Maria Buitrago, DPM, MS, FACFAS, FAENS TPMA/Dallas County Winter Meeting January 25-26, 2014          Neuroma: general concepts Diagnosis Treatment algorithm Radiofrequency ablation Continuous Radiofrequency ablation Pulsed Radiofrequency ablation Literature Review Case Study Summary Neuroma – a benign enlargement of the digital branch of the medial or lateral plantar nerve, most frequently third interspace.  Morton’s entrapment or Morton’s neuroma   Compression neuropathy of the plantar digital nerve against the transverse intermetatarsal ligament.      Clinical Presentation Ultrasound X-ray MRI Diagnostic Injections Neuroma ↓ Non-Operative interventions ↓ Surgical Decompression (open or endoscopic) ↓ Radiofrequency Ablation (RF) ↓ Open Neurectomy→stump neuroma→RF  Open Neurectomy o Generally accepted o Failure rates 14-21%, studies Bennett & Graham, Foot Ankle Int. 1995 and Diebold & Daum, Orthopedics, 1996. o More recently, Womack & Richardson, Foot Ankle Int, 2008, reported out of 120 patients only 50% had a good to excellent result, 10% fair and 40% poor outcome. o Lee & Kim, Foot Ankle Specialists, 2011, reported only 61% good outcomes from neurectomy long term.  The destruction of a specific biological tissue utilizing electricity generated from a radio-frequency wave.  The electrical current causes ionic agitation of soft tissue molecules which results in frictional heating. Radiofrequency Machine and Probe  Continuous Radiofrequency Ablation (CRF)  Pulsed Radiofrequency Ablation (PRF)  Higher temperatures over 70 degrees Celsius  Continuous RF results in the selective destruction of paincarrying nerve fibers (A-delta and C fibers, not the A-beta fibers).  Instant tissue coagulation and cell death resulting in destruction of neural tissue.  Apply intermittently at lower temperatures, 40 degrees Celsius  Use higher voltage that produces a brief rise in temperature followed by elimination of heat at timed intervals.  Mechanism of Action is unclear  The mean tip temperature remains below the neurodestructive range, which preserves the structural integrity of the nerve.  Prevents the nerve from transmitting pain while preserving sensory function. Cahana A, Vutskits L, Muller D. Acute differential modulation of synaptic transmission and cell survival exposure to pulsed and continuous radiofrequency energy. J Pain 2003 4:197-202.  Finney, et al. Treatment of Morton’s Neuroma Using Percutaneous Electrocoagulation. JAPMA.1989. Vol 79:12. 615-618  Retrospective analysis 79 nerve lesions in 71 patients treated with RFA 12 stump neuroma and 69 failed conservative treatment. Pain rating 0-5, pre op 4.56 and post op 2.02 71% patients reported symptoms improved or completely gone.      Tamimi et al. A Case Series of Pulsed Radiofrequency Treatment of Myofascial Trigger Points and Scar Neuromas. Pain Medicine. 2009.  Retrospective analysis 9 patients treated over 18 months failed conservative treatment. 8/9, 75-100% reduction in pain-4weeks, 67% pain relief 6 mths, only 1 patient experienced no pain relief.    Genon et al. Radiofrequency ablation for the treatment of Morton’s neuroma. ANZ Journal of Surgery.2010.  Retrospective study 37 patients with 38 neuromas failed conservative treatment. 63.1% complete/partial pain relief with RFA alone. 86.8% good results RFA with sx excision.     Restrepo-Garces et al. Pulsed Radiofrequency Under Ultrasound Guidance for Persistent Stump-Neuroma Pain. Pain Practice, vol 11, Issue 1, 2011.  Case report 45 y/o man with stump neuroma at distal site of AKA. PRF twice-42 degrees Celcius for 120 seconds-at proximal & distal ends of the neuroma. 90% decrease pain at 1,3 mths and 70% 6 months.    Moore et al. Radiofrequency Thermoneurolysis for the Treatment of Morton’s Neuroma. The Journal of Foot & Ankle Surgery. 2012.  Retrospective study 29 pts 32 neuromas. 24/29, 83% complete relief of symptoms, 5/29 minimal to no relief.    Graham et al. Ultrasound-guided radiofrequency ablation in the management of interdigital (Morton’s) neuroma. Skeletal Radiol. 2013.  30 neuromas, 25 patients 26/30 good outcome, 86.7% with 3 patients proceeding to surgical excision.   Cohen et al. Pulsed Radiofrequency Combined with Continuous Radiofrequency Ablation for the Treatment of Morton’s Neuroma: A Case Report. The Foot and Ankle Online Journal. 2013. 6(3):1  53 y/o woman with neuroma 2 & 3 interspace right foot 100% relief of symptoms   60 y/o female complaining of burning pain in the third interspace and around sinus tarsi right foot x 6 months, very sensitive to touch. Patient unable to wear closed in shoes.  s/p neurectomy 3IS & subtalar arthroesis x 2 right foot.  +Tinel’s superficial peroneal nerve  Diagnostic block of 1cc of 1% lidocaine plain of the superficial peroneal nerve at the sinus tarsi area rightcomplete resolution of pain.  Diagnosis: Stump neuroma 3IS right & entrapment of superficial peroneal nerve right.  Plan: Radiofrequency Ablation of stump neuroma 3IS and superficial peroneal nerve right foot.  Treatment PRF 42 degrees Celcius for 120 seconds CRF 90 degrees Celcius for 30 seconds At the point of maximal pain and 1 cm distal and 1 cm proximal.    Areas of Maximum Pain Probe in the Superficial Peroneal Nerve Probe in the Third Intermetatarsal Space Probe in the Third Intermetatarsal Space Fluoroscopic Image Confirming Position Fluoroscopic Image Distally Fluoroscopic Image DP View  Patient after 1 week had 50% decrease in symptoms.  Dorsal sensitivity over the neuroma scar was completely gone.  +Tinel’s over the superficial peroneal nerve.  Minimally invasive  Less recovery time  Less time in OR  Minimal to no side effects or disability  High success rates      Finney W, Wiener S, Catanzariti F. Treatment of Morton’s Neuroma Using Percutaneous Electrocoagulation. JAPMA 1989; Dec vol 79(12): 615-618. Tamimi M, McCeney M, Krutsch J. A Case Series of Pulsed Radiofrequency Treatment of Myofascial Trigger Points and Scar Neuromas. American Academy of Pain Medicine 2009; 10(6)1140-1143. Genon M, Chin T, Bedi H, Blackney M. Radio-frequency Ablation for the treatment of Morton’s neuroma. ANZ Journal of Surgery 2010; 583-585. Restrepo-Garces C, Marinov A, McHardy P, Faclier G, Avila A. Pulsed Radiofrequency Under Ultrasound Guidance for Persistent Stump-Neuroma Pain. Pain Practice 2011; 11(1) 98-102. Moore J, Rosen R, Cohen J, Rosen B. Radiofrequency Thermolysis for the Treatment of Morton’s Neuroma. The Journal of Foot & Ankle Surgery 2012;2022.     Chuter G, Chua Y, Connell D, Blackney M. Ultrasound-guided radiofrequency ablation in the management of interdigital (Morton’s) neuroma. Skeletal Radiology 2013; 42:107-111. Cohen J, Lenchig S. Pulsed Radiofrequency Combined with Continuous Radiofrequency Ablation for the Treatment of Morton’s Neuroma: A Case Report. The Foot and Ankle Online Journal March 2013; 6(3). Lee K, Kim J, Young K, Park Y, Kim J, Jegal H. Long-term results of neurectomy in the treatment of Morton’s neurma: more than 10 years’ follow up. Foot Ankle Spec 2011 Dec;4(6):349-53. Barrett S, Woolley M. Managing Morton’s Entrapment. Practical Pain Management. 2011;11(7)1-15.