Development and validation of a new method for locating patella sensory nerves for the treatment of inferior and superior knee pain

Abstract

BackgroundRadiofrequency ablation and percutaneous cryoneurolysis to relieve knee pain requires treating large areas to ensure coverage due to high variability in the sensory innervation of the knee and limitations of current methods for defining treatment targets. This study sought to define and validate a new treatment approach targeting the major sensory nerves of the superior patella and expand upon previous work to define a more efficient treatment approach targeting the sensory nerves of the inferior patella.MethodsTranscutaneous electrical nerve stimulation and ultrasound were used to evaluate the location and relationship of the cutaneous nerves to the superior and inferior aspects of the knee in 25 healthy volunteers. Using information derived from these evaluations, investigators defined new linear target treatment areas, or treatment lines, using anatomical landmarks, which were validated against locations of sensory nerves through cadaveric dissection of 15 fresh specimens.ResultsThe proposed treatment lines captured the vast majority of nerve branching variations during cadaveric validation.ConclusionThis study defined treatment lines, identifiable using only anatomical landmarks, which effectively target the nerves responsible for superior and inferior knee pain and reduce the total treatment area and procedure time when administering treatments such as radiofrequency ablation and cryoneurolysis.

Novel cryoneurolysis device for the treatment of sensory and motor peripheral nerves

“…In this study, the IPBSN was located using anatomical landmarks [54]. Subsequently, a method for locating the anterior femoral cutaneous nerve (AFCN), which innervates the anterior superior part of the knee capsule and may offer additional postoperative relief, was defined and validated in a cadaveric model [64].…”

“…A small proof-of-concept study (n = 10) was carried out to examine the effect of cryoneurolysis of the IPBSN for the treatment of chronic knee pain due to osteoarthritis using anatomical landmarks [63,64]. After treatment with the iovera°system (Myoscience, Fremont, CA, USA), the average pain scores (NRS) decreased from a baseline of 6 to 1, 2, and 2 after 0, 7, and 30 days, respectively.…”

Cryoneurolysis for the management of chronic pain in patients with knee osteoarthritis; a double-blinded randomized controlled sham trial

“…Radiographic confirmation and clinical determination of knee OA as pain generator followed by the identification of the infrapatellar branch of the saphenous nerve (IBSN) and anterior femoral cutaneous nerve (AFCN). Predefined areas for each nerve are marked directly on the patient [ 35 , 36 ]. The area is searched using a transcutaneous electrical nerve stimulation (TENS) wand.…”

Novel Methodologies in Regional Anesthesia for Knee Arthroplasty

“…4). 32 Both nerves provide purely sensory innervation to the anterior aspect of the knee and lie in a predictable and superficial location in the proximity of the knee capsule. The anterior femoral cutaneous nerve innervating the superior knee lies within the fascia above the quadriceps tendon as it crosses a horizontal line the width of the patella approximately 7 cm above the superior aspect of the patella.…”

“…34 The associated prolonged total sensory, motor, and proprioception block combined with an unpredictable duration of action (weeks to months) is not appropriate in most clinical scenarios involving acute pain with the one potential exception being the treatment of the anterior femoral cutaneous and infrapatellar branch of the saphenous nerve for knee surgery, such as knee arthroplasty. 18,32 Similar to traditional needle-based percutaneous regional anesthesia techniques, potential complications of cryoneurolysis include bleeding, bruising, and infection. Additional risks include injury to the nerve or surrounding tissue if the cannula is retracted before resolution of the ice ball, and cutaneous discoloration if the ice ball reaches the skin.…”