Quantitative study of the popliteal fossa in the human fetus.

The popliteal fossa presents an extensive diamond-shaped topographical element on the posterior aspect of the knee. With the use of classical anatomical dissection, digital image analysis of NIS Elements AR 3.0 and statistics we morphometrically analyzed the size of the popliteal fossa in human fetuses aged 17-29 weeks of gestation. Morphometric parameters of the popliteal fossa increased logarithmically with fetal age: y = -44.421 + 24.301 × ln (Age) for length of superomedial boundary, y = -41.379 + 22.777 × ln (Age) for length of superolateral boundary, y = -39.019 + 20.981 × ln (Age) for inferomedial boundary, y = -37.547 + 20.319 × ln (Age), for length of inferolateral boundary, y = -28.915 + 15.822 × ln (Age) for transverse diameter, y = -69.790 + 38.73 × ln (Age) for vertical diameter and y = -485.631 + 240.844 × ln (Age) for projection surface area. Out of the four angles of the popliteal fossa the medial one was greatest, the inferior one the smallest, while the lateral one was somewhat smaller than the medial one and approximately three times greater than the superior one, with no difference with fetal age. In terms of morphometric parameters the popliteal fossa in the human fetus displays neither male-female nor right-left differences. In the popliteal fossa, growth patterns of its four boundaries, vertical and transverse diameters, and projection surface area all follow natural logarithmic functions. All the morphometric data is considered age-specific reference intervals, which may be conducive in the diagnostics of congenital abnormalities in the human fetus.

Heterotopic ossification in right popliteal fossa causing arterial insufficiency.

Heterotopic ossification (HO) is the abnormal formation of extra-skeletal bone in soft tissue, which can occur after trauma or surgery. HO in joints can cause pain, hinder mobility, and compress surrounding nerves and blood vessels. We present an unusual case of arterial insufficiency caused by HO in the right popliteal fossa.

Bilateral Gastrocnemius Tertius Muscles: Cadaveric Findings of a Rare Variant.

The posterior compartment of the leg typically contains three muscles in the superficial flexor group: the gastrocnemius, plantaris, and soleus. The gastrocnemius has medial and lateral heads (MH and LH) that originate from the medial and lateral condyles of the femur, respectively. However, a third head (TH) of the gastrocnemius, is a rare accessory muscle bundle of the gastrocnemius muscle that covers the surface of the popliteal fossa. Bilateral THs of gastrocnemius were identified in a 67-year-old male during a routine educational cadaveric dissection. Both gastrocnemius TH muscles consisted of a superficial belly with distinct neurovasculature heads and originated from the lateral condyle of the femur and inserted into the Achilles tendon. To our knowledge, the co-existence of bilateral gastrocnemius TH muscles has only been reported once. The male donor was found to exhibit an anatomical anomaly and could be clinically underdiagnosed due to its clinically silent nature and the lack of reports. Insight into the potential implications of bilateral and unilateral gastrocnemius TH and identification during clinical evaluation offers a path for future research to better identify and manage cases of gastrocnemius TH and its effects.

The influence of patient position on ultrasound examination of the sciatic nerve in the popliteal fossa: A cross-sectional study.

Introduction/Purpose: Ultrasound-guided popliteal fossa sciatic nerve (PFSN) blocks are performed with patients in the supine, lateral or prone position. No known studies compare the quality of images obtained from each approach. This study examines the quality of supine and prone PFSN ultrasound images. Methods: Thirty-eight adult volunteers were sorted into two groups. Five regional anaesthesiologists performed ultrasound examinations of the PFSN on volunteers in supine and prone positions. Popliteal fossa sciatic nerve image quality was analysed with grayscale techniques and peer evaluation. Popliteal fossa sciatic nerve depth, distance from the popliteal crease and time until optimal imaging were recorded. Results: The grayscale ratio of the PFSN vs. the background was 1.83 (supine) and 1.75 (prone) (P = 0.034). Similarly, the grayscale ratio of the PFSN vs. the immediately adjacent area was 1.65 (supine) and 1.55 (prone) (P = 0.004). Mean depth of the PFSN was 1.6 cm (supine) and 1.7 cm (prone) (P = 0.009). Average distance from the popliteal crease to the PFSN was 5.9 cm (supine) and 6.6 cm (prone) (P = 0.02). Mean time to acquire optimal imaging was 36 s (supine) and 47 s (prone) (P = 0.002). Observers preferred supine positioning 53.8%, prone positioning 22.5% and no preference 23.7% of the time. Observers with strong preferences preferred supine imaging in 70.9% of cases. Conclusions: Supine ultrasound examination offered quicker identification of the PFSN, in a more superficial location, closer to the popliteal crease and with enhanced contrast to surrounding tissue, correlating with observer preferences for supine positioning. These results may influence ultrasound-guided PFSN block success rates, especially in difficult-to-image patients.

Giant cutaneous squamous cell carcinoma of the popliteal fossa skin: A case report.

BACKGROUND: Cutaneous squamous cell carcinoma (cSCC) is a common malignant hyperplasia of the skin epithelium. However, cSCC progressing to giant squamous cell carcinoma of the popliteal fossa skin has not been reported. We used full-thickness skin graft from the lower left quadrant of the abdomen to reconstruct the popliteal fossa skin defect in our patient. CASE SUMMARY: A 64-year-old woman presented with a 3-year history of a progressively enlarged integumentary tumor located on her left popliteal fossa, which was surgically treated. The resultant defect (15 cm × 25 cm) was repaired using full-thickness skin graft from the lower left quadrant of the abdomen. CONCLUSION: Full-thickness skin graft is a good choice to repair popliteal fossa defect.

Posterior hamstring harvest improves aesthetic satisfaction and decreases sensory complications as compared to the classic anterior approach in anterior cruciate ligament reconstruction surgery.

PURPOSE: The use of the posterior approach for harvesting hamstring grafts has recently become popular thanks to new all-inside techniques and retrograde drills. This study aims to compare the classic anterior approach with the posterior approach in the popliteal fossa. METHODS: Retrospective comparative study of 100 consecutive cases of primary ligamentoplasty performed using ipsilateral semitendinosus autograft with at least one year of follow-up. 50 patients with anterior approach (group A) and 50 patients with posterior approach (P). Ratio men/women: 9/1. Mean age: 32 ± 13 years. Mean operative time: 64.88 ± 12.28 min. STUDY VARIABLES: Graft harvest time; intraoperative complications (semitendinous [ST] tendon cut); postoperative neurological complications (allodynia, paresthesia, pain) or hematoma in the donor area; atrophy of the operated thigh compared to the contralateral thigh, postoperative VAS score, aesthetic satisfaction and overall satisfaction. RESULTS: Graft harvest time of 9.5 min in group A versus 5.25 min in group P (p < 0.05). Sensory complications: 16% in group A versus 2% in group P (p < 0.05). Regarding the patient's evaluation of the aesthetic result of the surgery, 80% in group A and 92% in group P were very satisfied, 16% in group A and 8% in group P were satisfied and 4% in group A and no patients in group P not very satisfied (p < 0.05). No significant differences were found in terms of total operative time, postoperative joint movement, atrophy of the operated thigh, postoperative VAS, or overall patient satisfaction. CONCLUSIONS: The posterior approach to harvesting the ipsilateral hamstring graft obtained better results than the anterior approach in terms of aesthetic satisfaction of the patient, lower rate of neurological complications (allodynia, paresthesias and hypoesthesia in the anterior region of the knee and leg) and shorter hamstring harvest time. LEVEL OF EVIDENCE: IV.

Personalized Surgical Planning for Soft Tissue Sarcoma of the Popliteal Fossa with a Novel 3D Imaging Technique.

OBJECTIVE: Soft tissue sarcomas (STSs) arising from the popliteal fossa pose surgical challenges due to their proximity to critical neurovascular structures. This study aimed to investigate whether a novel 3D imaging technique highlighting these key anatomical structures could facilitate preoperative planning and improve surgical outcomes in STS. METHODS: This was a prospective, observational, pilot study. Between November 2019 and December 2020, 27 patients with STS of the popliteal fossa undergoing limb-sparing procedures were enrolled and assigned to either a control or intervention group. Control patients underwent traditional preoperative planning with separate computed tomography angiography, magnetic resonance imaging, and magnetic resonance hydrography. In the intervention group, 3D images were generated from these images, the tumor and skeletomuscular and neurovascular structures were revealed in three dimensions, and this was visualized on the surgeon's smartphone or computer. Primary endpoints were surgical margins and complications. Secondary endpoints included operative time, blood loss, serum C-reactive protein and interleukin-6, length of in-hospital stay, and limb function. Comparisons between groups were made using independent-sample t-tests for continuous data and the Mann-Whitney U and Fisher's exact tests for categorical data. RESULTS: There was a lower but not significantly different inadvertent positive margin rate (1/15 vs. 3/12, P = 0.294), significantly shorter hospital stay (P = 0.049), and less numbers ≥75th percentile of operative time (P = 0.037) and blood loss (P = 0.024) in the intervention group. Differences in surgical complications, operative time, blood loss, C-reactive protein and interleukin-6 levels on the second postoperative day, and limb functional scores were statistically insignificant. CONCLUSIONS: The novel 3D imaging technique facilitates complex preoperative planning and limb-salvage surgical procedures for patients with STS of the popliteal fossa, and this may affect how surgical planning is performed in the future.

Aneurisma poplíteo izquierdo / Left popliteal aneurysm

El aneurisma de la arteria poplítea es el principal aneurisma periférico y el segundo en frecuencia después del aneurisma de la aorta abdominal. Su incidencia se desconoce. Posee un patrón característico de presentación que corresponde a personas del sexo masculinos, mayores de 65 años, con múltiples comorbilidades, donde la hipertensión arterial representa la más frecuente. La definición de aneurisma corresponde a una dilatación del 50 por ciento del diámetro del vaso, en el caso de la arteria poplítea, mayor de 1,5 cm. El 50 por ciento de los aneurismas poplíteos resulta asintomático, el resto presenta síntomas isquémicos (trombosis, embolismos periféricos), compresivos y la ruptura. El tratamiento es quirúrgico: convencional (vías medial-posterior) y endovascular. El objetivo del artículo fue presentar este caso por la infrecuencia del aneurisma de la arteria poplítea unilateral. Se trata de un paciente masculino de 62 años, con aumento de volumen localizado a nivel de la fosa poplítea izquierda con latido y expansión a la palpación, diámetro transversal aproximado de 3 cm y longitudinal de 4 cm, presencia de soplo sistólico a la auscultación con diagnóstico ecográfico y arteriográfico de aneurisma de la arteria poplítea izquierda. La evolución del paciente fue satisfactoria y se mantiene bajo seguimiento médico para evaluar la permeabilidad del injerto sintético(AU)

Popliteal artery aneurysm is the main peripheral aneurysm and the second in frequency after abdominal aortic aneurysm. Its incidence is unknown. It has a characteristic presentation pattern that corresponds to male people, over 65 years of age, with multiple comorbidities, where arterial hypertension represents the most frequent. The definition of aneurysm corresponds to a dilation of 50 percent of the diameter of the vessel, in the case of the popliteal artery, greater than 1.5 cm. 50 percent of popliteal aneurysms are asymptomatic, the rest have ischemic symptoms (thrombosis, peripheral embolisms), compression and rupture. Treatment is surgical: conventional (medial-posterior pathways) and endovascular. The objective of the article was to present this case due to the infrequency of the unilateral popliteal artery aneurysm. This is a 62-year-old male patient, with localized volume increase at the level of the left popliteal fossa with heartbeat and expansion on palpation, approximate transverse diameter of 3 cm and longitudinal diameter of 4 cm, presence of systolic murmur at auscultation with ultrasound and arteriographic diagnosis of aneurysm of the left popliteal artery. The patient's evolution was satisfactory and he remains under medical follow-up to evaluate the permeability of the synthetic graft(AU)

A rare case of chronic pain and atraumatic inability to flex the knee: Evidence of a unilateral accessory popliteus muscle.

The literature describes a few case reports of bilateral accessory popliteus muscle, a rare variant of the popliteus muscle. We report a case of a 24-year-old male patient with acute pain and inability to flex the left knee, without a traumatic event. Additionally, the patient reported mild sensitive symptoms in the left calf region and no pain in the right knee. The patient underwent a series of other examinations which culminated in a Magnetic Resonance Imaging (MRI) that showed an accessory popliteus muscle. The comparative study of the contralateral knee showed no evidence of this anatomic variant.

Ultrasound-Guided CAPS (Crosswise Approach to Popliteal Sciatic) Block: A Novel Technique for Supine Popliteal Fossa Block.

The sciatic nerve block in the popliteal fossa is a popular lower extremity block for below-knee surgeries. Here the sciatic nerve is targated at or just above the point of its divergence into the tibial and common peroneal nerves. Amongst the described techniques, the supine approach of popliteal fossa block offers greatest patient comfort but has a few challenges accessing the nerve. We describe a novel ultrasound-guided distal transverse or crosswise approach to popliteal sciatic (CAPS) block performed in five patients in the supine position without unsteadiness of the knee or hip joint.

Cutaneous Actinomycosis of Popliteal Fossa: A Rare Case Report.

Introduction: Cutaneous actinomycosis of popliteal fossa is quite unusual, chronic granulomatous disease caused by a group of anaerobic or microaerophilic Gram positive filamentous bacteria that colonize the mouth, colon, and urogenital tract. Actinomycosis of popliteal fossa is rare clinical condition; therefore, recognition of this entity needs high degree of suspicion as the organism is specific internal habitant; primary involvement of extremities is rare. Case Report: This case report presents a rare case of actinomycosis of popliteal fossa (left side) in a 40-year-old male patient. The patient complained of presence of a mass with multiple pus oozing sinuses over popliteal fossa. The X-ray of leg revealed presence of foreign body. Histopathological examination of the biopsy from the lesions confirmed diagnosis of cutaneous actinomycosis. Conclusion: Cutaneous actinomycosis is a disease with great diagnostic challenge and requires high degree of suspicion for the early diagnosis which avoids unnecessary surgery and decreased morbidity and mortality.

A bilateral third head of the gastrocnemius which is morphologically similar to the plantaris.

PURPOSE: An extra muscle was observed on both sides of the popliteal fossa in the cadaver of a 78-year-old Japanese male during dissection. The aim of this case report was to identify whether this variant is a double plantaris or a third head of the gastrocnemius according to its morphological characteristics and innervation. METHODS: The muscles were displayed by careful dissection and delineation of surrounding structures. The size of each of the muscle bellies and tendons of those extra muscles were measured manually by the vernier caliper. RESULTS: The origin of each extra muscle was lateral to the tibial nerve and superior to the plantaris, and each extra muscle which transitioned to a descending tendon parallel to the plantaris had a cone-shaped belly. However, the tendon of the extra muscles was fused into the investing fascia of the gastrocnemius with a tendon length of 4.5 cm on the left and 4.6 cm on the right. The extra muscles were innervated by the branch of the tibial nerve to the medial head of the gastrocnemius on both sides. CONCLUSION: Although they had an origin and shape similar to that of the plantaris, we identified the extra muscles in this case as a third head of the gastrocnemius, because of innervation to the plantaris arises directly from the tibial nerve. This case highlighted that the innervation is essential to understanding the myogenesis of extra muscles, especially in cases which are difficult to categorize based on the morphological features of the muscle.

The determination of safe zones for arthroscopic portal placement into the posterior knee by mapping the courses of neurovascular structures in relation to bony landmarks.

PURPOSE: Minimally invasive surgery in the posterior knee is high risk for iatrogenic injury to popliteal neurovascular neurovasculature structures. This study aimed to use reliable landmarks to define safe zones for arthroscopic portal placement into the posterior knee. METHODS: Distances were measured between bony landmarks and neurovascular structures within the popliteal fossa using 45 formalin-embalmed cadavers: small saphenous vein (SSV), medial (MCSN) and lateral (LCSN) cutaneous sural nerves, tibial nerve (TN), common fibular nerve (CFN), popliteal vein (PV) and artery (PA). The structures were measured in relation to medial (MEF) and lateral (LEF) femoral epicondyle, medial (MCT) and lateral (LCT) tibial condyle and the midpoint between the landmarks. RESULTS: The mean distance (mm) between MEF and structures was, male and female, respectively: SSV 37.6 + 12.5, 37.9 + 8.2; MCSN 39.2 + 14, 38.8 + 10.1; TN 39.4 + 10.2, 38.0 + 8.1; PV 38.4 + 12.9, 32.8 + 5.6; PA 38.4 + 12.1, 34.6 + 4.9. At midpoint and MCT all structures medialized between 5 and 28%. The mean distance between LEF and structures was, male and female, respectively: CFN 13.4 + 8.2, 8.4 + 9.1; LCSN 24.9 + 7.3, 18.4 + 10.4. At midpoint and LCT the CFN lateralized by 37-42% and the LCSN medialized by 8-9%. CONCLUSIONS: Results suggest posteromedial portal placement can be safely established < 20 mm from the medial femoral epicondyle, tibial condyle or the midpoint between the two landmarks. Posterolateral portal placement is of higher risk, and entry point is 18 mm from the lateral femoral epicondyle, tibial condyle or the midpoint between the two landmarks in males and 12 mm in females. These landmarks will allow safe portal placement in 99% of cases.

Bilateral Sciatic Nerve Compression Due to Abnormal Termination of the Small Saphenous Vein Into the Popliteal Vein: A Rare Mechanism of Pseudoclaudication of the Lower Extremities.

Claudication in the young population is a rare condition derived from varied neurogenic and vascular conditions. We report a case of bilateral claudication of the lower extremities in a young athlete after intense training. Apart from tenderness to deep palpation of the popliteal fossa, physical and laboratory examinations did not reveal any abnormal findings. According to the patient's symptoms, sciatic nerve entrapment to the popliteal fossa was suspected and bilateral surgical exploration of the sciatic nerve was performed. The sciatic nerve was found to be entrapped before its division to the tibial and common peroneal nerves from the terminal branch of the small saphenous vein (SSV) into the popliteal vein (PV). The terminal section of SSV was subsequently ligated and resected to relieve the pressure on the sciatic nerve. One year after surgery, the patient was able to run long distances as well as sprint and train without any restriction. Rare conditions may lead to pseudoclaudication in young individuals and athletes during exercise. Normal physical and laboratory tests must raise the suspicion of sciatic nerve compression from fibrous bands or abnormal anastomotic veins that may also exist bilaterally. Surgical exploration along with sciatic nerve release remains the only treatment solution when conservative treatment fails to alleviate the symptoms.

Popliteal fossa reconstruction with medial genicular artery flap in a low resource setting: A report of two cases.

BACKGROUND: Popliteal fossa defects are common arising from several causes. Options of reconstruction around the knee could be limited by the cause of defect or interventions. Medial genicular artery flap is known in the books but not in popular use despite its obvious advantages of superior vascularity, adequate size, suppleness, and hidden donor site. AIM: To promote the use of this flap due to its advantages and ease of use especially in resource poor settings. PATIENTS AND METHODS: We report two patients from a low resource setting aged 23 and 20 years respectively. The first case was managed for avulsion wound of the popliteal fossa while the second had post burn knee contracture release. The resultant large popliteal fossa defects on both patients were seen on clinical examination. Both patients were offered popliteal fossa reconstruction for the popliteal fossa defects using medial genicular artery flap with good outcome. CONCLUSION: The medial genicular artery flap is a veritable option of popliteal fossa reconstruction especially for defects that are located contiguous to the flap and when other regional flap options are not available. Flap survival is excellent and donor site is hidden.

Tibial Nerve Schwannoma: An Unexplained Cause of Lateral Foot Pain - A Rare Case Report and Review.

INTRODUCTION: Schwannoma is a benign tumor that arises from the peripheral nerve sheath. It presents as a discrete, often tender, and palpable nodule associated with neurogenic pain or paresthesia when compressed or traumatized. The growth rate is usually slow, and these lesions seldom exceed 2 cm in diameter. CASE REPORT: We report the case of a schwannoma arising from the tibial nerve located in the left popliteal fossa. The patient presented with the left foot pain in the lateral plantar region without any motor deficit. The pre-operative diagnosis was made with magnetic resonance imaging (MRI) scan. He was subjected for neurolysis and excision biopsy of the lesion. The surgical specimen consisted of encapsulated white-yellow mass with irregular contours, measuring 2 × 3 cm. The cut section revealed cystic degenerations with areas of hemorrhage and necrosis. The patient reported symptom free in the post-operative period and during follow-up. Marginal excision appears to be recommended therapy for this tumorous lesion, without any evidence of recurrence during follow-up. CONCLUSION: A benign nerve sheath tumor of a peripheral nerve could be a possibility for long-standing neuropathic pain in the foot, ankle, and leg, wherein all other possibilities have been ruled out. The meticulous examination of the entire length of the tibial nerve including sciatic nerve by palpation and percussion was helpful in diagnosis which should be confirmed by MRI scan. The excision biopsy remains the gold standard treatment of choice for schwannoma of the peripheral nerve.

A case report of metastatic melanoma in the popliteal fossa.

INTRODUCTION: Metastatic melanoma in the popliteal fossa is extremely rare with less than 5% of metastatic deposits from melanomas in the leg and foot draining into the popliteal region, while the majority drain to the inguinal region. If popliteal spread is clinically overlooked, it may lead to recurrence. Together with the accompanying literature review, this case report emphasises the need for thorough clinical and radiological assessment in the management of malignant melanomas of the lower extremity. PRESENTATION OF CASE: A 66-year-old gentleman presented with metastatic melanoma to the right popliteal fossa three years after the diagnosis of a primary lesion in the right mid-calf with ipsilateral inguinal lymph node metastasis for which he underwent a right wide local excision and complete groin lymph node dissection. DISCUSSION: Studies show that a lesion anywhere below the knee can metastasize to the popliteal fossa. The groin can be the primary or secondary lymphatic drainage site in conjunction with the popliteal fossa. Concurrent popliteal and inguinal drainage may either reflect two separate lymphatic channels with popliteal nodes being the primary drainage site, or a single channel which drains to the popliteal basin as an interval node. Hence, popliteal lymph nodes should be carefully assessed in distal lower extremity lesions including melanomas. Modalities to delineate lymphatic flow and identify micrometastatic deposits should be used and when metastatic popliteal disease is identified, radical popliteal dissection is advised. CONCLUSION: Proper clinical assessment, good surgical technique, a high index of suspicion, and active surveillance are all essential to ensure early detection of metastasis to the popliteal region.

Feasibility of Point Shear Wave Elastography for Evaluating Diabetic Peripheral Neuropathy.

OBJECTIVES: In the mode of Virtual Touch quantification (Siemens AG, Erlangen, Germany), point shear wave elastography (p-SWE) is widely used for noninvasive assessments of tissue stiffness, which may be useful in the evaluation of diabetic peripheral neuropathy (DPN). METHODS: Thirty patients with type 2 diabetes and 20 control participants (7 with myoma of the uterus and 13 with kidney stones) were enrolled in this prospective study. The 30 patients were further divided into patients with DPN and patients without DPN. Conventional ultrasound examinations and p-SWE were used to examine the tibial nerve in the popliteal fossa. RESULTS: Tibial nerve stiffness values in the overall patient group, patients with DPN, and patients without DPN were all significantly higher than in the control group (P < .05). The cutoff value of p-SWE for assessing DPN was 2.60 m/s; at that threshold, sensitivity was 63.33%, and specificity was 92.50%. CONCLUSIONS: Point SWE was useful for the noninvasive assessment of DPN and had high specificity. The increased stiffness in patients without DPN indicated that the tibial nerve might be affected by diabetes.