Cutaneous innervation of the medial ankle: an anatomic study of the saphenous, sural, and tibial nerves and their clinical significance

Anesthesia for the Patient Undergoing Foot and Ankle Surgery

Modern anesthetic management for foot and ankle surgery includes a variety of anesthesia techniques including general anesthesia, neuraxial anesthesia, or MAC in combination with peripheral nerve blocks and/or multimodal analgesic agents. The choice of techniques should be tailored to the nature of the procedure, patient comorbidities, anesthesiologist skill level, intensity of anticipated postoperative pain, and surgeon preference.

Anesthesia for the Patient Undergoing Foot and Ankle Surgery

Modern anesthetic management for foot and ankle surgery includes a variety of anesthesia techniques including general anesthesia, neuraxial anesthesia, or MAC in combination with peripheral nerve blocks and/or multimodal analgesic agents. The choice of techniques should be tailored to the nature of the procedure, patient comorbidities, anesthesiologist skill level, intensity of anticipated postoperative pain, and surgeon preference.

Nerve Ablation in the Foot and Ankle

Ablation therapies in the foot and ankle are accessible adjuncts to surgery and comprehensive pain management in recalcitrant pain syndromes. Techniques are best applied to individual patient anatomy with strong advantages in a working knowledge of neuromuscular real-time imaging with ultrasound. Interventionists face the unique challenge in this region of preserving balance and proprioception as well as intrinsic muscle function, while optimizing pain relief. A decision-making approach emphasizing selectivity by using regional and target-specific ablations is optimal. This article reviews basic technique, approaches, potential complications, and ultrasound anatomy for a practical introduction to ablation options in the foot and ankle.

Peripheral Nerve Blocks in Foot and Ankle Surgery

Postoperative pain is one of the most important factors in regard to patient outcomes. It has been linked with patient satisfaction, length of stay, and overall hospital costs. Peripheral nerve blocks have provided a safe, effective method to control early postoperative pain when symptoms are most severe. Peripheral nerve blocks, whether used intraoperatively or postoperatively, provide an alternative or adjunct to conventional pain management methods for patients who may not tolerate heavy narcotics or general anesthesia, in particular the elderly and those with cardiopulmonary disease.

A Randomized Controlled Trial Assessing the Effect of a Continuous Subcutaneous Infusion of Local Anesthetic Following Elective Surgery to the Great Toe

Local anesthetic use for wound infusions, single injection, and continuous nerve blocks for postoperative analgesia is well established. No study has investigated the effect of a continuous block of the saphenous and superficial peroneal nerves at the level of the ankle joint following first ray surgery. A double blind randomized controlled trial was designed. One hundred patients with hallux valgus and rigidus requiring surgical correction were recruited and randomized to receive a postoperative continuous infusion at the ankle of normal saline or ropivacaine for 24 hours. Pain scores were recorded on postoperative days 1 and 7. There were more females than males. Follow-up was 100%. There were no significant differences in demographic data between the 2 randomized groups. There was no significant difference between the absolute visual analog scale scores on day 1 (P = .14) and day 7 (P = .16); nor was there a significant difference in reduction in scores between days 1 and 7 (P = .70). This study has shown no benefit to postoperative analgesia with the use of a continuous infusion of ropivacaine at the ankle. We, therefore, cannot currently recommend its use in the way described. Further studies may still identify a role for continuous local anesthetic infusions at the ankle to improve postoperative analgesia.

LEVELS OF EVIDENCE

Level I : Prospective randomised control trial.

Tarsal tunnel syndrome masked by painful diabetic polyneuropathy

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The real cause of symptoms in patients with neuropathy may not be related with diabetes.

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It is essential to investigate the etiology of the disease with more localized pathologies in such complicated cases.

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Tarsal tunnel syndrome gives a more segmental clinical profile with nerve entrapment.

Introduction

Various causes influence the etiology of tarsal tunnel syndrome including systemic diseases with progressive neuropathy, such as diabetes.

Presentation of case

We describe a 52-year-old male patient with complaints of numbness, burning sensation and pain in both feet. The laboratory results showed that the patient had uncontrolled diabetes, and the EMG showed distal symmetrical sensory-motor neuropathy and nerve entrapment at the right. Ultrasonography and MRI showed the cyst in relation to medial plantar nerve, and edema- moderate atrophy were observed at the distal muscles of the foot.

Discussion

Foot neuropathy in diabetic patients is a complex process. So, in planning the initial treatment, medical or surgical therapy is selected based on the location and type of the pathology. Foot deformities can be corrected with resting, anti-inflammatory treatment, appropriate shoes, orthesis and socks, and if required, ankle stabilization can be attempted. If the patient is still unresponsive, surgical treatment may be applied.

Conclusion

It is essential to investigate more localized reasons like tarsal tunnel syndrome that may mimic diabetic neuropathy, should be treated primarily.

The saphenous nerve in foot and ankle surgery: its variable anatomy and relevance

BACKGROUND

Several studies have raised doubt regarding the role of the saphenous nerve (SN) in the foot, and some authors omit the SN from ankle blocks. Our aim was to assess the SN anatomy with reference to foot and ankle surgery.

METHODS

In 29 cadaveric feet the SN was traced to its termination. At the ankle, the distances from the SN to the tibialis anterior tendon (TAT) and the long saphenous vein (LSV) were recorded.

RESULTS

In 24 specimens, a SN was present at the ankle, and in 19 specimens extended to the foot. The mean distances from the nerve to the TAT and LSV were 15 mm and 4mm respectively. The nerve reached the first metatarsal (MT) in 28% of specimens.

CONCLUSION

Although the SN anatomy is less extensive than previously described, it often reaches the first MT and therefore should routinely be included in ankle blocks for forefoot surgery.

Heel neuroma: a case study

This article reviews the diagnosis, pathology, and treatment of plantar heel neuroma, an entity that has previously been described and recognized, yet one that we feel warrants further review because of the prevalence of plantar heel pain that does not respond to the usual array of treatments. We feel that neuroma of the medial calcaneal nerve often goes undiagnosed, and may progress to a severely painful condition that requires surgical intervention. In this article, we describe another case of heel neuroma in an otherwise healthy patient with a history of chronic plantar heel pain that was unresponsive to a wide array of nonsurgical treatments.

LEVEL OF CLINICAL EVIDENCE

4.

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.

Hindfoot endoscopy

Hindfoot pain can be caused by a variety of pathologies; most of these can be diagnosed and treated by means of endoscopy. The main indications are posterior tibial tenosynovectomy, diagnosis of a peroneus brevis length rupture, peroneal tendon athesiolysis, flexor hallucis longus release, os trigonum removal, endoscopic treatment for retrocalcaneal bursitis, endoscopic treatment for Achilles (peri)tendinopathy, and treatment of ankle joint or subtalar joint pathology. The advantages of endoscopic hindfoot surgery over open surgery are less morbidity, reduction of postoperative pain, outpatient treatment, and functional postoperative treatment. This two-portal hindfoot endoscopy approach is a safe, reliable, and exciting method to diagnose and treat a variety of posterior ankle problems and offers a good alternative to open surgery.

Variations in the origin of the medial and inferior calcaneal nerves

INTRODUCTION

Entrapment of the medial heel region nerves is often mentioned as a possible cause of heel pain. Some authors have suggested that the medial and inferior calcaneal nerves may be involved in such heel pain, including plantar fasciitis, heel pain syndrome and fat pad disorders. The aim of this study was to give a detailed description of the medial heel that would determine the variability and pattern of the medial and inferior calcaneal nerves, as well as to relate these findings to the currently used incision line for tarsal tunnel, fixations of fractures with external nailing, medial displacement osteotomy and nerve blocks in podiatric medicine.

MATERIALS AND METHODS

The origin, relationship, distribution, variability and innervation of medial and inferior calcaneal nerves were studied with the use of a 3.5 power loupe magnification for dissection of 25 adult male feet of formalin-fixed cadavers. The medial heel was found to be innervated by just one medial calcaneal nerve in 38% of the feet, by two medial calcaneal nerves in 46%, by three medial calcaneal nerves in 12% and by four medial calcaneal nerves in 4%. An origin for a medial calcaneal nerve from the medial plantar nerve was found in 46% of the feet. This nerve most often innervates the skin of the posteromedial arch.

RESULTS

In our dissection, the rate of occurrence of the medial and inferior calcaneal nerves in medial heel region was 100%. When compared with the inferior calcaneal nerve, the medial calcaneal nerve was posterior, superior and thicker. The inferior calcaneal nerve supplies deeper structures. In the majority of the cases, inferior calcaneal nerve aroused from the lateral plantar nerve, but it may also arise from the tibial nerve, sometimes in a common origin with the medial calcaneal nerve.

CONCLUSIONS

Knowledge of fine anatomy of the calcaneal nerves is necessary to ensure safe surgical intervention in the medial heel region.

Nerve entrapments of the lower leg, ankle and foot in sport

Exercise-related leg pain is a common and yet difficult management problem in sports medicine. There are many common causes of such symptoms including stress fractures and muscle compartment syndromes. There are also a number of less common but important conditions including popliteal artery entrapment and nerve entrapment syndromes. Even for an astute clinician, distinction between the different medical causes may be difficult given that many of their presenting features overlap. This review highlights the common clinical presentations and raises a regional approach to the diagnosis of the neurogenic symptoms. In part, this overlapping presentation of different pathological conditions may be due to a common aetiological basis of many of these conditions namely, fascial dysfunction. The same fascial restriction that predisposes to muscle compartment syndromes may also envelop the neurovascular structures within the leg resulting in either ischaemic or neurogenic symptoms. For many athletes with chronic exercise-related leg pain, combinations of such problems often coexist suggesting a more widespread fascial pathology. In our clinical experience, we often label such patients as 'fasciopaths'; however, the precise pathophysiological basis of this fascial problem remains to be elucidated. This review discusses the various nerve entrapment syndromes in the lower limb that may result in exercise-related leg pain in the sporting context. The anatomy, clinical presentation, investigation, medical management and surgical treatment are discussed at length for each of the syndromes. It is clear from clinical experience that the outcome of surgical management of such syndromes fares much better where a clear dermatomal pain distribution is present or where focal weakness and/or sensory symptoms appropriate for the nerve are present. In many situations, however, nonspecific leg pain or vague nonlocalising sensory symptoms are present and in such situations, alternative diagnoses must be considered and investigated appropriately. As mentioned above, many different pathologies may coexist in the lower limb and may be a source of confusion for the clinician or alternatively may be the reason for poor treatment outcomes.

Neuromas of the calcaneal nerves

A neuroma of a calcaneal nerve has never been reported. A series of 15 patients with heel pain due to a neuroma of a calcaneal nerve are reviewed. These patients previously had either a plantar fasciotomy (n = 4), calcaneal spur removal (n = 2), ankle fusion (n = 2), or tarsal tunnel decompression (n = 7). Neuromas occurred on calcaneal branches that arose from either the posterior tibial nerve (n = 1), lateral plantar nerve (n = 1), the medial plantar nerve (n = 9), or more than one of these nerves (n = 4). Operative approach was through an extended tarsal tunnel incision to permit identification of all calcaneal nerves. The neuroma was resected and implanted into the flexor hallucis longus muscle. Excellent relief of pain occurred in 60%, and good relief in 33%. One patient (17%) had no improvement and required resection of the lateral plantar nerve. Awareness that the heel may be innervated by multiple calcaneal branches suggests that surgery for heel pain of neural origin employ a surgical approach that permits identification of all possible calcaneal branches.