Risk factors associated with periprosthetic joint infection after total elbow arthroplasty.

BACKGROUND: For patients undergoing total elbow arthroplasty (TEA), the present study aimed to investigate: (i) what risk factors are associated with periprosthetic elbow infection; (ii) what is the incidence of infection after TEA; and (iii) what is the acuity with which these infections present? METHODS: The Statewide Planning and Research Cooperative System database was used to identify all patients who underwent TEA between 2003 and 2012 in New York State. Admissions for prosthetic joint infection (PJI) were identified using ICD-9 (International Classification of Diseases, Ninth Revision, Clinical Modification) diagnosis code 996.66. Multivariate analysis was used to determine risk factors that were independently prognostic for PJI. RESULTS: Significant risk factors for PJI included hypothyroidism [odds ratio (OR) = 2.04; p = 0.045], tobacco use disorder (OR = 3.39; p = 0.003) and rheumatoid arthritis (OR = 3.31; p < 0.001). Among the 1452 patients in the study period who underwent TEA, 3.7% (n = 54) were admitted postoperatively for PJI. There were 30 (56%) early infections, 17 (31%) delayed infections and seven (13%) late infections. CONCLUSIONS: Pre-operative optimization of thyroid function, smoking cessation and management of rheumatoid disease may be considered in surgical candidates for TEA. The results of the present study add prognostic data to the literature that may be helpful with patient selection and risk profile analysis. LEVEL OF EVIDENCE: Level III: prognostic study.

Protocol-Driven Revision for Stiffness After Total Knee Arthroplasty Improves Motion and Clinical Outcomes.

BACKGROUND: Stiffness after revision total knee arthroplasty (TKA) is a difficult problem without a well-defined treatment algorithm. The purpose of this study was to evaluate the results of revision TKA for stiffness within the context of differential component replacement. METHODS: Consecutive patients who underwent revision TKA were retrospectively identified and included those who received debridement and polyethylene liner exchange alone, revision of only one of the femoral or tibial fixed components, or revision of all components. Preoperative and postoperative range of motion and Knee Society score (KSS) were collected. RESULTS: Sixty-nine knees were included in the study group with a mean follow-up of 43 months (range, 12-205 months). The mean prerevision flexion contracture of 17° improved to 5° after surgical intervention (P < .001). Similarly, mean flexion and motion arc improved from 70° to 92° and from 53° to 87°, respectively (P < .001). Mean KSS knee scores improved from 42 to 70 and KSS function scores improved from 41 to 68 (P < .001). Mean arc of motion improved by 45° in patients who underwent complete component revision, 32° with component retention, and 29° with single component revision (P = .046). KSS knee scores improved by 34, 25, and 28 points in these respective groups (P = .049). KSS function scores improved by 33, 27, and 25 points (P = .077). CONCLUSION: Revision surgery with or without component revision can improve motion and function in patients with stiffness after TKA. Complete component revision may offer the largest improvements in these outcome measures in properly selected patients.

Intra-abdominal migration of a k-wire during revision total hip arthroplasty.

Revision total hip arthroplasty in the setting of severe acetabular bone loss is a challenging problem that is becoming more common. Kirschner wires are often used during acetabular revision for temporary fixation of trial components. We describe an intraoperative migration of a Kirschner wire through the acetabulum into the peritoneal cavity, requiring acute laparoscopic removal.

Economic evaluation of access to musculoskeletal care: the case of waiting for total knee arthroplasty.

BACKGROUND: The projected demand for total knee arthroplasty is staggering. At its root, the solution involves increasing supply or decreasing demand. Other developed nations have used rationing and wait times to distribute this service. However, economic impact and cost-effectiveness of waiting for TKA is unknown. METHODS: A Markov decision model was constructed for a cost-utility analysis of three treatment strategies for end-stage knee osteoarthritis: 1) TKA without delay, 2) a waiting period with no non-operative treatment and 3) a non-operative treatment bridge during that waiting period in a cohort of 60 year-old patients. Outcome probabilities and effectiveness were derived from the literature. Costs were estimated from the societal perspective with national average Medicare reimbursement. Effectiveness was expressed in quality-adjusted life years (QALYs) gained. Principal outcome measures were average incremental costs, effectiveness, and quality-adjusted life years; and net health benefits. RESULTS: In the base case, a 2-year wait-time both with and without a non-operative treatment bridge resulted in a lower number of average QALYs gained (11.57 (no bridge) and 11.95 (bridge) vs. 12.14 (no delay). The average cost was $1,660 higher for TKA without delay than wait-time with no bridge, but $1,810 less than wait-time with non-operative bridge. The incremental cost-effectiveness ratio comparing wait-time with no bridge to TKA without delay was $2,901/QALY. When comparing TKA without delay to waiting with non-operative bridge, TKA without delay produced greater utility at a lower cost to society. CONCLUSIONS: TKA without delay is the preferred cost-effective treatment strategy when compared to a waiting for TKA without non-operative bridge. TKA without delay is cost saving when a non-operative bridge is used during the waiting period. As it is unlikely that patients waiting for TKA would not receive non-operative treatment, TKA without delay may be an overall cost-saving health care delivery strategy. Policies aimed at increasing the supply of TKA should be considered as savings exist that could indirectly fund those strategies.

Custom intramedullary intercalating device for treatment of supracondylar fracture between constrained total knee arthroplasty and well-fixed total hip arthroplasty.

Management of periprosthetic fractures between ipsilateral total knee arthroplasty (TKA) and total hip arthroplasty (THA) is difficult, and is further complicated in the setting of poor femoral bone stock. We present a case of supracondylar fracture between THA and long-stemmed TKA femoral components in a patient with rheumatoid arthritis, deficient metaphyseal bone stock, and recurrent fractures. A long custom intramedullary intercalating component was devised to link the well-fixed existing THA stem to a revision distal femoral component. The resulting construct was stable and allowed for full weight-bearing ambulation, representing a useful treatment option in the management of periprosthetic fractures between revision TKA and well-fixed THA.

The withdrawn ASR™ THA and hip resurfacing systems: how have our patients fared over 1 to 6 years?

BACKGROUND: The Articular Surface Replacement™ (ASR™) metal-on-metal hip arthroplasty system (DePuy Orthopaedics, Inc, Warsaw, IN, USA) reportedly has a higher than anticipated early failure rate leading to a voluntary recall. This prompted us to evaluate all ASR™ components implanted at our center. QUESTIONS/PURPOSES: In all ASR™ components, we reported (1) revision rate, (2) blood metal ion levels, and (3) intraoperative findings for revisions related to adverse reaction to metal debris (ARMD). METHODS: We retrospectively reviewed all 172 patients (190 hips) who underwent THA (149 hips) or hip resurfacing (41 hips) with the ASR™ system. We determined failure rates. We obtained blood metal ion concentrations from 93 patients at last followup. We evaluated MRI studies and intraoperative histopathology. Minimum followup was 12 months (mean, 40 months; range, 12-74 months). RESULTS: At latest followup, we had revised 24 of 190 hips (13%): in 18 patients with THA and five patients with resurfacing. Mean time to revision was 45 months (range, 12-75 months). Mean blood concentrations were 13 µg/L (range, 0-150 µg/L) for cobalt and 6 µg/L (range, 0-87 µg/L) for chromium. Mean prerevision blood metal ion levels were higher in the revised group (cobalt: 48 µg/L; chromium: 18 µg/L) than in the nonrevised group (cobalt: 5 µg/L; chromium: 2 µg/L). ARMD was present in 14 of the 24 hips revised in this study. CONCLUSIONS: Surgeons must have a low threshold for concern for ARMD in patients with ASR™ systems. Blood metal ion levels and MRI can be used to evaluate patients with underperforming implants. Intraoperative histopathologic analysis and joint fluid cytology can help diagnose ARMD at the time of revision. LEVEL OF EVIDENCE: Level III, therapeutic study. See Instructions for Authors for a complete description of levels of evidence.

Creation of a femoral cortical window to facilitate total hip arthroplasty in patients with sickle cell hemoglobinopathies.

Patients with sickle cell hemoglobinopathies often have femoral head osteonecrosis with collapse, and can benefit greatly from total hip arthroplasty. However, numerous procedural challenges and perioperative complications make these cases difficult. More specifically, femoral canal preparation and proper component placement can be particularly challenging due to focal medullary sclerosis caused by repeated vascular insults to the bone. This study describes the creation of an anterior metaphyseal cortical bone window to aid in identification of the true femoral canal and to facilitate femoral component implantation.

Total knee arthroplasty in osteopetrosis using patient-specific instrumentation.

Osteopetrosis is an uncommon endocrine disease characterized by defective osteoclast resorption of bones. This causes a hard, sclerotic, and brittle bone throughout the skeleton. Fractures and unforgiving subchondral bone are common in this condition, both of which can lead to osteoarthritis. Total knee arthroplasty is often the treatment of choice but presents challenges due to the hard and sclerotic bone present throughout the metaphysis and diaphysis of the femur and the tibia. We present a case of knee osteoarthritis in a patient with osteopetrosis who underwent total knee arthroplasty using patient-specific instrumentation. This technique eliminates intramedullary alignment and minimizes drilling, reaming, and saw passes, making it attractive in the setting of diseases such as osteopetrosis to decrease operative time and potential complications.

Role of diabetes type in perioperative outcomes after hip and knee arthroplasty in the United States.

The objective of this study was to determine whether the type of diabetes mellitus (DM) affected the incidence of immediate perioperative complications following joint replacement. From 1988 to 2003, the Nationwide Inpatient Sample recognized 65,769 patients with DM who underwent total hip and knee arthroplasty in the United States. Bivariate and multivariate analyses compared patients with type 1 (n = 8728) and type 2 (n = 57,041) DM regarding common perioperative complications, mortality, and hospital course alterations. Type 1 DM patients had increased length of stays and inflation-adjusted costs after surgery (p < .001). Type 1 patients also had significant increases in the incidence of myocardial infarction, pneumonia, urinary tract infection, postoperative hemorrhage, wound infection, and death (p < .02). Perhaps because of the differences in the duration of disease and their underlying pathologies, patients with type 1 diabetes carry more significant overall perioperative risks and require more health care resources compared with patients with type 2 diabetes following hip and knee arthroplasty.