BACKGROUND Neuropathy of the common peroneal nerve caused by compression by a fabella is an extremely rare form of compression neuropathy.Involving both the superficial and deep peroneal nerves,it usually manifests as...BACKGROUND Neuropathy of the common peroneal nerve caused by compression by a fabella is an extremely rare form of compression neuropathy.Involving both the superficial and deep peroneal nerves,it usually manifests as either impaired sensation from the lower lateral leg to the top of the foot or drop foot,or as a combination of both.CASE SUMMARY We report the case of a 58-year-old Asian female who presented with inversion of the right foot during the stance phase of gait without sensory complaints related to the lower leg.Electrodiagnostic testing revealed the neuropathy of the common peroneal nerve at the level of the knee,exclusively affecting the muscular branch of the superficial peroneal nerve.A neuromuscular ultrasound disclosed swelling of the right common peroneal nerve just before it crossed over a large fabella as well as atrophy and fatty infiltration of the right peroneus longus and peroneus brevis muscles.Surgical excision of the fabella and neurolysis were performed.Subsequently,the strength of the right foot evertors improved,but the unsteady gait with occasional falls persisted for nine months after the surgery.Therefore,another procedure was performed to transfer the split posterior tibialis tendon to the peroneus brevis in order to correct the gait.CONCLUSION This is the first case of neuropathy of the common peroneal nerve caused by compression by a fabella affecting exclusively the muscular branch of the superficial peroneal nerve.Clinicians should be aware of this unusual peripheral neuropathy while evaluating and treating patients with gait disturbance.展开更多
Background: Fabella is a natural occurring sesamoid bone, cartilage or a mixture of both that is usually located at the posterolateral corner (PLC) of the knee [1]. Recently the PLC of the knee has been extensively in...Background: Fabella is a natural occurring sesamoid bone, cartilage or a mixture of both that is usually located at the posterolateral corner (PLC) of the knee [1]. Recently the PLC of the knee has been extensively investigated because it is a common site of injuries and diseases [2] [3]. The complexity of PLC anatomy needs to be fully understood because the fabella could be missed diagnosis as an osteochondral defect, osteochondritis dissecans (OCD), calcific tendinitis, or foreign body. We present a case report of fabella syndrome triggered by trauma and also performed a review of literature for the various diagnoses that might be confused with fabella syndrome. Case presentation: A 29-year-old, Sudanese male presented to the trauma center in King Khalid Hospital in KSA, complaining of pain and partial swelling in his left knee joint due to trauma. Fabella was detected in the posterior lateral corner (PLC) of the knee joint embedded in the lateral head of the gastrocnemius muscle. All other pathological conditions were excluded. Conclusion: Fabella is sesamoid bone with variable size, found in the PLC. Commonly if present it causes periodic pain especially in the fully extended knee or it remains asymptomatic. Trauma, surgery, sports or heavy extreme activities may trigger the pain of asymptomatic fabella. Clinicians should consider that pain in the PLC of the knee can result from the presence of the fabella in a condition called fabella syndrome.展开更多
基金Supported by the National Cheng Kung University Hospital,Taiwan,No.NCKUH-11210036.
文摘BACKGROUND Neuropathy of the common peroneal nerve caused by compression by a fabella is an extremely rare form of compression neuropathy.Involving both the superficial and deep peroneal nerves,it usually manifests as either impaired sensation from the lower lateral leg to the top of the foot or drop foot,or as a combination of both.CASE SUMMARY We report the case of a 58-year-old Asian female who presented with inversion of the right foot during the stance phase of gait without sensory complaints related to the lower leg.Electrodiagnostic testing revealed the neuropathy of the common peroneal nerve at the level of the knee,exclusively affecting the muscular branch of the superficial peroneal nerve.A neuromuscular ultrasound disclosed swelling of the right common peroneal nerve just before it crossed over a large fabella as well as atrophy and fatty infiltration of the right peroneus longus and peroneus brevis muscles.Surgical excision of the fabella and neurolysis were performed.Subsequently,the strength of the right foot evertors improved,but the unsteady gait with occasional falls persisted for nine months after the surgery.Therefore,another procedure was performed to transfer the split posterior tibialis tendon to the peroneus brevis in order to correct the gait.CONCLUSION This is the first case of neuropathy of the common peroneal nerve caused by compression by a fabella affecting exclusively the muscular branch of the superficial peroneal nerve.Clinicians should be aware of this unusual peripheral neuropathy while evaluating and treating patients with gait disturbance.
文摘Background: Fabella is a natural occurring sesamoid bone, cartilage or a mixture of both that is usually located at the posterolateral corner (PLC) of the knee [1]. Recently the PLC of the knee has been extensively investigated because it is a common site of injuries and diseases [2] [3]. The complexity of PLC anatomy needs to be fully understood because the fabella could be missed diagnosis as an osteochondral defect, osteochondritis dissecans (OCD), calcific tendinitis, or foreign body. We present a case report of fabella syndrome triggered by trauma and also performed a review of literature for the various diagnoses that might be confused with fabella syndrome. Case presentation: A 29-year-old, Sudanese male presented to the trauma center in King Khalid Hospital in KSA, complaining of pain and partial swelling in his left knee joint due to trauma. Fabella was detected in the posterior lateral corner (PLC) of the knee joint embedded in the lateral head of the gastrocnemius muscle. All other pathological conditions were excluded. Conclusion: Fabella is sesamoid bone with variable size, found in the PLC. Commonly if present it causes periodic pain especially in the fully extended knee or it remains asymptomatic. Trauma, surgery, sports or heavy extreme activities may trigger the pain of asymptomatic fabella. Clinicians should consider that pain in the PLC of the knee can result from the presence of the fabella in a condition called fabella syndrome.