Peroneal nerve location at the fibular head: an anatomic study using 3D imaging

Matched-Pair Analysis of Magnetic Resonance Images for Location of the Common Peroneal Nerve in Valgus Knees: Comparison with the Varus Knees

This study aimed to assess the distance and angular location of the common peroneal nerve (CPN) on axial magnetic resonance imaging (MRI) in the valgus knees and compare the measurements with those obtained from the control group. We compared the location of the CPN according to the type of alignment by performing a subgroup analysis. From January 2009 to December 2019, we identified 41 knees with preoperative MRI in patients who underwent total knee arthroplasty (TKA) for valgus deformity (valgus group). We performed one-to-two matched-pair analysis to a cohort of patients who underwent MRI but were not candidates for TKA (control group), according to sex and age. The valgus group was classified according to the grading system reported by Ranawat et al, and the control group was also subdivided according to the hip-knee-ankle (HKA) angle obtained from lower extremity scanography: neutral (-3 to +3 degrees from the neutral mechanical axis), valgus (> +3 degrees), and varus alignment (< -3 degrees). Distance between the CPN and posterolateral cortex of the tibia at the knee joint (distance J) and tibial cut level (distance C) were measured. Angle of the CPN from the central anteroposterior axis of the tibia (angle α) was measured. We compared the measurements between the groups. Distance J was significantly closer in the valgus group (p < 0.001), whereas angle α was significantly smaller in the valgus group (p < 0.001). However, no significant differences were found in the subgroup analysis. Moreover, a significant correlation was found between distance J and the HKA angle (p < 0.001). The location of the CPN in the valgus knees was closer to the posterolateral cortex of the tibia at the joint level and showed a smaller angle than that in the other aligned knees. We recommend that lateral soft tissue release for valgus knees should not be performed at the joint line. The results of this study suggest that this would be less safe than a release performed at the level of the proximal tibial bone resection.

Minimally Invasive Surgical Approach for Open Common Peroneal Nerve Neurolysis in the Setting of Previous Posterior Schwannoma Removal

The common peroneal nerve (CPN) runs laterally around the fibular neck and enters the peroneal tunnel, where it divides into the deep, superficial, and recurrent peroneal nerves. CPN entrapment is the most common neuropathy of the lower extremity and is vulnerable at the fibular neck because of its superficial location. Schwannomas are benign, encapsulated tumors of the nerve sheath that can occur sporadically or in cases of neurocutaneous conditions, such neurofibromatosis type 2. In cases with compressive neuropathy resulting in significant or progressive motor loss, decompression and neurolysis should be attempted. We present a technical note for the treatment of CPN compressive neuropathy in the setting of a previous ipsilateral schwannoma removal with a minimally invasive surgical approach and neurolysis of the CPN at the fibular neck.

Shear wave elastography of the common fibular nerve at the fibular head

ABSTRACT

The aim of this work is to study the sonoelastographic features of the common fibular nerve in healthy adult subjects.This is an observational cross-sectional study. Shear wave elastography was used to evaluate the common fibular nerve. Crosssectional area and stiffness were measured in kilopascal (kPa) and meters/second (m/s).The study included 82 common fibular nerves in 41 healthy adult subjects. The mean cross-sectional area of the common fibular nerve at the fibular head was 8.7 mm2. Positive correlation was noted between stiffness measurements between short and long axes by both methods. The mean stiffness of the common fibular nerve in the short axis was 22.5 kPa, and in the long axis (LA) was 35.4 kPa. Positive correlation was noted between height and stiffness measured by both methods in both axes by kPa. In m/s, the mean stiffness of the common fibular in the short axis was 2.6 m/s, and while in the LA was 3.4 m/s. Height showed positive correlation with both axes for stiff measurements in m\s. Weight showed positive correlation with stiffness measurements by m/s in the LA.The results obtained in our study could be a reference point for evaluating stiffness of the common fibular nerve in research involving different pathologies.

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.

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.

Proximal tibiofibular joint changes after closed-wedge high tibial osteotomy. Are they relevant?

BACKGROUND

There is some controversy about how the proximal tibiofibular joint (PTFJ) capsulotomy changes PTFJ anatomy in closed-wedge high tibial osteotomy (CW-HTO) and about how this affects ankle and knee mobility and the onset of lateral knee pain. The aim of this study is to evaluate changes in PTFJ after CW-HTO, and its possible clinical significance.

METHODS

This study includes 50 patients who underwent CW-HTO with tibiofibular capsulotomy from 2000 to 2018 in our hospital. A clinical evaluation was conducted to evaluate pain location. The degrees of osteoarthritis and the proximal fibular subluxation were evaluated on radiographs. A dynamic analysis of the PTFJ was also performed comparing proximal fibular head subluxation on anteroposterior knee radiographs with the ankle placed in neutral position and dorsiflexed.

RESULTS

The clinical evaluation revealed that two patients had a sore scar, five had pain on the PTFJ with manual compression, and none referred lateral compartment pain. The radiological analysis revealed an average proximal subluxation of the fibular head after the osteotomy of 9.64 (range: 0-29) mm, which was greater in oblique PTFJ (p < 0.05). After the surgery, all the patients developed some degree of PTFJ arthritis. There was no correlation between lateral pain and proximal fibular subluxation, tibiofibular arthritis, or lateral compartment arthritis. The dynamic analysis revealed no significant changes.

CONCLUSIONS

After CW-HTO all the patients developed proximal subluxation of the fibular head and a variable degree of PTFJ osteoarthritis, but these changes seem to be unrelated with lateral knee pain.

A reproducible reference point for the common peroneal nerve during surgery at the posterolateral corner of the knee: a cadaveric study

Background

This is an experimental study conducted to assess whether the fibular head is a reliable reference point to identify the position of the common peroneal nerve at the posterolateral corner of the knee.

Materials and methods

Twelve cadaveric knees were dissected through the lateral approach. The common peroneal nerve was identified and traced. The location where the common peroneal nerve crossed the posterior border of the biceps femoris and the posterior border of the fibular neck were designated as points B and N, respectively. The tip of the fibular head was designated F. Distances FB and FN were measured and the triangular area FBN was calculated at various degrees of knee flexion.

Results

During knee motion, distance FN showed minimal change and was not affected by variation in degrees of knee flexion (p = 0.131). Distance FB and distance BN were affected by variation in degrees of knee flexion (p < 0.001). Triangular area FBN increased in size up to 60° of knee flexion measuring 621.22 mm² and subsequently decreased with further knee flexion.

Conclusion

The common peroneal nerve can consistently be found at approximately 20.7 ± 1 mm on the fibular neck with respect to the tip of the fibular head. The tip of the fibular head is a consistent landmark that can be used to predict the position of the exit point of the common peroneal nerve at the posterolateral corner of the knee.