Surgical management of functional popliteal entrapment syndrome in athletes

Contemporary outcomes of surgical decompression for functional popliteal entrapment syndrome

BACKGROUND

Functional popliteal entrapment syndrome (FPES) is an under-recognized source of leg pain caused by dynamic compression of the popliteal vessels by surrounding musculature in the absence of anatomic abnormality. Late recognition and difficulty capturing this entity across imaging modalities can lead to significant morbidity in an often young and active patient population. Surgical outcomes and optimal diagnostic strategies remain uncertain.

METHODS

We performed a retrospective cohort study of all patients undergoing surgical decompression for FPES at an academic medical center between 2018 and 2022. Preoperative symptoms, patient characteristics, imaging, operative details, and follow-up were captured. The primary outcome was symptomatic improvement at last clinic visit. Secondary outcomes included symptomatic improvement at 6 months and postoperative complications.

RESULTS

A total of 24 extremities (16 patients) were included. The mean ± standard deviation age was 23.3 ± 6.4 years and 75.0% of patients were female. The median symptom duration before decompression was 27 months (interquartile range, 10.7-74.6 months). Preoperative symptom severity in the affected extremity was as follows: 33.3% limited from peak exercise, 25% unable to exercise, and 41.7% with debilitating symptoms that affected activities of daily living. Preoperative imaging with provocative maneuvers included duplex ultrasound (87.5%), magnetic resonance angiography (100%), and digital subtraction angiography (100%). Using digital subtraction angiography as the gold standard, the sensitivity for detection of FPES was 85.7% for duplex examination and 58.3% for magnetic resonance angiography. The median follow-up was 451 days (interquartile range, 281-635 days). Most patients demonstrated durable improvement in the affected extremity, with 29.2% realizing complete resolution of symptoms and 37.5% reporting symptomatic improvement at last clinic visit for a total of 66.7%; 20.8% had initial improvement, but developed recurrent symptoms and were found to have elevated compartment pressures consistent with chronic exertional compartment syndrome and were treated with formal fasciotomy. Repeat decompression was required in one extremity (4.2%) owing to recurrent symptoms. Two patients (8.3%) had minimal or no improvement in their affected extremity and workup for the cause of continued discomfort was ongoing.

CONCLUSIONS

Delays in diagnosis of FPES are common. Provocative maneuvers until replication of symptoms across multiple imaging modalities may be necessary to reliably identify the disease process. Surgical decompression improved or completely resolved symptoms in two-thirds of extremities. Treating physicians should maintain suspicion for comorbid chronic exertional compartment syndrome, especially if symptoms recur or persist after decompression.

A Rare Case Report of Exertional Leg Pain

ABSTRACT

The accurate diagnosis of exertional leg pain in athletes is often delayed because of vague presenting symptoms and nonspecific physical examination findings. This case report outlines exertional leg pain in a runner caused by combined popliteal artery entrapment and soleal sling syndromes, 2 uncommon causes of exertional leg pain. This case report highlights the overlapping clinical presentation of these 2 diagnoses and the intricate differences in diagnostic workup and surgical approach to management.

Dynamic Imaging is the Ideal Modality for the Diagnosis of Popliteal Artery Entrapment Syndrome

BACKGROUND

Popliteal Artery Entrapment Syndrome (PAES) is a rare vascular condition with significant equipoise on how to properly diagnose and evaluate relevant imaging. This can lead to misdiagnosis and delay in surgical management. The objective of this study is to describe and compare distinct imaging features of dynamic versus static images to help determine the ideal imaging modality for diagnosis of PAES.

METHODS

This is a retrospective review of patients referred for PAES at a single institution. We reviewed noninvasive imaging studies, diagnostic arteriograms, and cross-sectional images which include computed tomography angiography (CTA) or magnetic resonance angiography (MRA). For each affected and unaffected extremity, the characteristic collaterals for PAES were named and measured on arteriogram using Picture Archiving and Communication Software. Available cross-sectional images were also analyzed and compared with arteriogram and intraoperative findings during surgical exploration.

RESULTS

There were 23 patients referred for PAES who underwent diagnostic evaluation and surgical management between 2013 and 2022. All patients had a duplex ultrasound that revealed a mean popliteal peak systolic velocity of 78 cm/sec at rest. With forced plantar flexion, the peak systolic velocity increased to a mean 175 cm/sec. A total of 12 extremities had complete loss of flow with provocation during duplex ultrasound. All patients underwent diagnostic angiography of 46 extremities. All limbs with PAES (n = 35) exhibited complete popliteal artery occlusion during angiography with forced plantar flexion. Distinct angiographic findings on resting images included a well-developed medial sural artery in 100% of limbs with PAES with a mean diameter of 2.7 mm. In limbs without PAES, only 80% had a visualized medial sural artery on arteriogram with a mean diameter of 2.0 mm (P = 0.1). A lateral sural artery was seen in 85% of affected extremities (mean diameter of 1.8 mm), while an anterior tibial recurrent artery was seen in 59% of affected extremities (mean diameter of 1.3 mm). In unaffected limbs, there were no visible lateral sural or anterior tibial recurrent arteries. The mean contrast used with diagnostic arteriograms was 58 milliliters (range 10-100 milliliters). Axial imaging was available for 9 affected extremities. Five had a previous MRA with only 1 being truly positive for arterial compression. Four extremities had previous CTA with 3 being falsely negative despite having type 3 PAES discovered during surgical exploration.

CONCLUSIONS

Dynamic imaging with angiography provides immediate surgeon feedback by visualizing popliteal artery compression and enlarged sural collaterals during resting arteriography. The medial sural collateral is enlarged in patients with PAES and often the lateral sural and anterior tibial recurrent arteries can be visualized as well. CTA and MRA are associated with high false-negative rates, and therefore cause delays in diagnosis and surgical management of PAES. Dynamic imaging should, therefore, be the gold standard for the diagnosis of PAES.

Long-Term Functional Outcomes After Surgery of Functional Popliteal Artery Entrapment Syndrome

BACKGROUND

Functional popliteal artery entrapment syndrome (fPAES) is a subtype of PAES without anatomic abnormalities entrapment of the popliteal artery. One of the management of symptomatic fPAES is surgical exploration of the popliteal region with popliteal artery release with lysis of fibrous bands. There is a lack of data regarding the long-term functional results of this surgery, most of the studies focusing on vascular patency in anatomical PAES. The aim of this study was to assess the efficacy of surgery in functional PAES, focusing on long-term physical activity return after surgery with the Tegner activity scale.

METHODS

All patients who underwent surgery for fPAES from January 1, 2010, to December 31, 2020, were searched. After ethical approval, all patients were called to evaluate physical activity since surgery. The Tegner activity scale is a numerical scale with each value (0 to 10) representing specific activity. The aim was to evaluate everyday activity limitations and participation restriction after surgery. The results for each patient were recorded: "before symptoms," "before surgery," and "after surgery."

RESULTS

Over the study period, 33 patients were included with 61 symptomatic legs. The mean time between surgery and phone call was 38.6 ± 21.9 months. The median score of the Tegner activity scale "before symptoms" was 7 (4-7), the median score "before surgery" was 3 (2-3), and the median score at the time of the phone call "after surgery" was 5 (3-7). P value was <0.0001 by comparing results "before surgery" and "after surgery."

CONCLUSIONS

Results demonstrated that the sport activity and intensity level is significantly higher after surgery even if patients did not reach their initial sport activity level.

Surgical Treatment for Popliteal Artery Entrapment Syndrome in Japan: a Retrospective, Multicentre Study Using a National Clinical Registry

OBJECTIVE

Surgical treatment is an established method for popliteal artery entrapment syndrome (PAES), which, however, mainly derives from single centre experiences where PAES cases are centralised and treated periodically. This study evaluated clinical outcomes of surgical treatment for PAES in a clinical setting where PAES cases were not centralised.

METHODS

Multicentre, retrospective cohort study using a national clinical registry. From a Japanese nationwide clinical registry, data for patients who underwent surgical treatment for PAES between 2013 and 2018, including 58 limbs from 41 institutes, were retrieved and evaluated. Patency was analysed using Kaplan-Meier curves.

RESULTS

The mean patient age was 36 ± 19 years, 78% were male, and the incidence of PAES was 0.24 limbs/centre/year, reflecting a clinical setting where PAES cases are not centralised. The most frequent arterial symptom was intermittent claudication (90%). Computed tomography was performed in 57 limbs (98%) for the diagnosis, however active manoeuvres such as dorsiflexion and plantarflexion during the examination was performed in only 13 limbs (22%), and occlusion of the popliteal artery was present in 38 limbs (66%) at diagnosis. Regarding surgical treatment, myotomy alone was performed in only seven limbs (12%), and other limbs were revascularised. Mean follow up was 26 ± 20 months, and surgical treatment was effective as it relieved symptoms in > 96% of limbs, with five year primary and secondary patency of the surgical treatment for PAES of 72% and 93%, respectively.

CONCLUSION

Results of surgical treatment were acceptable even in a clinical setting where PAES cases were not centralised. However, a low incidence of active manoeuvres performed during the examination and a high incidence of occlusion at diagnosis suggests there may be delayed or underdiagnosis of PAES in Japan, and increased awareness for PAES is warranted.

Optimizing the diagnostic approach of functional popliteal artery entrapment syndrome

OBJECTIVE

Functional popliteal artery entrapment syndrome (fPAES) is an underdiagnosed and undertreated etiology of atypical claudication. Symptoms of fPAES include deep posterior muscle cramping and pain with exercise and, unlike anatomic PAES, there are seldom vascular complications. Common noninvasive diagnostic modalities include ankle-brachial index, arterial duplex Doppler ultrasound (DUS) examination, and cross-sectional imaging such as magnetic resonance angiography (MRA). Entrapment can be difficult to reproduce during diagnostic testing, requiring provocative maneuvers. Because we believed different provocative maneuvers provide different diagnostic efficacy, we sought to optimize our diagnostic approach to fPAES.

METHODS

We performed a retrospective review of patients before and after optimizing our noninvasive imaging protocol comparing patients with fPAES versus other atypical claudicants with chronic compartment syndrome.

RESULTS

Arterial DUS examination and exercise ankle-brachial index were important components of our protocol with a significant decrease in systolic posterior tibial blood pressure of -14 mm Hg after exercise, whereas nonentrapment release patients had an overall increase of 8 mm Hg (P = .006). Arterial DUS examination of the distal PA with forced plantarflexion demonstrated a trend toward an increase in the measured velocity ratio, especially in the middle and distal PA. MRA with stressed plantar flexion findings were positive in 6 of 11 patients with fPAES, with false negatives likely owing to patients' inability to maintain a provocative position for the duration of the MRA.

CONCLUSIONS

Diagnosing fPAES is challenging owing to a lack of standardized diagnostic testing and provocative maneuvers. Different maneuvers demonstrated varying diagnostic yields for fPAES. Exercise ABIs were the most reliable vascular laboratory test to detect changes attributable to fPAES and to distinguish it from chronic compartment syndrome. Segmental PA DUS examination seems to be promising as a means of detecting PA impingement. Stress positional MRA effectively demonstrates anatomic PAES, but has a false-negative rate for fPAES.

Popliteal Artery Entrapment Syndrome: A Diagnostic and Treatment Enigma for Orthopaedic Surgeons

Popliteal artery entrapment syndrome (PAES) is an uncommon condition that causes recurrent posterior leg pain and foot paresthesia in running athletes. This condition occurs most commonly due to an accessory or abnormal implant of the medial head of the gastrocnemius muscle. It may mimic or coincide with other chronic conditions of the lower extremity including chronic exertional compartment syndrome but is most consistent with vascular claudication. Clinical features that distinguish PAES from other causes of leg pain include a sensation of coolness of the posterior leg during exercise and associated paresthesia of the plantar aspect of the foot. Physical examination often reveals decreased intensity of the posterior tibial or dorsalis pedis pulses with passive dorsiflexion or active plantarflexion of the ankle. Diagnostic tests that confirm the presence of PAES include lower extremity angiography during active resisted plantarflexion or maximal passive dorsiflexion, and magnetic resonance angiography done after exercise provocation. Nonsurgical treatment with physical therapy and stretching of the gastrocnemius complex should be done as the first line of treatment. When conservative treatments are ineffective, referral to a vascular specialist for surgical intervention with a muscular band excision or transection, vascular bypass, or arterial reconstruction is necessary.

Functional Popliteal Artery Entrapment Syndrome: An Approach to Diagnosis and Management

Popliteal Artery Entrapment Syndrome (PAES) is an uncommon syndrome that predominantly affects young athletes. Functional PAES is a subtype of PAES without anatomic entrapment of the popliteal artery. Patients with functional PAES tend to be younger and more active than typical PAES patients. A number of differential diagnoses exist, the most common of which is chronic exertional compartment syndrome. There is no consensus regarding choice of investigation for these patients. However, exercise ankle-brachial indices and magnetic resonance imaging are less invasive alternatives to digital subtraction angiography. Patients with typical symptoms that are severe and repetitive should be considered for intervention. Surgical intervention consists of release of the popliteal artery, either via a posterior or medial approach. The Turnipseed procedure involves a medial approach with a concomitant release of the medial gastrocnemius and soleal fascia, the medial tibial attachments of the soleus and excision of the proximal third of the plantaris muscle. Injection of botulinum A toxin under electromyographic guidance has recently shown promise as a diagnostic and/or therapeutic intervention in small case series. This review provides relevant information for the clinician investigating and managing patients with functional PAES.

Incidence, diagnosis and treatment of popliteal artery entrapment syndrome in current vascular practice in Japan

Few data regarding popliteal artery entrapment syndrome (PAES) is available in Japan. In this study, we investigated incidence, diagnosis and treatment of PAES in current vascular practice. A retrospective analysis of all patients with PAES visiting 31 participating institutes between 2003 and 2015 was conducted. Thirty-five limbs (28 patients) were identified during the 13-year study period, and the incidence of PAES was 0.12% of all peripheral artery disease cases revascularized. Mean age was 32.0 ± 16.9 years old, and 60 and more years old was 10.7%. Also, 92.9% were male and 39.3% were athletes. Most frequent initial symptoms were intermittent claudication in 23 limbs (65.7%); 4 limbs (11.4%) had chronic limb-threatening ischemia. CT scan was most frequently (94.3%) used for the diagnostic imaging followed by MRI (45.7%) and duplex ultrasound (45.7%). Stress test such as dorsal flexion during duplex ultrasound was used only in 28.6%. Thirty-two limbs (91.4%) received surgical treatment, including 23 arterial reconstructions (71.9%); there were no major perioperative complications. All patients achieved improvement of their symptoms, and the average ankle brachial index increased from 0.69 ± 0.22 to 1.00 ± 0.14 post-surgery. The average postoperative follow-up period was 26.0 months with only one reintervention during the follow-up. In conclusion, PAES was a rare condition and traditional surgical treatment was solid. However, given a broad spectrum of clinical feature of PAES and less usage of diagnostic duplex ultrasound with stress test, there might be a miss- or delayed diagnosis of PAES even in the current vascular practice.