Botulinum Toxin as a Treatment for Functional Popliteal Artery Entrapment Syndrome MARIE-EVE ISNER-HOROBETI1’2, GUILLAUME MUFF1’2, JULIEN MASAT1’2, JEAN-LUC DAUSSIN4, STEPHANE P. DUFOUR2’3, and JEHAN LECOCQ2’5 University Institute o f Rehabilitation Clemenceau, Department o f Physical and Rehabilitation Medicine, Strasbourg University, Strasbourg, FRANCE; 2Federation de Medecine Translationnelle de Strasbourg (FMTS), EA 3072 “Mitochondrie, stress oxydant et protection musculaire,” Strasbourg, FRANCE; 3Faculty o f Sports Sciences, Strasbourg University, Strasbourg, FRANCE; 4Faculty o f Medicine, Department o f Radiology, Strasbourg University and University Hospital, Strasbourg, FRANCE; and 5Faculty o f Medicine, Institute o f Physiology, Strasbourg University and Strasbourg University Hospital, Strasbourg, FRANCE
CLINICAL SCIENCES
ABSTRACT ISNER-HOROBETI, M.-E., G. MUFF, J. MASAT, J.-L. DAUSSIN, S. P. DUFOUR, and J. LECOCQ. Botulinum Toxin as a Treatment for Functional Popliteal Artery Entrapment Syndrome. Med. Sci. Sports Exerc., Vol. 47, No. 6, pp. 1124-1127, 2015. Purpose: Func tional popliteal artery entrapment syndrome is responsible for exercise-induced muscle leg pain. This syndrome is caused, in m ost o f the cases, by the excessive size o f the gastrocnemius muscles. Currently, its treatment is based only on surgery with variable results.
Methods: We report the case o f a young professional soldier in a combat unit with bilateral functional popliteal artery entrapment syndrome that was confirmed by dynamic arteriography, magnetic resonance angiography, and ultrasonography and did not improve after bilateral popliteal arteriolysis without resection o f the gastrocnemius medial head. Treatment by injecting botulinum toxin in the proximal part o f the gastrocnemius muscles was proposed and carried out. Results: Regular follow-up (from 1 month to 3 yr after botulinum toxin treatment) showed the disappearance o f exercise-induced pain and the improvement o f the patient’s physical and sports performance. Results o f follow-up ultrasonography during dynamic maneuvers at 2.5 months and 2 yr after botulinum toxin injection were normal. Neither adverse effects nor m otor deficit o f the gastrocnemius m uscles was reported. Conclusions: This case report suggests that botulinum toxin treatment could be an alternative to surgery for patients with functional popliteal artery entrapment syndrome. Botulinum toxin could reduce functional compression and, consequently, exercise-induced pain by decreasing the volume o f the gastroc nemius muscle. Key Words: LEG PAIN, SPORT, TRAINING, ATHLETES, GASTROCNEMIUS MUSCLE, POPLITEAL ARTERY
opliteal artery entrapment syndrome is rare and can cause exercise-induced leg pain in athletes. There are five anatomic types of popliteal artery entrapment syndrome (four involve only arterial compression and one involves both arterial and venous compressions). These forms are caused by anatomic compression (i.e., due to a supernu merary muscle, aponeurotic abnormality [13] or an abnormal course of the artery [4,26]) and can be successfully treated with surgical elimination of the anatomic trap (12). Con versely, in the functional popliteal artery entrapment syn drome (FPAES) (27), no anatomic compression is detected, and entrapment is thought to be caused by hypertrophy of the gastrocnemius muscle during physical exercise in athletic patients (1,32). Its therapeutic management is challenging
P
Address for correspondence: Marie-Eve lsner-Horobeti, M.D., Ph.D., Institut Universitaire de Readaptation Clemenceau-Strasbourg, 45 boulevard Clemenceau, F-67000 Strasbourg, France; E-mail: [email protected]. Submitted for publication July 2014. Accepted for publication October 2014. 0195-9131/15/4706-1124/0 M EDICINE & SCIENCE IN SPORTS & EXERCISE® Copyright © 2014 by the American College o f Sports Medicine DOI: 10.1249/M SS.0000000000000538
because it is difficult to reduce the volume of a very devel oped or a short and thick muscle without functional conse quences. Some authors have proposed to perform popliteal arteriolysis to release the artery from the surrounding tissue and reduce the vascular compression. However, at the mo ment, a lack of standardized outcomes does not allow to reach conclusions on the effectiveness of this approach (5,8,21). Physical therapy, such as massage and stretching, may be proposed to reduce muscle contraction or retraction, but it cannot, in any case, modify the muscle morphotype or vol ume. Therefore, it is important to find new treatments. Re cently, Botulinum toxin A (BoNT-A) has been proposed as an alternative approach to reduce the volume and/or tonus of gastrocnemius muscles in patients with FPAES (11). In deed, BoNT-A has been used successfully for the treatment of unaesthetic masseter (2,16) and calf hypertrophy (14,20), postsciatica muscle hypertrophy (6,29), and muscle patholo gies, such as exertional compartment syndrome (15,18,19). We report the following case of a patient who was mistakenly initially diagnosed with chronic exertional com partment syndrome and underwent unsuccessful compart ment release with subsequent diagnosis of bilateral FPAES and unsuccessful arteriolysis. The patient was then successfully treated by injection of BoNT-A in the gastrocnemius muscles.
1124
CASE REPORT
BOTULINUM TOXIN FOR LEG PAIN IN AN ATHLETE
M e d ic in e & S c ie n c e in S p o rts & Exercise®
1125
CLINICAL SCIENCES
A 22-yr-old French anny corporal, with no previous med ical conditions, was required to participate in regular 4 h d _1 of vigorous and intense sports activity, such as running, swimming, and cycling. Since 2000, he had been suffering from exercise-induced pain localized on the posterior aspect of both lower limbs. Such pain appeared exclusively during strenuous repetitive exercise (walking or running) and was accompanied by diffuse (plantar and dorsal) foot paresthesia that disappeared after stopping the physical exercise. Exer tional compartment syndrome was erroneously suspected based on the slightly increased compartment pressure in the anterolateral compartments, which were normal in the poste rior compartments of the legs. Bilateral aponeurotomy of the anterolateral compartments of the legs was carried out in 2003, but no improvement was noted and the patient’s sports and professional activities remained very limited. In 2006, bilateral FPAES was diagnosed because dynamic arteriogra phy and magnetic resonance angiography ruled out the pres ence of anatomic abnormalities of the arterial course or of the gastrocnemius muscle insertions. Bilateral compression of the popliteal arteries was identified during isometric plantarflexion against maximal resistance. This was associated with diffuse pain in the posterior compartment of both legs (9). Popliteal arteriolysis without resection of the medial head of the gastrocnemius muscle in the right leg was carried out in February 2006 and then in the left leg in April 2006. The improvement was of short duration (only a few months) as the patient continued to experience exercise-induced pain that limited his military and sports activities. In December 2010, the military doctor referred the patient to our outpa tient clinic because of persistence of pain. Indeed, he had to be exempted from the annual military physical competi tions at the end of 2010. During the clinical interview, he complained about exercise-induced pain, unchanged from 2000, despite the different treatments. Pain was localized in the posterior aspect of both legs. It appeared after 15-20 min of vigorous exercise (walking or running) and was accom panied by diffuse (plantar and dorsal) foot paresthesia, forcing the patient to stop the physical activity. The pain disap peared within a few minutes after the end of exercise and passive recovery. This patient (weight = 77 kg, height = 1.62 m) had a brachymorphic body shape with a very devel oped musculature, particularly the calves, and a very high distal myotendinous junction of the gastrocnemius. Dynamic maneuvers (maximal passive dorsiflexion and maximal active plantarflexion) led to the disappearance of the distal pulses and the appearance of diffuse pain in the posterior leg com partments. No evidence of vertebral or neurological abnor mality was detected. The laboratory workup, which included muscle enzymes, thyroid function, iron metabolism status, and calcium and phosphate levels, as well as Lyme disease serology, was normal. X-ray and bone scintigraphy did not find any abnormality. The stress test (running on a treadmill with a 4° slope at 12.5 km h ') triggered pain in the posterior
aspect of both legs and had to be stopped after 23 min. The intramuscular pressure of the right and left deep posterior leg compartments was 17 mm Hg, 1 min after stopping the test. The pressure of the right and left superficial posterior com partments was 7 mm Hg, 5 min after the stress test. Doppler sonography of the legs with the patient at rest in dorsal decubitus showed that the vascular axes from the aorta down to the distal vessels of the lower limbs were normally patent and without any anatomic abnormality. In the same position, the dynamic maneuvers of the active plantarflexion and pas sive dorsiflexion of the foot with the knee in hyperextension blocked the flow of the tibial posterior artery on both sides. During the analysis in standing position on tiptoes, the flow of the popliteal artery and sural arteries disappeared on the right side concomitantly with the appearance of pain; on the left side, the flow persisted only in the sural arteries. The ankle brachial pressure index (the systolic pressure at the ankle divided by the systolic pressure at the arm) was nonnal at rest (1.26 on the right and 1.22 on the left). After the stress test that triggered the pain, these values decreased to 0.73 on the right and to 0.78 on the left. Overall, this assessment suggested an FPAES, particularly on the right side, related to the patient’s morphotype and shape of the gastrocnemius muscle. A new magnetic resonance angiography was not per formed because the surgical interventions of 2006 did elimi nate the causative anatomic pathology. As surgery in 2006 did not provide long-lasting im provement, a treatment by injection of BoNT-A was pro posed to the patient. This treatment was approved by the local University Hospital ethics committee. After being in formed about BoNT-A indications, contraindications, and adverse effects, the patient gave his written informed con sent for this treatment and to the publication of informa tion concerning his case. In January 2011, BoNT-A (Dysport; diluted in 2.5 ntL of saline solution to obtain 500 Speywood Units [SU]) was injected in the proximal third of the medial and lateral gastrocnemius muscles of both legs (200 SU per injection point; total dose per leg = 400 SU) using a needle electrode (0.46 mm in diameter and 50 mm in length) (Bioject; Alpine Biomed Aps, Denmark) after EMG identification of the muscles (Cefar Rehab, France). Ten sessions of stretching of the triceps surae were prescribed after BoNT-A injection. One month after the treatment, the patient no longer com plained about pain during fast and prolonged walking and did not report any adverse effect. Muscle testing did not highlight any motor deficit of the triceps surae or any other anomaly. At the 2.5-month follow-up, Doppler sonography did not detect any flow modification during the dynamic maneuvers. After 4 months, results were considered very satisfactory by the patient who went back to his sports activ ities and did not report any pain, particularly while running, which he practices up to 2 h d_1, as well as during cycling (1 h d _1) and swimming (2 h-d-1). Results of physical ex amination were normal, and the patient did not report any adverse effect. Results were similar at the 8-month follow-up. After 1 yr, ultrasonography was still normal, and no sign of
CLINICAL SCIENCES
right or left FPAES was detected. Meanwhile, he partici pated in the annual military competition with a clear im provement of his performance. At the 18-month follow-up, his sports and military performance levels were still excel lent. Results of dynamic Doppler sonography were also nor mal. The ankle brachial pressure index, after treadmill stress test in the same conditions as before the treatment, was 1.06 on the right and 1 on the left, confirming the normalization relative to the pretreatment test. At the 2-yr follow-up, the level of his sports and professional activities was unchanged. Indeed, he could perform physical tests for 4 h without the appearance of leg pain. Ultrasonography did not detect any sign of right and left FPAES. Three years after the interven tion, the patient was still performing sports and professional activities without pain or discomfort.
DISCUSSION FPAES was described for the first time by Rignault et al. (27) in 1985. In contrast to the anatomic entrapped popliteal artery syndrome in which arterial and musculotendinous abnormalities within the popliteal fossa compress vessels and nerves even at rest, no anatomic abnormality is found in FPAES. According to Rignault, this syndrome is more frequent in young athletic individuals with well-developed muscles. Several authors (7,28,30,32) have hypothesized that, during physical exertion, a muscle of big volume (natural or ac quired) might compress the neurovascular bundle in the popliteal fossa. Flowever, FPAES has been also described in nonathletic and nontrained individuals (9), suggesting the existence of an anatomic predisposition. Indeed, in 16 in dividuals with FPAES, Pillai et al. (22) have reported the existence of an embryonic variant of the medial head of the gastrocnemius that occupies the medial part of the pop liteal fossa, thus compressing the popliteal artery. The clin ical signs not only are linked to the compression of the popliteal artery but also can be related to the compression of the posterior tibial nerve. The current treatment (popliteal arteriolysis associated or not with the release of the soleus muscle from its tibial attachments, resection of its fascial band and resection of the plantaris muscle [32]) is proposed only in the presence of altered locomotor function. Postop erative results are good in the short term (1 yr) (8) but have not been thoroughly evaluated and may not persist in the long term (17). Here, we report the case of a young man with bilateral FPAES who underwent unsuccessful com partment release and was then treated with intramuscular injection of BoNT-A. He has a muscular anatomy (high myotendinous junction of the triceps surae muscles), possi bly worsened by calf hypertrophy because of his vigorous sports activity (active army man). Bilateral popliteal arterio lysis improved the situation only for few months. The reap pearance of exercise-induced pain could have been caused by the presence of postoperative fibrosis. However, the ab sence of anomalies, particularly at rest, at the follow-up
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Doppler sonography investigations did not substantiate this hypothesis. On the basis of these elements, a therapeutic alternative was needed, and injection of BoNT-A in the gastrocne mius muscles was proposed to the patient. The amount of BoNT-A to be injected (i.e., the smallest effective and non paralyzing dose) was chosen based on literature data and the authors’ experience in the field of spasticity (3,23), mus culoskeletal disorders (24,29,34), and exertional compart ment syndrome (15). After EMG localization of the muscles, BoNT-A was injected in the proximal and medial parts of each gastrocnemius (both internal and external head) because they were thought to be responsible for the compression at the level of the popliteal fossa. In our case report, BoNT-A was successfully used to treat a patient with bilateral FPAES. Three years after BoNT-A injection, he can perform vigorous exercise, and the last Doppler sonography at the 1-yr follow-up did not show any anomaly. The patient did not report any adverse effect and particularly did not have any motor deficit at the 1-month follow-up. It is impossible to say that the patient’s recovery is certainly due to the BoNT-A injection because its phar macological effect normally lasts between 3 and 6 months (25). However, because other possible diagnoses were elim inated and all other treatments were unsuccessful, the hy pothesis that the BoNT-A treatment relieved the functional arterial compression and improved exercise tolerance is suf ficiently plausible to support future investigations. The role of sex, physical deconditioning, and type/amount of physical activity performed after the treatment could not be evaluated based on a single case report. The mechanism of action of BoNT-A in this context remains to be identified, but the most probable explanation involves the reduction of muscle tone and induction of at rophy (10,31,33) linked to BoNT-A-induced chemodenervation. Its choice for this indication was based on its use in unaesthetic and/or painful calf hypertrophies (14,20) and in muscle pathology, such as exertional compartment syndrome (15). In conclusion, we report the case of a patient with bilat eral FPAES to whom treatment by intramuscular injection of BoNT-A in the gastrocnemius muscles was proposed after unsuccessful surgical intervention. The disappearance of exercise-induced pain and the improvement in physical performance are maintained in the short and medium term. These encouraging results need to be confirmed in further studies to explore the full potential of BoNT-A in FPAES as an alternative to surgical intervention.
The authors would like to thank Professor Nabil Chakfe, Head of Department of Vascular Surgery and Kidney Transplanta tion, University Hospitals of Strasbourg for critical reading of the article. No funding was received for this work. The authors declare no conflict of interest. The results of the present study do not constitute endorsement by the American College of Sports Medicine.
http://www.acsm-msse.org
REFERENCES
BOTULINUM TOXIN FOR LEG PAIN IN AN ATHLETE
18. Lecocq J, Isner-Horobeti ME. Treatment of exertional compart ment syndrome leg with botulinum toxin A: a first open pilot study. J Rehabil Med. 2008;(47 Suppl):l 11-2. 19. Lecocq J, Isner-Horobeti ME, Dupeyron A, Helmlinger JL, Vautravers P. Exertional compartment syndrome (in French). Ann Readapt Med Phys. 2004;47(6):334-45. 20. Lee HJ, Lee DW, Park YH, Cha MK, Kim HS, Ha SJ. Botulinum toxin a for aesthetic contouring of enlarged medial gastrocnemius muscle. Dermatol Surg. 2004;30(6):867—71 discussion 71. 21. Lejay A, Ohana M, Lee JT, et al. Popliteal artery entrapment syndrome. J Cardiovasc Surg. 2014;55(2 Suppl 1):225—37. 22. Pillai J, Levien LJ, Haagensen M, Candy G, Cluver MD, Veller MG. Assessment o f the medial head of the gastrocnemius muscle in functional compression of the popliteal artery. J Vase Surg. 2008' 48(5): 1189-96. 23. Pittock SJ, Moore AP, Hardiman O, et al. A double-blind ran domised placebo-controlled evaluation o f three doses o f botulinum toxin type A (Dysport) in the treatment o f spastic equinovarus deformity after stroke. Cerebrovasc Dis. 2003;15(4):289-300. 24. Placzek R, Drescher W, Deuretzbacher G, Hempfmg A, Meiss AL. Treatment of chronic radial epicondylitis with botulinum toxin A. A double-blind, placebo-controlled, randomized muiticenter study. J Bone Joint Surg [Am], 2007;89(2):255-60. 25. Poulain B. Botulinum neurotoxin (in French). Rev Neurol (Paris). 2010; 166(1):7—20. 26. Rich NM, Collins GJ Jr, McDonald PT, Kozloff L, Clagett GP, Collins JT. Popliteal vascular entrapment. Its increasing interest. Arch Surg. 1979;114(12): 1377-84. 27. Rignault DP, Pailler JL, Lunel F. The “functional” popliteal en trapment syndrome. Int Angiol. 1985;4(3):341-3. 28. Rizzo RJ, Flinn WR, Yao JS, McCarthy WJ, Vogelzang RL, Pearce WH. Computed tomography for evaluation of arterial dis ease in the popliteal fossa. J Vase Surg. 1990; 11(1): 112—9. 29. Soares A, Andriolo RB, Atallah AN, da Silva EM. Botulinum toxin for myofascial pain syndromes in adults. Cochrane Database Syst Rev. 2012;4:CD007533. 30. Stuart TP. Note on a variation in the course of the popliteal artery. JA n a t Physiol. 1879;13(Pt 2):162. 31. To EW, Ahuja AT, Ho WS, et al. A prospective study o f the effect of botulinum toxin A on masseteric muscle hypertrophy with ul trasonographic and electromyographic measurement. Br J Plast Surg. 2001;54(3): 197-200. 32. Tumipseed WD, Pozniak M. Popliteal entrapment as a result of neurovascular compression by the soleus and plantaris muscles. J Vase Surg. 1992; 15(2):285—93 discussion 93—4. 33. von Lindem JJ, Niederhagen B, Appel T, Berge S, Reich RH. Type A botulinum toxin for the treatment of hypertrophy o f the masseter and temporal muscles: an alternative treatment. Plast Reconstr Surg. 2001; 107(2):327-32. 34. Waseem Z, Boulias C, Gordon A, Ismail F, Sheean G, Furlan AD. Botulinum toxin injections for low-back pain and sciatica. Cochrane Database Syst Rev. 2011;(1):CD008257.
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1. Akkersdijk WL, de Ruyter JW, Lapham R, Mali W, Eikelboom BC. Colour duplex ultrasonographic imaging and provocation of popli teal artery compression. Eur J Vase Endovasc Surg. 1995;10(3):342-5. 2. Ascher B, Talarico S, Cassuto D, et al. International consensus recommendations on the aesthetic usage of botulinum toxin type A (Speywood Unit)—Part II: Wrinkles on the middle and lower face, neck and chest. J Eur Acad Dermatol Venereol. 2010;24( 1l):1285-95. 3. Burbaud P, Wiart L, Dubos JL, et al. A randomised, double blind, placebo controlled trial of botulinum toxin in the treatment of spastic foot in hemiparetic patients. J Neurol Neurosurg Psychia try. 1996;61(3):265-9. 4. Carter AE, Eban R. A Case of bilateral developmental abnormality of the popliteal arteries and gastrocnemius muscles. Br J Surg. 1964;51:518-22. 5. Causey MW, Singh N, Miller S, Quan R, Curry T, Andersen C. Intraoperative duplex and functional popliteal entrapment syn drome: strategy for effective treatment. Ann Vase Surg. 2010; 24(4):556—61. 6. Costa J, Graca P, Evangelista T, de Carvalho M. Pain and calf hy pertrophy associated with spontaneous repetitive discharges treated with botulinum toxin. Clin Neurophysiol. 2005;116( 12):2847—52. 7. Darling RC, Buckley CJ, Abbott WM, Raines JK. Intermittent claudication in young athletes: popliteal artery entrapment syn drome. J Trauma. 1974; 14(7):543—52. 8. Deshpande A, Denton M. Functional popliteal entrapment syn drome. A u s tN Z J S u r g . 1998;68(9):660-3. 9. Erdoes LS, Devine JJ, Bernhard VM, Baker MR, Berman SS, Hunter GC. Popliteal vascular compression in a normal population. J Vase Surg. 1994;20(6):978-86. 10. Finn S, Ryan P, Sleeman D. The medical management o f masseteric hypertrophy with botulinum toxin. J I r Dent Assoc. 2000;46(3):84-6. 11. Gandor F, Tisch S, Grabs AJ, Delaney AJ, Bester L, Darveniza P. Botulinum toxin A in functional popliteal entrapment syndrome: a new approach to a difficult diagnosis. J Neural Transm. 2014; 121(10): 1297-301. 12. Goh BK, Tay KH, Tan SG. Diagnosis and surgical management of popliteal artery entrapment syndrome. ANZ J Surg. 2005;75(10): 869-73. 13. Haimovici H, Sprayregen S, Johnson F. Popliteal artery entrap ment by fibrous band. Surgery. I972;72(5):789-92. 14. Han KH, Joo YH, Moon SE, Kim KH. Botulinum toxin A treatment for contouring of the lower leg. J Dermatolog Treat. 2006;17(4):250-4. 15. Isner-Horobeti ME, Dufour SP, Blaes C, Lecocq J. Intramuscular pressure before and after botulinum toxin in chronic exertional compartment syndrome of the leg: a preliminary study. Am J Sports Med. 2013;41(11):2558—66. 16. Kim NH, Park RH, Park JB. Botulinum toxin type A for the treatment of hypertrophy of the masseter muscle. Plast Reconstr Surg. 2010; 125(6): 1693-705. 17. Lane R, Nguyen T, Cuzzilla M, Oomens D, Mohabbat W, Hazelton S. Functional popliteal entrapment syndrome in the sportsperson. Eur J Vase Endovasc Surg. 2012;43( 1):81—7.
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CLINICAL SCIENCES
ABSTRACT ISNER-HOROBETI, M.-E., G. MUFF, J. MASAT, J.-L. DAUSSIN, S. P. DUFOUR, and J. LECOCQ. Botulinum Toxin as a Treatment for Functional Popliteal Artery Entrapment Syndrome. Med. Sci. Sports Exerc., Vol. 47, No. 6, pp. 1124-1127, 2015. Purpose: Func tional popliteal artery entrapment syndrome is responsible for exercise-induced muscle leg pain. This syndrome is caused, in m ost o f the cases, by the excessive size o f the gastrocnemius muscles. Currently, its treatment is based only on surgery with variable results.
Methods: We report the case o f a young professional soldier in a combat unit with bilateral functional popliteal artery entrapment syndrome that was confirmed by dynamic arteriography, magnetic resonance angiography, and ultrasonography and did not improve after bilateral popliteal arteriolysis without resection o f the gastrocnemius medial head. Treatment by injecting botulinum toxin in the proximal part o f the gastrocnemius muscles was proposed and carried out. Results: Regular follow-up (from 1 month to 3 yr after botulinum toxin treatment) showed the disappearance o f exercise-induced pain and the improvement o f the patient’s physical and sports performance. Results o f follow-up ultrasonography during dynamic maneuvers at 2.5 months and 2 yr after botulinum toxin injection were normal. Neither adverse effects nor m otor deficit o f the gastrocnemius m uscles was reported. Conclusions: This case report suggests that botulinum toxin treatment could be an alternative to surgery for patients with functional popliteal artery entrapment syndrome. Botulinum toxin could reduce functional compression and, consequently, exercise-induced pain by decreasing the volume o f the gastroc nemius muscle. Key Words: LEG PAIN, SPORT, TRAINING, ATHLETES, GASTROCNEMIUS MUSCLE, POPLITEAL ARTERY
opliteal artery entrapment syndrome is rare and can cause exercise-induced leg pain in athletes. There are five anatomic types of popliteal artery entrapment syndrome (four involve only arterial compression and one involves both arterial and venous compressions). These forms are caused by anatomic compression (i.e., due to a supernu merary muscle, aponeurotic abnormality [13] or an abnormal course of the artery [4,26]) and can be successfully treated with surgical elimination of the anatomic trap (12). Con versely, in the functional popliteal artery entrapment syn drome (FPAES) (27), no anatomic compression is detected, and entrapment is thought to be caused by hypertrophy of the gastrocnemius muscle during physical exercise in athletic patients (1,32). Its therapeutic management is challenging
P
Address for correspondence: Marie-Eve lsner-Horobeti, M.D., Ph.D., Institut Universitaire de Readaptation Clemenceau-Strasbourg, 45 boulevard Clemenceau, F-67000 Strasbourg, France; E-mail: [email protected]. Submitted for publication July 2014. Accepted for publication October 2014. 0195-9131/15/4706-1124/0 M EDICINE & SCIENCE IN SPORTS & EXERCISE® Copyright © 2014 by the American College o f Sports Medicine DOI: 10.1249/M SS.0000000000000538
because it is difficult to reduce the volume of a very devel oped or a short and thick muscle without functional conse quences. Some authors have proposed to perform popliteal arteriolysis to release the artery from the surrounding tissue and reduce the vascular compression. However, at the mo ment, a lack of standardized outcomes does not allow to reach conclusions on the effectiveness of this approach (5,8,21). Physical therapy, such as massage and stretching, may be proposed to reduce muscle contraction or retraction, but it cannot, in any case, modify the muscle morphotype or vol ume. Therefore, it is important to find new treatments. Re cently, Botulinum toxin A (BoNT-A) has been proposed as an alternative approach to reduce the volume and/or tonus of gastrocnemius muscles in patients with FPAES (11). In deed, BoNT-A has been used successfully for the treatment of unaesthetic masseter (2,16) and calf hypertrophy (14,20), postsciatica muscle hypertrophy (6,29), and muscle patholo gies, such as exertional compartment syndrome (15,18,19). We report the following case of a patient who was mistakenly initially diagnosed with chronic exertional com partment syndrome and underwent unsuccessful compart ment release with subsequent diagnosis of bilateral FPAES and unsuccessful arteriolysis. The patient was then successfully treated by injection of BoNT-A in the gastrocnemius muscles.
1124
CASE REPORT
BOTULINUM TOXIN FOR LEG PAIN IN AN ATHLETE
M e d ic in e & S c ie n c e in S p o rts & Exercise®
1125
CLINICAL SCIENCES
A 22-yr-old French anny corporal, with no previous med ical conditions, was required to participate in regular 4 h d _1 of vigorous and intense sports activity, such as running, swimming, and cycling. Since 2000, he had been suffering from exercise-induced pain localized on the posterior aspect of both lower limbs. Such pain appeared exclusively during strenuous repetitive exercise (walking or running) and was accompanied by diffuse (plantar and dorsal) foot paresthesia that disappeared after stopping the physical exercise. Exer tional compartment syndrome was erroneously suspected based on the slightly increased compartment pressure in the anterolateral compartments, which were normal in the poste rior compartments of the legs. Bilateral aponeurotomy of the anterolateral compartments of the legs was carried out in 2003, but no improvement was noted and the patient’s sports and professional activities remained very limited. In 2006, bilateral FPAES was diagnosed because dynamic arteriogra phy and magnetic resonance angiography ruled out the pres ence of anatomic abnormalities of the arterial course or of the gastrocnemius muscle insertions. Bilateral compression of the popliteal arteries was identified during isometric plantarflexion against maximal resistance. This was associated with diffuse pain in the posterior compartment of both legs (9). Popliteal arteriolysis without resection of the medial head of the gastrocnemius muscle in the right leg was carried out in February 2006 and then in the left leg in April 2006. The improvement was of short duration (only a few months) as the patient continued to experience exercise-induced pain that limited his military and sports activities. In December 2010, the military doctor referred the patient to our outpa tient clinic because of persistence of pain. Indeed, he had to be exempted from the annual military physical competi tions at the end of 2010. During the clinical interview, he complained about exercise-induced pain, unchanged from 2000, despite the different treatments. Pain was localized in the posterior aspect of both legs. It appeared after 15-20 min of vigorous exercise (walking or running) and was accom panied by diffuse (plantar and dorsal) foot paresthesia, forcing the patient to stop the physical activity. The pain disap peared within a few minutes after the end of exercise and passive recovery. This patient (weight = 77 kg, height = 1.62 m) had a brachymorphic body shape with a very devel oped musculature, particularly the calves, and a very high distal myotendinous junction of the gastrocnemius. Dynamic maneuvers (maximal passive dorsiflexion and maximal active plantarflexion) led to the disappearance of the distal pulses and the appearance of diffuse pain in the posterior leg com partments. No evidence of vertebral or neurological abnor mality was detected. The laboratory workup, which included muscle enzymes, thyroid function, iron metabolism status, and calcium and phosphate levels, as well as Lyme disease serology, was normal. X-ray and bone scintigraphy did not find any abnormality. The stress test (running on a treadmill with a 4° slope at 12.5 km h ') triggered pain in the posterior
aspect of both legs and had to be stopped after 23 min. The intramuscular pressure of the right and left deep posterior leg compartments was 17 mm Hg, 1 min after stopping the test. The pressure of the right and left superficial posterior com partments was 7 mm Hg, 5 min after the stress test. Doppler sonography of the legs with the patient at rest in dorsal decubitus showed that the vascular axes from the aorta down to the distal vessels of the lower limbs were normally patent and without any anatomic abnormality. In the same position, the dynamic maneuvers of the active plantarflexion and pas sive dorsiflexion of the foot with the knee in hyperextension blocked the flow of the tibial posterior artery on both sides. During the analysis in standing position on tiptoes, the flow of the popliteal artery and sural arteries disappeared on the right side concomitantly with the appearance of pain; on the left side, the flow persisted only in the sural arteries. The ankle brachial pressure index (the systolic pressure at the ankle divided by the systolic pressure at the arm) was nonnal at rest (1.26 on the right and 1.22 on the left). After the stress test that triggered the pain, these values decreased to 0.73 on the right and to 0.78 on the left. Overall, this assessment suggested an FPAES, particularly on the right side, related to the patient’s morphotype and shape of the gastrocnemius muscle. A new magnetic resonance angiography was not per formed because the surgical interventions of 2006 did elimi nate the causative anatomic pathology. As surgery in 2006 did not provide long-lasting im provement, a treatment by injection of BoNT-A was pro posed to the patient. This treatment was approved by the local University Hospital ethics committee. After being in formed about BoNT-A indications, contraindications, and adverse effects, the patient gave his written informed con sent for this treatment and to the publication of informa tion concerning his case. In January 2011, BoNT-A (Dysport; diluted in 2.5 ntL of saline solution to obtain 500 Speywood Units [SU]) was injected in the proximal third of the medial and lateral gastrocnemius muscles of both legs (200 SU per injection point; total dose per leg = 400 SU) using a needle electrode (0.46 mm in diameter and 50 mm in length) (Bioject; Alpine Biomed Aps, Denmark) after EMG identification of the muscles (Cefar Rehab, France). Ten sessions of stretching of the triceps surae were prescribed after BoNT-A injection. One month after the treatment, the patient no longer com plained about pain during fast and prolonged walking and did not report any adverse effect. Muscle testing did not highlight any motor deficit of the triceps surae or any other anomaly. At the 2.5-month follow-up, Doppler sonography did not detect any flow modification during the dynamic maneuvers. After 4 months, results were considered very satisfactory by the patient who went back to his sports activ ities and did not report any pain, particularly while running, which he practices up to 2 h d_1, as well as during cycling (1 h d _1) and swimming (2 h-d-1). Results of physical ex amination were normal, and the patient did not report any adverse effect. Results were similar at the 8-month follow-up. After 1 yr, ultrasonography was still normal, and no sign of
CLINICAL SCIENCES
right or left FPAES was detected. Meanwhile, he partici pated in the annual military competition with a clear im provement of his performance. At the 18-month follow-up, his sports and military performance levels were still excel lent. Results of dynamic Doppler sonography were also nor mal. The ankle brachial pressure index, after treadmill stress test in the same conditions as before the treatment, was 1.06 on the right and 1 on the left, confirming the normalization relative to the pretreatment test. At the 2-yr follow-up, the level of his sports and professional activities was unchanged. Indeed, he could perform physical tests for 4 h without the appearance of leg pain. Ultrasonography did not detect any sign of right and left FPAES. Three years after the interven tion, the patient was still performing sports and professional activities without pain or discomfort.
DISCUSSION FPAES was described for the first time by Rignault et al. (27) in 1985. In contrast to the anatomic entrapped popliteal artery syndrome in which arterial and musculotendinous abnormalities within the popliteal fossa compress vessels and nerves even at rest, no anatomic abnormality is found in FPAES. According to Rignault, this syndrome is more frequent in young athletic individuals with well-developed muscles. Several authors (7,28,30,32) have hypothesized that, during physical exertion, a muscle of big volume (natural or ac quired) might compress the neurovascular bundle in the popliteal fossa. Flowever, FPAES has been also described in nonathletic and nontrained individuals (9), suggesting the existence of an anatomic predisposition. Indeed, in 16 in dividuals with FPAES, Pillai et al. (22) have reported the existence of an embryonic variant of the medial head of the gastrocnemius that occupies the medial part of the pop liteal fossa, thus compressing the popliteal artery. The clin ical signs not only are linked to the compression of the popliteal artery but also can be related to the compression of the posterior tibial nerve. The current treatment (popliteal arteriolysis associated or not with the release of the soleus muscle from its tibial attachments, resection of its fascial band and resection of the plantaris muscle [32]) is proposed only in the presence of altered locomotor function. Postop erative results are good in the short term (1 yr) (8) but have not been thoroughly evaluated and may not persist in the long term (17). Here, we report the case of a young man with bilateral FPAES who underwent unsuccessful com partment release and was then treated with intramuscular injection of BoNT-A. He has a muscular anatomy (high myotendinous junction of the triceps surae muscles), possi bly worsened by calf hypertrophy because of his vigorous sports activity (active army man). Bilateral popliteal arterio lysis improved the situation only for few months. The reap pearance of exercise-induced pain could have been caused by the presence of postoperative fibrosis. However, the ab sence of anomalies, particularly at rest, at the follow-up
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Doppler sonography investigations did not substantiate this hypothesis. On the basis of these elements, a therapeutic alternative was needed, and injection of BoNT-A in the gastrocne mius muscles was proposed to the patient. The amount of BoNT-A to be injected (i.e., the smallest effective and non paralyzing dose) was chosen based on literature data and the authors’ experience in the field of spasticity (3,23), mus culoskeletal disorders (24,29,34), and exertional compart ment syndrome (15). After EMG localization of the muscles, BoNT-A was injected in the proximal and medial parts of each gastrocnemius (both internal and external head) because they were thought to be responsible for the compression at the level of the popliteal fossa. In our case report, BoNT-A was successfully used to treat a patient with bilateral FPAES. Three years after BoNT-A injection, he can perform vigorous exercise, and the last Doppler sonography at the 1-yr follow-up did not show any anomaly. The patient did not report any adverse effect and particularly did not have any motor deficit at the 1-month follow-up. It is impossible to say that the patient’s recovery is certainly due to the BoNT-A injection because its phar macological effect normally lasts between 3 and 6 months (25). However, because other possible diagnoses were elim inated and all other treatments were unsuccessful, the hy pothesis that the BoNT-A treatment relieved the functional arterial compression and improved exercise tolerance is suf ficiently plausible to support future investigations. The role of sex, physical deconditioning, and type/amount of physical activity performed after the treatment could not be evaluated based on a single case report. The mechanism of action of BoNT-A in this context remains to be identified, but the most probable explanation involves the reduction of muscle tone and induction of at rophy (10,31,33) linked to BoNT-A-induced chemodenervation. Its choice for this indication was based on its use in unaesthetic and/or painful calf hypertrophies (14,20) and in muscle pathology, such as exertional compartment syndrome (15). In conclusion, we report the case of a patient with bilat eral FPAES to whom treatment by intramuscular injection of BoNT-A in the gastrocnemius muscles was proposed after unsuccessful surgical intervention. The disappearance of exercise-induced pain and the improvement in physical performance are maintained in the short and medium term. These encouraging results need to be confirmed in further studies to explore the full potential of BoNT-A in FPAES as an alternative to surgical intervention.
The authors would like to thank Professor Nabil Chakfe, Head of Department of Vascular Surgery and Kidney Transplanta tion, University Hospitals of Strasbourg for critical reading of the article. No funding was received for this work. The authors declare no conflict of interest. The results of the present study do not constitute endorsement by the American College of Sports Medicine.
http://www.acsm-msse.org
REFERENCES
BOTULINUM TOXIN FOR LEG PAIN IN AN ATHLETE
18. Lecocq J, Isner-Horobeti ME. Treatment of exertional compart ment syndrome leg with botulinum toxin A: a first open pilot study. J Rehabil Med. 2008;(47 Suppl):l 11-2. 19. Lecocq J, Isner-Horobeti ME, Dupeyron A, Helmlinger JL, Vautravers P. Exertional compartment syndrome (in French). Ann Readapt Med Phys. 2004;47(6):334-45. 20. Lee HJ, Lee DW, Park YH, Cha MK, Kim HS, Ha SJ. Botulinum toxin a for aesthetic contouring of enlarged medial gastrocnemius muscle. Dermatol Surg. 2004;30(6):867—71 discussion 71. 21. Lejay A, Ohana M, Lee JT, et al. Popliteal artery entrapment syndrome. J Cardiovasc Surg. 2014;55(2 Suppl 1):225—37. 22. Pillai J, Levien LJ, Haagensen M, Candy G, Cluver MD, Veller MG. Assessment o f the medial head of the gastrocnemius muscle in functional compression of the popliteal artery. J Vase Surg. 2008' 48(5): 1189-96. 23. Pittock SJ, Moore AP, Hardiman O, et al. A double-blind ran domised placebo-controlled evaluation o f three doses o f botulinum toxin type A (Dysport) in the treatment o f spastic equinovarus deformity after stroke. Cerebrovasc Dis. 2003;15(4):289-300. 24. Placzek R, Drescher W, Deuretzbacher G, Hempfmg A, Meiss AL. Treatment of chronic radial epicondylitis with botulinum toxin A. A double-blind, placebo-controlled, randomized muiticenter study. J Bone Joint Surg [Am], 2007;89(2):255-60. 25. Poulain B. Botulinum neurotoxin (in French). Rev Neurol (Paris). 2010; 166(1):7—20. 26. Rich NM, Collins GJ Jr, McDonald PT, Kozloff L, Clagett GP, Collins JT. Popliteal vascular entrapment. Its increasing interest. Arch Surg. 1979;114(12): 1377-84. 27. Rignault DP, Pailler JL, Lunel F. The “functional” popliteal en trapment syndrome. Int Angiol. 1985;4(3):341-3. 28. Rizzo RJ, Flinn WR, Yao JS, McCarthy WJ, Vogelzang RL, Pearce WH. Computed tomography for evaluation of arterial dis ease in the popliteal fossa. J Vase Surg. 1990; 11(1): 112—9. 29. Soares A, Andriolo RB, Atallah AN, da Silva EM. Botulinum toxin for myofascial pain syndromes in adults. Cochrane Database Syst Rev. 2012;4:CD007533. 30. Stuart TP. Note on a variation in the course of the popliteal artery. JA n a t Physiol. 1879;13(Pt 2):162. 31. To EW, Ahuja AT, Ho WS, et al. A prospective study o f the effect of botulinum toxin A on masseteric muscle hypertrophy with ul trasonographic and electromyographic measurement. Br J Plast Surg. 2001;54(3): 197-200. 32. Tumipseed WD, Pozniak M. Popliteal entrapment as a result of neurovascular compression by the soleus and plantaris muscles. J Vase Surg. 1992; 15(2):285—93 discussion 93—4. 33. von Lindem JJ, Niederhagen B, Appel T, Berge S, Reich RH. Type A botulinum toxin for the treatment of hypertrophy o f the masseter and temporal muscles: an alternative treatment. Plast Reconstr Surg. 2001; 107(2):327-32. 34. Waseem Z, Boulias C, Gordon A, Ismail F, Sheean G, Furlan AD. Botulinum toxin injections for low-back pain and sciatica. Cochrane Database Syst Rev. 2011;(1):CD008257.
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1. Akkersdijk WL, de Ruyter JW, Lapham R, Mali W, Eikelboom BC. Colour duplex ultrasonographic imaging and provocation of popli teal artery compression. Eur J Vase Endovasc Surg. 1995;10(3):342-5. 2. Ascher B, Talarico S, Cassuto D, et al. International consensus recommendations on the aesthetic usage of botulinum toxin type A (Speywood Unit)—Part II: Wrinkles on the middle and lower face, neck and chest. J Eur Acad Dermatol Venereol. 2010;24( 1l):1285-95. 3. Burbaud P, Wiart L, Dubos JL, et al. A randomised, double blind, placebo controlled trial of botulinum toxin in the treatment of spastic foot in hemiparetic patients. J Neurol Neurosurg Psychia try. 1996;61(3):265-9. 4. Carter AE, Eban R. A Case of bilateral developmental abnormality of the popliteal arteries and gastrocnemius muscles. Br J Surg. 1964;51:518-22. 5. Causey MW, Singh N, Miller S, Quan R, Curry T, Andersen C. Intraoperative duplex and functional popliteal entrapment syn drome: strategy for effective treatment. Ann Vase Surg. 2010; 24(4):556—61. 6. Costa J, Graca P, Evangelista T, de Carvalho M. Pain and calf hy pertrophy associated with spontaneous repetitive discharges treated with botulinum toxin. Clin Neurophysiol. 2005;116( 12):2847—52. 7. Darling RC, Buckley CJ, Abbott WM, Raines JK. Intermittent claudication in young athletes: popliteal artery entrapment syn drome. J Trauma. 1974; 14(7):543—52. 8. Deshpande A, Denton M. Functional popliteal entrapment syn drome. A u s tN Z J S u r g . 1998;68(9):660-3. 9. Erdoes LS, Devine JJ, Bernhard VM, Baker MR, Berman SS, Hunter GC. Popliteal vascular compression in a normal population. J Vase Surg. 1994;20(6):978-86. 10. Finn S, Ryan P, Sleeman D. The medical management o f masseteric hypertrophy with botulinum toxin. J I r Dent Assoc. 2000;46(3):84-6. 11. Gandor F, Tisch S, Grabs AJ, Delaney AJ, Bester L, Darveniza P. Botulinum toxin A in functional popliteal entrapment syndrome: a new approach to a difficult diagnosis. J Neural Transm. 2014; 121(10): 1297-301. 12. Goh BK, Tay KH, Tan SG. Diagnosis and surgical management of popliteal artery entrapment syndrome. ANZ J Surg. 2005;75(10): 869-73. 13. Haimovici H, Sprayregen S, Johnson F. Popliteal artery entrap ment by fibrous band. Surgery. I972;72(5):789-92. 14. Han KH, Joo YH, Moon SE, Kim KH. Botulinum toxin A treatment for contouring of the lower leg. J Dermatolog Treat. 2006;17(4):250-4. 15. Isner-Horobeti ME, Dufour SP, Blaes C, Lecocq J. Intramuscular pressure before and after botulinum toxin in chronic exertional compartment syndrome of the leg: a preliminary study. Am J Sports Med. 2013;41(11):2558—66. 16. Kim NH, Park RH, Park JB. Botulinum toxin type A for the treatment of hypertrophy of the masseter muscle. Plast Reconstr Surg. 2010; 125(6): 1693-705. 17. Lane R, Nguyen T, Cuzzilla M, Oomens D, Mohabbat W, Hazelton S. Functional popliteal entrapment syndrome in the sportsperson. Eur J Vase Endovasc Surg. 2012;43( 1):81—7.
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