Evaluation of MRI features of neuromas in oncological amputees, and the relation to pain.

The impact of time on neuroma growth and morphology on pain intensity is unknown. This study aims to assess magnetic resonance imaging (MRI) differences between symptomatic and non-symptomatic neuromas in oncological amputees, and whether time influences MRI-detected neuroma dimensions and their association with pain. Oncological patients who underwent traditional extremity amputation were included. Post-amputation MRIs were assessed before decision for neuroma surgery. Chart review was performed for residual limb pain (numeric rating scale, 0-10) and the presence of neuropathic symptoms. Neuromas were classified as symptomatic or non-symptomatic, with neuroma size expressed as radiological neuroma-to-nerve-ratio (NNR). Among 78 neuromas in 60 patients, the median NNR was 2.0, and 56 neuromas (71.8%) were symptomatic with a median pain score of 3.5. NNR showed no association with symptomatology or pain intensity but correlated with a longer time-to-neuroma-excision interval and a smaller nerve caliber. Symptomatic neuromas were associated with lower extremity amputation, T2 heterogeneity, and the presence of heterotopic ossification. Lower extremity amputation, T2 heterogeneity, perineural edema, and presence of heterotopic ossification were associated with more painful neuromas. MRI features associated with symptomatic neuromas and pain intensity were identified. Awareness of the potential clinical significance of these imaging features may help in the interpretation of MRI exams and may aid clinicians in patient selection for neuroma surgery in oncological amputees.

van Vliet E ，Raasveld FV ，Liu WC ，Valerio IL ，Eberlin KR ，Newman ET ，Jarraya M ，Simeone FJ ，Husseini JS ... -  《-》

MRI features of symptomatic amputation neuromas.

To demonstrate the magnetic resonance imaging (MRI) features of amputation neuromas in lower extremity amputees and investigate independent predictive MRI features for symptomatic neuromas. This retrospective study included 45 amputation neuromas in 44 lower extremity amputees. Two radiologists assessed the imaging features, including shape, size, type (end-bulb or spindle), signal intensity (SI), heterogeneity, margins, enlarged fascicles, dark outer rim, tail sign, target sign, enhancement, perilesional fibrosis, and muscle denervation. The neuromas were categorized into symptomatic (n = 24) or asymptomatic (n = 21). Symptomatic neuromas were determined based on neuropathic pain characteristics, the presence of Tinel's sign or tenderness, and response to local anesthetic injection. Univariate and multivariate analyses were performed to identify independent predictive MRI features. Of 45 neuromas, 80% (36/45) were end-bulb neuromas and 20% (9/45) were spindle-type neuromas. Eighty percent of the neuromas (36/45) were heterogeneous on T2-weighted images (WIs). Enlarged fascicles were present in 42% (19/45) and dark outer rims in 27% (12/45) of the neuromas. Among the 23 neuromas with enhanced images, 78% (18/23) showed enhancement. Heterogeneity on T2-WIs and enhancement ratios were significantly different between the asymptomatic and symptomatic neuroma groups (p < 0.05). The multivariate analyses indicated that heterogeneity on T2-WIs was an independent factor associated with symptomatic neuromas (p < 0.001). Heterogeneity on T2-WIs could be a predictive indicator for symptomatic neuromas in lower extremity amputees. • Amputation neuromas are classified as either end-bulb or spindle-type. They can show enlarged fascicles, dark outer rims, and enhancement. • Heterogeneity on T2-weighted images could be a predictive indicator for symptomatic neuromas. • Predicting the symptomatic neuroma on MRI would help in effective management of stump pain.

Chung BM ，Lee GY ，Kim WT ，Kim I ，Lee Y ，Park SB ... -  《-》

Heterotopic Ossification Is Associated with Painful Neuromas in Transtibial Amputees Undergoing Surgical Treatment of Symptomatic Neuromas.

A relationship between nerve and osseous regeneration has been described. During the surgical treatment of symptomatic neuroma in transtibial amputees, the authors have found that heterotopic ossification (HO) depicted on preoperative radiographs appeared to be associated with the location of symptomatic neuromas in both the peroneal and tibial nerve distributions. Data were collected for transtibial amputees who underwent surgical management of symptomatic neuroma and were prospectively enrolled from 2018 through 2023. Preoperative radiographs were assessed for the presence of HO located at the distal fibula and tibia. The presence of a peroneal or tibial neuroma was based on findings contained within the operative reports. Pain levels were measured on a numeric rating scale (0 to 10). Sixty-five limbs of 62 amputees were included. Peroneal neuroma and presence of fibular HO ( P = 0.001) and tibial neuroma and presence of tibial HO ( P = 0.038) demonstrated an association. The odds of having a symptomatic peroneal neuroma with fibular HO present were greater than the odds of a symptomatic peroneal neuroma when fibular HO was absent (OR, 9.3 [95% CI, 1.9 to -45.6]; P = 0.006). Preoperative pain scores were significantly higher for all patients with HO ( P < 0.001), those with fibular HO ( P < 0.001), and those with tibial HO ( P < 0.001), compared with patients without HO. In patients with symptomatic neuromas, preoperative pain was worse when HO was present in the transtibial amputee's residual limb. Further research on the neuroma-HO complex in symptomatic amputees is required. Risk, III.

Raasveld FV ，Liu WC ，Renthal WR ，Fleming ME ，Valerio IL ，Eberlin KR ... -  《-》

Neuroma-to-Nerve Ratio: Does Size Matter?

Anatomic features of neuromas have been explored in imaging studies. However, there has been limited research into these features using resected, ex vivo human neuroma specimens. The aim of this study was to investigate the influence that time may have on neuroma growth and size, and the clinical significance of these parameters. Patients who underwent neuroma excision between 2022 through 2023 were prospectively included in this study. Neuroma specimens were obtained after operative resection. Standardized neuroma size measurements, expressed as a neuroma-to-nerve ratio (NNR), were conducted with ImageJ software. Pain data (numeric rating scale, 0-10) were prospectively recorded during preoperative evaluation, and patient factors were collected from chart reviews. Fifty terminal neuroma specimens from 31 patients were included, with 94.0% of the neuromas obtained from individuals with amputations. Most neuromas were excised from the lower extremities (n = 44, 88.0%). The neuromas had a median NNR of 2.45, and the median injury to neuroma excision interval was 6.3 years. Larger NNRs were associated with a longer injury to neuroma excision interval and with a smaller native nerve diameter. In addition, sensory nerves were associated with a larger NNR compared with mixed nerves. NNR was not associated with preoperative pain or with anatomical nerve distribution. This study suggests that neuromas seem to continue to grow over time and that smaller nerves may form relatively larger neuromas. In addition, sensory nerves develop relatively larger neuromas compared with mixed nerves. Neuroma size does not appear to correlate with pain severity. These findings may stimulate future research efforts and contribute to a better understanding of symptomatic neuroma development.

Weigel DT ，Raasveld FV ，Liu WC ，Mayrhofer-Schmid M ，Hwang CD ，Tereshenko V ，Renthal W ，Woolf CJ ，Valerio IL ，Eberlin KR ... -  《-》

Neuromas as the cause of pain in the residual limbs of amputees. An ultrasound study.

To explore the morphology of neuromas and to determine the differences, if any, between asymptomatic and symptomatic neuromas using ultrasound. Eighty patients with symptomatic neuromas were included in this retrospective review. High-resolution ultrasound examination was performed. Transducer pressure allowed real-time analysis of both symptomatic and asymptomatic neuromas. Quantifiable assessment of pain by the patient assigned a pain score of 0, 1, 2, or 3, to each neuroma. One hundred and fifty-nine neuromas were identified in total. Fifty-three neuromas were asymptomatic (pain score=0), very severe pain was recorded in 54 (pain score=3), 16 neuromas were mildly painful (pain score=1) and 36 were moderately painful (pain score=2). The average number of neuromas per patient was 1.98, and the average number of symptomatic neuromas per patient was 1.3. There was no correlation between pain score and patient age, neuroma volume, amputation type, and time since amputation. High-resolution ultrasound can distinguish between asymptomatic and symptomatic neuromas. Patient age, time since amputation, the type of amputation, and the neuroma volume were not related to the presence of pain.

O'Reilly MAR ，O'Reilly PMR ，Sheahan JN ，Sullivan J ，O'Reilly HM ，O'Reilly MJ ... -  《-》