Stock-Benefit Plans and Equity Transactions (Tables)

6 Months Ended

Jun. 30, 2021

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Summary of Total Stock Based Compensation

Stock-Based Compensation

Total stock-based compensation for the periods presented were as follows (in thousands):

	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2021		2020		2021		2020
Cost of revenues	$	235	$	128	$	330	$	235
Research and development		664		563		1,162		954
Sales, general and administrative		10,597		3,884		14,478		6,954
Total	$	11,496	$	4,575	$	15,970	$	8,143

Summary of Common Stock Reserved for Future Issuance

As of June 30, 2021, the Company’s shares of common stock reserved for future issuance were as follows (in thousands):

Stock options outstanding	3,616
Unvested restricted stock award	8,678
Employee stock purchase plan	662
Series A convertible preferred stock	29
Warrants outstanding	20,525
Authorized for future grant under the Distributor and    Development Services plans	952
Authorized for future grant under the Management    Objective Strategic Incentive Plan	345
Authorized for future grant under the Company equity    plans	4,496
Total	39,303

Summary of All Outstanding Warrants for Common Stock

A summary of all outstanding warrants for common stock as of June 30, 2021 were as follows:

	Number of Warrants		Strike Price		Expiration
2017 PIPE Warrants		2,587,000	$	2.00	June 2022
2018 PIPE Warrants		8,538,569	$	3.50	May 2023
SafeOp Surgical Merger Warrants		1,194,943	$	3.50	May 2023
2018 Squadron Medical Warrants		845,000	$	3.15	May 2027
2019 Squadron Medical Warrants		4,838,710	$	2.17	May 2027
2020 Squadron Medical Warrants		1,075,820	$	4.88	May 2027
Executive Warrants		1,327,434	$	5.00	December 2022
Other(1)		117,812	$	2.87	Various through May 2023
Total		20,525,288

(1) Weighted-average strike price.