CA S E R E PORTMcG i l l Jou rna l o f Med i c i n e

Depression and Anxiety as Important AggravatingFactors of Pain in Morton’s Neuroma: A CaseReport

Golale Modarresi1 | Shirin Modarresi2

1Bridgepoint Collaboratory for Researchand Innovation, Lunenfeld-TanenbaumResearch Institute, Sinai Health, Toronto,Ontario, Canada2School of Physical Therapy, WesternUniversity, London, Ontario, CanadaCorrespondenceShirin ModarresiEmail: smodarre@uwo.caPublication DateSeptember 10, 2021MJM 2022 (20) 7https://doi.org/10.26443/mjm.v20i1.884

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This work is licensed under a CreativeCommons BY-NC-SA 4.0 InternationalLicense.

AB S T R AC TThis report represents a case of Morton’s neuroma with episodic se-

vere pain in the forefoot. Initially, the patient was prescribed naproxen500mg twice per day, anti-inflammatory topical cream, andmassage. In afollow up visit, the patient was still experiencing frequent episodic sharppain. In a detailed patient interview, it was revealed that she has depres-sion and anxiety and suffers from social isolation, which co-occurredwithepisodes of severe pain. Therefore, she was referred to a psychologistand a community support group and started practicing body relaxationtechniques such as guided imagery and breathing exercises. The newtreatment strategy had a major impact on improving her symptoms. Thisreport aims to illustrate that depression and anxiety can be one of themain aggravating factors in conditions that cause episodic pain, as in thiscase of Morton’s neuroma. Removing psychosocial contributors of painhas the potential to decrease the need for more invasive interventions.

L E A RN I NG PO I N T S• This study highlights the importance of recognizing psychosocial con-

tributors of pain in a case of Morton’s neuroma• Taking a detailed history is essential to recognize all the potential trig-

gers of pain, even when the disorder has a typical presentation withan identified pathology

• By evaluating and identifying psychosocial contributors, the necessityof painkillers and invasive interventions can subsideK E YWORD S

Morton’s neuroma, Pain, Biopsychosocial model

1

2 Modarresi1 | INTRODUCTION

Morton’s neuroma is one of the most common causesof forefoot pain. (1) It can develop when the tissuesand bursa surrounding an interdigital nerve thicken fromchronic pressure and lead to swelling or fibrosis aroundthe vessels and the nerve. (2) The resultant neuropathyis mainly due to irritation of the interdigital nerves closeto the plantar aspect of the transverse intermetatarsalligament during dorsiflexion. (2) Common causes in-clude narrow toe-box footwear, high heels, lipoma, jointdislocations, repetitive trauma, or blunt injury. (3)

Morton’s neuroma mostly occurs between the thirdand fourth metatarsals and pain may radiate to othertoes, though occurrences between the second and thirdmetatarsals has also been reported. (4) The most com-mon aggravating factor is walking, especially in tight orhigh-heeled shoes, and the most common relieving fac-tors are resting and taking off footwear. (2) Numbnessand night-time awakening pain can happen, (4) and withprolonged activity, pain can radiate to the calf and otherparts of the foot as well. (2) The first-line treatment op-tion is supportive care, such aswearing awide shoewithsoft insoles and a low heel that unloads the pressureon the nerve. (2) Nonsteroidal anti-inflammatory drugs,anti-epileptic medications, and tricyclic antidepressantsmay also be effective. (2) Injection of anesthetics asa gentle invasive treatment is used as second line. (2)Steroid injection is a short-term effective symptom re-liever but may cause side effects, including atrophy ofthe subcutaneous fat, skin thinning, and even deformity.(2) The effectiveness of surgical interventions remainscontroversial thus, they are usually reserved for whenconservative management has failed for at least severalmonths. (3) The CARE guideline was used to guide thiscase report. (5)

2 | CASE REPORT

Patient’s presenting profile: the patient is a 70-year-oldfemale, admitted to the outpatient department, com-plaining of sharp and severe episodic pain in the tip

of the left second distal phalanx. Subjective historyrevealed an insidious onset that started around sevenyears ago with no known history of trauma. Since then,the patient has been changing her footwear regularly,as it alleviates her pain. While she has excruciatingpain, she notices warmth and visible bulging of the veinson her foot however, denies any numbness, tingling, orcramps. Over the course of two years, her pain hasintensified and the periodic events no longer correlatewith activity, which was previously an aggravating fac-tor for pain. Nevertheless, she does mention that longwalks bring forth a tingling sensation in the forefoot. Inorder to alleviate her pain, she has been taking over-the-counter medications, including ibuprofen and topicalremedies. Unfortunately, these medications have pro-vided no relief. Furthermore, the patient denies wear-ing tight shoes, and reports performing a mild level ofphysical activity (i.e., slow-paced walking). The persis-tent pain has been distressing her, as she expresses feel-ings of nervousness and hopelessness.

Past medical history: her past medical history con-sists of hallux valgus correction surgery done on bilat-eral feet four years ago, with no post-operation com-plications. She denies wearing high heels for over 45years. She also reports taking 20 mg of citalopram dailyfor mild depression for the past fifteen years. The pa-tient denies diabetes, rheumatic diseases, allergies, kid-ney, liver dysfunction, recreational drugs, alcohol abuse,and any family history of similar type of pain.

Physical examination: vital signs and bodymass indexwere normal. On inspection, there were no swelling, dis-coloration, or atrophy at the location of the pain. Theshape and color of the nails were normal. There wasno warmth, mass, crunching, lump, or clicking. On pal-pation, save for the second toe, other parts of the leftfoot had no tenderness. Dorsalis Pedis and Tibialis ar-teries’ pulses, as well as capillary fillings were normal.The dermatomal assessment was symmetrical and unre-markable. The range of motion of the joints were withinnormal limits. On X-ray, no signs of fracture, injury, ortrauma to the second metatarsal and phalanx were vis-ible. On MRI, Morton’s neuroma by the second meta-tarsal was detected by a radiologist (Figure 1). The pa-

Modarresi 3

F IGURE 1 MRI scan of the left foot showingMorton’s neuroma at the second metatarsal.

tient rated her pain at 8/10 on the numeric pain ratingscale (NPRS). A squeeze test was performed by applyingpressure on the dorsal and plantar surface of the sec-ond distal meta-tarsal. A Morton’s test was conductedin which one hand was placed on the medial side of thepatient’s foot near the metatarsophalangeal joint, andthe other hand was placed on the lateral side, and pres-sure was applied to squeeze the two sides. The resultsof both tests were positive with the reproduction of thefamiliar pain. The patient was advised to use topicalsalicylate ointment and to gently massage the secondand third metatarsals by spreading and mobilizing themetatarsal heads. She was also advised to take 500 mgnaproxen, a maximum of two tablets daily.

Psychosocial assessment: Three weeks later, the pa-tient still reported the same amount of pain in a follow-up visit. During this visit, a more thorough patient inter-view including evaluations of social and psychologicalfactors was conducted. The patient revealed that shesuffers from social isolation with no family and socialsupport. In addition, the patient indicated that she hasbeen experiencing anxiety in the past two years, whichwas concurrent with the severe pain onset. She dis-

played depression and anxiety symptoms, including ner-vousness, restlessness, agitation, fatigue, sadness, andloss of interest in activities of daily living (ADLs). Ac-cording to the patient, her mental health also affects herappetite, ADLs, and sleep quality. Her score on the Hos-pital Anxiety andDepression Scalewas 15/21, depictingpresence of depression and anxiety.

Analysis: Upon further investigation, it was revealedthat her pain exacerbates at times of severe depressionand anxiety. In other words, there was a strong correla-tion between episodes of pain in the forefoot and whenshe felt extremely sad and anxious. Based on this find-ing, she was referred to a psychologist for weekly ses-sions and a community support group to address hersocial isolation. In the meantime, she started body re-laxation techniques such as guided imagery and breath-ing exercises on a daily basis (at least one or two timesper day). These strategies were in addition to the pre-viously prescribed treatments such as specific massagetechniques, naproxen, and topical salicylate ointment.After four weeks, in a follow-up visit, her pain level haddecreased to 4/10 on the NPRS, which was controllableby taking 500 mg naproxen a day. The patient’s mentalstatus improved, and she reported a significant decreasein the frequency of painful forefoot episodes.

3 | DISCUSSION

To the authors’ knowledge, this is the first case reportof a patient with Morton’s neuroma having social andpsychological factors as the main triggers of pain. Thisstudy highlights the necessity for considering these trig-gers and working towards removing them to not only re-duce the need for pharmacological treatments, but alsodecrease the necessity of invasive interventions. Thisfinding is in line with the biopsychosocial model of pain,which posits that not only tissue pathology contributesto the experience of pain, but that also social and psy-chological factors play important roles. (6)

Psychological factors such as depression have beenreported as significant predictors of chronic pain fol-lowing an injury. (7) Uncovering the exact underlying

4 Modarresimechanism of how psychosocial factors could have af-fected the experience of pain for this patient is beyondthe scope of this paper however, we can offer some ex-planations. Previous research has shown that peoplewith high levels of anxiety are more sensitive to pain,and stress or other negative emotions are associatedwith lower pain thresholds. (8) In addition, pain sharessome common biological mechanisms with depressionand anxiety. For instance, various parts of the brain havevital roles in processing both anxiety and pain such asthe periaqueductal gray and anterior cingulate cortex,as both regions get activated while feeling either painor anxiety. (9) Even the severity of pain and psychologi-cal disorders are significantly correlated with each other.(10) This overlap of biological mechanisms can also leadto a vicious cycle between pain and psychological disor-ders, as pain is a risk factor for developing depressionand anxiety. (9) Also, neurotransmitters such as gluta-mate have shown to play essential roles in regulatingboth mental health and pain. (9) In addition, emotionaldisorders might affect pain through other health behav-iors such as nutrition and sleep. (7) Therefore, cliniciansare recommended to screen for depression and anxiety,especially if the patient suffers from severe chronic pain.Focusing on typical causes and triggers may hinder theclinicians’ and the patients’ awareness that an underly-ing psychiatric condition may exist and potentially playa significant role. By going beyond the pathophysiol-ogy of a disorder, identifying the psychosocial contrib-utors of pain, and implementing these factors into themanagement strategy, we can decrease the necessity ofpainkillers and invasive interventions, and optimize indi-vidualized care that is evidence-based and comprehen-sive.

This case report’s principal strength is that it providesa clear example of how psychosocial factors can be themain triggers of pain, in this case for a patient with Mor-ton’s neuroma. The main limitation is the inability to cre-ate a causal link between depression/anxiety and theepisodic periods of pain. Further research is requiredto establish a definite cause and effect relationship. In-formed consent was obtained from the patient for thiscase report.

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