Human chondrocyte viability after treatment with local anesthetic and/or magnesium: results from an in vitro study.
OBJECTIVE
We aimed to assess the effect on chondrocyte viability of adding magnesium to a variety of commonly available local anesthetic agents.


METHODS
Human chondrocytes were grown under standard culture conditions. Cells were exposed to a local anesthetic agent with the addition of magnesium (10%, 20%, or 50%). Cells were also exposed to the varying concentrations of magnesium and 0.9% saline solution. Untreated cells served as controls. The CellTiter 96 AQueous One Solution Cell Proliferation Assay was used to assess for cell viability 24 hours after exposure. One-way analysis of variance was used to test for statistical significance.


RESULTS
Magnesium sulfate alone was no more toxic than normal saline solution (P > .3) compared with untreated cells. The addition of magnesium to the local anesthetic agents resulted in greater cell viability than when cells were treated with a local anesthetic alone (lidocaine [P = .033], levobupivacaine [P = .007], bupivacaine [P < .001], and ropivacaine [P < .001]).


CONCLUSIONS
Our findings support the use of magnesium either alone or in combination with a local anesthetic rather than a local anesthetic alone, and this represents a potential strategy for the reduction of chondrocyte toxicity associated with intra-articular local anesthetic administration after arthroscopy.


CONCLUSIONS
The addition of magnesium to a local anesthetic results in a reduced toxic effect to the articular chondrocyte. This may represent a potential approach to intra-articular analgesia.
School of Medicine and Medical Sciences, University College Dublin, Dublin, Ireland. joseph.f.baker@gmail.com
Joseph F
JF
Baker
Damien P
DP
Byrne
Pauline M
PM
Walsh
Kevin J
KJ
Mulhall
D000577:Amides / Q000494:pharmacology / Q000633:toxicity; D000779:Anesthetics, Local / Q000494:pharmacology* / Q000633:toxicity; D002045:Bupivacaine / Q000031:analogs & derivatives / Q000494:pharmacology / Q000633:toxicity; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D019902:Chondrocytes / Q000166:cytology / Q000187:drug effects*; D006801:Humans; D000077554:Levobupivacaine; D008278:Magnesium Sulfate / Q000494:pharmacology*; D000077212:Ropivacaine
D000577:Amides; D000779:Anesthetics, Local; D008278:Magnesium Sulfate; D000077212:Ropivacaine; D000077554:Levobupivacaine; D002045:Bupivacaine