A Comparison of Pain Management Protocols Following Total Knee Arthroplasty: Femoral Nerve Block versus Periarticular Injection of Liposomal Bupivacaine with an Adductor Canal Block.

BACKGROUND: Total knee arthroplasty (TKA) results in significant postoperative pain and a demanding postoperative path for recovery. This study was conducted to determine whether a femoral nerve block (FNB) or a periarticular injection of liposomal bupivacaine with an adductor canal block (LB+ACB) is superior for pain management. MATERIALS AND METHODS: A total of 557 consecutive primary TKA cases performed at a single hospital between 2010-2014 were retrospectively reviewed. After enrollment criteria were met, 390 cases remained (FNB=181, LB+ACB=209). Inpatient and post-discharge variables related to pain, narcotic use, healthcare resource utilization, and cost were compared. RESULTS: There were no significant differences in demographics between the two groups. There was also no significant difference in inpatient postoperative pain between the two groups. The FNB group consumed fewer narcotics overall compared to the LB+ACB group (p<0.001). However, the LB+ACB group experienced fewer opioid-related adverse events (p<0.001). The LB+ACB group had a shorter length of stay (p<.001), fewer readmissions (p=0.017) and reoperations (p=0.025), and lower costs (p<0.001). DISCUSSION: LB+ACB proved to be an equally effective postoperative TKA pain management tool compared to FNB while displaying superiority in other increasingly important areas such as length of stay and cost. The larger amount of narcotic consumption is a concern, however, and there may be a small population of patients for whom LB+ACB is not the best option.

Early return to function after hip resurfacing: is it better than contemporary total hip arthroplasty?

Our hypothesis was that return of function for young patients undergoing resurfacing total hip arthroplasty (THA) with metal-on-metal bearings or contemporary THA with ceramic bearings would be comparable. Results from 337 unilateral hip resurfacing patients were compared with results from 266 unilateral ceramic-on-ceramic THA patients. Early differences in Harris Hip Scores were observed, but all differences faded by 24 months. Hip resurfacing seems to be a viable alternative to THA for well-selected patients. However, the public perception of improved functional capabilities was not demonstrated in this patient population. Resurfacing patients may be more impaired (slightly higher pain scores/lower function scores) than their THA counterparts in the early postoperative period, but these differences disappear by 24 months when both groups report Harris Hip Scores in the excellent range.

Resurfacing arthroplasty for patients with osteonecrosis.

The suitability of third-generation metal-on-metal hip resurfacing products for patients with a primary diagnosis of osteonecrosis has been debated. The preservation of femoral head bone stock for femoral prosthetic support is essential for the long-term stability of implants. A modern hip resurfacing system was implanted in 1148 hips as part of a United States multicenter investigational device exemption study. Of these, 116 hips had a preoperative diagnosis of osteonecrosis and were compared to 1023 hips with osteoarthritis. Survival rates were not significantly different (95.9% and 95.8% at 24 months for osteoarthritis and osteonecrosis respectively, p = 0.46). Resurfacing arthroplasty for patients with osteonecrosis appears to be a reasonable alternative, taking into consideration implant size, patient gender, and size of femoral deficiency. Further characterization is needed to identify those specific patients with osteonecrosis for whom resurfacing arthroplasty would be appropriate.

Results and lessons learned from a United States hip resurfacing investigational device exemption trial.

BACKGROUND: Improvements in metal-on-metal bearings have made hybrid hip surface replacement a potential alternative for the young active patient with end-stage hip disease. Possible advantages include greater hip joint stability, bone preservation, and decreased osteolysis. In this study, we compared the clinical and radiographic results of a new resurfacing device with those in a historical group of standard total hip arthroplasties. METHODS: In 2001, the Cormet 2000 Hip Resurfacing Investigational Device Exemption study was initiated at twelve centers. A total of 337 patients treated with unilateral hip surface replacement with the Cormet device were enrolled in that study. These patients were compared with 266 patients in a previous study who had undergone unilateral total hip arthroplasty with ceramic bearing surfaces. Clinical and radiographic results were compared at similar time intervals. A newly recommended performance standard, the composite clinical success score, was used to assess non-inferiority of the hip resurfacing compared with the total hip arthroplasty used in the historical comparison population. RESULTS: At the time of follow-up, at a minimum of two years, the Harris hip scores were comparable between the resurfacing and total hip arthroplasty groups. Statistical evaluation of the composite clinical success scores confirmed the non-inferiority hypothesis. Revision was required in twenty-four patients in the resurfacing group and five patients in the total hip arthroplasty group. The most common cause of revision following resurfacing was failure of the femoral component (fracture of the femoral neck or loosening of the femoral component). CONCLUSIONS: Careful review of this study population revealed several important criteria for successful introduction of this resurfacing device into the United States. These include careful patient selection based on clinical and radiographic parameters and attention to various surgical details of implantation. These findings can be used to focus the training process for surgeons who wish to add implantation of this device to their surgical armamentarium. Such efforts should help to ensure safe and effective introduction of this new technology.