Review Question - QID 219528

This 44-year-old female has a presentation highly concerning for an interdigital (Morton's) neuroma of the right foot. The most appropriate first step in management is to use a metatarsal pad to offload the metatarsal heads.

Interdigital neuromas of the feet are characterized as compressive neuropathies of the digital nerves, with a strong predilection for middle-aged females. While the pathophysiology behind interdigital neuromas isn't fully understood, many theorize that repeated trauma to the transverse intermetatarsal ligament contributes to the development of symptoms. As such, nonoperative management in the form of metatarsal pads is often employed to offload the metatarsal heads by increasing the intermetatarsal space, thereby reducing the pressure on the interdigital nerves. When patients fail nonoperative efforts, surgery is often undertaken, which includes neuroma resection.

Bennett et al. performed a retrospective review of 115 patients with interdigital neuromas who underwent a staged treatment program, which began with shoewear modifications before progressing to steroid injections and ultimately, a neurectomy if required. Approximately 85% sustained relief with the program, with 21% requiring neurectomy and 96% of those requiring neurectomy reporting satisfactory results. The authors conclude the presented treatment algorithm provides satisfactory treatment for patients with interdigital neuromas.

Bhatia and Thomson reviewed the pathophysiology, symptomatology, diagnostics, and management of Morton's neuromas. The authors report the condition is often related to nerve fibrosis following repeated trauma, which ultimately creates a neuroma and causes pain and dysesthesias in the affected nerve's distribution. The authors conclude by discussing the nonsurgical options (orthotics, steroid injections) before examining the surgical options, which includes neurectomy through the dorsal approach to avoid wound-related complications.

Figure A represents a Morton extension orthosis. Figure B is a longitudinal arch support. Figure C is a carbon fiber shoe insert. Figure D is a metatarsal pad. Figure E is ankle foot orthosis.

Incorrect answers:
Answer 1: Morton extension orthoses are used for hallux rigidus to avoid excessive great toe metatarsophalangeal joint extension.
Answer 2: Longitudinal arch supports are often employed for those with posterior tibial tendonitis.
Answer 3: Carbon fiber inserts are often employed for those with midfoot arthritis.
Answer 5: Ankle-foot orthoses are commonly used for patients with peroneal nerve palsies and its associated foot drop.