Planovalgus Foot Deformity in Patients Undergoing Total Hip Arthroplasty Is Associated With Increased Risk of Falls, Implant-Related Complications, and Revisions: A Case-Control Analysis.

BACKGROUND: Pes planus occurs due to the loss of the longitudinal arch of the foot, resulting in altered gait mechanics. This may lead to increased complications following total hip arthroplasty (THA). Thus, the aim of this study was to assess the effects that pes planus has on rates of falls, implant complications, fall-related injuries, and times to revision among THA patients. METHODS: A retrospective review of a private insurance claims database was conducted from 2010 to 2021. Patients who had a diagnosis of congenital or acquired pes planus and cases of THA were identified. Patients undergoing THA with a diagnosis of pes planus were matched to control patients 1:5 based on age, sex, and comorbidity profiles. Logistic regression was utilized to assess for differences in complication rates. RESULTS: A total of 3,622 pes planus patients were matched to 18,094 control patients. The pes planus group had significantly higher rates of falls than the control group (6.93 versus 2.97%, OR [odds ratio]: 2.43; CI [confidence interval]: 2.09 to 2.84; P < .001). Pes planus patients also had significantly greater odds of dislocation (OR: 1.89; CI: 1.58 to 2.27; P < .001), mechanical loosening (OR: 2.43; CI: 2.09 to 2.84; P = .019), and periprosthetic fracture (OR: 2.43; CI: 2.09 to 2.84; P < .001). The pes planus group had significantly greater rates of proximal humerus fractures (P = .008), but no difference was seen in distal radius fractures (P = .102). The time to revision was significantly shorter in the pes planus group (190 versus 554 days, P < .001). CONCLUSIONS: Pes planus in patients undergoing THA is associated with increased risk of complications and faster time to revision. These findings may allow orthopaedic surgeons to identify those patients at risk and allow for more educated patient counseling and operative planning.

Risk of Periprosthetic Joint Infection After Intra-Articular Corticosteroid Injection Following Unicompartmental Knee Arthroplasty.

BACKGROUND: Perioperative intra-articular joint injection is a known risk factor for developing prosthetic joint infection (PJI) in the immediate preoperative and postoperative periods for total knee arthroplasty, but is less defined in unicompartmental knee arthroplasty (UKA). The goal of this study was to elucidate the risk of developing PJI after intra-articular corticosteroid injection (IACI) into a post UKA knee. METHODS: A retrospective review of a nationwide administrative claims database was performed from January 2015 to October 2020. Patients who underwent UKA and had an ipsilateral IACI were identified and matched 2:1 to a control group of primary UKA patients who did not receive IACI. Multivariate logistic analyses were conducted to assess differences in PJI rates at 6 months, 1 year, and 2 years. RESULTS: A total of 47,903 cases were identified, of which 2,656 (5.5%) cases received IACI. The mean time from UKA to IACI was 355 days. The incidence of PJI in the IACI group was 2.7%, compared to 1.3% in the control group. The rate of PJI after IACI was significantly higher than the rate in the control group at 6 months, 1 year, and 2 years (all P < .05). The majority of PJI occurred within the first 6 months following IACI (75%). CONCLUSION: In this study, IACI in a UKA doubled the risk of PJI compared to patients who did not receive an injection. Surgeons should be aware of this increased risk to aid in their decision-making about injecting into a UKA. LEVEL OF EVIDENCE: III, retrospective comparative study.

Fluoroscopically Guided Acetabular Component Positioning: Does It Reduce the Risk of Malpositioning in Obese Patients?

BACKGROUND: Obesity has been described as an independent risk factor for acetabular component malpositioning. The purpose of this study was to determine if this could be overcome by use of fluoroscopic navigation in total hip arthroplasty (THA). METHODS: The first, postoperative, standing, anteroposterior pelvis radiographs from 1599 consecutive patients who underwent fluoroscopic-guided THAs via anterior approach during a six-year period were obtained. We retrospectively reviewed this prospectively collected data. Inclination and anteversion were measured as described by Barrack et al. Intraoperative target ranges for inclination and anteversion angles were 30°-50° and 5°-25°. Patients were divided into 3 cohorts by body mass index, nonobese (<30 kg/m2) obese (between 30 and 40 kg/m2) and morbidly obese (>40 kg/m2), looking for significant differences in acetabular component positioning. RESULTS: Of the 1599 patients, 1065 were nonobese, 506 obese, and 28 morbidly obese. Overall, average inclination was 37.7° and anteversion was 16.3°. Regarding inclination, 95.0% of cups were positioned in the safe zone, 95.7% for anteversion, and 91.2% for both inclination and anteversion. Analysis of each cohort individually revealed an average inclination of 37.5° in the nonobese, 37.9° in the obese, and 39.9° in the morbidly obese patients. For anteversion, each group's averages were 16.1°, 16.5°, and 16.0°, respectively. There was no significant relationship between a patient's body mass index and cup position for inclination (P = .867), anteversion (P = .673), or both inclination and anteversion (P = .624). CONCLUSION: Fluoroscopy is a useful tool for achieving a targeted acetabular component orientation in direct anterior THA, irrespective of patient BMI.

Revision total knee arthroplasty using a custom tantalum implant in a patient following multiple failed revisions.

The number of revision total knee arthroplasty procedures performed annually is increasing and, subsequently, so is the number of patients presenting following a failed revision. Rerevising a total knee arthroplasty after one or more failed revision procedures presents many challenges, including diminished bone stock for prosthetic fixation. "Off the shelf" implants may not offer the best alternative for reconstruction. We present the case of a 55-year-old patient who required a rerevision total knee arthroplasty following multiple failed revisions with severe femoral and tibia bone loss. We describe a novel technique we employed to improve component fixation within the compromised bone stock.

Alcohol Misuse is an Independent Risk Factor for Poorer Postoperative Outcomes Following Primary Total Hip and Total Knee Arthroplasty.

The influence of alcohol misuse on outcomes following primary total hip (THA) or knee (TKA) arthroplasty is poorly understood. Using the National Hospital Discharge Survey, a cohort representative of 8,372,232 patients (without cirrhosis) who underwent THA or TKA between 1990 and 2007 was identified and divided into two groups: (1) those who misused alcohol (n=50,861) and (2) those who did not (n=8,321,371). Differences in discharge status, comorbidities and perioperative complications were analyzed. Compared to patients with no diagnosis of alcohol misuse, alcohol misusers were nine times more likely to leave against medical advice and had longer hospital stays (P<0.001). Alcohol misuse was independently associated with higher odds of in hospital complications (OR: 1.334, range: 1.307-1.361), surgery related complications (OR: 1.293, range: 1.218-1.373) and general medical complications (OR: 1.300, range: 1.273-1.327).