Femoral nerve block (FNB) is a popular, minimally invasive postoperative pain management procedure following total knee arthroplasty (TKA). Prolonged motor blockade has been associated with increased risk of fall. The primary objective of the present study was therefore, to evaluate the risk of falling or near falling for FNB in patients who underwent TKA.

After Institutional Review Board approval, prospective cohort (142) of patients was randomized into two groups: the intervention (FNB as an adjunct to analgesia) vs the control (standard treatment) at our hospital for unilateral primary conventional TKA. The risk of falling as assessed using Tinetti Gait and Balance Instrument and Timed Up and Go (TUG) test was evaluated on the day of hospital discharge, and 1, 2, and 3 months after TKA. All data were collected and critically analyzed and p < 0.05 was considered statistically significant.

Patients in FNB group displayed significant low visual analog scale (VAS) scores than control (p < 0.05). Thirty-seven patients (26.05%) reported falls in the 3 months after surgery. Patients who received FNB following TKA experienced an expected significant worsening of physical function and had increased risk of falling as evaluated by TUG test and Tinetti Gait and Balance Instrument (p < 0.05). Due to unexpected fall, eight patients (28.57%) in FNB group sustained periprosthetic fractures and two patients (22.2%) in control group had opening of arthrotomy. At 3 months, 55 patients in FNB group had reported postoperative neuritis. Significant delay in rehabilitation and early ambulation in patients received FNB, which in turn increases the risk of prolonged hospitalization (p < 0.05).

The Tinetti and gait index and TUG test time showed increased risk of fall for the patients who received FNB owing to substantial functional deficits.

Shah VI, Upadhyay S, Shah K, Sheth AN, Kshatriya A, Jain A, Sharma P, Sanandia JG. Risk of Falling after Femoral Nerve Block for Total Knee Arthroplasty: Periprosthetic Fractures—A Serious Concern. J Recent Adv Pain 2017;3(3):125-130.