Anatomic Delineation of Tarsal Tunnel Innervation via Ultrasonography

Patient Satisfaction with Surgery for Tarsal- and Carpal- Tunnel Syndrome - Comparative Study

We compared the treatment satisfaction of patients who had undergone surgery for tarsal tunnel syndrome (TTS) and carpal tunnel syndrome (CTS). We enrolled 44 patients in this study; 23 were operated for CTS and 21 for TTS. All patients had received surgery under a microscope and under local anesthesia. Using the numerical rating scale (NRS) for numbness/pain (range 0-10) we compared their preoperative outcome expectations with their satisfaction with our treatment 6 months after the operation. We also recorded their pre- and postoperative EuroQol 5-dimension 5-level (EQ-5D-5L) scale for their health-related quality of life (QOL). The subjective assessment of their QOL showed that it was significantly lower in TTS- than CTS patients both pre- and postoperatively. Six months after the operation, the NRS for symptoms and the (EQ-5D-5L) scale for the QOL were significantly improved in TTS- and CTS patients; however, these scores were significantly better after CTS- than TTS surgery. Also, the postoperative NRS was significantly lower in the CTS- than the TTS patients. Our comparison of the patients' expected- and actual surgical outcome showed that the result was better than expected after CTS- and TTS surgery; in CTS patients the difference was significant. Overall, CTS- were more satisfied than TTS patients with the treatment outcome. Satisfaction with the treatment was greater after CTS- than TTS surgery. TTS- experienced less symptom relief than CTS patients although the actual- exceeded the expected outcome in patients operated for TTS.

Magnetic Resonance Imaging Findings in Patients with Tarsal Tunnel Syndrome

Tarsal tunnel syndrome (TTS) is a common entrapment syndrome whose diagnosis can be difficult. We compared preoperative magnetic resonance imaging (MRI) and operative findings in 23 consecutive TTS patients (28 sides) whose mean age was 74.5 years. The 1.5T MRI sequence was 3D T2* fat suppression. We compared the MRI findings with surgical records and intraoperative videos to evaluate them. MRI- and surgical findings revealed that a ganglion was involved on one side (3.6%), and the other 27 sides were diagnosed with idiopathic TTS. MRI visualized the nerve compression point on 23 sides (82.1%) but failed to reveal details required for surgical planning. During surgery of the other five sides (17.9%), three involved varices, and on one side each, there was connective tissue entrapment or nerve compression due to small vascular branch strangulation. MRI studies were useful for nerve compression due to a mass lesion or idiopathic factors. Although MRI revealed the compression site, it failed to identify the specific involvement of varices and small vessel branches and the presence of connective tissue entrapment.

An Update on Posterior Tarsal Tunnel Syndrome

Posterior tarsal tunnel syndrome (PTTS) is an entrapment neuropathy due to compression of the tibial nerve or one of its terminal branches within the tarsal tunnel in the medial ankle. The tarsal tunnel is formed by the flexor retinaculum, while the floor is composed of the distal tibia, talus, and calcaneal bones. The tarsal tunnel contains a number of significant structures, including the tendons of 3 muscles as well as the posterior tibial artery, vein, and nerve. Focal compressive neuropathy of PTTS can originate from anything that physically restricts the volume of the tarsal tunnel. The variety of etiologies includes distinct movements of the foot, trauma, vascular disorders, soft tissue inflammation, diabetes mellitus, compression lesions, bony lesions, masses, lower extremity edema, and postoperative injury. Generally, compression of the posterior tibial nerve results in clinical findings consisting of numbness, burning, and painful paresthesia in the heel, medial ankle, and plantar surface of the foot. Diagnosis of PTTS can be made with the presence of a positive Tinel sign in combination with the physical symptoms of pain and numbness along the plantar and medial surfaces of the foot. Initially, patients are treated conservatively unless there are signs of muscle atrophy or motor nerve involvement. Conservative treatment includes activity modification, heat, cryotherapy, non-steroidal anti-inflammatory drugs, corticosteroid injections, opioids, GABA analog medications, tricyclic antidepressants, vitamin B-complex supplements, physical therapy, and custom orthotics. If PTTS is recalcitrant to conservative treatment, standard open surgical decompression of the flexor retinaculum is indicated. In recent years, a number of alternative minimally invasive treatment options have been investigated, but these studies have small sample sizes or were conducted on cadaveric models.

Ultrasound-Guided Near-Nerve Needle Sensory Technique for the Diagnosis of Tarsal Tunnel Syndrome

Background: Tarsal tunnel syndrome (TTS) is one of the most common entrapment syndromes. Although diagnosis is supported by imaging tests, it has so far been based on clinical findings. Neurophysiological tests are not effective for providing an accurate diagnosis. The objective of this study was to analyze the efficacy of the ultrasound-guided near-nerve needle sensory technique (USG-NNNS) for the diagnosis of TTS Methods: The study population comprised 40 patients referred for a neurophysiological study owing to clinical suspicion of TTS. Routine neurophysiological tests were performed and compared with the results of USG-NNNS. Results: The diagnosis of TTS was achieved in 90% of cases. We found significant differences between lateral plantar sensory recordings with surface electrodes and USG-NNNS techniques for amplitude, nerve conduction velocity (NCV), and duration. As for the medial plantar sensory recordings, differences were found only for duration. No responses were obtained with surface electrode studies in 64.8% of cases. In addition, we observed normal sensory NCV with surface electrodes in 20 patients, although this decreased when the NNNS technique was used. Conclusions: This is the first report of the efficacy of the USG-NNNS technique for confirming the diagnosis of TTS.

Redefining the Topography of the Tibial Nerve: Updated Treatment Guide for Tibial Nerve Entrapments: An Addendum to Surgical Treatment Protocol for Peripheral Nerve Dysfunction of the Lower Extremity: A Systematic Approach

Dysfunction of the tibial nerve can progress to painful and potentially disabling conditions. There are multiple sites of entrapment along the course of the tibial nerve. Detailed knowledge of the anatomy and anatomic variations is critical for a surgeon to be able to properly diagnose and treat patients with tibial nerve injuries. Repair of tibial nerve injuries involves a thorough history, physical examination, diagnostic studies, and microsurgical techniques. This article discusses sites of tibial nerve entrapment and use of a surgical algorithm that provides a systematic approach that has been successful within the literature in treating chronic tibial neuritic pain.

Anatomical study and branching point of neurovascular structures at the medial side of the ankle

Nerve entrapment and blood circulation impairment associated with the medial side of the ankle are not uncommon. The purpose of this study was to describe the anatomical basis of neurovascular structures of the medial ankle which comprised the number, origin, branching pattern, and branching point. Forty feet of fresh cadavers were examined by using 2 reference lines: the malleolar-calcaneal (MC) and navicular-calcaneal (NC) axes. We recorded number, origin, length of the 2 axes, the locations and widths of neurovascular structures on MC and NC axes, the branching point of neurovascular structures, and the branching pattern of neurovascular structures was recorded and was separated into 5 types. The posterior tibial nerve (PTN) bifurcated to plantar and calcaneal nerves and branched proximally to the tarsal tunnel (TT). The posterior tibial artery bifurcated to plantar and calcaneal arteries and branched inferiorly to PTN and within the TT. The calcaneal nerves and arteries had more variation of number and origin. The most common branching point of calcaneal nerves and arteries is within the TT, except the medial calcaneal nerve. It branched proximally to the TT. The anatomical knowledge from this study is important for the diagnosis and treatment of clinicians.

Results of ultrasound-guided release of tarsal tunnel syndrome: a review of 81 cases with a minimum follow-up of 18 months

Background

This study aims to analyse the clinical results of ultrasound-guided surgery for the decompression of the tibial nerve, including its distal medial and lateral branches, to treat tarsal tunnel syndrome. These structures are the complete flexor retinaculum and the deep fascia of the abductor hallucis muscle, including individualised release of the medial and lateral plantar nerve tunnels.

Method

This is a retrospective review of 81 patients (36 men and 45 women) with an average age of 41 years old (32–62) and an average clinical course of 31 months (8–96) compatible with idiopathic tarsal tunnel syndrome, who underwent ultrasound-guided decompression of the proximal and distal tarsal tunnel between February 2015 and November 2017 (both months included), with a minimum follow-up of 18 months.

Results

Based on the Takakura et al. scale for the 81 patients, 76.54% obtained excellent results, 13.58% good results, and 9.87% poor results.

The patients with the longest course of symptoms displayed the worst results.

Conclusion

Although 9% of patients did not improve, ultrasound-guided tarsal tunnel release might be a viable alternative to conventional open approaches.

Ultrasound-Guided Release of the Tibial Nerve and Its Distal Branches: A Cadaveric Study

OBJECTIVES

The purpose of the study was to determine whether ultrasound (US)-guided surgery is a viable type of surgery for performing an effective release/decompression of the constricting structures that are responsible for focal nerve compression in tarsal tunnel syndrome.

METHODS

Ultrasound guidance was used on cadaveric specimens to delineate the anatomic course of the nerves and vessels in the medial ankle that comprise the structures involved in tarsal tunnel syndrome. Ultrasound guidance was used on cadaveric specimens and assisted in delineating a safe surgical zone to adequately and effectively release these constrictive structures of the proximal and distal tarsal tunnels. The US-guided tarsal tunnel release/decompression was performed through 2 small 1- to 2-mm portals. After US-guided release, anatomic dissection was used to check the efficacy (release of the flexor retinaculum and deep abductor hallucis muscle) and safety (absence of neurovascular or tendon injury) of the procedure.

RESULTS

In 12 fresh cadaveric specimens, US-guided release of the tibial nerve (proximal tarsal tunnel) and its branches (distal tarsal tunnel) at the medial ankle was effective in all 12 specimens (100% release rate), without any signs of compromise or injury into the neurovascular structures.

CONCLUSIONS

Ultrasound-guided tarsal tunnel release is a feasible surgical procedure that can be safe and effective with the proper training, although further investigation is warranted. This type of surgery may promote faster recovery with less postoperative morbidity, including pain, but this will be the subject of a further investigation.

Ultrasound-guided decompression surgery of the tarsal tunnel: a novel technique for the proximal tarsal tunnel syndrome-Part II

Background

The aim of this study is to provide a safe ultrasound-guided minimally invasive surgical approach for a proximal tarsal tunnel release concerning nerve entrapments.

Methods and results

The study was carried out on ten fresh-frozen feet. All of them were examined by high resolution ultrasound at the medial ankle region. The surgical approach was marked throughout the course of the flexor retinaculum (laciniate ligament). Once the previous steps were done, the flexor retinaculum release technique was carried out with a 2-mm entry only. As a result, an effective and safe release of the flexor retinaculum was obtained in all fresh-frozen feet.

Conclusion

The results of our anatomic study indicate that our novel ultrasound-guided minimally invasive surgical approach for the release of the flexor retinaculum might be an effective, safe and quick decompression technique treating selected patients with a proximal tarsal tunnel syndrome.

Clinical-anatomic mapping of the tarsal tunnel with regard to Baxter's neuropathy in recalcitrant heel pain syndrome: part I

Purpose

Neuropathy of the Baxter nerve (BN) seems to be the first cause of the heel pain syndrome (HPS) of neurological origin.

Methods

41 alcohol–glycerol embalmed feet were dissected. We documented the pattern of the branches of the tibial nerve (TN) and describe all relevant osteofibrous structures. Measurements for the TN branches were related to the Dellon–McKinnon malleolar-calcaneal line also called DM line (DML) for the proximal TT and the Heimkes Triangle for the distal TT. Additionally, we performed an ultrasound-guided injection procedure of the BN and provide an algorithm for clinical usage.

Results

The division of the TN was 16.4 mm proximal to the DML. The BN branches off 20 mm above the DML center or 30 mm distally to it. In most of the cases, the medial calcaneal branch (MCB) originated from the TN proximal to the bifurcation. Possible entrapment spots for the medial and lateral plantar nerve (MPN, LPN), the BN and the MCB are found within a circle of 5 mm radius with a probability of 80%, 83%, and 84%, respectively. In ten out of ten feet, the US-guided injection was precisely allocated around the BN.

Conclusions

Our detailed mapping of the TN branches and their osteofibrous tubes at the TT might be of importance for foot and ankle surgeons during minimally invasive procedures in HPS such as ultrasound-guided ankle and foot decompression surgery (UGAFDS).

Indications for neuromuscular ultrasound: Expert opinion and review of the literature

Over the last two decades, dozens of applications have emerged for ultrasonography in neuromuscular disorders. We wanted to measure its impact on practice in laboratories where the technique is in frequent use. After identifying experts in neuromuscular ultrasound and electrodiagnosis, we assessed their use of ultrasonography for different indications and their expectations for its future evolution. We then identified the earliest papers to provide convincing evidence of the utility of ultrasound for particular indications and analyzed the relationship of their date of publication with expert usage. We found that experts use ultrasonography often for inflammatory, hereditary, traumatic, compressive and neoplastic neuropathies, and somewhat less often for neuronopathies and myopathies. Usage significantly correlated with the timing of key publications in the field. We review these findings and the extensive evidence supporting the value of neuromuscular ultrasound. Advancement of the field of clinical neurophysiology depends on widespread translation of these findings.