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Compression and irritation at the plantar aspect of the transverse intermetatarsal ligament may lead to a compressive neuropathy called Morton’s neuroma. There are many treatment options for Morton’s neuroma, with the most common surgical option being traction neurectomy. While there has been success in many surgical procedures, up to 35% of patients treated with traction neurectomy have recurrent pain and up to one-third of these patients have a recurrent stump neuroma. These neuromas are caused by abnormal axonal growth during regeneration, leading to an unorganized mass of fibrotic collagenous tissues, Schwann cells, and axons. More recent surgical treatments of neuromas have included nerve capping, which has been proposed to prevent painful neuroma formation by isolating the nerve end from external chemosignaling and reducing disorganized axonal outgrowth. An off-the-shelf, biocompatible porcine small intestine submucosa (pSIS) derived nerve cap with internal chambering has been investigated in a rodent study, which showed less pain sensitivity and less axonal swirling indicative of reduced likelihood of neuroma formation. Furthermore, a recent clinical study indicated that patients experienced a significant reduction in pain 3 months after Morton’s neuroma excision followed by repair using a nerve cap. This article describes the surgical technique of the aforementioned clinical study to mitigate neuroma formation, where a Morton’s neuroma is excised, and the remaining proximal nerve stump is inserted within a nerve cap and buried in the surrounding muscle. Level of Evidence: Level V: Expert opinion

Background Despite multiple surgical modalities available for the management of Morton’s neuroma, complications remain common. Targeted muscle reinnervation (TMR) has yet to be explored as an option for the prevention of recurrence of Morton’s neuroma. The purpose of the present investigation was to determine the consistency of the relevant foot neurovascular and muscle anatomy and to demonstrate the feasibility of TMR as an option for Morton’s neuroma. Methods The anatomy of 5 fresh-tissue donor cadaver feet was studied, including the course and location of the medial and lateral plantar nerves (MPNs and LPNs), motor branches to abductor hallucis (AH) and flexor digitorum brevis (FDB), as well as the course of sensory plantar digital nerves. Measurements for the locations of the muscular and sensory branches were taken relative to landmarks including the navicular tuberosity (NT), AH, FDB, and the third metatarsophalangeal joint (third MTPJ). Results The mean number of nerve branches to FDB identified was 2. These branch points occurred at an average of 8.6 cm down the MPN or LPN, 9.0 cm from the third MTPJ, 3.0 cm distal to AH distal edge, and 4.8 cm from the NT. The mean number of nerves to AH was 2.2. These branch points occurred at an average of 6.3 cm down the MPN, 11.9 cm from the third MTPJ, 0.8 cm from the AH distal edge, and 3.8 cm from the NT. Conclusions Recurrent interdigital neuroma, painful scar, and neuropathic pain are common complications of operative management for Morton’s neuroma. Targeted muscle reinnervation is a technique that has demonstrated efficacy for the prevention and treatment of neuroma, neuropathic pain, and phantom limb pain in amputees. Herein, we have described the neuromuscular anatomy for the application of TMR for the management of Morton’s neuroma. Target muscles, including the AH and FDB, have consistent innervation patterns in the foot, and consequently, TMR represents a viable option to consider for the management of recalcitrant Morton’s neuroma. Levels of Evidence: V

Background Although the precise pathoetiology of Morton’s neuroma remains unclear, chronic nerve entrapment from the overlying intermetatarsal ligament (IML) may play a role. Traditional operative management entails neuroma excision but risks unpredictable formation of stump neuroma. Materials and methods Medical records were examined for adult patients who failed at least 3 months of conservative treatment for symptomatic and recalcitrant Morton’s neuroma and who then underwent isolated IML decompression without neuroma resection. Results A total of 12 patients underwent isolated IML decompression for Morton’s neuroma with an average follow-up of 13.5 months. Visual Analog Pain Scale averaged 6.4 ± 1.8 (4-9) preoperatively and decreased to an average of 2 ± 2.1 (0-7) at final follow-up (P = .002). All patients reported significant improvement. Conclusion Isolated IML release of chronically symptomatic Morton’s neuroma shows promising short-term results regarding pain relief, with no demonstrated risk of recurrent neuroma formation, permanent numbness, or postoperative symptom exacerbation. Level of Evidence: Level IV: Case series

Background: When using a dorsal approach for Morton’s neuroma excision, the most common complication is recurrent Morton’s neuroma. The present cadaveric study demonstrates how far proximally the nerve is resected during a dorsal approach and examines both the laminar spreader and Gelpiretractor to determine which instrument facilitates maximal proximal resection of the nerve. Methods: This study involved 12 fresh-frozen cadaver specimens, each of which underwent a dorsal approach to the interdigital nerve with proximal resection. Either a laminar spreader or a Gelpi retractor was used to improve visualization of the intermetatarsal space. The interdigital nerve was then resected, and the lengths of the cut nerves were compared based on the retractor employed. Results: The mean length of proximal resection in the second intermetatarsal space was 2.42 cm when using the laminar spreader and 1.93 cm when using the Gelpi retractor (P = .252). In the third intermetatarsal space, the mean length of proximal resection was 2.14 cm when using the Laminar spreader and 1.48 cm when using the Gelpi retractor (P = .166). Conclusion: This study demonstrates how far proximal the interdigital nerve is resected during a dorsal approach to Morton’s neuroma and shows no statistically significant difference between the Laminar spreader and the Gelpi retractor. Levels of Evidence: Level V: Cadaver study

Background. Morton’s neuroma is a common cause of forefoot pain. Outcomes of conservative therapy are mixed and many patients undergo operative intervention. Radiofrequency ablation has recently gained favor as a treatment option, although the optimal regime is unknown. This study investigates the effectiveness of 2 versus 3 cycles of radiofrequency ablation for the treatment of Morton’s neuroma. Methods. We surveyed a cohort of patients with Morton’s neuroma who had progressed to radiofrequency ablation after failed conservative treatment. Patients received either 2 or 3 cycles of radiofrequency ablation by a single surgeon. We assessed patients based on their change in numerical pain rating scale, symptom improvement, complications, and progression to surgical excision through a series of telephone interviews. Outcomes between the 2 treatment arms were compared by parametric tests. Results. Twenty-eight patients were included in the study. Eighteen patients with 21 neuromas received 2 cycles and 10 patients with 11 neuromas received 3 cycles. Mean time of follow-up was 12.9 months. Overall, 88% of patients were either very or moderately satisfied with their outcome. In patients who received 2 cycles mean numerical pain scores decreased from 7.9 ± 1.1 to 3.4 ± 2.4 postprocedure. Three patients progressed to operative excision. In patients who received 3 cycles, numerical pain scores decreased from 8.0 ± 1.0 to 1.5 ± 2.0 postprocedure. One patient progressed to operative excision. Patients who received 3 cycles had reduced medium-term pain postoperatively compared with 2 cycles (3.4 ± 2.4 vs 1.5 ± 2.0, P = .011). Conclusion. Radiofrequency ablation provides a high rate of patient satisfaction in the treatment of Morton’s neuroma with few side effects. It appears that 3 cycles may be superior to 2 cycles but a randomized controlled trial will be required to confirm these results. Levels of Evidence: Intervention, Level III: Comparative study without concurrent controls

Background. Interdigital neuroma (IN), otherwise known as Morton’s neuroma, is a common cause of metatarsalgia presenting to the elective foot and ankle clinic. Surgical excision of the IN in patients who fail to respond to nonoperative measures is considered to be the gold standard of care in many centers. The Royal College of Pathologists UK recommend that all excised interdigital Morton’s neuromas are sent for formal histopathological analysis. We present a study correlating clinical and radiological diagnosis with histopathologic appearances of IN following surgical excision, and question if routine histopathological analysis is warranted. Methods. A retrospective study was carried out in a single center. Ninety-six operative records were reviewed to identify all the cases of IN surgically resected between January 2007 and July 2016. The histopathology result of the resected IN specimen, that had a clinical and radiological diagnosis of IN, was analyzed. Results. A total of 85 patients met the inclusion criteria and were included in the final analysis. We found that 100% of patients with a clinical, radiographic, and intraoperative diagnosis of a Morton’s neuroma had a histopathological report confirming a Morton’s interdigital neuroma. Conclusion. In our single-surgeon series, histopathologic diagnosis is in complete agreement with clinical and radiological diagnosis. We therefore recommend that routine histopathological analysis of IN is not necessary, saving resources and providing a cost benefit. Histopathologic examination should be reserved only in cases where intraoperative findings do not concur with clinical and radiological features. Levels of Evidence: Level IV: Case series

Background. Operative procedures are indicated in the treatment of Morton’s neuroma (MN) when conservative therapies have been unsuccessful. A dorsal approach for neurolysis or neurectomy was strongly recommended. The aim of this case series study was to prospectively analyze the midterm clinical outcome and complications following the excision of a MN using a plantar longitudinal approach. Methods. Between September 2000 and January 2009, we included 44 patients (51 feet, 56 neuromas) in a prospective study treated by excision of a primary MN using a plantar longitudinal approach. The MN diagnosis was based on clinical symptoms, magnetic resonance imaging findings, and pain relief after infiltration of local anesthetics. Histological examinations were performed in all resected specimens. The patients returned for final follow-up at a mean of 54 (range = 12 to 99) months, comparing preoperative and postoperative perception of pain on a Visual Analogue Scale (VAS) and assessing clinical findings. Results. The average amount of pain, according to VAS, was 8 (range = 6-9) points preoperatively and 0.4 (range = 0-5) points at final follow-up. Complications occurred in 7.1% of interventions and scar problems in 5.2%, including delayed wound healing, hypertrophic scar formation, and inclusion cyst. Conclusion. The present study shows a strong relief of pain after MN resection using a plantar longitudinal incision, coupled with a low rate of local complications. This surgical procedure seems to be a reliable choice for the excision of MN, even in cases with MN in adjacent webspaces, because it is technically simple and the plantar scar is not bothersome if properly located. Levels of Evidence: Therapeutic, Level IV: Prospective, Case series

Morton’s neuroma is a common condition mainly affecting middle aged women, and there are many proposed etiological theories involving chronic repetitive trauma, ischemia, entrapment, and intermetatarsal bursitis. Incorrect terminology suggests that the underlying pathological process is a nerve tumor, although histological examination reveals the presence of inflammatory tissue—that is, perineural fibrosis. The common digital nerve and its branches in the third planter webspace are most commonly affected. Diagnosis is usually made through history taking and clinical examination but may be aided by ultrasonography and magnetic resonance imaging. Current nonoperative treatment strategies include shoe-wear modifications, custom made orthoses, and injections of local anesthetic agents, sclerosing agents, and steroids. Operative management options primarily involve either nerve decompression or neurectomy. We have reviewed the published literature to evaluate the outcomes of the available diagnostic modalities and treatment options and present an algorithm for clinical practice.