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.

Midarch Foot Pain: Entrapment Neuropathy of the Distal Medial Plantar Nerve and Its Branches.

Medial forefoot pain, or midarch pain, is usually attributed to plantar fasciitis. The authors present their findings of a previously unreported nerve entrapment of the medial proper plantar digital nerve (MPPDN). Ten fresh-frozen cadaveric specimens were analyzed for anatomical variance in the nerve distribution of the MPPDN. In addition, clinical results from a retrospective review of nine patients who underwent surgical nerve decompression of the MPPDN are presented. Significant anatomical variance was found for the MPPDN in the cadaveric dissection of 10 fresh-frozen specimens. Nine patients with a clinical diagnosis of entrapment of the MPPDN all obtained excellent pain relief with surgical external neurolysis. Only one complication occurred: a hypertrophic scar formation that was successfully treated with intralesional steroid injections. The authors believe that this MPPDN entrapment is often overlooked or misdiagnosed as plantar fasciitis. Surgical peripheral nerve decompression of this nerve can provide positive outcomes for patients suffering from midarch foot pain caused by this pain generator.

Comment on IWGDF ulcer prevention guidelines.

The IWGDF 2019 Updated Guidelines for prevention of foot ulcers in diabetes advise that nerve decompression surgery not be considered. This nerve decompression option has similar scientific supporting evidence to other surgeries which are recommended. The sanction ignores a large body of non-Level 1 evidence demonstrating various beneficial outcomes of ND including pain relief, DFU prevention, and protection from recurrence and amputation.

Ultrasound-Guided Proximal and Distal Tarsal Decompression: An Analysis of Pressures in the Tarsal, Medial Plantar, and Lateral Plantar Tunnels.

Objectives. To analyze the reliability of measurements of tarsal tunnel and medial and lateral plantar tunnel pressures before and after ultrasound-guided release. Measurements taken were guided by ultrasound to improve reliability. This novel approach may help surgeons make surgical decisions. The second objective was to confirm that decompression using ultrasound-guided surgery as previously described by the authors is technically effective, reducing pressure to the tarsal and medial and lateral plantar tunnels. Methods. The study included 23 patients with symptoms compatible with idiopathic tarsal tunnel syndrome (TTS). The first step was to measure intracompartmental pressure of the tarsal tunnel, medial plantar tunnel, and lateral plantar tunnel preoperatively. The second step was ultrasound-guided decompression of the tibial nerve and its branches. Subsequently, pressure was measured again immediately after decompression in the 3 tunnels. Results. After surgery, the mean values significantly dropped to normal values. This represents a validation of effective decompression of the tibial nerve and its branches in TTS with ultra-minimally invasive surgery. Conclusions. The ultrasound-guided surgical technique to release the tibial nerve and its branches is effective, significantly reducing pressure in the tunnels and, thereby, decompressing the nerves.Level of evidence: Level IV.

Ultrasound-Guided Decompression of the Intermetatarsal Nerve for Morton's Neuroma: A Novel Closed Surgical Technique.

BACKGROUND: This study describes the technique for decompression of the intermetatarsal nerve in Morton's neuroma by ultrasound-guided surgical resection of the transverse intermetatarsal ligament. This technique is based on the premise that Morton's neuroma is primarily a nerve entrapment disease. As with other ultrasound-guided procedures, we believe that this technique is less traumatic, allowing earlier return to normal activity, with less patient discomfort than with traditional surgical techniques. METHODS: We performed a pilot study on 20 cadavers to ensure that the technique was safe and effective. No neurovascular damage was observed in any of the specimens. In the second phase, ultrasound-guided release of the transverse intermetatarsal ligament was performed on 56 patients through one small (1- to 2-mm) portal using local anesthesia and outpatient surgery. RESULTS: Of the 56 participants, 54 showed significant improvement and two did not improve, requiring further surgery (neurectomy). The postoperative wound was very small (1-2 mm). There were no cases of anesthesia of the interdigital space, and there were no infections. CONCLUSIONS: The ultrasound-guided decompression of intermetatarsal nerve technique for Morton's neuroma by releasing the transverse intermetatarsal ligament is a safe, simple method with minimal morbidity, rapid recovery, and potential advantages over other surgical techniques. Surgical complications are minimal, but it is essential to establish a good indication because other biomechanical alterations to the foot can influence the functional outcome.

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.

Anatomic Delineation of Tarsal Tunnel Innervation via Ultrasonography.

OBJECTIVES: High-resolution ultrasonography (US) can play an important role in studying nerves, as it has several advantages. Entrapments of distal tibial nerve branches can be mapped out or diagnosed with selective anesthetic blocks, and US can guide therapeutic procedures, such as radiofrequency ablation and selective infiltrations of specific nerve branches. The aim of this study was to verify that US is an effective method for accurately locating the posterior tibial nerve and its terminal branches, such as the medial calcaneal branch, the first calcaneal branch, and the medial and lateral plantar nerves. METHODS: In this study, we analyzed the correlation between US mapping and real anatomy after cadaveric dissection, assessing the distribution and variability of the tibial nerve and its terminal branches. We used 12 fresh anatomic specimens of the foot and ankle, including the calf. A high-resolution US study of the tibial nerve and its branches was performed. RESULTS: The results of the US studies of the anatomic specimens were drawn as paper diagrams and in data collection tables. Both were completed twice per anatomic specimen, first using the results of the US study and second using the results from dissection of the anatomic specimens; this approach enabled us to compare the results and verify whether the US study and the dissection correlated on the topography of the tibial nerve and its terminal branches. We found almost total agreement between the US and dissection results, with no significant differences between the evaluations. CONCLUSIONS: On the basis of this work, we can conclude that high-resolution US is almost 100% effective as a tool for identifying the tibial nerve and its branches, enabling the specialist to make diagnoses or perform selective treatments on each nerve branch and even to design surgical interventions by observing the patient's anatomy before performing the dissection.

Small Fiber Neuropathy: Differential Diagnosis and Treatment Implications.

Burning sensation in the feet is a common problem encountered in podiatric medicine. When this pain is bilateral, symmetric, and includes the top and bottom of both feet, small nerve fiber involvement must be considered in the differential diagnosis. With the now available, in-office, skin biopsy quantification of intraepidermal nerve fibers, documentation of the presence of small fiber involvement in the pain mechanism is possible. Technical details of performing the skin biopsy are reviewed and the legal implications of a positive abnormal skin biopsy for intraepidermal nerve fibers is discussed.

Case Study: Osseous Pathology with Peripheral Nerve Entrapment and Neuromata.

This case illustrates the complexity and interrelationship of osseous pathology with peripheral nerve entrapment and neuromata. She had an iatrogenic nerve injury of a branch of the medial dorsal cutaneous nerve causing her painful scar. Secondarily, she developed an injury to her common peroneal nerve from the cast immobilization, resulting in palsy/drop foot. The tarsal tunnel entrapment was likely a sequela of the cast immobilization and chronic swelling. Her postoperative chronic pain was compounded by the failure to use grommets with the polymeric silicon (Silastic) implant at the initial surgery, leading to a breakdown of the implant with subsequent detritic synovitis.

Perioperative posterior heel pain caused by multiple etiologies including a neuroma in continuity of the posterior branch of the sural nerve: a case report.

Posterior heel pain after a prior Haglund's deformity surgical correction can be resultant to multiple etiologies: osseous, tendinous, and neural. In this case report, all three potential etiologies were found to be contributing to the postoperative status of the patient. This case report illustrates identification and treatment of a neuroma in continuity of the posterior branch of the sural nerve with preservation of the sural nerve itself via microdissection, which we believe has not been described previously in the literature.

Reducing the pain of local 1% lidocaine infiltration with a preceding bacteriostatic saline injection: a double-blind prospective trial.

BACKGROUND: Lidocaine injection for local anesthesia is a common podiatric medical procedure. We tested the hypothesis that injection of bacteriostatic saline solution containing 0.9% benzyl alcohol before the lidocaine infiltration can reduce the burning caused by lidocaine injection. METHODS: This double-blind prospective trial involved 45 participants who each received four injections in two areas of the dorsum of the foot and rated the perceived pain on a visual analog scale. The order of the injections was designed to disguise the control and intervention arms of the study. RESULTS: The sensation of the lidocaine injection after the injection of saline was reduced significantly (P = .028). The percentage of lidocaine injections with visual analog scale scores of 0 increased by 36% after preinjection with bacteriostatic saline solution containing 0.9% benzyl alcohol. CONCLUSIONS: The fact that 40% of the intervention visual analog scale pain scores for lidocaine injections were 0 suggests that a near painless lidocaine injection technique is an achievable goal and that the present technique is a simple and inexpensive method of reducing the pain of lidocaine injections.

Endoscopic plantar fasciotomy: preliminary study with cadaveric specimens. 1991.

The authors have developed an endoscopic approach to a plantar fasciotomy. This technique would minimize the surgical trauma that is normally induced with a conventional type of heel spur surgery. The authors believe that this new technique will provide an earlier return to normal ambulation, less loss of work, and earlier, overall increased patient comfort.

Contralateral peak plantar pressures with a postoperative boot: a preliminary study.

BACKGROUND: Frequent use of walking boots in podiatric medicine often elicits patient complaints and sequelae from the imposed limb-length discrepancy. This study was designed primarily to determine whether peak plantar pressures are decreased in the contralateral foot when a moderately worn athletic shoe is worn opposite a high-calf walking boot and, if so, secondarily to determine whether a specialized surgical shoe worn on the contralateral foot can also effectively reduce this pressure. The pressure reductions were then compared to determine whether significantly greater plantar pressure reduction was provided by either the athletic shoe or the surgical shoe. METHODS: Participants without a foot abnormality walked on a treadmill in four footwear combinations: barefoot bilaterally, high-calf rocker-bottom sole (HCRB) walking boot/ barefoot, HCRB walking boot/athletic shoe, and HCRB walking boot/modified walking boot shoe. Measurements were taken with the participants wearing socks. Peak plantar calcaneal pressures were collected. RESULTS: Peak plantar pressures under the calcaneus opposite the HCRB walking boot were significantly reduced from barefoot pressures when either an athletic shoe or the modified walking boot shoe was worn. However, no significant difference was seen when comparing the reduction by the athletic shoe with that by the modified walking boot. CONCLUSIONS: Wearing an athletic shoe on the foot opposite an HCRB walking boot reduces calcaneal pressures; however, wearing a modified device with structural properties of an HCRB walking boot sole is no better than an athletic shoe at reducing peak calcaneal pressures.

Historical development of bipolar coagulation.

In 1926, a physicist at Harvard named William T. Bovie created an instrument, which revolutionized the medical profession--the unipolar electrocautery device. This incredible device could make surgical incisions and provide hemostasis as well. It came with a price, however, as it also created new risks and dangers in the operating room, such as electrical burns and fires. To resolve some of these problems, a bipolar electrocautery device was developed. The historical development and principles of both unipolar and bipolar electrocautery will be discussed in this article.

Computerized analysis of plantar pressure variation in flip-flops, athletic shoes, and bare feet.

BACKGROUND: High peak plantar pressures predispose to foot problems and may exacerbate existing conditions. For podiatric physicians to make educated recommendations to their patients, it is important and necessary to begin to look at different shoes and how they affect peak plantar pressure. METHODS: To determine how flip-flops change peak plantar pressure while walking, we compared peak plantar pressures in the same test subjects wearing flip-flops, wearing athletic shoes, and in bare feet. Ten women with size 7 feet and a body mass index less than 25 kg/m2 were tested with an in-shoe pressure-measurement system. These data were collected and analyzed by one-way analysis of variance and computer software. RESULTS: Statistically significant results were obtained for nine of the 18 comparisons. In each of these comparisons, flip-flops always demonstrated higher peak plantar pressures than athletic shoes but lower pressures than bare feet. CONCLUSION: Although these data demonstrate that flip-flops have a minor protective role as a shock absorber during the gait cycle compared with pressures measured while barefoot, compared with athletic shoes, they increase peak plantar pressures, placing the foot at greater risk for pathologic abnormalities.

The use of low-energy radial shockwave in the treatment of entrapment neuropathy of the medial calcaneal nerve: a pilot study.

Medial calcaneal nerve entrapment is a well-recognized cause of heel pain. In addition, the development of an amputation neuroma of the medial calcaneal nerve from prior heel surgery via an open incision on the medial aspect of the heel is a serious common postoperative complication and can be extremely difficult to treat. This preliminary pilot study demonstrates that the use of low-energy extracorporeal shockwave is safe and efficacious in the treatment of this disorder without the morbidity associated with denervation surgery, which would be one of the most common methods to treat this complicated situation. Four patients, 2 with bilateral affectation, for a total of 6 medial calcaneal nerves, had a series of treatments with low-energy radial shockwave with the Swiss DolorClast machine. All 4 patients had improvement in their pain scores, to the point that none elected surgical treatment, and there were no complications.

Endoscopic nerve decompression.

Endoscopic decompression for forefoot nerve entrapments is discussed in this article from not only the perspective of preoperative indications, intraoperative technique, and postoperative management, but with reference to the changing paradigm for management of this condition. Surgical results are discussed and compared with other published reports. Complications of the surgical technique are also discussed, which will give the operating surgeon a frame of reference when comparing decompression procedures to those techniques involving nerve resection. There is also a valuable discussion of current methods of diagnosis that may help the practitioner improve patient outcomes.

Superficial peroneal nerve (superficial fibularis nerve): the clinical implications of anatomic variability.

The purpose of this study is to refine further the knowledge about the anatomic variability of the superficial peroneal nerve in the middle third of the leg. Approaching the superficial peroneal nerve in this location is required: 1) when either the deep or the superficial peroneal nerve must be resected for the treatment of dorsal foot pain; 2) when a neurolysis of the superficial peroneal nerve is required; 3) when a fasciotomy must be performed either for trauma or for exertional compartment syndrome surgery; and 4) during elevation of a fasciocutaneous or fibular flaps. Because of the variability encountered during these procedures, a prospective study was carried out via lower extremity cadaver dissection with fresh, frozen specimens. A total of 35 nonpaired lower extremities and 40 paired lower extremities were dissected with 3.5 loupe magnification. The superficial peroneal nerve was identified in the lateral compartment immediately adjacent to the fascial septum in 72% of the specimens (54 of 75), with a branch in both the anterior and the lateral compartment in 5% of the specimens (4 of 75), and located in the anterior compartment in only 23% of the specimens (17 of 75). The clinical implications of these anatomic findings are that the surgeon operating in the anterior and lateral compartments of the leg should be aware that the superficial peroneal nerve may be located in the lateral compartment and may also exhibit branches in both the anterior and lateral compartments.