Sports Medicine
Nazia Hossain, MD
Resident Physician
University of Miami Physical Medicine & Rehab
Miami, Florida, United States
Timothy Tiu, MD
Associate Professor
University of Miami
Miami, Florida, United States
Nazia Hossain, MD
University of Miami Physical Medicine & Rehab
Miami, Florida, United States
Iatrogenic saphenous neuropathy s/p arthroscopic surgery
Case Description:
A 23 year old male presented with right medial infrapatellar pain after an arthroscopic patellar chondroplasty and partial synovectomy 5 years prior. He originally had retropatellar pain after a soccer collision and underwent surgery after failing conservative management for a patellar cartilage fissure. He has since had multiple interventions by different providers including an ultrasound-guided saphenous nerve block in the adductor canal, patellar tendon scraping, infrapatellar nerve block, two fluoroscopy-guided genicular nerve blocks, multiple landmark-based steroid and platelet-rich plasma injections, and a repeat patellar chondroplasty and partial synovectomy, but with plica excision. He had minimal relief from these interventions.
Diagnostic ultrasound revealed a thickened medial retinaculum and associated enlargement of a terminal branch of the infrapatellar branch of the saphenous nerve near the portal site. Hydrodissection with a 1:1 ratio of lidocaine 1% and dextrose 10% was performed directly targeting this small branch and the patient reported immediate pain relief.
This case highlights how a detailed history, physical and diagnostic ultrasound can allow for precise intervention and thereby reduce the risk of iatrogenic injury and unnecessary surgery.
Discussions: Through a detailed history and diagnostic ultrasound, we were able to avoid interventions that had already failed and tailor the injection to the specific nerve branch causing the patient’s pain, thereby reducing the risk of further iatrogenic injury. Also, it is important to note that though the patient had a previous general infrapatellar nerve block, variations in technique and provider experience can lead to different outcomes such as in this case. Ultrasound-guided interventions are a great tool in the arsenal for treating chronic knee pain and further targeting injections based on patient pain and symptoms can provide increased benefit.
Conclusions:
