A 78-year-old woman is evaluated in a skilled nursing facility due to weakness. She recently had a prolonged hospitalization for exacerbation of chronic obstructive pulmonary disease and required mechanical ventilation in the intensive care unit due to respiratory failure. When the patient was transferred to the skilled nursing facility she was unable to rise from a chair due to profound deconditioning. She is now able to stand but has fallen twice during physical therapy. Medical history is notable for peripheral artery disease, type 2 diabetes mellitus, and moderate dementia.
On examination, the patient has diminished light touch sensation at the right lateral leg and dorsal surface of the right foot. The right foot also shows weakness of dorsiflexion and eversion. Knee reflexes are normal and symmetric, but ankle reflexes are absent bilaterally. While ambulating with a walker, the patient drags her right toes and slaps her right foot to the ground awkwardly.
Which of the following is the most appropriate next step in management of this patient's weakness?

Question

A 78-year-old woman is evaluated in a skilled nursing facility due to weakness.  She recently had a prolonged hospitalization for exacerbation of chronic obstructive pulmonary disease and required mechanical ventilation in the intensive care unit due to respiratory failure.  When the patient was transferred to the skilled nursing facility she was unable to rise from a chair due to profound deconditioning.  She is now able to stand but has fallen twice during physical therapy.  Medical history is notable for peripheral artery disease, type 2 diabetes mellitus, and moderate dementia.
On examination, the patient has diminished light touch sensation at the right lateral leg and dorsal surface of the right foot.  The right foot also shows weakness of dorsiflexion and eversion.  Knee reflexes are normal and symmetric, but ankle reflexes are absent bilaterally.  While ambulating with a walker, the patient drags her right toes and slaps her right foot to the ground awkwardly.
Which of the following is the most appropriate next step in management of this patient's weakness?

Quizplus · Accepted Answer

11ec193a_9728_7048_853d_9dddb02515bf_MD0002_00 This patient has a foot drop and steppage gait. Together with diminished sensation at the lateral leg and foot, this suggests a common peroneal nerve injury. The common peroneal nerve courses around the proximal fibula in the leg, where it is exposed to external compressive injury. Risk factors include prolonged hospitalization, trauma (eg, car versus pedestrian traffic incident), and leg casting. Patients without any obvious causes should be queried for behavioral factors (eg, habitual leg crossing) that may contribute. common peroneal nerve The diagnosis of peroneal nerve palsy is primarily based on clinical features, although nerve conduction studies can confirm the diagnosis. Most patients respond to physical therapy measures and an ankle foot orthotic to facilitate ambulation. Surgical decompression can help in cases with ongoing structural compression but is not usually needed. (Choice A) Stroke is a less common cause of foot drop and typically occurs in patients with residual hemiparesis. This patient has loss of sensation in the common peroneal distribution. (Choice B) Guillain-Barré syndrome causes a progressive, symmetric, ascending weakness with paresthesias and loss of reflexes. This patient's symmetric loss of only ankle reflexes is common in the elderly and does not suggest specific pathology. The unilateral weakness in the distribution of a single nerve makes Guillain-Barré unlikely. (Choice D) L4-5 disc herniation can cause foot drop but is usually associated with back pain. (Choice E) Vitamin B₁₂ deficiency causes an ataxic, wide-based gait with impaired balance, and neuropathy is generally symmetric and slowly progressive rather than focal and acute as seen in this patient. ₁₂ Educational objective: Injury to the common peroneal nerve causes loss of sensation at the lateral leg and foot. Motor findings include foot drop and a steppage gait. Risk factors include prolonged hospitalization, trauma, and leg casting. Initial treatment for foot drop due to common peroneal nerve injury includes physical therapy and an ankle foot orthotic. __________ References: Foot drop: where, why and what to do? (http://www.ncbi.nlm.nih.gov/pubmed/18502948) Peroneal nerve palsy: evaluation and management. (http://www.ncbi.nlm.nih.gov/pubmed/26700629)

A 78-Year-Old Woman Is Evaluated in a Skilled Nursing Facility