Efficacy of Ultrasound-Guided Steroid Injections in the Management of Morton's Neuroma: A Retrospective Cohort Study.

backgroundMorton's neuroma, a common painful neuropathy of the forefoot, is characterised by fibrotic thickening of plantar digital nerves. Patients often present with forefoot symptoms such as pain, burning, tingling or numbness, typically at the third web space. The exact cause of Morton's neuroma is not fully understood. The most accepted theory suggests that Morton's neuroma is caused by chronic repetitive microtrauma. Ultrasound (US)-guided corticosteroid injections can be used for symptom relief, but their pain-relieving efficacy is still unclear.

methodsThis retrospective cohort study evaluated the efficacy of US-guided corticosteroid injections in treating pain associated with Morton's neuroma, and whether the neuroma size influences pain severity or response following corticosteroid injection. The data captured via SECTRA IDS7 (Sectra AB, Linköping, Sweden) were organised into the following categories: age, sex, smoking status, neuroma size and pre-injection and post-injection pain scores. Variables were analysed through statistical tests including analysis of variance (ANOVA), Spearman's rank correlation coefficient and the Wilcoxon signed-rank test coefficient.

resultsData from 20 eligible patients demonstrated that US-guided corticosteroid injections are 85% effective in controlling pain associated with Morton's neuroma. The median duration of pain relief was 17 months, and the interquartile range (IQR) was 18 months (Q1=6, Q3=24). The mean visual analogue scale (VAS) scores decreased from 7.7 before injection to 2.2 after injection (P=0.006). The size of the neuroma at the time of the US scan was not related to pain severity or outcomes in terms of reduction in pain score (P=0.767). Female sex was associated with a greater reduction in the VAS pain score; however, this difference was not statistically significant (P=0.33). A P-value of less than 0.05 was used to determine significance. Six (30%) of the patients needed downstream surgery, which indicated the degree of recurrence or severity of pain.

conclusionsUS-guided corticosteroid injections are safe, effective and reasonable treatment choices for Morton's neuroma, with variable durations of relief. No complications were observed in our study group following the intervention. Further research using a larger patient cohort is needed. This is to determine whether there are any associations between the efficacy of pain reduction in female patients and that in male patients. It will also assess whether neuroma size may be related to corticosteroid treatment response and highlight those who may benefit from earlier surgery.