Distribution of sensation relating to the saphenous nerve.
The important infrapatellar branch of saphenous nerve
An important branch of the saphenous nerve relating to the knee is the infrapatellar branch which transmits sensation at the inner aspect and lower pole of the patella.
Peer-reviewed paper End of paper
Quotes from peer-reviewed paper:
"....Nerve injury of the saphenous nerve or infrapatellar branch seems to be a frequent complication following knee surgery or trauma...."
Citation: Krijgh DD, List EB, Teunis T, Bleys RLAW, Coert JH. The origin and course of the infrapatellar branch of the saphenous nerve: An anatomical study. JPRAS Open. 2022 Sep 5;34:144-151. doi: 10.1016/j.jpra.2022.08.006. PMID: 36304072; PMCID: PMC9593300.
What happens if the infrapatellar branch of saphenous nerve is cut?
This nerve is quite often damaged during surgery, leading to burning pains on the inner calf, 'pins and needles' in the same distribution and a feeling of muscle tightness.
Usually the patient can just be reassured and are only troubled for a short time.
Peer-reviewed paper End of paper Quick links
Quotes from peer-reviewed paper:
"There are many reports of....[infrapatellar branch of the saphenous nerve]....injury caused by surgery, especially knee arthroplasty, ....anterior cruciate ligament reconstruction, and incisions for anteromedial knee surgery...."
"....Problems can include loss of sensation, paresthesia, neuralgia, or hypersensitivity in the medial infrapatellar area of the lower extremity...."
Citation: Tan J, Wang X, Xiong F, Qian J, Ying Q, Mi J. Case report: A case of injury to the infrapatellar branch of the saphenous nerve caused by medial approach in knee arthroscopy. Front Neurol. 2023 Mar 3;14:1083871. doi: 10.3389/fneur.2023.1083871. PMID: 36937537; PMCID: PMC10020642.
What is a saphenous neuroma?
Very occasionally a damaged saphenous nerve desperately tries unsuccessfully to heal itself, and the tangled up ends form a small mass, called a neuroma.
A neuroma can become exquisitely sensitive and uncomfortable, with the symptoms persisting. A Tinel's test is usually positive. Local anaesthesia injection may immediately (but temporarily) relieve the symptoms and be diagnostic. MRI may also reveal the neuroma.
Local steroid injections may offer non-surgical resolution of symptoms, but sometimes a surgical neurectomy is needed.
Peer-reviewed paper
Quote from peer-reviewed paper:
"In the process of total knee arthroplasty (TKA), injury of the infrapatellar branch of the saphenous nerve (IBSN) or its terminal branches is common....Occasionally, a painful neuroma forms at the transection of the nerve, causing pain and limitation of the range of motion of the knee joint....[It] is not a widely known surgical complication. However it has been reported after anterior cruciate ligament reconstruction, arthroscopy, tibial nailing, and TKA...."
Citation: Xiang Y, Li Z, Yu P, Zheng Z, Feng B, Weng X. Neuroma of the Infrapatellar branch of the saphenous nerve following Total knee Arthroplasty: a case report. BMC Musculoskelet Disord. 2019 Nov 13;20(1):536. doi: 10.1186/s12891-019-2934-0. PMID: 31722713; PMCID: PMC6854730.