Hyaluronic Acid Injections in Medicare Knee Osteoarthritis Patients Are Associated With Longer Time to Knee Arthroplasty.

BACKGROUND: Few nonoperative treatment options for knee osteoarthritis (OA) are available, but there is ongoing debate about the effectiveness of intra-articular (IA) hyaluronic acid (HA) injections. We investigated whether the formulation of IA HA, or its combined use with IA corticosteroid (CS), may be contributing to some of the reported variation in clinical outcomes. METHODS: The 5% Part B Medicare data (2005-2012) were used to identify knee OA patients who underwent knee arthroplasty (KA). The time from diagnosis of OA to KA was compared between patients with (HA) and without (no HA) IA HA use, using quantile regression with propensity score adjustment. These were further stratified by type of IA HA. Patient factors associated with time to KA were also assessed using Cox regression. RESULTS: The "HA" cohort was associated with a longer time to KA of 8.7 months (95% confidence interval: 8.3-9.1 months; P < .001) compared with the "no HA" cohort, with extended time to KA in the bioengineered Euflexxa IA HA cohort. Patient factors associated with longer time to KA included women, younger patients, minority patients, patients with fewer comorbidities, and IA CS injection use. Patients with both IA HA and IA CS had an additional 6.3 months (95% confidence interval: 5.5-7.0 months; P < .001) to KA over those with only IA HA. CONCLUSION: In a large cohort of elderly patients undergoing KA, there was a significant longer time from diagnosis of OA to KA in those receiving IA HA. It is unclear if the extended time may lead to less KA utilization.

Cost-effectiveness analysis of intra-articular injections of a high molecular weight bioengineered hyaluronic acid for the treatment of osteoarthritis knee pain.

OBJECTIVE: To determine the cost-effectiveness of bioengineered hyaluronic acid (BioHA, 1% sodium hyaluronate) intra-articular injections in treating osteoarthritis knee pain in poor responders to conventional care (CC) including non-steroidal anti-inflammatory drugs (NSAIDs) and analgesics. METHODS: Two decision analytic models compared BioHA treatment with either continuation of patient's baseline CC with no assumption of disease progression (Model 1), or CC including escalating care costs due to disease progression (NSAIDs and analgesics, corticosteroid injections, and surgery; Model 2). Analyses were based on patients who received two courses of 3-weekly intra-articular BioHA (26-week FLEXX Trial + 26-week Extension Study). BioHA group costs included fees for physician assessment and injection regimen, plus half of CC costs. Cost-effectiveness ratios were expressed as averages and incremental costs per QALY. One-way sensitivity analyses used the 95% confidence interval (CI) of QALYs gained in BioHA-treated patients, and ±20% of BioHA treatment and CC costs. Probabilistic sensitivity analyses were performed for Model 2. RESULTS: For 214 BioHA patients, the average utility gain was 0.163 QALYs (95% CI = -0.162 to 0.488) over 52 weeks. Model 1 treatment costs were $3469 and $4562 for the BioHA and CC groups, respectively; sensitivity analyses showed BioHA to be the dominant treatment strategy, except when at the lower end of the 95% CI. Model 2 annual treatment costs per QALY gained were $1446 and $516 for the BioHA and CC groups, respectively. Using CC as baseline strategy, the incremental cost-effectiveness ratio (ICER) of BioHA was $38,741/QALY gained, and was sensitive to response rates in either the BioHA or CC groups. CONCLUSION: BioHA is less costly and more effective than CC with NSAIDs and analgesics, and is the dominant treatment strategy. Compared with escalating CC, the $38,741/QALY ICER of BioHA remains within the $50,000 per QALY willingness-to-pay threshold to adopt a new technology.

Quantitative and qualitative assessment of closed fracture healing using computed tomography and conventional radiography.

RATIONALE AND OBJECTIVES: Development of new agents to induce fracture healing requires more sensitive methods to detect early changes in fracture repair. The aims of this study were to determine quantitative and qualitative features of fracture healing using volumetric computed tomography (CT) and to compare them with conventional radiography during the weeks following uncomplicated fractures of the appendicular skeleton. MATERIALS AND METHODS: 39 otherwise healthy men and women with acute, closed fractures of the distal radius, tibial and/or fibular malleoli, or tibial shaft, were enrolled and underwent CT and X-ray imaging at 1, 2, 4, 8, 12, and 16 (tibial shaft only) weeks post fracture. Qualitative assessment included fracture line/margins, fracture gap, external callus appearance, callus-to-cortex ratio, bridging, and radiologic union. Quantitative assessment of CT density changes (Hounsfield units [HU]) in the fracture gap was performed in a subset of 8 fracture patients using MEDx multimodality image analysis software (Sterling,VA). The analysis was performed by drawing free form regions of interest (ROI) covering the fracture gap on baseline (week 1) images and by automated registration of the follow-up images to the baseline co-ordinate system. RESULTS: The mean time to achieve radiologic union on CT was slightly shorter than on X-rays for radial and tibial shaft fractures (7.3 vs. 8.0 weeks, P = .1). Blurring of the fracture margins and reactive sclerosis were the earliest signs of healing in both modalities. External callus formation was evident in 11 cases and was detected earlier with CT technique. Overall, CT images allowed for more complete and detailed visualization of healing compared with conventional X-rays, which were limited by cast and fixation hardware superimposition, especially in subjects with malleolar and distal radial fractures. Quantitative evaluation showed good intraobserver and interobserver reproducibility and a statistically significant correlation to qualitative changes. CONCLUSION: Our methods of fracture healing assessment are reliable tools that are able to detect early changes in normal bone healing and may serve as useful additions to subjective image analysis in monitoring fracture healing in clinical trials. CT shows some advantages over conventional X-rays in evaluation of early fracture healing.