Search

Objectives: A profound knowledge of the anatomical organization of adductor muscle compartment is necessary to understand their functions, and to assist in the development of accurate clinical and biomechanical models. This study aims at providing appropriate morphometric measurements of adductor longus muscle. Materials and Methods: The present study was conducted on 50 lower limbs. All limbs were fully dissected and measurements were taken with help of a steel tape. Results: We found Adductor longus muscle in all the 50 dissected lower limbs (100%). The range of length and width of proximal aponeurosis varied from 4.1- 6.8cm and 0.8 -2.5cm respectively. The range of length of fleshy part (muscular belly) varied from 14.4 – 20.7cm. The range of length and width of distal aponeurosis varied from 9.8 – 13.9cm and 2.1 – 4.8cm respectively. Conclusion: Our results would aid educational anatomy dissections, surgical interventions and help in management of many ailments. Keywords: Cadaver, Adductor longus, Morphometry.

Objective This case report illustrates an unusual cause of hip adductor muscle injury due to overenthusiastic self-treatment of the previously overloaded adductor muscles. Also, post-injury therapeutic objectives and intervention to facilitate rapid participation in sports after the described process are provided. Case description A 27-year old male, professional soccer player presented with hip adductors pain and impairment due to electromechanical self-treatment of the affected area. He was evaluated using hip-strength assessments, self-report, ultrasonography (US), and magnetic resonance imaging (MRI) until complete functional recovery had occurred. Along with clinical presentation, diagnostic imaging showed evidence of an isolated injury to the adductor longus muscle. A well-structured rehabilitation and readaptation program was followed in order to ensure early recovery and optimal functional outcome. Outcomes The athlete was able to participate in a full soccer training session without any limitation 18 days after his self-treatment session. The patient returned to his previous level of performance by 3rd week post-injury. Conclusion To the authors’ knowledge, this is the first report of muscle strain due to overenthusiasthic therapy. Although this is a rare complication of self-treatment procedures, patients and therapists should be aware of this risk in order to prevent and rapidly identify the lesion.

Aim. The article aims to explore the features of a ball kicking bioelectric activity of lower limbs muscles in students playing snow football. Materials and methods. 30 males aged 21–25 years old were examined (3–4-year students): the control group consisted of 15 people playing football; the main group included 15 people playing snow football. Athletes kick a ball on a normal and on a slippery surface, imitation of a slippery surface was carried out using a GYMSTICK Power Slider 61131-PRO slide board. To record the bioelectric activity of the muscles, the Neuro-MVP-4 multifunctional computer system was used (Neurosoft, Ivanovo, Russia). The bioelectric activity of the calf muscles (the medial lateral head of the calf muscle), the rectus femoris muscle, and the adductor longus muscle was studied. Results: It has been shown that athletes playing football and snow football have different and largely opposite motor stereotypes of intermuscular coordination when kicking the ball in usual conditions. When this action is repeated under unusual conditions, stereotype distortion is observed. Football players are characterized by a partial stereotype distortion, while people playing snow football are almost completely disorganized on a normal surface. Conclusion: Football training for students playing various types of football should be carried out in different conditions and implement various strategies. In particular, it should be aimed at various muscle groups. Ball kicking in unusual conditions should be used carefully, as this can be accompanied by a negative transfer of skills and reduce the effectiveness of athletes’ performance.

“Hydatid cyst” which also known as cystic Echinococcosis is a parasitic infestation caused by the larval stage of Echinococcus granulosus. The liver and lungs are the most sites to occur. Incidence in muscles is exceptionally rare. We report a case of a 36-year-old female presented with an uncomfortable mass in the upper medial of her right thigh without any presence of other symptoms. She lived in a rural area in Manbij, which is an endemic area of hydatid cysts in Syria. She was a shepherdess; therefore she had direct contact with sheep and dogs. Ultrasound examination showed a cyst located between adductor longus muscle and gracilis muscle closed to the deep femoral artery. The patient was treated with pharmaceutical therapy for a week before cystectomy, which was done under general anesthesia. The cyst was dissected between the fibers of adductor longus muscle from the lateral side and fibers of the gracilis muscle from the medial side. The cyst with all its layers was resected. Musculoskeletal Echinococcosis is a rare disease, because of intramuscular growth of cysts is restricted by muscle's contractility, the muscles are undesirable habitat for Echinococcus granulosus and because of the hepatic barrier role. Many cysts are revealed by complications such as nerve compressions, infections simulating an acute abscess or a malignant tumor. Hydatid cyst present as mass of soft tissue, particularly in endemic areas, as a result of contaminated water. MRI considered the best technique in the diagnosis., Highlights • Incidence of Hydatid cyst in muscles is exceptionally rare. • MRI considered the best technique in the diagnosis. • Confirming the final preoperative diagnosis of muscle hydatid cysts is important. • Hydatid cyst should consider as a differential diagnosis for masses of soft tissue.

Objective There is currently no diagnostic test for PMR. A characteristic pattern of extracapsular inflammation as assessed by contrast-enhanced MRI (ceMRI) has recently been described in the pelvis of patients with PMR. We aimed to evaluate the performance of inflammatory ceMRI signals at predefined pelvic sites as a diagnostic test for PMR. Methods Pelvic MRI scans of patients with pelvic girdle pain (n = 120), including 40 patients with an expert diagnosis of PMR and 80 controls with other reasons for pelvic pain were scored by three blinded radiologists, who evaluated the degree of contrast enhancement at 19 predefined tendinous and capsular pelvic structures. Different patterns of involvement were analysed statistically. Results The frequency of bilateral peritendinitis and pericapsulitis including less common sites, such as the proximal origins of the m. rectus femoris and m. adductor longus, differed significantly between PMR cases and controls: 13.4 ± 2.7 vs 4.0 ± 2.3. A cut-off of ≥10 inflamed sites discriminated well between groups (sensitivity 95.8%, specificity 97.1%). Bilateral inflammation of the insertion of the proximal m. rectus femoris or adductor longus tendons together with ≥3 other bilaterally inflamed sites performed even better (sensitivity 100%, specificity 97.5%). Conclusion This study confirms that a distinctive MRI pattern of pelvic inflammation (bilateral peritendinitis and pericapsulitis and the proximal origins of the m. rectus femoris and m. adductor longus) is characteristic for PMR. The high sensitivity and specificity of the set of anatomical sites evaluated suggests their clinical usefulness as a confirmatory diagnostic test.

BACKGROUND Although the profunda artery perforator flap has gained popularity in breast reconstruction, it has not been well described for reconstruction of head and neck defects. The authors report their experience with free profunda artery perforator flaps in postoncologic head and neck reconstruction. METHODS A retrospective review of all free profunda artery perforator flaps used for head and neck reconstruction from 2016 to 2019 was performed. RESULTS Overall, 61 profunda artery perforator flap reconstructions were performed: 45 single independent flaps, 12 in conjunction with a second free flap, and four in combination with two other free flaps. The profunda artery perforator flaps were most commonly used for reconstruction of the tongue (n = 19), cheek (n = 11), parotid (n = 10), and maxilla (n = 6). The profunda artery perforator flaps averaged 7.1 × 12.1 × 1.9 cm, with a mean pedicle length of 11.5 cm. The A, B, and C perforators were located at mean distances of 7.4 cm (range, 4 to 11.5 cm), 11.7 cm (range, 8 to 18 cm), and 16.1 cm (range, 14 to 20.5 cm) from the pubic tubercle along the axis of the adductor longus muscle and 7.9 cm (range, 7 to 11cm), 7.6 cm (range, 7 to 15.5 cm), and 7.2 cm (range, 6 to 16 cm) posterior and perpendicular to the axis. There were three partial flap losses. Eight patients (13 percent) had recipient-site complications necessitating operative intervention: four for vascular compromise of the profunda artery perforator flap, two for hematoma evacuation, and two for infection. Donor-site complications were noted in seven patients (11 percent), two of whom required operative intervention. CONCLUSIONS The profunda artery perforator flap is a versatile and reliable flap with consistent anatomy and a low complication rate. The profunda artery perforator flap seems to be a reasonable alternative for reconstruction of head and neck defects. CLINICAL QUESTION/LEVEL OF EVIDENCE Therapeutic, IV.

The anatomy of gracilis muscle flap pedicle and its dissection technique are well described in the literature, although dissecting its most proximal portion is technically challenging, because of the deep location and the tension in the adductor muscles posed by the harvesting position. Some modifications have been described to facilitate proximal pedicle dissection, mainly combining approaches below and above the adductor longus muscle. Throughout his experience in several hundreds of gracilis free functioning muscle transfers, the senior author has found one maneuver particularly useful in deep pedicle dissection with minimal or no need for assistance.

The aim of this study was to clarify the major differences in the electromyographic (EMG) activities in the hip joint required to achieve a non-rotational (NR) shot as compared with an instep kick from the spatiotemporal data. For this purpose, simulated EMG activities obtained from NR shots and instep kicks were analyzed using principal component analysis (PCA). The PCA was conducted using an input matrix constructed from the time-normalized average and the standard deviation of the EMG activities (101 data x (15 muscles; iliacus, gluteus maximus, rectus femoris, biceos femoris, vastus lateralis, vastus medialis, vastus intermedius, semimembranosus, semitendinosus, sartorius, tensor fasciae latae muscle, adductor magnus muscle, adductor longus muscle, gasctrocnemius, and tibialis anterior)). The PCA revealed that the 3rd, 4th and 8th principal component vectors (PCVs) of the 10 generated PCVs were related to achieving the NR shot (p < 0.05).

Hip adduction is accomplished through coordinated effort of the adductor magnus, brevis, and longus and the obturator externus and pectineus muscles. Each of these muscles may be injured at its proximal or distal insertion or in its midsubstance. The incidence of injuries to the adductor complex is difficult to determine in sport because of players' underreporting and playing through minor strains. The most commonly injured adductor muscle is the adductor longus muscle. The injury most frequently occurs at the proximal or distal musculotendinous junction, but several case reports of origin and insertional ruptures of the adductor longus exist in the literature. Successful outcomes have been obtained with both operative and nonoperative approaches in these cases. Reports of isolated proximal avulsion of the adductor magnus are less common. This article describes our surgical technique for management of a rare acute proximal adductor magnus avulsion.

A young man presented with a suspected hematocele. On exploration of the scrotum, the pathology was identified as a ruptured proximal end of the adductor longus muscle. Muscle rupture occurred as a result of the abduction of the thigh during rehabilitation exercise. This report describes the anatomy, pathophysiology, and treatment of this case.

Objective: To find the presence of trigger point in iliopsoas, adductor longus and rectus abdominis muscle and association between trigger point in these muscles and groin pain Study design: Case control study Method: A case control study was done on 60 football players (30 symptomatic with mean age 23.30 and 30 asymptomatic with mean age 21.76). All the participants were assessed for trigger points in rectus abdominis, iliopsoas and adductor longus muscles with manual palpation technique to check the pain response. Presence of myofascial trigger point were determined according to Simons and Gervin criteria. Results: Phi value for adductor longus muscle (0.484) and iliopsoas muscle (0.304) have shown association between trigger point and groin pain and were statistically significant (p

Free functional muscle transfer for brachial plexus injury is one of the alternatives to repair the upper extremity function, where usually one type of muscle is used, the gracillis. The method of using two donor muscles to restore the motor function is worth considering for a better improvement of the quality. A 36 years old man with a complete left brachial plexus injury from C5-T1 due to motorcycle accident. A double free functional muscle transfer was performed using the gracillis muscle and the adductor longus muscle with the arterial source from the thoraco-acromial artery with the phrenic and accessory nerves. The gracillis muscle is used to flex the fingers while the adductor is used for flexing the elbow. A one year post-operative evaluation showed the patient was already capable of flexing his elbow with the muscle score of 3 and also the fingers with the muscle score of 1. The double free functional muscle transfer procedure is effective in achieving the moving function of both the elbow and the hand.

Introduction/Background Inguinal lymphadenectomy is necessary when FIGO stage IB or higher. However, conventional inguinal lymphadenectomy has a high morbidity. Video endoscopic inguinal lymphadenectomy(VEIL) is emerging as a minimally invasive treatment to reduce postoperative complications. We report the case of the first VEIL using 3D scope performed in a patient with early stage vulvar carcinoma. Methodology 62 years-old woman visited for right vulvar area pain. The excisional biopsy was done and pathologic diagnosis was squamous cell carcinoma. Preop imaging study revealed Ill-defined hypermetabolic activity in right inguinal area on PET-CT and a 1.2 cm hypointense lymph node in right inguinal area on MRI(T2WI). Modified right radical hemivulvectomy, coverage with V-Y advancement flap, right inguinal lymphadenectomy, Video-endoscopic guided left inguinal lymphadenectomy was planned. VEIL was not available on right side due to flap surgery. Surface marking for femoral triangle was made on the skin. Three ports were used. Balloon trocar was used for avoid leakage of carbon dioxide gas. The main landmarks of dissection were medially the adductor longus muscle, laterally the sartorius muscle, superiorly the inguinal ligament and the inferior margin was the apex of the femoral triangle. After identified the saphenous vein, we preserved it to reduce the risk of lymphedema. Several lymph nodes were obtained. At the end of the surgery, a drain was inserted through the port. Results The total operation time was 335 minutes and left VEIL took 54 minutes. The total number of nodes removed was 8. The pathologic diagnosis was invasive squamous cell carcinoma. moderately differentiated(stage IB). There is no metastasis on any lymph node. Drain was removed on the 15th postoperative day. Hospital stay after operation was 18 days. No postoperative complication was noted. Conclusion Use of 3D scope in VEIL may provide a less invasive approach and aid surgeons by enhancing vision enabling saphenous vein-sparing technique. Disclosure Nothing to disclose

Introduction/Background For all vulvar cancer patients with tumour diameter greater than 2 cm and more than 1 mm of stromal invasion, inguinofemoral lymphadenectomy is indicated. In this video we present inguinofemoral lymphadenectomy technique with a patient with vulvar squamous cell cancer. Methodology A linear incision made 1 cm above and parallel to the groin crease starting 3 cm distal and medial to the anterior superior iliac spine and ending below the superficial inguinal ring. The borders of the operation are sartorius muscle laterally, adductor longus muscle medially and inguinal ligament superiorly. The inguinofemoral lymph nodes are divided into superficial and deep. The superficial lymph nodes are above the fascia lata and the deep nodes lye below the fascia lata and within the femoral sheath. To remove the superficial nodes, incision is carried through the subcutaneous tissues to the Camper’s fascia. The dissection should not be too close to the skin flaps as flap necrosis may develop. The fascia is incised and grasped with forceps for traction, and the fatty tissue between it and the fascia lata is removed. Usually the dissection is carried from lateral to medial and superior to inferior. Care should be taken to identify and preserve the great saphenous vein, which is superficial to the fascia of the medial thigh. To access the deep nodes, an incision is made through the cribriform fascia. Lymph nodes are always situated medial to the femoral vein in the opening of fossa ovalis. The proximal deep femoral node (node of Cloquet) is removed from the femoral triangle. The incision is closed in layers. Results not applicable Conclusion not applicable Disclosure Nothing to disclose

Background The profunda artery perforator (PAP) flap has recently been widely used for head and neck as well as breast reconstruction. Although this flap has various advantages, its vascular pedicle is relatively smaller and shorter than that of other workhorse flaps such as the anterolateral thigh flap. The posterior accessory saphenous vein (pASV) is a branch of the great saphenous vein, which runs in the posteromedial aspect of the thigh and can be included in the PAP flap. Here, we present the anatomical characteristics of the pASV and feasibility of its use in PAP flap transfers. Patients and methods An anatomical study of the pASV was conducted in nine lower extremities of five patients using ultrasonography. Several landmarks such as point A (the point where the pASV crosses the posterior border of the adductor longus muscle), point B (the point where the pASV merges with the great saphenous vein) and the inguinal crease, were marked. Distribution of the pASV was plotted, and several distances were measured. On the basis of the anatomical study, nine free PAP flap transfers were performed. Results In the anatomical study, the mean diameter of the pASV was 3.4 and 4.9 mm at points A and B, respectively. The mean available length of the pASV was 9.4 cm. In clinical cases, all flaps completely survived. No flap-related complication was observed. The pASV was included in the PAP flap in eight cases. The mean length of the harvested pASV was 8.6 cm, and the mean diameter was 3.3 mm. Indocyanine green angiography showed effective drainage using the pASV alone. Conclusions The use of the pASV can be an effective option, particularly for head and neck reconstruction, and its application in various types of reconstructive surgery can be widened.

Only a few cases of adductor longus tendon ruptures have been reported in the literature and - there are no clear criteria for conservative or surgical treatment. A case of traumatic rupture of the right distal adductor longus tendon is presented in an elite soccer player, which was surgically repaired. The condition was managed conservatively primarily. However, after 2 months, a palpable mass remained on the medial side of the thigh, and the patient had pain after moderate everyday load and insufficient strength of the right leg during physical exercise. It was decided to explore ruptured tendon surgically and reattach to the femur. Full function of the right leg was achieved at 3 months after surgical repair. At 6 months postoperatively, the patient had returned to soccer at the same level.

Introduction The present study was to study the relationship of medial hip portals with important neurovascular structures present in this region and to investigate safety zone for medial compartment. Materials and methods Thirty specimens from 15 adult cadavers were suitably positioned and anteromedial (AMP), posteromedial portal (PMP) and distal posteromedial (DMP) portals were marked and inserted along the anterior and posterior borders of adductor longus and then dissections were done. The distances were measured from point of entry of portal to femoral bundle, obturator nerve, saphenofemoral junction and profunda femoris artery. The depths of the above given structures were noted from the level of the respective portals. The transverse and sagittal angles of portal insertions were measured. Results In our study AMP and DMP were in greater proximity to the profunda femoris artery (2.5 cm and 2.8 cm, respectively), whereas obturator nerve was the closest structure in PMP (2.6 cm). Depth wise the nearest structure in all the portals was obturator nerve (1.1–1.3 cm). The mean values of transverse angle for AMP, PMP and DMP were17°, 18° and 15°, respectively, whereas the sagittal angle were 16°, 18° and 15°, respectively. Profunda femoris artery and obturator nerve were present on an average distance of 2.5 cm from the portal entry point, and depth wise these structures lie about 1 cm from the portal level. Discussion These structures are at the risk of getting damaged with misdirected portal. Thus the knowledge of angles of portal insertion is critical for avoiding iatrogenic damage.

Reconstruction of the perineum is required following oncological resections. Plastic surgical techniques can be used to restore the aesthetics and function of the perineum. The gracilis myocutaneous flap provides a substantial skin paddle, with minimal donor site morbidity. The flap is pedicled on a perforator from the medial circumflex femoral artery, giving it limited reach across the perineum. Tunnelling the flap under the adductor longus muscle may free up more of the arterial pedicle, increasing its reach. On three female cadavers, bilateral gracilis flaps were raised in the standard surgical manner, giving six flaps in total. With the flaps pedicled across the perineum, the distance from the tip of each flap was measured to the anterior superior iliac spine (ASIS). The flaps were then tunnelled under the adductor longus muscle. The distances to the ASIS were measured again. The average pedicle length was greater than 7 cm. Tunnelling the flap under the adductor longus muscle increased the reach by more than 4 cm on average. Cadaveric dissection has shown that tunnelling of the flap in a novel way increase its reach across the perineum. This additional flexibility improves its use clinically and is of benefit to plastic surgeons operating in perineal reconstruction.

Objective To describe a new ultrasound marker of the Great Saphenous Vein at the groin. Method An ultrasound marker of the Great Saphenous Vein was identified as follows: the Great Saphenous Vein was tracked in cross-sectionally starting from the Sapheno Femoral Junction and optimally visualized where it crosses the Adductor Longus muscle, i.e., 3–5 cm below the junction. This marker, corresponding to a very superficial position of Great Saphenous Vein, was named “E Point,” where E means easy to find. The search for the E point was performed on 230 limbs of 126 subjects with or without chronic venous insufficiency (training population) and the method was validated in 58 subjects (testing population). Results The E point was successfully recorded in 128/144 (89%) pathologic and in 85/86 (99%) healthy limbs. Being free from other structures, at the E point the Great Saphenous Vein was always easily calibrated. In 17 cases, the E point could not be identified due to an hypoplasic Great Saphenous Vein; in such instances, the Anterior Accessory Saphenous Vein was well evident and substituted for the Great Saphenous Vein as the main draining vein at the groin. Conclusion The E point identifies the Great Saphenous Vein in healthy and varicose patients. Failure to identify the E point indicates Anterior Accessory Saphenous Vein dominance over a hypoplasic Great Saphenous Vein.

This study examined the effect of hip flexion angle on the stiffness of the adductor longus (AL) muscle during isometric hip flexion. Seventeen men were recruited. Ten participants performed submaximal voluntary contraction at 0%, 25%, 50%, and 75% of maximal voluntary contraction (MVC) during isometric hip flexion after performing MVC at 0°, 40°, and 80° of hip flexion. Seven participants performed submaximal voluntary tasks during isometric hip extension in addition to hip flexion task. The shear modulus of the AL muscle was used as the index of muscle stiffness, and was measured using ultrasound shear-wave elastography during the tasks at each contraction intensity for each hip flexion angle. During hip flexion, the shear modulus of the AL muscle was higher at 0° than at 40° and 80° of hip flexion at each contraction intensity (p 0.016). Conversely, a significant effect was not found among hip flexion angle during hip extension at 75% of MVC (p = 0.867). These results suggest that mechanical stress of the AL muscle may be higher at 0° of hip flexion during isometric hip flexion.

A 20-year-old male collegiate soccer goalkeeper presented to an athletic trainer during the season complaining of right (dominant kicking leg) groin pain. The athletic trainer identified a mass and hematoma and suspected myositis ossificans. The patient was referred to the team physician, who ordered radiographs and magnetic resonance imaging to confirm the diagnosis and rule out other injuries. Imaging demonstrated an adductor longus muscle strain with myositis ossificans. J Orthop Sports Phys Ther 2020;50(10):586. doi:10.2519/jospt.2020.9573.

Strains of the adductor muscle are common among athletes, but avulsion at its insertion is rare. Likewise, the diagnosis and management of distal ruptures of the adductors are infrequently reported in the literature. Presented here are the common presenting clinical findings of chronic distal adductor longus tendon ruptures and a description of how these can be successfully treated with a previously undescribed surgical technique. Preoperative and postoperative magnetic resonance imaging can be compared for verification of successful surgical repair. Also reviewed are common sports and mechanisms that elicit this injury pattern, adductor longus muscle function, relevant surgical anatomy, and treatment strategies.

Cerebral palsy (CP) is the result of a static brain lesion which causes spasticity and muscle contracture. The source of the increased passive stiffness in patients is not understood and while whole muscle down to single muscle fibres have been investigated, the smallest functional unit of muscle (the sarcomere) has not been. Muscle biopsies (adductor longus and gracilis) from pediatric patients were obtained (CP n = 9 and control n = 2) and analyzed for mechanical stiffness, in-vivo sarcomere length and titin isoforms. Adductor longus muscle was the focus of this study and the results for sarcomere length showed a significant increase in length for CP (3.6 µm) compared to controls (2.6 µm). Passive stress at the same sarcomere length for CP compared to control was significantly lower in CP and the elastic modulus for the physiological range of muscle was lower in CP compared to control (98.2 kPa and 166.1 kPa, respectively). Our results show that CP muscle at its most reduced level (the myofibril) is more compliant compared to normal, which is completely opposite to what is observed at higher structural levels (single fibres, muscle fibre bundles and whole muscle). It is noteworthy that at the in vivo sarcomere length in CP, the passive forces are greater than normal, purely as a functional of these more compliant sarcomeres operating at long lengths. Titin isoforms were not different between CP and non-CP adductor longus but titin:nebulin was reduced in CP muscle, which may be due to titin loss or an over-expression of nebulin in CP muscles.

Background: The close anatomic and functional relationship between the proximal parts of the adductor longus and pectineus muscles produce considerable overlap in symptoms and signs in the inguinal region. To our knowledge, there have been no publications of ultrasound (US)-guided injection techniques into the 2 muscles. Objective: This study sought to describe US-guided injection techniques in the proximal part of the adductor longus and pectineus muscles and to validate whether these techniques deliver injections appropriately to their target muscles in unembalmed cadavers. Study Design: Cadaveric study. Methods: A preliminary trial with 2 unembalmed cadavers provided information on the target sonographic structures of proximal adductor longus and pectineus muscles. Bilateral US-guided intramuscular injections in the proximal adductor longus and pectineus were performed using the remaining 5 unembalmed male cadavers. To avoid confusion of dye location, we did not inject into both the adductor longus and pectineus muscle in the same side. After injections, each specimen was dissected to evaluate the accuracy of injection. Results: Ten injections (5 for the adductor longus muscle and 5 for the pectineus muscle) were performed targeting the proximal parts of muscles in 5 cadaveric specimens. All injections were successful and blue dye was injected accurately at the target area within the adductor longus and the pectineus muscles. No other muscles were injected unintentionally. There were no accidental penetrations and/or injuries at adjacent neurovascular structures as well. Limitation: Despite successful injection of the proximal parts of adductor longus and pectineus, this study did not verify the usefulness of this technique in clinical practice. Conclusions: The results of this study may play a role in the diagnosis and management of patients presenting with chronic pelvic pain syndrome and sports hernia. Key words: Inguinal, injections, ultrasonography, pain, cadaver, pectineus, adductor, pelvis

An adductor longus muscle rupture is a rare injury. This case report describes a 32-year-old patient with an adductor longus rupture. The trauma mechanism was a hyperabduction movement during a soccer game. Nonoperative treatment was initiated. After a follow-up of 4 years, the patient was without pain but a small swelling was still visible. This report describes the anatomy, pathophysiology, and evidence-based treatment of adductor longus rupture.

The femoral triangle is defined by the sartorius muscle laterally and the adductor longus muscle medially. These two muscles meet at the apex of the femoral triangle inferiorly. The inguinal ligament defines the superior extent of the femoral triangle. In the operation of open inguinal lymphadenectomy, the fatty and lymphatic contents of the femoral triangle are cleared, commencing superiorly on the lower abdominal musculature 5–7 cm above the inguinal ligament and extending inferiorly to the apex of the femoral triangle. The major vascular contents of the femoral triangle (common femoral artery (CFA) branching into the superficial femoral artery (SFA) and the profunda femoral artery (PFA) as well as the common femoral vein (CFV) receiving the tributaries superficial femoral vein (SFV) and profunda femoral vein) are protected. However, the long saphenous vein (LSV) is removed as part of the operative specimen after ligation at the saphenofemoral junction (SFJ) and again at the inferior extent of the dissection.

Objective To prospectively study the surgical strategies and clinical efficacy of laparoendoscopic single-site (LESS) inguinal lymphadenectomy compared with conventional endoscopic inguinal lymphadenectomy for the management of inguinal nodes. Patients and Methods A total of 12 patients with squamous cell carcinoma of the penis who underwent penectomy between February and July 2013 were enrolled in the study. All 12 patients underwent bilateral inguinal lymphadenectomy (LESS inguinal lymphadenectomy in one limb and conventional endoscopic inguinal lymphadenectomy in the other) with preservation of the saphenous vein. All lymphatic tissue in the boundaries of the adductor longus muscle (medially), the sartorius muscle (laterally), 2 cm above the inguinal ligament (superiorly), the Scarpa fascia (superficially) and femoral vessels (deeply) was removed in both surgical techniques. All 24 procedures were performed by one experienced surgeon. Results All 24 procedures (12 LESS and 12 conventional endoscopic inguinal lymphadenectomies) were completed successfully without conversion to open surgery. For LESS inguinal lymphadenectomy and conventional endoscopic inguinal lymphadenectomy groups, the mean ± sd operating time was 94.6 ± 14.8 min and 90.8 ± 10.6 min, respectively (P = 0.145). No significant differences in the incidence of postoperative complications (skin-related problems, hecatomb, lower extremity oedema, lymphatic complications and overall complications) were noted between the two groups (P > 0.05). No lower extremity oedema occurred in any limbs of the two groups. No significant differences were observed in either lymph node clearance rate or detection rate of histologically positive lymph nodes (P > 0.05). The patient satisfaction rate with scar appearance and cosmetic results was significantly better in the LESS inguinal lymphadenectomy group than in the conventional endoscopic inguinal lymphadenectomy group of (75 vs 25%; P = 0.039). Conclusions This preliminary study suggests that both LESS inguinal lymphadenectomy and conventional endoscopic inguinal lymphadenectomy are safe and feasible procedures for inguinal lymphadenectomy. Preservation of the saphenous vein during LESS inguinal lymphadenectomy/conventional endoscopic inguinal lymphadenectomy can effectively reduce the incidence of postoperative lower extremity oedema. LESS inguinal lymphadenectomy seems to provide better cosmetic results than conventional endoscopic inguinal lymphadenectomy.

Orangutan pelves commonly exhibit a large, projecting tubercle in the iliopubic region, historically assumed to homologous to the pubic tubercle in humans. However, it is not clear whether this tubercle is a unique feature of Pongo, or if it is anatomically homologous with the human pubic tubercle when considered as a soft tissue attachment point. To clarify this issue, we dissected orangutan and other ape cadaveric specimens to evaluate the pelvic brim soft tissues and how they may relate to the tubercle (when present). We additionally conducted a broad osteological survey of pelvic brim morphology across 28 primate genera (n = 294 specimens) to document the presence of the tubercle in primate pelves. Cadaveric dissections revealed that the tubercle is exclusively associated with the proximal attachment of the adductor longus muscle tendon in orangutans. Our osteological survey confirms that the tubercle is both constantly present and very prominent in orangutans. We observed that the tubercle is consistently situated along the pectineal line, lateral to where the pubic tubercle in humans is found, thereby making its structural homology unlikely. The osteological survey documented the tubercle at polymorphic frequencies in all hominoid taxa, though generally less protuberant than observed in Pongo. We argue that this further excludes its possibility of homology with the pubic tubercle, and that it may therefore be more appropriately be considered an adductor longus tubercle. We discuss possible functional and phylogenetic implications for this feature.

The main objective of this study was to investigate medial hip portals and evaluate their relation with anatomic structures in a cadaveric model.Placement of 3 medial arthroscopic portals was simulated in 10 fresh human paired cadaveric hip specimens by placing Steinmann pins into the joint under fluoroscopic control. Two portals were made at the groin, 1 anterior and 1 posterior to the adductor longus muscle, and the third portal was placed posterior to the adductor longus muscle, 5 cm distal to the groin. The specimens were then dissected, and the relation of the portals to the following structures was recorded: pectineus, adductor longus, gracilis, adductor brevis, adductor magnus, iliopsoas tendon, obturator nerve, femoral nerve, femoral artery, femoral vein, and profunda femoris artery.Regarding the anteromedial portal, the closest neurovascular structure was the profunda femoris artery, which was 10.4 ± 2.7 mm (range, 6 to 14 mm) distal to the portal. Regarding the posteromedial portal, the nearest neurovascular structure was the obturator nerve, which was 6.0 ± 3.6 mm (range, 2 to 13 mm) posterior to the portal. Regarding the distal posteromedial portal, the nearest neurovascular structures were the obturator nerve, which was 4.6 ± 3.0 mm (range, 1 to 9 mm) distal to the portal, and the profunda femoris artery, which was 10.5 ± 3.9 mm (range, 6 to 17 mm) distal to the portal.The use of the medial portals did not cause any damage to the neurovascular structures evaluated. Despite this, the portals are in close relation to the obturator nerve and profunda femoris, and care should be taken.This study investigated 3 medial hip portals in a cadaveric model and also defined safety parameters for this approach. Medial hip portals may be useful to directly approach medial hip pathologies.

Purpose To report 3 patients operated on using medial hip arthroscopic portals, describe the surgical technique and clinical outcomes. Methods Three medial portals were made, the first one at the posterior edge of the adductor longus muscle (posterior medial portal), the second one at the anterior (anterior medial portal) and the third at the posterior border of the adductor longus, 5 cm distal to the inguinal crease (distal posterior medial portal). The first case was an 8-year-old boy with a lytic lesion at the posteromedial region of the femoral neck suggestive of sub-acute osteomyelitis. The second patient was a 21-year-old male with a posteromedial femoral neck nidus. The third patient was a 42-year-old male with a posteromedial femoral neck cystic lesion. Conclusions The described portals allowed successful access to posteromedial femoral neck. There were no neurovascular lesions, infection, femoral head osteonecrosis, skin retraction or functional limitation related to the portals.

Background and Objectives: The precise location of the adductor canal remains controversial among anesthesiologists. In numerous studies of the analgesic effect of the so-called adductor canal block for total knee arthroplasty, the needle insertion point has been the midpoint of the thigh, determined as the midpoint between the anterior superior iliac spine and base of patella. "Adductor canal block"may be a misnomer for an approach that is actually an injection into the femoral triangle, a "femoral triangle block." This block probably has a different analgesic effect compared with an injection into the adductor canal.We sought to determine the exact location of the adductor canal using ultrasound and relate it to the midpoint of the thigh. Methods: Twenty-two volunteers were examined using ultrasound. The proximal end of the adductor canalwas identified where the medial border of the sartorius muscle intersects the medial border of the adductor longus muscle. The distal end of the adductor canal is the adductor hiatus, which was also visualized ultrasonographically. Results: The mean distance from the anterior superior iliac spine to the midpoint of the thigh was 22.9 cm (range, 20.3-24.9 cm). The mean distance from the anterior superior iliac spine to the proximal end of the adductor canal was 27.4 cm (range, 24.0-31.4 cm). Consequently, the mean distance from the midpoint of the thigh to the proximal end of the adductor canal was 4.6 cm (range, 2.3-7.0 cm). Conclusions: In all volunteers, the midpoint of the thigh was proximal to the beginning of the adductor canal, suggesting that an injection performed at this level is in fact a femoral triangle block.

A mudança da posição do corpo sobre a bicicleta tem sido relacionada a alterações na ativação dos músculos do membro inferior. Desta forma, o objetivo do presente estudo foi comparar a ativação dos músculos "Tibialis Anterior", "Gastrocnemius Medialis", "Biceps Femoris", "Rectus Femoris", "Vastus Lateralis", "Adductor Longus" e "Gluteus Maximus" nas seguintes situações: 1) posição de referência (posição preferida); 2) posição de adução (joelhos tangenciando o quadro da bicicleta); 3) posição de abdução (joelhos afastados do quadro da bicicleta). Seis atletas com experiência competitiva em ciclismo foram avaliados por meio da eletromiografia de superfície (EMG). Todos pedalaram em suas próprias bicicletas montadas em um ciclosimulador, com carga de trabalho normalizada pelo VO2 de forma que a taxa de troca respiratória se mantivesse entre 0,8 e 1,0. A ativação muscular foi analisada por meio da comparação da média do envelope RMS e do período de ativação para cada um dos músculos, nas três posições avaliadas. Não foram observadas diferenças significativas para a média do envelope RMS e para o período de ativação dos músculos nas três posições avaliadas, à exceção do "Adductor Longus". Observou-se maior ativação (36 ± 6%) deste músculo na posição de adução comparado a posição de abdução (25 ± 11%) para um valor de significância de p = 0,02, sem diferenças em relação a posição de referência (27 ± 7%). Estes resultados sugerem que não ocorrem alterações substanciais na ativação dos principais músculos do membro inferior quando a posição dos joelhos no plano frontal é alterada e a carga de trabalho é mantida, à exceção do aumento da participação do "Adductor Longus". Cyclist's body position on the bike has been related to changes in muscle activation. Therefore, the aim of the present study was to compare the activation of Tibialis Anterior, Gastrocnemius Medialis, Biceps Femoris, Rectus Femoris, Vastus Lateralis, Adductor Longus e Gluteus Maximus muscles in three conditions: 1) reference position (preferred position); 2) adduction position (knees almost touching the bicycle frame); 3) abduction position (knees away from the bicycle frame). Six athletes with competitive experience in cycling were evaluated using surface electromyography. They pedalled using their own bicycles mounted on a wind-trainer, with a workload relative to the second ventilatory threshold. Muscle activation was defined by the mean value of the RMS envelope and by the activation period for the three evaluated positions. There were no significant differences in muscles' RMS or activation period between the three positions, except for the Adductor Longus muscle. In adduction position, this muscle was more activated (36 ± 6%), compared to the abduction position (25 ± 11%) for a significance level of p = 0.02, without significant differences for the reference position (27 ± 7%). These results indicate that there is no substantial difference in the activation of the most important muscles of the lower limb when the position of the knee is changed in the frontal plane for the same workload level, with the Adductor Longus as an exception.

Changes in the activity of hip adductor muscles with increased running speed were investigated in 4 male sprinters (personal best for 100 m: 10.58±0.26 s). The subjects were instructed to run at three different speeds (3-4 m/s, 6-8 m/s and 9- m/s). The surface electromyograms (EMGs) of 10 muscles around the hip joint were recorded, and whole-body motions were also filmed with a high-speed video camera (150 fps). Regardless of running velocity, the adductor longus (AL) showed activity concomitant with the rectus femoris when the hip joint was in extension. This suggested that the AL functioned as a hip flexor. On the other hand, the adductor magnus (AM) showed activity when the hip joint was flexed, suggesting that the AM assisted hip extensors such as the gluteus maximus. During high-speed sprinting, the AL was also activated when the hip joint was flexed. Similarly, the AM also showed activity when the hip joint was extended, corresponding to the latter half of the support phase. During the support phase, the AM may serve to stabilize the frontal plane by co-contracting with hip abductors such as the gluteus medius and tensor fasciae latae. Furthermore, the AL and AM showed increased activity while the hip was fully flexed and extended. This remarkable muscle activity around the flexion-extension reversal point during high-speed sprinting may stabilize the hip joint so that it resists dislocative force through the unique anatomical features of the hip adductor muscles, i.e. "shunt-" rather than "spurt-type" architectural characteristics.

A total thigh flap may be another treatment option that surgeons may consider when they cannot achieve a coverage of the defect using other treatment modalities in patients with extensive decubitus ulcer concurrently with complications. It has a sufficient vascular supply and is therefore advantageous in providing a sufficient thickness, thus possibly minimizing the recurrence of decubitus ulcer. We divided the thigh muscle into the anterior and posterior compartment depending on the vascular territory to the desirable shape and size without affecting the healthy tissue. Thus, we restored defect sites to the natural shape. A 56-year-old man recently sustained grade 4 decubitus ulcer of the sacral, right ischial and bilateral subscrotal regions, accompanied by femoral osteomyelitis. The patient had a spinal cord injury due to the compression fracture of the 11th and 12th thoracic vertebrae and the 1st and 2nd lumbar ones, thus presenting with paraplegia. The patient had a past history of taking surgery for decubitus ulcer of the sacral and ischial regions (Fig. 1). Fig. 1 The patient had a paraplegia on admission, and had a past history of taking surgery for decubitus ulcer of the sacral and ischial regions several times. In addition, the patient had a deep decubitus ulcer of approximately 15.0×18.0 cm in the sacral ... In the right ischium, the tunnel connected decubitus ulcer to the proximal femur. On X-ray findings, there were multiple bony lesions in the ischium. On magnetic resonance imaging (MRI) scans, there was osteomyelitis accompanied by pathologic fracture in the proximal femur. On bone scan scintigraphy, there were findings that are suggestive of increased uptake and multiple osteomyelitis of the sacrum and ischium at the sites of decubitus ulcer. A bacterial culture test identified such bacterial strains as Pseudomonas aeruginosa and Klebsiella pneumoniae. The patient refused to take lower extremity amputation, and underwent dissection of the subtrochanteric area involving the right ischium. We therefore elevated semitendinosus and biceps femoris flaps to restore the sites of decubitus ulcer. From postoperative day 3 on, the patient had wound disruption with yellowish discharge at suture margins, accompanied by gross findings of inflammatory responses in the adjacent tissue accompanied by the partial necrosis of the femur. Therefore, we performed the infection control using daily surgical dressing, AQUACEL hydrofiber Ag (Convatec, Princeton, NJ, USA) and vacuum assisted wound dressing for approximately 15 days. Before the flap procedure, we performed a 3-dimensional (3D) femoral artery computed tomography (CT) to confirm major branches of the deep femoral artery and thereby evaluated the shape and type of preoperative vessels of the descending branch and medial circumflex branch of the lateral circumflex artery [1]. In addition, we also performed colostomy to remove major risk factors of developing infections that may impair the wound healing process. We performed the systemic infection control and daily surgical dressing for approximately one month and 15 days. Through an incision over the lateral intermuscular septum along the lateral margin of the long head of the biceps, we performed subperiosteal fileting of the femoral shaft not to damage the profunda femoris vessels and then elevated a total thigh flap (Fig. 2A) [2]. Fig. 2 (A) After making an incision over the lateral intermuscular septum along the lateral margin of the long head of the biceps where there was no vascular supply, we performed subperiosteal fileting of the femoral shaft. After the ligation of the popliteal ... For the reconstruction of colostomy, we restored the extensive defects of the sacrum using the antero-lateral compartment, for which we served one of the branches of the lateral circumflex femoral artery of the femoral artery and profundus femoral artery as a pedicle. We used the tensor faciae latae muscle in restoring the lateral margin of the sacrum (Fig. 2B). In addition, we also restored the remaining defects of the sacrum by elevating flaps from such muscles as the vastus medialis, rectus femoris, vastus intermedius and vastus lateralis and thereby obtaining a sufficient amount of padding [3]. After simply folding the antero-lateral compartment and then fixed it to the superior sacral region, we tailored the postero-lateral compartment to the shape of the defect sites to cover the right ischial and both perineal defects by serving one of the branches of the medial circumflex femoral artery and the perforating branch of the profundus femoral artery as a pedicle. Then, we also tailored the sartorius muscle from the anterior compartment and the adductor longus muscle from the posterior compartment to the distal part of the upper margin of the anus, for which we pulsated arteries that are responsible for blood supply in each muscle. With the isolation of the gracilis, adductor magnus and adductor longus muscle using an electrocautery, we folded them in the dead space around the anus and thereby obtained the padding effect. Then, we restored the subscrotal margin using the biceps femoris muscle [4]. We finally adjusted the thickness of the flap using the semimembranosus and semitendinosus muscle through a partial resection of the fascia and adipose tissue except for the vascular pedicle (Fig. 3A). Fig. 3 (A) We isolated the gracilis, adductor magnus and adductor longus muscle using an electrocautery and then folded them in the dead space around the anus, thus obtaining a padding effect. After the restoration of the subscrotal margin using the biceps femoris ... On postoperative day 10, the patient developed a necrosis on the medial side of the suture site from the adjacent flap. But this was easily resolved using a resection and a split-thickness skin graft. One month later, the patient was discharged from us (Fig. 3B). In 1956, Georgiade et al. [5] first attempted to use a total thigh flap in the treatment of patients with multiple decubitus ulcer who concurrently had complications. Since then, several authors have also used it in a same series of patients. According to most of the previous reports in this series, however, it is recommended that the defect sites be restored by elevating a total thigh flap and then simply folding a muscle flap. But its applicability is limited to patients with small decubitus ulcer or those whose lesions are limited to the ipsilateral side. We assumed that it would be difficult to make a coverage of the contralateral defects without splitting bulky thigh muscles in patients with extensive lesions. We therefore split the thigh muscles based on the vascular territory and preoperatively performed a 3D CT of the femoral artery considering the possibility of anatomical variations of the major branches of the femoral artery. Thus, we could increase the arc of rotation of the flap and thereby could achieve a coverage of the defect with the elevation of the flap by splitting the thigh muscles even to the contralateral side as well as the ipsilateral one without causing tension or twisting of the thigh muscles.

Objective: To investigate the pattern of muscle activation of the individual hip adductor muscles using a standardised simulated unilateral weight-bearing task. Design: A repeated measures design. Setting: Laboratory. Participants: 20 healthy individuals (11 females, 9 males) participated in the study. Age ranged from 20 to 25 years. Main outcome measurements: Surface electromyography recordings from adductor magnus and adductor longus muscles were taken at levels representing 10-50% of body weight during a simulated weight-bearing task. Electromyography (EMG) data were normalised to maximal voluntary isometric contraction. Results: The adductor magnus was recruited at significantly higher levels than the adductor longus muscle during a simulated weight-bearing task performed across 10-50% of body weight (p < 0.01). Conclusions: Adductor magnus and adductor longus muscles are recruited to different extents during a simulated weight-bearing task. This information should be considered when selecting exercises for management and prevention of groin strains. Closed chain exercises with weight-bearing through the lower limb are more likely to recruit the adductor magnus muscle over the adductor longus muscle.

Background Strain injury to the adductor longus muscle is a common cause of groin pain in athletes and generally occurs in the proximal portion of the muscle, near its origin from the anterior aspect of the pubis. The composition and cross-sectional anatomy of this muscle's origin has not been previously described. Hypothesis We hypothesize that the adductor longus muscle origin is composed mainly of muscle fibers and that the tendon composes only a small part of the cross section at the origin of the muscle. Study Design Descriptive laboratory study. Methods We harvested 42 adductor longus muscles from 28 cadavers and measured the cross-sectional dimensions of the tendon with microcalipers. Next, we determined the relative contributions of the tendon and muscle fibers to the cross-sectional anatomy of the muscle using optical scanning. These 2 sets of measurements were obtained at 3 locations: at the muscle origin and 1.0 and 2.0 cm distal to the origin. Results The average length and width of the tendon was 11.6 and 3.7 mm, respectively, at the origin. The average cross-sectional areas of the tendon were 49.3, 27.9, and 25.7 mm2 at points 0.0, 1.0, and 2.0 cm from its origin, respectively. The origin of the adductor longus muscle was composed of 37.9% tendon and 62.1% muscle tissue. At 1.0 cm from the origin, the percentage of tendon decreased to 34%. At 2.0 cm from the origin, the tendon composed 26.7% of the cross section. Conclusion The cross-sectional area of the tendon of the adductor longus muscle is relatively small. The muscle origin is composed predominantly of direct attachment of muscle fibers. Clinical Relevance Knowledge of the cross-sectional anatomy of the adductor longus muscle at its origin may help clinicians better understand the complex nature of injuries in this area.

We present a photographic illustration of our approach to accessing and releasing the pedicle of the gracilis muscle with a view to maximizing safety and length in this key reconstructive option available to plastic surgeons. This approach requires creation of a window in the fascia on the lateral border of the adductor longus muscle, affording a direct visualization of the medial circumflex femoral artery coming off the profunda femoris. Small proximal branches can be dealt with under greater control and the pedicle released with maximal length and safety.

Human hydatid cyst is a zoonotic infection that usually attacks visceral organs. Primary soft tissue involvement is very rare, causing a diagnostic challenge. We present a rare case of primary muscular hydatidosis in the right thigh of a 43 year-old man, who presented with painless mass. Hydatid disease should be included in the differential diagnosis of muscular masses, regardless of its location, especially in endemic areas.

The aim of this proof of concept study is to describe an ultrasound (US) assisted simplified surgical procedure for pre-terminal great saphenous vein (GSV) high ligation/division avoiding groin dissection and tributary interruption, in an office setting, in association to varices phlebectomy and saphenous vein foam occlusion treatment. Inclusion criteria: primary GSV reflux due to terminal valve, vein diameter >6 mm. By ultrasonography in standing position, the point GSV passing over the adductor longus muscle (about 3 cm from the junction) is identified. This E (easy) point, relatively superficial, free from tributaries and other structures, allows an easy grasping and extraction of the GSV vein through a 3 mm stab incision provided an ultrasonography assistance. The vein is divided/ligated about 2 cm distal from the ostium, the distal stump is cannulated and foam is injected on the distal segment from the E-point incision in a retrograde fashion, varices are avulsed by phlebectomy. Twenty procedures in 18 patients (venous clinical severity score: mean 3.15 - GSV diameter: mean 7.34) were performed, all the cases without inconveniences, with a duration not exceeding 10 min in addition to the phlebectomy procedure time. No complications as hemorrhage, infection, nerve lesion, lymphatic leak or thrombosis have been registered. At one month the residual saphenous stump length was in average 2.16 cm with complete closure of GSV in all. Three patients have been controlled at 6 months showing GSV complete closure. The procedure described is a simple office US assisted method for GSV ligationdivision, leaving the 2 last cm of the saphenofemoral junction. It could be associated to most of the procedures in use with limited additional time and resources required.

Bladder cancer most commonly spreads to the lymph nodes, lungs, bones and adrenal glands. Metastasis of bladder cancer to the skeletal muscle is extremely rare, as is the case in other malignancies. We report a case of a 62-year-old male patient who presented with pain and swelling in the right lower extremity and had difficulty walking, and who was later found to have metastasis in the adductor longus muscle 3 months after the initial diagnosis of transitional cell carcinoma of the urinary bladder. The study also provides a review of the current literature.

A case of subcutaneous and intramuscular sparganosis was confirmed on surgical excision of a worm in a 60-year-old woman suffering from painful masses in the right thigh. Sonography and MRI revealed an ill-defined intramuscular lesion and multiple cystic lesions in the subcutaneous tissue. At the time of the excision, a sparganum larva was found in the adductor longus muscle. If an intramuscular mass with a serpiginous cystic tract is seen on imaging studies in an endemic area, musculoskeletal sparganosis should be included in the differential diagnosis of a soft tissue tumor. © 2008 Wiley Periodicals, Inc. J Clin Ultrasound, 2008

Sarcomere disruptions are observed in the adductor longus (AL) muscles following voluntary reloading of spaceflown and hindlimb suspension unloaded (HSU) rat, which resemble lesions in eccentrically challenged muscle. We devised and tested an eccentric contraction (ECCON) test system for the 14-day HSU rat AL. Six to 7 hours following ECCON, ALs were fixed to allow immunostaining and electron microscopy (EM). Toluidine blue-stained histology semithin sections were screened for lesion density (#/mm2). Serial semithin sections from the ECCON group were characterized for myosin immunointensity of lesions. Five myofibrillar lesion types were identified in histological semithin sections: focal contractions; wide A-bands; opaque areas; missing A-bands; and hyperstretched sarcomeres. Lesion density by type was greater for ECCON than NonECCON ALs (P< or =0.05; focal contractions and opaque regions). Lesion density (#-of-all-five-types/mm2) was significantly different (ECCON: 23.91+/-10.58 vs. NonECCON: 5.48+/-1.28, P< or =0.05; ECCON vs. SHAM: 0.00+/-0.00; P< or = 0.025). PostECCON optimal tension decreased (Poi-drop, 17.84+/-4.22%) and was correlated to lesion density (R2=0.596), but prestretch tension demonstrated the highest correlation with lesion density (R2=0.994). In lesions, the darkly staining A-band lost the normally organized thick filament alignment to differing degrees across the different lesion types. Ranking the five lesion types by a measure of lesion length deformation (hypercontracted to hyperstretched) at the light microscopy level, related to the severity of thick filament registry loss across the lesion types at the electron microscopic level. This ranking suggested that the five lesion types seen in semithin sections at the light level represented a lesion progression sequence and paralleled myosin immunostaining loss as the distorted A-band filaments spread across the hyperlengthening lesion types. Lesion ultrastructure indicated damage involved calcium homeostasis loss (focal contraction lesions) and "thick-filament-centering" failure of titin (wide A-band lesions) in the early stages of lesion development.