Analgesic efficacy of infrapatellar saphenous nerve block for outpatient knee arthroscopy

Arthroscopic surgery of the knee is a potentially painful procedure, which is
increasingly performed on an outpatient basis. Owing to the surgical access
route, block of the saphenous nerve may be well suited to provide postoperative
analgesia in day-care arthroscopic surgery, decreasing analgesic requirements
and hastening discharge.

The general aim of the present study is to test the efficacy of infrapatellar
saphenous nerve block as analgesic adjunct in patients undergoing out-patient
arthroscopic knee surgery. Our hypothesis is that saphenous nerve block leads
to improved postoperative pain therapy, and faster discharge from day-care
surgery.

Randomized, prospective, double-blind clinical trial. All patients will receive
standard anesthesia and analgesia. Patients in the intervention group will
receive additional saphenous nerve block.

Single shot ultrasound-guided saphenous nerve block.

We propose to perform a single shot nerve block of the purely sensory
end-branch Ramus infrapatellaris of the saphenous nerve under ultrasound
guidance. The risk of this intervention can be described as very low.
Following this, patients will undergo anesthesia and analgesia for arthroscopy
of the knee according to Departmental protocol.
Patients undergoing intervention treatment can expect substantially decreased
pain scores, and less need for pain medication, thereby potentially decreasing
iatrogenic side-effects such as nausea and vomiting. The expected net effect is
a faster recovery, enhanced patient satisfaction, and faster discharge from
day-care surgery.