RESUMO
Objective: Osteoarthritis of the knee (knee OA) is a serious joint disease leading to pain and reduced quality of life. Pharmacological treatments include anti-inflammatories, analgesics, intraarticular hyaluronic acid, and intraarticular corticosteroids while for severe knee OA, knee replacement is an option. This study examined the incidence, prevalence, patient characteristics, and uptake of medical and surgical treatments in knee OA patients in Germany. Design: A non-interventional, retrospective health claims data analysis with anonymized data from the InGef database was performed. Patients ≥18 years were analyzed cross-sectionally for each year 2015-2020. Newly diagnosed patients in 2015 were also longitudinally analyzed until end of 2020. Results: Annual knee OA prevalence increased from 7.07 â% in 2015 to 7.39 â% in 2020. Annual incidence proportions ranged from 1.71 â% in 2015 to 1.46 â% in 2020. Knee replacement was the most common surgery, with rising patient numbers (e.g., 7918 patients in 2015 and 8975 patients in 2019). Approximately 62 â% of patients newly diagnosed in 2015 received prescription pharmacological pain treatment during follow-up. Most (96.95 â%) received non-opioid analgesics, followed by weak opioids (8.14 â%) and strong opioids (3.00 â%) as first-line treatment (combinations possible). Knee surgery was performed in 16.6 â% of patients during follow-up. Median time from first diagnosis until surgery was 346 days for any knee surgery and 564 days for knee replacement. Conclusions: The number of patients with knee OA in Germany is steadily rising, along with an increasing number of surgical interventions, especially knee replacement. Time until first surgery and knee replacement is relatively short, even for newly diagnosed patients.
RESUMO
Intra-articular injection of mono-iodoacetate (MIA) in the rat knee joint induces a histopathology with similarities to osteoarthritis (OA). Typically, a synovitis (days 1-3) is observed followed by thinning of articular cartilage and subsequent lesion of subchondral bone at days 8-14 onwards. Behaviourally, weight-bearing asymmetry is observed, which is sensitive to anti-inflammatory pharmacology at early but not later (days 14+) time points. As subchondral bone is densely innervated, an intriguing possibility is that focal bone pathology may cause neuropathy in this model. In male Wistar rats, activating transcription factor (ATF)-3-immunofluorescence was used as a marker of nerve injury in lumber (L)4 and L5 dorsal root ganglia of the ipsilateral knee. Significantly increased ATF-3-immunoreactivity following MIA treatment was measured in L5 on days 8 and 14 (P<0.05, Kruskal-Wallis and Mann-Whitney U-test), compared to saline controls. Furthermore, in an additional study animals were orally dosed vehicle (5 ml/kg), naproxen (0.3-10 mg/kg), celecoxib (1-10 mg/kg), amitriptyline (3-30 mg/kg) and gabapentin (10-100mg/kg) and evaluated for weight-bearing asymmetry on days 14, 21 and 28 post-MIA. Significant resolution of weight-bearing was observed at high and intermediate doses of amitriptyline and gabapentin at all time points (P<0.05, ANOVA, post-hoc Bonferroni's, vs pre-dose measurements). Transient and weak effects were observed with naproxen (10mg/kg) on days 14 and 28, whereas celecoxib showed no significant effects. Collectively, these data suggest that this putative model of OA is associated with an early phase neuropathy in the L5 innervation territory of the knee.