Rehabilitation Program
Physical Therapy
Treatment strategies for Morton's neuroma range from conservative to surgical management. The conservative approach to treating Morton's neuroma may benefit from the involvement of a physical therapist. The physical therapist can assist the physician in decisions regarding the modification of footwear, which is the first treatment step. Recommend soft-soled shoes with a wide toe box and low heel (eg, an athletic shoe). High-heeled, narrow, nonpadded shoes should not be worn, because they aggravate the condition.
The next step in conservative management is to alter alignment of the metatarsal heads. One recommended action is to elevate the metatarsal head medial and adjacent to the neuroma, thereby preventing compression and irritation of the digital nerve. A plantar pad is used most often for elevation. Have the patient insert a felt or gel pad into the shoe to achieve the desired elevation of the above metatarsal head.
Other possible physical therapy treatment ideas for patients with Morton's neuroma include cryotherapy, ultrasound, deep tissue massage, and stretching exercises. Ice is beneficial to decrease the associated inflammation. Phonophoresis also can be used, rather than just ultrasound, to further decrease pain and inflammation.
Surgical Intervention
When conservative measures for Morton's neuroma are unsuccessful, surgical excision of the area of fibrosis in the common digital nerve (as demonstrated in the images below) may be curative. Common adverse outcomes include dysesthesias radiating from a painful nerve stump after surgical excision of the Morton's neuroma. Dysesthesias may be treated as any other dysesthetic pain. (See Medication.) [15, 16, 17, 18, 19, 20]
Surgical options include the following:
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Transverse intermetatarsal ligament release, with or without neurolysis
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Endoscopic decompression of the transverse metatarsal ligament
A dorsal surgical approach may decrease recovery time, [24] although a study by Kundert et al indicated that a longitudinal plantar approach to excision of Morton neuroma is also effective, providing strong pain relief; [25] a study by Habashy et al found comparable outcomes and patient satisfaction with either a plantar (17 patients) or dorsal (20 patients) approach to neurectomy for Morton neuroma. [26, 27]
A study by Reichert et al of the long-term outcomes of dorsal neurectomy indicated that this remains a useful treatment for Morton neuroma, despite the existence of other, less-invasive therapeutic techniques. The study, which involved 41 patients and had an average follow-up time of 7.4 years, found that the mean American Orthopaedic Foot and Ankle Society (AOFAS) score rose from 39.4 (preoperatively) to 83.4 (postoperatively), while the mean visual analog scale score fell from 7.04 (preoperatively) to 1.4 (postoperatively). The report also determined that the best results were obtained in patients with single neuromas over 3 mm in size and resected within 12 months of symptom onset. [28]
A retrospective study by Lee et al suggested that treatment of Morton’s neuroma with a sliding osteotomy on the proximal metatarsal bone can be a relatively effective means of pain relief. The investigators reported improvements in the AOFAS Lesser Metatarsophalangeal-Interphalangeal Scale and Foot Function Index scores, from 52.1 and 62.4, respectively, preoperatively, to 74.2 and 31.3, respectively, postoperatively. [29]
Consultations
If surgical intervention is needed for Morton's neuroma, consultation with an orthopedic surgeon specializing in foot and ankle surgery is recommended.
Other Treatment
Corticosteroid injections
Another treatment approach involves injection of the Morton's neuroma. [9, 10] Perform injection into the dorsal aspect of the foot, 1-2 cm proximal to the webspace, in line with the MTP joints. Advance the needle through the mid-webspace into the plantar aspect of the foot until the needle gently tents the skin. Then withdraw it about 1 cm to where the tip of the neuroma is located. Inject a corticosteroid/anesthetic mix. A reasonable volume is 1 mL of corticosteroid and 2 mL of anesthetic. The anesthetic used should not contain epinephrine, as necrosis may result. Care also should be taken not to inject into the plantar pad. [30]
Studies indicate that a dorsal approach may decrease patient discomfort. [31]
Adverse outcomes from corticosteroid injection include plantar fat pad necrosis. Transient numbness of the toes also may occur. Although many practitioners use multiple injections, the likelihood of benefit from subsequent injections, after failure to achieve relief from the initial injection, is negligible.
An Australian investigation using a single, ultrasonographically guided corticosteroid injection for Morton's neuroma found that 9 months after treatment, complete pain relief had occurred in 11 of the 39 neuromas studied. [32]
A literature review by Edwards et al indicated that in adults with Morton’s neuroma, short- to medium-term pain benefits can be derived from a single corticosteroid injection, with the rate of ensuing adverse events being low; [33] a study by Hau et al found that at a mean 4.8-year follow-up, a single corticosteroid injection remained effective in 38% of Morton’s neuromas. [34] However, Edwards and colleagues found that while the injection was apparently superior to usual care, it was not clear whether it was superior to local anesthetic alone, and it showed inferiority to surgical excision. [33]
A study by Lizano-Díez et al found no additional pain-relief benefit to injections combining a corticosteroid with a local anesthetic compared with those using a local anesthetic alone, in patients with Morton’s neuroma. Patients in the study received three injections, with the investigators determining at 3- and 6-month follow-up that patients who received the corticosteroid/anesthetic combination did not significantly differ from the anesthetic-only patients with regard to improvement in pain and function. [35]
A study by Park et al indicated that in patients who receive corticosteroid injection for treatment of Morton’s neuroma, the sole ultrasonographic predictor of treatment failure is the size of the neuroma, with the parameters of intermetatarsal distance and the proportion of neuroma in the intermetatarsal space being prognostically insignificant. The investigators found that failure occurred in patients with a mean neuroma size of 7.9 mm, while treatment was successful in the group with a mean neuroma size of 5.5 mm. [36]
Extracorporeal shockwave therapy
Fridman et al investigated the efficacy of extracorporeal shockwave therapy in the treatment of Morton's neuroma. The study included 23 patients who, after more than 8 months of conservative therapy, had a visual analog scale (VAS) pain score of at least 4. In the study, 13 patients were treated with shockwave therapy, with the rest receiving a sham treatment. By 12-week posttreatment follow-up, members of the shockwave treatment group showed a significant reduction in their VAS pain score, whereas patients in the sham treatment group did not. The authors concluded that extracorporeal shockwave therapy may be an effective alternative to surgical excision in the treatment of Morton's neuroma. [37]
Radiofrequency ablation
A further nonsurgical option includes thermoneurolysis with percutaneous radiofrequency ablation. This method heats the nerve with radiofrequency to the point of neurolysis and may be as effective as surgical intervention. [38]
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Plantar view showing the relationships between the metatarsal heads, the intermetatarsal ligament, and the neuroma.
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Neurectomy: typical incision location.
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Neurectomy: superficial exposure.
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Neurectomy: deeper dissection.
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Neuroma and adherent fibrofatty tissue.
