Popliteal vascular compression in a normal population

Canalis cruropopliteus - the overlooked canal of Wenzel Gruber

It is widely known that the popliteal fossa and the lower leg are connected by a canal, containing the neuro-vascular bundle to the posterior leg region, containing the tibial nerve and the posterior tibial artery and veins. The existence of this canal has not been duly recognized in literature, even though it has been named by Wenzel Gruber in 1871, and its contents, walls, entrance, and exits have been extensively described by him in 1878. In the present paper, we would like to pay a homage to the work of this prominent anatomist, which retains its significance for contemporary surgical practice. The cruropopliteal canal, canalis cruropopliteus, as named by him, and having been assigned a multitude of terms in practice, deserves to regain its eponymous name - Gruber's canal. The history, and the anatomy with its clinical implications are discussed herein. We hereby recommend that the original name of this canal be included in anatomical textbooks and specialized literature.

Perivascular mechanical environment: A narrative review of the role of externally applied mechanical force in the pathogenesis of atherosclerosis

Atherosclerosis is promoted by systemic factors, such as dyslipidemia, hypertension, diabetes, and smoking, which cause atherosclerosis in blood vessels throughout the body. However, atherosclerotic lesions are characterized by their frequent occurrence in specific vessels and sites. Blood vessels are exposed to various mechanical forces related to blood pressure and flow. Although shear stress promotes the initiation and progression of atherosclerotic lesions, the pathogenesis of site specificity of atherosclerosis is not sufficiently explained by shear stress. We propose the concept of a perivascular mechanical environment (PVME). Compelling evidence suggests that site specificity in atherosclerotic lesions depends on a distinct local PVME. Atheroprone arteries, such as the coronary artery, are markedly affected by externally applied mechanical force (EMF), whereas atheroprotective arteries, such as the internal thoracic artery, are less affected. Recent studies have shown that the coronary artery is affected by cardiac muscle contraction, the carotid artery by the hyoid bone and the thyroid cartilage, and the abdominal aorta and lower extremity arteries by musculoskeletal motion. We speculate that the thoracic cage protects the internal thoracic artery from EMF owing to a favorable PVME. Furthermore, evidence suggests that plaque eccentricity is provided by EMF; plaques are frequently observed on an external force-applied side. In each vascular tree, site-specific characteristics of the PVME differ substantially, inducing individual atherogenicity. From the perspective of the mechanical environment, hemodynamic stress occurs in an inside-out manner, whereas EMF occurs in an outside-in manner. These inward and outward forces apply mechanical load individually, but interact synergistically. The concept of a PVME is a novel pathogenesis of atherosclerosis and also might be a pathogenesis of other arterial diseases.

Popliteal entrapment syndrome: diagnostic, surgical management and short-term results of a ten-year experience

INTRODUCTION

Popliteal artery entrapment syndrome (PAES) is a rare cause of lower limb claudication in young sportsperson without cardiovascular risk factor. We reported our diagnostic approach, surgical management and short term outcomes of this syndrome, over a 10-year period.

MATERIAL AND METHOD

Sportsperson with intermittent claudication systematically received color duplex ultrasonography with dynamic maneuvers in the sport medicine department. In case of PAES suspicion, diagnosis was confirmed by dynamic computed tomography or dynamic magnetic resonance angiography. Each patient was then evaluated by a vascular surgeon and surgery was performed. We retrospectively screened patients who underwent PAES surgery between 2010 and 2020 in the department of surgery in Angers university hospital.

RESULTS

Between January 2010 and December 2020, 38 patients with 67 symptomatic legs underwent surgery for PAES. Twenty three (60.5%) were men. The mean age at the time of surgery was 24.7 +/- 9 years. Clinical presentation was bilateral in 30 patients (81.1%). Duplex ultrasound demonstrated severe stenosis or occlusion in 45 legs (77%). When performed, CT-scan demonstrated popliteal artery compression in all cases (100%). According to Whelan and Rich classification, 36 patients (94.7%) had type 6 PAES. There was no mortality or severe complication after surgery. Morbidity included 4 post-operative hematoma (6%) and 8 prolonged healing (13%). The mean time of follow-up was 2.3 months +/- 1.2 months. After surgery, D-scan showed no signs of remaining popliteal artery compression in 92.5% of the case. Twelve patients (33.3%) were able to resume sport, 18 (50%) partially and 6 (16.6%) did not resume sport yet.

CONCLUSION

We report a cohort of 38 patients who underwent surgery for popliteal artery entrapment syndrome. Among them, 36 (94.7%) were functional PAES. Morbidity included 13% of prolonged healing. Two months follow-up demonstrated good results at dynamic D-scan without signs of remaining popliteal artery compression in 92.5% of the cases. These short-term results showed that one third of patients able to resume sport activity at initial level.

Popliteal artery entrapment syndrome

Popliteal artery entrapment syndrome (PAES) is an uncommon cause of lower extremity exertional claudication due to external compression of vascular structures in the popliteal fossa. A developmental anomaly due to an aberrant relationship of the artery with the surrounding myofascial structures contributes to the vascular compromise. PAES presents in younger, athletic patients without atherosclerotic risk factors. Typical presentation of unilateral or bilateral, intermittent claudication in the feet and calves specifically after exercise and relieved by rest in a young person should prompt further evaluation. Early diagnosis and intervention is essential for preventing thromboembolic complication and in worst cases limb loss. Initial tests with Ankle Brachial indices or Doppler ultrasound with provocative maneuvers will prompt more definitive cross sectional imaging studies. CTA or MRA also with provocative maneuvers has a high sensitivity and specificity and will clinch the diagnosis. There are six subtypes based on the relationship of the vascular structure with surround myofascial structures. CTA and MRA can characterize the subtypes and guide surgical planning. Catheter directed thrombolysis may be attempted adjunctively to reduce surgical thrombectomy or resolve distal emboli; however, myotendinous decompression with or without vascular repair is the definitive treatment. Long term surgical outcomes are satisfactory when the distal circulation is preserved.

Popliteal artery entrapment syndrome: a case report with literature review

Popliteal artery entrapment syndrome generally causes calf claudication in young active adult. It is resulting of the anatomical relationship between the popliteal artery and adjacent muscles or fibrous bands in the popliteal fossa. We present the case of a 36-year-old male with left calf claudication limb in whom popliteal artery entrapment syndrome was diagnosed, and successfully treated surgically.

Kneeling-induced calf ischemia: a pilot study in apparently healthy European young subjects

PURPOSE

Many tasks, sports or leisure activities require maximal knee flexion. We hypothesized that this position could result in reduced calf perfusion, in young European subjects.

METHODS

We quantified calf ischemia resulting from the knee flexion with transcutaneous oxygen pressure (TcpO2) sensors by assessing the decrease from rest of TcpO2 (DROP) defined as limb changes minus chest changes. A minimal DROP (DROPm) <-15 mmHg defines the presence of ischemia. From the crawling position, participants kneeled for 3 min while bending as in prostration/prayer position (P). Thirty-five participants repeated this maneuver a second time, while 7 participants were also required to sit on their heels with the torso in the vertical position to attain knee flexion without significant groin flexion (S).

RESULT

In 41 healthy young volunteers (30 males), 25 [20-31] years old, 37 patients showed a DROPm < -15 mmHg from "R" to "P" in one (n = 4) or both (n = 33) calves (90.2%; 95% CI 76.9-97.3). After backward regression of the DROPm, there was no significant association with side, body weight of systolic blood pressure. However, age was strongly associated with DROPm (OR 5.34 [2.45-8.69]) so that DROPm was significantly higher in older, with a correlation ρ = 0.31 (p = 0.003).

CONCLUSION

Kneeling dramatically reduces calf perfusion, likely through popliteal artery kinking, possibly through muscle crushing. Eastern lifestyle includes routine flexed position since childhood. Whether or not such a chronic training reduces the risk of kneeling-induced ischemia in adults is unknown to date.

Popliteal entrapment syndrome-The case for a new classification

OBJECTIVES

To assess the ability of the current classification system for popliteal entrapment syndrome to accurately capture all patients, and if not, to design an all-inclusive new classification.

METHODS

Retrospective review of all interventions performed for popliteal entrapment syndrome between 1994 and 2013 at our institution was performed. Preoperative imaging and intraoperative findings were used to establish the compressive morphology of popliteal entrapment syndrome. Patients were categorized, when possible, into six types of the current classification system (Rich classification, modified by Levien) and into seven types of a new classification.

RESULTS

Sixty-seven limbs of 49 patients were operated on for unilateral (31) or bilateral (18) popliteal entrapment syndrome. The current classification system captured the anatomy of only 43 (64%) of 67 limbs with popliteal entrapment syndrome. Compressive morphologies without a defined class included aberrant insertion of the lateral head of gastrocnemius muscle, muscle slip originating from the lateral head of gastrocnemius or hamstrings, hypertrophied hamstring muscle, abnormal fibrous bands, perivascular connective tissue, and prominent lateral femoral condyle. The new classification captured 100% of the limbs with popliteal entrapment syndrome.

CONCLUSIONS

Current classification of popliteal entrapment syndrome is inadequate as more than one-third of the cases reviewed fell outside of the standard classification system. Consideration of a more inclusive new anatomic classification system is warranted.

Trapped by the Entrapment

Introduction

Popliteal entrapment syndrome results from extrinsic compression of the popliteal artery by the surrounding musculotendinous structures and is a rare cause of limb ischaemia. The purpose of this report is to highlight potential mistakes in the management of popliteal entrapment.

Report

In 2000, a 23 year old man underwent a popliteal to popliteal artery bypass surgery for what was initially diagnosed as a traumatic popliteal artery thrombosis. After being initially lost to follow up for 13 years, this “unspecified traumatic” thrombosis led to several inappropriate endovascular and open procedures misinterpreted as being caused by late graft failure. These included thrombectomy, aneurysmorrhaphy, polytetrafluoroethylene covered stent graft, a redo femoropopliteal bypass, and bypass thrombolysis. The diagnosis was reached 19 years after the initial surgery, when the patient underwent a redo bypass using a retrogeniculate approach. An abnormal lateral insertion of the gastrocnemius muscle medial head, and its accessory slip, constricted the artery, and also involved the popliteal vein (Type V), thus explaining previous revascularisation failures. Surgery consisted of resecting the accessory slip and the aneurysmal bypass. The artery was reconstructed with the cephalic vein. The patient was discharged on clopidogrel 75 mg, with no further complication, and a patent bypass at six months. Based on post-operative imaging (duplex ultrasound and magnetic resonance imaging), with forced plantarflexion and dorsiflexion, asymptomatic popliteal entrapment was also present on the contralateral side.

Discussion

The finding of an isolated popliteal artery lesion in a young individual should be considered to be caused by popliteal artery entrapment, unless proven otherwise. Definitive surgical release of the popliteal artery should be favoured over other strategies.

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Popliteal entrapment may be overlooked by confounding anamnestic factors, leading to inappropriate treatment.

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Popliteal entrapment should be ruled out in any isolated popliteal artery lesion in a young individual.

Functional Popliteal Artery Entrapment Syndrome: A Review of Diagnosis and Management

BACKGROUND

Functional popliteal artery entrapment syndrome (FPAES) results from hypertrophied gastrocnemius, soleus, and/or plantaris muscles, without an identifiable anatomic abnormality. Historically, FPAES has been managed with surgical myotomy or myomectomy. Herein, we review the literature to evaluate the results of surgery along with a newer treatment (botulinum toxin A injection) for this rare form of claudication.

METHODS

A literature search in PubMed, Cochrane, and Ovid for studies reporting incidence and management of FPAES yielded 3391 publications; 2804 articles were excluded based on initially established exclusion criteria. Ultimately, data were extracted from six articles, from which the number of patients, demographic information, preoperative workup, surgical treatment details, follow-up imaging, and results of treatment were obtained.

RESULTS

A total of 133 patients were studied. Mean age was 26 years; 57% were female, and noninvasive testing revealed bilateral findings in 39%. Treatment involved surgical myotomy/myomectomy (98; five studies) and botulinum toxin injection (35; two studies). Adjunctive vascular reconstruction was performed in eight of the surgical cases. Patients with FPAES who underwent surgical management were evaluated subjectively for symptomatic improvement, and some patients had duplex ultrasounds in follow-up averaging 25.6 months. Three of 98 patients (3%) had recurrent symptoms, and seven (7%) underwent revision surgical procedures. Complications in the surgical management group included seroma/hematoma (4%, 4/98) and infection (2%, 2/98). For the botulinum toxin treatment group, improvement of symptoms was achieved in 66% of patients at an average follow-up time of ten months. Most patients treated with botulinum toxin did not undergo imaging in follow-up. No complications were reported.

CONCLUSIONS

This review suggests FPAES may be treated successfully with surgical myotomy/myomectomy plus adjunctive vascular reconstruction if necessary. Botulinum toxin A injection may be useful as a diagnostic and therapeutic measure for FPAES.

Response of the popliteal artery to treadmill exercise and stress positioning in patients with and without exertional lower extremity symptoms

OBJECTIVE

Functionally limiting exertional lower extremity pain and neurologic symptoms are commonly encountered in military and civilian settings. Exertional muscle compression of the popliteal artery (PA) and tibial nerve in the proximal calf (the "popliteal outlet") can be associated with these symptoms but is rarely investigated as a cause. Exertional ankle-brachial index (EABI) and dynamic PA ultrasound imaging may be suitable to screen for this syndrome of "functional" popliteal entrapment, but neither has been rigorously studied. Our objective was to characterize the response of the PA to lower extremity exertion and dynamic ankle positioning in symptomatic and asymptomatic limbs.

METHODS

Limbs characterized as symptomatic (n = 29) or asymptomatic (n = 61) had duplex ultrasound PA diameter and peak systolic velocity measurements with the ankle neutral and maximally plantar flexed. EABIs were obtained at rest and 1 minute and 5 minutes after walking (5 minutes, 3 mph, 10-degree incline) and running (5 minutes, 6 mph, 0-degree incline). Significance was set at P ≤ .05. Data are expressed as mean ± standard error of the mean.

RESULTS

Plantar flexion resulted in PA occlusion and changes in diameter and peak systolic velocity in symptomatic (three occluded, -2.4 ± 0.34 mm, +49 cm/s) and asymptomatic (six occluded, -1.6 ± 0.21 mm, +65 cm/s) limbs. The difference in percentage change was significant between groups only for diameter change. EABIs in both groups were similar at rest, decreased with running and walking at 1 minute, and were not fully recovered by 5 minutes. Symptomatic limbs had a greater decrease in ABI than did asymptomatic limbs with both running and walking. The decrease was greatest at 1 minute after running and significantly more pronounced in symptomatic (-0.18) than in asymptomatic (-0.02) limbs.

CONCLUSIONS

EABI decrease at 1 minute after running and PA diameter decrease with dynamic ankle plantar flexion are significantly greater in limbs with than without exertional lower extremity symptoms. These noninvasive measurements may be valuable in the workup of such symptoms. PA and tibial nerve compression at the popliteal outlet may be a more frequent cause of functionally limiting exertional lower extremity pain and neurologic symptoms than previously recognized.

Popliteal Artery Entrapment Syndrome: A Case Report and Review of the Literature

BACKGROUND Popliteal artery entrapment syndrome (PAES) results from an anomalous relationship between the popliteal artery and the myofascial structures of the popliteal fossa. The most common presenting symptoms include intermittent pain in the feet and calves on exercise, resulting in lameness. PAES can lead to popliteal artery thrombosis, stenosis, distal arterial thromboembolism, or arterial aneurysm. The treatment of PAES includes surgical exploration with fasciotomy, myotomy, or sectioning of fibrous band formation, to release the popliteal artery. However, in cases with thrombotic occlusion, thromboendarterectomy with venous patch arterioplasty, or venous graft arterial bypass surgery may be required. This report describes the presentation and surgical management of a case of PAES presenting with limb pain and includes a review of the literature on this condition. CASE REPORT A previously healthy 47-year-old woman presented with a 20-day history of sudden pain in the left lower limb, associated with pallor and a loss of arterial pulses below the knee. Angiography of the affected limb showed occlusion of the left supragenicular popliteal artery, with arterial occlusion, suggestive of arterial thrombus. Imaging of the right popliteal artery, which was not occluded, showed that it was medially deviated. An ipsilateral saphenous vein graft was used to bypass the left supragenicular popliteal artery to the infragenicular popliteal artery, resulting in resolution of the patient's symptoms. CONCLUSIONS PAES is rare and can be under-diagnosed, possibly due to lack of knowledge of this condition. However, if the diagnosis is made early, the prognosis is usually favorable, following appropriate surgical treatment.

Functional popliteal artery entrapment syndrome: use of ultrasound guided Botox injection as a non-surgical treatment option

OBJECTIVE

To determine whether ultrasound-guided injection of botulinum toxin type A (BTX-A) is a viable alternative to surgical intervention for the treatment of functional popliteal artery entrapment syndrome (PAES).

MATERIALS AND METHODS

Twenty-seven patients met diagnostic criteria confirming the presence of functional PAES and agreed to go ahead with ultrasound-guided BTX-A injection at the level of artery occlusion. Patients were assessed and treated at baseline and given the option for 'top-up' injections at 6 and 12 months. Patients provided subjective symptom reports at 6 and 12 months post intervention.

RESULTS

No patients reported being worse off after the intervention; 59% of patients were categorized as having a good response (i.e., initial improvement that was maintained at 12 months), 22% a mixed response (i.e., an initial improvement that subsequently reduced over 12 months) and 19% a poor response (i.e., no difference) to treatment.

CONCLUSIONS

Ultrasound-guided BTX-A injection represents a viable alternative to surgery in the treatment of functional PAES. Further study will help determine the optimum dose and frequency of injection to prevent recurrence of symptoms.

Transient Acute Leg Ischemia in a Professional Athlete Caused by Isolated Popliteal Artery Dissection Mimicking Popliteal Entrapment Syndrome

Exertional leg pain includes a broad range of conditions induced by different vascular, musculoskeletal, and neurological disorders. We report a case with isolated popliteal artery dissection as a cause of a transient acute lower limb ischemia. We report a patient with popliteal artery dissection which occurred during squatting exercise. After initial signs of transient acute limb ischemia, physical and ultrasound examination pointed to entrampment syndrome as a likely cause. However, digital subtraction angiography showed possible dissection of popliteal artery, which was confirmed intraoperatively. Popliteal artery was resected and reversed saphenous vein bypass was performed. Isolated popliteal artery dissection in professional athletes is a rare entity, which can be manifested with exertional leg pain. Clinical findings can sometimes be similar to those of popliteal entrapment syndrome. Clinical suspicion and timely patient referral to a vascular specialist are crucial for optimal treatment of this limb-threatening condition.

Intravascular ultrasound as a novel tool for the diagnosis and targeted treatment of functional popliteal artery entrapment syndrome

Functional popliteal artery entrapment syndrome can be difficult to diagnose, as the imaging modalities presently employed are designed to detect anatomic entrapment. We describe a novel imaging technique to aid in diagnosis in this cohort. A 22-year-old cyclist presented with exercise-limiting claudication. Magnetic resonance angiography with provocative maneuvers was nondiagnostic. Digital subtraction angiography revealed long-segment occlusion of the popliteal artery with plantar flexion; however, the specific site of compression remained unclear. Intravascular ultrasound allowed specific localization of compression and further confirmed the diagnosis. Thus, we report this as an adjunctive imaging modality to definitively diagnose functional popliteal artery entrapment syndrome and to assist in operative planning.

Anatomical Popliteal Artery Entrapment Syndrome Caused by an Aberrant Plantaris Muscle

Purpose:

We report on cases of anatomical popliteal artery entrapment syndrome (PAES) caused by an aberrant plantaris muscle and highlight the involvement of this muscle in PAES.

Materials and Methods:

Seven symptomatic PAES legs in six patients treated at The Division of Vascular Surgery, Asan Medical Center, Seoul, Korea, between 1995 and 2011 were included in this study. We retrospectively analyzed patient records, magnetic resonance imaging (MRI) and/or computed tomography (CT) scans of the knee joint, Doppler pressure studies, CT angiographies, and conventional femoral arteriographies.

Results:

Five males and one female patient with a median age of 32 (18–53) years old were enrolled in the study. All patients complained of intermittent claudication of the affected leg. All aberrant plantaris muscles were higher and more medially located than normal plantaris muscles, causing occlusion of the popliteal artery upon forced plantar flexion of the ankle. For arterial lesions, five occlusions of the popliteal artery and two patent popliteal arteries with positive provocation were noted. As for treatment, myotomy of the aberrant plantaris muscle was done for two non-occlusive PAES legs. For occlusive PAES legs, one thrombectomy, one saphenous vein graft interposition of the popliteal artery followed by myotomy, and two below-knee femoro-popliteal bypasses were performed. The median follow-up period was 88 (7–148) months.

Conclusion:

An aberrant plantaris muscle can cause anatomical PAES. Classification or diagnosis of PAES should be based on axial studies using CT scans or MRI using various reconstruction methods. Treatment, including myotomy of the plantaris muscle, should be individualized.

Popliteal Artery Entrapment Syndrome: Report of 2 Critical Aspects Cases

Popliteal artery entrapment syndrome is a rare and underdiagnosed cause of claudication in young adult. The typical clinical feature is calf claudication; the following case reports describe 2 rare clinical aspects, acute limb ischemia and pulsatile mass revealing a bilateral anatomic entrapment. These cases suggest that an early diagnosis is mandatory to avoid a dramatic clinical outcome and to limit the surgical treatment to a myotomy.

Functional Popliteal Artery Entrapment Syndrome: Poorly Understood and Frequently Missed? A Review of Clinical Features, Appropriate Investigations, and Treatment Options

Functional popliteal artery entrapment syndrome (PAES) is an important and possibly underrecognized cause of exertional leg pain (ELP). As it is poorly understood, it is at risk of misdiagnosis and mismanagement. The features indicative of PAES are outlined, as it can share features with other causes of ELP. Investigating functional PAES is also fraught with potential problems and if it is performed incorrectly, it can result in false negative and false positive findings. A review of the current vascular investigations is provided, highlighting some of the limitations standard tests have in determining functional PAES. Once a clinical suspicion for PAES is satisfied, it is necessary to further distinguish the subcategories of anatomical and functional entrapment and the group of asymptomatic occluders. When definitive entrapment is confirmed, it is important to identify the level of entrapment so that precise intervention can be performed. Treatment strategies for functional PAES are discussed, including the possibility of a new, less invasive intervention of guided Botulinum toxin injection at the level of entrapment as an alternative to vascular surgery.

Between a rock and a hard place: clinical and imaging features of vascular compression syndromes

Vascular compression syndromes are caused by the entrapment of vessels between rigid or semirigid surfaces in a confined anatomic space. Chronic entrapment may lead to arterial ischemia and embolism, venous stasis and thrombosis, and hematuria. These syndromes are usually seen in otherwise healthy young patients, among whom underdiagnosis is common. Most occurrences of vascular compression are associated with an underlying anatomic abnormality. In a small percentage of cases, other contributing factors, including repetitive microtrauma, may cause pathologic changes leading to the onset of pain and other symptoms of vascular and neural compression. Hence, the diagnosis must be based on both clinical and radiologic findings. Because some cases of vascular entrapment become symptomatic only when specific physical maneuvers are performed, dynamic diagnostic imaging methods are especially useful. Digital subtraction angiography has been the mainstay of imaging-based diagnosis for most vascular compression syndromes, but other methods (eg, color Doppler ultrasonography, computed tomographic angiography, and magnetic resonance angiography) are used with increasing frequency for initial diagnostic evaluation. Because vascular compression syndromes are caused by the external compression of vessels, endoluminal treatment alone is rarely adequate and surgical decompression is likely to be required for optimal and durable clinical benefit. Supplemental material available at http://radiographics.rsna.org/lookup/suppl/doi:10.1148/rg.321115011/-/DC1.

Entrapment syndromes

Entrapment syndromes represent a pathological process that vascular specialists encounter infrequently. However symptomatic patients are often young with impaired quality of life and successful treatment can produce great benefit, making knowledge of these conditions essential. The purpose of this review was to bring together the entrapment syndromes to understand and gain consensus on the aetiology, pathogenesis, diagnosis and modern management of these rare and interesting vascular disorders. This includes entrapment syndromes of the popliteal artery, superior mesenteric artery, coeliac artery, renal vein and iliac vein.

Assessment of the medial head of the gastrocnemius muscle in functional compression of the popliteal artery

OBJECTIVE

Nonfunctional popliteal entrapment is due to embryologic maldevelopment within the popliteal fossa. Functional entrapment occurs in the apparent absence of an anatomic abnormality. Gastrocnemius hypertrophy has been associated with the latter. Both forms of entrapment may cause arterial injury and lower limb ischemia. This study assessed the attachment of the medial head of the gastrocnemius muscle in healthy occluders and healthy nonoccluders.

METHODS

Provocative tests were used to identify 58 nonoccluders and 16 occluders. Ten subjects from each group underwent magnetic resonance imaging evaluation of the popliteal fossa. The medial head of the gastrocnemius muscle attachment was assessed in the supracondylar, pericondylar, and intercondylar areas.

RESULTS

In the occluder group, significantly more muscle was attached towards the femoral midline (supracondylar), around the lateral border of the medial condyle (pericondylar), and within the intercondylar fossa.

CONCLUSION

The more extensive midline position of the medial head of the gastrocnemius in occluders is likely to be a normal embryological variation. Forceful contraction results in compression and occlusion of the adjacent popliteal artery. The clinical significance of these anatomic variations remains unclear. However, these new observations may provide insight for future analysis of the causes and natural history of functional compression and the potential progression to clinical entrapment.

Diagnosis and surgical approach of popliteal artery entrapment syndrome: a retrospective study

BACKGROUND

Popliteal artery entrapment syndrome (PAES) is a rare but potentially limb threatening peripheral vascular disease occurring predominantly in young adults. This study is a retrospective review of 49 limbs in 38 patients with PAES treated surgically over an 8-year period.

PATIENTS AND METHODS

From 1995 to 2002, 38 patients with a mean age of 21 years (range, 18-29 years) underwent surgery for PAES at a single institution. The patients' demographic data and clinical features are recorded. The preoperative diagnosis of PAES was made based on various combinations of investigations including positional stress test, duplex ultrasonography, computed tomography, computed tomographic angiography, and angiography.

RESULTS

Nine, 33, and 7 patients had Delaney's type I, II, and III PAES respectively. The surgical procedures consisted of simple release of the popliteal artery in 33 limbs (67.3%), autogenous saphenous vein (ASV) patch angioplasty with or without thromboendarterectomy (TEA) in 5 limbs (10.2%) and ASV graft interposition or bypass in 11 limbs (22.5%). At a median follow up of 34 months (range, 8-42 months), there were no postoperative complications and all the patients were cured of their symptoms.

CONCLUSIONS

PAES is an unusual but important cause of peripheral vascular insufficiency especially in young patients. Early diagnosis through a combined approach is necessary for exact diagnosis. Popliteal artery release alone or with vein bypass is the treatment of choice when intervention is indicated for good operative outcome and to prevent limb loss.

Bilateral popliteal artery entrapment syndrome: case report

Popliteal artery entrapment syndrome occurs due to an extrinsic compression of the popliteal vessels that results in vascular damage. It is one of the most frequent causes of intermittent claudication in young patients. The authors describe a case of bilateral syndrome by anomalous position of the gastrocnemius muscle, with abnormal slip of its medial head (Rich's type III). During the operation the occluded right side was reconstructed by autologous saphenous vein bypass from femoral superficial to peroneal artery and on the left side the slip muscle was transected by posterior approach. Popliteal artery entrapment syndrome should be treated by surgery despite the degree of symptoms. Surgical treatment technique has released the vessel by extracting the muscle that caused entrapment, and reconstructing the narrow lumen bypass grafting.

Bilateral Popliteal Artery Occlusion in a Competitive Bike Rider: Case Report and Clinical Review

Since its first description in 1879, popliteal artery entrapment syndrome remains a debilitating condition, which frequently affects young active people. Increased awareness of popliteal artery entrapment syndrome combined with improvements in investigative modalities has resulted in a more frequent diagnosis of this eminently treatable condition. In this article, a rare case of bilateral popliteal artery entrapment syndrome in a physically active 33-year-old man precipitated by competitive Bicycle Moto-Cross riding is presented. A higher index of suspicion for popliteal artery entrapment syndrome is recommended as the underlying pathology in a young active person with symptoms of lower limb claudication. Popliteal artery entrapment syndrome should be investigated with thorough radiological assessment prior to any therapeutic intervention, which is often fraught with difficulty due to chronically diseased vasculature and inherent anatomical anomalies.

Bilateral functional popliteal artery entrapment in a young athlete

Popliteal artery entrapment syndrome is a frequent cause of intermittent claudication in young patients. We present a case of a bilateral functional entrapment, where static imaging did not demonstrate the occlusion until the patient's feet were placed in forced plantar flexion. A high index of clinical suspicion and dynamic tests with provocative manoeuvres are needed to diagnose this condition.

[Atypical claudication and functional popliteal entrapment]

INTRODUCTION

Popliteal artery entrapment syndrome is infrequent. One form less well recognized has no anatomic abnormality.

CASE REPORT

A 22-year old man, with a medical history of chronic compartment syndrome treated surgically by aponeurectomy, had developed intermittent claudication of both legs with plantar paresthesia. Active plantar flexion of the ankle reduced distal pulses and doppler ultrasound waveforms. Popliteal artery entrapment syndrome was suspected and was confirmed by dynamic angiography. Because no arterial ou muscular abnormalities were found, we diagnosed a functional popliteal entrapment syndrome. Surgical treatment permitted rapid functional improvement.

DISCUSSION

Positional occlusion of the popliteal artery is a normal physiologic variant that may become pathologic with muscle overuse or traumatic injury. It causes neuromuscular claudication by compressing the neurovascular bundle at the level of the soleal sling. Diagnosis is based on dynamic color-flow duplex imaging and magnetic resonance angiography. Surgical treatment is indicated only for symptomatic patients and consists of fasciotomy, resecting the compressing structures with a posterior or medial approach.

Arteriographic evidence of pseudoocclusion of the popliteal artery: don't be fooled

Individuals with chronic lower extremity pain or lifestyle limiting claudication often undergo angiography prior to intervention. Occasionally initial angiographic findings are not indicative of a true pathologic process. Described below are two such cases. Both of the patients described had iliofemoral atherosclerotic disease with arteriographic suggestion of popliteal artery occlusion. However, their medical histories, noninvasive vascular studies, and arteriograms were not consistent with chronic popliteal artery occlusion. On subsequent arteriogram with knee flexion, the occlusions were found to be positional or pseudooccluded. Pseudoocclusion of the popliteal artery (POPA) does not require intervention, and therefore it is necessary to differentiate it from other pathologic processes. Discrimination of POPA from atherosclerotic occlusion, popliteal artery entrapment syndrome, cystic adventitial disease, and vasculitis is possible through history and exam. Arteriography is helpful because a lack of contralateral disease or collateral circulation may indicate a positional occlusion.

Popliteal vascular entrapment syndrome caused by a rare anomalous slip of the lateral head of the gastrocnemius muscle

Popliteal vascular entrapment syndrome can result in calf claudication, aneurysm formation, distal arterial emboli, or popliteal vessel thrombosis. The most commonly reported causes of this syndrome have been anomalies of the medial head of the gastrocnemius muscle as it relates to the course of the popliteal artery. We report two cases of rare anomalous slips of the lateral head of the gastrocnemius muscle causing popliteal vascular entrapment syndrome.

Non-traumatic lower limb vascular complications in endurance athletes. Review of literature

OBJECTIVES

To review the importance, clinical features, investigations, management and prognosis of non-traumatic vascular injuries, affecting the lower limbs of endurance athletes.

DESIGN

Review of literature.

MATERIALS AND METHODS

A literature search was conducted from Medline, Pubmed, the National Electronic Library for Health, Google and Yahoo search engines for related articles and case reports regarding non-traumatic vascular complications involving the lower limb of endurance athletes.

CONCLUSIONS

Non-traumatic vascular complications affecting the lower limbs include endofibrosis, stenosis/kinking of iliac arteries, dissection of external iliac artery, adductor canal syndrome, popliteal entrapment syndrome, chronic exertional compartment syndrome and effort-induced venous thrombosis. These are important as they affect athletes at the peak of their career and can be confusing to diagnose. The management is relatively well documented and produces good results in short term but the long term results are not known.

Popliteal artery disease: diagnosis and treatment

The popliteal artery is a relatively short vascular segment but is affected by a unique set of pathologic conditions. These conditions, which may be common throughout the arterial system or exclusive to the popliteal artery, include atherosclerosis, popliteal artery aneurysm, arterial embolus, trauma, popliteal artery entrapment syndrome, and cystic adventitial disease. The clinical manifestations, imaging appearances, and treatment options associated with these pathologic conditions differ significantly. Consequently, the radiologist should be familiar with these conditions to direct imaging for accurate diagnosis and treatment and to prevent loss of limb.

Clinical review of patients treated for atypical claudication: a 28-year experience

PURPOSE

This article describes patient demographic data, as well as diagnosis and treatment of symptomatic lower extremity claudication that has no apparent vascular or orthopedic cause.

METHODS

A retrospective review was performed of records for 843 patients who received surgical treatment between 1975 and 2003. All patients had a detailed history, and underwent physical examination and selected noninvasive vascular testing. Noninvasive popliteal entrapment screening tests and compartment pressure measurements for isolated superficial muscle pain were routine. Duplex scanning or arteriography were used only when arteriovenous disease or popliteal entrapment syndrome was suspected.

RESULTS

The study population included 549 female patients (65%) and 294 male patients (35%). Their mean age was 29 years (range, 12-71 years). The most common symptoms were isolated lower extremity muscle cramping (100%), foot paresthesia (20%), and medial tibial bone pain (1%). Causes of symptoms included chronic compartment syndrome (796 patients, 94%), functional popliteal entrapment syndrome (33 patients, 4%), and medial tibial syndrome (14 patients, 2%). Pathologic findings included overuse injury (756 patients, 89%), blunt limb trauma (60 patients, 7%), or gait anomaly (34 patients, 4%). Surgery for compartment release included fasciotomy (100 patients, 12%) or fasciectomy (696 patients, 88%). Surgery for functional popliteal entrapment included excision of the plantaris muscle and soleal band (33 patients). Medial tibial release included soleal and transverse fasciectomy, with periosteal cautery of the tibial insertions. Complete symptomatic relief was achieved in 92% of compartment release procedures, 100% of popliteal entrapment release procedures, and 80% of medial tibial release procedures.

CONCLUSION

Atypical claudication represents a collection of syndromes that can be permanently and effectively treated with surgical intervention.

Imagerie des pathologies vasculaires spécifiques

The diagnosis of vascularitis should be proposed when a concentric and regular thickening of the wall of the aorta or one of its branches is observed or when there is late enhancement of the arterial wall, on sites which are usually free from atheromatous lesions and in a young patient. The radiologist must be aware of the associated clinical signs: oral and genital ulcerative lesions in the Behçet syndrome; finger necrosis in a young male smoker in Buerger disease; hip and shoulder arthropathy and headache in a 70 Year old female and Horton disease; pulseless upper limbs and inflammatory syndrome in a young adult for the Takayasu arteritis. The diagnosis of popliteal entrapment or adventitial cyst should be proposed in young patients without atheromatous lesions.

Results of perioperative measurements of ankle-brachial index in popliteal artery entrapment syndrome

OBJECTIVE

The purpose of this study was to demonstrate whether there is postoperative improvement in blood flow in the affected limb after surgical decompression in popliteal artery entrapment syndrome (PAES). For this purpose, the simple method of measuring Doppler ankle pressure with and without provocation was used preoperatively and postoperatively.

PATIENTS AND METHODS

Doppler ankle pressure was measured preoperatively and postoperatively in neutral position (n=32) and with provocation (forced plantar flexion of the foot; n=32) in 32 limbs in 23 patients with PAES (19 men, 4 women; average age, 38.24 +/- 12.25 years) operated on between January 1, 1986, and December 31, 2000. The reference method was angiography with provocation in 18 patients and duplex ultrasound scanning in 14 patients.

RESULTS

Patients were assigned to one of two groups (A and B) on the basis of ankle-brachial index (ABI) at rest. Group A (mean age, 38.19 +/- 11.60 years) included all limbs (n=24) with ABI>0.9 preoperatively, and group B (mean age, 42.39 +/- 14.38 years) comprised all limbs (n=8) with ABI<0.9. Improvement in ABI under provocation after operation (group A, P<.0001; group B, P<.0004) was highly significant. In group B there was also a highly significant difference in ABI in the neutral position before and after operation (P=.0044); this could not be demonstrated in group A. Angiography or duplex sonography postoperatively did not provide any additional information.

CONCLUSION

Our results indicate that determination of ABI alone, with and without provocation, is sufficient as a postoperative follow-up examination to appraise decompression and for quality assurance of PAES. Compared with other more elaborate instrumental methods, measurement of ABI is relatively noninvasive, quick and easy to carry out, effective, and inexpensive.