Heterotopic Ossification after Traumatic Spinal Cord Injury: Use of NSAIDs for Prophylaxis
1Crew J, 1Pence B, 1McKenna S, 2Yurkiewicz S, 3Zakrasek E
1Santa Clara Valley Medical Center, San Jose, California, United states; 2Stanford University, Palo Alto, CA, United states; 3VA Palo Alto Health Care System, Palo Alto, California, United states
Objective: Heterotopic ossification (HO) is the pathologic deposition of lamellar bone in periarticular soft tissue and occurs in multiple clinical contexts, including spinal cord injury (SCI). Historical reports indicate the incidence of HO after SCI is somewhere between 16-78%. Two prior studies have demonstrated potential benefit from use of nonsteroidal anti-inflammatory drugs (NSAIDs) for preventing HO. Yet, recent survey data of SCI clinicians suggests there is very limited use of NSAIDs or other prophylactic measures against HO. We hypothesize that HO remains a common problem for those with motor complete SCI, and that NSAIDs lower risk for HO development.
Design/Methods: This is a retrospective chart review of SCI patients at a specialized SCI Rehabilitation Center where clinicians have adopted a strategy of considering NSAIDs for prophylaxis against HO. Patients with traumatic SCI admitted to the SCI Acute Rehabilitation Unit (ARU) over the past two years were identified by a diagnostic code search using Uniform Data Systems. Initial chart review was done to establish a more current incidence of HO, and compare incidence based on completeness of injury. Next, charts were screened to select for patients who received HO prophylaxis, and compared to those who did not. Fisher’s exact test was utilized to compare groups.
Results: A total of 36 recent patient records were reviewed, representing 29 males (81%) and 7 females (19%) with traumatic SCI. American Spinal Injury Association (ASIA) Impairment Scale (AIS) breakdown of the 36 patients demonstrated 12 with AIS A (33.3%), 6 with AIS B (16.5%), 6 with AIS C (16.5%), and 12 with AIS D (33.3%) at time of admission to the ARU. Ages ranged from 14 to 82 years. Initial random chart review of 30 patients discharged from ARU in 2016 revealed a total of 4 cases, an incidence of 13.3%. All 4 cases occurred in those with motor complete SCI, with 3 in AIS A and 1 in AIS B injuries. In comparing incidence of HO based on completeness of SCI, a significantly higher rate of HO was seen in those with motor complete vs. motor incomplete SCI (p=0.02). Of these 30 patients from 2016, 5 received NSAID prophylaxis against HO, 4 of whom were either AIS A or AIS B. Review of cases in 2017 to date revealed an additional 6 cases of AIS A or B SCI who received HO prophylaxis. Of the total 10 AIS A and B patients who received HO prophylaxis in 2016-17, 1 was diagnosed with HO within 4 days of starting NSAIDs whereas none of the remaining 9 were diagnosed with HO. In comparing this group with AIS A and B patients who did not receive prophylaxis (n=8), there was a nonsignificant trend towards NSAIDs reducing HO rates (p=0.08). No patients who received NSAIDs for HO prophylaxis were found to have GI bleeding or evidence of spinal hardware failure after NSAIDs were initiated.
Conclusion: Heterotopic ossification is significantly more common in those with motor complete traumatic SCI. The use of NSAIDs for HO prophylaxis amongst this SCI cohort is practical and potentially effective, but requires further evaluation in a larger prospective study with long term follow up.
You Must Be Logged In
This Reminders tab will display for your scheduled lectures 15 minutes before start time and for new messages waiting.