Treatment of heterotopic ossification of the elbow following burn injury: recommendations for surgical excision and perioperative prophylaxis using radiation therapy

Bony encasement of the ulnar nerve secondary to heterotopic ossification of the elbow: an evaluation of long-term outcomes

BACKGROUND

Ulnar neuropathy at the elbow caused by heterotopic ossification (HO) is a rare condition. This retrospective study aims to report on 32 consecutive cases of ulnar nerve encasement caused by elbow HO and evaluate long-term outcomes of operative management and a standardized postoperative rehabilitation regimen.

METHODS

A retrospective case series was conducted on 32 elbows (27 patients) that underwent operative management of bony ulnar nerve encasement. All procedures were performed in the inpatient setting at an Academic Level 1 Trauma Center from September 1999 to July 2021 by one of 3 fellowship-trained shoulder and elbow. Postoperatively, all patients received formal physical therapy, HO prophylaxis (30 received indomethacin, 2 received radiation), and a structured continuous passive motion machine regimen. Patient demographics, age, gender, type of injury, history of tobacco use, and medical comorbidities were obtained to include in the analysis. Long-term follow-up examinations were performed to evaluate elbow flexion-extension arc of motion, Mayo Elbow Performance Score, and visual analog scale pain scores.

RESULTS

Thirty-two elbows with complete bony ulnar nerve encasement secondary to HO were identified (14 from burns, 15 from trauma, 3 closed head injuries). Following surgery, the mean flexion-extension arc of motion improved significantly, increasing from 21° to 100° at long-term follow-up (average 8.7 years, range 2-17 years), with statistically significant improvements in preoperative vs. long-term postoperative elbow extension (P < .001), flexion (P < .001), and total arc of motion (P < .001). There was a statistically significant improvement in pre- vs. postprocedure ulnar nerve function, as demonstrated by a decrease in average McGowan grade (1.2-0.7; P = .002). Additionally, 63% of patients with preoperative ulnar neuropathy symptoms (20/32) had either complete resolution or subjective improvement after surgery. The mean time from injury to surgery was 518 days (range 65-943 days). Age, gender, time to surgery, and medical comorbidities were not associated with outcomes. The complication rate was 9% (3/32). Patients had an average flexion-extension arc of motion of 97° and average Mayo Elbow Performance Score of 80 ("good") at long-term follow-up.

CONCLUSIONS

The combination of operative management, postoperative HO prophylaxis, and a regimented rehabilitation program has proven to be a durable solution for treating and ensuring good long-term functional outcomes for patients with elbow HO and bony ulnar nerve encasement. This treatment approach leads to superior range of motion, improved or resolved ulnar neuropathy, and good to excellent long-term functional outcomes.

Heterotopic Ossification in Burn Patients

ABSTRACT

Heterotopic ossification (HO) is a known complication of burns. The incidence of this complication is low. The etiology is unclear, but experiment conducted about HO can be significant. Currently, there are still no targeted, effective preventive and therapeutic measures against it. In this study, the relevant literature is summarized to demonstrate the potential pathogenic mechanisms, diagnosis, prophylaxis, and treatment measures of HO in burn patients. Early diagnosis and treatment can be effective in improving the prognosis of patients.

Heterotopic Ossification: Clinical Features, Basic Researches, and Mechanical Stimulations

Heterotopic ossification (HO) is defined as the occurrence of extraskeletal bone in soft tissue. Although this pathological osteogenesis process involves the participation of osteoblasts and osteoclasts during the formation of bone structures, it differs from normal physiological osteogenesis in many features. In this article, the primary characteristics of heterotopic ossification are reviewed from both clinical and basic research perspectives, with a special highlight on the influence of mechanics on heterotopic ossification, which serves an important role in the prophylaxis and treatment of HO.

Heterotopic Ossification of the Inferior Vena Cava Wall: A Case Report and Literature Review

Masses of the inferior vena cava (IVC) are very diverse, most of which are thrombus and tumor thrombus, whereas heterotopic ossification of IVC has never been reported. Heterotopic ossification (HO) is the formation of mature lamellar bone outside normal bones and in soft tissues. Some researchers believe that HO is a manifestation of vascular calcification. Here we present a case of HO of the inferior vena cava (IVC) wall. A 68 year old female patient complaining hypertension and palpitation and diagnosed with a retroperitoneal mass was found to have a primary mass of the inferior vena cava wall during surgery. Histopathological examination after surgical resection revealed that the mass was mainly composed of mature bone tissues and hematopoietic tissues of bone marrow, there was no recurrence and the patient was symptom-free 15 months after the surgery. HO of the inferior vena cava wall is very rare, with large volume it can affect the circulation, and this case remind us that it can be cured by surgical resection.

Surgical excision of heterotopic ossification associated with anti-N-methyl-d-aspartate receptor encephalitis: A case report

INTRODUCTION AND IMPORTANCE

Heterotopic ossification (HO) associated with Anti-N-methyl-d-aspartate (anti-NMDA) receptor encephalitis is rare and the treatment strategy is unclear.

CASE PRESENTATION

We report the case of a 31-year-old female diagnosed with anti-NMDA receptor encephalitis from Osaka General Medical Center, Osaka, JAPAN that developed heterotopic ossification of the knees during prolonged coma. She was unable to walk because of pain and limited range of motion in both knees. Thirty months after the onset of the coma, surgical excision of the heterotopic bone in both knees was performed. The range of motion of both the knees improved markedly and she had no recurrence of heterotopic ossification on a three-year follow-up. Thus, this case can be used as a guide for surgeons with such patients.

CONCLUSIONS

We reported a case of heterotopic bone formation in the periarticular region of both bilateral knees in a patient who suffered a 2-month coma following anti-NMDA receptor encephalitis. Surgical excision of the heterotopic bones significantly improved the passive range of motion in both knees. Three years after the operation, the patient had no complaints about her knees, and there was no recurrence of HO.

Burn-induced heterotopic ossification from incidence to therapy: key signaling pathways underlying ectopic bone formation

Burn injury is one of the potential causes of heterotopic ossification (HO), which is a rare but debilitating condition. The incidence ranges from 3.5 to 5.6 depending on body area. Burns that cover a larger percentage of the total body surface area (TBSA), require skin graft surgeries, or necessitate pulmonary intensive care are well-researched risk factors for HO. Since burns initiate such complex pathophysiological processes with a variety of molecular signal changes, it is essential to focus on HO in the specific context of burn injury to define best practices for its treatment. There are numerous key players in the pathways of burn-induced HO, including neutrophils, monocytes, transforming growth factor-β1-expressing macrophages and the adaptive immune system. The increased inflammation associated with burn injuries is also associated with pathway activation. Neurological and calcium-related contributions are also known. Endothelial-to-mesenchymal transition (EMT) and vascularization are known to play key roles in burn-induced HO, with hypoxia-inducible factor-1 (HIF-1) and vascular endothelial growth factor (VEGF) as potential initiators. Currently, non-steroidal anti-inflammatory drugs (NSAIDs) and radiotherapy are effective prophylaxes for HO. Limited joint motion, ankylosis and intolerable pain caused by burn-induced HO can be effectively tackled via surgery. Effective biomarkers for monitoring burn-induced HO occurrence and bio-prophylactic and bio-therapeutic strategies should be actively developed in the future.

Extracorporeal shock wave therapy to treat neurogenic heterotopic ossification in a patient with spinal cord injury: A case report

Objective: To evaluate the efficacy and safety of treatment for neurogenic heterotopic ossification (NHO) using extracorporeal shock wave therapy (ESWT) in persons with spinal cord injury (SCI).Design: Single case report.Setting: Department of Physical Medicine and Rehabilitation, Veterans Health Service Medical Center.Participants: A 55-year-old male with cervical SCI, who developed painful NHO around the right hip joint.Interventions: Ultrasound-guided ESWT that used 4,000 shocks at the rate of 3 Hz and the energy flux density between 0.056 and 0.068 mJ/mm² was applied to the NHO region a total of 7 times, weekly.Outcome Measures: We assessed the treatment outcomes using a visual analog scale (VAS) score, wheelchair sitting time and size of NHO.Result: After 7 weeks of ESWT treatment, his pain reduced from a VAS score of 7-8 to 3 and his wheelchair sitting time increased. However, there was no significant change of size of NHO.Conclusion: The application of ESWT could be a possible alternative to other treatments for NHO in persons with SCI.Clinical Trial Registry Number: 2019-03-003.

Investigation into Possible Association of Oxandrolone and Heterotopic Ossification Following Burn Injury

Oxandrolone, a testosterone analog, is used to counteract the catabolic effects of burn injury. Recent animal studies suggest a possible hormonal association with heterotopic ossification (HO) development postburn. This work examines oxandrolone administration and HO development by exploring historical clinical data bridging the introduction of oxandrolone into clinical practice. Additionally, we examine associations between oxandrolone administration and HO in a standardized mouse model of burn/trauma-related HO. Acutely burned adults admitted between 2000 and 2014, survived through discharge, and had a HO risk factor of 7 or higher were selected for analysis from a single burn center. Oxandrolone administration, clinical and demographic data, and elbow HO were recorded and were analyzed with logistic regression. Associations of oxandrolone with HO were examined in a mouse model. Mice were administered oxandrolone or vehicle control following burn/tenotomy to examine any potential effect of oxandrolone on HO and were analyzed by Student's t test. Subjects who received oxandrolone had a higher incidence of elbow HO than those that did not receive oxandrolone. However, when controlling for oxandrolone administration, oxandrolone duration, postburn day oxandrolone initiation, HO risk score category, age, sex, race, burn size, and year of injury, there was no significant difference between rates of elbow HO between the two populations. In agreement with the review, in the mouse model, while there was a trend toward the oxandrolone group developing a greater volume of HO, this did not reach statistical significance.

A Comparison of Contracture Severity at Acute Discharge in Patients With and Without Heterotopic Ossification: A Burn Model System National Database Study

This study assesses the association between heterotopic ossification and upper extremity contracture by comparing goniometric measured active range of motion outcomes of patients with and without heterotopic ossification. Data were obtained from the Burn Model System National Database between 1994 and 2003 for patients more than 18 years with elbow contracture at acute discharge. Absolute losses in elbow range of motion were compared for those with and without radiologic evidence of heterotopic ossification (location undefined) and were further examined by burn size subgroups using Wilcoxon rank-sum test. Differences in elbow range of motion were estimated using regression models, adjusted for demographic and clinical variables. Loss of range of motion of shoulder, wrist, forearm, and hand were also compared. From 407 instances of elbow contracture, the subjects with heterotopic ossification were found to have greater median absolute loss of elbow flexion among all survivors (median 50° [IQR 45°] vs 20° [30°], P < .0001), for the 20 to 40% total body surface area burn subgroup (70° [20°] vs 20° [30°], P = .0008) and for the >40% subgroup (50° [45°] vs 30° [32°], P = .03). The adjusted estimate of the mean difference in the absolute loss of elbow flexion between groups was 23.5° (SE ±7.2°, P = .0013). This study adds to our understanding of the potential effect of heterotopic ossification on upper extremity joint range of motion, demonstrating a significant association between the presence of heterotopic ossification and elbow flexion contracture severity. Further study is needed to determine the functional implications of heterotopic ossification and develop treatment protocols.

Identification of the Biomarkers and Pathological Process of Heterotopic Ossification: Weighted Gene Co-Expression Network Analysis

Heterotopic ossification (HO) is the formation of abnormal mature lamellar bone in extra-skeletal sites, including soft tissues and joints, which result in high rates of disability. The understanding of the mechanism of HO is insufficient. The aim of this study was to explore biomarkers and pathological processes in HO+ samples. The gene expression profile GSE94683 was downloaded from the Gene Expression Omnibus database. Sixteen samples from nine HO- and seven HO+ subjects were analyzed. After data preprocessing, 3,529 genes were obtained for weighted gene co-expression network analysis. Highly correlated genes were divided into 13 modules. Finally, the cyan and purple modules were selected for further study. Gene ontology functional annotation and Kyoto Encyclopedia of Genes and Genomes pathway enrichment indicated that the cyan module was enriched in a variety of components, including protein binding, membrane, nucleoplasm, cytosol, poly(A) RNA binding, biosynthesis of antibiotics, carbon metabolism, endocytosis, citrate cycle, and metabolic pathways. In addition, the purple module was enriched in cytosol, mitochondrion, protein binding, structural constituent of ribosome, rRNA processing, oxidative phosphorylation, ribosome, and non-alcoholic fatty liver disease. Finally, 10 hub genes in the cyan module [actin related protein 3 (ACTR3), ADP ribosylation factor 4 (ARF4), progesterone receptor membrane component 1 (PGRMC1), ribosomal protein S23 (RPS23), mannose-6-phosphate receptor (M6PR), WD repeat domain 12 (WDR12), synaptosome associated protein 23 (SNAP23), actin related protein 2 (ACTR2), siah E3 ubiquitin protein ligase 1 (SIAH1), and glomulin (GLMN)] and 2 hub genes in the purple module [proteasome 20S subunit alpha 3 (PSMA3) and ribosomal protein S27 like (RPS27L)] were identified. Hub genes were validated through quantitative real-time polymerase chain reaction. In summary, 12 hub genes were identified in two modules that were associated with HO. These hub genes could provide new biomarkers, therapeutic ideas, and targets in HO.

Surgical treatment of postburn heterotopic ossification around the elbow: Three case reports

RATIONALE

Heterotopic ossification (HO), which is defined as the formation of new bone in tissues that do not normally ossify, is an infrequent yet debilitating complication of burns. Herein, we report three patients who suffered from elbow HO after burn injury due to a dust explosion event. This is a case report that includes the most cases involved in a single mass casualty incident in the presented literature.

PATIENT CONCERNS

Case 1: A 28-year-old man presented with second-to-third degree 88% total body surface area (TBSA) burns after the explosion event. He complained of decreased progressive bilateral elbow range of motion (ROM) for 1.5 months after the burn injury.Case 2: A 28-year-old woman presented with second-to-third degree 50% TBSA burns and complained of decreased progressive bilateral elbow ROM with intolerable pain on elbow extension for 1 month after the burn injury.Case 3: A 22-year-old man presented with second-to-third degree 90% TBSA burns and complained of significantly decreased left elbow ROM with intolerable pain 5 months after the burn injury.

DIAGNOSIS

The follow-up radiograph of the symptomatic elbow of these three patients revealed heterotopic ossification formation. Three-dimensional reconstruction computed tomography performed preoperatively showed that HO mainly affected the humeroulnar joint.

INTERVENTIONS

We treated all three patients with surgical elbow HO resection and ulnar nerve transposition, followed by immediate passive ROM exercise since postoperative day 1 and continuous physical therapy.

OUTCOMES

In case 1, the documented ROM gain on the last follow-up (18.5 months after surgery) was 30° in the right elbow and 118° in the left elbow. In case 2, the follow-up time was 21 months and the documented ROM gain on the last follow-up was 120° in the right elbow and 90° in the left elbow. In case 3, the follow-up time was 20 months and the documented left elbow ROM gain on the last follow-up was 40°.

LESSONS

We discuss our experience of treating postburn HO and review the recent literature. The postburn HO treatment results of early surgical excision combined with immediate postoperative physical therapy were satisfactory.

Heterotopic ossification and the elucidation of pathologic differentiation

Tissue regeneration following acute or persistent inflammation can manifest a spectrum of phenotypes ranging from the adaptive to the pathologic. Heterotopic Ossification (HO), the endochondral formation of bone within soft-tissue structures following severe injury serves as a prominent example of pathologic differentiation; and remains a persistent clinical issue incurring significant patient morbidity and expense to adequately diagnose and treat. The pathogenesis of HO provides an intriguing opportunity to better characterize the cellular and cell-signaling contributors to aberrant differentiation. Indeed, recent work has continued to resolve the unique cellular lineages, and causative pathways responsible for ectopic bone development yielding promising avenues for the development of novel therapeutic strategies shown to be successful in analogous animal models of HO development. This review details advances in the understanding of HO in the context of inciting inflammation, and explains how these advances inform the current standards of diagnosis and treatment.

Is heterotopic ossification getting nervous?: The role of the peripheral nervous system in heterotopic ossification

Heterotopic ossification (HO), or de novo bone formation in soft tissue, is often observed following traumatic injury. Recent studies suggest that peripheral nerves may play a key functional role in this process. The results supporting a neurological basis for HO are examined in this article. Evidence supports the fact that BMPs released from bone matrix possess the capacity to induce HO. However, the process cannot be recapitulated using recombinant proteins without extremely high doses suggesting other components are required for this process. Study of injuries that increase risk for HO, i.e. amputation, hip replacement, elbow fracture, burn, and CNS injury suggests that a likely candidate is traumatic injury of adjacent peripheral nerves. Recent studies suggest neuroinflammation may play a key functional role, by its ability to open the blood-nerve barrier (BNB). Barrier opening is characterized by a change in permeability and is experimentally assessed by the ability of Evans blue dye to enter the endoneurium of peripheral nerves. A combination of BMP and barrier opening is required to activate bone progenitors in the endoneurial compartment. This process is referred to as "neurogenic HO".

Our 35 years' experience on postburn heterotopic ossification: A three-step treatment

Our retrospective study of burn patients presents a three-step treatment of heterotopic ossification: excision surgery, early rehabilitation, and analgesia. We included patients admitted to the department for treatment of postburn heterotopic ossification between January 1, 1979, and September 30, 2015. The mean age at the time of the burn was 43.3 years. Men accounted for the majority of burn patients who developed an osteoma (70.8%). The mean total skin area burned was 38.4%. No osteoma justifying surgery was found for any patient with a total burned skin area less than 19%. The burned zones were related to the osteoma development in 94.3% of cases. On average, the surgery took place 10.8 months after the burn. The osteotomy was accompanied by surgical treatment of a contracture in 37.1% of patients. Most of the osteomata were found at the elbows (30), followed by the shoulders (3), and finally the knees (2). Rehabilitation began on D0 after the surgery, except if a flap or a thin-skin graft was used. Regarding analgesia, opiates were prescribed systematically during the immediate postoperative period. Elbow range of motion on flexion improved by a mean of 84.1°. During the postoperative period, we found 2 recurrences of osteoma and 1 elbow hematoma in two separate patients. There were no postoperative infections or neurological sequelae. Our retrospective French study confirmed results found in the international literature. The three-step treatment - excision surgery, early rehabilitation, and antalgia - seems to be the best means of treating osteoma with satisfactory results. Surgery is indicated only in the case of functional impairment and not simply based on imaging.

Rehabilitation of the Complex Burn Patient with Multiple Injuries or Comorbidities

Patients with complex burn injuries require interdisciplinary rehabilitation to maximize their functional recovery. Successful rehabilitation from burn injuries starts with addressing the loss of the protective, mechanical, and cosmetic function of the skin and underlying structures. However, other injuries, particularly to the nervous and musculoskeletal systems, need to be identified and managed as part of the rehabilitation plan. Burn injuries can cause losses of functional mobility, self-care skills, psychological well-being, and community participation, which require comprehensive rehabilitation interventions throughout the recovery process.

Heterotopic Ossification and Hypertrophic Scars

Burns and trauma cause superficial and deep soft tissue wounds that cannot heal to the preinjury state. Healing requires cell proliferation and differentiation into the injured tissue type, laying down extracellular matrix, often as collagens. Heterotopic ossification causes severe pain, nonhealing wounds, and restricted range of motion. Treatment includes radiation therapy, nonsteroidal anti-inflammatory drugs, bisphosphonates, and possibly surgical excision and prophylactic measures. Hypertrophic scars, nonosseous lesions caused by excessive collagen deposition, are often painful, functionally limiting, and aesthetically displeasing. Treatment includes CO2 laser application, steroid injections, and excision with skin grafting. This article reviews the management of these pathologic wounds.

Important Developments in Burn Care

LEARNING OBJECTIVES

After studying this article, the participant should be able to: 1. Explain the epidemiology of severe burn injury in the context of socioeconomic status, gender, age, and burn cause. 2. Describe challenges with burn depth evaluation and novel methods of adjunctive assessment. 3. Summarize the survival and functional outcomes of severe burn injury. 4. State strategies of fluid resuscitation, endpoints to guide fluid titration, and sequelae of overresuscitation. 5. Recognize preventative measures of sepsis. 6. Explain intraoperative strategies to improve patient outcomes, including hemostasis, restrictive transfusion, temperature regulation, skin substitutes, and Meek skin grafting. 7. Translate updates in the pathophysiology of hypertrophic scarring into novel methods of clinical management. 8. Discuss the potential role of free tissue transfer in primary and secondary burn reconstruction.

SUMMARY

Management of burn-injured patients is a challenging and unique field for plastic surgeons. Significant advances over the past decade have occurred in resuscitation, burn wound management, sepsis, and reconstruction that have improved outcomes and quality of life after thermal injury. However, as patients with larger burns are resuscitated, an increased risk of nosocomial infections, sepsis, compartment syndromes, and venous thromboembolic phenomena have required adjustments in care to maintain quality of life after injury. This article outlines a number of recent developments in burn care that illustrate the evolution of the field to assist plastic surgeons involved in burn care.

Vascular patterning in human heterotopic ossification

Heterotopic ossification (HO, also termed myositis ossificans) is the formation of extra-skeletal bone in muscle and soft tissues. HO is a tissue repair process gone awry, and is a common complication of surgery and traumatic injury. Medical strategies to prevent and treat HO fall well short of addressing the clinical need. Better characterization of the tissues supporting HO is critical to identifying therapies directed against this common and sometimes devastating condition. The physiologic processes of osteogenesis and angiogenesis are highly coupled and interdependent. However, few efforts have been made to document the vascular patterning within heterotopic ossification. Here, surgical pathology case files of 29 human HO specimens were examined by vascular histomorphometric analysis. Results demonstrate a temporospatial patterning of HO vascularity that depends on the "maturity" of the bony lesion. In sum, human HO demonstrates a time- and space-dependent pattern of vascularization suggesting a coupled pathophysiologic process involving the coordinate processes of osteogenesis and angiogenesis. Further imaging studies may be used to further characterize vasculogenesis within HO and whether anti-angiogenic therapies are a conceivable future therapy for this common condition.

Heterotopic Ossification Following Upper Extremity Injury

Heterotopic ossification (HO) presents a substantial barrier to rehabilitation for patients with severe burns or trauma. Although surgical excision is a mainstay of management for this condition, this is unable to address the chronic sequelae of HO, including chronic pain, joint contractures, nerve dysfunction, and open wounds. Current therapeutic modalities are aimed at excision and the prevention of recurrence using nonsteroidal antiinflammatory drugs (NSAIDs) or radiation therapy. Research is now focused on identifying alternative strategies to prevent the initial occurrence of HO through NSAIDs and novel inhibitors of the bone morphogenetic protein signaling pathway.

The development and impact of heterotopic ossification in burns: a review of four decades of research

Background to this subject:

Heterotopic ossification (HO) is the formation of bone within the tissue where bone should not form and is a rare complication after burn injury. However, it leads to severe pain and distress, marked reduction in joint range of motion (ROM), impaired function and increased hospital length of stay. The pathophysiology, incidence and risk factors of HO remain poorly understood in burns and other traumas and the management, controversial.

Question being asked or issue explored:

The aim of this comprehensive review was to synthesise the available evidence on the development and treatment of HO after acute burn injury.

Details of how the work was conducted:

The review was based on a systematic search of medical electronic databases to identify relevant published literature.

What we did and did not learn from this study:

Synthesis and analysis of the data highlighted that, despite the passage of time, little translatable evidence is available to guide any prevention, screening, diagnostic or pharmacological or physical management protocols. Causes of HO remain confounded, therefore prevention is difficult. Although spontaneous resolution is possible, surgical resection remains the recommended treatment when ROM and activities of daily living are severely affected. The findings from this review indicate that multicentre data pooling is needed to understand the optimum pathway to prevention, identification and treatment of HO in acute burn patients.

Risk Factors in Hospitalized Patients With Burn Injuries for Developing Heterotopic Ossification--A Retrospective Analysis

The aims of this study were to identify the risk factors for developing heterotopic ossification in patients with burns injuries and, second, to review the outcomes associated with the treatment disodium etidronate. Patients with heterotopic ossification were identified using the burns unit computer database. The control group was the patients who were the next admission after admission of the patient who subsequently developed heterotopic ossification. Demographic and clinical data were collected. Univariate and multivariate techniques were used to identify risk factors for heterotopic ossification. We reviewed 337 patients admitted over a 5-year period and identified 19 patients with heterotopic ossification (5.6%). A further 19 burn injury patients were included as controls. Heterotopic ossification developed clinically and radiologically after a median time of 37 days (interquartile range [IQR], 30-40) and 49 days (IQR, 38-118), respectively. In univariate analysis, heterotopic ossification was associated with a greater %TBSA, inhalation injury, use of mechanical ventilation, number of surgical procedures, sepsis, and longer time to active movement. In a multivariate analysis that adjusted for severity of burn injury by means of the Belgian Outcome in Burn Injury score, time to active movement was recognized as an independent risk factor for heterotopic ossification (odds ratio 1.48, 95% confidence interval 1.09-2.01). Elevations in serum calcium concentrations were the only observed adverse effects for disodium etidonrate. This study has demonstrated that %TBSA, inhalation injury, and the need for ventilatory support and the use of multiple surgical procedures are predictive of the development of heterotopic ossification.

Corrective and reconstructive surgery in patients with postburn heterotopic ossification and bony ankylosis: an evidence-based approach

Articular heterotopic ossification (HO) and subsequent bony ankylosis (BA) are infrequent yet devastating complications of severe burn injuries. These conditions are diagnosed clinically and confirmed by imaging. Patients then begin active physical therapy until cleared for surgery, which remains the standard of care. This study critically reviews the existing literature on the diagnosis, treatment, and surgical outcomes of HO/BA in severely burned patients and provides an evidence-based treatment algorithm. A comprehensive search for all the studies addressing HO and BA after burn injury was conducted using PubMed and Google Scholar from 1957 to 2013. Fifty-one studies on postburn HO/BA have been published, reporting incidences from 0.1 to 35.3%. Most patients suffered from third-degree, thermal burns, with a mean TBSA of 49 ± 14%. The mean time from burn until diagnosis was 7 ± 11 months. Seventy-nine percent of the affected joints were elbows and 84% had adjacent and/or overlying burns. Ninety-one percent of joints had solely extra-articular HO. Ninety percent of HO/BA cases were treated with anatomic excision, and all achieved appreciable increases in range of motion with infrequent recurrence. Perioperative radiotherapy was used infrequently. Surgical articular reconstruction is the standard of care for postburn HO/BA severe enough to limit joint movement and/or function. Early detection and initiation of physical therapy are paramount in preventing progression to complete BA. Increased awareness and more rapid means of detecting postburn articular changes may permit earlier discontinuation of passive range of motion exercises, thereby halting the initiation and progression of HO.

Heterotopic Ossification: Basic-Science Principles and Clinical Correlates

➤ Heterotopic ossification occurs most commonly after joint arthroplasty, spinal cord injury, traumatic brain injury, blast trauma, elbow and acetabular fractures, and thermal injury.➤ The conversion of progenitor cells to osteogenic precursor cells as a result of cell-mediated interactions with the local tissue environment is affected by oxygen tension, pH, availability of micronutrients, and mechanical stimuli, and leads to heterotopic ossification.➤ Radiation and certain nonsteroidal anti-inflammatory medications are important methods of prophylaxis against heterotopic ossification.➤ Well-planned surgical excision can improve patient outcomes regardless of the joint involved or the initial cause of injury.➤ Future therapeutic strategies are focused on targeted inhibition of local factors and signaling pathways that catalyze ectopic bone formation.

Radiotherapy for the prophylaxis of heterotopic ossification: a systematic review and meta-analysis of published data

INTRODUCTION

Following surgery, the formation of heterotopic ossification (HTO) can limit mobility and impair quality of life. Radiotherapy has been proven to provide efficacious prophylaxis against HTO, especially in high-risk settings.

PURPOSE

The current review aims to determine the factors influencing HTO formation in patients receiving prophylactic radiotherapy.

METHODS

A systematic search of the literature was conducted on Ovid Medline, Embase and the Cochrane Central Register of Controlled Trials. Studies were included if they reported the percentage of sites developing heterotopic ossification after receiving a specified dose of prophylactic radiotherapy. Weighted linear regression analysis was conducted for continuous or categorical predictors.

RESULTS

Extracted from 61 articles, a total of 5464 treatment sites were included, spanning 85 separate study arms. Most sites were from the hip (97.7%), from United States patients (55.2%), and had radiation prescribed postoperatively (61.6%) at a dose of 700cGy (61.0%). After adjusting for radiation site, there was no statistically significant relationship between the percentage of sites developing HTO and radiation dose (p=0.1) or whether radiation was administered preoperatively or postoperatively (p=0.1). Sites with previous HTO formation were more likely to develop recurrent HTO than those without previous HTO formation (p=0.04). There was a statistically significant negative relationship between the HTO development and the cohort mean year of treatment (p=0.007).

CONCLUSION

Decreases in rates of HTO over time in this patient population may be a function of more efficacious surgical regimens and prophylactic radiotherapy.

Heterotopic ossification of the elbow treated with surgical resection: risk factors, bony ankylosis, and complications

BACKGROUND

Heterotopic ossification is the most common extrinsic cause of elbow contracture and may lead to clinically important stiffness, and rarely, complete bony ankylosis. Surgery sometimes is performed to treat this problem, and published reports differ regarding the factors that are associated with success or failure after this operation and whether the procedure is effective for patients with elbow ankylosis.

QUESTIONS/PURPOSES

We wished (1) to identify potential patient characteristics and modifiable risk factors that are associated with improvements in ROM after surgery for heterotopic ossification of the elbow; (2) to compare ROM gains between patients with complete ankylosis and partially restricted ROM; and (3) to characterize the complications of elbows treated by surgical release and excision of heterotopic ossification followed by a standardized rehabilitation program.

METHODS

We reviewed the records of all patients treated operatively for heterotopic ossification of the elbow from September 1999 to February 2012 at one institution by one surgeon. General indications for the surgery were clinically symptomatic or debilitating heterotopic ossification of the elbow. Each patient received prophylaxis postoperatively consisting of indomethacin (or single-shot radiation for patients with sensitivity to antiinflammatory medications). All patients received a physical therapy regimen and used a continuous passive motion machine for 6 weeks. Patient demographics, mechanism of injury, time between injury and surgery, and medical history were reviewed for comparison. Followup was at a mean of 13 months (range, 3-106 months); no patients were lost to followup. Thirty-nine patients (46 elbows) with heterotopic ossification treated with excision were identified: 10 patients (16 elbows) had burns, 28 patients (29 elbows) had trauma, and one patient (one elbow) had a closed head injury. Eight of the 39 patients (12 of 46 elbows [26%]) had complete ankylosis at the time of surgery.

RESULTS

Hypertension, obesity, and absence of intraoperative anterior ulnar nerve transposition were associated with an adverse effect on change from preoperative to final arc of motion. The group with ankylosis had greater preoperative to postoperative gain in arc compared with the group with partial restriction (96°, 95% CI, 84°-107° and 59°, 95% CI, 46°-72°, respectively). For the entire cohort there was an overall improvement in mean flexion-extension arc of motion from 35° to 103° at final followup (p < 0.001; 95% CI, 57°-80°), with a 17% rate of complications (three patients [three elbows] with heterotopic ossification, three patients [three elbows] with nerve palsies, one patient [one elbow] with deep wound infection, and one patient [one elbow] with an unstable elbow).

CONCLUSIONS

Patients with partially and completely restricted ROM showed substantial improvement in postoperative ROM. Hypertension, obesity, and absence of intraoperative anterior ulnar nerve transposition were negative predictors of outcome in our series. Surgery combined with postoperative prophylaxis and a regimented rehabilitation program are feasible modalities to treat patients with heterotopic ossification of the elbow.

LEVEL OF EVIDENCE

Level IV, therapeutic study. See the Instructions for Authors for a complete description of levels of evidence.

Improvements in elbow motion after resection of heterotopic bone: a systematic review

Complex elbow trauma, severe burn, or a closed head injury render patients at risk for developing heterotopic ossification around the elbow. When heterotopic ossification restricts elbow motion, some patients request surgical resection. We performed a systematic review of the literature to analyze improvement in elbow motion after resection of heterotopic ossification around the elbow. We found that, on average, etiology had little impact on outcome after resection of heterotopic ossification. Resection of heterotopic bone generally leads to improvement of elbow function.

Prevention and treatment of elbow stiffness: a 5-year update

Elbow stiffness is a challenging and common problem faced by upper extremity surgeons. Although functional improvements can be made with both nonsurgical and surgical management strategies, physicians must remain vigilant with efforts to prevent stiffness before it starts. Recent advancements in the biology and pathology of elbow contracture have led to improved understanding of this difficult problem, and they may lead to future breakthroughs in the prevention and treatment of elbow stiffness. This article serves as an update to our previous review of elbow stiffness, focusing on recent advancements in the past 5 years, as well as updating our current algorithm for treatment.

Radiotherapy for prevention of heterotopic ossification of the elbow: a systematic review of the literature

BACKGROUND

Heterotopic ossification is a pathological process characterized by abnormal formation of bone in nonskeletal tissue. Radiotherapy for heterotopic ossification of the elbow is questionable because of possible adverse effects.

METHODS

A systematic review of the literature was conducted in MEDLINE, Scopus, ISI Web of Science, National Institute for Health and Clinical Excellence, National Guideline Clearinghouse, System for Information on Grey Literature in Europe, ClinicalTrials.gov, Cochrane Central Register of Clinical Trials, and Cochrane Database of Systematic Reviews up to April 2012. All published articles assessing interventions including radiotherapy for prevention of heterotopic ossification in the elbow of adult patients were considered. Information was recorded by the first two authors, and disagreements in interpretation were resolved by consensus.

RESULTS

In total, 27 studies using radiotherapy for elbow heterotopic ossification were identified (1 randomized clinical trial, 1 case-control study, and 25 case reports and case series) in the literature. Most of them used a single dose of 7.0 Gy. The randomized clinical trial was stopped early because of severe adverse effects (pseudarthrosis) caused by radiation. The case-control study showed that radiotherapy did not effectively prevent recurrence of heterotopic ossification. The case reports and case series mentioned only sparse adverse events.

CONCLUSION

The use of radiation therapy for prevention of heterotopic ossification of the elbow is supported by weak evidence.

Clinical results of the excision of heterotopic bone around the elbow: a systematic review

BACKGROUND

Heterotopic ossification (HO) of the elbow can occur following direct trauma, brain injury, or burns. Development of elbow HO is sporadic, making levels 1-3 clinical evidence difficult to establish. We systematically reviewed literature regarding management and outcomes of surgically treated elbow HO.

METHODS

A systematic review of the literature regarding elbow HO was performed to compare imaging modalities, surgical timing, surgical approaches, and methods of prophylaxis in outcomes of patients treated with excision.

RESULTS

Our systematic review included 24 level 3 or 4 studies investigating 384 post-trauma (158), brain injury (105), or burn (94) patients with elbows complicated by HO that were treated with surgical excision. Average patient age was 36.9 years and there was a 65/35 M/F ratio. For all etiologies, preoperatively elbow flexion/extension averaged 53/83; postoperatively elbow flexion/extension significantly improved to 22/123. Regardless of the etiology, surgical excision of elbow HO significantly improved functional range of motion. Neither total body surface area (TBSA) burned for burn patients or Garland classification for brain-injured patients correlated with outcome. Overall complication rate was 22.6% and included HO recurrence (11.9%), ulnar nerve injury, infection, and delayed wound healing.

CONCLUSION

Surgical treatment of elbow HO leads to improved functional outcome, whether the etiology of bone formation was direct elbow trauma, brain injury, or thermal injury.

Safety and efficacy of radiation therapy as secondary prophylaxis for heterotopic ossification of non-hip joints

INTRODUCTION

Prophylactic radiation therapy (RT) is an established adjuvant therapy for heterotopic ossification (HO) of the hip when delivered in the immediate pre- or postoperative setting. Its role in prevention of recurrence after excision of HO is supported by randomised trials for HO of the hip, but there is scant evidence to demonstrate the safety and efficacy of a similar approach in non-hip joints. In the current study, we evaluate radiological and functional outcomes after prophylactic RT for prevention of HO of the knee and upper extremity.

METHODS

With institutional review board (IRB) approval, patients treated at our institution with prophylactic RT for non-hip HO from 1998 to 2009 were identified. Records were reviewed, including pre- and postoperative records, operative reports and radiography. The primary objectives were to determine the safety of RT and rate of treatment failure, as defined by need for further surgical intervention.

RESULTS

A total of 30 patients received prophylactic RT for HO of the elbow (n=21), MCP joint (n=1) and knee (n=8). Twenty-nine of the 30 patients were treated within 24-48h postoperatively, and one patient was treated within 24h preoperatively. Based on institutional policy, only patients considered to be at high risk of recurrence were selected to receive prophylactic RT. Patients were treated to a dose of 7Gy in one fraction, with two parallel opposed. Complications following treatment included two patients with postoperative wound infections, one patient with a ruptured triceps tendon and one patient with a fracture within the treatment field. Follow-up information was available for 26 of 30 patients, with a median follow-up time of 16months (range, 2-143months). Recurrent HO, requiring surgical re-excision, developed in 10.5% (n=2) of patients who were followed for upper extremity HO (n=19). For patients followed after RT for HO of the knee (n=7), there were no recurrences of HO that required further intervention.

CONCLUSION

In this group of patients at high risk for developing further HO, prophylactic RT appears to be a safe adjunct to surgery and is effective in prevention of HO recurrence. Results are similar to published reports of HO of the hip and support the use of surgical excision and perioperative, prophylactic RT for HO of non-hip joints.