AJR 2002; 178:973-977
© American Roentgen Ray Society
Femoral Head Osteochondral Lesions in Painful Hips of Athletes
MR Imaging Findings
Carolyn J. Weaver1,
Nancy M. Major,
William E. Garrett and
James E. Urbaniak
1
All authors: Department of Radiology, Duke University Medical Center, P. O.
Box 3808, Durham, NC 27710.
Received July 30, 2001;
accepted after revision September 25, 2001.
Presented at the annual meeting of the American Roentgen Ray Society,
Seattle, April—May 2001.
Address correspondence to C. J. Weaver.
Abstract
OBJECTIVE. This study describes the MR imaging findings of focal
osteochondral lesions found in the hips of 11 athletes with persistent pain
and normal findings on radiographs.
CONCLUSION. Osteochondral lesions of the femoral head are seen on MR
imaging as focal, medial areas of high T2-weighted and low T1-weighted signals
and should be considered as a possible cause of persistent hip or groin pain
in young, high-level athletes because the institution of appropriate treatment
may help to prevent late degenerative sequelae.
Introduction
Hip pain is a common presenting complaint of athletes. The onset of pain
may coincide temporally with a traumatic injury. These patients generally have
normal findings on radiographs at presentation. Those with persistent symptoms
often require further diagnostic imaging with MR imaging. Frequent
abnormalities found on MR imaging include labral tear or injury, stress
fracture, and avascular necrosis
[1]. We describe the clinical
and radiographic features of 11 athletes found to have femoral head lesions
similar in MR imaging appearance to osteochondral lesions in other locations,
such as the knee and ankle.
Materials and Methods
After the identification of an index case, we conducted a retrospective
search of our institution's hip MR imaging database for the preceding 18
months. We excluded patients with findings of classic avascular necrosis,
stress or insufficiency fracture, transient osteoporosis, evidence of
osteomyelitis, labral abnormality, and metastasis. Three examinations revealed
a small, focal area of decreased signal on T1-weighted and increased signal on
T2-weighted sequences in the anterior—superior portion of one femoral
head, similar to the abnormality identified in the index case. Subsequently,
an additional seven patients were prospectively identified, either at the time
of imaging at our institution or at the time of referral from outside
institutions, bringing the total number of patients to 11.
Conventional radiographs of the hip were obtained in all patients and were
uniformly found to show normal findings. MR protocol parameters varied, but
all included axial and coronal imaging with T1-weighted images (TR/TE, 600/13)
and fat-suppressed fast spin-echo T2-weighted images (3500/65), or (fast)
short tau inversion recovery images (4000/35; inversion time, 150 msec). The
conventional radiographs and MR images were reviewed by two musculoskeletal
radiologists and one orthopedic surgeon.
Three patients underwent follow-up examinations with MR imaging using the
same protocol between 2 months and 4 years after the initial detection of the
lesion; the others are being followed up clinically and have not undergone
further imaging.
Results
The patient population consisted of nine males and two females, ranging
from 15 to 41 years old, with an average age of 25 years. All of the patients
presented to their referring clinicians with complaints of persistent groin
pain. The duration of pain varied from patient to patient, ranging from 1 week
to 6 months at initial presentation. All patients were avid athletes, either
recreationally or at the collegiate or professional level. Three patients
played soccer; four, basketball; and one, ice hockey. One patient was an avid
water-skier; one, a competitive snow skier; and one, a competitive
power-lifter. Neither of the female patients were, or had recently been,
pregnant at the time of the onset of symptoms or at the time of their MR
examinations. Four of the 11 patients recalled a discrete traumatic event
preceding the onset of chronic hip pain.
The conventional radiographs revealed normal findings, as determined by the
musculoskeletal radiologists and the orthopedic surgeon. The MR images were
reviewed in consensus, and the findings were believed to be abnormal. In all
11 patients, the MR examination showed a focal area of decreased signal on
T1-weighted images and increased signal on T2-weighted images in the
anterior—superior portion of one femoral head, an appearance consistent
with bone marrow edema or contusion. The area of signal abnormality was small
in all cases, involving 10-25% of the femoral head, and was anteromedially
located (Fig.
1A,1B,1C,1D,1E,1F,1G).
In no case did the area of signal abnormality extend across the midline, nor
was any evidence of femoral head collapse present. Two patients had obvious
irregularity of the overlying articular cartilage in association with bone
marrow edema (Figs.
2A,2B
and
3A,3B).
No other signal abnormalities were seen in the bones or soft tissues of the
hips or pelvis. Specifically, no signal abnormalities suggestive of labral
abnormalities were present.
View larger version (102K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 1A. —26-year-old male soccer player at time of presentation with
6-month history of left hip pain (A—C) and at 2-month follow-up
(D—G). Coronal T1-weighted image (TR/TE, 600/13) shows
triangular-shaped area of decreased signal in 10-11 o'clock position
(arrow).
|
|
View larger version (100K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 1B. —26-year-old male soccer player at time of presentation with
6-month history of left hip pain (A—C) and at 2-month follow-up
(D—G). Coronal T2-weighted image with fat suppression
(TR/TEeff, 3500/65) shows corresponding area of increased signal
(arrow). Overlying cartilage is not seen well on this image.
|
|
View larger version (145K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 1C. —26-year-old male soccer player at time of presentation with
6-month history of left hip pain (A—C) and at 2-month follow-up
(D—G). Axial T1-weighted image (TR/TE, 600/13) shows medial
location of this injury, as evidenced by decreased signal in marrow
(arrow).
|
|
View larger version (121K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 1D. —26-year-old male soccer player at time of presentation with
6-month history of left hip pain (A—C) and at 2-month follow-up
(D—G). Coronal T1-weighted image (600/13) obtained at follow-up
shows irregular contour in medial aspect of femoral head in location of
previously seen triangular-shaped signal abnormality (arrow).
|
|
View larger version (107K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 1E. —26-year-old male soccer player at time of presentation with
6-month history of left hip pain (A—C) and at 2-month follow-up
(D—G). Corresponding coronal T2-weighted fat-suppressed image
(TR/TEeff, 3500/65) shows increased signal adjacent to region of
curvilinear decreased signal in subarticular medial aspect of femoral head
(arrow). Overlying cartilage may be thin in this location. Amount of
edema has decreased in comparison with prior examination (B), but
lesion is more organized.
|
|
View larger version (158K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 1F. —26-year-old male soccer player at time of presentation with
6-month history of left hip pain (A—C) and at 2-month follow-up
(D—G). Axial T1-weighted image (TR/TE, 600/13) shows decrease in
bone marrow edema in comparison with prior study (C)
(arrow).
|
|
View larger version (150K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 1G. —26-year-old male soccer player at time of presentation with
6-month history of left hip pain (A—C) and at 2-month follow-up
(D—G). Axial T2-weighted image with fat suppression
(TR/TEeff, 3500/65) shows decreased edema with focal area of high
signal (arrow).
|
|
View larger version (167K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 2A. —28-year-old male skier with 3-month history of hip pain.
Coronal T1-weighted image (TR/TE, 600/13) shows decreased signal in
subchondral bone at medial aspect of femoral head (arrow).
|
|
View larger version (118K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 2B. —28-year-old male skier with 3-month history of hip pain.
Corresponding coronal (fast) short tau inversion recovery image (4000/35;
inversion time, 150 msec) reveals increased signal in subchondral bone
(thick arrow), with visible cartilage loss shown by joint fluid
filling location of cartilage defect (thin arrow).
|
|
View larger version (70K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 3A. —21-year-old male soccer player with acute hip pain. Coronal
T2-weighted fat-suppressed image (TR/TEeff, 3500/65) shows area of
increased signal consistent with bone marrow edema in medial aspect of femoral
head (arrow).
|
|
View larger version (127K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 3B. —21-year-old male soccer player with acute hip pain.
Corresponding axial T2-weighted fat-suppressed image (3500/65) shows
irregularity along articular surface compatible with small osteochondral
lesion (arrow). Bone marrow edema is evident.
|
|
Three patients underwent arthroscopy at the time of diagnosis. All were
found to have cartilaginous defects in the anterior—superior femoral
head, confirming the diagnosis of osteochondral lesions
(Fig. 4). Three patients
underwent at least one follow-up MR examination between 2 and 8 months after
the initial examination. In two of the three repeated examinations, the area
of bone marrow edema had decreased in size in the interval. In the third, no
change occurred in the size or appearance of the lesion over 4 years (Fig.
1A,1B,1C,1D,1E,1F,1G).
View larger version (137K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 4. —25-year-old male soccer player with 1-month history of hip
pain. Image taken at time of arthroscopy shows large, irregular defect in
femoral head articular cartilage (arrows). This defect is located
over anteromedial aspect of femoral head.
|
|
Discussion
Osteochondral lesions have been reported in the talus and knee and have a
characteristic appearance on MR imaging
[2]. We have recognized the
appearance of such lesions in the hip and report on their MR imaging
appearance and occurrence in elite athletes.
Osteochondral lesions of the talus and femoral condyles are thought to
occur as a result of torsional impaction that causes microfractures of the
subchondral bone and deformation of the overlying hyaline cartilage
[3]. With enough impaction
force, cartilage is deformed to the extent that it cannot return to its
original shape on removal of pressure. Cartilage is known to have limited
regenerative capacity, likely due to its avascularity, and when damaged, it
undergoes chondrolysis, with the release of various enzymes and damage to the
collagen fiber network. It is this process that is postulated to lead to the
long-term degenerative sequelae sometimes seen in the knees or ankles of
patients with previous osteochondral injury
[4]. To prevent degenerative
joint disease, prompt treatment of osteochondral lesions of the knee or talus
is recommended
[5,6].
Arthroscopy, with removal of fragments and cartilage repair, is indicated in
patients with gross cartilaginous disruption. For small disruptions or
softening of the articular cartilage, it is recommended that the patient be
removed from sports with weightbearing as tolerated for 6-12 weeks
[7]. Despite treatment, many
osteochondral lesions of the knee or ankle lead to degenerative sequelae and
early osteoarthritis.
The MR imaging findings of the 11 patients in our series have the
characteristic appearance of osteochondral lesions that are typically
characterized by irregularity of the surface cartilage with abnormal bone
marrow signal in the subchondral bone, often with an associated joint
effusion. The medial location and focality of bone marrow edema in our series
of patients are in marked contrast to the typical location of classic
avascular necrosis, which can have a similar imaging appearance but usually
occurs in a larger area, between the 10 o'clock and 2 o'clock positions
[8]. Additionally, stability or
a decrease in size of the lesion on follow-up MR examinations in several
patients supports the diagnosis of osteochondral lesion because avascular
necrosis tends to progress rather than regress or resolve spontaneously
[9]. Further, the patient
population in which these lesions were identified is unique in terms of its
youth and avid participation in sports; these are not the type of individuals
predisposed to develop classic avascular necrosis or transient osteoporosis of
the hip. Idiopathic transient osteoporosis of the hip has been described in
middle-aged men and pregnant or recently pregnant women without a history of
trauma. The imaging characteristics of our patients are not compatible with
those of transient osteoporosis of the hip, which would involve more of the
femoral head. The history of high-level participation by all 11 patients in
sports that place torsional and impaction forces on the hips is consistent
with the diagnosis of osteochondral lesion. Finally, arthroscopic evaluation
performed on three patients actually revealed the cartilaginous defect in
every case.
Most of the patients in our series were teenagers or young adults, and all
participated in sports at a high level. Several played soccer, a sport known
to predispose individuals to early degenerative changes of the hip. A study of
286 former elite European soccer players by Lindberg et al.
[10] showed that coxarthrosis
was three times more common in retired soccer players than in age-matched
controls (mean age, 55 years). Other groups have found increased rates of
degenerative disease in the hips of former avid athletes and have postulated
that repeated compression of cartilage and shock forces to joints may be
responsible [11,
12].
We believe that the lesions seen in the hips of the athletes in our series
may be the type of acute—subacute injuries that predispose such
individuals to early degenerative changes of the hips. The mechanism of injury
leading to osteochondral injury in the hip is as yet uncertain; however, we
propose two possible theories. The first theory implicates transient
subluxation with resultant shearing of cartilage and underlying marrow edema.
Subluxation could result from the large rotational component of forces placed
on the hip while passing or kicking the ball. Such a mechanism would also be
expected to result in MR evidence of damage to the joint capsule and
associated soft-tissue injuries such as hematoma or edema in muscles or fat.
Although these findings were not present in the patients in our series,
delayed imaging could have resulted in missing the findings of injury from
such a mechanism. The other postulated mechanism for occurrence of
osteochondral lesions in the hip is impaction force, such as the force in
sudden stops or landing from jumps. This mechanism would be expected to lead
to marrow changes on both sides of the joint, known as "kissing
contusions." Also, evidence of soft-tissue changes would not necessarily
be expected from such a mechanism because all the abnormal forces would be
transmitted directly to the joint itself. No consensus has yet been reached as
the true culprit mechanism for osteochondral lesions in the hip.
Many classification schemes have been proposed for the characterization of
osteochondral injuries of the ankle and knee on the basis of findings on MR
imaging or arthroscopy, with the thought that the long-term outcomes of the
various types of lesions may differ
[5,
6,
13,
14]. These schemes are
generally based on the amount of cartilaginous disruption (irregularity, flap,
or free fragment) and the degree of abnormality of the adjacent subchondral
bone (depression, frank indentation, or fracture). An MR classification scheme
for osteochondral lesions of the femoral heads has not yet been developed. The
development of a classification scheme would require a compilation of a large
series of patients with MR imaging abnormalities. Unfortunately, our study is
limited by a small number of patients and a lack of follow-up imaging or
arthroscopy in several cases. Our findings, however, suggest that a population
worthy of further examination would be avid athletes participating in a sport,
such as soccer, which has been shown to predispose participants to the
development of early degenerative changes of the hip.
Our overall understanding of radiographically occult osteochondral lesions
has been greatly advanced over the past several years, as the use of MR
imaging in patients with normal findings on radiographs has become more
wide-spread and as improved sequences have allowed better determination of the
condition of the articular cartilage
[13,14,15].
Although osteochondral lesion is not a new diagnosis, our recognition of
femoral head osteochondral lesions on MR imaging is likely reflective of the
fact that MR imaging is now performed more frequently in patients with a
symptomatic hip and normal radiographic findings. Also, whereas arthroscopy
remains the gold standard for evaluation of cartilaginous injury, MR imaging
is extremely helpful because of its ability to detect associated lesions in
the subchondral bone and in the evaluation of joints in which arthroscopy is
technically more difficult, such as the ankle or hip. Given the current
widespread use of MR imaging for the evaluation of patients with knee or ankle
pain, the diagnosis of osteochondral injuries of the talus or femoral condyles
has become commonplace; however, the diagnosis by MR imaging of such lesions
in the femoral heads has not, to our knowledge, been previously described. We
believe that the MR imaging findings of the 11 patients in our series
represent osteochondral lesions similar to those previously described in the
talus and femoral condyles. Further, we believe that the lesions seen in the
patients in our series may be at least partial contributors to the early onset
of hip degenerative change previously described in elite athletes.
References
-
Edwards DJ, Lomas D, Villar RH. Diagnosis of the painful hip by
magnetic resonance imaging and arthroscopy. J Bone Joint Surg
Br 1995;77:374
-376
-
Bohndorf, K. Imaging of acute injuries of the articular surfaces
(chondral, osteochondral and subchondral fractures). Skeletal
Radiology 1999;28:545
-560[Medline]
-
Berndt AL, Harty M. Transchondral fractures (osteochondritis
dissecans) of the talus. J Bone Joint Surg Am
1959;41:988
-1020[Abstract/Free Full Text]
-
Blum GM, Tirman PFJ, Crues JV III, Deutsch AL. Osseous and
cartilaginous trauma. In: Mink JH, Crues JV III, Deutsch AL, eds.
MRI of the knee, 2nd ed. New York: Raven Press,
1993
-
Mayer G, Seidlein H. Chondral and osteochondral fractures of the
knee joint: treatment and result. Arch Orthop Trauma
Surg 1988;107:154
-157
-
Pritsch M, Horoskovsky H, Farine I. Arthroscopic treatment of
osteochondral lesions of the talus. J Bone Joint Surg
Am 1986;68:862
-865[Abstract/Free Full Text]
-
Ly PN, Fallat LM. Trans-chondral fractures of the talus: a review
of 64 surgical cases. J Foot Ankle Surg
1993;32:352
-374[Medline]
-
Beltran J, Herman L, Burk J. Femoral head avascular necrosis: MR
imaging with clinical-pathological-radionuclide correlations.
Radiology
1988;166:215
-220[Abstract/Free Full Text]
-
Kopecky KK, Braunstein EM, Brandt KD, et al. Apparent avascular
necrosis of the hip: appearance and spontaneous resolution of MR findings in
renal allograft recipients. Radiology
1991;179:523
-527[Abstract/Free Full Text]
-
Lindberg H, Roos H, Gardsell P. Prevalence of coxarthrosis in
former soccer players. Acta Orthop Scand
1993;64:165
-167[Medline]
-
Marti B, Knobloch M, Tschopp A, Jucker A, Howard H. Is excessive
running predictive of degenerative hip disease? controlled study of former
elite athletes. BMJ
1989;299:91
-93
-
Vingard E, Alfredsson L, Goldie I, Hogstedt C. Sports and
osteoarthritis of the hip: an epidemiologic study. Am J Sports
Med 1993;21:195
-200[Abstract/Free Full Text]
-
Mink JH, Deutsch AL. Occult cartilage and bone injuries of the
knee: detection, classification, and assessment with MR imaging.
Radiology
1989;170:823
-829[Abstract/Free Full Text]
-
Vellet AD, Marks PH, Fowler PJ, Monro TG. Occult post-traumatic
osteochodral lesions of the knee: prevalence, classification, and short-term
sequelae evaluated with MR imaging. Radiology
1991;178:271
-276[Abstract/Free Full Text]
-
DeSmet AA, Fisher DR, Burnstein MI, Graf BK, Lange RH. Value of MR
imaging in staging osteochondral lesions of the talus (osteochondritis
dissecans): result in 14 patients. AJR
1990;154:555
-558[Abstract/Free Full Text]
CiteULike 
Complore 
Connotea 
Del.icio.us 
Digg 
Reddit 
Technorati What's this?
Top
Abstract
Introduction
