The distance between the fibular collateral ligament tunnel and the common peroneal nerve allows a posterolateral corner reconstruction without neurolysis.

PURPOSE: The most popular knee posterolateral corner (PLC) reconstruction techniques describe that a common peroneal nerve (CPN) neurolysis must be done to safely address the posterolateral aspect of the knee. The purpose of this study was to measure the distance between the CPN and the fibular insertion of the FCL in different degrees of knee flexion in cadaveric specimens, to identify if tunnel drilling could be done anatomically and safely without a CPN neurolysis. METHODS: Ex vivo experimental analytical study. Ten fresh frozen human knees were dissected leaving FCL and CPN in situ. Shortest distance from the centre of the FCL distal tunnel and CPN was measured (antero-posterior and proximal-distal wire-nerve distances) at 90°, 60°, 30°, and 0° of knee flexion. Measurements between different flexion angles were compared and correlation between knee flexion angle and distance was identified. RESULTS: The mean distance between the FCL tunnel and the CPN at 90° were 21.15 ± 6.74 mm posteriorly (95% CI: 16.33-25.97) and 13.01 ± 3.55 mm distally (95% CI: 10.47-15.55). The minimum values were 9.8 mm posteriorly and 8.9 mm, respectively. These distances were smaller at 0° (p ≤ 0.017). At 90° of knee flexion, the mean distance from the fibular tip to the CPN distally was 23.46 ± 4.13 mm (20.51-26.41). CONCLUSION: Anatomic localization and orientation of fibular tunnels can be done safely while avoiding nerve neurolysis. Further studies should aim to in vivo measurements and results.

Connection between medial dorsal cutaneous nerve and saphenous nerve: case report.

PURPOSE: There are no data on the connection of the saphenous nerve (SN), located on the medial side of the foot, with the terminal branches of the superficial fibular nerve. The aim of this study is to reveal the variation that surgeons should pay attention to for anesthesia applied in foot surgeries. METHODS: In this study, the left foot of a 70-year-old female cadaver fixed with formalin was dissected. The distance to the medial malleolus and the incision line was recorded using digital caliper to determine the reference points in the resulting variation. RESULTS: It was observed that a branch from the SN, which arose from the SN and proceeded anteriorly to the upper part of the medial malleolus and continued towards the dorsum of the foot, hooked with a branch from the medial dorsal cutaneous nerve (MDCN). The branches arising from this hook were distributed on the medial edge of the foot up to the proximal metatarsophalangeal joint I. The distance of this nerve connection to the medial malleolus is 91.14 mm, and the distance to the incision line is 15.76 mm. CONCLUSIONS: It is suggested that the case presented as an unusual SN variation, which may affect the success of local anesthesia in invasive procedures to the medial part of the foot and could be considered in the evaluation of sensory loss after anteromedial surgical approach to the ankle, should be included in the classification of the cutaneous innervation pattern of the foot.

The Superficial Peroneal Nerve Is at Risk during the "All Inside" Arthroscopic Broström Procedure: A Cadaveric Study.

Background: The arthroscopic Broström procedure is a promising treatment for chronic ankle instability. However, little is known regarding the location of the intermediate superficial peroneal nerve at the level of the inferior extensor retinaculum; knowledge about this location is important for procedural safety. The purpose of this cadaveric study was to clarify the anatomical relationship between the intermediate superficial peroneal nerve and the sural nerve at the level of the inferior extensor retinaculum. Methods: Eleven dissections of cadaveric lower extremities were performed. The origin of the experimental three-dimensional axis was defined as the location of the anterolateral portal during ankle arthroscopy. The distances from the standard anterolateral portal to the inferior extensor retinaculum, sural nerve, and intermediate superficial peroneal nerve were measured using an electronic digital caliper. The location of inferior extensor retinaculum, the tract of sural nerve, and intermediate superficial peroneal nerve were checked using average and standard deviations. For the statistical analyses, data are presented as average ± standard deviation, and then they are reported as means and standard deviations. Fisher's exact test was used to identify statistically significant differences. Results: At the level of the inferior extensor retinaculum, the mean distances from the anterolateral portal to the proximal and distal intermediate superficial peroneal nerve were 15.9 ± 4.1 (range, 11.3-23.0) mm and 30.1 ± 5.5 (range, 20.8-37.9) mm, respectively. The mean distances from the anterolateral portal to the proximal and distal sural nerve were 47.6 ± 5.7 (range, 37.4-57.2) mm and 47.2 ± 4.1 (range, 41.0-51.8) mm), respectively. Conclusions: During the arthroscopic Broström procedure, the intermediate superficial peroneal nerve may be damaged by the anterolateral portal; the proximal and distal parts of the intermediate superficial peroneal nerve were located within 15.9 and 30.1 mm, respectively, at the level of the inferior extensor retinaculum in cadavers. These areas should be considered danger zones during the arthroscopic Broström procedure.

A unique variation of the deep fibular nerve: A case report.

Deep fibular nerve is one of the two terminal branches of the common fibular nerve. The deep fibular nerve can be damaged in procedures related the anterior compartment of the leg such as the application of an external fixator to the leg and operations using intramedullary nailing after tibial fracture. Therefore, it is important to know the anatomy and variations of the deep fibular nerve. An anatomical variation concerning the deep fibular nerve was detected in the right lower extremity of the 65-year-old cadaver we dissected. In this case, it was observed that the deep fibular nerve split into two nerve arms in the distal half of the leg and reunited after continuing 9cm apart to form a loop. This loop formation may increase the iatrogenic damage of the deep fibular nerve as a result of surgery and percutaneous interventions to the anterior leg compartment. We described in this case report a hitherto unobserved finding of the branching pattern of the deep fibular nerve. We think that this unique anatomical variation seen in the right lower extremity of the case of academic interest and will also help orthopedicians in anterior leg compartment surgery.

An overview of common peroneal nerve dysfunction and systematic assessment of its relation to falls.

PURPOSE: Compression of the peroneal nerve is recognized as a common cause of falls. The superficial course of the peroneal nerve exposes it to trauma and pressure from common activities such as crossing of legs. The nerve can be exposed also to distress due to metabolic problems such as diabetes. The purpose of our manuscript is to review common peroneal nerve dysfunction symptoms and treatment as well as provide a systematic assessment of its relation to falls. METHODS: We pooled the existing literature from PubMed and included studies (n = 342) assessing peroneal nerve damage that is related in any way to falls. We excluded any studies reporting non-original data, case reports and non-English studies. RESULTS: The final systematic assessment included 4 articles. Each population studied had a non-negligible incidence of peroneal neuropathy. Peroneal pathology was found to be consistently associated with falls. CONCLUSION: The peroneal nerve is an important nerve whose dysfunction can result in falls. This article reviews the anatomy and care of the peroneal nerve. The literature review highlights the strong association of this nerve's pathology with falls.

Nerve branches to the anterior tibial artery: Clinical application.

Arteries receive vascular branches (VBs) from peripheral nerves. VBs are thought to be involved in arterial constriction. Although the anterior tibial artery (ATA) receives VBs, information on their branching patterns and distribution areas remains limited. The aim of this study was to investigate the anatomical structures of the VBs reaching the ATA. Forty cadaver limbs were examined to assess the branching patterns and distribution areas of the VBs reaching the ATA. The VBs reaching the ATA ramified from the deep fibular nerve (DFN), and the ATA received two or three VBs in each limb. The following mean distances from the head of fibula to the points at which the VBs reached the ATA were measured: all the VBs, 1st VB, 2nd VB and 3rd VB. The measurements were 51.5 ± 23.2 mm, 33.3 ± 3.7 mm, 53.3 ± 18.6 mm, and 72.2 ± 24.5 mm, respectively. In all limbs, the DFN and the ATA converged after the DFN branched into the 1st VB. The 2nd VB in 38 of 40 limbs and the 3rd VB in 20 of 32 limbs were distributed in the ATA proximal to the convergence point of the ATA and the DFN. These findings revealed that all VBs reaching the ATA ramified from the DFN in all limbs. The ATA received two or three VBs, and all the 1st VBs distributed to the ATA proximal to the convergence point.

Relationships of the superficial fibular nerve and sural nerve with respect to the lateral malleolus: implications for ankle surgeons.

PURPOSE: Superficial fibular nerve (SFN) and sural nerve are at risk during osteosynthesis of the lateral malleolus. The aim of this anatomical study was to describe the relationships of the superficial fibular and sural nerves with respect to the lateral malleolus. METHODS: Nine corpses (18 ankles) were dissected, using a direct lateral approach. Measurements were recorded between the fibula and the nerves, and the pattern variations of the SFN were recorded for both right and left side to assess intra-individual variability. RESULTS: Distance between the tip of the lateral malleolus and the piercing of fascia cruris was 111 ± 26 mm for type 1 pattern, and range was 46-161 mm all types included. 78% (14 SFN) were type 1 pattern, 17% (3 SFN) were type 2 pattern, and 5% (1 SFN) were type 3 pattern. 44% (4 specimen) had a type 1 pattern SFN on one ankle and another pattern on the other ankle. The sural nerve was always observed just posterior to the lateral malleolus. CONCLUSION: This study demonstrated a great inter-individual variability especially for the SFN, but also an intra-individual variability with frequent different patterns between right and left leg. It is important to know the anatomical variations of the SFN and sural nerve to decrease the risk of intra operative nerve injury during direct lateral approach of lateral malleolus.

Bifurcation of the sciatic nerve: A descriptive study on a South African cadaver cohort.

BACKGROUND: The sciatic nerve bifurcates into the tibial and common fibular nerves in six different regions: the pelvic region, gluteal region, proximal, middle, or distal third of the posterior thigh, or in the popliteal fossa. Inadequate knowledge of sciatic nerve anatomy could lead to failed nerve blocks, and damage during intramuscular injections. Limited studies have been done on African population groups and lack a quantifiable method to classify the levels of sciatic nerve bifurcation. AIM: Thus, this descriptive cadaver study aimed to assess the bifurcation level of the sciatic nerve in a South African population group using a quantifiable method. METHODS: Three hundred and thirty-eight formalin-fixed limbs from three universities were dissected between March and August 2018. Type A was classified if the sciatic nerve bifurcated within the pelvic region. A sciatic nerve bifurcation level index (SNBLI) was developed for this study to quantitatively classify the region of sciatic nerve bifurcation into types B to F. RESULTS: Type F bifurcation was most common (79.6%), and types B and C were not observed. In 15 (0.04%) specimens, two separate nerves entered the gluteal region and converged to form the sciatic nerve distal to the piriformis, which could bifurcate either in the distal third of the posterior thigh or popliteal fossa. CONCLUSION: This is the first study to provide information on the sciatic nerve bifurcation in a large South African cadaver cohort. Moreover, we created a quantifiable method that can be used to classify the sciatic nerve bifurcation level. This will be beneficial in ensuring accurate comparison between different population groups in future.

Low to moderate risk of nerve damage during peroneus longus tendon autograft harvest.

PURPOSE: This study aims to evaluate the proximity of the tendon stripper to both the peroneal and sural nerves during peroneus longus tendon (PLT) autograft harvesting. METHODS: Ten fresh-frozen human cadaveric lower extremities were used to harvest a full-thickness PLT autograft using a standard closed blunt-ended tendon stripper. The distance to the sural nerve from the PLT (at 0, 1, 2 and 3 cm proximal to lateral malleolus (LM), and the distance to the peroneal nerve and its branches from the end of the tendon stripper were measured by two separate observers using ImageJ software. RESULTS: The average distance from the PLT to the sural nerve increased significantly from 0 to 2 cm proximal to LM. The average distance to the sural nerve at the LM was 4.9 ± 1.5 mm and increased to 10.8 ± 2.4 mm (2 cm proximal to LM). The average distance from the tendon stripper to the deep peroneal nerve was 52.9 ± 11.4 mm. The average distance to the PLT branch of peroneal nerve was 29.3 ± 4.2 mm. The superficial peroneal nerve, which coursed parallel and deep to the tendon stripper, was on average 5.2 ± 0.7 mm from the end of the stripper. No transection injuries of the nerves were observed in any of the ten legs after harvesting. CONCLUSION: This cadaver study found during a full-thickness PLT harvest, the distances between the tendon stripper and the nerves were greater than 5 mm with an initial incision at 2 cm proximal to LM which is recommended.

The Intraseptal Course of the Superficial Peroneal Nerve: An Anatomic Study.

BACKGROUND: Anatomic and clinical studies show many variants of the superficial peroneal nerve (SPN) course and branching within the compartments and at the suprafascial layer. The anatomy of the transition zone from the compartment to the subcutaneous layer has been occasionally described in the literature, mainly in studies reporting the intraseptal SPN variant in 6.6% to 13.6% of patients affected by the SPN entrapment syndrome. Despite the little evidence available, the knowledge of the transition zone is relevant to avoid iatrogenic lesions to the SPN during fasciotomy, open approaches to the leg and ankle, and SPN decompression. Our anatomic study aimed to describe the SPN transition site and to evaluate the occurrence of a peroneal tunnel and of an intraseptal SPN variant. METHODS: According to the institutional ethics committee requirements, 15 fresh-frozen lower limbs were dissected to study the SPN course and its branching, focusing on the transition site to the suprafascial layer. RESULTS: The SPN was located in the anterior compartment in 2 cases and in the lateral in 13. An intraseptal tunnel was present in 10 legs (66%), at a mean distance of 10.67 cm from the lateral malleolus. Its mean length was 2.63 cm. The tunnel allowed the passage of the main SPN in 8 cases and of its branches in two. In the remaining 5 legs (33%), the SPN pierced a crural fascia window. CONCLUSION: In our sample a higher rate than expected of intraseptal SPN variants was found. CLINICAL RELEVANCE: The knowledge of the anatomy of the SPN course and intraseptal variant is relevant to avoid iatrogenic lesions during operative dissection. Further studies are needed to evaluate the effective prevalence of an intraseptal tunnel, independently from the SPN entrapment syndrome, and how to avoid associated iatrogenic complications.

Topography of muscular branches of the superficial fibular nerve based on anatomical preparation of human foetuses.

BACKGROUND: The progress of pediatric surgery and increasingly better diagnosis of fetal defects require detailed knowledge of human developmental anatomy. Precise knowledge of the anatomy of innervation of the lower extremities corresponds to this subject and is not only cognitive but also clinically important. The aim of this study was to analyse the anatomy of the topography of the muscular branches of the superficial fibular nerve (NPS) in the prenatal period, which will fill a gap in the literature. METHODS: The analysis was carried out on 207 human foetuses aged from the 113th day to 222nd day of foetal life. The study material is a part of the collection of the Division of Normal Anatomy of Wroclaw Medical University. The study incorporated the following methods: anthropological, preparational and image acquisition which was acquired with the use of high-resolution digital camera. Statistical analysis was carried out with the use of STATISTICA package. RESULTS: Based on the research results the number of muscle branches of the examined nerve was determined. It was shown that in more than half of the cases the two nerve branches are responsible for Peroneus Longus innervation and in about 90% of cases one branch is responsible for Peroneus Brevis innervation. Based on the obtained data a unique, new typology of distribution of these branches was created. It has been shown that the bipinnate type is the most common in the examined fetal population. The presence of statistically significant differences in the frequency of occurrence of individual innervation patterns depending on sex and body side were excluded (p > 0.05). There were also no statistically significant changes in the frequency of occurrence of individual types of NPS branch distribution according to fetal age (p > 0.05). CONCLUSIONS: The created unique typology of NPS branch distribution based on extensive preparation material is an important supplement to the anatomical knowledge and at the same time, due to the peripheral and superficial location of the described structures, it has a relevant clinical significance.

Anatomy of the superficial peroneal nerve: Can we predict nerve location and minimize iatrogenic lesion?

OBJECTIVE OF THE STUDY: Knowledge of anatomical variations of the superficial peroneal nerve (SPN) may minimize iatrogenic insults. The aim of the investigation was to perform an anatomical description of the SPN. MATERIALS AND METHODS: Twenty-three embalmed cadaver lower limbs were dissected. RESULTS: The SPN emerged from the crural fascia about 6.3±7.7mm anteromedial to the anterior border of the fibula and 26.8±12.6mm anteromedial and 113.6±43.9mm superior to the tip of the lateral malleolus. The median point of bifurcation into two terminal branches was 13.0mm anteromedial to the anterior border of the fibula and 34.9±14.7mm anteromedial and 81.0±69.0mm superior to the tip of the lateral malleolus. The SPN was found between 5.76% and 7.70% of the individual's height proximal to the tip of the lateral malleolus, with an unpredictable branching pattern over the intermalleolar line. CONCLUSION: A lateral ankle approach over the posterolateral surface of the fibula (posterior to the tip of the lateral malleolus) minimizes the risk of iatrogenic nerve lesion.

The anatomical relationship of the common peroneal nerve to the proximal fibula and its clinical significance when performing fibular-based posterolateral reconstructions.

PURPOSE: The common peroneal nerve (CPN) can be injured during fibular-based posterolateral reconstructions due to its close relationship to the neck of the fibula. Therefore, the purpose of this study was to observe the course of the CPN and its branches around the fibular head and neck and quantify the position in relation to relevant bony landmarks and observe the relation between tunnel drilling for posterolateral corner reconstruction and both the tunnel entry and exit at the proximal fibula and the CPN and its branches was observed. METHODS: In 101 (mean age = 70.6 ± 16 years) embalmed cadaver knees, the relationship between bony landmarks (tibial tuberosity, styloid process of fibula (APR)) and the CPN and its branches were established and 8 (M1-M8) distances from these landmarks measured; mean, SD and 95% CI were recorded. In 21 of these knees, a fibula tunnel was drilled as in PLC reconstruction and the association of the CPN and its branches to the tunnel entry and exit were judged by two independent observers. Fisher's exact test of independence was used to determine significant differences between genders. Tunnel intersection was analysed in a binary yes/no fashion and was described in frequencies and percentages. RESULTS: The mean distance from the APR to where the CPN reaches the fibula neck (M1) was 31.4 ± 8.9 mm (CI:29.8-33.0); from the apex of the styloid process (APR) to where the CPN passes posterior to the broadest point of the fibular head (M3) was 21.7 ± 12.6 mm (CI:19.4-24.0); from the apex of the APR to the most proximal point of the CPN/CPN first branch in the midline of the fibular head (M2) was 37.0 ± 6.7 mm (CI: 35.4-37.7). Out of the 21 randomly selected knees for drilling, the first branch of the CPN was damaged at the tunnel entry point in 7 (33%), and in 5 knees (24%), the CPN was damaged at the tunnel exit. In one knee, at both the tunnel entry and exit, the first branch of the CPN and the CPN were intersected, respectively. CONCLUSION: The results of this study strongly suggest that the CPN is at risk when drilling the fibula tunnel performing fibula-based posterolateral corner reconstructions. The total injury rate was 57% with a 33% incidence of injury to the first branch of the nerve at the tunnel entry and 24% to the CPN at the tunnel exit. CLINICAL RELEVANCE: Due to the high incidence of injury, percutaneous placement of guide pins and tunnel drilling is not recommended. The nerve should be visualized and protected by either a traditional open approach or minimally invasive techniques. With a minimally invasive approach, the nerve should be identified at the fibula neck and then followed ante- and retrograde.

A rare third head of the biceps femoris in the posterior thigh.

The occurrence of a third head of the biceps femoris is very rare. We encountered the case of a 90-year-old Japanese male cadaver with a third head of the biceps femoris in the posterior aspect of the thigh during dissection at Aichi Medical University in 2016. It originated from the proximal part of the femur and fused with the muscle belly between the long and short heads of the biceps femoris. Additionally, three muscle tendons were connected to the gluteus maximus. To the best of our knowledge, this is the first report on the third head of the biceps femoris demonstrating two origins, i.e., the proximal part of the femur and the insertion tendon of the gluteus maximus. Moreover, the third head, as well as the short head, of the biceps femoris was innervated by the muscular branch of the common peroneal nerve. Based on the origin and innervation, it can be believed that the third head of the biceps femoris is analogous to its short head and is related to the tenuissimus, a phylogenetic remnant. Therefore, we concluded that this third head is an intermediate muscle type of the tenuissimus and short head of the biceps femoris.

The articular branch of the peroneal nerve to the proximal tibiofibular joint descends at a mean height of approximately 18 mm distal to the postero-lateral tip of the fibular head.

PURPOSE: The aim of the study was to evaluate the anatomical details of the articular branch of the peroneal nerve to the proximal tibiofibular joint and to project the height of its descent in relation to the fibular length. METHODS: Twenty-five lower extremities were included in the study. Following identification of the common peroneal nerve, its course was traced to its division into the deep and superficial peroneal nerve. The articular branch was identified. The postero-lateral tip of the fibular head was marked and the interval from this landmark to the diversion of the articular branch was measured. The length of the fibula, as the interval between the postero-lateral tip of the fibular head and the tip of the lateral malleolus, was evaluated. The quotient of descending point of the articular branch in relation to the individual fibular length was calculated. RESULTS: The articular branch descended either from the common peroneal nerve or the deep peroneal nerve. The descending point was located at a mean height of 18.1 mm distal to the postero-lateral tip of the fibular head. Concerning the relation to the fibular length, this was at a mean of 5.1%, starting from the same reference point. CONCLUSION: The articular branch of the common peroneal nerve was located at a mean height of 18.1 mm distal to the the postero-lateral tip of the fibular head, respectively, at a mean of 5.1% of the whole fibular length starting from the same reference point. These details represent a convenient orientation during surgical treatment of intraneural ganglia of the common peroneal nerve, which may result directly from knee trauma and indirectly from ankle sprain.

Physeal-sparing posteromedial portal approach reduced distance between guide pin and neurovascular structures.

PURPOSE: To compare a femoral physeal sparing anterior cruciate ligament (ACL) reconstruction technique utilizing a posteromedial portal to traditional transphyseal techniques with regards to anatomic tunnel positioning and proximity to important neurovascular structures. METHODS: Eight cadaveric knees were obtained for the study. Femoral tunnel guide pins were placed utilizing four different techniques: accessory anterior medial portal, posteromedial portal, trans-tibial, and figure-4 methods. The knees were then dissected and the following measurements taken: distance of each pin to the saphenous and peroneal nerve, popliteus tendon, neurovascular bundle, femoral ACL footprint and articular cartilage, and the angle of the guide pin entering the lateral femoral condyle. Fluoroscopic imaging was taken to determine the disruption of the physeal scar. RESULTS: Posteromedial portal guide pin was significantly closer to the neurovascular bundle, popliteal tendon and saphenous nerve when compared to the other 3 techniques, but was further from the peroneal nerve. It also had the smallest distance from the anatomic footprint of the ACL, and the largest angle to the lateral femoral condyle. The posteromedial portal guide pin had similar distance from the articular cartilage as the accessory anterior medial portal and figure-4 guide pin, with the trans-tibial guide pin being the farthest. The posteromedial portal guide pin failed to disrupt the physeal scar in all specimens, while the other three techniques consistently violated the physeal scar. CONCLUSION: The posteromedial portal technique offers an appropriate method for anatomic ACL reconstruction while protecting the distal femoral physis from injury. Care needs to be taken with this technique as it comes in closer proximity to some of the important neurovascular structures. This study indicates that posteromedial portal technique is a less technically challenging approach for physeal-sparing ACL repair with special attention required for the protection of neurovascular bundle from potential injury.

Communications between the superficial and deep fibular nerves in the foot: An anatomical and electrophysiological study.

INTRODUCTION: The deep fibular sensory nerve can be recorded to evaluate for peripheral nerve injury; however, it can be challenging in some individuals. Anatomic variation could account for some of this difficulty. Cadaver dissection and electrophysiological testing were used to characterize deep and superficial fibular sensory nerve supply to the foot. MATERIALS AND METHODS: Nineteen feet from 15 (8 males and 7 females) cadavers were dissected to identify the deep fibular nerves (DFNs) and superficial fibular nerves (SFNs). Sensation to the first dorsal web space was tested electrophysiologically in 101 participants (31 males and 70 females) with an age range of 18-47 years with stimulation over both DFNs and SFNs. RESULTS: Eleven of the 19 (58%) cadaver limbs had a communication between SFNs and DFNs in the dorsum of the foot. A reliable sensory response was recorded in the first dorsal web space in 88% of the limbs tested. Deep fibular stimulation alone produced a response in 34% of the limbs, while superficial fibular stimulation alone produced a response in 10% of the limbs. A separate response with stimulation of both the DFNs and SFNs was recorded in 44% of the limbs. CONCLUSIONS: A functional superficial to deep fibular sensory communication is present in a significant portion of the population. Those with the communication may not have the isolated sensory loss that would be expected in the first dorsal web space in conditions impacting the DFNs.

Ultrasound Imaging of the Deep Peroneal Nerve.

Ultrasound is considered an excellent imaging modality to evaluate the nerves of the limbs. The deep peroneal nerve (DPN) is one of the terminal branches of the common peroneal nerve. The DPN may be affected by various disorders, which may be clinically challenging to show. This Pictorial Essay reviews the normal ultrasound anatomy of the DPN and presents disorders that may involve the nerve and its main branches along its course, from proximal to distal.

Superficial peroneal nerve accessory artery (SPNAA) flap for head and neck reconstruction: A cadaveric anatomical study and retrospective case series review.

BACKGROUND: Several different flaps can reconstruct intraoral defects or lower limb deficits after free fibula osteo-cutaneous flap harvesting for jaw reconstructions. However, commonly used options may not be available for various reasons and can be associated with significant morbidity. We hypothesized that flaps supplied by the superficial peroneal nerve accessory artery (SPNAA) could be a viable alternative reconstructive option. METHODS: We describe the SPNAA's anatomy using 20 human cadaveric leg dissections and report eight cases involving SPNAA-based perforator flap reconstructions (six propeller flaps and two free flaps) in a retrospective case series. Patient-specific baseline variables and intraoperative and postoperative outcomes are described. RESULTS: Cadaveric dissection suggests that the location of the SPNAA is reliable but its origin varies, with 40% (N = 8) of SPNAAs being of type I origin, 20% type II (N = 4), and 40% (N = 8) type III in our series. All reconstructions were successful. No intraoperative complications occurred during propeller or free-flap reconstructions. No flap failures occurred. One propeller reconstruction showed distal superficial skin necrosis and one donor site wound dehisced; both were successfully managed conservatively. No other short-term or long-term complications occurred. CONCLUSIONS: Flaps based on SPNAA perforators appear effective, reliable, and safe reconstructive methods for covering fibula osteocutaneous donor site defects and for intraoral reconstructions. Controlled trials are required to compare its effectiveness and safety with other reconstructive methods.

Recurrent position and innervation pattern of recurrent peroneal nerve: A cadaveric study.

BACKGROUND: The recurrent peroneal nerve (RPN) branches from the common peroneal nerve or the deep peroneal nerve and it innervates to the lower patellar region. It has recently been reported that damage to the RPN causes pain in the lower patellar region; therefore, this study examined the recurrent position and the innervation pattern of the RPN. METHODS: Cases of knee deformity or atrophy were excluded, and 50 legs (25 males and 25 females) of 34 cadavers (15 males and 19 females) were examined to assess the recurrent position and the innervation pattern of the RPN. RESULTS: The recurrent position of the RPN was 27.9 ± 3.6 mm from the tip of the fibula. The RPN innervated to the patellar tendon in five of the 50 legs (10%), to the infrapatellar fat pad in 13 legs (26%), and to both the patellar tendon and the infrapatellar fat pad in 20 legs (40%), and to neither the patellar tendon nor the infrapatellar fat pad in 12 legs (24%). No significant sex differences were observed in the recurrent position and the innervation pattern of the RPN. CONCLUSIONS: In all cases, the recurrent position of the RPN was almost fixed from the tip of the fibula. The RPN frequently innervated to the patellar tendon or the infrapatellar fat pad (76%) in both males and females. These findings would be useful in knee surgery to preserve the RPN or for the diagnosis of pain in the lower patellar region.