Prospective Randomized Trial Comparing Femoral Nerve Block With Intraoperative Local Anesthetic Injection of Liposomal Bupivacaine in Total Knee Arthroplasty.

BACKGROUND: Postoperative pain after total knee arthroplasty (TKA) may impact long-term results and incidence of complications. Femoral nerve block (FNB) provides excellent pain relief after TKA, although associated risks include weakness, delayed participation in therapy, and nerve injury. Liposomal bupivacaine (LB) is a potentially longer acting local anesthetic that may reduce postoperative pain. METHODS: We performed a prospective, randomized, double-blind study of 373 TKA patients randomized to receive either an FNB (control group), or an intraoperative periarticular injection (PAI) with LB and a placebo saline FNB (experimental group). Patients were evaluated with visual analog scores for pain, range of motion, performance of straight leg raise (SLR), walking distance, and Short Form-12 up to 1 year postoperatively. RESULTS: Twelve and 24 hours postoperatively, the control group had significantly lower pain scores (mean 3.24 vs 3.87; P = .02) and higher range of motion (84.54° vs 78°; P < .001). The patients receiving LB PAI were significantly more likely to perform a straight leg raise 12 hours postoperatively (73% vs 50%; P = .0003). Patients in the LB (experimental) group scored better in the physical function component of the Short Form-12 (-23 vs -27, P = .01) 3 months postoperatively. CONCLUSION: While pain scores were slightly lower in the control group in the first 24 hours after TKA compared with LB PAI, the magnitude of the difference was small, and excellent pain relief was provided by both interventions. Use of LB PAI in TKA is a reasonable alternative to FNB, which avoids the additional weakness and other risk associated with FNB procedures.

High Rate of Early Revision After Custom-Made Unicondylar Knee Arthroplasty.

BACKGROUND: There has been a recent interest in custom-made partial knee arthroplasties to provide patient-specific instrumentation and better fit of the prosthesis. While unicondylar knee arthroplasties (UKAs) have demonstrated good outcomes and durable results in many studies, there is little evidence on outcomes of these custom-made implants. METHODS: We performed a retrospective review of all custom-made UKAs performed at our institution by one surgeon from 2008 to 2015. We analyzed preoperative demographics, clinical follow-up evaluations, and radiographs and performed an analysis of risk factors including age, gender, height, weight, body mass index, and tibial insert thickness. The incidence of revision surgery, radiographic failures indicating component loosening, and symptomatic clinically failed implants was calculated at an average of 54.0 months of follow-up. RESULTS: We analyzed 115 consecutive custom-made medial UKAs from a single surgeon at our institution and found 29 (25.2%) UKAs had failed at an average of 33.1 months after surgery. Reasons for failure included aseptic femoral loosening (10), aseptic tibial loosening (8), loosening of both components (4), infection (3), progression of osteoarthritis (2), pain (1), and dislodged polyethylene insert (1). We found a significant relationship between implant failure and body mass index; no other study variables were statistically significant. CONCLUSION: We found a relatively high rate of aseptic loosening and particularly femoral component loosening in the short- to intermediate-term follow-up period. While further study of larger numbers of custom-made UKA from multiple institutions may help verify these findings, we recommend careful consideration of the use of this implant.

Rural/urban differences in discharge from rehabilitation in older adults with traumatic brain injury.

BACKGROUND/OBJECTIVES: Rates of traumatic brain injury (TBI) among older adults and treatment of this population in nursing homes are increasing. The objective of this study is to examine differences in the quality of care and outcomes of older adults with TBI in rural and urban settings by (1) comparing the rates of successful community discharge; and (2) reasons for not achieving successful discharge among patients in rural and urban environments. DESIGN: Retrospective national cohort study of skilled nursing facility (SNF) patients using Medicare inpatient claims linked with Minimum Data Set assessments. Demographic, health, and facility characteristics were compared between rural and urban settings using descriptive statistics. Logistic regression with state random effects was used to identify characteristics that predicted successful discharge. SETTING: U.S. skilled nursing facilities (n = 11,771). PARTICIPANTS: Medicare beneficiaries aged 66 and older discharged to a SNF following hospitalization for TBI between 2011 and 2015 (n = 61,021). MEASUREMENTS: Successful community discharge defined as discharge from SNF within 100 days of admission and remaining in the community for ≥30 days without dying or admission to an inpatient healthcare facility. RESULTS: Unadjusted rates of successful discharge were significantly lower for patients in rural settings compared with patients in urban settings (52.1% vs 58.5%, p < 0.01). Patients in rural settings had lower adjusted odds (odds ratio 0.84, 95% confidence interval = 0.80-0.89) of successful discharge. Reasons for not discharging successfully differed between rural and urban settings with rural patients less likely to discharge from SNF within 100 days though also less likely to be rehospitalized within 30 days of SNF discharge. CONCLUSION: Given the low overall rate of successful community discharge and worse outcomes among rural patients, further research to explore interventions to improve SNF care and discharge planning in this population is warranted.

Intraoperative Proximal Tibia Periprosthetic Fractures in Primary Total Knee Arthroplasty.

Intraoperative fracture of the proximal tibia is a rare complication of total knee arthroplasty (TKA) with few studies available reporting risk factors or prognosis. A review of our prospective joint registry was performed to determine the incidence and associated risk factors of intraoperative tibia fractures during primary TKA; 14,966 TKAs of all manufacturers were performed with 9 intraoperative tibia fractures. All fractures occurred in a single TKA design. There were 8,155 TKAs of this design performed with a fracture incidence of 0.110%. All but one fracture occurred on the medial tibial plateau, and all but one occurred during preparation of the tibia with keel punching. A control group of 75 patients (80 knees) with the same TKA design were randomly selected. Baseplates size 3 or smaller were less likely to experience an intraoperative fracture (odds ratio [OR]: 0.864, 95% confidence interval [CI]: 0.785-0.951), as were knees with a polyethylene insert thickness of 13 mm or larger (OR: 0.882, 95% CI: 0.812-0.957). Fractures were treated with a variety of different methods, but every patient had at least one screw placed and most (67%) had postoperative weight-bearing restrictions. At final follow-up, there were no cases of nonunion, component subsidence, or need for reoperation. Intraoperative tibia fractures are a rare complication of this TKA design at 0.11%. Knees with baseplates of size ≤3 and polyethylene thickness ≥13 mm were less likely to experience intraoperative fracture. These findings may be related to the depth of tibial resection, requiring the use of a thicker polyethylene insert, and a change in the keel width in implants size 4 or larger. No fracture patients required reoperation.

Incidence and Risk Factors for Posterior Cruciate Ligament Avulsion during Cruciate Retaining Total Knee Arthroplasty.

During cruciate retaining (CR) total knee arthroplasty (TKA), the posterior cruciate ligament (PCL) may avulse at its insertion. The incidence of PCL avulsion fracture has not been previously studied. The aim of this study is to report on the incidence and clinical significance of intraoperative PCL avulsion during primary CR TKA and to identify potential risk factors. Our institutional joint registry was retrospectively reviewed for PCL avulsion occurring during CR TKA implanted between April 2008 and April 2016. Patient demographics, preoperative range of motion (ROM), complications, and revision rate were examined. A control group of 132 patients was used for comparison to identify potential risk factors. Forty-four of 2,457 patients (1.7%) suffered a PCL avulsion fracture during primary CR TKA. No intraoperative repair was performed and no postoperative weight bearing or ROM restrictions were implemented. There was no significant difference in BMI (p = 0.258), mean preoperative ROM (p = 0.763), or femoral and tibial component sizes (p = 0.3069, p = 0.1306) between groups. Logistic regression found female gender (p = 0.0254) to be the only statistically significant risk factor for PCL avulsion. The incidence of intraoperative PCL avulsion fracture during CR TKA is low (1.7%) and does not appear to affect postoperative ROM, subjective stability, or incidence of revision. Female gender was identified as the only patient factor that increased the risk of PCL avulsion fracture.