Segmental Anatomy of the Vastus Lateralis: Guidelines for Muscle-Sparing Flap Harvest

Vastus lateralis flap for trochanteric sarcoma reconstruction following prior main pedicle dissection: A case report

The reconstruction of trochanteric defects presents a challenge to the reconstructive surgeon. There have been a number of locoregional reconstructive options described in the literature. These include flaps based on the lateral circumflex femoral artery and its branches, such as the tensor fascia lata, vastus lateralis (VL), anterolateral thigh (ALT) flaps. The present case further complicated this challenge as the patient had multiple recurrences of a sarcoma overlying the trochanteric region, with previous surgical resections, reconstruction and radiotherapy. The present case study describes an approach to harvesting the VL flap in a patient with previously harvested ALT.

Combining antibiotic-loaded bone cement-based free vastus lateralis muscle-sparing flap with split-thickness skin grafts: A reliable strategy for reconstructing diabetic foot ulcers at non-weight-bearing areas

Diabetic foot ulcers (DFUs) present significant challenges due to their associated amputation rates, mortality, treatment complexity and excessive costs. Our earlier work introduced a wound surgical integrated treatment (WSIT) for DFUs, yielding promising outcomes. This study focuses on a specific WSIT protocol employing antibiotic-loaded bone cement (ALBC) in the first Stage, and free vastus lateralis muscle-sparing (VLMS) flaps and split-thickness skin grafts (STSGs) in the second stage to repair non-weight-bearing DFUs. From July 2021 to July 2023, seven DFU patients (aged 47-71 years) underwent this treatment. Demographic data, hospital stay and repair surgery times were collected. Histological and immunohistochemical analyses assessed angiogenesis, collagen deposition and inflammation. SF-36 questionnaire measured pre- and postoperative quality of life. Preoperative ultrasound Doppler showed that the peak blood flow velocity of the recipient area artery was significantly >30 cm/s (38.6 ± 6.8 cm/s) in all patients. Muscle flap sizes varied from 8 × 3.5 × 1 to 18 × 6 × 2 cm. The operation time of the repair surgery was 156.9 ± 15.08 minutes, and the hospital stay was 18.9 ± 3.3 days. Histological analysis proved that covering DFUs with ALBC induced membrane formation and increased collagen, neovascularization and M2 macrophages fraction while reducing M1 macrophages one. All grafts survived without amputation during a 7- to 24-month follow-up, during which SF-36 scores significantly improved. A combination of ALBC with free VLMS flaps and STSGs proved to be safe and effective for reconstructing non-weight-bearing DFUs. It rapidly controlled infection, enhanced life quality and foot function, and reduced hospitalization time. We advocate integrating this strategy into DFU treatment plans.

Soft tissue reconstruction of the trunk with pedicled perforator and musculocutaneous flaps: A single-center comparative retrospective study

BACKGROUND

Soft tissue trunk reconstruction is often challenging. Although free microvascular flaps are a feasible option in case of extensive defects involving deep structures, pedicled flaps represent a good alternative, especially if harvested and dissected with a "microsurgical" approach. The aim of this study is to evaluate the feasibility of trunk reconstruction with the use of pedicled flaps, according to the application of our reconstructive algorithm, and to compare it to other reconstructive methods.

PATIENTS AND METHODS

From January 2017 to December 2021, we retrospectively analyzed patients who underwent soft tissue reconstruction of the trunk with pedicled flaps at the authors' institution. Patient's demographic, clinical and surgical characteristics and postoperative complications were recorded and analyzed by descriptive statistics. A comparative analysis was made between the study group and two other groups who underwent reconstruction of trunk defects with free flaps and skin grafts, respectively, at the authors' institution.

RESULTS

Forty-seven patients were included in the study. Patients' age ranged between 36 and 82 years (mean: 57.8 years). Twenty-eight patients were male, while 19 patients were female. In 76.6% of patients (36 out of 47), reconstructive procedures were performed to repair defects resulting from cancer resection. Reconstruction of superficial defects was always achieved with perforator flaps (n = 25). In case of full-thickness defects, reconstruction was carried out with musculocutaneous flaps (n = 22); latissimus dorsi and vastus lateralis were the most used flaps for chest and abdominal wall reconstruction, respectively. In our series, we observed only one case of total flap loss requiring re-operation under general anesthesia. Minor complications occurred in 8.5% of cases (4 out of 47 patients). We observed two cases of partial flap necrosis and two cases of wound dehiscence. In the skin grafts group (n = 53), the mean age was 54.5 years (range 39-85) and 56% of patients were male (n = 30). In 66% of cases (n = 30) the defect resulted from oncological resection. The overall complication rate was 18.8% (n = 10). In the free flaps group (n = 10), the mean age was 49.0 years (range 29-77) and 60% of patients (n = 6) were male. In 70% of cases (n = 7) the defect was caused by oncological resection. Complications occurred in two patients (20%). No statistically significant differences were found in terms of overall complication rate between the study group and the two comparative groups (p = .48). A significant correlation was found between the reconstructive method and the type and size of the defect, with reconstruction through free flaps being associated with larger (344.0 vs. 220.4 cm2 ) (p = .04) and full-thickness defects (80.0% vs. 46.8%) (p < .01) if compared to pedicled flaps.

CONCLUSIONS

In the new era of microsurgery, pedicled flaps represent a valid alternative to free flaps for the majority of soft tissue defects of the trunk. In our series, no statistically significant differences in terms of complications were found between reconstructions of similar defects achieved with pedicled and free flaps, and free flap use was limited to extensive full-thickness defects. In addition, the rate of postoperative complications with pedicled flaps found in our cohort was lower than the rate reported in the literature.

Dynamometric outcomes of the donor site leg after vastus lateralis free flap harvest

The vastus lateralis muscle is one of the four muscles that make up the quadriceps femoris muscle, and it is also the largest of them. Some studies have shown that patients experience lower quality of life and muscle weakness after surgical treatment of thigh muscles in order to perform reconstructive surgery of the head and neck. The aim of our study was to assess the quantitative and qualitative function of the lower extremities using an isokinetic dynamometer and a validated questionnaire on subjective difficulties in patients who underwent reconstructive surgery with the vastus lateralis free flap. Fourteen participants aged 20-70 years who suffered from malignant tumor in the head and neck region. The free vastus lateralis flap was used for reconstruction. All patients underwent isokinetic dynamometric measurement with the isokinetic dynamometer to test the isokinetic functions of the thigh muscles after surgery. In addition, subjective assessment of the lower extremities was performed using the validated questionnaire Lower Extremity Functional Scale. All isometric dynamometer measurements of the donor leg were compared with those of the unoperated leg. Peak torque and average power were significantly lower in the operated leg compared with the unoperated leg after 60°/s extension (p = 0.018 for peak torque, p = 0.021 for average power) and 180°/s extension (p = 0.019 for peak torque, p = 0.015 for average power). On the other hand, there was no statistically significant difference in dynamometer measurements after 60°/s flexion (p = 0.700 for peak torque, p = 0.854 for average power, and 180°/s flexion (p = 0.634 for peak torque, p = 0.571 for average power). The median value for the LEFS was 65.5 (40.00-71.25). The results of this study showed that there is a significant deterioration regarding the biophysical properties of the operated leg after harvesting vastus lateralis free flap.

Tolerable degree of muscle sacrifice when harvesting a vastus lateralis or myocutaneous anterolateral thigh flap

The myocutaneous anterolateral thigh (ALT) and vastus lateralis (VL) flaps include a large muscle mass and a sufficient vascular pedicle, and they have been used for decades to reconstruct traumatic and acquired defects of the head and neck and extremities. In spite of these benefits, musculoskeletal dysfunction was reported in nearly 1 out of 20 patients at follow-up. It is unclear whether the recently proposed muscle-sparing flap-raising approach could preserve VL muscle function and whether patients at increased risk could benefit from such an approach. Therefore, we performed a predictive dynamic gait simulation based on a biological motion model with gradual weakening of the VL during a self-selected and fast walking speed to determine the compensable degree of VL muscle reduction. Muscle force, joint angle, and joint moment were measured. Our study showed that VL muscle reduction could be compensated up to a certain degree, which could explain the observed incidence of musculoskeletal dysfunction. In elderly or fragile patients, the VL muscle should not be reduced by 50% or more, which could be achieved by muscle-sparing flap-raising of the superficial partition only. In young or athletic patients, a VL muscle reduction of 10%, which corresponds to a muscle cuff, has no relevant effect. Yet, a reduction of more than 30% leads to relevant weakening of the quadriceps. Therefore, in this patient population with the need for a large portion of muscle, alternative flaps should be considered. This study can serve as the first basis for further investigations of human locomotion after flap-raising.

Adipose Tissue Transfer in Dynamic Definition Liposculpture Part II. The Lower Limb: Gastrocnemius, Vastus Medialis, Vastus Lateralis, and Rectus Femoris Muscles

One big challenge of body contouring surgery is the liposculpture of the lower limbs, probably because of the imperative symmetry and the risk of contour irregularities. We are reporting our experience in fat grafting of the thighs and calves for men and women undergoing dynamic definition liposculpture.

Methods

We did cadaveric dissections of the vastus lateralis, vastus medialis, rectus femoris, and gastrocnemius muscles and identified each of their primary pedicles. We also performed fat grafting of these muscles in the contralateral virgin cadaveric specimen. We searched our records for patients who underwent fat grafting of the lower extremity in addition to dynamic definition liposculpture, from January 2016 to May 2022 at a single center in Bogotá, Colombia.

Results

Seventy-three consecutive patients met the inclusion criteria (26 men and 47 women). We grafted 102 gastrocnemius muscles, 86 vastus medialis muscles, 98 vastus lateralis muscles, and 22 rectus femoris muscles. Mean age was 34 and 41 years for men and women, respectively. Range of the fat graft volume was 50-200 mL. No complications were recorded related to fat grafting. Almost all patients were satisfied with the procedure (89%). Follow-up period ranged from 2 to 36 months.

Conclusions

Fat grafting of the lower limb muscles should be considered an alternative operative technique to enhance volume and athletic appearance of this body segment. Based on cadaveric dissections and clinical evidence, our technique is considered reliable and reproducible with remarkable outcomes and a very low complication rate.

The relationship between additional heads of the quadriceps femoris, the vasti muscles, and the patellar ligament

INTRODUCTION

The quadriceps femoris consists of four muscles: the rectus femoris, vastus medialis, vastus intermedius, and vastus lateralis. However, the effect of additional quadriceps femoris heads on the vasti muscles and patellar ligaments is unknown. The aims of the present study are to determine the relationship between additional quadriceps femoris heads and the vasti muscles and patellar ligaments and to review the morphology of the vastus lateralis, vastus medialis, and vastus intermedius.

MATERIALS AND METHODS

One hundred and six lower limbs (34 male and 19 female cadavers) fixed in 10% formalin were examined.

RESULTS

On all lower extremities, the vastus lateralis consisted of superficial, intermediate, and deep layers. The vastus medialis, on the other hand, consisted of only the longus and obliquus layers. The quadriceps head had one or more supplementary heads in 106 dissected limbs from 68 cadavers (64.1%). The distal portion of the patella was wider in lower limbs without supplementary heads than in type IA but narrower than in type IIIA. In general, the distal portion of the patella was narrower in specimens with a supplementary head than in those without (19.03 SD 3.18 mm vs. 20.58 SD 2.95 mm, p = 0.03817). Other patellar ligament dimensions did not differ significantly.

CONCLUSION

The quadriceps femoris muscle is characterized by high morphological variability. Occurrence of extra heads is at the level of 64.1%. The vastus lateralis consists of three parts (superficial, intermediate, and deep), and vastus medialis consists of two (longus and oblique).

Individually Tailored Approach to Reconstruction of Complex Defects Using Versatility of the Lateral Circumflex Femoral Artery System-Based Pedicled Flaps

Lateral circumflex femoral artery (LCFA) system is one of the most versatile donor sites in the body. We present our experience with pedicled flaps from the LCFA system, including different components for a wide variety of etiologies and locations. Twenty-three consecutive pedicled flaps were performed on 22 patients (10 females and 12 males; age 4-71 years) between 2007 and 2015 by a single surgeon. Flap size, type, and composition were tailored according to the requirements of the defects, including (1) location; (2) surface area; (3) depth; (4) number of defects; (5) presence of exposed critical structures; (6) presence of exposed foreign bodies; (7) prior use of other options; (8) history of radiation; and (9) other comorbidities. Defect locations were 10 abdominal wall (including groin and pubis), 9 ischio-gluteo-trochanteric and 4 perineal. Defect sizes ranged from 6 × 6 to 30 × 35 cm. Maximum depth of wounds ranged between 7 and 18 cm. The flap sizes ranged from 9 × 6 to 38 × 20 cm. Two flaps were fasciocutaneous perforator, 4 were myocutaneous with "muscle sparing" vastus lateralis, 10 were myocutaneous with "segmental" vastus lateralis, 5 were myocutaneous "tri-muscle," 1 was "tri-muscle," and 1 was rectus femoris only. Donor sites were closed primarily in 20 cases and with split thickness skin grafting in 3 cases. All flaps survived completely without any partial loss or congestion. Pedicled flaps from the LCFA system can be tailored individually for a wide variety of etiologies and locations. Muscles can be harvested and used as "muscle sparing," "segmental," and "tri-muscle" to accommodate the requirements of the defects.

Preliminary Functional Outcomes and Quality of Life after Tongue Reconstruction with the Vastus Lateralis Myofascial Free Flap

The aim of the present study is to report our preliminary experience with the vastus lateralis myofascial free flap (VLMFF) for tongue reconstruction according to tongue and donor site functional outcomes. Twelve consecutive patients (F: 5; median age: 54.0 years, interquartile range or IQR 42.75-69.0) were included. The validated European Organization for Research and Treatment of Cancer of the Head and Neck 35 Quality of Life Questionnaire (EORTC QLQ-H&N35) and the performance status scale for head and neck cancer (PSS-HN) questionnaires were used to assess the health-related quality of life (HRQOL). The lower extremity functional scale (LEFS) was used to self-report the donor area function. All patients were successfully treated, and no VLMFF failure was detected during a median follow-up period of 10.5 months (IQR: 6.5-33.0). The HRQOL showed a median EORTC QLQ-H&N35 score of 56.0 (IQR: 50.0-72.5). The median PSS-HN score was 80.0 (IQR: 45.0-95.0), 75.0 (IQR: 62.5-100.0), 75.0 (IQR: 62.5-100.0) for "Normalcy of Diet," "Public Eating," and "Understandability of Speech," respectively. The self-reported function of the lower extremities (donor area) showed a median LEFS of 59.0 (IQR: 32.5-74.0). This study reports optimistic data regarding the functional and quality of life outcomes after tongue reconstruction using VLMFF. Prospective controlled studies are needed to demonstrate advantages and disadvantages when compared with other reconstructive techniques.

The proximal vastus lateralis flap: An anatomical and radiological study

INTRODUCTION

Soft-tissue reconstruction following acetabular or proximal femur resection for bone tumors is challenging. The vastus lateralis flap has been proposed as an advancement or rotational flap to cover soft-tissue defects for such locoregional indications. We performed an anatomical and a radiological study to assess the vascularization of the proximal vastus lateralis muscle achieved through the transverse branch of the lateral circumflex femoral artery in order to decrease the morbidity of the classical flap retrieval technique.

MATERIAL AND METHODS

Five fresh adult cadavers were dissected bilaterally. Each vastus lateralis dissection was prealably injected with contrast-media agent through the lateral circumflex artery and CT scan images was recorded. A descriptive and an analytical study were carried out.

RESULTS

The median length and width of the entire muscle were 31.2cm (Q1-Q3: 29.7-33.3) and 12.7cm (Q1-Q3: 7.0-14.9), respectively; the median surface area of the entire vastus lateralis muscle was 282cm² (Q1-Q3: 172.6-455.6) cm². The median length and width of the perfused area were 13.3cm (Q1-Q3: 12.3-16.6) and 9.4cm (Q1-Q3: 6.9-8.8) cm, respectively; the median surface of the perfused area was 89.4cm² (Q1-Q3: 67.4-110.5) cm². The mean length of the pedicle measured on the CT scan was 6.3cm (95% CI: 5.5-7.1).

CONCLUSION

The proximal vastus lateralis flap as a pedicled muscular flap supplied by the transverse branch of the lateral circumflex femoral artery is a muscular flap that can be used by reconstructive and orthopaedic surgeons to repair soft-tissue defects around the hip joint without undue damage to the functional apparatus of the knee.

The M waves of the biceps brachii have a stationary (shoulder-like) component in the first phase: implications and recommendations for M-wave analysis

OBJECTIVE

We recently documented that compound muscle action potentials (M waves) recorded over the 'pennate' vastus lateralis showed a sharp deflection (named as a shoulder) in the first phase. Here, we investigated whether such a shoulder was also present in M waves evoked in a muscle with different architecture, such as the biceps brachii, with the purpose of elucidating the electrical origin of such afeature.

APPROACH

M waves evoked by maximal single shocks to the brachial plexus were recorded in monopolar and bipolar configurations from 72 individuals using large (10 mm diameter) electrodes and from eight individuals using small (1 mm diameter) electrodes arranged in a linear array. The changes in M-wave features at different locations along the muscle fiber direction were examined.

MAIN RESULTS

The shoulder was recognizable in most (87%) monopolar M waves, whereas it was rarely observed (6%) in bipolar derivations. Recordings made along the fiber direction showed that the shoulder was a stationary (non-propagating) feature, with short duration (spiky), which had positive polarity at all locations along the fibers. The latency of the shoulder (9.5 ± 0.5 ms) was significantly shorter than the estimated time taken for the action potentials to reach the biceps tendon (12.8 ms).

SIGNIFICANCE

The shoulder must be generated by a dipole source, i.e. a source created at a fixed anatomical position, although the exact origin of this dipole is uncertain. Our results suggest that the shoulder may not be due to the end-of-fiber signals formed at the biceps brachii tendon. The shoulder is not related to any specific arrangement of muscle fibers, as it has been observed in both pennate and fusiform muscles. Being a stationary (non-propagating) component, the shoulder is not reliable for studying changes in sarcolemmal excitability, and thus should be excluded from the M-wave analysis.

The free vastus lateralis muscle flap. A smart less used flap for soft tissue reconstruction of the weight-bearing foot

BACKGROUND

The lateral circumflex femoral artery one of the most favoured donor-site for a wide array of free flaps including either cutaneous, fascial and muscle components or a combination thereof. Here, we provide evidence on the safe use of the free vastus lateralis muscle flap and its feasibility for optimal soft tissue coverage of the weight-bearing foot.

METHODS

Eighteen consecutive patients with soft tissue defects of the heel (n = 3, 16.6%) and plantar aspect of the mid- and forefoot (n = 15, 83.3%) of either post traumatic (n = 10), diabetic (n = 6) or ischemic (n = 2) etiology, received nineteen free vastus lateralis muscle free flaps covered with split-thickness skin grafts. The postoperative results in terms of wound healing, weight-bearing function, patient satisfaction were evaluated. In patients with chronic conditions (n = 8) the AOFAS (American Orthopaedic Foot and Ankle Society) scoring system was used preoperatively and 6 months postoperatively for evaluation of reconstruction outcomes.

RESULTS

All flaps survived. Their complete anatomical integration allowed regaining normal walking in all patients. In five patients, partial loss of the skin graft which either healed spontaneously or necessitated a redo skin grafting was noted. One patient developed a late flap-skin interface ulcer, which was solved by primary excision and direct closure. Compared with the preoperative values, the mean AOFAS score in the evaluated patients (n = 8) improved significantly (34.13 vs. 77.63, p < 0.001).

CONCLUSION

The skin-grafted free vastus lateralis muscle flap can safely be used as a "smart" tool for coverage of weight-bearing foot providing optimal cushioning and functional results without fearing donor-side morbidity.

Emergency Repair of Severe Limb Injuries With Free Flow-Through Chimeric Anterolateral Thigh Perforator Flap

BACKGROUND

Complex limb trauma often involves both soft tissue and vascular defects, and is challenging for surgeons. The traditional musculocutaneous flap cannot achieve a 3-dimensional wound repair. Here we report our experience with a single-stage reconstruction and revascularization performed on complex extremity injuries using a free flow-through chimeric anterolateral thigh perforator (ALTP) flap.

PATIENTS AND METHODS

Seventeen patients (16 men; aged 19-55 years) with complex soft tissue defects attended our hospital from January 2010 to November 2017. All patients underwent reconstruction based on free flow-through chimeric ALTP flap for complex injuries in their extremities. The wound size ranged from 16 × 8 to 45 × 30 cm. The injured artery was flow-through anastomosed with the descending branch of the lateral femoral circumflex artery to regain blood flow. The muscle flap was used to fill the deep dead space on the injury site. The skin and fascial flaps were used for superficial cover. The donor site defects were sutured directly in 6 patients; simultaneous skin grafts were applied in the remaining 11 patients.

RESULTS

The ALTP flaps survived in 15 patients. Failure necessitated limb amputation in 2 patients. Six patients received both skin and fasciae flaps; 11 received flaps comprising the skin, fasciae, and vastus lateralis muscle. Partial necrosis after skin grafting was observed in 11 patients, and the wounds healed either by dressing change (1 patient) or second skin graft (10 patients). All donor sites healed without complications. All patients were followed up for 5 to 60 months (mean, 21.8 months).

CONCLUSIONS

The flow-through chimeric ALTP flap can be used for 1-stage reconstruction of 3-dimensional soft tissue defects and vascular gap. It is feasible for managing complex injuries of both the upper and lower extremities in emergency settings.

Chimeric Anterolateral Thigh Flap for Primary Functional Reconstruction of Complex, Composite Near Total Hemi Facial Post Excision Defects

INTRODUCTION

Microvascular free tissue transfer has revolutionized the management of complex composite head and neck defects.

AIM

To evaluate the functional and aesthetic outcomes in the primary reconstruction of post-excisional near total hemifacial defects with the chimeric anterolateral thigh flaps (cALT).

MATERIALS AND METHODS

The author as a prelude to this clinical study has done a cadaveric study on the quadriceps artery angiosome. In this retrospective cohort study, data are collected from the records of 6 patients who had undergone primary cALT flap reconstruction for their post excisional near total hemifacial defects from January 2013 to December 2017. All 6 patients with various advanced malignancies involving the hemiface underwent wide local excision. Wide local excision resulted in the loss of skin and critical facial muscles that led to near total hemiface composite defects. Reconstructions were done with the cALT flaps that included segment of the vastus lateralis muscle harvested on its independent neurovascular perforator pedicle and the skin paddle on a separate perforator. In all cases, the facial nerve stumps were anastomosed to the nerve to vastus lateralis for reanimation of the face. In addition, 4 patients underwent primary radical neck dissection, but all had postoperative radiotherapy and chemotherapy.

RESULTS

All patients attained well-pronounced nasolabial fold, symmetrical smile, and good oral competence in an average period of 10.75 months post operatively. In an average of 22 months follow up, none of them had locoregional recurrences. None required any secondary procedures.

CONCLUSION

In the post excisional near total hemifacial composite defects, primary functional reconstruction with tailored cALT flaps can bring good aesthetic and functional results.

The fifth head of quadriceps femoris: for sure?

PURPOSE

The quadriceps femoris has been described as a muscle composed by four heads: rectus femoris, vastus lateralis, vastus medialis and vastus intermedius. Each head fuse with the other ones making up the quadriceps tendon, which inserts into the patella. Nevertheless, there has been described a fifth component of the quadriceps muscle in recent anatomical publications. Understanding this fifth head may be important for orthopedics and radiologist.

METHODS

Cadaveric dissection of left thigh of a female 83 years old was performed to demonstrate a fifth head of the quadriceps femoris muscle.

RESULTS

In this study, a fifth head of the quadriceps femoris muscle was found in the left thigh of a female cadaver 83 years old. This fifth head was made up by four independent muscular fascicles attaching in a common flat tendon that joins distally with the lateral border of the quadriceps tendon. The fifth head found was supplied by branches of the ascending branch of the lateral femoral circumflex artery and by branches of the deep lateral division of the femoral nerve.

CONCLUSIONS

The incidence of this fifth belly in cadaveric studies has been reported as a range from 29 to 100%. However, no published articles refer an anatomical finding such as this multi-bellied fifth head. The knowledge of the existence and location of the fifth belly is necessary to make accurate diagnosis of QF muscle strains. Its anatomical course may be involved in patellar tracking.

Potentiation of the first and second phases of the M wave after maximal voluntary contractions in the biceps brachii muscle

The study was undertaken to examine separately the potentiation of the first and second phases of the M wave in biceps brachii after conditioning maximal voluntary contractions (MVCs) of different durations. M waves were evoked in the biceps brachii muscle before and after isometric MVCs of 1, 3, 6, 10, 30, and 60 s. The amplitude, duration, and area of the first and second phases of monopolar M waves were measured during the 10-min period following each contraction. Our results indicated that the amplitude and area of the M-wave first phase increased after MVCs of long (≥ 30 s) duration (P < 0.05), while it decreased after MVCs of short (≤ 10 s) duration (P < 0.05). The enlargement after the long MVCs persisted for 5 min, whereas the depression after the short contractions lasted only for 15 s. The amplitude of the second phase increased immediately (1 s) after all MVCs tested (P < 0.05), regardless of their duration, and then returned rapidly (10 s) to control levels. Unexpectedly, the amplitude of the second phase decreased below control values between 15 s and 1 min after the MVCs lasting ≥ 6 s (P < 0.05). Our results reinforce the idea that the presence of fatigue is a necessary condition to induce an enlargement of the M-wave first phase and that this enlargement would be greater (and occur sooner) in muscles with a predominance of type II fibers (quadriceps and biceps brachii) compared to type-I predominant muscles (tibialis anterior). The unique findings observed for the M-wave second phase indicate that changes in this phase are highly muscle dependent. Graphical abstract Left panel-Representative examples of M waves recorded in one participant before (control) and at various times after conditioning maximal voluntary contractions (MVCs) of short (a1) and long (a2) duration. Left panel-Time course of recovery of the amplitude of the first (b1) and second (b2) phases of the M wave after conditioning MVCs of different durations.

The "nugget design": A modified segmental gracilis free flap for small-sized defect reconstruction on the lower extremity

BACKGROUND

Little attention has been given to the segmental free gracilis muscle flap supplied by secondary proximal pedicles. We introduce a technical refinement for small-sized three-dimensional defect reconstruction on the foot.

METHODS

Between November 2013 and August 2016, three patients with a mean age of 66 years (range 47-70 years) were included. A segmental gracilis free flap supplied by the most proximal secondary pedicle was harvested according to a modified "nugget design" to treat small-sized defects on the lower extremity requiring dead space reconstruction. Minor and major complications, sensitivity with Semmes-Weinstein monofilament test, soft tissue stability and patient satisfaction at final follow-up were recorded.

RESULTS

In one case, a segmental gracilis muscle was used for dorsal foot reconstruction after debridement of metatarsal phalanx I with osteomyelitis. In two cases, the segmental gracilis free muscle was harvested for defect reconstruction on the right plantar foot after excision of a melanoma. The first patient required revision after partial failure of the initial segmental gracilis free muscle flap. Overall, good results in foot function and a high degree of patient satisfaction was achieved (Likert scale 9.7, range 9-10) after a mean follow-up of 13 months (range 3-24 months).

CONCLUSIONS

Taken from the very proximal dorsal part of the gracilis muscle supplied by the most proximal secondary pedicle and leaving the vast majority of the muscle intact preserves the option to harvest a normal gracilis flap. This technique is especially suitable for small, three-dimensional defects on the lower extremity.

Chimeric anterolateral thigh free flap for reconstruction of complex cranio-orbito-facial defects after skull base cancers resection

Complex cranio-orbito-facial defects after skull base cancers resection entail a functional and esthetic reconstruction. The introduction of endoscopic assisted techniques for excision surgery with the advances in reconstructive surgery and anesthesiology allowed to improve the management of such critical patients. We report a series of chimeric anterolateral thigh (ALT) flaps used to reconstruct complex cranio-orbital-facial defects after skull base surgery. A retrospective review of patients that underwent cranio-orbito-facial reconstruction using a chimeric ALT flap from March 2013 to October 2015 at a single tertiary care referral Institute was performed. All patients were affected by locally-advanced malignant tumor and the resulting defects involved the skull base in all cases. The ALT flaps were perforator-based flaps with different components: fascia, skin and muscle. The different flap territories had independent vascular supply and were independent of any physical interconnection except where linked by a common source vessel. Ten patients were included in the study. Three patients underwent adjuvant radiotherapy and to chemotherapy. The mean hospitalization time was 21 days (range, 8-24 days). One failure was observed. After a mean follow-up of 12.4 months, 3 patients died of the disease, 2 are alive with disease, while 5 patients (50%) are currently alive without evidence of disease. Chimeric ALT flap is a reliable and versatile reconstructive option for complex cranio-orbito-facial defects resulting from skull base surgery. The chimeric flap composed of different territories proved to be adequate for a patient-tailored three-dimensional reconstruction of the defects as well as able to resist to the postoperative adjuvant treatments.

An uncommon case of sarcomatoid urothelial carcinoma in covered bladder exstrophy

We report a case of a woman affected by covered exstrophy, uterus didelphys and external genital malformation presenting with advanced bladder cancer. After neoadjuvant therapy and anterior pelvic exenteration, the abdominal wall was reconstructed with a pedicled myocutaneous muscle-sparing vastus lateralis flap.

Variability and reliability of the vastus lateralis muscle anatomy

PURPOSE

The aims of this study are to investigate the variability of the morphological and neurovascular anatomy of the vastus lateralis (VL) muscle and to describe the relationships among its intramuscular partitions and with the other muscles of the quadriceps femoris. Clinical implications in its reliability as a flap donor are also discussed.

METHODS

In 2012, the extra- and intramuscular neurovascular anatomy of the VL was investigated in 10 cadaveric lower limbs. In three specimens, the segmental arterial pedicles were injected with latex of different colors to point out their anastomotic connections. The morphological anatomy was investigated with regard to the mutual relationship of the three muscular partitions and the relation of the VL with the other muscles of the quadriceps femoris.

RESULTS

The VL has a segmental morphological anatomy. However, the fibers of its three partitions interconnect individually and with the other bellies of the quadriceps femoris, particularly, in several variable portions with the vastus intermedius and mainly in the posterior part of the VL. The lateral circumflex femoral artery and its branches have variable origin, but demonstrate constant segmental distribution. Intramuscular dissection and colored latex injections show a rich anastomotic vascular network among the three partitions.

CONCLUSIONS

Moderate variability exists in both the myological and the neurovascular anatomy of the VL. Despite this variability, the anatomy of the VL always has a constant segmental pattern, which makes the VL a reliable flap donor. Detailed knowledge of the VL anatomy could have useful applications in a broad clinical field.

The vastus lateralis free flap for lower extremity gustilo grade III reconstruction

BACKGROUND

Orthopedic trauma patients with Gustilo grade III injuries to the distal third of lower extremity present challenges to optimum reconstructive management. There is no consensus on the ideal autologous tissue for transfer in large lower extremity defect reconstruction. We present a large case series utilizing the vastus lateralis (VL) free flap for lower extremity Gustilo grade III reconstruction.

PATIENTS AND METHODS

This is a case series of patients who underwent VL free tissue transfer for Gustilo grade III injuries. A total of 38 free tissue transfers were performed for lower extremity reconstruction, 19 of which were VL flaps. Mean interval between injury and reconstruction was 46 days (range 7-240 days).

RESULTS

The mean wound size was 11.37 cm x 11.42 cm and all cases underwent delayed reconstruction. Seven day flap viability was 100% and 30-day flap viability was 17/19 (89%). There were six complications: two hematomas requiring drainage, one flap dehiscence, one distal flap loss requiring a reverse saphenous vein graft extension, and two complete flap losses. Of the two failed flaps, one was attributed to heparin-induced thrombocytopenia and the other to venous congestion complicated by methicillin-resistant Staphylococcus aureus infection.

CONCLUSIONS

The VL free flap is a reliable and versatile flap that can be tailored and tangentially thinned to match the shape and size of a defect, and the long pedicle allows the surgeon to stay away from the zone of injury. This flap should be strongly considered for lower extremity reconstruction, especially in salvage operations for large defects. © 2015 Wiley Periodicals, Inc. Microsurgery 37:212-217, 2017.