Tibial and Common Fibular Nerve Block in the Popliteal Fossa with Single Puncture Using Percutaneous Nerve Stimulator: Anatomical Considerations and Ultrasound Description

Introduction: The direction and magnitude of nerve mobility in the lower extremity has been quantified in fixed cadaveric tissue but extrapolation of findings to live humans is limited. Ultrasound is an emerging tool for in vivo imaging of soft tissues such as peripheral nerve. The purpose of this study was to investigate in vivo excursion of the tibial and common fibular nerves in the popliteal fossa during limb positioning in healthy participants.Methods: Real time ultrasound imaging of the tibial and common fibular nerves in the popliteal fossa was performed on 5 healthy subjects using a Siemens Acuson Sequoia machine. Imaging was performed while the ankle was moved through plantar and dorsiflexion in two hip positions.Results: The tibial nerve glided proximal, deep and lateral during plantar flexion and distal, superficial and medial during dorsiflexion. The common fibular nerve glided superficial and lateral during plantar flexion and deep and medial during dorsiflexion.Conclusions: The tibial and common fibular nerves have significant mobility in both the transverse and sagittal planes during ankle motion. The direction of proximal and distal excursion of the tibial nerve is consistent with previous cadaveric studies. Ultrasound imaging is an effective, non‐invasive way to investigate movement of the large peripheral nerves in the lower extremity.

Development and verification of saphenous, tibial and common peroneal nerve block techniques for analgesia below the thigh in the nonchondrodystrophoid dog

Pediatric Regional Anesthesia: Beyond the Caudal

P-NU003. Estimation of cross-sectional area reference values of nerves in the upper and lower extremities using ultrasonography in the Indian population

OBJECT Knee dislocations are often accompanied by stretch injuries to the common peroneal nerve (CPN). A small subset of these injuries also affect the tibial nerve. The mechanism of this combined pattern could be a single longitudinal stretch injury of the CPN extending to the sciatic bifurcation (and tibial division) or separate injuries of both the CPN and tibial nerve, either at the level of the tibiofemoral joint or distally at the soleal sling and fibular neck. The authors reviewed cases involving patients with knee dislocations with CPN and tibial nerve injuries to determine the localization of the combined injury and correlation between degree of MRI appearance and clinical severity of nerve injury. METHODS Three groups of cases were reviewed. Group 1 consisted of knee dislocations with clinical evidence of nerve injury (n = 28, including 19 cases of complete CPN injury); Group 2 consisted of knee dislocations without clinical evidence of nerve injury (n = 19); and Group 3 consisted of cases of minor knee trauma but without knee dislocation (n = 14). All patients had an MRI study of the knee performed within 3 months of injury. MRI appearance of tibial and common peroneal nerve injury was scored by 2 independent radiologists in 3 zones (Zone I, sciatic bifurcation; Zone II, knee joint; and Zone III, soleal sling and fibular neck) on a severity scale of 1-4. Injury signal was scored as diffuse or focal for each nerve in each of the 3 zones. A clinical score was also calculated based on Medical Research Council scores for strength in the tibial and peroneal nerve distributions, combined with electrophysiological data, when available, and correlated with the MRI injury score. RESULTS Nearly all of the nerve segments visualized in Groups 1 and 2 demonstrated some degree of injury on MRI (95%), compared with 12% of nerve segments in Group 3. MRI nerve injury scores were significantly more severe in Group 1 relative to Group 2 (2.06 vs 1.24, p < 0.001) and Group 2 relative to Group 3 (1.24 vs 0.13, p < 0.001). In both groups of patients with knee dislocations (Groups 1 and 2), the MRI nerve injury score was significantly higher for CPN than tibial nerve (2.72 vs 1.40 for Group 1, p < 0.001; 1.39 vs 1.09 for Group 2, p < 0.05). The clinical injury score had a significantly strong correlation with the MRI injury score for the CPN (r = 0.75, p < 0.001), but not for the tibial nerve (r = 0.07, p = 0.83). CONCLUSIONS MRI is highly sensitive in detecting subclinical nerve injury. In knee dislocation, clinical tibial nerve injury is always associated with simultaneous CPN injury, but tibial nerve function is never worse than peroneal nerve function. The point of maximum injury can occur in any of 3 zones.

Evaluation of the potential efficacy of an ultrasound-guided adductor canal block technique in dog cadavers

Involuntary, Electrically Excitable Nerve Transfer for Denervation: Results From an Animal Model

Randomized Trial of Percutaneous Tibial Nerve Stimulation Versus Sham Efficacy in the Treatment of Overactive Bladder Syndrome: Results From the SUmiT Trial

Randomized Trial of Percutaneous Tibial Nerve Stimulation Versus Extended-Release Tolterodine: Results From the Overactive Bladder Innovative Therapy Trial

Peripheral nerve stimulation (PNS) of the lower extremity has progressed significantly over the last decade. From the proof of concept that ultrasound-guided, percutaneous implantation was possible to advances in waveforms, the field has been rapidly evolving. While most nerves in the lower extremity can be PNS targets, consideration must be given to the ergonomics of pulse generator placement, patient comfort, and avoidance of lead migration. For this paper, we examine some of the conditions amenable to lower extremity PNS, review the evidence and history behind PNS for these conditions, and describe approaches for the tibial, sural, and superficial peroneal nerves. A literature search was conducted using PubMed. Search terms used were "peripheral nerve stimulation," "lower extremity entrapment neuropathies," "sural nerve," "superficial peroneal nerve," "tibial nerve," and "tarsal tunnel syndrome." Emphasis was placed on randomized controlled studies, anatomical dissections, and comprehensive review articles. Approaches to nerves and ultrasound images were based on anecdotal PNS cases from an experienced implanter (SP). The development of ultrasound as a viable method of image guidance for percutaneous peripheral nerve stimulation has led to an exponential growth in the field. Lower extremity percutaneous lead placement is both feasible and an appropriate treatment modality for certain pain conditions.

Background and Objectives: Peripheral nerve stimulation (PNS) is analgesic for some lower extremity neuropathic pain syndromes. PNS currently involves open surgical placement of electrode(s). Increasingly, ultrasound guidance is used for perioperative neural block. Minimally invasive placement of PNS electrodes for lower extremity targets using ultrasound guidance has not been reported. We hypothesized that ultrasound-guided placement of PNS electrodes was feasible. Methods: Four cadaver mid-thigh transected fresh frozen specimens were studied. Specimens were scanned utilizing a 14 to 7 MHz linear probe and electrodes were placed proximal to the tibial, peroneal, and sciatic nerves at various locations. Anatomical dissection was performed to check placement accuracy and evaluate for grossly visible neural injuries. Results: Acceptable locations for ultrasound-guided electrode placement were: (1) tibial nerve, approximately 8 to 14 cm superior to the medial malleolus above the tarsal tunnel, or at the upper popliteal fossa; (2) peroneal nerve, approximately 2 to 4 cm inferior to the lateral fibular head or at the upper popliteal fossa; (3) sciatic nerve immediately superior to the bifurcation (high popliteal area); and (4) lateral sural nerve at the lower popliteal fossa. No grossly visible neural injuries were seen. Electrode placements appeared to be in satisfactory locations for stimulation. Conclusions: Ultrasound imaging to facilitate peripheral nerve electrode placement is feasible. This new minimally invasive approach to lead placement requires further study to determine trial implantation criteria, optimal locations, anchoring techniques, and best clinical practice.

Feasibility of Ultrasound-Guided Percutaneous Placement of Peripheral Nerve Stimulation Electrodes in a Cadaver Model: Part One, Lower Extremity

Incomplete sensory blockade of the foot after sciatic nerve block in the popliteal fossa may be related to the motor response that was elicited when the block was performed. We investigated the appropriate motor response when a nerve stimulator is used in sciatic nerve block at the popliteal fossa. Six volunteers classified as American Society of Anesthesiologists' physical status I underwent 24 sciatic nerve blocks. Each volunteer had four sciatic nerve blocks. During each block, the needle was placed to evoke one of the following motor responses of the foot: eversion, inversion, plantar flexion, or dorsiflexion. Forty milliliters 1.5% lidocaine was injected after the motor response was elicited at < 1 mA intensity. Sensory blockade of the areas of the foot innervated by the posterior tibial, deep peroneal, superficial peroneal, and sural nerves was checked in a blinded manner. Motor blockade was graded on a three-point scale. The width of the sciatic nerve and the orientation of the tibial and common peroneal nerves were also examined in 10 cadavers. A significantly greater number of posterior tibial, deep peroneal, superficial peroneal, and sural nerves were blocked when inversion or dorsiflexion was seen before injection than after eversion or plantar flexion (P < 0.05). Motor blockade of the foot was significantly greater after inversion. Anatomically, the tibial and common peroneal nerves may be separate from each other throughout their course. The sciatic nerve ranged from 0.9-1.5 cm in width and was divided into the tibial and common peroneal nerves at 8 +/- 3 (range, 4-13) cm above the popliteal crease. Inversion is the motor response that best predicts complete sensory blockade of the foot. Incomplete blockade of the sciatic nerve may be a result of the size of the sciatic nerve, to separate fascial coverings of the tibial and common peroneal nerves, or to blockade of either the tibial or common peroneal nerves after branching from the sciatic nerve.

The sciatic nerve (SN) presented with unusual patterns in which five smaller fibers instead of one or two nerves at the level of the Piriformis muscle. Those five fibers measured 7.5 cm from their origin to where they joined to form the SN. The SN terminated in the popliteal fossa by giving rise to three terminal branches: the tibial nerve, the common peroneal nerve, and another unusual nerve that supplied the medial head of the gastrocnemius. This case is unusual because the SN presents with different positional variations of its two components in relation to the piriformis muscle but not five fibers; in addition, the SN normally bifurcates instead of trifurcating when it reaches in the popliteal fossa. The case presented a Type A pattern of SN to the piriformis muscle. This type of pattern has been documented to be the most common in some parts of Africa. Some authors have reported two patterns of trifurcation of the SN. One is a pattern where the SN gave rise to the tibial, superficial, and deep peroneal nerves at the popliteal fossa, and another is a trifurcation pattern where it gave rise to the tibial, common peroneal, and sural nerves. The case is different as it presents an unusual unreported pattern where the SN trifurcates by giving rise to the tibial, common peroneal, and nerve that supplies the medial head of the gastrocnemius muscle. The current variation has never been reported elsewhere.

This case report describes an uncommon compressive neuropathy involving both the common peroneal and tibial nerves as they pass through the popliteal fossa. The patient is a 16-year-old male who sustained a right knee fracture-dislocation. There was disruption of the popliteal artery, which was repaired with a reversed saphenous vein graft. This surgery was complicated by a postoperative hematoma. After drainage of the hematoma, the patient developed a progression neuropathy over the next 6 months that involved the common peroneal nerve and to a lesser extent the tibial nerve. Foot drop, muscle wasting of posterior and anteriolateral compartment and sensory loss over the dorsal foot and lateral leg were also documented. Based on the history, clinical finding and electrodiagnostic studies, the patient had both a tibial and common peroneal neuropathy. The neuropathy was related to the accident, but the exact etiology was unknown prior to surgical exploration. Surgical exploration was performed 15 months following the injury after referral to our institution and thick fibrous scar tissue was found compressing both tibial and common peroneal nerves. These bands were released and complete internal neurolysis was performed on both nerves. Although uncommon, surgical nerve compression can occur following extensive scarring secondary to trauma or surgical procedures. This discussion will describe the history of compressive neuropathies in the popliteal fossa. We will review the relevant literature and anatomy of this disease and describe disease progression and treatment options.