The Impact of Preoperative Hip Heterotopic Ossification Extent on Recurrence in Patients with Head and Spinal Cord Injury: A Case Control Study

Abstract

BackgroundThe preoperative Heterotopic Ossification (HO) extent is usually one of the main used criteria to predict the recurrence before excision. Brooker et al built a radiologic scale to assess this pre operative extent around the hip. The aim of this study is to investigate the relationship between the recurrence risk after hip HO excision in Traumatic Brain Injury (TBI) and Spinal Cord Injury (SCI) patients and the preoperative extent of HO.Methodology/Principal FindingsA case control study including TBI or SCI patients following surgery for troublesome hip HO with (case, n = 19) or without (control, n = 76) recurrence. Matching criteria were: sex, pathology (SCI or TBI) and age at the time of surgery (+/−4.5 years). For each etiology (TBI and SCI), the residual cognitive and functional status (Garland classification), the preoperative extent (Brooker status), the modified radiological and functional status (GCG-BD classification), HO localization, side, mean age at the CNS damage, mean delay for the first HO surgery, and for the case series, the mean operative delay for recurrence after the first surgical intervention were noted.Conclusions/SignificanceThe median delay for first HO surgery was 38.6 months (range 4.5 to 414.5;) for the case subgroup and 17.6 months (range 5.7 to 339.6) for the control group. No significant link was found between recurrence and operative delay (p = 0.51); the location around the joint (0.07); the Brooker (p = 0.52) or GCG-BD status (p = 0.79). Including all the matching factors, no significant relationship was found between the recurrence HO risk and the preoperative extent of troublesome hip HO using Brooker status (OR = 1.56(95% CI: 0.47–5.19)) or GCG-BD status (OR class 3 versus 2 = 0.67(95% CI: 0.11–4.24) and OR class 4 versus 2 = 0.79(95%CI: 0.09–6.91)). Until the pathophysiology of HO development is understood, it will be difficult to create tools which can predict HO recurrence.

Identifying the Cellular Mechanisms Leading to Heterotopic Ossification

“…Both hereditary and acquired HO are debilitating conditions that can lead to the atrophy of skin and soft tissue breakdown throughout the residual limb, severe pain, nerve entrapment and impaired joint movement. Current treatments are invasive (surgical removal) or non-specific (radiation therapy or non-steroidal anti-inflammatory drugs), with the likelihood of HO recurrence potentially reaching levels of 25% [6,8]. Therefore, the need to understand the complex pathological mechanisms underlying HO is of great importance if effective therapies are to be devised.…”

Novel mouse model of spinal cord injury-induced heterotopic ossification

“…Unfortunately, these treatment options have been unsuccessful in preventing or curing HO. Surgical excision has recurrence rates as high as 25 percent, requiring further surgery [3,[13][14]. Likewise, these treatments may cause additional morbidity and mortality to patients.…”

Beliefs relating to recurrence of heterotopic ossification following excision in patients with spinal cord injury: a review

“…We carried out a case-control study using the BANKHO database. 28 No significant relationship was found between recurrence and the location around the joint or the Brooker status, even when all the matching factors were included in the analysis.…”

“…Recurrence was evaluated in the total sample (539 surgeries), 5 as well as in sub-groups comprising traumatic brain injury and SCI patients (95 interventions). 28 Does the extent of the HO affect the risk of recurrence of troublesome HO after CNS lesion? Historical approach.…”