting—“Trends in Total Hip Arthroplasty in the United States: The Shift to a Younger Demographic” and “Trends in Total Knee Arthroplasty in the United States: Understanding the Shift to a Younger Demographic”—researchers conducted a retrospective review of 2000 to 2009 hospital discharge data on TKR and THR patients from the Nationwide Inpatient Sample (NIS) Healthcare Cost and Utilization Project (HCUP). Researchers looked at procedural rates, gender, race, age, payer type, length of stay (LOS), discharge disposition, and revision burden for each year, stratified by age. US National Census data was used to calculate rates for each procedure per 100,000 US populations within each age group.

Among the study findings:

• The incidence of TKR increased by 120% from 2000 to 2009: 188% for patients ages 45 to 64, and 89% for patients ages 65 to 84. The incidence of THR increased 73% from 2000 to 2009: 123% for patients ages 45 to 64, and 54% for ages 65 to 84.

• The number of revision total knee replacement (RTKR) procedures increased 133%, and the number of revision total hip replacement (RTHR) procedures by 27%.

• The increase in TKR and THR patients is primarily due to “the disproportionate growth in the rate of utilization among younger patients, and secondarily by overall population growth.”

• Medicare was the primary payer for 63.3% of all TKRs and 58.2% of THRs in 2000, and 54.7% of TKRs and 52.8% of THRs in 2009.

• The proportion of TKR patients discharged with home health care increased from 19.1% in 2000 to 40.5 % in 2009; and the number of THR patients, from 18.9% in 2000 to 40.8% in 2009.

• Race and gender distribution have remained relatively stable for TKR, RTKR, THR, and RTHR.

“Our data demonstrate that increases in the number of primary and revision knee and hip arthroplasties have been driven predominately by increased procedural rates, as opposed to population demographics,” said lead study author Jacob M. Drew, MD, of the University of Massachusetts Medical School.

In addition, “while shifts in age strata seem to be ongoing, race and gender distribution have remained relatively stable for both TKR and THR,” said Dr. Drew. “This suggests that well-documented racial disparity in total joint replacement (TJR) persists, and that there remains a substantial population in whom TJR is underutilized.”

NEW ORLEANS—More than 7 million Americans are living with an artificial knee (4.7 million) or hip (2.5 million), which may have significant future implications in terms of the need for ongoing patient care, according to new research presented at the 2014 Annual Meeting of the American Academy of Orthopaedic Surgeons (AAOS). Two related studies also found a growing incidence of adults younger than age 65 undergoing total knee replacement (TKR) and total hip replacement (THR) surgeries, and a potential underutilization of these procedures in some segments of the population.

While numerous studies have quantified the incidence rate of TKR and THR in the United States, there is very little information about the number of patients actually living with a prosthetic knee or hip. In a presentation titled “Prevalence of Total Hip (THA) and Total Knee (TKA) Arthroplasty in the United States,” researchers reviewed THR and TKR incidence rates, mortality rates, and relative mortality rates (the difference in survival between THR and TKR patients and the general population) over a 40-year period to estimate 2010 prevalence rates according to age, sex, and time since surgery.

Among the study findings:

• Approximately 0.8% of Americans are living with a hip replacement and 1.5% with a knee replacement.

• More women are living with prosthetic hips and knees than men.

• Prevalence of THR and TKR among adults age 50 and older is as high as 2.3% and 4.6%, respectively.

• The prevalence of THR rises to nearly 6% by 80 years of age. The prevalence of TKR rises to nearly 10% by 80 years of age.

• The states with the highest number of THR and TKR patients are California, Florida, and Texas; the two states with the lowest numbers are Alaska and Hawaii.

“This study shows that around 7 million Americans have a hip or knee replacement,” said Daniel Berry, MD, Professor of Orthopaedics at Mayo Clinic and the senior author of the study. “This large number highlights how these operations have kept a substantial part of our population mobile despite severe arthritis, something that wouldn’t have been possible before these technologies were available. These relatively high prevalence estimates also highlight the significant ongoing need to care for all of the patients with total hip and knee replacement. These prevalence estimates are within the same ballpark as coronary heart disease, and much higher than heart failure or stroke. To put these numbers in perspective, there are roughly one and a half times as many people living with a hip or knee replacement in the US as people living with heart failure.”

Individuals with total hip and knee replacement often are complex patients with multiple chronic conditions,” added William A. Jiranek, MD, Professor of Orthopaedics at Virginia Commonwealth University School of Medicine. “They all need continuing medical attention and some need further surgical attention over the years of having a replacement. As “there are no guidelines to define long-term management of these individuals … our prevalence estimates are vital to agencies charged with planning for the provision of health care services.”

In two related studies presented at the annual meeting—“Trends in Total Hip Arthroplasty in the United States: The Shift to a Younger Demographic” and “Trends in Total Knee Arthroplasty in the United States: Understanding the Shift to a Younger Demographic”—researchers conducted a retrospective review of 2000 to 2009 hospital discharge data on TKR and THR patients from the Nationwide Inpatient Sample (NIS) Healthcare Cost and Utilization Project (HCUP). Researchers looked at procedural rates, gender, race, age, payer type, length of stay (LOS), discharge disposition, and revision burden for each year, stratified by age. US National Census data was used to calculate rates for each procedure per 100,000 US populations within each age group.

Among the study findings:

• The incidence of TKR increased by 120% from 2000 to 2009: 188% for patients ages 45 to 64, and 89% for patients ages 65 to 84. The incidence of THR increased 73% from 2000 to 2009: 123% for patients ages 45 to 64, and 54% for ages 65 to 84.

• The number of revision total knee replacement (RTKR) procedures increased 133%, and the number of revision total hip replacement (RTHR) procedures by 27%.

• The increase in TKR and THR patients is primarily due to “the disproportionate growth in the rate of utilization among younger patients, and secondarily by overall population growth.”

• Medicare was the primary payer for 63.3% of all TKRs and 58.2% of THRs in 2000, and 54.7% of TKRs and 52.8% of THRs in 2009.

• The proportion of TKR patients discharged with home health care increased from 19.1% in 2000 to 40.5 % in 2009; and the number of THR patients, from 18.9% in 2000 to 40.8% in 2009.

• Race and gender distribution have remained relatively stable for TKR, RTKR, THR, and RTHR.

“Our data demonstrate that increases in the number of primary and revision knee and hip arthroplasties have been driven predominately by increased procedural rates, as opposed to population demographics,” said lead study author Jacob M. Drew, MD, of the University of Massachusetts Medical School.

In addition, “while shifts in age strata seem to be ongoing, race and gender distribution have remained relatively stable for both TKR and THR,” said Dr. Drew. “This suggests that well-documented racial disparity in total joint replacement (TJR) persists, and that there remains a substantial population in whom TJR is underutilized.”

NEW ORLEANS—More than 7 million Americans are living with an artificial knee (4.7 million) or hip (2.5 million), which may have significant future implications in terms of the need for ongoing patient care, according to new research presented at the 2014 Annual Meeting of the American Academy of Orthopaedic Surgeons (AAOS). Two related studies also found a growing incidence of adults younger than age 65 undergoing total knee replacement (TKR) and total hip replacement (THR) surgeries, and a potential underutilization of these procedures in some segments of the population.

While numerous studies have quantified the incidence rate of TKR and THR in the United States, there is very little information about the number of patients actually living with a prosthetic knee or hip. In a presentation titled “Prevalence of Total Hip (THA) and Total Knee (TKA) Arthroplasty in the United States,” researchers reviewed THR and TKR incidence rates, mortality rates, and relative mortality rates (the difference in survival between THR and TKR patients and the general population) over a 40-year period to estimate 2010 prevalence rates according to age, sex, and time since surgery.

Among the study findings:

• Approximately 0.8% of Americans are living with a hip replacement and 1.5% with a knee replacement.

• More women are living with prosthetic hips and knees than men.

• Prevalence of THR and TKR among adults age 50 and older is as high as 2.3% and 4.6%, respectively.

• The prevalence of THR rises to nearly 6% by 80 years of age. The prevalence of TKR rises to nearly 10% by 80 years of age.

• The states with the highest number of THR and TKR patients are California, Florida, and Texas; the two states with the lowest numbers are Alaska and Hawaii.

“This study shows that around 7 million Americans have a hip or knee replacement,” said Daniel Berry, MD, Professor of Orthopaedics at Mayo Clinic and the senior author of the study. “This large number highlights how these operations have kept a substantial part of our population mobile despite severe arthritis, something that wouldn’t have been possible before these technologies were available. These relatively high prevalence estimates also highlight the significant ongoing need to care for all of the patients with total hip and knee replacement. These prevalence estimates are within the same ballpark as coronary heart disease, and much higher than heart failure or stroke. To put these numbers in perspective, there are roughly one and a half times as many people living with a hip or knee replacement in the US as people living with heart failure.”

Individuals with total hip and knee replacement often are complex patients with multiple chronic conditions,” added William A. Jiranek, MD, Professor of Orthopaedics at Virginia Commonwealth University School of Medicine. “They all need continuing medical attention and some need further surgical attention over the years of having a replacement. As “there are no guidelines to define long-term management of these individuals … our prevalence estimates are vital to agencies charged with planning for the provision of health care services.”

In two related studies presented at the annual meeting—“Trends in Total Hip Arthroplasty in the United States: The Shift to a Younger Demographic” and “Trends in Total Knee Arthroplasty in the United States: Understanding the Shift to a Younger Demographic”—researchers conducted a retrospective review of 2000 to 2009 hospital discharge data on TKR and THR patients from the Nationwide Inpatient Sample (NIS) Healthcare Cost and Utilization Project (HCUP). Researchers looked at procedural rates, gender, race, age, payer type, length of stay (LOS), discharge disposition, and revision burden for each year, stratified by age. US National Census data was used to calculate rates for each procedure per 100,000 US populations within each age group.

Among the study findings:

• The incidence of TKR increased by 120% from 2000 to 2009: 188% for patients ages 45 to 64, and 89% for patients ages 65 to 84. The incidence of THR increased 73% from 2000 to 2009: 123% for patients ages 45 to 64, and 54% for ages 65 to 84.

• The number of revision total knee replacement (RTKR) procedures increased 133%, and the number of revision total hip replacement (RTHR) procedures by 27%.

• The increase in TKR and THR patients is primarily due to “the disproportionate growth in the rate of utilization among younger patients, and secondarily by overall population growth.”

• Medicare was the primary payer for 63.3% of all TKRs and 58.2% of THRs in 2000, and 54.7% of TKRs and 52.8% of THRs in 2009.

• The proportion of TKR patients discharged with home health care increased from 19.1% in 2000 to 40.5 % in 2009; and the number of THR patients, from 18.9% in 2000 to 40.8% in 2009.

• Race and gender distribution have remained relatively stable for TKR, RTKR, THR, and RTHR.

“Our data demonstrate that increases in the number of primary and revision knee and hip arthroplasties have been driven predominately by increased procedural rates, as opposed to population demographics,” said lead study author Jacob M. Drew, MD, of the University of Massachusetts Medical School.

In addition, “while shifts in age strata seem to be ongoing, race and gender distribution have remained relatively stable for both TKR and THR,” said Dr. Drew. “This suggests that well-documented racial disparity in total joint replacement (TJR) persists, and that there remains a substantial population in whom TJR is underutilized.”