California hospitals got paid twice, to the tune of $67.5 million in 2010, for spinal surgeries performed on workers' compensation patients. That's according to a new study from the California Workers' Compensation Institute. These unusual duplicate payments, which only apply to spinal surgeries, stem from the way that the state workers' compensation program reimburses health care providers for care. Typically, hospitals are paid 120 percent for medical services given to injured workers, compared with what they receive for Medicare patients. The report estimates that the duplicate payments for spinal instruments add $20,000 to the cost of each procedure. The analysis was based on 3,350 surgeries.