Diagnostic Accuracy of Clinical Tests for Morton's Neuroma Compared with Ultrasonography
Devendra Mahadevan, FRCS (Tr&Orth)email, Muralidharan Venkatesan, MRCS, Raj Bhatt, FRCR, Maneesh Bhatia, FRCS (Tr&Orth) The Journal of Foot and Ankle Surgery; Articles in Press
The accuracy of ultrasonography and magnetic resonance imaging for the diagnosis of Morton's neuroma: a systematic review
Z. Xuc, X. Duanc, X. Yu, H. Wang, X. Dong, Z. Xiang Clinical Radiology; Articles in Press
Correlation of Clinical, Operative, and Histopathologic Diagnosis of Interdigital Neuroma and the Cost of Routine Diagnosis
Kathryn M. O’Connor, Jeffrey E. Johnson, Jeremy J. McCormick, Sandra E. Klein Foot & Ankle International August 28, 2015
Maybe somewhere else but the USA.
However, in the USA, if you didn't do a micro examination of the excised tissue, and the patient ended up have a bad surgical result and sued the surgeon for not taking out a neuroma but rather claims that other vital tissue was removed that caused them pain, suffering, psychological harm and ruined their sex life, the surgeon would forever be regretting not doing that micro examination on that removed tissue.
This is why the current USA medical system is so expensive..we must continually cover ourselves by performing expensive tests to protect ourselves from frivolous lawsuits from our patients.
Is the thumb forefinger squeeze test routinely taught in British schools?
The test I was taught consisted of lateral compression of the forefoot in an attempt to squeeze any neuroma between the metatarsal heads.
It seemed to me that the test assumed that the affected portion of the digital nerve was permanently trapped between the metatarsal heads which was not how I understood things. Mulder's click I thought resulted from the neuroma being pushed from an abnormal position, between the metatarsal heads, plantarly into its 'normal' position. Therefore in a patient with a Morton's neuroma the neuroma could be either in it's normal position, ie not trapped between the metatarsal heads and not causing pain or in an abnormal position, ie compressed between the metatarsal heads.
I wonder if the accuracy and sensitivity of the thumb digital sqeeze test could be improved (not that there's much room for improvement) if the lateral sqeeze test and a the dorsoplantar thumb forefinger squeeze test were combined in a timely manner?
My sequencing would be as follows:
With the patient non-weightbearing, at the affected intermetatarsal space push upwards with the thumb in an attempt to push any neuroma out of its normal position and into an abnormal position between the metatarsal heads.
Maintain the dorsal pressure with the thumb and then begin to squeeze the metatarsal heads together laterally to ensure that there is sufficient pressure on any neuroma to elicit symptoms. If this elicits pain it would be considered as evidence of the presence of Morton's neuroma.
Now use the forefinger to press plantarly and slowly release the lateral pressure. The plantar pressure is applied in an atempt to push a displaced digital nerve back into its normal position. Evidence of success is the production of Mulder's click and a rapid reduction in symptoms.
If no symptoms are produced on the first occasion repeat the procedure.
Oh, and by the way, neuromas in the third intermetatarsal space should be more rightly called "Durlacher's Neuroma" rather than "Morton's Neuroma" since Lewis Durlacher first described the intermetatarsal neuroma, 35 years before T.G. Morton described it (Durlacher L:
A Concise Treatise on Corns, Bunions, and the Disorders of Nails with Advice for the General Management of the Feet. Simpkin, Marshall and Co, London, 1845, pp. 30).
I enjoyed Ted & David's enthusiastic endorsement of manipulative therapy for Morton's Neuroma. The audio interview with David, A Scottish Podiatrist who specializes
in Muscolo-skeletal therapy, provides little useful insight to know what technique is used.
The manipulation treatment, David advises, can be somewhat painful, but
a patient may be rewarded with instant (but transient) pain relief. Several, or many, treatments may be required to make a patient progressively asymptomatic for longer intervals between adjustment, and further adjustments may be required. The longevity of the beneficial effect is as yet unknown.
David is enthusiastic also about two studies that demonstrate that a clinical diagnosis is as good, or better than imaging studies (US/MRI) - the authors suggest that imaging studies are therefore mostly unnecessary, unless there is doubt about the diagnosis or there is clinical suspicion of multiple webspace involvement.
This can be of significance in the UK where a patient may wait quite some time for access to NHS imaging services. In the US imaging can be performed swiftly and with minimal delay and positive studies can provide a further layer of medico-legal defense and assist with the insurance claim. A false negative finding from the MRI / US, on the other hand, is possible and equally unhelpful.
I might add that imaging studies can be helpful also to rule out other pathologies. This might be useful before attempting a high velocity, low amplitude manipulative maneuver. Both Ted & David report no adverse effects.
A RCT trial is under way and may help answer some of the questions. I look forward to the results of this work.
The clinical diagnosis of symptomatic forefoot neuroma in the general population: a Delphi consensus study
Charlotte Dando, Lindsey Cherry, Lyndon Jones and Catherine Bowen Journal of Foot and Ankle Research201710:59
Relationship Between Sensory Symptoms, Mulder's Sign, and Dynamic Ultrasonographic Findings in Morton's Neuroma
Luca Padua et al Foot Ankle Int. 2020 Aug 28