Simple Neurectomy Versus Neurectomy With Intramuscular Implantation for Interdigital Neuroma: A Comparative Study.

BACKGROUND: Simple neurectomy is a standard treatment of interdigital nerve neuroma after failure of conservative treatment. Recently, neurectomy with intramuscular implantation of the proximal nerve stump has been proposed as a safe and effective alternative method providing significant pain improvement. However, there remains little evidence supporting one technique over the other. The purpose of this study was to compare functional outcomes and complications of simple neurectomy versus neurectomy with intramuscular implantation.

METHODS: Retrospective chart review along with prospectively collected data of 99 consecutive patients (105 feet with 118 neuromas) who were diagnosed with interdigital neuroma of the foot and underwent simple neurectomy (66 patients / 72 feet / 78 neuromas) and neurectomy with intramuscular implantation of proximal nerve stump into intrinsic muscle of foot (33 patients / 33 feet / 40 neuromas) between 2000 and 2013. The minimum follow-up to be included in the study was 6 months for both techniques (mean = 44.6 months, range = 6 to 150 months for simple neurectomy; and mean = 19.3 months, range = 6 to 66 months for neurectomy with intramuscular implantation of proximal nerve stump into the intrinsic muscle). The primary outcomes were Foot Function Index (FFI); pain, disability, activity limitation, and total score, Short Form-36 (SF-36: physical and mental component scores); and visual analog scale (VAS). Secondary outcomes included operative time and complications. Pre- and postoperative SF-36, and FFI, and pain (VAS) scores were obtained and compared using a paired t test. An independent t test was used to assess the functional outcomes and operative time between the 2 groups, and a chi-square test was used to compare the complications between the 2 techniques.

RESULTS: Both groups demonstrated significant improvement of postoperative functional outcomes (FFI, SF-36, and VAS; P < .001, all) compared to the preoperative period. Neurectomy with intramuscular implantation demonstrated significant improvement of pain compared to simple neurectomy as measured with VAS (P = .002); however, the operative time was significantly longer than the simple neurectomy technique (P = .001). The rest of the functional outcomes measured were comparable between the 2 techniques. Complications in both simple neurectomy and implantation techniques were persistent pain (11.5% vs. 2.5%, P = .07), revision rate (5.1% vs. 0.0%, P = .08), and painful scar (5.1% vs. 5.0%, P = .83), respectively, but it did not reach statistical significance (P > .05, all).

CONCLUSION: Both simple neurectomy and neurectomy with intramuscular implantation demonstrated significant improvement in terms of functional outcomes as measured with the FFI, SF-36, and VAS in patients with interdigital neuroma. Although requiring a longer operative time, neurectomy with intramuscular implantation technique might offer superior pain relief with comparable complications to the simple neurectomy technique.