Ischemic Monomelic Neuropathy: The Case for Reintroducing a Little-Known Term

Abstract

Ischemic monomelic neuropathy (IMN) is a little-known, painful axonal neuropathy, secondary to vascular occlusion or steal phenomenon. It typically occurs after vascular bypass, hemodialysis fistulization, or diabetic microvascular disease in the absence of significant clinical features of ischemia. There is limited literature to assist in the characterization and diagnosis of this condition. We describe three patients with IMN with no surgical or peripheral vascular disease history who exhibited spontaneous, persistent foot pain, edema numbness, and weakness with denervation on needle electromyogram in a distal lower leg peripheral nerve distribution. Occlusive disease was found in all patients on angiogram, requiring vascular bypass surgery.

Progressive unilateral leg weakness after lumbar decompression due to ischemic monomelic neuropathy misdiagnosed as epidural hematoma: A CARE-compliant case report

“…Previous studies reported that symptoms induced by IMN are reversible. [ 5 , 10 , 11 ] Rapid diagnosis and treatment are of particular importance for preventing irreversible nerve injury and maximizing neurological recovery. The delayed diagnosis and treatment of IMN can result in poor outcomes.…”

“…[ 4 ] In rare cases of acute arterial occlusion, ischemic axonal mononeuropathies in the affected limb manifest without significant skin or muscle involvement. [ 5 ] This is known as ischemic monomelic neuropathy (IMN). [ 5 ]…”

“…[4] In rare cases of acute arterial occlusion, ischemic axonal mononeuropathies in the affected limb manifest without significant skin or muscle involvement. [5] This is known as ischemic monomelic neuropathy (IMN). [5] After lumbar spine surgery, motor weakness in the lower extremities occasionally occurs as a postoperative complication.…”

Spontaneous ischemic neuropathy of the sciatic nerve due to arterial occlusion – a rare cause of acute neuropathy not to be missed, a report of two cases

“…Spontaneous arterial ischemia with secondary axonal nerve damage due to occlusive vascular disease had been first described under the term “ischemic neuritis” in 1949 [ 10 , 11 ]. Later the term ischemic monomelic neuropathy (IMN) was introduced by Wilburn et al in 1983 [ 12 ] and recently discussed in a report of three cases [ 13 ]. Ischemic monomelic neuropathy has been originally described as a non-compressive occlusion of blood supply or steal phenomenon causing single or multiple axonal mononeuropathies in the distal limb, without necrosis of muscles or skin [ 12 ].…”

“…Classical features of limb ischemia such as intermittent ischemic claudication, paleness and swelling of the limb and clinical evidence of necrosis are typically absent and pulses may be palpable [ 12 ]. Therefore, a significant and detrimental delay in diagnosis may occur with patients misdiagnosed with lumbar radiculopathy [ 12 ] or even complex regional pain syndrome [ 13 ].…”