Troublesome Heterotopic Ossification after Central Nervous System Damage: A Survey of 570 Surgeries

François Genêt,Serge Poiraudeau,Philippe Denormandie,Didier Guillemot,Claire Jourdan,Thierry Judet,Alexis Schnitzler,Christine Lautridou,Mel Feany

doi:10.1371/journal.pone.0016632

François Genêt, Serge Poiraudeau + Show 7 more

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https://doi.org/10.1371/journal.pone.0016632

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Journal: PloS one	Publication Date: Jan 31, 2011
Citations: 90	License type: CC BY 4.0

Affiliation: Raymond Poincaré University Hospital, Hôpital Cochin

Abstract

BackgroundHeterotopic ossification (HO) is a frequent complication after central nervous system (CNS) damage but has seldom been studied. We aimed to investigate features of HO for the first time in a large sample and the rate of early recurrence of HO in terms of the time of surgery.Methodology/Principal FindingsWe retrospectively analyzed data from an anonymous prospective survey of patients undergoing surgery between May 1993 and November 2009 in our institution for troublesome HO related to acquired neurological disease. Demographic and HO characteristics and neurological etiologies were recorded. For 357 consecutive patients, we collected data on 539 first surgeries for HO (129 surgeries for multiple sites). During the follow-up, recurrences requiring another surgery appeared in 31 cases (5.8% [31/539]; 95% confidence interval [CI]: 3.8%–7.8%; 27 patients). Most HO requiring surgery occurred after traumatic brain injury (199 patients [55.7%]), then spinal cord injury (86 [24.0%]), stroke (42 [11.8%]) and cerebral anoxia (30 [8.6%]). The hip was the primary site of HO (328 [60.9%]), then the elbow (115 [21.3%]), knee (77 [14.3%]) and shoulder (19 [3.5%]). For all patients, 181 of the surgeries were performed within the first year after the CNS damage, without recurrence of HO. Recurrence was not associated with etiology (p = 0.46), sex (p = 1.00), age at CNS damage (p = 0.2), multisite localization (p = 0.34), or delay to surgery (p = 0.7).Conclusions/SignificanceIn patients with CNS damage, troublesome HO and recurrence occurs most frequently after traumatic brain injury and appears frequently in the hip and elbow. Early surgery for HO is not a factor of recurrence.

Highlights

Heterotopic ossification (HO) is defined as the formation within the soft tissues of abnormal, ectopic lamellar bone containing bone marrow [1,2,3,4]
HO is a frequent complication after central nervous system (CNS) damage
This survey of a large sample of patients with CNS damage revealed that most HO requiring surgery occurred after TBI, SCI, stroke and cerebral anoxia (CA)

Summary

Introduction

Heterotopic ossification (HO) is defined as the formation within the soft tissues of abnormal, ectopic lamellar bone containing bone marrow [1,2,3,4] It has 3 etiologies: 1) trauma (fractures, dislocations, post-surgery, burns), 2) genetic (fibrodysplasia ossificans progressiva (FOP), progressive osseous heteroplasia and Albright hereditary osteodystrophy), and 3) neurologic (mainly spinal cord injury [SCI] and traumatic brain injury [TBI]) [1,5,6]. CNS damage is believed to activate local factors such as bone morphogenic protein or systemic factors such as prostaglandin E2, or both [1,4,6] These factors could induce bone-forming mesenchymal cells to differentiate to osteoblasts in the periphery of the muscle and stimulate the formation of bone[1,4,12,17]. We aimed to investigate features of HO for the first time in a large sample and the rate of early recurrence of HO in terms of the time of surgery

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