Effect of Posterior Osteophytes on Total Knee Arthroplasty Coronal Soft Tissue Balance: Do They Matter?

BACKGROUND: Achieving coronal plane balance in total knee arthroplasty (TKA) is of paramount importance. There is concern that obtaining balancing before removal of posterior osteophytes may lead to asymmetrical extension balance once removed. We hypothesized that there is a particular posterior osteophyte size and location that does not result in significant change in coronal gap balancing. METHODS: In this study of 245 robotic arm-assisted TKAs, the size and location of posterior osteophytes were obtained from preoperative computer tomography scans. Gap measurements at 10°-25° and 90° flexion after removal of medial and lateral osteophytes, before and after posterior osteophyte removal and bone resection were compared with respect to the size and location of posterior osteophytes. RESULTS: The largest size posterior osteophytes measured >10 mm in 8.2% of cases, 5-10 mm in 34.7%, <5 mm in 23.7%, and 23.7% had no osteophytes. The mean osteophyte size was 5.7 mm. The cohorts with and without posterior osteophytes were both found to have significant but similar changes in all gaps after osteophyte removal and bone resection (mean 0.8-1.4 mm, P < .0001 and mean 0.7-1.7 mm, P < .0001, respectively). Osteophyte size and location had no significant effect on the change in postresection gaps. This included osteophytes greater than 10 mm, but their incidence was small. CONCLUSION: There is a small significant change in gaps between initial assessment and subsequent TKA bone resections, with or without posterior osteophytes. Our study found that where the surgeon thoroughly removes the medial and lateral osteophytes on initial exposure, posterior osteophytes <10 mm can be ignored during initial knee coronal balancing.

Clostridium difficile colitis in patients undergoing lower-extremity arthroplasty: rare infection with major impact.

BACKGROUND: The prevalence of Clostridium difficile colitis is reportedly increasing in surgical patients and can negatively impact their outcome. However, as yet there are no clear estimates of the C difficile infection colitis rate and its consequences among patients undergoing total joint arthroplasty (TJA). QUESTIONS/PURPOSES: We asked: (1) What is the rate of C difficile colitis in TJA patients? (2) What are the risk factors of C difficile colitis in these patients? And (3) what is the effect of C difficile colitis on length of stay, in-hospital mortality, and estimated total charges? METHODS: Using ICD-9-CM diagnosis and procedure codes, we queried the Nationwide Inpatient Sample database for patients undergoing TJA for the years 2002 to 2010. Demographic data, comorbidities, occurrence of C difficile colitis, length of hospital stay, mortality, and hospital charges were extracted. Logistic regression was performed to identify predictors of C difficile colitis and its impact on in-hospital mortality. RESULTS: The incidence of C difficile remained less than 0.6% during the study period. Revision TJAs (odds ratio=6.9 and 4.4 for hip and knee, respectively) and number of comorbidities (odds ratio=1.5) increased risk of C difficile colitis. C difficile increased length of hospital stay by a week, hospital charges by USD 40,000, and in-hospital mortality to 4.66% from 0.24%. CONCLUSIONS: Using lower and fewer doses of antibiotics in revision TJAs and among patients with many comorbidities may diminish risk of C difficile colitis and its consequent mortality. LEVEL OF EVIDENCE: Level II, prognostic study. See Instructions for Authors for a complete description of levels of evidence.

Complex Total Hip Arthroplasty in a Patient with Klippel-Trénaunay Syndrome: A Case Report.

CASE: Klippel-Trénaunay syndrome (KTS) carries manifestations including skeletal dysplasia and prominent vascular malformations. This report details a case of hip dysplasia in the setting of KTS treated with total hip arthroplasty (THA) requiring preoperative embolization, intraoperative angiography for placement of an iliac artery occlusive balloon, and modular hip arthroplasty components for femoral and acetabular dysplasia. Perioperatively, the patient rehabilitated well and was walking painlessly and unassisted at 3 and 12 months postoperatively. CONCLUSION: Successful THA for dysplasia and degenerative changes associated with KTS is possible but requires a complex multidisciplinary perioperative approach.

Early adverse results with bicompartmental knee arthroplasty: a prospective cohort comparison to total knee arthroplasty.

This prospective cohort study compares functional outcomes of bicompartmental knee arthroplasty (BKA) and total knee arthroplasty (TKA) in patients with osteoarthritis (OA) of the patellofemoral and medial compartments. Eligibility criteria included bicompartmental OA with less than grade 2 OA in the lateral compartment and intact cruciate ligaments. Fifty-six patients met eligibility criteria (21 BKA, 33 TKA). Enrolled participants completed Short-Form 12 and Western Ontario and McMaster Universities Osteoarthritis Index assessments at baseline and postoperatively at 3 months, 1 year, and 2 years. In the early postoperative period, the BKA cohort had significantly less pain (P = .020) and better physical function (P = .015). These trends did not continue past 3 months. When adjusting for age, sex, body mass index, and preoperative status, only 3-month Western Ontario and McMaster Universities Osteoarthritis Index stiffness scores significantly differed between cohorts (P = .048). Despite less early stiffness in the BKA cohort, a significantly higher BKA complication rate (P = .045) has led us to recommend TKA for patients with this pattern of OA.

Predicting short-term outcome of primary total hip arthroplasty:a prospective multivariate regression analysis of 12 independent factors.

The purpose of this study was to investigate factors affecting the short-term outcome of primary total hip arthroplasty (THA) and develop a multivariate regression equation to predict the short-term outcome of primary THA. Prospectively collected data for 101 primary THAs performed at a single institution were used in this study. Twelve independent variables were analyzed via correlation and multivariate regression analyses. Correlation analyses showed that three variables significantly influenced Western Ontario and McMaster Universities Osteoarthritis (WOMAC) physical function (PF) score at minimum follow-up of 1 year: preoperative WOMAC PF score (P < .0001), sex (GN, P = .0159), and the presence of preoperative comorbidities (CMB, P = .0246). Multivariate regression analysis yielded the following equation: Outcome = PF0.45 - GN9 + CMB8 + 62, which can be used to predict the general short-term outcome of primary THA.

The effect of fixation technique on the stiffness of comminuted Vancouver B1 periprosthetic femur fractures.

The purpose of this study was to evaluate the stiffness of 3 different constructs for the fixation of comminuted Vancouver B1 periprosthetic femoral shaft fractures: a single lateral locking plate, a single lateral locking plate plus an anterior strut allograft, and a lateral locking plate plus an anterior locking plate. The axial stiffness, lateral bending stiffness, and torsional stiffness of 10 synthetic periprosthetic femur fracture models were tested. Differences in stiffness between constructs were determined with a 1-way repeated-measures analysis of variance. Fixation technique was found to have a significant effect for all loading modalities (P < .0001). A lateral locked plate plus an anterior locked plate was significantly stiffer than the allograft that in turn was significantly stiffer than the single plate (P < .0001).

Tip-apex distance of intramedullary devices as a predictor of cut-out failure in the treatment of peritrochanteric elderly hip fractures.

A tip-apex distance (TAD) of greater than 25 mm has been shown to be an accurate predictor of lag screw cut-out when sliding hip screws (SHS) are used to treat peritrochanteric (PT) hip fractures. The purpose of this study was to determine which factors, including TAD, correlated with successful clinical outcomes of PT hip fractures surgically treated with intramedullary (IM) devices. A total of 192 patients were included in this retrospective study. The TAD values of this cohort were radiographically analysed at a mean follow-up of 13 months. This was correlated with limited functional status and the rate of revision for implant failure or inability to achieve fracture union. Only 82 patients had adequate follow-up to fracture union or definitive failure. There were 46 intertrochanteric (IT) hip fractures and 36 subtrochanteric (ST) fractures. Overall, seven patients (8.5%) went on to experience lag screw cut-out. The average TAD of the patients who did not cut-out was 18 mm, compared to 38 mm for those who did (p = 0.012). All patients who cut-out had IT fractures (p = 0.017). The percentage of cut-outs correlated directly to both the severity of IT fractures and the TAD. Using a cutoff of 25 mm there was a statistically significant difference in the incidence of lag screw cut-out (p < 0.001). As in sliding hip screws, surgeons should strive for a TAD less than 25 mm when using IM devices in the treatment of PT hip fractures to help avoid lag screw cut-out.

Appropriate Use Criteria for the Nonarthroplasty Treatment of Knee Osteoarthritis in Veterans.

While patients without knee instability use more nonarthroplasty treatments over a longer period prior to total knee arthroplasty, patients with less severe knee osteoarthritis are at risk of receiving interventions judged to be rarely appropriate.

No Difference in Conventional Polyethylene Wear Between Yttria-stabilized Zirconia and Cobalt-chromium-molybdenum Femoral Heads at 10 Years.

BACKGROUND: Concerns have arisen regarding deterioration of wear properties of yttria-stabilized zirconia (YSZ) femoral head on conventional polyethylene (PE) bearings due to YSZ phase transformation. QUESTIONS/PURPOSES: The purpose of this study was to determine if there is a difference in long-term PE wear properties between YSZ and cobalt-chromium-molybdenum (Co-Cr-Mo) femoral heads. METHODS: Ten-year radiographic wear assessment was performed on a cohort of patients enrolled in a prospective randomized clinical trial comparing total hip arthroplasty with YSZ or Co-Cr-Mo femoral heads on conventional, non-cross-linked PE. RESULTS: PE linear wear, annualized wear, and steady-state wear rates remained low and similar between groups. No cases of osteolysis were observed. CONCLUSIONS: Measured conventional PE wear was similar between YSZ and Co-Cr-Mo femoral heads with the steady-state wear rates for both remaining below the generally accepted threshold at which osteolysis typically occurs. Whether clinically relevant phase transformation with YSZ femoral heads occurs is uncertain; however, the use of YSZ femoral heads in this study was not associated with increased PE wear, osteolysis, or deterioration of wear properties.

Premature Consolidation with Resultant Implant Failure Using PRECICE Femoral Nail Lengthening: A Case Report.

CASE: Posttraumatic limb-length discrepancies secondary to femoral malunion can be treated with a variety of external or internal lengthening systems. The PRECICE nail is an intramedullary device featuring an external remote control to activate a magnetically driven internal distraction mechanism. While this intramedullary system avoids the soft-tissue complications common to external lengthening, it has unique mechanisms of failure that are difficult to diagnose and that require a systematic approach. CONCLUSION: In this case report, we describe a failure to lengthen with the PRECICE femoral nail and the subsequent steps taken to determine the root cause. We believe that this failure represents the first reported case of malfunction of the PRECICE femoral nail distraction mechanism since its 2013 redesign.

Periprosthetic joint infection in patients with inflammatory joint disease: a review of risk factors and current approaches to diagnosis and management.

BACKGROUND: Prevention, early identification, and effective management of periprosthetic joint infection (PJI) in patients with inflammatory joint disease (IJD) present unique challenges for physicians. Discontinuing disease-modifying anti-rheumatoid drugs (DMARDs) perioperatively may reduce immunosuppression and infection risk at the expense of increasing disease flares. Interpreting traditional diagnostic markers of PJI can be difficult due to disease-related inflammation. PURPOSES: This review is designed to answer how to (1) manage immunosuppressive/DMARD therapy perioperatively, (2) diagnose PJI in patients with IJD, and (3) treat PJI in this population. METHODS: The PubMed database was searched for relevant articles with subsequent review by independent authors. RESULTS: While there is evidence to support the use of methotrexate perioperatively in RA patients, it remains unclear whether using anti-tumor necrosis factor medications perioperatively increases the risk of surgical site infections. Serum erythrocyte sedimentation rate and C-reactive protein can be useful for diagnosis of PJI in this population, but only as part of comprehensive workup that ultimately relies upon sampling of joint fluid. Management of PJI depends on several clinical factors including duration of infection and the likelihood of biofilm presence, the infecting organism, sensitivity to antibiotic therapy, and host immune status. The evidence suggests that two-stage revision or resection arthroplasty is more likely to eradicate infection, particularly when MRSA is the pathogen. CONCLUSION: Immunosuppression and baseline inflammatory changes in the IJD population can complicate the prevention, diagnosis, and treatment of PJI. Understanding the increase in risk associated with IJD and its treatment is essential for proper management when patients undergo lower extremity arthroplasty.

Hip resurfacing is less painful at 24 hours than hip replacement.

This article quantifies pain differences in the immediate postoperative period between patients undergoing total hip arthroplasty (THA) and metal-on-metal hip resurfacing (MoMHR). Patients less than 65 years old indicated for either a primary MoMHR or THA were screened for consent. A total of 51 patients completed the study. Controlling for confounding factors, patients having MoMHR experienced significantly less pain at 24 hours than patients having THA. The MoMHR cohort experienced a significantly shorter length of stay than the THA cohort. MoMHR shows a significantly lower pain level at 24 hours than THA and a significantly earlier discharge.

Factors affecting response rates to mailed preoperative surveys among arthroplasty patients.

AIM: To identify factors that affect patient response rates to preoperative functional surveys in hip and knee arthroplasty patients. METHODS: From May 2008 to March 2009, 247 patients were scheduled more than 4 wk in advance for hip or knee arthroplasty by one of two participating surgeons at our center. A personalized questionnaire comprised of the Short Form 12 (SF-12) and Western Ontario and McMaster Universities (WOMAC) Index was mailed to patients at random time points ranging from 7 to 101 d prior to surgery. Nine independent factors were documented prospectively, including age, gender, ethnicity, marital status, type of surgery, surgeon, days prior to surgery (DPS) of survey mailing, WOMAC score and SF-12 score. The date of the completed survey receipt was also documented. For non-responders, the surveys were completed with the research team at the hospital upon admission. Multivariate regression and χ(2) analysis were performed with Statistical Analysis Software software. RESULTS: DPS was the only factor that affected patient response. Mailing surveys 26 d to 31 d prior to surgery dates led to a peak response rate of 80% that was significantly higher (P < 0.023) than response rates for patients who were mailed their surveys ≤ 16 d (62.5%), 17 d to 25 d (70%) or ≥ 32 d prior to surgery (55%). No other factors, including preoperative WOMAC and SF-12 scores, significantly influenced response behavior. CONCLUSION: The DPS was independently the most significant predictor of response rates for pre-operative functional data among patients scheduled for hip and knee arthroplasty.