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

Safety and efficacy of ultrasound-guided percutaneous flexor retinaculum release of the ankle: an anatomical study

Background

Tarsal tunnel syndrome (TTS) is a condition in which the tibial nerve (TN) (or its terminal branches) is compressed by the flexor retinaculum (FR) and the deep fascia of the abductor hallucis muscle at the tarsal tunnel, causing symptoms that negatively impact the patient's quality of life, including numbness, a sensation of a foreign object, coldness, and pain. FR release via microtrauma using needle-knife has proven to be effective in China and is widely used by clinicians. The traditional acupotomy, however, is the "blind knife" treatment, which cannot guarantee patient safety due to risk of injury to important structures, particularly the neurovascular bundle. Compared with the conventional treatments, ultrasound-guided percutaneous FR release possesses noteworthy advantages including high efficacy and safety.

Methods

Percutaneous release of the FR was performed on 51 formalin-fixed specimens. The specimens were divided into two groups: an ultrasound-guided acupotomy pushing group comprising 20 legs (group U) and a nonultrasound-guided acupotomy pushing group comprising 31 legs (group N). After high-frequency ultrasound exploration, those with clear vascular imaging were included in group U; otherwise, they were included in group N. The FR was released percutaneously, soft tissue was dissected layer by layer, and anatomical data were recorded.

Results

There no cases of injury in group U (0%) and four in group N (12.9%). Among the different intervention methods, there were no significant differences in tissue injury types (χ2=2.80; P=0.09). The percentage of released FR in group U was 80.00% while that in group N was 61.29% (χ2=1.977; P=0.16), which did not represent a significant difference between the two groups. However, group U had a significantly greater release length than that in the group N (t=3.359; P=0.002), indicating that the flexor release length guided by ultrasound is significantly greater than the unguided one.

Conclusions

Ultrasound-guided percutaneous release of the FR using a needle-knife can provide greater length and percentage of released FR while maintaining a comparable safety rate to the unguided procedure.

Ganglia-Induced Tarsal Tunnel Syndrome

BACKGROUND

Tarsal tunnel syndrome (TTS) is a common entrapment neuropathy that is sometimes elicited by ganglia in the tarsal tunnel.

METHODS

Between August 2020 and July 2022, we operated on 117 sides with TTS. This retrospective study examined data from 8 consecutive patients (8 sides: 5 men, 3 women; average age 67.8 years) with an extraneural ganglion in the tarsal tunnel. We investigated the clinical characteristics and surgical outcomes for these patients.

RESULTS

The mass was palpable through the skin in 1 patient, detected intraoperatively in 1 patient, and visualized on MRI scanning in the other 6 patients. Symptoms involved the medial plantar nerve area (n = 5), lateral plantar nerve area (n = 1), and medial and lateral plantar nerve areas (n = 2). The interval between symptom onset and surgery ranged from 4 to 168 months. Adhesion between large (≥20 mm) ganglia and surrounding tissue and nerves was observed intraoperatively in 4 patients. Of the 8 patients, 7 underwent total ganglion resection. There were no surgery-related complications. On their last postoperative visit, 3 patients with a duration of symptoms not exceeding 10 months reported favorable outcomes.

CONCLUSIONS

Because ganglia eliciting TTS are often undetectable by skin palpation, imaging studies may be necessary. Early surgical intervention appears to yield favorable outcomes.

Sciatic and tibial neuropathies

The sciatic nerve is the body's largest peripheral nerve. Along with their two terminal divisions (tibial and fibular), their anatomic location makes them particularly vulnerable to trauma and iatrogenic injuries. A thorough understanding of the functional anatomy is required to adequately localize lesions in this lengthy neural pathway. Proximal disorders of the nerve can be challenging to precisely localize among a range of possibilities including lumbosacral pathology, radiculopathy, or piriformis syndrome. A correct diagnosis is based upon a thorough history and physical examination, which will then appropriately direct adjunctive investigations such as imaging and electrodiagnostic testing. Disorders of the sciatic nerve and its terminal branches are disabling for patients, and expert assessment by rehabilitation professionals is important in limiting their impact. Applying techniques established in the upper extremity, surgical reconstruction of lower extremity nerve dysfunction is rapidly improving and evolving. These new techniques, such as nerve transfers, require electrodiagnostic assessment of both the injured nerve(s) as well as healthy, potential donor nerves as part of a complete neurophysiological examination.

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.

The role of ultrasound-guided perineural injection of the tibial nerve with a sub-anesthetic dosage of lidocaine for the diagnosis of tarsal tunnel syndrome

Background

Tarsal tunnel syndrome (TTS) involves entrapment of the tibial nerve at the medial ankle beneath the flexor retinaculum and its branches, the medial and lateral plantar nerves, as they course through the porta pedis formed by the deep fascia of the abductor hallucis muscle. TTS is likely underdiagnosed, because diagnosis is based on clinical evaluation and history of present illness. The ultrasound-guided lidocaine infiltration test (USLIT) is a simple approach that may aid in the diagnosis of TTS and predict the response to neurolysis of the tibial nerve and its branches. Traditional electrophysiological testing cannot confirm the diagnosis and only adds to other findings.

Methods

We performed a prospective study of 61 patients (23 men and 38 women) with a mean age of 51 (29-78) years who were diagnosed with idiopathic TTS using the ultrasound guided near-nerve needle sensory technique (USG-NNNS). Patients subsequently underwent USLIT of the tibial nerve to assess the effect on pain reduction and neurophysiological changes.

Results

USLIT led to an improvement in symptoms and nerve conduction velocity. The objective improvement in nerve conduction velocity can be used to document the pre-operative functional capacity of the nerve. USLIT may also be used as a possible quantitative indicator of whether the nerve has the potential to improve in neurophysiological terms and ultimately inform prognosis after surgical decompression.

Conclusion

USLIT is a simple technique with potential predictive value that can help the clinician to confirm the diagnosis of TTS before surgical decompression.

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.