ArticlePDF AvailableLiterature Review

Does long-distance running cause osteoarthritis?

Authors:
  • Maryland College of Osteo Med at Morgan State (Proposed)

Abstract

There is a dose-response relationship between physical activity and the reduced risk of some diseases (eg, cardiovascular disease, diabetes mellitus). At a certain "dose," however, the reduced risk of some diseases may be offset by an increased risk of injury and osteoarthritis. Osteoarthritis can be caused by trauma to, or overuse of, the joints. Sports injuries often occur as a result of dysfunctions in balance or the musculoskeletal system operating in nonneutral mechanics. It is unclear if long-distance running causes the knee and hip joints to deteriorate. The results of animal studies reveal a pattern of increased incidence of arthritis in these joints when there is a history of injury or use in atypical environments (eg, laboratory settings). Human studies show an increase in radiographic evidence of osteoarthritis in endurance sports athletes, but no related increase in symptoms reported. Although there are not currently enough data to give clear recommendations to long-distance runners, it appears that long-distance running does not increase the risk of osteoarthritis of the knees and hips for healthy people who have no other counterindications for this kind of physical activity. Long-distance running might even have a protective effect against joint degeneration. The authors recommend further study.
1
Does Long-Distance Running Cause
Osteoarthritis?
Tyler Childs Cymet, DO
Vladimir Sinkov, MD
Exercise is thought to enhance our health. There is a dose-
response relationship between physical activity and the reduced
risk of some diseases (eg, cardiovascular disease, dia-
betes). At a certain çdose,å however, the reduced risk of
some diseases may be offset by an increased risk of injury
and osteoarthritis. Osteoarthritis can be caused by trauma
to, or overuse of, the joints. Sports injuries often occur as
a result of dysfunctions in balance or the musculoskeletal
system operating in nonneutral mechanics. It is unclear if
long-distance running causes the knee and hip joints to
deteriorate. The results of animal studies reveal a pattern
of increased incidence of arthritis in these joints when
there is a history of injury or use in atypical environ-
ments (eg, laboratory settings). Human studies show an
increase in radiographic evidence of osteoarthritis in
endurance sports athletes, but no related increase in prob-
lems reported[AQ 1: Please specify what you mean by
“problems reported.” Pain? Disability? Please indicate.
Thank you. —RJF]. Although there are not currently enough
data to give clear recommendations to long-distance runners,
it appears that long-distance running does not increase the
risk of osteoarthritis of the knees and hips for healthy people
who have no other counterindications for this kind of phys-
ical activity. Long-distance running might even have a pro-
tective effect against joint degeneration. The authors rec-
ommend further study.
P
hysical activity is important in maintaining health. Long-
distance and marathon running are relatively safe sports.1
Anecdotally, however, it is felt that “Today’s runners are
tomorrow’s cyclists”—not because of a “natural progres-
sion” from one sport to the other, but as a result of joint
injury.
Is there a causal relationship between running and
osteoarthritis? The current data are based on small studies,
and their results are often unclear. People engaged in sports
or other physically demanding activities are known to be at
an increased risk of osteoarthritis in the joints they use most
(eg, knees and hips in soccer players, hands in boxers, lower
backs in construction workers). Part of this seeming corre-
lation can be explained by increased risk of joint injury.2It
would also seem logical that these groups would be pre-
disposed to osteoarthritis from overuse injuries, and not
necessarily from trauma.
Osteoarthritis is generally divided into primary
osteoarthritis, related to age and genetics, and secondary
osteoarthritis, which is associated with a history of any kind
of joint injury (eg, trauma, infection, surgery, mineral depo-
sition, autoimmune disorders). Joint trauma can be acute or
chronic, and pain intensity can be severe or mild. The trauma
may be ligamentous, meniscal, or muscular in origin. Because
of nonpathogenic but highly repetitive loading, overuse
injuries may be considered a mild, chronic joint trauma.
Such use is thought, with time, to deplete the joint of the
lubricating glycoproteins, disrupt the collagen network,
slowly wear away the cartilage, and cause numerous
microfractures in the underlying bones[AQ 2: Please provide
references in support of this statement. Thank you. —RJF].
Animal Studies
Researchers conducting animal studies have attempted to
simulate long-term stress on weight-bearing joints to determine
how such activities might damage the joint. In sheep studies,
Radin and colleagues3have shown that 4 hours of walking on
a concrete surface resulted in signs of osteoarthritis.
More recent canine studies by Kiviranta et al4,5 demon-
strated that moderate running improved the joint condition
in terms of cartilage thickness and glycosaminoglycan content,
whereas more strenuous running reversed those benefits and
was detrimental to joint health. The latter finding was further
supported in a study of laboratory rats by Pap and colleagues,6
in which the animals were subjected to “strenuous running”
(30 km within 6 weeks). Researchers found histologic evi-
dence of osteoarthritis in all of the exercised group and none
in the resting controls.6
The findings of Lapvetelainen et al7differed from those
in the previously noted studies, however.3–6 Researchers cre-
ated mice with heterozygous inactivation of gene coding for
type 2 procollagen and subjected them and controls to lifelong
voluntary wheel-running exercise. As expected, the exercised
knockout mice had more knee osteoarthritis than resting con-
trols[AQ 3: I am not familiar with the term “knockout” in this
context. Is this standard technical terminology? (It sounds
“jargony.”) Please advise. —RJF]. However, running
knockout mice had less knee osteoarthritis than sedentary
mice. There was no difference in prevalence rates for
osteoarthritis between exercised mice and sedentary controls,
but increased prevalence of knee osteoarthritis was seen in
exercised and control mice with high body weight. Lapvete-
lainen et al7demonstrated that physical activity does not pre-
dispose normal mice to osteoarthritis and might, in fact, pro-
tect injured mice from the disease.
Although the results of more recent studies conflict with
their predecessors, there seems to be a pattern: intrinsic injury
or excessive exercise seems to lead to a higher incidence of
osteoarthritis, whereas moderate exercise was either non-
contributory in joint degeneration or it was found to be ben-
eficial in decreasing the risk of osteoarthritis in animals.8[AQ 4:
Edits okay? Original read: “Intrinsic injury or excessive
exercise seem to lead to more OA, whereas moderate exer-
cise was either beneficial or noncontributory in decreasing
the risk of OA in animals.” Please advise: Y/N. —RJF]
There are many limitations, however, to making such a
2
general statement or applying this principle to humans. The
animals studied varied greatly among these experiments; the
anatomy, biomechanics of joint loading, muscle strength, and
ability to recover from minor joint injuries varies greatly from
sheep and dogs to mice and rats. Furthermore, though some
animals were subjected to the same joint loads as they would
experience in nature (eg, running), some experimental animals
were required to exercise in a laboratory environment to
which they were not adapted (eg, walking on concrete).3
Finally, the measurements of osteoarthritis varied from gross,
to histologic, to biochemical[AQ 5: Please put reference num-
bers 2-6 next to each measurement type (eg, gross,3histo-
logic,4-5, to biochemical6,7). Thank you. —RJF]. Even if all of
these confounding factors were controlled for, it is still ques-
tionable whether the results would be generalizable to
humans.
Human Studies
Numerous studies have investigated the association of pro-
longed running and osteoarthritis of the knee and hip. Unfor-
tunately, the evidence from these studies is conflicting, with
some researchers saying that running is not associated with
increased prevalence of osteoarthritis,9–16 while others indicate
that running can increase the risk of knee and hip
osteoarthritis.17–19 All of the studies, however, are retrospective;
many have few subjects, fail to separate runners from other
athletes14,18; or neglect to stratify the subjects by the amount
of running or history of injuries to the lower extremities; and
many study either professional athletes or amateurs[AQ 6: As
in AQ #5, please put reference numbers next to each item in
this list. —RJF]. In addition, some studies were done in other
countries, making it hard to generalize their results to the
population in the United States.14–15,20 Finally, researchers have
used different diagnostic criteria to evaluate the extent of
osteoarthritis in subjects.
In a 1973 study, Marti and colleagues17 conducted a ret-
rospective review of male subjects who were former athletes
(long-distance runners, n=27; bobsleigh riders, n=9) or normal,
healthy nonathlete controls (n=23). Subjects were then reex-
amined 15 years later. Researchers17 found that high-intensity
running (ie, 97 km per week) was associated with a signifi-
cantly higher incidence of radiographic evidence of
osteoarthritis of the hip. The limitations of the study included
atypically high intensity of running, small sample size, lack of
correlation with history of injury to the hip joint, and use of
radiographic evidence as the sole measure of osteoarthritis.
A study by Spector and colleagues18 in the United
Kingdom investigated osteoarthritis in women who were
former elite long-distance runners and tennis players. Spector
et al18 found a two- to threefold increase in the incidence of
radiographic osteoarthritis in the study group even when
subjects were controlled for age. The authors18 found similar
rates of reported knee pain between the former athletes and
controls subjects, however. This study also had a low number
of athletic participants (n=81), combined runners and tennis
players into one group, and looked at women only. In addi-
3
tion, the study methods assumed that athletes and nonathletes
would report pain similarly.
The most recent study implicating running as a cause of
osteoarthritis was conducted by Cheng et al.19 The study
involved nearly 17,000 patients seen at the Cooper Clinic in
Dallas, Tex, from 1970 to 1995. All patients were later con-
tacted by mail and asked to report on physician-diagnosed ill-
nesses and conditions by return survey. Researchers19 found
significantly higher incidence of osteoarthritis in men (aged
20–49 years) who were involved in high levels of physical
activity (ie, walking or running more than 20 miles per week).
Although this 10-year study had a very large sample size
with subjects from a variety of age groups (range 20 to 87
years), the study was limited in that the population was demo-
graphically uniform (ie, well-educated, non-Hispanic white
men of high socioeconomic status) and did not gather data on
subjects’ occupational activities (eg, kneeling, squatting, car-
rying heavy loads) or history of physical trauma, and relied
solely on self-reported data during follow up.
In another longitudinal study, Sohn and colleagues9com-
pared 504 former college varsity cross-country runners with
a control group of 284 former college swimmers. Subjects
were observed for an average period of 25 years. In particular,
researchers9noted reports of pain in the hips and knees as well
as any history of surgical procedures for relief of that pain
(ie, evidence of the presence of osteoarthritis). In the group of
college swimmers, no data were gathered on the swimming
strokes subjects most commonly used in competition. Sohn et
al9found that moderate long-distance running (25.4 miles
per week on average) was not associated with higher incidence
of osteoarthritis of the hip or knee. In addition, there was also
no evidence to suggest that higher weekly averages for dis-
tance or more total years running were associated with a
higher incidence of osteoarthritis. The study9had a large
sample size, a long average follow-up time, and good mea-
sures for incidence of osteoarthritis.
Kujala and colleagues14–15 have conducted many studies
on the effects of running on the human musculoskeletal
system. In one of their articles, Kujala et al14 described the
incidence of knee osteoarthritis in former athletes in various
sports. Runners were not found to have an increased inci-
dence of knee osteoarthritis. However, the study14 had few par-
ticipants (N=117; long-distance runners, n=28) and included
only professional male athletes from Finland.
In another study, Kujala et al15 compared men who were
master orienteering runners with matched nonsmoking con-
trol subjects. Even though researchers found a higher inci-
dence of knee osteoarthritis in the runners (17% vs 10.6%,
P=.025), they attributed this difference to a higher likelihood
of knee injuries in the athletes and to referral bias.
One of the most well-known American studies on run-
ning and osteoarthritis was published by Lane et al12 in 1993.
These researchers looked at a large population of members of
the 50-Plus Runners’ Association and, after a careful selec-
tion process, narrowed down their sample to 33 matched
pairs of long-term long-distance runners and non-running
4
controls living in Stanford, Calif. All 66 subjects underwent a
rheumatologic examination, completed annual questionnaires,
and received radiographs of their joints during the 5-year
study period. The study12 showed no difference in the inci-
dence of osteoarthritis in runners and nonrunners. The limi-
tations of this study included a small sample size and a lim-
ited follow-up time. However, in a subsequent study, Lane and
colleagues16 reported that at 9-year follow-up, the results were
the same; there was no difference in the incidence and pro-
gression of knee and hip osteoarthritis in runners and non-
runners.
Fries and colleagues13 studied 451 members of a run-
ners’ club and 330 community controls aged 50 to 72 years,
observing these 781 subjects during an 8-year study period.
The runners had lower mortality rates and a lower incidence
of musculoskeletal disabilities and osteoarthritis. The study,13
however, looked at overall disability rather than osteoarthritis
in particular.
Advising Patients
Most acute injuries in runners are from overuse.[AQ 7: Please
insert reference. —RJF] In addition, running while injured
seems to promote poor body mechanics, functioning as a
major contributor to chronic injuries.21
A 1 mile run may require anywhere from 1000 to 1500
strides from the runner. In long-term, repetitive strain, the
body responds by increasing water and proteoglycan con-
tent in the joint fluid while periarticular ligaments and sup-
porting muscles undergo adaptive hypertrophy.
In properly trained athletes, who have increased exercise
intensity and duration slowly, localized pain or problems
with performing to their regular expectations often precede
injury to a specific joint. Medical advice to a runner should take
into account the individual’s running style and ability, as well
as body size. The greater the body mass index, often the
greater the radiographic evidence of osteoarthritis noted in the
joints.22
Apophyseal injuries are a greater risk for athletes aged
between 16 and 25 years.23 Physicians should carefully con-
sider patient age, size, and biomechanics when providing
advice to long-distance runners.
The rate-limiting step in long-distance running is more
energy related, with amounts of glycogen in the muscle avail-
able for breakdown necessary for sustained exercise, and not
swelling, or bone and joint dysfunction.24
Conclusion
Although the existing evidence on whether long-term long-
distance running causes osteoarthritis is currently insufficient
for researchers to draw unequivocal conclusions, the pre-
ponderance of data seems to indicate that moderate levels of
running do not increase the risk of osteoarthritis of the knees
and hips for healthy people and that this activity might even
have a protective effect. A history of injury–from overuse or
acute trauma as a result of running, excessive running, intrinsic
anatomical instability in the joints, or a high body mass
5
index–can accelerate the onset of osteoarthritis and cause dis-
ability, however. It is important that people considering a
new exercise regimen seek a physical evaluation by a sports
medicine physician and that they learn proper training
methods so that they may prevent joint injury.
The risks of running as noted should be weighed against
the tremendous benefits of this activity to the other body sys-
tems. Running has been shown to decrease the risk of car-
diovascular disease, diabetes, and depression[AQ 8: As with
AQ #5, please insert reference numbers after each item in this
list of benefits. Thank you. —RJF]. This kind of physical
activity has also been shown to help with weight control, to
improve bone density, and to decrease mortality[AQ 9: Please
continue inserting references as requested in AQ #5. —
RJF].20,25–27
To better understand the effects of running on the human
musculoskeletal system, more studies are needed. Such studies
would ideally follow cohorts of runners and controls prospec-
tively using validated diagnostic criteria28 and would use a
large sample size[AQ 10: Source added. Okay to include?
Please advise: Y/N. Also, did you have other references in
mind? Thank you. —RJF]. Subjects at various levels of run-
ning should be included, with controls for confounding fac-
tors such as sex, body weight, history of injury to the lower
extremities, family history of osteoarthritis, and occupational
risks.29
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From the Johns Hopkins School of Medicine (Cymet) and Union Memorial Hos-
pital (Sinkov), both in Baltimore, Md.
Address correspondence to: Tyler Cymet, DO, 6 Tyler Falls Ct, Apt A, Bal-
timore, MD 21209-5227.
E-mail: tcymet@lifebridgehealth.org
7
... In 2006, Cymet T and Sinkov V [4], stated that in reasonable amounts, physical activity can reduce the risk of developing certain diseases. However, when the amount of physical activity surpasses the reasonable limit, the protective effect may be offset with an increased risk of injury or osteoarthritis [4]. ...
... In 2006, Cymet T and Sinkov V [4], stated that in reasonable amounts, physical activity can reduce the risk of developing certain diseases. However, when the amount of physical activity surpasses the reasonable limit, the protective effect may be offset with an increased risk of injury or osteoarthritis [4]. This was the initial thought; however, this study found that that was not the case [4]. ...
... However, when the amount of physical activity surpasses the reasonable limit, the protective effect may be offset with an increased risk of injury or osteoarthritis [4]. This was the initial thought; however, this study found that that was not the case [4]. Studies were conducted on both animal subjects and human subjects. ...
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... The comparison of sports like running and soccer reflects that soccer has a higher injury incidence and O.A rate as compared to running which is considered a safe sport now. 9,12 This systematic review was conducted to synthesize the evidence on the quantitative association between participation in specific sports and the occurrence of Knee OA. This systematic review will also analyze the effect of sports injuries on knee OA. ...
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... This immediate T2 response recovers rapidly after 30 min up to a few hours [78][79][80][81] . However, we could not detect such primary T2* decreases at any MI (t1-t3), since our first data were acquired at t1 after a distance run of 962-1,325 km (stage [14][15][16][17][18][19][20], at which time the effects of long-distance running dominate (masked) the immediate T2-response. ...
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Nearly nothing is known about the consequences of ultra-long-distance running on knee cartilage. In this mobile MRI field study, we analysed the biochemical effects of a 4,486 km transcontinental multistage ultra-marathon on femorotibial joint (FTJ) cartilage. Serial MRI data were acquired from 22 subjects (20 male, 18 finisher) using a 1.5 T MR scanner mounted on a 38-ton trailer, travelling with the participants of the TransEurope FootRace (TEFR) day by day over 64 stages. The statistical analyses focused on intrachondral T2* behaviour during the course of the TEFR as the main outcome variable of interest. T2* mapping (sagittal FLASH T2* weighted gradient echo) is a validated and highly accurate method for quantitative compositional cartilage analysis of specific weightbearing areas of the FTJ. T2* mapping is sensitive to changes in the equilibrium of free intrachondral water, which depends on the content and orientation of collagen and the proteoglycan content in the extracellular cartilage matrix. Within the first 1,100 km, a significant running load-induced T2* increase occurred in all joint regions: 44.0% femoral-lateral, 42.9% tibial-lateral, 34.9% femoral-medial, and 25.1% tibial-medial. Osteochondral lesions showed no relevant changes or new occurrence during the TEFR. The reasons for stopping the race were not associated with knee problems. As no further T2* elevation was found in the second half of the TEFR but a decreasing T2* trend (recovery) was observed after the 3,500 km run, we assume that no further softening of the cartilage occurs with ongoing running burden over ultra-long distances extending 4,500 km. Instead, we assume the ability of the FTJ cartilage matrix to reorganize and adapt to the load.
... The annual incidence of musculoskeletal injury is as high as 90% in people preparing for a marathon, and knee joint injuries are the most common [3][4][5]. At present, specialists have different opinions on the impact of marathons on the knee joint cartilage [6][7][8]. Some believe that the excessive stress during the marathon and training may exceed the load capacity of the knee joint cartilage, which may lead to cartilage damage and secondary knee osteoarthritis (KOA) [9,10]. ...
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To evaluate changes in knee articular cartilage of amateur marathon runners using magnetic resonance imaging T2 relaxation time mapping. T2 mapping was performed in 18 non-professional male marathon runners 48 h before and 72 h after a marathon. Bulk and zonal tibiofemoral T2 mapping were assessed. T2 mapping values of the left knees (LK) decreased after competition (48.45±25.08 versus 39.75±18.91 ms), while those of the right knees (RK) were similar before and after the marathon. Significant increases in mean T2 relaxation times were observed in the RK medial femoral condyle (42.14±8.96 versus 53.63±3.664 ms). There were significant decreases in T2 relaxation time in the LK medial tibial plateau (50.01±30.25 versus 33.99±7.25 ms), LK lateral tibial plateau (44.64±19.84 versus 29.62±9.76 ms), LK lateral femoral condyle (54.72±32.94 versus 44.75±16.61 ms), and RK lateral tibial plateau (42.93±16.91 versus 35.51±16.20 ms). No significant changes were observed in the LK medial femoral condyle, RK medial tibial plateau, and femoral condyle. Regional analyses showed lower T2 mapping values in the L2, R2, L5, R5, L8, and R8 points on both knees after competition. Changes in T2 mapping values can reflect alterations in cartilage structures. As an extreme endurance sport, marathons can damage the local cartilage of knee joints of non-professional marathon athletes shortly after exercise. However, this effect is small and probably not clinically relevant.
... This knowledge helps estimating the potential consequences of exercise including recreational and professional sports. A matter of debate is to which degree running may increase the risk of developing OA (Cymet and Sinkov 2006;Urquhart et al. 2011). It is currently believed that high-impact physical activity, including running, can increase the risk of developing OA (Kujala et al. 1995;McAlindon et al. 1999;Alentorn-Geli et al. 2017), while some studies also describe protective effects (Fries et al. 1994;Rogers et al. 2002;Alentorn-Geli et al. 2017). ...
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PurposeTo investigate acute changes in biochemical markers of bone and cartilage turnover in response to moderate intensity exercise with and without joint impact in healthy human subjects.MethodsA randomized, cross-over, exploratory, clinical study was conducted. Twenty healthy subjects with no history of joint trauma completed 30 min interventions of standardized moderate intensity cycling and running as well as a resting intervention 1 week apart. Blood samples were taken immediately before, four times after exercise and again the next day. Urine was sampled, before, after and the next day. On the day of rest, samples were taken at timepoints similar to the days of exercise. Markers of type I (CTX-I), II (C2M, CTX-II) and VI (C6M) collagen degradation, cartilage oligomeric matrix protein (COMP) and procollagen C-2 (PRO-C2) was measured. Trial registration number: NCT04542655, 02 September 2020, retrospectively registered.ResultsCTX-I was different from cycling (4.2%, 95%CI: 0.4–8.0%, p = 0.03) and resting (6.8%, 95%CI: 2.9–10.7%, p = 0.001) after running and the mean change in COMP was different from cycling (10.3%, 95%CI: 1.1–19.5%, p = 0.03), but not from resting (8.6%, 95%CI: − 0.7–17.8%, p = 0.07) after running. Overall, changes in other biomarkers were not different between interventions.Conclusion In this exploratory study, running, but not cycling, at a moderate intensity and duration induced acute changes in biomarkers of bone and cartilage extra-cellular matrix turnover.
... Interessant erscheint auch die Beobachtung, dass Spitzenathleten, obwohl sie teilweise doch vermehrt Arthrosezeichen haben, in der klinischen Symptomatik deutlich besser abschneiden, als Patienten mit ähnlichen radiologischen Arthrosezeichen, die nicht Sport betrieben haben. Für moderates und mittelmäßig intensives Training konnten verschiedene Autoren feststellen, dass kein erhöhtes Arthroserisiko vorliegt und sogar eine bessere Gelenkfunktion zu erwarten ist [31]. Die Umfänge die hier angegeben werden, liegen ungefähr bei 5 h oder 40 km/Woche, wo auch nach langjährigen (5-9 Jahren) Beobachtungen keine vermehrte Arthrose festgestellt werden konnte. ...
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Zusammenfassung Hintergrund Arthrose – die Degeneration von Gelenken – ist ein weit verbreitetes Problem durch alle Bevölkerungsschichten, das im zunehmenden Alter vermehrt auftritt und die häufigste Ursache für mobilitätseinschränkende Schmerzen am Bewegungsapparat ist. Etwa 70–80 % der über 70-Jährigen zeigen Zeichen einer Gelenksdegeneration. Insgesamt sind bis zu 25 % der Gesamtbevölkerung davon betroffen, aufgrund der generellen Alterung der Bevölkerung mit steigender Tendenz. Die Inzidenz der Arthrose steigt aber schon ab dem 40 Lebensjahr, wobei besonders posttraumatische und sekundäre Arthroseformen zum Tragen kommen. Anspruch Der Wunsch nach hoher Mobilität und Sport zieht sich als Phänomen ebenfalls durch alle Altersgruppe. Dies ist mit hohen Gelenkbelastungen verbunden und stellt damit eine große Herausforderung an vor allem früh degenerativ veränderte Gelenksstrukturen dar. In diesem Zusammenhang ist der orthopädisch tätige Arzt gefordert, die Belastbarkeit von geschädigten Gelenken abzuschätzen und so früh wie möglich präventive Schritte sowie gegebenenfalls konservative Therapien einzuleiten, um die Progression der Arthrose zu verhindern und damit den eventuell notwendigen Gelenkersatz möglichst weit nach hinten zu schieben.
... The sustained beneficial effect of running on knees at 6 months after the marathon implies that running may help in reducing the chances of osteoarthritis in the long term. Few other (non-MRI) studies suggested running may protect the knee joint from osteoarthritis [22][23][24][25]. Any remaining bone marrow oedema-like signal appearing post-marathon is expected to resolve within 2 years [16,[26][27][28][29][30]. ...
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Objective To evaluate changes in the knee joints of asymptomatic first-time marathon runners, using 3.0 T MRI, 6 months after finishing marathon training and run.Materials and methodsSix months after their participation in a baseline study regarding their knee joints, 44 asymptomatic novice marathoners (17 males, 27 females, mean age 46 years old) agreed to participate in a repeat MRI investigation: 37 completed both a standardized 4-month-long training programme and the marathon (marathon runners); and 7 dropped out during training (pre-race dropouts). The participants already underwent bilateral 3.0 T MRIs: 6 months before and 2 weeks after their first marathon, the London Marathon 2017. This study was a follow-up assessment of their knee joints. Each knee structure was assessed using validated scoring/grading systems at all time points.ResultsTwo weeks after the marathon, 3 pre-marathon bone marrow lesions and 2 cartilage lesions showed decrease in radiological score on MRI, and the improvement was sustained at the 6-month follow-up. New improvements were observed on MRI at follow-up: 5 pre-existing bone marrow lesions and 3 cartilage lesions that remained unchanged immediately after the marathon reduced in their extent 6 months later.No further lesions appeared at follow-up, and the 2-week post-marathon lesions showed signs of reversibility: 10 of 18 bone marrow oedema-like signals and 3 of 21 cartilage lesions decreased on MRI.Conclusion The knees of novice runners achieved sustained improvement, for at least 6 months post-marathon, in the condition of their bone marrow and articular cartilage.
Article
Background Osteogenesis Imperfecta (OI) is a genetic disease characterized by skeletal fragility. Collagen type 1 is found in many tissues and collagen abnormalities may result in organ specific symptomatology. Musculoskeletal pain is a known issue for patients with OI, osteoarthritis (OA) can be a likely cause. Only few studies have investigated the relationship between OI and OA but demonstrated a greater propensity in OI patients to develop rapidly progressing OA. Therefore, we wanted to investigate if OA is more frequent in patients with OI compared to the general population. Objective To evaluate the risk of osteoarthritis in patients with OI. Design A Danish nationwide, population-based and register-based longitudinal open cohort study. Participants From 1977 to 2019, all patients registered with an OI diagnosis and a reference population matched on age and sex 5:1. Measurements Sub-hazard ratios for any, hip, and knee osteoarthritis comparing the OI cohort to the reference population. Results We identified 907 patients with OI (493 women) and included 4,535 patients in the reference population (2,465 women). The Sub Hazard Ratio was 2.20 [95% CI 1.73-2.79] for any osteoarthritis with 11.4% of the OI population and 5.4% of the reference population being registered. We found lower incidences of upper extremity joint OA compared to lower joint OA, but upper extremity joint OA was significantly more frequent in the OI population 2.1% vs 0.6%, SHR 3.19 [95% CI 1.78-5.70]). Conclusion Patients with OI have a higher risk of OA than the reference population. Miniabstract Osteogenesis Imperfecta (OI) is a hereditary connective tissue disorder with skeletal fragility and extraskeletal manifestations. Osteoarthritis is a frequent joint disease and the incidence increases with age. In a population-register-based study, the risk of osteoarthritis was higher in patients with OI at an earlier age compared to a reference population.
Article
Objective: To study the effect of long-distance running on the morphological and T2* assessment of knee cartilage. Methods: 3D-DESS and T2* mapping was performed in 12 amateur marathon runners (age: between 21 and 37 years) without obvious morphological cartilage damage. MRI was performed three times: within 24 h before the marathon, within 12 h after the marathon, and after a period of convalescence of two months. An automatic cartilage segmentation method was used to quantitatively assessed the morphological and T2* of knee cartilage pre- and post-marathon. The cartilage thickness, volume, and T2* values of 21 sub-regions were quantitatively assessed, respectively. Results: The femoral lateral central (FLC) cartilage thickness was increased when 12-h post-marathon compared with pre-marathon. The tibial medial anterior (TMA) cartilage thickness was decreased when 2 months post-marathon compared with pre-marathon. The tibial lateral posterior (TLP) cartilage volume was increased when 12-h post-marathon compared with pre-marathon. The cartilage T2* value in most sub-regions had the upward trend when 12-h post-marathon and restored trend when 2 months post-marathon, compared with pre-marathon. The femoral lateral anterior (FLA) and TMA cartilage volumes were decreased 2 months post-marathon compared with pre-marathon. Conclusions: The marathon had some effects on the thickness, volume, and T2* value of the knee cartilages. The thickness and volume of knee cartilage in most sub-regions were without significantly changes post-marathon compared with pre-marathon. T2* value of knee cartilage in most sub-regions was increased right after marathon and recovered 2 months later. The TLP and TMA subregions needed follow-up after marathon. Advances in knowledge: The morphological and T2* changes of knee cartilage after marathon were evaluated by MRI and automatic segmentation software. This study was the first to use cartilage automatic segmentation software to evaluate the effects of marathon on the morphology and biochemical components of articular cartilage, and to predict the most vulnerable articular cartilage subregions, for the convenience of future exercise adjustment and the avoidance of sports cartilage injury.
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To determine the effects of regular long distance running on the state of the hips in later life. Retrospective study of a cohort of elite athletes and a group of normal, healthy, untrained controls examined 15 years after initial testing. Research project at school for physical education and sports. 27 Former long distance runners (mean age 42), nine former bobsleigh riders (mean age 42), and 23 normal, healthy, untrained men (mean age 35) who had been examined in 1973 and who agreed to re-examination in 1988. Radiological evidence of degenerative hip disease in 1988. Physiological and exercise characteristics of all subjects had been recorded in 1973, and in 1988 these measurements were repeated together with radiological examination of the hips. An additive radiological index of hip disease based on grades of subchondral sclerosis, osteophyte formation, and joint space narrowing was significantly increased among runners as compared with bobsleigh riders and untrained controls. After adjustment for age the significant effect of type of sports activity remained (p = 0.032). In multivariate analyses age and milage run in 1973 (97 km/week) emerged as independent, significant, and positive predictors of radiological signs of degenerative hip disease in 1988 (p = 0.017 and p = 0.024 respectively). Among runners alone running pace in 1973 rather than milage run was the stronger predictor of subsequent degenerative hip disease. The milage run in 1988 was not particularly predictive of the radiological index, but endurance in 1988 was inversely related to degenerative hip disease seen radiologically. Long term, high intensity, high milage running should not be dismissed as a potential risk factor for premature osteoarthritis of the hip.
Article
Objective. To estimate the risk of osteoarthritis (OA) of the hip and knee due to long-term weight-bearing sports activity in ex–elite athletes and the general population. Methods. A retrospective cohort study was conducted of 81 female ex–elite athletes (67 middle- and long-distance runners, and 14 tennis players), currently ages 40–65, recruited from original playing records, and 977 age-matched female controls, taken from the age–sex register of the offices of a group general practice in Chingford, Northeast London, England. The definition of OA included radiologic changes (joint space narrowing and osteophytosis) in the hip joints, patellofemoral (PF) joints, and tibiofemoral (TF) joints. Results. Compared with controls of similar age, the ex-athletes had greater rates of radiologic OA at all sites. This association increased further after adjustment for height and weight differences, and was strongest for the presence of osteophytes at the TF joints (odds ratio [OR] 3.57, 95% confidence interval [95% CI] 1.89–6.71), at the PF joints (OR 3.50, 95% CI 1.80–6.81), narrowing at the PF joints (OR 2.97, 95% CI 1.15–7.67), femoral osteophytes (OR 2.52, 95% CI 1.01–6.26), and hip joint narrowing (OR 1.60, 95% CI 0.73–3.48), and was weakest for narrowing at the TF joints (OR 1.17, 95% CI 0.71–1.94). No clear risk factors were seen within the ex-athlete groups, although the tennis players tended to have more osteophytes at the TF joints and hip, but the runners had more PF joint disease. Within the control group, a small subgroup of 22 women who reported long-term vigorous weight-bearing exercise had risks of OA similar to those of the ex-athletes. Ex-athletes had similar rates of symptom reporting but higher pain thresholds than controls, as measured by calibrated dolorimeter. Conclusion. Weight-bearing sports activity in women is associated with a 2–3-fold increased risk of radiologic OA (particularly the presence of osteophytes) of the knees and hips. The risk was similar in ex–elite athletes and in a subgroup from the general population who reported long-term sports activity, suggesting that duration rather than frequency of training is important.
Article
Objective. To determine the relationship between different physical loading conditions and findings of knee osteoarthritis (OA). Methods. We selected 117 male former top-level athletes (age range 45–68 years) who had participated in sports activities with distinctly different loading conditions: 28 had been long-distance runners, 31 soccer players, 29 weight lifters, and 29 shooters. Histories of lifetime occupational and athletic knee loading, knee injuries, and knee symptoms were obtained, and subjects were examined clinically and radiographically for knee findings of OA. Results. The prevalence of tibiofemoral or patellofemoral OA based on radiographic examination was 3% in shooters, 29% in soccer players, 31% in weight lifters, and 14% in runners (P = 0.016 between groups). Soccer players had the highest prevalence of tibiofemoral OA (26%), and weight lifters had the highest prevalence of patellofemoral OA (28%). Subjects with radiographically documented knee OA had more symptoms, clinical findings, and functional limitations than did subjects without knee OA. By stepwise logistic regression analysis, the risk for having knee OA was increased in subjects with previous knee injuries (odds ratio [OR] 4.73), high body mass index at the age of 20 (OR 1.76/unit of increasing body mass index), previous participation in heavy work (OR 1.08/work-year), kneeling or squatting work (OR 1.10/work-year), and in subjects participating in soccer (OR 5.21). Conclusion. Soccer players and weight lifters are at increased risk of developing premature knee OA. The increased risk is explained in part by knee injuries in soccer players and by high body mass in weight lifters.
Article
Diabetes, hypertension, and ischemic heart disease are less frequent among physically active subjects. The aim of the present national population-based study was to compare the prevalence of these three diseases between former Finnish elite athletes and referents. The subjects consisted of surviving former male athletes who represented Finland between the years 1920 and 1965 at least once in international competitions and referents who at the age of 20 were classified as completely healthy at a medical examination, and who responded to a questionnaire in 1985 (athletes, n = 1,282; referents n = 777). In 1985, they completed a questionnaire with medical, life-style, and psychosocial items; at that time, the leisure physical activity was greater in previous athletes than in referents. The presence or absence of the three diseases was identified from the questionnaire or from at least one of three registers: Finnish hospital inpatient discharge register, reimbursable medication register, and disability pension register. When compared with referents, both endurance and mixed-sports athletes had lower age-adjusted odds ratios (ORs) for all studied diseases. Compared with referents, power-sports athletes had a higher risk for high body mass index (BMI) but a lower risk for ischemic heart disease. Subjects with high BMI had an increased risk for all three diseases. Smokers had a higher risk for diabetes and ischemic heart disease compared with those who were never smokers. After adjustments for age, BMI, smoking history, and occupational group, compared with referents, former endurance athletes had the lowest ORs for diabetes (OR 0.24; 95% confidence interval, 0.07 to 0.81) and ischemic heart disease (OR 0.33; 0.18 to 0.61).(ABSTRACT TRUNCATED AT 250 WORDS)
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The influence of excessive running load on the development of knee osteoarthritis (OA) was investigated in male Wistar rats. Running exercises were performed in a running wheel using intracranial self-stimulation to motivate Wistar rats to run daily distances of 500 m at 5 days/week. Hereby, ten rats ran a distance of 15 km within three weeks while a further ten rats run a total of 30 km within six weeks. Thirteen Wistar rats without running exercises served as controls. Complete knee joint sections of all rats were evaluated histologically using MANKINs grading system with categorization of the findings into non, mild moderate, and severe osteoarthritis. In addition, immunoreactivity of the chondrocytes to MMP-3 as an important cartilage degrading enzyme in OA was assessed by immunostaining with monoclonal MMP-3 IgG antibodies.
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Injuries to the hip and pelvis make up a small but significant proportion of painful conditions in runners. Most of these injuries are due to overuse and some, such as femoral neck stress fracture, may involve significant morbidity. Apophyseal injuries are becoming more prevalent and should be considered in the skeletally immature athlete. Stress fractures and soft-tissue injuries occur in all age-groups, often because of excessive mechanical stress without adequate recovery periods. A systematic approach to evaluation and treatment-combined with knowledge of indications for surgical referral, training principles, and shoe-wear patterns-allows the physician to individualize the athlete's rehabilitation and return to running, and to help the athlete prevent re-injury.
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Visual simple and choice reaction time (RT) tests were administered to 64 male and female volunteers 23 to 59 years of age. One half of the subjects were runners involved in rigorous training programs averaging 42 miles per week. The other half of the subjects were sedentary adults. Eighty simple and 100 choice reaction time trials were given with a variable foreperiod ranging from 400 to 1100 msec. Five catch trials were given in both simple and choice reaction time conditions. The results indicated that there was a gradual decline in RT performance as age increased. However, this trend was not evident in the trained group. Reaction time remained constant with age within the trained group. It was concluded that a high state of cardiorespiratory training may prevent cognitive decrements in performance with age.
Article
The influences of the strenuous running training program on the knee joint articular cartilage was studied in six female beagle dogs. At the age of 15 weeks, the dogs started running on a treadmill inclined 15 degrees uphill. Thereafter, the dogs were trained for 40 weeks, five times a week. For the final 15 weeks, the dogs ran 20 km/day. Six age-matched female beagles served as controls. The cartilage surfaces were intact after the running exercise. The training reduced the thickness of the uncalcified cartilage by 6% in the medial femoral condyle. The glycosaminoglycan concentration was reduced an average of 11% on the summits of the femoral condyles. The reduction was most pronounced (41%) in the superficial 50-micron cartilage zone. In other regions of the knee, such a decrease of glycosaminoglycans was not observed. A shift to strenuous running voided the increase in cartilage thickness and proteoglycan content previously observed after moderate running. Strenuous running induced marked depletion of proteoglycans from the superficial layer of the femoral condyles at sites subjected to highest impact loads.
Article
In order to evaluate the effect of long-term, long distance running on the incidence of degenerative joint disease in the lower extremities, we examined the hips, knees, and ankles of 30 long distance runners who had been serious competitive runners in the early 1950s (at the age of 20 to 30 years). Of three runners who were no longer active, one had stopped running in the late 1970s because of osteoarthrosis of both the lower and upper extremity joints. The remaining 27 runners (90%) were still active, having run 20 to 40 km/week (12 to 24 miles/week) for a median of 40 years. Subjective, objective, and roentgenographic data were compared with the data for 27 nonrunning controls matched as to age, weight, height, and occupation. No differences in joint alignment, range of motion, or complaints of pain were found between runners and nonrunners. Roentgenographic examinations for cartilage thickness, grade of degeneration, and osteophytosis were also without significant differences between the two groups. Thus, our observations suggest that a lifetime of long distance running at mileage levels comparable to those of recreational runners today is not associated with premature osteoarthrosis in the joints of the lower extremities.