Dorsal suspension for Morton's neuroma: A comparison with neurectomy

The comparison of postoperative outcomes in Morton's neuroma excision between plantar versus dorsal approach: A systematic review and meta-analysis

BACKGROUND

Current literature lacks comprehensive information comparing the clinical outcomes of plantar and dorsal approaches for Civinini-Morton syndrome, also known as Morton's neuroma. This systematic review and meta-analysis was conducted to evaluate and compare the clinical outcomes of neurectomy for Morton's neuroma, focusing on the differences between the plantar and dorsal approach.

METHODS

Our comprehensive literature review adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and utilized databases including PubMed, Embase, Web of Science, and the Cochrane Library. Data investigated in this study included postoperative sensory loss, scar tenderness, reoperation, histopathology, complications, pain score, patient satisfaction, functional scores, and time to weight bearing.

RESULTS

Total eight studies were included in this study. In aggregate, 237 neuromas underwent excision using the plantar approach, while 312 neuromas were treated via the dorsal approach. A significantly higher rate of postoperative reduced sensory was found in the dorsal group: 48.5 % (64/132) Vs. 62.0 % (80/129) with the relative ratio (RR) of 0.79 (95 % CI, 0.64-0.97). A significantly higher rate of postoperative scar tenderness was noted in the plantar group: 16.7 % (32/192) Vs. 6.2 % (14/225) with the RR of 2.27 (95 % CI, 1.28-4.04). Regarding the histopathology, 99.3 % (143/144) and 97.1 % (134/138) accuracy rate was confirmed in the plantar approach and dorsal approach, respectively, with the RR of 1.02 (95 % CI, 0.98-1.07). Overall reoperations and complications were not different between groups at 5.3 % (10/189) and 8.8 % (19/216) in the plantar group versus 6.1 % and 12.0 % (35/291) in dorsal group.

CONCLUSIONS

We recommend detailed discussions with patients prior to surgery to weigh the advantages and disadvantages of each approach.

Operative treatment options for Morton's neuroma other than neurectomy - a systematic review

BACKGROUND

The effectiveness of operative treatments other than neurectomy for Morton's neuroma remains debatable despite several reported studies. This review aimed to evaluate the effects of operative treatments for Morton's neuroma other than neurectomy using an algorithmic approach and a structured critical framework to assess the methodological quality of reported studies.

METHODS

Several electronic databases were searched for articles published until August 2021 that evaluated the outcomes of operative treatments other than neurectomy in patients diagnosed with Morton's neuroma. Data searches, extraction, analysis, and quality assessments were performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, and the clinical outcomes were evaluated using objective, subjective, and negative outcomes; complications; and reoperation rate and type.

RESULTS

After reviewing 11,213 studies, 22 studies were finally included. Although a number of studies with high level of evidence are limited, we divided them according to four categories: (1) neurolysis with or without nerve transposition, (2) minimally invasive nerve decompression, (3) metatarsal osteotomy, and (4) additional procedures after nerve transection or neurectomy. All categories showed reliable outcomes except minimally invasive nerve decompression. The proportion of postoperative neurogenic symptoms was lower with neurolysis than with neurectomy.

CONCLUSION

Whether the alternative procedures were superior to neurectomy remains unclear as the number of good quality studies was limited. The proportion of postoperative neurogenic symptoms was lower with neurolysis than with neurectomy. Furthermore, performing simultaneous dorsal transposition of the nerve along with neurolysis is more recommended than neurolysis alone. Surgeons should be more careful with minimally invasive deep transverse intermetatarsal ligament release and metatarsal shortening osteotomy as their effectiveness remains inconclusive. Finally, we strongly recommend performing intramuscular embedding or intermuscular transposition of the nerve cutting end if neurectomy or nerve transection is inevitable.

LEVEL OF EVIDENCE

Level III, systematic review.

"The Feasibility of Targeted Muscle Reinnervation for the Management of Morton's Neuroma"

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.

Ultrasound-guided Injection Treatments versus Surgical Neurectomy for Morton Neuroma: A Cost-effectiveness Analysis

Background: Morton neuroma is a common, painful disorder of the foot with multiple treatment options of varying cost and effectiveness. Objective: The aim of this study was to determine the most cost-effective treatment pathway for symptomatic Morton neuromas that have failed conservative management. Methods: An incremental cost-utility analysis was performed comparing a direct to surgical neurectomy strategy with three injection selective strategies in which one or more ultrasound-guided injection therapies was tried first prior to surgery for non-responders. The three injection selective strategies included: (1) steroid selective (2) alcohol selective, and (3) steroid/alcohol selective in which both steroid injections and alcohol sclerosing injections were trialed successively prior to surgical neurectomy. The direct to surgery approach was compared with the three different injection selective strategies, and with a no-treatment strategy, in a decision-analytic model for a hypothetical group of patients with symptomatic Morton neuromas that had failed conservative management. Model parameters including treatment costs, effectiveness, complication rates, and health utility states were estimated from the literature, reimbursement databases, and expert opinion. The outcome was cost per quality adjusted life year (QALY) with a time horizon of three years. A societal cost perspective was adopted with a willingness to pay threshold of $100,000 per QALY. Sensitivity analyses for key model parameters were performed. Results: For the base input values, the steroid/alcohol selective strategy was dominant and yielded an incremental cost-effectiveness ratio of $4401/QALY compared to no treatment. The probabilistic sensitivity analysis supported this strategy in 74% of 10,000 simulated trials. Results were robust with low sensitivity to most input parameters. However, when the probability of successful alcohol injection treatment dropped below 40%, the steroid selective strategy became most cost-effective. Conclusion: A trial of ultrasound-guided injection therapies for Morton neuroma is a cost-effective strategy compared to proceeding directly to surgical neurectomy. Clinical Impact: Ultrasound-guided injection therapies are indicated as a first line treatment for patients with symptomatic Morton neuromas that have failed conservative management.

Minimally invasive neurectomy for Morton's neuroma with interdigital approach. Long term results

BACKGROUND

"Morton's Neuroma" is a frequent cause of chronic forefoot pain. It can affect general population, including athletes, and can lead to progressive foot pain and discomfort for daily life activities and sports.

HYPOTHESIS/PURPOSE

Our objective is to evaluate the long-term results in a series of 85 feet, operatively treated with minimally invasive interdigital approach for neurectomy.

STUDY DESIGN

Case series.

METHOD

83 patients (85 feet) were treated between January 2003 and December 2019. The AOFAS score and VAS scale were used to evaluate the patients pre and postoperatively. Results were analyzed using the JASP software.

RESULTS

Mean age was 50.58 years (range 23-77). Eleven (11) were men, and seventy-four (74) women, with two bilateral cases. Mean follow up was 49 months. Our series was evaluated with AOFAS and VAS scores, both showing statistically significant improvement posterior to the operative procedure.

CONCLUSIONS

A series of 85 feet operatively treated for Morton's neuroma with minimally invasive interdigital approach for neurectomy is presented. Long term results were similar to other published series with different approaches, with the advantage of minimal incision, minimum soft tissue dissection and no need to release intermetatarsal ligament, immediate weightbearing and quick return to daily activities and sports. It is concluded that minimally invasive neurectomy with interdigital approach is a safe procedure for Morton's neuroma treatment with similar results that other operative procedures.

LEVEL EVIDENCE

Level IV.

Treating Morton's neuroma by injection, neurolysis, or neurectomy: a systematic review and meta-analysis of pain and satisfaction outcomes

BACKGROUND

Individual evidence suggests that multiple modalities can be used to treat entrapment pathology by Morton's neuroma, including injection, neurolysis, and neurectomy. However, their impacts on patient pain and satisfaction have yet to be fully defined or elucidated. Correspondingly, our aim was to pool systematically identified metadata and substantiate the impact of these different modalities in treating Morton's neuroma with respect to these outcomes.

METHODS

Searches of 7 electronic databases from inception to October 2019 were conducted following PRISMA guidelines. Articles were screened against pre-specified criteria. The incidences of outcomes were extracted and pooled by random-effects meta-analysis of proportions.

RESULTS

A total of 35 articles satisfied all criteria, reporting a total of 2998 patients with Morton's neuroma managed by one of the three modalities. Incidence of complete pain relief after injection (43%; 95% CI, 23-64%) was significantly lower than neurolysis (68%; 95% CI, 51-84%) and neurectomy (74%; 95% CI, 66-82%) (P = 0.02). Incidence of complete satisfaction after injection (35%; 95% CI, 21-50%) was significantly lower than neurolysis (63%; 95% CI, 50-74%) and neurectomy (57%; 95% CI, 47-67%) (P < 0.01). The need to proceed to further surgery was significantly greater following injection (15%; 95% CI, 9-23%) versus neurolysis (2%; 95% CI, 0-4%) or neurectomy (5%; 95% CI, 3-7%) (P < 0.01). Incidence of procedural complications did not differ between modalities (P = 0.30).

CONCLUSIONS

Although all interventions demonstrated favorable procedural complication incidences, surgical interventions by either neurolysis or neurectomy appear to trend towards greater incidences of complete pain relief and complete patient satisfaction outcomes compared to injection treatment. The optimal decision-making algorithm for treatment for Morton's neuroma should incorporate these findings to better form and meet the expectations of patients.

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.

Revision of Recurrent Neuromas

Forefoot neuromas are a common pathology that is seen in a wide variety of patients. Although conservative treatment is successful with modification of shoes/inserts or injections, surgical intervention is occasionally needed to alleviate the discomfort. Most surgical procedures for neuromas have a good outcome. There are times when the outcome is not optimal and revision surgery may be needed. This article describes revision surgery techniques that may lead to an improved outcome. Also discussed is the opportunity to reduce recurrence through the understanding of neuroma biology, diagnosis, and treatment options.