Cost of Radiotherapy Versus NSAID Administration for Prevention of Heterotopic Ossification After Total Hip Arthroplasty

Eficácia do ibuprofeno após artroplastia total de quadril para prevenção de ossificação heterotópica: Revisão sistemática e meta-análise

O objetivo deste estudo foi realizar uma revisão sistemática e meta-análise de estudos clínicos randomizados (ECRs) relevantes para determinar o papel do ibuprofeno, sua dose ideal, e a duração do tratamento na prevenção de ossificação heterotópica (OH) após a artroplastia total primária do quadril (ATQ). Uma pesquisa bibliográfica foi feita nos bancos de dados PubMed/MEDLINE e Cochrane Library para a obtenção de ECRs que comparassem o uso de ibuprofeno e de placebo como profilaxia para OH em pacientes submetidos à ATQ. Os principais desfechos deste estudo foram ocorrência geral de OH, classificação de Brooker da OH, e complicações gastrintestinais. No total, 27 artigos foram identificados nos bancos de dados e 4 estudos, com 1.153 pacientes, foram incluídos na análise final. Em comparação ao placebo, o uso de ibuprofeno reduziu a incidência de OH aos 3 e 12 meses de acompanhamento e a incidência de OH Brooker II e III (p < 0,05). No entanto, não houve diferença significativa entre os grupos que receberam ibuprofeno e placebo em termos de interrupção do tratamento devido a complicações gastrintestinais ou da incidência de OH Brooker I e IV (p > 0,05). Os dados existentes indicam que o ibuprofeno é seguro e eficaz na redução da incidência total de OH e de OH Brooker II e III durante o acompanhamento. No entanto, as conclusões são limitadas devido ao pequeno número de estudos; logo, mais estudos clínicos de alta qualidade são necessários para o desenvolvimento de diretrizes em relação à dose e duração ideal da terapia.

Comparative proteomic analysis identifies differentially expressed proteins and reveals potential mechanisms of traumatic heterotopic ossification progression

Background

Traumatic Heterotopic Ossification (tHO) is one of complications of elbow fractures to the detriment of patients' rehabilitation, and the severity of tHO corresponds to the size of ectopic bone. It has yet to be elucidated which proteins and pathways underlying the progression of tHO, and biomarkers to predict the severity of tHO at early stage of the disease also need further investigation.

Methods

In this study, a new rat model with distinct volume of ectopic bone was established first. Then a data-independent acquisition proteomics approach was used to investigate injured site tissues sequentially obtained from these rats (2, 7, 14, and 28 days post-injury). Differentially expressed analysis, functional annotation and co-expression analysis and protein-protein interaction network were performed to explore the pathways and hub proteins in the tHO progression. Clinical samples from a nest case-control study were used to validate the selected proteins for predicting the severity of tHO.

Results

The Achilles Tenotomy (AT) induced significantly larger sizes of ectopic bone compared to Partial Achilles Tenotomy (PAT) in rat models. A total of 3547 quantifiable proteins were screened for differential expression analysis among the AT, PAT and control groups. The hierarchical clustering and expression pattern analysis revealed more apparent difference in the pathways such as oxidative phosphorylation, mitochondrial function, and sirtuin signaling between AT and PAT group at the early stage (2 dpi) of tHO. The co-expression analysis identified five hub proteins, UBA1, EIF3E, RPL17, RPL27, and RPS28. qPCR assay, immunoblot assay and immunohistochemistry assay verified that these proteins had higher expression level in the tissue samples of clinically relevant HO patients and clinically irrelevant HO patients than HO negative patients.

Conclusion

The new established animal model and proteome profile could serve as a solid foundation for the comprehensive investigation of the progression of traumatic heterotopic ossification. And the identified 5 proteins (UBA1, EIF3E, RPL17, RPL27, and RPS28) may serve as potential biomarkers to predict the severity of tHO.

The translational potential of this article

The proteins identified in this study may be the potential biomarkers and therapeutic targets for predicting and treating the tHO at early stage.

Diclofenac for prophylaxis of heterotopic ossification after hip arthroplasty: a systematic review

BACKGROUND

Heterotopic ossification (HO) is defined as the formation of lamellar bone in extraskeletal soft tissues. HO can be a severe complication after hip arthroplasty but can possibly be prevented by postoperative treatment with non-steroidal anti-inflammatory drugs (NSAIDs) or radiotherapy. Diclofenac is 1 of the most used drugs in HO prophylaxis because it is effective and long established. However, there is still no uniform therapy regimen in terms of duration, dose and side effect profile regarding the application of diclofenac in HO prevention. We have, therefore, conducted the first systematic review investigating diclofenac for HO prophylaxis after hip arthroplasty. The aim of this study is to assess the efficacy, dose and duration of diclofenac therapy in preventing HO after total hip arthroplasty (THA).

METHODS

According to the PRISMA Guidelines we performed a systematic literature search in EMBASE via Ovid, in MEDLINE via PubMed and in the Cochrane Library addressing all studies in English and German regarding the prophylaxis of HO with diclofenac after THA. We identified 731 potential studies and included 6 randomised controlled trials with 957 patients.

RESULTS

The studies were heterogeneous with regard to duration of therapy, dose, comparative group and follow-up period. The therapy duration ranged from 9 to 42 days, the applied diclofenac doses ranged from 75 mg to 150 mg daily. Patients treated with diclofenac showed a significant reduction in the total incidence of HO regarding to the Brooker Classification compared to placebo and no clinically relevant ossifications occured (Brooker III and IV).

CONCLUSIONS

Diclofenac is efficacious in the prevention of HO and can be used routinely after THA. The existing data indicates that a minimum dose of 75 mg diclofenac per day started on the first postoperative day for a minimum of 9 days is needed to prevent HO with an acceptable incidence of side effects, such as gastrointestinal symptoms.

Radiation-Induced Sarcoma After Heterotopic Ossification Prophylaxis: A Case Report

CASE

Heterotopic ossification (HO) is a pathological formation of bone in nonosseous tissue and is a common complication of orthopaedic procedures. Radiotherapy is often used to prevent HO despite the small risk of secondary malignancy. Here, we report a case of a patient who developed a periprosthetic, radiation-induced sarcoma after delivery of a single fraction of 7 Gy for HO prophylaxis. This sarcoma was found to lie entirely within the treatment field and occurred within 5 years of radiation.

CONCLUSION

Appropriate counseling regarding radiation-induced sarcoma formation should be provided to patients considering radiotherapy for this HO prophylaxis.

Proteomic characterization of a trauma-based rat model of heterotopic ossification identifies interactive signaling networks as potential therapeutic targets

Heterotopic ossification (HO) is the formation of ectopic bone in soft tissues observed in patients following blast injuries, orthopedic or head trauma, burns, or in the context of inborn mutations of genes involved in osteogenesis. There is no universally accepted therapy for HO. This study has used global unbiased mass spectrometry proteomic approaches, validated by western immunoblots, to interrogate skeletal muscle tissues obtained from a highly reproducible rat model of trauma induced HO. During early the phase of HO development, statistically significant modulation of proteins within the following pathways was identified: coagulation, cyclic AMP, extracellular matrix, immunity/inflammation, NADH metabolism, TGFβ. These metabolic proteins and pathways have the potential to serve as diagnostic, prognostic, and therapeutic targets for this devastating orthopedic condition that has considerable impact on the patient's quality of life. Furthermore, the findings confirm and extend previous in vitro stromal/stem cell and clinical studies from the field. SIGNIFICANCE: This study confirms and extends the field's understanding of the protein pathways that are modulated in a rat model of trauma induced heterotopic ossification. The identification of specific proteins such as the AP1 transcription factor as well as protein families such as the complement/coagulation pathway and serine protease inhibitors as biomarkers have potential clinical translational value. These outcomes have relevance to the physiological and pathological mineralization processes contributing to the recovery of orthopedic trauma patients.

The Survey of Cells Responsible for Heterotopic Ossification Development in Skeletal Muscles-Human and Mouse Models

Heterotopic ossification (HO) manifests as bone development in the skeletal muscles and surrounding soft tissues. It can be caused by injury, surgery, or may have a genetic background. In each case, its development might differ, and depending on the age, sex, and patient's conditions, it could lead to a more or a less severe outcome. In the case of the injury or surgery provoked ossification development, it could be, to some extent, prevented by treatments. As far as genetic disorders are concerned, such prevention approaches are highly limited. Many lines of evidence point to the inflammatory process and abnormalities in the bone morphogenetic factor signaling pathway as the molecular and cellular backgrounds for HO development. However, the clear targets allowing the design of treatments preventing or lowering HO have not been identified yet. In this review, we summarize current knowledge on HO types, its symptoms, and possible ways of prevention and treatment. We also describe the molecules and cells in which abnormal function could lead to HO development. We emphasize the studies involving animal models of HO as being of great importance for understanding and future designing of the tools to counteract this pathology.

Heterotopic ossification: radiological and pathological review

Background Heterotopic Ossification (HO) is a common condition referring to ectopic bone formation in soft tissues. It has two major etiologies, acquired (more common) and genetic. The acquired form is closely related to tissue trauma. The exact pathogenesis of this disease remains unclear; however, there is ongoing research in prophylactic and therapeutic treatments that is promising. Conclusions Due to HO potential to cause disability, it is so important to differentiate it from other causes in order to establish the best possible management.

Efficacy of Nonsteroidal Anti-inflammatory Drug Prophylaxis for Heterotrophic Ossification in Hip Arthroscopy: A Systematic Review

PURPOSE

The purpose of this systematic review was to investigate the efficacy of nonsteroidal anti-inflammatory drug (NSAID) prophylaxis for preventing heterotopic ossification (HO) in the setting of hip arthroscopy.

METHODS

A systematic search was performed in duplicate for studies comparing the use of NSAID prophylaxis for HO in the setting of hip arthroscopy until March 2015. Study parameters--including sample size, incidence of HO, adverse effects, and level of symptoms--were obtained. Furthermore, the level of evidence of studies was collected and quality assessment was performed. The difference in incidence as well as pooled odds ratios were calculated and analyzed to compare no prophylaxis versus NSAID prophylaxis.

RESULTS

This systematic review identified 5 studies, consisting of 1,662 patients, investigating NSAID prophylaxis in hip arthroscopy. HO was diagnosed with the use of postoperative hip radiographs at follow-up, with 95% of cases classified using the Brooker classification. The incidence of HO was 13.4% without NSAID prophylaxis and 3.3% with NSAID prophylaxis. Pooled odds ratios from the prospective studies were 0.07 (95% confidence interval [CI], 0.02 to 0.28; P = .0002; I(2) = 0%), showing with statistical significance that NSAID prophylaxis decreased the incidence of HO. The retrospective data similarly showed pooled odds ratios of 0.03 (95% CI, 0.00 to 1.43); P = .08; I(2) = 84%), although it was not statistically significant. Most of the patients who experienced HO in both groups were not reported to be symptomatic. Adverse effects and compliance were not consistently reported.

CONCLUSIONS

The available orthopaedic literature suggests that the incidence of postoperative HO may be decreased with the use of NSAID prophylaxis in hip arthroscopy. However, the evidence is unclear regarding NSAID drug regimen choice, drug compliance, and adverse effects.

LEVEL OF EVIDENCE

Level III, systematic review of Level I, Level II, and Level III studies.

Pathogenesis and prevention strategies of heterotopic ossification in total hip arthroplasty: a narrative literature review and results of a survey in Germany

INTRODUCTION

Heterotopic ossification (HO) after THA can lead to pain, impaired range of motion and possibly revision surgery. This article summarizes current literature on the pathogenesis of HO in THA and trauma. Second, it presents the results of a survey on prophylactic concepts for HO in Germany.

MATERIALS AND METHODS

A narrative literature review was conducted by searching three databases (Pubmed, ScienceDirect, the Cochrane library) on the aetiology of HO. Between 2013 and 2014, a questionnaire was sent to 119 orthopaedic and trauma surgery departments in Germany.

RESULTS

The acquired form of HO seems to develop after tissue trauma, which induces a local inflammation. A change in tissue conditions, multiple signalling pathways and involvement of several different cell types seem to promote enchondral ossification and finally HO formation. The feed back rate of the survey was 67%. Eighty-seven percent of all departments currently administer NSAIDs with a mean time span of 3 weeks after surgery for oral prophylaxis. Prophylactic perioperative irradiation is performed in 64% of trauma/orthopaedic departments if the patient is at risk for HO with a mean dosage of 7 Gy.

CONCLUSIONS

Basic research detected new pathways and cell signalling mechanisms of HO pathogenesis, which could offer new treatment and prophylaxis options in the near future. So far, there is no uniform strategy for the clinical prophylaxis of HO in THA. Guidelines and new clinical trials need to be developed to further reduce HO rates in THA.

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.

The influence of pregnancy on heterotopic ossification post-displaced acetabular fractures surgical repair

Pregnancy is associated with maternal bone mineral density loss and modulation of calcium metabolism. We hypothesized that pregnancy may decrease the risk of heterotopic ossification (HO) after trauma. This is a single-institution, University of Mississippi Medical Center, retrospective study investigating the effect of pregnancy on the incidence HO after surgical repair (SR) of displaced acetabular fractures. Between January 1998 and 2010, 257 non-pregnant women (Group A) and 16 pregnant women (Group B) were identified. All the non-pregnant women received radiation therapy (RT) ± indomethacin. None of the pregnant women in group B received any prophylaxis. After a median follow-up of 6.6 years the incidence of HO in all patients was 27% (75/273). In Group A, non-pregnant, women who received RT ± indomethacin, 29% developed HO; HO risk was 0.4. In Group B, 16 pregnant patients, only one developed HO (6%); HO risk was 0.06. Thus, the risk of HO appears to be nearly six-fold higher in non-pregnant women despite prophylactic RT ± indomethacin. Our data suggest that pregnancy may be associated with a reduced risk of HO after SR of displaced acetabular fractures. Further analysis with a larger pregnant patient sample is necessary to confirm this finding.

Physical therapy and surgery

Physical therapy and orthopedic surgery are important components in the treatment of ankylosing spondylitis (AS). Supervised physical therapy is more effective than individual or unsupervised exercise in improving symptoms, but controlled trials suggest that combined inpatient and outpatient therapy provides the greatest improvement. Recommendations for exercise are universal, but the best types and sequence of therapies are not known. Total hip replacement is the surgery most commonly performed for AS, with good long-term implant survival. Heterotopic ossification may occur no more frequently after hip replacement in patients with AS than in patients with other diseases. Corrective spinal surgery is rarely performed and requires specialized centers and experienced surgeons.

The incidence of heterotopic ossification after hip arthroscopy

BACKGROUND

Minimally invasive techniques to treat femoroacetabular impingement (FAI), snapping hip syndrome, and peritrochanteric space disorder (PSD) were developed to reduce complications and recovery time. Although a multitude of studies have reported on the incidence of heterotopic ossification (HO) after open procedures of the hip, there is little known about the rate of HO after hip arthroscopy.

HYPOTHESES

The incidence of HO after hip arthroscopy is comparable with that after open surgical dislocation of the hip and can be reduced with the addition of indomethacin to an existing nonsteroidal anti-inflammatory medication prophylaxis protocol.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Between July 2008 and July 2010, 616 primary hip arthroscopies were performed to treat FAI and PSD. In July 2009, indomethacin was added in the acute postoperative period to an existing HO prophylactic protocol of naproxen administered for 30 days postoperatively. Postoperative radiographs were reviewed to detect the presence and classify the size and location of HO. Odds ratios and logistic regression explored predictor variables and their relationships with HO, with P < .05 defined as significant.

RESULTS

Twenty-nine (21 male, 8 female) of 616 (4.7%) hip procedures developed HO postoperatively. Brooker classification of HO was 18 grade I, 4 grade II, 6 grade III, and 1 grade IV. Mean follow-up was 13.2 months (range, 2.9-26.5 months). Rate of HO for cases with and without indomethacin for prophylaxis was 1.8% (6/339) and 8.3% (23/277), respectively. This difference was statistically significant (P < .05), and patients who underwent protocol 1 were 4.36 times more likely to develop HO postoperatively than those who had protocol 2. The majority of cases of HO (72.4%) occurred in male patients, and all cases occurred in the setting of osteoplasty performed for symptomatic FAI. We were not able to demonstrate statistically significant clinical risk factors that were predictive for the development of postoperative HO. However, the data clearly demonstrate that the performance of arthroscopic osteoplasty with a capsular cut in male patients represented the majority of cases, who are likely the group at highest risk. Seven cases (~1%) required revision procedures to excise HO. There were no cases of recurrence of HO after excision, whether it was performed open or arthroscopically.

CONCLUSION

The addition of indomethacin is effective in reducing the incidence of HO after hip arthroscopy and should be especially considered in male patients who undergo osteoplasty for correction of symptomatic FAI.

[Heterotopic ossifications in total hip arthroplasty: prophylaxis and therapy]

Heterotopic ossification (HO) is a frequent and occasionally severe complication after total hip arthroplasty. Clinical symptoms of this benign abnormal bone formation are loss of mobility and local pain. The etiology and pathomechanisms are not yet completely understood. Overexpression of bone morphogenetic proteins and dysregulation of prostaglandin metabolism seem to be relevant. Medication with non-steroidal anti-inflammatory drugs (NSAIDs) and perioperative single dose radiotherapy are used for prophylaxis, whereby radiotherapy should only be performed in patients with a history of HO or additionally after resection of HO. From currently available data selective cyclooxygenase-2 inhibitors seem to have a preventive efficacy equal to the classical NSAIDs diclofenac and indometacin. This work discusses current knowledge about the pathophysiology, risk factors and the clinical approach for prevention and treatment of HO.

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.

Heterotopic ossification after patellar tendon repair in a man with trisomy 8 mosaicism: a case report and literature review

INTRODUCTION

Heterotopic ossification is the abnormal formation of lamellar bone in soft tissue. Its presence jeopardizes functional outcome, impairs rehabilitation and increases costs due to subsequent surgical interventions.

CASE PRESENTATION

We present a case of a 32-year-old African-American man with trisomy 8 mosaicism who developed severe heterotopic ossification of his right extensor mechanism subsequent to repair of a patellar tendon rupture.

CONCLUSION

To the best of our knowledge there are no prior reports of heterotopic ossification as a complication of patellar tendon repair. This case may suggest an association between trisomy 8 mosaicism and increased risk of heterotopic ossification.

Economic evaluation of NSAID and radiation to prevent heterotopic ossification after hip surgery

INTRODUCTION

Heterotopic ossification (HO) is a known complication in hip surgery, but there is still uncertainty whether to use non-steroidal anti-inflammatory drugs (NSAID) or radiation in its prevention. While the literature focuses almost exclusively on (as it turns out the lacking) difference in effectiveness, one important difference that has been widely unacknowledged thus far is cost-effectiveness.

METHOD

We systematically reviewed the literature to extract evidence-based estimates of treatment effectiveness, complications, and associated costs. These variables are combined in a decision tree to calculate costs for all potential outcomes and tested in sensitivity analyses. Finally, the incremental cost-effectiveness ratio (ICER) was calculated. Data on the effectiveness of both treatments could be extracted from nine randomized controlled trails and one meta-analysis.

RESULTS

Across the 95% confidence interval for the risk difference of HO despite treatment radiation is either dominated by NSAID, which are cheaper and more effective, or has an ICER of US$ 5,858.93 per additionally prevented case of HO.

CONCLUSION

Among the studied variables that might affect cost-effectiveness, the rate of complications requiring treatment was by far the most influential.

Quality of life and cost-effectiveness 1 year after total hip arthroplasty

Quality of life index (Quality Of Well-Being [QWB]) was used to calculate the costs per quality of well year (QWY) in total hip arthroplasty (THA) and compare it to other interventions. Ninety-eight primary and/or revision THA were reviewed. Patients had minimum 1-year follow-up. Quality of life index was used to calculate the costs per QWY in primary and revision THA. Preoperative QWB for primary THA was 0.52 ± 0.06 SD; revision was 0.53 ± 0.07 SD. The QWB change at 1 year for primary THA was 0.08 ± 0.13 SD; revision THA was 0.06 ± 0.14 SD. Calculated costs per QWY were $5572 for primary procedures and $10,775 for revision procedures. Cost-effectiveness of THA compares favorably with other surgical and medical interventions such as epilepsy ablation surgery and gastric bypass surgery.

Heterotopic ossification revisited

Heterotopic ossification is the abnormal formation of mature lamellar bone within extraskeletal soft tissues where bone does not exist. Heterotopic ossification has been classified into posttraumatic, nontraumatic or neurogenic, and myositis ossificans progressiva or fibrodysplasia ossificans progressive. The pathophysiology is unknown. Anatomically, heterotopic ossification occurs outside the joint capsule without disrupting it. The new bone can be contiguous with the skeleton but generally does not involve the periosteum. Three-phase technetium-99m (99mTc) methylene diphosphonate bone scan is the most sensitive imaging modality for early detection and assessing the maturity of heterotopic ossification. Nonsurgical treatment with indomethacin and radiation therapy is appropriate for prophylaxis or early treatment of heterotopic ossification. Although bisphosphonates are effective prophylaxis if initiated shortly after the trauma, mineralization of the bone matrix resumes after drug discontinuation. During the acute inflammatory stage, the patient should rest the involved joint in a functional position; once acute inflammatory signs subside, passive range of motion exercises and continued mobilization are indicated. Surgical indications for excision of heterotopic ossification include improvement of function, standing posture, sitting or ambulation, independent dressing, feeding and hygiene, and repeated pressure sores from underlying bone mass. The optimal timing of surgery has been suggested to be a delay of 12 to 18 months until radiographic evidence of heterotopic ossification maturation and maximal recovery after neurological injury. The ideal candidate for surgical treatment before 18 months should have no joint pain or swelling, a normal alkaline phosphatase level, and 3-phase bone scan indicating mature heterotopic ossification.

Prophylaxis of heterotopic ossification of the hip: systematic review and meta-analysis

Heterotopic ossification (HO) is a potentially severe, if infrequent, complication in hip surgery, and uncertainty exists regarding whether to use NSAIDs or radiation in its prevention. Thus, we systematically reviewed the literature in MedLine, EMBASE, CINAHL, and the Cochrane Controlled Trial Register and, after ruling out publication bias and data heterogeneity, performed a meta-analysis of randomized, controlled trials to assess effectiveness and complications of NSAIDs and radiation in the prevention of HO. We identified nine studies reporting on effectiveness and complications including a total of 1295 patients. The pooled risk ratio for the effectiveness in HO prevention was 0.96 (95% confidence interval, 0.88-1.06) and was independent of the type of surgery (THA or open reduction and internal fixation). There was no association with gender, age, length of followup, or year of publication. The risk ratio for associated complications was 0.79 (95% confidence interval, 0.45-1.41), and, again, was independent of the aforementioned factors. We found no evidence for a statistically significant or clinically important difference between NSAIDs or radiation in preventing HO.

Prophylaxis of heterotopic ossification - an updated review

Heterotopic ossification (HO) is defined as the process by which trabecular bone forms outside of the skeletal structure, occupying space in soft tissue where it does not normally exist. The current popular prophylactic treatment modalities include non-steroidal anti-inflammatory drugs (NSAIDs) and radiation therapy, although the literature remains inconclusive as to which is superior. Additionally, both treatments can lead to adverse effects to the patient. Recently there have been several studies attempting to identify new aspects of the etiology of heterotopic bone formation and introduce new prophylactic modalities with increased efficacy and fewer side effects. For this review, we selectively retrieved articles from Medline published from 1958–2008 on the prophylaxis of HO with the aim of assisting readers in quickly grasping the current status of research and clinical aspects of HO prophylaxis.