Heterotopic ossification of the elbow in patients with burns. Results after early excision

Surgical Management of Chronic Neuropathic Burn Pain

Burn-related chronic neuropathic pain can contribute to a decreased quality of life. When medical and pharmacologic therapies prove ineffective, patients should undergo evaluation for surgical intervention, consisting of a detailed physical examination and elective diagnostic nerve block, to identify an anatomic cause of pain. Based on symptoms and physical examination findings, particularly Tinel's sign, treatments can vary, including a trial of laser therapies, fat grafting, or nerve surgeries (nerve decompression, neuroma excision, targeted muscle reinnervation, regenerative peripheral nerve interfaces, and vascularized denervated muscle targets). It is essential to counsel patients to establish appropriate expectations prior to treatment with a multidisciplinary team.

A scoping review on active vs. passive range of motion approaches to treat heterotopic ossification at the elbow

Objective

The objective of this scoping review is to synthesize and clarify literature on the effectiveness of active and passive range of motion therapy techniques to address range of motion in people with heterotopic ossification (HO), and to provide guidance to therapists in clinical decision-making based on current evidence.

Method

To find articles that included therapeutic interventions to maintain or improve range of motion in people with heterotopic ossification, the authors searched the following databases: Cochrane Database of Systematic Reviews, PubMed, CINAHL, PsychINFO, Web of Science, and OTSeeker. To ensure that the search was comprehensive, the authors also searched Burns and Trauma, Burns Journal, Burns Open, and the Journal of Hand Therapy. Searches were limited to peer-reviewed articles published in the English language. No publication date limits were set. The Physiotherapy Evidence Database PEDro scale was utilized to measure the validity of the methodological quality of each article.

Results

Five studies met the inclusion criteria.. Two studies emphasized that passive range of motion was effective in less than 50% of their subjects, while the other three studies utilized active range of motion only, reporting 50% of patients did not require surgery.

Discussion/conclusion

There is insufficient evidence to determine effective therapeutic management of HO and the literature that does exist is contradictory and inconclusive. Future research is necessary to determine if any effectiveness of manual therapeutic approaches exists for patients with HO.

Heterotopic Ossification around the Elbow Revisited

Heterotopic ossification (HO) is the process of ectopic bone formation in the periarticular soft tissues and is usually formed in the elbow, hip and knee joint as a complication of trauma, burns, brain injury or surgical procedures. The development of HO around the elbow joint can cause a severe limitation of range of motion (ROM) and may affect daily activities of the patient. Treatment of ectopic bone formation around the elbow is a challenge for many surgeons. Non-operative treatment usually fails to restore the ROM of the elbow joint; thus, surgery is necessary to restore the function of the joint. In the past, many surgeons suggested that a delayed excision of HO, until maturation of the ectopic bone, is the best option in order to avoid any possible recurrence. However, many authors now suggest that this delay may lead to complications such as muscular atrophy and formation of soft tissue contractures that can cause a greater impairment of elbow function; thus, early excision is a better option and can better restore the elbow ROM. We performed a literature research of articles that investigated which is the best time of HO excision and we also evaluated if the tethering effect of HO can lead to a greater impairment of the elbow function. We found numerous studies suggesting that a limitation in ROM of the elbow can appear from the tethering of the ectopic bone formation and not only from primary HO. Concerning the HO excision, there were no significant differences between patients who underwent delayed and early excision, concerning the recurrence rate of HO around the elbow. Patients who underwent early excision had better restoration of elbow ROM; thus, early excision, combined with a rehabilitation program, is reported to be the best option for these patients.

Pediatric Heterotopic Ossification: A Comprehensive Review

PURPOSE OF REVIEW

The purpose of this review is to provide a comprehensive analysis of heterotopic ossification (HO) in pediatric patients, including an in-depth examination of the risk factors associated with this condition, current prophylactic measures, and available management strategies.

RECENT FINDINGS

HO is a medical disorder in which bone tissue inexplicably develops in soft tissues such as muscles and tendons. It involves the formation of mature, lamellar bone in extra-skeletal soft tissue, and its formation is influenced by oxygen tension, pH, the availability of micronutrients, and mechanical stimulation. HO has many cellular origins, with the most common theory being multipotent cells in local tissue. The diagnosis of HO is typically made based on exam, radiographs, and CT. Management includes both prophylactic nonsurgical options and surgical resection for severe or recalcitrant cases. The review highlights the incidence, risk factors, and management strategies associated with HO in pediatric patients. HO is a rare condition in children, with severe neurologic injury being the most common cause. Pediatric patients most commonly develop HO following severe neurologic injury, followed by trauma and surgery. Current prophylactic measures, include nonsteroidal anti-inflammatory drugs and radiation therapy though limited literature on their use in the pediatric population exists. For recalcitrant symptomatic cases, wide surgical resection can be considered but has a higher risk profile and associated morbidity. This review highlights the need for further pediatric specific research to inform guidelines and management strategies for this debilitating condition.

Heterotopic Ossification after Trauma

Heterotopic ossification (HO) refers to benign ectopic bone formation in soft tissue and is common following trauma surgery. HO bone can restrict movement and progress into ankylosis that may necessitate surgical intervention. This article discusses the current literature on the pathophysiology, prophylaxis, treatment, and epidemiology of postoperative HO following orthopedic trauma.

Periarticular calcifications

Periarticular calcification and ossification is a frequent finding on imaging and may sometimes pose a diagnostic challenge. The differential diagnoses for this radiological finding are wide and can be classified into broad groups such as idiopathic, developmental, trauma, burns, infection, tumor, connective tissue disease, crystalline, metabolic, vascular, and foreign bodies. With careful consideration of the clinical and imaging findings as well as awareness of mimickers of periarticular mineralization, the list of differential diagnoses can be narrowed down. This article aims to review the clinical-radiologic findings of periarticular calcified or ossified lesions with relevant imaging illustrations.

Neurological heterotopic ossification: novel mechanisms, prognostic biomarkers and prophylactic therapies

Neurological heterotopic ossification (NHO) is a debilitating condition where bone forms in soft tissue, such as muscle surrounding the hip and knee, following an injury to the brain or spinal cord. This abnormal formation of bone can result in nerve impingement, pain, contractures and impaired movement. Patients are often diagnosed with NHO after the bone tissue has completely mineralised, leaving invasive surgical resection the only remaining treatment option. Surgical resection of NHO creates potential for added complications, particularly in patients with concomitant injury to the central nervous system (CNS). Although recent work has begun to shed light on the physiological mechanisms involved in NHO, there remains a significant knowledge gap related to the prognostic biomarkers and prophylactic treatments which are necessary to prevent NHO and optimise patient outcomes. This article reviews the current understanding pertaining to NHO epidemiology, pathobiology, biomarkers and treatment options. In particular, we focus on how concomitant CNS injury may drive ectopic bone formation and discuss considerations for treating polytrauma patients with NHO. We conclude that understanding of the pathogenesis of NHO is rapidly advancing, and as such, there is the strong potential for future research to unearth methods capable of identifying patients likely to develop NHO, and targeted treatments to prevent its manifestation.

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.

Early resection of ectopic bone in patients with heterotopic ossification about the hip after trauma

OBJECTIVES

Heterotopic ossification (HO) is a common complication in patients who have sustained high-energy trauma to the hip region. Traditionally, resection is performed after ectopic bone maturation. We hypothesized that early HO resection in patients with hip ankylosis after trauma can be performed with little chance of recurrence.

DESIGN

Retrospective clinical cohort.

SETTING

Level I Trauma Center PATIENTS/PARTICIPANTS: 14 patients with resection of HO about the hip performed by the senior author during a six-year period.

INTERVENTION

Early resection of Brooker Class III or IV HO.

MAIN OUTCOME MEASUREMENTS

The original injuries, risk factors for HO, post-traumatic clinical course including the workup for HO, times from fixation to resection, surgical approach, and complications were recorded. Records were reviewed to document pre and postoperative hip motions. Pre and post-operative x-rays and CT scans were reviewed to classify the HO and localize the ectopic mass.

RESULTS

Mean injury to resection interval was 6.8-months. Nine of 14 (64%) patients were followed for a mean of 32.9-months post-resection. Indications for resection included pain, stiffness, and evolving sciatic nerve lesions. Risk factors were male gender, brain injury, and extended iliofemoral and Kocher-Langenbeck surgical approaches. Complications included gluteal vein laceration, draining wounds, and recurrence. Mean flexion-extension arc of motion was 18° (range = 0-70°) preoperatively, 100° (range = 85-125°) intra-operatively, and 94° (range = 20-110°) at final follow-up. HO recurred in nine patients; functionally significant in one.

CONCLUSION

Early resection of HO around the hip may be performed with little chance of symptomatic recurrence.

LEVEL OF EVIDENCE

This is a Level IV retrospective case series.

Prevalence and associated predictors for patients developing chronic neuropathic pain following burns

BACKGROUND

Chronic pain, unrelated to the burn itself, can manifest as a long-term complication in patients sustaining burn injuries. The purpose of this study was to determine the prevalence of chronic neuropathic pain (CNP) and compare burn characteristics between patients who developed CNP and patients without CNP who were treated at a burn center.

METHODS

A single-center, retrospective analysis of 1880 patients admitted to the adult burn center was performed from 1 January 2014 to 1 January 2019. Patients included were over the age of 15 years, sustained a burn injury and were admitted to the burn center. CNP was diagnosed clinically following burn injury. Patients were excluded from the definition of CNP if their pain was due to an underlying illness or medication. Comparisons between patients admitted to the burn center with no pain and patients admitted to the burn center who developed CNP were performed.

RESULTS

One hundred and thirteen of the 1880 burn patients developed CNP as a direct result of burn injury over 5 years with a prevalence of 6.01%. Patients who developed CNP were a significantly older median age (54 years vs. 46 years, p = 0.002), abused alcohol (29% vs. 8%, p < 0.001),abused substances (31% vs. 9%, p < 0.001), were current daily smokers (73% vs. 33%, p < 0.001), suffered more full-thickness burns (58% vs. 43%, p < 0.001), greater median percent of total body surface area (%TBSA) burns (6 vs. 3.5, p < 0.001), were more often intubated on mechanical ventilation (33% vs. 14%, p < 0.001), greater median number of surgeries (2 vs. 0, p < 0.001) and longer median hospital length of stay (LOS) (10 days vs. 3 days, p < 0.001), compared to those who did not develop CNP, respectively. Median patient follow-up was 27 months.

CONCLUSIONS

The prevalence of CNP over 5 years was 6.01% in the burn center. Older ages, alcohol abuse, substance abuse, current daily smoking, greater percent of total body surface area (%TBSA) burns, third degree burns, being intubated on mechanical ventilation, having more surgeries and longer hospital LOS were associated with developing CNP following burn injury, compared to patients who did not develop CNP following burn injury.

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.

Determining the effective timing of an open arthrolysis for post-traumatic elbow stiffness: a retrospective cohort study

Background

Following trauma, the elbow is the most susceptible to restricted motion among all joints. Open arthrolysis is often performed for post-traumatic elbow stiffness if that stiffness does not improve with non-operative management. However, the optimal timing for performing an open arthrolysis remains controversial. The purpose of this study was to compare the outcome (elbow motion and function) and the rate of complications among patients who had undergone early, median and late release procedures to establish an optimal time interval following the injury, after which, an effective open arthrolysis can be performed.

Methods

In this retrospective cohort study, we included total 133 patients, who had undergone open arthrolysis for post-traumatic elbow stiffness. The subjects were divided into 3 groups, with 31 patients in the early release group (arthrolysis performed at 6–10 months after injury), 78 patients in the median release group (at 11–20 months), and 24 patients in the late release group (at > 20 months). The release procedure in all patients was performed by the same surgeon, using the same technique. The general data, functional performance, and complications, if any, were retrospectively documented for all patients and statistically analysed.

Results

The demographic data and disease characteristics of all patients were comparable at baseline. Postoperatively, no significant differences were found among the three groups with respect to the range of motion (p = 0.067), Mayo Elbow Performance Score (p = 0.350) and its ratings (p = 0.329), visual analog scale score for pain (p = 0.227), Dellon classification for ulnar nerve symptoms (p = 0.497), and each discrete complication (all p values > 0.05).

Conclusions

At the final follow-up, our results showed no significant difference in the postoperative elbow motion capacities, functional scores and the rates of complications among patients who had undergone an early, median, and late release. Therefore, we have recommended that an early arthrolysis would be preferable due to its multiple advantages, and the conventionally observed interval of > 1 year after the injury, could be shortened.

Level of evidence

Level III; Retrospective Cohort Design; Therapeutic Study.

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.

Rehabilitation of Burn Injuries: An Update

A major burn is a severe injury with a global impact. Our system of medical evacuation has led to the survival of many severely injured service members. Burn rehabilitation is a complex and dynamic process and will not be linear. Recovery requires a comprehensive, interdisciplinary team-based approach, individually designed to maximize function, minimize disability, promote self-acceptance, and facilitate survivor and family reintegration into the community.

Therapeutic strategies for elbow ankylosis due to heterotopic ossification in patients with severe burns

Background

Heterotopic ossification (HO) occurs frequently in the elbow in burn patients, and extends beyond the anatomical structure. HO of the elbow can cause joint contracture and adversely affect activities of daily living.Currently, there is no effective prophylaxis for HO as the precise underlying mechanism remains unknown. Therefore, there is no choice but to treat HO after it has developed. To date, however, no effective standard treatment has been reported, and therefore treatment methods vary between different facilities. Surgical resection is widely accepted as the only therapeutic option once HO limits functional mobility of the elbow.

Purposes

Based on past reports, we examined our cases and recommend effective therapeutic strategies. We posed the following three questions: (1) Is the surgical intervention effective or detrimental for elbow ankylosis due to HO? (2) What is the best timing for the intervention? (3) What is the most effective postoperative rehabilitation plan?

Methods

We treated three patients with complete ankylosis of the elbow due to HO after severe burn injury using different protocols.

Results

Surgery was performed in two cases and rehabilitation therapy was commenced immediately from the first postoperative day. Both patients showed improvement in the active range of motion in their elbow joints. The other patient did not undergo surgery, and his elbows became fixed in the completely extension position.

Conclusion

Surgical resection is beneficial for elbow ankylosis due to HO after burn injury. Although the exact surgical timing is still controversial, we recommend that surgery should be performed as soon as possible after improving the skin condition around the elbow and confirming the maturation of HO on radiographs. Early rehabilitation and pain control are also important after surgery.

Neurological heterotopic ossification: Current understanding and future directions

Neurological heterotopic ossification (NHO) involves the formation of bone in soft tissue following a neurological condition, of which the most common are brain and spinal cord injuries. NHO often forms around the hip, knee and shoulder joints, causing severe pain and joint deformation which is associated with significant morbidity and reduced quality of life. The cellular and molecular events that initiate NHO have been the focus of an increasing number of human and animal studies over the past decade, with this work largely driven by the need to unearth potential therapeutic interventions to prevent the formation of NHO. This review provides an overview of the present understanding of NHO pathogenesis and pathobiology, current treatments, novel therapeutic targets, potential biomarkers and future directions.

Appropriate excision time of heterotopic ossification in elbow caused by trauma

OBJECTIVE

The aim of this study was to investigate the optimal timing for the resection of heterotopic ossification (HO) of the elbow.

METHODS

We retrospectively reviewed 42 patients who were treated operatively for heterotopic ossification of the elbow from March 2010 to December 2014 at our institution. The patients were divided into early (before 12 months) and late (after 12 months) excision groups. In the early excision group (17 patients), the average time from the initial injury to HO excision was 7.4 (3-11) months, and in the late excision group (25 patients), the average time was 33.5 (12-240) months. Every patient was evaluated by range of motion (ROM), the Mayo Elbow Performance Score (MEPS), postoperative complications and HO recurrence.

RESULTS

The preoperative mean ROM in the late excision group was greater than that of the early excision group, suggesting that the ROM is expected to increase even without surgery. Both early and late surgery increased ROM and MEPS, but early surgery improved ROM and MEPS more than late surgery did (p < .05).

CONCLUSIONS

Early excision of HO can provide better elbow function, as indicated by ROM and MEPS. Considering that there were no notable differences in postoperative ROM and MEPS, HO recurrence, or postoperative complications, we concluded that early excision is safe and that the time from an elbow injury to surgery may be shortened.

LEVEL OF EVIDENCE

Level III, therapeutic study.

The timing of open surgical release of post-traumatic elbow stiffness: A systematic review

BACKGROUND

Open release of post-traumatic elbow stiffness is effective in restoring elbow function, but there is no guideline on the optimal time point of surgical release so far. The purpose of this article was to summarize the current available literature reporting on the timing of open release of post-traumatic elbow stiffness.

METHODS

The PubMed, Cochrane Library, and EMBASE were searched with a set of predefined inclusion and exclusion criteria. Manual searches for references were performed to find potential relevant studies. Two authors separately extracted data from all the articles selected.

RESULTS

27 articles published between 1989 and 2017 were included with an overall enrollment of 836 patients. We divided all included studies into 3 groups according to the timing of surgical release: group 1 (6-10 months after injury), group 2 (11-20 months after injury), and group 3(>20 months after injury). The mean postoperative Mayo Elbow Performance Score (MEPS) and recurrence rate were similar among the 3 groups; however, the mean gain in arc of motion in group 1 was the highest with the lowest complication rate among the 3 groups.

CONCLUSION

There was a trend toward a shorter waiting time from injury to open arthrolysis from 12 months to 6 months. The shorter waiting period of 6 to 10 months yielded better results. Therefore, early surgical release of stiff elbows is recommended for a shorter rehabilitation time and earlier return to work.

LEVEL OF EVIDENCE

Level IV, Systematic Review.

Peripheral Neuropathy and Nerve Compression Syndromes in Burns

Peripheral neuropathy and nerve compression syndromes lead to substantial morbidity following burn injury. Patients present with pain, paresthesias, or weakness along a specific nerve distribution or experience generalized peripheral neuropathy. The symptoms manifest at various times from within one week of hospitalization to many months after wound closure. Peripheral neuropathy may be caused by vascular occlusion of vasa nervorum, inflammation, neurotoxin production leading to apoptosis, and direct destruction of nerves from the burn injury. This article discusses the natural history, diagnosis, current treatments, and future directions for potential interventions for peripheral neuropathy and nerve compression syndromes related to burn injury.

Predicting Heterotopic Ossification Early After Burn Injuries: A Risk Scoring System

OBJECTIVE

The purpose of this study is to develop a scoring system that stratifies burn patients at the time of hospital admission according to risk of developing heterotopic ossification (HO).

SUMMARY OF BACKGROUND DATA

HO in burns is an uncommon but severely debilitating problem with a poorly understood mechanism and no fully effective prophylactic measures.

METHODS

Data were obtained from the Burn Model System National Database from 1994 to 2010 (n = 3693). The primary outcome is diagnosis of HO at hospital discharge. Logistic regression analysis was used to determine significant demographic and medical predictors of HO. A risk scoring system was created in which point values were assigned to predictive factors and final risk score is correlated with the percent risk of developing HO. The model was internally and externally validated.

RESULTS

The mean age of the subjects is 42.5 ± 16.0 years, the mean total body surface area (TBSA) burned is 18.5 ± 16.4%, and the population is 74.9% male. TBSA and the need for grafting of the arm, head/neck, and trunk were significant predictors of HO development (P < 0.01). A 13-point risk scoring system was developed using these significant predictors. The model c-statistic is 0.92. The risk scoring system demonstrated evidence of internal and external validity. An online calculator was developed to facilitate translation of knowledge to practice and research.

CONCLUSIONS

This HO risk scoring system identifies high-risk burn patients suitable for diagnostic testing and interventional HO prophylaxis trials.

Evaluation of Salivary Cytokines for Diagnosis of both Trauma-Induced and Genetic Heterotopic Ossification

PURPOSE

Heterotopic ossification (HO) occurs in the setting of persistent systemic inflammation. The identification of reliable biomarkers can serve as an early diagnostic tool for HO, especially given the current lack of effective treatment strategies. Although serum biomarkers have great utility, they can be inappropriate or ineffective in traumatic acute injuries and in patients with fibrodysplasia ossificans progressiva (FOP). Therefore, the goal of this study is to profile the cytokines associated with HO using a different non-invasive source of biomarkers.

METHODS

Serum and saliva were collected from a model of trauma-induced HO (tHO) with hind limb Achilles' tenotomy and dorsal burn injury at indicated time points (pre-injury, 48 h, 1 week, and 3 weeks post-injury) and a genetic non-trauma HO model (Nfatc1-Cre/caAcvr1fl/wt ). Samples were analyzed for 27 cytokines using the Bio-Plex assay. Histologic evaluation was performed in Nfatc1-Cre/caAcvr1fl/wt mice and at 48 h and 1 week post-injury in burn tenotomy mice. The mRNA expression levels of these cytokines at the tenotomy site were also quantified with quantitative real-time PCR. Pearson correlation coefficient was assessed between saliva and serum.

RESULTS

Levels of TNF-α and IL-1β peaked at 48 h and 1 week post-injury in the burn/tenotomy cohort, and these values were significantly higher when compared with both uninjured (p < 0.01, p < 0.03) and burn-only mice (p < 0.01, p < 0.01). Immunofluorescence staining confirmed enhanced expression of IL-1β, TNF-α, and MCP-1 at the tenotomy site 48 h after injury. Monocyte chemoattractant protein-1 (MCP-1) and VEGF was detected in saliva showing elevated levels at 1 week post-injury in our tHO model when compared with both uninjured (p < 0.001, p < 0.01) and burn-only mice (p < 0.005, p < 0.01). The Pearson correlation between serum MCP-1 and salivary MCP-1 was statistically significant (r = 0.9686, p < 0.001) Similarly, the Pearson correlation between serum VEGF and salivary VEGF was statistically significant (r = 0.9709, p < 0.05).

CONCLUSION

In this preliminary study, we characterized the diagnostic potential of specific salivary cytokines that may serve as biomarkers for an early-stage diagnosis of HO. This study identified two candidate biomarkers for further study and suggests a novel method for diagnosis in the context of current difficult diagnosis and risks of current diagnostic methods in certain patients.

Heterotopic Ossification in adults following a burn: A phenomenological analysis

Heterotopic Ossification (HO) is a rare but severely debilitating complication after a burn. Despite there being literature of varying quality explaining the postulated pathological process, risk factors and treatment for HO, the individual experiences of adults diagnosed with HO following a burn, remains unreported. This study sought to explore and describe burn survivors' experiences of HO to gain a greater understanding of the clinical needs for this unique patient population. A phenomenological inquiry of five men and one woman selected through purposeful sampling collected in-depth interviews analysed using Colaizzi's method of data analysis. Five emergent themes: (1) Early signs and symptoms, (2) Impact on the rehabilitation journey, (3) The role of the health care professionals (4) Loss of independence and an increased reliance on others and, (5) Learning to live with it: uncertainty, hope and adaptation. Eleven cluster themes were identified, highlighting the meaning of each emergent theme. These findings describe the significant impact the unique symptomology of HO had on the physical and psychosocial functioning of participants throughout the rehabilitation journey. Central to engagement in rehabilitation, is the participants' desire for autonomy particularly in the domains of living independently and community re-integration.

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.

Bilateral Scapulohumeral Ankylosis after Prolonged Mechanical Ventilation

This case demonstrates a rarely reported bilateral scapulohumeral bony ankylosis. A young woman developed extensive heterotopic ossifications (HOs) in both shoulder joints after being mechanically ventilated for several months at the intensive care unit in a comatose status. She presented with a severe movement restriction of both shoulder joints. Surgical resection of the bony bridges was performed in 2 separate sessions with a significant improvement of shoulder function afterwards. No postoperative complications, pain, or recurrence of HOs were noted at 1-year follow-up. Mechanical ventilation, immobilization, neuromuscular blockage, and prolonged sedation are known risk factors for the development of HOs in the shoulder joints. Relatively early surgical resection of the HOs can be performed safely in contrary to earlier belief. Afterwards, nonsteroidal anti-inflammatory drugs and/or radiation therapy can be possible treatment modalities to prevent recurrence of HOs.

The posttraumatic stiff elbow: an update

Posttraumatic elbow stiffness is a disabling condition that remains challenging to treat despite improvement of our understanding of the pathogenesis of posttraumatic contractures and new treatment regimens. This review provides an update and overview of the etiology of posttraumatic elbow stiffness, its classification, evaluation, nonoperative and operative treatment, and postoperative management.

Analysis of Bone-Cartilage-Stromal Progenitor Populations in Trauma Induced and Genetic Models of Heterotopic Ossification

Heterotopic ossification (HO), the formation of extra-skeletal bone in soft tissues, is a pathologic process occurring after substantial burns or trauma, or in patients with type I bone morphogenetic protein (BMP) receptor hyperactivating mutations. Identifying the cells responsible for de novo bone formation during adulthood is of critical importance for therapeutic and regenerative purposes. Using a model of trauma-induced HO with hind limb Achilles' tenotomy and dorsal burn injury and a genetic nontrauma HO model (Nfatc1-Cre/caAcvr1(fl/wt) ), we demonstrate enrichment of previously defined bone-cartilage-stromal progenitor cells (BCSP: AlphaV+/CD105+/Tie2-/CD45-/Thy1-/6C3-) at the site of HO formation when compared with marrow isolated from the ipsilateral hind limb, or from tissue of the contralateral, uninjured hind limb. Upon transplantation into tenotomy sites soon after injury, BCSPs isolated from neonatal mice or developing HO incorporate into the developing lesion in cartilage and bone and express chondrogenic and osteogenic transcription factors. Additionally, BCSPs isolated from developing HO similarly incorporate into new HO lesions upon transplantation. Finally, adventitial cells, but not pericytes, appear to play a supportive role in HO formation. Our findings indicate that BCSPs contribute to de novo bone formation during adulthood and may hold substantial regenerative potential. Stem Cells 2016;34:1692-1701.

Treatment of heterotopic ossification through remote ATP hydrolysis

Heterotopic ossification (HO) is the pathologic development of ectopic bone in soft tissues because of a local or systemic inflammatory insult, such as burn injury or trauma. In HO, mesenchymal stem cells (MSCs) are inappropriately activated to undergo osteogenic differentiation. Through the correlation of in vitro assays and in vivo studies (dorsal scald burn with Achilles tenotomy), we have shown that burn injury enhances the osteogenic potential of MSCs and causes ectopic endochondral heterotopic bone formation and functional contractures through bone morphogenetic protein-mediated canonical SMAD signaling. We further demonstrated a prevention strategy for HO through adenosine triphosphate (ATP) hydrolysis at the burn site using apyrase. Burn site apyrase treatment decreased ATP, increased adenosine 3',5'-monophosphate, and decreased phosphorylation of SMAD1/5/8 in MSCs in vitro. This ATP hydrolysis also decreased HO formation and mitigated functional impairment in vivo. Similarly, selective inhibition of SMAD1/5/8 phosphorylation with LDN-193189 decreased HO formation and increased range of motion at the injury site in our burn model in vivo. Our results suggest that burn injury-exacerbated HO formation can be treated through therapeutics that target burn site ATP hydrolysis and modulation of SMAD1/5/8 phosphorylation.

Trauma-induced heterotopic bone formation and the role of the immune system: A review

Extremity trauma, spinal cord injuries, head injuries, and burn injuries place patients at high risk of pathologic extraskeletal bone formation. This heterotopic bone causes severe pain, deformities, and joint contractures. The immune system has been increasingly implicated in this debilitating condition. This review summarizes the various roles immune cells and inflammation play in the formation of ectopic bone and highlights potential areas of future investigation and treatment. Cell types in both the innate and adaptive immune system such as neutrophils, macrophages, mast cells, B cells, and T cells have all been implicated as having a role in ectopic bone formation through various mechanisms. Many of these cell types are promising areas of therapeutic investigation for potential treatment. The immune system has also been known to also influence osteoclastogenesis, which is heavily involved in ectopic bone formation. Chronic inflammation is also known to have an inhibitory role in the formation of ectopic bone, whereas acute inflammation is necessary for ectopic bone formation.

Fibrocytes participate in the development of heterotopic ossification

Heterotopic ossification (HO) is a complication of musculoskeletal injury characterized by the formation of mature bone in soft tissues. The etiology of HO is unknown. We investigated the role of bone marrow derived progenitor cells in HO pathophysiology. We isolated the cells from HO specimens by cell explantation. Using flow cytometry and immunofluorescence microscopy, we found that 35 to 65% of the HO cells exhibit a bone marrow derived fibrocyte profile consisting in spindle-shaped morphology associated with type 1 pro-collagen and LSP1 expression. When cultured in osteogenic differentiation medium, active machinery for bone mineralization (high gene expression of Anx2, TNAP, and Pit-1), and calcium/phosphate deposits were found. Interestingly, interferon-alpha 2b significantly reduced the proliferation rate and COL1 gene expression in HO cells. We have characterized a novel subset of bone marrow derived progenitor cells in the HO specimens. The findings from this research study will provide new insights into the development of HO in burn patients.

Nanogel-Mediated RNAi Against Runx2 and Osx Inhibits Osteogenic Differentiation in Constitutively Active BMPR1A Osteoblasts

Trauma-induced heterotopic ossification (HO) and fibrodysplasia ossificans progressiva (FOP) are acquired and genetic variants of pathological bone formation occurring in soft tissues. Conventional treatment modalities target the inflammatory processes preceding bone formation. We investigated the development of a prophylaxis for heterotopic bone formation by addressing the biological basis for HO - dysregulation in the bone morphogenetic protein (BMP) signaling pathway. We previously reported the synthesis of cationic nanogel nanostructured polymers (NSPs) for efficient delivery of short interfering ribonucleic acids (siRNAs) and targeted gene silencing. Results suggested that nanogel:siRNA weight ratios of 1:1 and 5:1 silenced Runx2 and Osx gene expression in primary mouse osteoblasts with a constitutively active (ca) BMP Receptor 1A (BMPR1A) by the Q233D mutation. Repeated RNAi treatments over 14 days significantly inhibited alkaline phosphatase activity in caBMPR1A osteoblasts. Hydroxyapatite (HA) deposition was diminished over 28 days in culture, though complete suppression of HA deposition was not achieved. Outcome data suggested minimal cytotoxicity of nanogel-based RNAi therapeutics, and the multistage disruption of BMP-induced bone formation processes. This RNAi based approach to impeding osteoblastic differentiation and subsequent bone formation may form the basis of a clinical therapy for heterotopic bone formation.

An expanded delivery model for outpatient burn rehabilitation

Despite the numerous multidisciplinary services burn centers provide, a number of challenges to obtaining optimal outcomes exist. The goal of this study was to overcome the barriers to effective burn rehabilitation by utilizing an expanded care coordinator (ECC) to supplement the existing outpatient services. In this between-group, single-blind, randomized, controlled trial, the control group (n = 41) received standard outpatient care and the experimental group (n = 40) received additional services provided by the ECC, including telephone calls at set intervals (24 hours postdischarge, 2, 4, 8, 12 weeks postdischarge and 5, 7, 9 months postdischarge). The ECC was trained in motivational interviewing, crisis intervention, and solution-focused counseling. He assisted patients before and after each clinic visit, coordinated outpatient services in their geographic area (physical and occupational therapy, counseling, primary care provider referrals, etc.), and helped develop problem-solving approaches to accomplish individualized goals. Outcome measures included patient identified goals utilizing the goal attainment scale, the urn-specific health scale-brief, the Short Form 12, a patient satisfaction survey, and a return to work survey. The average subject age was 43 years (SD = 16.9) with a mean TBSA of 19% (SD = 18.8). The average length of hospitalization was 36 days (SD = 42.9). The patient and injury characteristics were similar between the study groups. For the experimental group, 33% completed seven calls, with 23% completing all the eight calls. All were assessed using general linear models and were adjusted for sex, age, length of hospitalization, urban vs rural area of residence, %TBSA burn, and ethnicity. There was no difference between the control and experimental groups for any of the outcome measures at either 6 or 12 months postburn. No differences in outcomes between the groups were found. All participants appreciated the individualized goal setting process that was used as an outcome measure and this may have accounted for the similar outcomes in both the groups. (The measure may have been more of an intervention, thus contributing to the strength of the control group.) Although most patients with burn injuries may not need an intervention that is this intensive, a subset of patients at higher risk or with more severe injuries may benefit from more intensive and personalized services. Future research should examine the benefits of individual goal setting processes for all the patients and also attempt to identify those patients most at risk for poorer outcomes and therefore, likely to benefit of more intensive personalized services.

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.

What Risk Factors Predict Recurrence of Heterotopic Ossification After Excision in Combat-related Amputations?

BACKGROUND

Heterotopic ossification (HO) is common after combat-related amputations and surgical excision remains the only definitive treatment for persistently symptomatic HO. There is no consensus in the literature regarding the timing of surgery, and recurrence frequency, reexcision, and complications have not been reported in large numbers of patients.

QUESTIONS/PURPOSES

(1) What are the rates of symptomatic recurrence resulting in reexcision and other complications resulting in reoperation in patients with HO? (2) Is either radiographic or symptomatic recurrence dependent on timing and type of initial surgery, the experience of the surgeon in performing the procedure, the severity of preexcision HO, the presence of concomitant neurologic injury, or the use of postoperative HO prophylaxis?

METHODS

Between March 2005 and March 2013 our institution treated 994 patients with 1377 combat-related major extremity amputations; of those, 172 amputations underwent subsequent excision of symptomatic HO. The mechanism of injury resulting in nearly all amputations (n = 168) was blast-related trauma. We reviewed medical records and radiographs to collect initial grade of HO, radiographic recurrence, complete compared with partial excision, concomitant neurologic injury, timing to initial surgery, surgeon experience, and use of postexcision prophylaxis with our primary study outcome being a return to the operating room (OR) for repeat excision of symptomatic HO. All 172 combat-related amputations were considered for this study irrespective of followup, which was noted to be robust, with 157 (91%) amputations having at least 6 months clinical followup by an orthopaedic surgeon or physiatrist (median, 20 months; range, 0-88 months).

RESULTS

Eleven of 172 patients (6.5%) underwent reexcision of HO, and 67 complications resulting in return to the OR occurred in 53 patients (31%) of patients. Multivariate analysis of our primary outcome measure showed more frequent symptomatic recurrences requiring reexcision when initial excision was performed as a partial excision (p = 0.03; odds ratio [OR], 5.0; 95% confidence interval [CI], 1.2-29.6) or when the initial excision was performed within 180 days of injury (p = 0.047; OR, 4.1; 95% CI, 1.02-16.6). There was no association between symptomatic recurrence and HO grade, central nervous system injury, experience of the attending surgeon, or postoperative prophylaxis. Radiographic recurrence was observed when partial excisions (eight of 30 [27%]) were done compared with complete excisions (five of 77 [7%]; p = 0.008).

CONCLUSIONS

HO is common after combat-related amputations, and patients undergoing surgical excision of HO for this indication often have complications that result in repeat surgical procedures. Partial excisions of immature lesions more often resulted in both symptomatic and radiographic recurrence. The likelihood of a patient undergoing reexcision can be minimized by performing a complete excision at least 180 days from injury to surgery with no evidence of a reduced risk of reexcision by waiting longer than 270 days.

LEVEL OF EVIDENCE

Level III, therapeutic study.

The time point in surgical excision of heterotopic ossification of post-traumatic stiff elbow: recommendation for early excision followed by early exercise

BACKGROUND

Post-traumatic heterotopic ossification (HO) around the elbow may severely impair joint function. Although surgical excision is effective at restoring range of motion (ROM), traditional surgical treatment is postponed for at least 1 year to prevent recurrence, which leads to secondary contracture of the elbow. Because the optimal timing of resection is controversial, our study was performed to compare recurrence and elbow function between early and late excision in our patients to determine whether the delay is necessary.

METHODS

We retrospectively reviewed 164 patients during a 4-year period. In the control group (112 patients), HO was excised at an average of 23.0 months after initial injury (range, 9-204 months); in the early excision group (52 patients), resection was performed at an average of 6.1 months (range, 3-8 months). HO recurrence was assessed by the Hastings classification system. Final ROM and Mayo Elbow Performance Scores were also evaluated.

RESULTS

Recurrent HO was observed in 30 of 112 patients (26.8%) in the control group and 15 of 52 (28.9%) in early excision group. No significant difference in HO recurrence was found between the 2 groups (P = .942). Moreover, there were no notable differences regarding ROM, Mayo Elbow Performance Scores, and complications postoperatively.

CONCLUSIONS

Early excision associated with early exercise is effective for the treatment of HO aiming at a low recurrence rate and satisfactory function. The conventional surgical delay of more than 1 year may be shortened.

Effects of blockade of endogenous Gi signaling in Tie2-expressing cells on bone formation in a mouse model of heterotopic ossification

Available evidence indicates that some Tie2-expressing (Tie2(+) ) cells serve as multipotent progenitors that have robust BMP-dependent osteogenic activity and mediate heterotopic ossification (HO). Since signaling through the G protein Gi is required for cell motility, we hypothesized that blockade of endogenous Gi signaling in Tie2(+) cell populations would prevent HO formation. Blockade of Gi signaling in Tie2(+) cells was accomplished in transgenic mice with expression of pertussis toxin (PTX) under the control of the Tie2 promoter (Tie2(+) /PTX(+) ). Bone formation within HOs was evaluated 2 weeks after BMP injection. Expression of PTX in Tie2(+) cells significantly reduced the bone volume (BV) of HOs in male and female mice. Orthotopic bones were assessed at the distal femur and expression of PTX significantly increased trabecular bone fractional volume and bone formation rate in females only. In adult Tie2(+) /GFP(+) mice, GFP(+) cells appeared both inside and at the surfaces of bone tissue within HOs and in orthotopic bones. In summary, blockade of Gi signaling in Tie2(+) cells reduced the accrual of HOs and stimulated osteogenesis in orthotopic bones. Targeting of Gi protein coupled receptors in Tie2(+) cells may be a novel therapeutic strategy in states of abnormal bone formation such as osteoporosis and 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.

Cationic Nanogel-mediated Runx2 and Osterix siRNA Delivery Decreases Mineralization in MC3T3 Cells

BACKGROUND

Heterotopic ossification (HO) may occur after musculoskeletal trauma, traumatic brain injury, and total joint arthroplasty. As such, HO is a compelling clinical concern in both military and civilian medicine. A possible etiology of HO involves dysregulated signals in the bone morphogenetic protein osteogenic cascade. Contemporary treatment options for HO (ie, nonsteroidal antiinflammatory drugs and radiation therapy) have adverse effects associated with their use and are not biologically engineered to abrogate the molecular mechanisms that govern osteogenic differentiation.

QUESTIONS/PURPOSES

We hypothesized that (1) nanogel-mediated short interfering RNA (siRNA) delivery against Runt-related transcription factor 2 (Runx2) and osterix (Osx) genes will decrease messenger RNA expression; (2) inhibit activity of the osteogenic marker alkaline phosphatase (ALP); and (3) inhibit hydroxyapatite (HA) deposition in osteoblast cell cultures.

METHODS

Nanogel nanostructured polymers delivered siRNA in 48-hour treatment cycles against master osteogenic regulators, Runx2 and Osx, in murine calvarial preosteoblasts (MC3T3-E1.4) stimulated for osteogenic differentiation by recombinant human bone morphogenetic protein (rhBMP-2). The efficacy of RNA interference (RNAi) therapeutics was determined by quantitation of messenger RNA knockdown (by quantitative reverse transcription-polymerase chain reaction), downstream protein knockdown (determined ALP enzymatic activity assay), and HA deposition (determined by OsteoImage™ assay).

RESULTS

Gene expression assays demonstrated that nanogel-based RNAi treatments at 1:1 and 5:1 nanogel:short interfering RNA weight ratios reduced Runx2 expression by 48.59% ± 19.53% (p < 0.001) and 43.22% ± 18.01% (both p < 0.001). The same 1:1 and 5:1 treatments against both Runx2 and Osx reduced expression of Osx by 51.65% ± 10.85% and 47.65% ± 9.80% (both p < 0.001). Moreover, repeated 48-hour RNAi treatment cycles against Runx2 and Osx rhBMP-2 administration reduced ALP activity after 4 and 7 days. ALP reductions after 4 days in culture by nanogel 5:1 and 10:1 RNAi treatments were 32.4% ± 12.0% and 33.6% ± 13.8% (both p < 0.001). After 7 days in culture, nanogel 1:1 and 5:1 RNAi treatments produced 35.9% ± 14.0% and 47.7% ± 3.2% reductions in ALP activity. Osteoblast mineralization data after 21 days suggested that nanogel 1:1, 5:1, and 10:1 RNAi treatments decreased mineralization (ie, HA deposition) from cultures treated only with rhBMP-2 (p < 0.001). However, despite RNAi attack on Runx2 and Osx, HA deposition levels remained greater than non-rhBMP-2-treated cell cultures.

CONCLUSIONS

Although mRNA and protein knockdown were confirmed as a result of RNAi treatments against Runx2 and Osx, complete elimination of mineralization processes was not achieved. RNAi targeting mid- and late-stage osteoblast differentiation markers such as ALP, osteocalcin, osteopontin, and bone sialoprotein) may produce the desired RNAi-nanogel nanostructured polymer HO prophylaxis.

CLINICAL RELEVANCE

Successful HO prophylaxis should target and silence osteogenic markers critical for heterotopic bone formation processes. The identification of such markers, beyond RUNX2 and OSX, may enhance the effectiveness of RNAi prophylaxes for HO.

The development of a rat model to investigate the formation of blast-related post-traumatic heterotopic ossification

Currently, there is no animal model in which to evaluate the underlying physiological processes leading to the heterotopic ossification (HO) which forms in most combat-related and blast wounds. We sought to reproduce the ossification that forms under these circumstances in a rat by emulating patterns of injury seen in patients with severe injuries resulting from blasts. We investigated whether exposure to blast overpressure increased the prevalence of HO after transfemoral amputation performed within the zone of injury. We exposed rats to a blast overpressure alone (BOP-CTL), crush injury and femoral fracture followed by amputation through the zone of injury (AMP-CTL) or a combination of these (BOP-AMP). The presence of HO was evaluated using radiographs, micro-CT and histology. HO developed in none of nine BOP-CTL, six of nine AMP-CTL, and in all 20 BOP-AMP rats. Exposure to blast overpressure increased the prevalence of HO.

This model may thus be used to elucidate cellular and molecular pathways of HO, the effect of varying intensities of blast overpressure, and to evaluate new means of prophylaxis and treatment of heterotopic ossification.

Cite this article: Bone Joint J 2015;97-B:572–6

Physical and psychiatric recovery from burns

Burn injuries pose complex biopsychosocial challenges to recovery and improved comprehensive care. The physical and emotional sequelae of burns differ, depending on burn severity, individual resilience, and stage of development when they occur. Most burn survivors are resilient and recover, whereas some are more vulnerable and have complicated outcomes. Physical rehabilitation is affected by orthopedic, neurologic, and metabolic complications and disabilities. Psychiatric recovery is affected by pain, mental disorders, substance abuse, and burn stigmatization. Individual resilience, social supports, and educational or occupational achievements affect outcomes.

Characterization of heterotopic ossification in burn patients

Heterotopic ossification (HO) is a clinical condition of ectopic bone formation in soft tissue. This clinical entity has been associated with genetic disorders, traumatic injuries, and musculoskeletal surgeries. In this regard, functional impairments secondary to scar contractures seen in burn injuries may be exacerbated with underlying HO. The appropriate prevention or management of this complication is crucial to optimize outcome in burn patients. This clinical study reviews the incidence of HO in our burned patients, diagnostic methods, therapeutic approaches including surgical timing and techniques.

Physical and psychiatric recovery from burns

Burn injuries pose complex biopsychosocial challenges to recovery and improved comprehensive care. The physical and emotional sequelae of burns differ, depending on burn severity, individual resilience, and stage of development when they occur. Most burn survivors are resilient and recover, whereas some are more vulnerable and have complicated outcomes. Physical rehabilitation is affected by orthopedic, neurologic, and metabolic complications and disabilities. Psychiatric recovery is affected by pain, mental disorders, substance abuse, and burn stigmatization. Individual resilience, social supports, and educational or occupational achievements affect outcomes.

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.