Ultrasonography of chronic tendon injuries the groin PETER
KÄLEBO,*†‡
MD, PhD, JON KARLSSON,§ MD, PhD, LEIF AND LARS
SWARD,§
in
MD, PhD,
PETERSON,∥ MD,
PhD
From the
Departments of *Diagnostic Radiology and § Orthopaedic Surgery, East Hospital, University of Gothenburg, the †Biomaterials Group, Department of Handicap Research, University of Gothenburg, and the ∥ Gothenburg Medical Center, Gothenburg, Sweden
ABSTRACT
ing of muscle and tendon injuries and related lesions. 7, 9,10,17, 20, 21, 25, 26 Imaging of ruptures, tendinitis, bursitis, and postoperative changes has been possible with this mo-
Ultrasonography was used in the diagnosis of 36 patients with chronic groin pain localized to the tendons of the rectus abdominis, rectus femoris, adductor muscles, hamstring muscles, and the gluteal muscles. Abnormal findings, such as focal sonolucent areas and discontinuity of tendon fibers, that are indicative of nonhealed partial ruptures were found in 28 patients. These findings differed clearly from the asymptomatic contralateral side, which was used for comparison. The abnormalities were located in three different sites: at the tendon insertion, within the tendon, and at the tendomuscular junction. Ten patients were treated surgically and the findings at surgery correlated well with the ultrasonographic findings of partial tendon tears: 9 were true-positive and 1 was a true-negative. Ultrasonography appears to be a valuable method in the diagnosis of chronic groin pain.
dality,8,13,19
and the findings have been shown to correlate well with surgical findings. 15,16,18,28 However, experience with ultrasound examination of tendons and tendomuscular junctions in the groin, as well as muscular tears, is limited. 10,22 We have found no systematic evaluation of the value of ultrasonography in the detection of chronic tendon injuries in the groin. The aim of this study was to document the abnormalities in the proximal tendons and tendomuscular junctions of the rectus femoris, rectus abdominis, adductor muscles, hamstring muscles, and the gluteal muscles in patients with chronic groin pain caused by sports injuries, and to correlate the ultrasonographic and surgical findings.
PATIENTS AND METHODS 28 male and 8 female, aged 14 to 57 (mean, 27), underwent clinical and ultrasonographic examination for groin pain. The mean duration of symptoms was 1.5 years (range, 3 months to 4 years) and represented
Thirty-six patients,
years
Sports-related tendon injuries in the groin are frequent, sometimes resulting in long-lasting disability. Chronic localized pain in tendons may be caused by a nonhealed, underlying partial tendon rupture, resulting from overuse or strain injury.ll This disruption is frequently neglected because of the difficulties in clinical diagnosis and lack of knowledge about treatment.1,4,23-24, 27,29,30,32 Lack of adequate methods to visualize and locate the abnormalities affect one’s ability to diagnose these lesions. Despite our knowledge of the clinical features of these injuries, the pathologic and radiologic documentation is limited.&dquo;, 24,30,31 The recent introduction of high-resolution, real-time ultrasonography allows unique possibilities for direct imag-
mixture of sudden to gradual onset. All individuals complained of pain and weakness in the affected groin area a
during physical activity. Clinical examination The clinical examination included inspection, palpation, and estimations of the muscle function (strength and range of motion). Inspection in both contraction and relaxation was performed to register any defect or dysfunction in the muscles or tendons. Palpation was carried out to detect painful areas. Estimation of the muscle function for strength and range of movement was in comparison to the unaffected side.
+ Address correspondence and repnnt requests to Peter Kalebo, MD, PhD, Department of Radiology, East Hospital, S-416 85 Gothenburg, Sweden 634
635
Ultrasonography The examinations were carried out using a real-time scanner (128, Acuson, Mountain View, CA) equipped with a 7 MHz linear-array transducer. Avulsion fractures had been ruled out by plain radiography before ultrasound examination. The tendons were scanned at both longitudinal and transverse projections to identify the tendons and the muscles and to assess the extent and location of the lesion. The contralateral side and the other asymptomatic groin tendons were always examined for comparison. Moreover, compression of the actual area with the probe was used to locate the lesion. To avoid false hypoechoic tendon artifacts resulting from oblique projections,’ the beam was always centered perpendicular to the tendon fibers.
Surgery In 10 individuals, surgical treatment was performed after conservative management failed. Areas that were clinically suspected for a rupture and areas with abnormalities according to the ultrasound examination were exposed. Abnormal tissue was excised and healthy tissue was carefully sutured with an absorbable material.
RESULTS Clinical
findings
Thirty-three patients had unilateral pain: 13 at palpation over the proximal part of the hamstring muscles, 9 at palpation over the proximal part of the adductor muscle group, 5 over the proximal part of the rectus femoris muscle, 4 over the gluteal muscle tendons, and 2 over the distal part of the rectus abdominis muscle. Three patients had pain at palpation
over
2
or more
different
areas.
In all
cases
where
a
comparison between the two sides was possible there was a decrease in the strength and range of movement of the affected muscles. Normal
ultrasonographic findings
proximal tendons and tendomuscular junctions of the abdominis, rectus femoris, hamstring, adductor, and gluteal muscle groups all appeared to have a relatively short tendon, 2 to 4 cm in length. The longitudinally oriented collagen fibers of the tendons appeared as an echoic fibrillar pattern. There were no sharp tendomuscular junctions, rather a gradual transition of echogenic tendon fibers to the more low-echoic muscular bundles (Figs. 1A, 2A, 4A). The
rectus
Abnormal
findings
In 28 of the 36 patients, ultrasound examination showed abnormalities in the region of the painful areas. All of the abnormalities consisted of focal hypoechoic (i.e., low-reflective) areas and discontinuity of tendon fibers. Moreover, probe compression of these hypoechoic areas resulted in
Figure 1. Longitudinal sonographic image of a normal tendon of the proximal rectus femoris muscle (arrowheads). A, note the tendon, appearing as a high-echoic, fibrillar pattern of short length. B, partial tendon rupture, i.e., a low-echoic area with discontinuity of tendon fibers (arrowheads). 0, the tendon ongin. pain in the majority of the patients. These lesions measured from 5 to 30 mm in length. Hyperechoic lesions were not seen, except for small calcifications within the hypoechoic areas in two patients with signs of apophysitis (Fig. 5) There were no cases of a complete tendon tear. These focal sonolucent findings, suggestive of partial ruptures, were located in the proximal tendon (12 patients), in the tendomuscular junction (11patients), or in the tendon-
636
Figure 3. Longitudinal (A) and transverse (B) ultrasonograms of a low-echoic area with loss of tendon fibers (arrowheads) at the insertion of the hamstrings tendon indicating a partial tear. 0, the tendon origin. ultrasonographic findings. There were 4 patients with ruptures found in the adductor longus, 4 in the rectus femoris, Figure 2. A, longitudinal ultrasonographic view of a normal hamstrings tendon (arrowheads). B, a proximal partial tendon rupture (arrowheads) on the symptomatic side. 0, the tendon origin. bone junction (5 patients). Generally, injuries in the proximal rectus femoris or in the hamstring, adductor, or gluteal muscle groups were located within the tendon or in the tendomuscular junction in adults, whereas adolescents often showed lesions at the attachment, usually in the rectus abdominis, rectus femoris, and hamstrings and adductor muscle groups. The ultrasonographic in Figures 1 through 5.
findings are presented
and 1 in the rectus abdominis muscle. The abnormal tissue appeared light yellow with no tendon/muscle texture, and it was macroscopically judged as fibrous or devitalized/degenerated tissue resulting from a nonhealed partial rupture. In five cases, histopathology of excised material confirmed the findings of focal degeneration, disruption of collagen fibers, and neovascularization in the tissue. In one patient who had surgery in the adductor region, the ultrasound examination was normal. No pathologic area was found at surgery and a tenotomy was performed instead. Only one minor complication was registered, a superficial infection that healed with local treatment.
Surgery
Followup
In 9 of 10 surgically treated patients, there were positive findings of partial ruptures that correlated well with the
Thirty-two patients were interviewed 12 to 36 months (mean, 21) after the investigation or operation. We failed to
3>5,12 good anatomic depictions of the actual regions have been obtained. However, ultrasonography has advantages over
in
tennis Clin
Sports
Med 7
349-357,1988 2 Beltran J, Noto AM, Herman LJ, et al Tendons. High-field-strength, surface coil MR imaging Radiology 162. 735-740, 1987 3 De Smet AA, Fisher DR, Heiner JP, et al Magnetic resonance imaging of muscle tears Skeletal Radiol 19 283-286, 1990 4 Ekberg O, Persson NH, Abrahamsson PA, et al Longstanding groin pain in athletes A multidisciplinary approach Sports Med 6. 56-61, 1988 5. Fleckenstein JL, Weatherall PT, Parkey RW, et al Sports-related muscle injuries Evaluation with MR imaging. Radiology 172 793-798, 1989 6.
extent, the size of the injury. The ultrasonographic findings were
Balduini FC Abdominal and groin injuries
Fornage
BD The
hypoechoic
normal tendon A
pitfall
J Ultrasound Med
6 19-22, 1987 7
Fornage
BD Achilles tendon US examnation
Radiology
159 759-764,
1986 8
Fornage BD, Rifkin MD Ultrasound examination of tendons. Radiol Clin North Am 26 87-107, 1988 9 Fornage BD, Rifkin MD, Touche DH, et al Sonography of the patellar tendon Prelimmary observations AJR 143. 179-182, 1984 10. Fornage BD, Touche DH, Segal P, et al Ultrasonography in the evaluation of muscular trauma J Ultrasound Med 2 549-554, 1983 11 Garrett WE Jr Muscle strain injuries Clinical and basic aspects Med Sci Sports Exerc 22 436-443, 1990 12 Garrett WE Jr, Rich FR, Nikolaou PK, et al Computed tomography of hamstring muscle strains Med Sci Sports Exerc 21 506-514, 1989 13 Harcke HT, Grissom LE, Finkelstein MS Evaluation of the musculoskeletal system with sonography AJR 150 1253-1261, 1988 14 Hess H. Leistenschmerz-Atiologie, Differentialdiagnose und therapeutische Moglichkeiten Orthopade 9. 186-189, 1980 15. Kainberger FM, Engel A, Barton P, et al Injury of the Achilles tendon; Diagnosis with sonography. AJR 155 1031-1036, 1990 16. Kalebo P, Allenmark C, Peterson L, et al Diagnostic value of ultrasonography of partial ruptures of the Achilles tendon. Am J Sports Med 20 37817
381, 1992 Kalebo P, Goksor
L-Å, Sward L, et al Soft-tissue radiography, computed tomography, and ultrasonography of partial Achilles tendon ruptures. Acta
Radiol 31 565-570, 1990 18 Kalebo P, Sward L, Karlsson J, et al
19. 20. 21 22
23.
Ultrasonography in the detection of partial patellar ligament ruptures (jumper’s knee) Skeletal Radiol 20 285289, 1991 Kaplan PA, Anderson JC, Norris MA, et al; Ultrasonography of posttraumatic soft-tissue lesions Radiol Clin North Am 27. 973-982, 1989 Laine HR, Harjula ALJ, Peltokallio P. Ultrasonography as a differential diagnostic aid in achillodynia J Ultrasound Med 6 351-362, 1987 Laine HR, Harjula A, Peltokallio P Ultrasound in the evaluation of the knee and patellar regions J Ultrasound Med 6: 33-36, 1987 Laine HR, Harjula A, Peltokallio P Experience with real-time sonography in muscle injuries Scand J Sports Sci 7. 45-49, 1985 Lehman RC Thoracoabdominal musculoskeletal injuries in racquet sports Clin Sports Med 7 267-276, 1988
639 24 Martens MA, Hansen L, Mulier JC Adductor tendinitis and musculus rectus abdominis tendopathy Am J Sports Med 15 353-356, 1987 25 Mathieson JR, Connell DG, Cooperberg PL, et al Sonography of the Achilles tendon and adjacent bursae AJR 151 127-131, 1988 26 Mourad K, King J, Guggiana P Computed tomography and ultrasound imaging of jumper s knee - patellar tendinitis Clin Radiol 39 162-165, 1988 27 Mozes M, Papa MZ, Zweig A, et al Iliopsoas injury in soccer players Br J Sports Med 19 168-170, 1985
28 Myllymaki T, Bondestam S, Suramo I, et al Ultrasonography of jumper’s knee Acta Radiol 31 147-149, 1990 29 Overbeck W Die schmerzhafte Leiste bei Sportlern-eine chirurgische Indikation? Chirurg 60 756-759, 1989 30 Renstrom P, Peterson L Groin injuries in athletes Br J Sports Med 14
30-36, 1980 31
Schneider PG Leistenschmerz.
Operative Therapiemoglichkeiten
Ortho-
190-192, 1980 pade9 32 Zimmerman G Groin pain 1988
in
athletes Aust Fam
Physician
17 1046-1052,
KÄLEBO,*†‡
MD, PhD, JON KARLSSON,§ MD, PhD, LEIF AND LARS
SWARD,§
in
MD, PhD,
PETERSON,∥ MD,
PhD
From the
Departments of *Diagnostic Radiology and § Orthopaedic Surgery, East Hospital, University of Gothenburg, the †Biomaterials Group, Department of Handicap Research, University of Gothenburg, and the ∥ Gothenburg Medical Center, Gothenburg, Sweden
ABSTRACT
ing of muscle and tendon injuries and related lesions. 7, 9,10,17, 20, 21, 25, 26 Imaging of ruptures, tendinitis, bursitis, and postoperative changes has been possible with this mo-
Ultrasonography was used in the diagnosis of 36 patients with chronic groin pain localized to the tendons of the rectus abdominis, rectus femoris, adductor muscles, hamstring muscles, and the gluteal muscles. Abnormal findings, such as focal sonolucent areas and discontinuity of tendon fibers, that are indicative of nonhealed partial ruptures were found in 28 patients. These findings differed clearly from the asymptomatic contralateral side, which was used for comparison. The abnormalities were located in three different sites: at the tendon insertion, within the tendon, and at the tendomuscular junction. Ten patients were treated surgically and the findings at surgery correlated well with the ultrasonographic findings of partial tendon tears: 9 were true-positive and 1 was a true-negative. Ultrasonography appears to be a valuable method in the diagnosis of chronic groin pain.
dality,8,13,19
and the findings have been shown to correlate well with surgical findings. 15,16,18,28 However, experience with ultrasound examination of tendons and tendomuscular junctions in the groin, as well as muscular tears, is limited. 10,22 We have found no systematic evaluation of the value of ultrasonography in the detection of chronic tendon injuries in the groin. The aim of this study was to document the abnormalities in the proximal tendons and tendomuscular junctions of the rectus femoris, rectus abdominis, adductor muscles, hamstring muscles, and the gluteal muscles in patients with chronic groin pain caused by sports injuries, and to correlate the ultrasonographic and surgical findings.
PATIENTS AND METHODS 28 male and 8 female, aged 14 to 57 (mean, 27), underwent clinical and ultrasonographic examination for groin pain. The mean duration of symptoms was 1.5 years (range, 3 months to 4 years) and represented
Thirty-six patients,
years
Sports-related tendon injuries in the groin are frequent, sometimes resulting in long-lasting disability. Chronic localized pain in tendons may be caused by a nonhealed, underlying partial tendon rupture, resulting from overuse or strain injury.ll This disruption is frequently neglected because of the difficulties in clinical diagnosis and lack of knowledge about treatment.1,4,23-24, 27,29,30,32 Lack of adequate methods to visualize and locate the abnormalities affect one’s ability to diagnose these lesions. Despite our knowledge of the clinical features of these injuries, the pathologic and radiologic documentation is limited.&dquo;, 24,30,31 The recent introduction of high-resolution, real-time ultrasonography allows unique possibilities for direct imag-
mixture of sudden to gradual onset. All individuals complained of pain and weakness in the affected groin area a
during physical activity. Clinical examination The clinical examination included inspection, palpation, and estimations of the muscle function (strength and range of motion). Inspection in both contraction and relaxation was performed to register any defect or dysfunction in the muscles or tendons. Palpation was carried out to detect painful areas. Estimation of the muscle function for strength and range of movement was in comparison to the unaffected side.
+ Address correspondence and repnnt requests to Peter Kalebo, MD, PhD, Department of Radiology, East Hospital, S-416 85 Gothenburg, Sweden 634
635
Ultrasonography The examinations were carried out using a real-time scanner (128, Acuson, Mountain View, CA) equipped with a 7 MHz linear-array transducer. Avulsion fractures had been ruled out by plain radiography before ultrasound examination. The tendons were scanned at both longitudinal and transverse projections to identify the tendons and the muscles and to assess the extent and location of the lesion. The contralateral side and the other asymptomatic groin tendons were always examined for comparison. Moreover, compression of the actual area with the probe was used to locate the lesion. To avoid false hypoechoic tendon artifacts resulting from oblique projections,’ the beam was always centered perpendicular to the tendon fibers.
Surgery In 10 individuals, surgical treatment was performed after conservative management failed. Areas that were clinically suspected for a rupture and areas with abnormalities according to the ultrasound examination were exposed. Abnormal tissue was excised and healthy tissue was carefully sutured with an absorbable material.
RESULTS Clinical
findings
Thirty-three patients had unilateral pain: 13 at palpation over the proximal part of the hamstring muscles, 9 at palpation over the proximal part of the adductor muscle group, 5 over the proximal part of the rectus femoris muscle, 4 over the gluteal muscle tendons, and 2 over the distal part of the rectus abdominis muscle. Three patients had pain at palpation
over
2
or more
different
areas.
In all
cases
where
a
comparison between the two sides was possible there was a decrease in the strength and range of movement of the affected muscles. Normal
ultrasonographic findings
proximal tendons and tendomuscular junctions of the abdominis, rectus femoris, hamstring, adductor, and gluteal muscle groups all appeared to have a relatively short tendon, 2 to 4 cm in length. The longitudinally oriented collagen fibers of the tendons appeared as an echoic fibrillar pattern. There were no sharp tendomuscular junctions, rather a gradual transition of echogenic tendon fibers to the more low-echoic muscular bundles (Figs. 1A, 2A, 4A). The
rectus
Abnormal
findings
In 28 of the 36 patients, ultrasound examination showed abnormalities in the region of the painful areas. All of the abnormalities consisted of focal hypoechoic (i.e., low-reflective) areas and discontinuity of tendon fibers. Moreover, probe compression of these hypoechoic areas resulted in
Figure 1. Longitudinal sonographic image of a normal tendon of the proximal rectus femoris muscle (arrowheads). A, note the tendon, appearing as a high-echoic, fibrillar pattern of short length. B, partial tendon rupture, i.e., a low-echoic area with discontinuity of tendon fibers (arrowheads). 0, the tendon ongin. pain in the majority of the patients. These lesions measured from 5 to 30 mm in length. Hyperechoic lesions were not seen, except for small calcifications within the hypoechoic areas in two patients with signs of apophysitis (Fig. 5) There were no cases of a complete tendon tear. These focal sonolucent findings, suggestive of partial ruptures, were located in the proximal tendon (12 patients), in the tendomuscular junction (11patients), or in the tendon-
636
Figure 3. Longitudinal (A) and transverse (B) ultrasonograms of a low-echoic area with loss of tendon fibers (arrowheads) at the insertion of the hamstrings tendon indicating a partial tear. 0, the tendon origin. ultrasonographic findings. There were 4 patients with ruptures found in the adductor longus, 4 in the rectus femoris, Figure 2. A, longitudinal ultrasonographic view of a normal hamstrings tendon (arrowheads). B, a proximal partial tendon rupture (arrowheads) on the symptomatic side. 0, the tendon origin. bone junction (5 patients). Generally, injuries in the proximal rectus femoris or in the hamstring, adductor, or gluteal muscle groups were located within the tendon or in the tendomuscular junction in adults, whereas adolescents often showed lesions at the attachment, usually in the rectus abdominis, rectus femoris, and hamstrings and adductor muscle groups. The ultrasonographic in Figures 1 through 5.
findings are presented
and 1 in the rectus abdominis muscle. The abnormal tissue appeared light yellow with no tendon/muscle texture, and it was macroscopically judged as fibrous or devitalized/degenerated tissue resulting from a nonhealed partial rupture. In five cases, histopathology of excised material confirmed the findings of focal degeneration, disruption of collagen fibers, and neovascularization in the tissue. In one patient who had surgery in the adductor region, the ultrasound examination was normal. No pathologic area was found at surgery and a tenotomy was performed instead. Only one minor complication was registered, a superficial infection that healed with local treatment.
Surgery
Followup
In 9 of 10 surgically treated patients, there were positive findings of partial ruptures that correlated well with the
Thirty-two patients were interviewed 12 to 36 months (mean, 21) after the investigation or operation. We failed to
3>5,12 good anatomic depictions of the actual regions have been obtained. However, ultrasonography has advantages over
in
tennis Clin
Sports
Med 7
349-357,1988 2 Beltran J, Noto AM, Herman LJ, et al Tendons. High-field-strength, surface coil MR imaging Radiology 162. 735-740, 1987 3 De Smet AA, Fisher DR, Heiner JP, et al Magnetic resonance imaging of muscle tears Skeletal Radiol 19 283-286, 1990 4 Ekberg O, Persson NH, Abrahamsson PA, et al Longstanding groin pain in athletes A multidisciplinary approach Sports Med 6. 56-61, 1988 5. Fleckenstein JL, Weatherall PT, Parkey RW, et al Sports-related muscle injuries Evaluation with MR imaging. Radiology 172 793-798, 1989 6.
extent, the size of the injury. The ultrasonographic findings were
Balduini FC Abdominal and groin injuries
Fornage
BD The
hypoechoic
normal tendon A
pitfall
J Ultrasound Med
6 19-22, 1987 7
Fornage
BD Achilles tendon US examnation
Radiology
159 759-764,
1986 8
Fornage BD, Rifkin MD Ultrasound examination of tendons. Radiol Clin North Am 26 87-107, 1988 9 Fornage BD, Rifkin MD, Touche DH, et al Sonography of the patellar tendon Prelimmary observations AJR 143. 179-182, 1984 10. Fornage BD, Touche DH, Segal P, et al Ultrasonography in the evaluation of muscular trauma J Ultrasound Med 2 549-554, 1983 11 Garrett WE Jr Muscle strain injuries Clinical and basic aspects Med Sci Sports Exerc 22 436-443, 1990 12 Garrett WE Jr, Rich FR, Nikolaou PK, et al Computed tomography of hamstring muscle strains Med Sci Sports Exerc 21 506-514, 1989 13 Harcke HT, Grissom LE, Finkelstein MS Evaluation of the musculoskeletal system with sonography AJR 150 1253-1261, 1988 14 Hess H. Leistenschmerz-Atiologie, Differentialdiagnose und therapeutische Moglichkeiten Orthopade 9. 186-189, 1980 15. Kainberger FM, Engel A, Barton P, et al Injury of the Achilles tendon; Diagnosis with sonography. AJR 155 1031-1036, 1990 16. Kalebo P, Allenmark C, Peterson L, et al Diagnostic value of ultrasonography of partial ruptures of the Achilles tendon. Am J Sports Med 20 37817
381, 1992 Kalebo P, Goksor
L-Å, Sward L, et al Soft-tissue radiography, computed tomography, and ultrasonography of partial Achilles tendon ruptures. Acta
Radiol 31 565-570, 1990 18 Kalebo P, Sward L, Karlsson J, et al
19. 20. 21 22
23.
Ultrasonography in the detection of partial patellar ligament ruptures (jumper’s knee) Skeletal Radiol 20 285289, 1991 Kaplan PA, Anderson JC, Norris MA, et al; Ultrasonography of posttraumatic soft-tissue lesions Radiol Clin North Am 27. 973-982, 1989 Laine HR, Harjula ALJ, Peltokallio P. Ultrasonography as a differential diagnostic aid in achillodynia J Ultrasound Med 6 351-362, 1987 Laine HR, Harjula A, Peltokallio P Ultrasound in the evaluation of the knee and patellar regions J Ultrasound Med 6: 33-36, 1987 Laine HR, Harjula A, Peltokallio P Experience with real-time sonography in muscle injuries Scand J Sports Sci 7. 45-49, 1985 Lehman RC Thoracoabdominal musculoskeletal injuries in racquet sports Clin Sports Med 7 267-276, 1988
639 24 Martens MA, Hansen L, Mulier JC Adductor tendinitis and musculus rectus abdominis tendopathy Am J Sports Med 15 353-356, 1987 25 Mathieson JR, Connell DG, Cooperberg PL, et al Sonography of the Achilles tendon and adjacent bursae AJR 151 127-131, 1988 26 Mourad K, King J, Guggiana P Computed tomography and ultrasound imaging of jumper s knee - patellar tendinitis Clin Radiol 39 162-165, 1988 27 Mozes M, Papa MZ, Zweig A, et al Iliopsoas injury in soccer players Br J Sports Med 19 168-170, 1985
28 Myllymaki T, Bondestam S, Suramo I, et al Ultrasonography of jumper’s knee Acta Radiol 31 147-149, 1990 29 Overbeck W Die schmerzhafte Leiste bei Sportlern-eine chirurgische Indikation? Chirurg 60 756-759, 1989 30 Renstrom P, Peterson L Groin injuries in athletes Br J Sports Med 14
30-36, 1980 31
Schneider PG Leistenschmerz.
Operative Therapiemoglichkeiten
Ortho-
190-192, 1980 pade9 32 Zimmerman G Groin pain 1988
in
athletes Aust Fam
Physician
17 1046-1052,
