What are the causes of foot drop (peroneal nerve palsy)?

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From the Research

Flail foot is primarily caused by damage to the peroneal nerve, which can result from various factors including traumatic injuries, compression, diabetes-related neuropathy, and systemic conditions. The most common causes of flail foot include:

  • Traumatic injuries such as fractures or dislocations around the knee or fibular head
  • Compression from prolonged pressure, like leg crossing or tight casts
  • Diabetes-related neuropathy
  • Systemic conditions like Guillain-Barré syndrome or multiple sclerosis
  • Direct nerve injuries during surgery, particularly knee operations Less commonly, tumors or cysts compressing the nerve pathway, vitamin deficiencies (particularly B vitamins), and certain medications with neurotoxic side effects may cause this condition 1, 2. The peroneal nerve is particularly vulnerable to injury due to its superficial location as it wraps around the fibular head. When damaged, patients lose the ability to lift their foot, resulting in a characteristic foot drop where the toes drag during walking, often requiring compensatory movements like high-stepping to avoid tripping. According to a study published in 2021, peripheral neuropathy in the lower limbs of individuals with spinal cord injury or disease is a significant concern, with a length-dependent polyneuropathy diagnosed in 0.77% of all admissions 3. Treatment depends on identifying and addressing the underlying cause, potentially including physical therapy, bracing, and in some cases, surgical intervention, as seen in a study from 2018 where limited surgeries combined with external fixation played an important role in recovering the stability of foot and ankle, with better clinical results and less complications 4. In real-life clinical practice, a meticulous neurological evaluation and targeted diagnostic testing are necessary to ascertain the site of the lesion and establish the degree of damage, as highlighted in a 2008 study 1. Overall, the management of flail foot should prioritize the identification and treatment of the underlying cause, with a focus on improving patient outcomes and quality of life.

References

Research

Foot drop: where, why and what to do?

Practical neurology, 2008

Research

Neurologic Disorders Affecting the Foot and Ankle.

Clinics in podiatric medicine and surgery, 2022

Research

[Treatment strategy for flail foot with sensory disorder of spina bifida sequela in adult].

Zhongguo xiu fu chong jian wai ke za zhi = Zhongguo xiufu chongjian waike zazhi = Chinese journal of reparative and reconstructive surgery, 2018

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This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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