Note 13 - Revenue and Geographic Information - Disaggregated Revenues (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Revenue	$ 147,794	$ 130,457	$ 114,610
Product [Member]
Revenue	$ 147,794	$ 130,457	$ 114,512
Percentage of revenue	100.00%	100.00%	100.00%
OA Pain Management [member]
Revenue	$ 89,503	$ 83,029	$ 103,466
Percentage of revenue	61.00%	64.00%	90.00%
Licensing, Milestone and Contract Revenue [Member]
Revenue	$ 0	$ 0	$ 98
Joint Preservation and Restoration [Member]
Revenue	$ 48,588	$ 39,368	$ 2,070
Percentage of revenue	33.00%	30.00%	2.00%
Non-Orthopedic [Member]
Revenue	$ 9,703	$ 8,060	$ 8,976
Percentage of revenue	6.00%	6.00%	8.00%