June 2016 Video Challenge: Subacute Severe Pelvis and Anterior Thigh Pain

Diabetic Amyotrophy
- Diabetic amyotrophy (diabetic lumbosacral radiculoplexus neuropathy) is a characteristic syndrome that mostly affects diabetic patients and constitutes about one percent of diabetic neuropathies.
- Diabetic neuropathies are grouped into two main categories according to their pathology:
         • Metabolic/ischemic mechanisms explain the most common distal sensory diabetic neuropathy.
         • Microvasculitis explains diabetic amyotrophy and diabetic third cranial nerve palsy.
- The second category is pathologically characterized by microvasculitis and unlike the former one it usually occurs in well controlled diabetes mellitus with minimal end organ damage (retinopathy, nephropathy)
- Other causes of thigh pain in diabetic patients should be considers, including:
         • L3 radiculopathy: L3 nerve root is not a common target for degenerative spine disease but it can lead to severe anterior thigh pain.
         • Diabetic muscle infarction: This usually affects the quadriceps muscles and presents with pain and indurated swelling in the anterior thigh. An MRI of the area shows infarction of the muscle.
         • Meralgia paresthetica: Severe lateral thigh pain due to entrapment of the lateral femoral cutaneous nerve is common in diabetic patients. Knee jerk and quadriceps strength are preserved.
- Diabetic amyotrophy may be as benign as a transient thigh pain that does not even reach the attention of the physician.
         • However, more than a third of cases are bilateral and 15 percent of cases lead to bilateral foot drop, while 12 percent of cases spread to the arms (diabetic thoracoabdominal radiculopathy).
- The progression of pain and weakness despite good diabetes control causes significant frustration.
- Lumbar surgery is frequently performed due to the presence of incidental LS degenerative spine disease.
- Most cases regain significant strength, but it may take a year for recovery to start and two years to be maximum.