Prevention of heterotopic ossification in high-risk patients with total hip arthroplasty: the experience of a combined therapeutic protocol

Severe heterotopic ossification after total hip arthroplasty in male patients under 70 years of age: effectiveness of prophylactic protocol

BACKGROUND

This study aims to evaluate the incidence of clinically significant heterotopic ossification (HO) in primary total hip arthroplasty (THA), comparing outcomes with and without the adoption of an HO prophylactic protocol in male patients under 70 years of age.

METHODS

The prophylactic protocol involved the administration of 50 mg of Indomethacin twice daily for 3 weeks. HO presence was classified according to the Brooker classification system, considering "severe" clinically significant HO (Brooker grade 3 and 4).

RESULTS

Two hundred and seventy-nine patients were included in our study, and an overall HO rate of 68.2% versus a rate of 61.5% was found respectively in patients not subjected and subjected to prophylactic protocol, without significant difference (PR 0.062). However, patients not subjected to the HO prophylactic protocol exhibited a severe HO rate of 22.4% compared to 7.7% in the prophylactic group, with a statistically significant difference (P = 0.008).

CONCLUSIONS

Our study demonstrated that prophylactic protocol adoption is significantly associated with lower rate of severe HO in male patients under 70 years of age. Currently, there are no orthopedic guidelines for the prevention and management of HO after THA, but in the absence of contraindications, the adoption of a prophylactic protocol for HO should always be considered in high-risk patients.

"Heterotopic ossification after total hip arthroplasty through direct anterior approach without a dedicated orthopaedic table or direct lateral approach: a quasi-randomized single-center study"

INTRODUCTION

Heterotopic ossifications (HO) are common after total hip arthroplasty (THA). The invasiveness of surgical approaches plays a relevant role in HO development. The aims of this study were to assess the development of HO 6 months after THA through direct lateral approach (DLA) or direct anterior approach (DAA) without a dedicated orthopaedic table and to assess the clinical impact of HO.

METHODS

This is a single-center IRB-approved, quasi-randomized prospective cohort, observational imaging study. Fifty patients underwent primary THA through DLA and 50 through DAA. Age, sex, BMI and side of the affected hip were collected. At the 6 post-operative month the Harris Hip Score (HHS) and the presence of HO (scored through the Brooker classification system) were assessed.

RESULTS

There was no significant difference in the demographic data between groups. Operative time was significantly higher in the DAA group (72 ± 10 min vs. 58 ± 8 min: p < 0.03). At 6 post-operative months the incidence of HO was 14% in the DAA group and 32% in the DLA group (p = 0.02). Severe HO (Brooker 3-4) were significantly more common in the DLA group (p = 0.04). There was no significant difference in the HHS of patients with HO between the DAA and DLA groups. There was no association between poorer clinical outcomes and the severity of HO.

CONCLUSION

The DAA without a dedicated orthopaedic table is associated with a significant lower incidence of HO than the DLA 6 months after elective THA. Except for the surgical approach, no other factors correlated with the occurrence of HO. Even though a lower HHS was found with severe HO, the correlation between severity of HO and clinical outcomes did not reach statistical significance.

Surgical Triumph Over Huge Nontraumatic Myositis Ossificans of the Gluteal Region in an Epileptic Patient With History of Stroke: A Case Report

Myositis ossificans (MO) is a benign condition where bone forms within muscles due to increased activity of the periarticular tissues. Trauma is the most common cause. Nontraumatic MO is exceedingly rare. We present a rare instance of nontraumatic MO affecting the hip in a 32-year-old patient. The patient had a known case of seizure disorder and also had a history of a cerebrovascular accident (CVA). Despite the absence of trauma or known predisposing factors, the patient developed a sizable mass in the left hip, causing pain and restricted range of motion (ROM). Surgical excision of the mass was successful, resulting in complete removal and subsequent improvement in hip function and pain relief during postoperative recovery. Histopathological examination confirmed the diagnosis of MO. The patient's ROM normalized, and there were no signs of recurrence at the one-year follow-up. This case highlights the importance of recognizing MO in hip pain cases without trauma. Timely surgery through the approach described effectively removes the mass, preventing recurrence without compromising vital structures. It showcases a successful multidisciplinary approach for rare musculoskeletal conditions, offering valuable insights into similar cases.

Heterotopic ossification in primary total hip arthroplasty: risk factor analysis

BACKGROUND

Aim is to identify if age, sex, type of posterolateral approach (mini vs standard), surgical time and time from surgery to drainage removal were independent risk factors for heterotopic ossifications after total hip arthroplasty.

MATERIALS AND METHODS

Patients who underwent a THA with posterolateral approach during a 15 years period were included. The exclusion criteria were absence of X-rays follow-up or HO prophylaxis protocol adoption. The following data were collected: age, sex, type of approach (classical/minimal-invasive), surgical time, time from surgery to drainage removal. Two orthopedic surgeons independently reviewed the 2 years follow-up X-rays and classified the HO according to Brooker classification. Severe HO was defined if HO were classified as major than grade 2. Correlation between severe HO and risk factor has been tested with multivariable analysis.

RESULTS

About 1225 patients were included: mean age of 63.8 years, 504 were men. HO were found in 67.6%. Men showed higher severe HO rate than woman (44.1% vs 29.1%, p = 0.001). Patients older than 65 years showed higher severe HO rate (30.3% vs 39.9%, p = 0.002). Standard posterolateral approach was performed in 75.4% and severe HO rate was 32.8% versus 27.1% in those treated with the minimally invasive approach (p = 0.067). In 75.6% of cases surgery lasted less than 90 min and this group showed a severe HO rate in 29.1%, while patient with longer surgical time showed a rate of 35.7% (p = 0.033). In 47.4% of patients, the drainage was removed in the first post-operative day, in this group severe HO rate was significantly lower than the others: 24.8 versus 36.2% (p = 0.001).

DISCUSSION

Male sex, age older than 65 years, surgical time longer than 90 min and delayed drainage removal are risk factors for severe HO. Patients with one or more of those risk factors should be identified as good candidates for HO prophylaxis.

Mono-articular idiopathic heterotopic ossification in a Coronavirus infected patient admitted in the intensive care unit

Heterotopic ossification (HO) designates a bone tissue formation within an atypical anatomical location and is commonly diagnosed in patients whom have suffered major traumas. The following case report presents a non-traumatic source of HO. A causality is deduced between the HO formation and an important inflammatory reaction originating from a Coronavirus infection. In contrast to other studies not only is the source non traumatic but the HO formation is unilateral. In systemic inflammatory reactions vigilance towards HO should be enhanced especially in patients treated during prolonged periods of time in intensive care units (ICU).

Low-dose Preoperative Unshielded Radiation Is Effective in Heterotopic Ossification Prophylaxis and Does Not Affect Porous Fixation in Total Hip Arthroplasty at 2 Years Minimum Follow-up: A Radiographic Study

BACKGROUND

Heterotopic ossification (HO) is a frequent complication of total hip arthroplasty (THA). HO can cause pain, limitation of range of motion, and instability. Radiation therapy (RT) for HO prophylaxis is well established but may interfere with early porous ingrowth and pullout strength of implants, as suggested by two animal studies. Although shielding of the bone from irradiation may theoretically protect ingrowth, it has been found to reduce RT effectiveness. Despite the popularity of porous implants in THA, the frequency of HO, and use of RT in its prophylaxis, the effect of RT on porous implant fixation in THA has not been previously reported. At our institution, we use unshielded, single-dose, preoperative 700 to 800 centigrays RT for HO prophylaxis in high-risk patients. We hypothesize that this RT protocol is effective and the press-fit technique protects porous implants during early ingrowth; therefore, long-term implant fixation is not compromised.

METHODS

This was a retrospective study aiming to determine fixation of porous THA implants, healing of trochanteric osteotomies, and efficacy of HO prophylaxis with this RT protocol.

RESULTS

Thirty-nine patients with follow-up of 24 to 144 months (average 59.7 months) were included. All 26 porous-coated femoral implants (11 revisions and 15 primary) were well fixed. There were 33 porous-coated acetabular implants (18 revisions and 15 primary). Thirty (91%) were well fixed, and three revision implants (9%) demonstrated radiolucent lines in two zones, but patients were clinically asymptomatic. All nine trochanteric osteotomies healed uneventfully. RT provided effective HO prophylaxis in 33 of 39 hips (85%).

CONCLUSIONS

Single, low-dose, preoperative RT without shielding does not increase aseptic loosening of porous implants manufactured with plasma porous spray or nonunion of extended trochanteric osteotomies. This protocol provides effective HO prophylaxis in high-risk patients undergoing primary and revision THA.

Myositis ossificans revisited - The largest reported case series

INTRODUCTION

Myositis ossificans (MO) is a condition characterised by the formation of non-neoplastic heterotropic ossification in extraskeletal soft tissues.

MATERIAL AND METHODS

We performed a retrospective study of our radiology databases within our tertiary orthopaedic centre to identify all cases of MO, reported on X ray, Magnetic resonance imaging (MRI) and Computed tomography (CT) over the past 13 years (2007-2020).

RESULTS

We identified 68 cases of MO, which were included into our cohort. The average age of our patients was 36 years (range 4-84 years). 73% of cases (n = 50) were found to affect the lower limb muscles with the majority in the quadriceps.

CONCLUSION

We report the largest case series of MO and discuss the demographics, diagnoses and management.

Heterotopic Ossification in Primary Total Hip Arthroplasty: which is the role of drainage?

Background and aim of the work: The Heterotopic Ossification (HO) is a common complication following Total Hip Arthroplasty (THA). Although there is no concordance in Literature regarding the etiopathogenic mechanism, various HO risk factors have been recognized, both related to the patient and associated with the surgical procedureLiterature does not consider the use of intra-articular drainage as a possible risk factor. Our hypothesis is that this item can contribute to the development of HO. Materials and Methods: 425 implants of hip arthroplasty performed between 2014 and 2017 at the Ortopedic Clinic of Udine were included in the study. No patient performed pre-operative or post-operative anti-HO prophylaxis during follow-up. Radiographs of preoperative and postoperative at 1 year were analyzed according to the Brooker Classification.Results: The incidence of HO in patients with intra-articular drainage is 24.6%, while the incidence of HO in patients without intra-articular drainage is 15.3%, with a statistically significant difference. Conclusions: The data obtained suggest to consider the use of intra-articular drainage as a possible intra-operative risk factor for HO. This is a retrospective cohort study, so we need more studies and more robust experimental designs to confirm these results. (www.actabiomedica.it)

Post-Traumatic Heterotopic Ossification: An Old Problem in Need of New Solutions

Heterotopic ossification (HO) is the formation of pathological bone in ectopic sites and it can have serious consequences for functional outcomes. For many years, its main clinical relevance was as a rare complication of elective joint arthroplasty or CNS injury and a number of prophylaxes were developed to mitigate against it in these settings. As a consequence of changes in patterns of wounding and survival in conflicts since the turn of the century, post-traumatic HO has become much more common and case severity has increased. It represents one of the main barriers to rehabilitation in a large cohort of combat-injured patients. However, extant prophylaxes have not been shown to be effective or appropriate in this patient cohort. In addition, the lack of reliable early detection or means of predicting which patients will develop HO is another barrier to effective prevention. This review examines the current state of understanding of post-traumatic HO including the historical context, epidemiology, pathophysiology, clinical issues, currently prophylaxis and detection, management, and potential future approaches. Our aims are to highlight the current lack of effective means of early detection and prevention of HO after major trauma and to stimulate research into novel solutions to this challenging problem. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:1061-1068, 2018.

Heterotopic Ossification in Primary Total Hip Arthroplasty Using the Direct Anterior vs Direct Lateral Approach

BACKGROUND

The formation and severity of heterotopic ossification (HO) may be influenced by type of surgical approach. Our hypothesis was that because of differences in soft tissue dissection, differences exist in HO formation in primary total hip arthroplasty using direct anterior (DA) vs direct lateral (DL) approach.

METHODS

A total of 1482 consecutive patients with DL (736) or DA (746) approach and similar perioperative care protocol during 2009-2011 were retrospectively studied. No patient received prophylactic radiotherapy. Preoperative and 6-month postoperative radiographs were reviewed based on Brooker classification.

RESULTS

The incidence of overall HO was higher in DL (36.1%) vs DA group (19.4%, P < .001) but high-grade HO (Brooker ≥3) was not significantly different among the groups (3.9% for DL and 3.0% for DA groups). No patient required further surgery for HO resection.

CONCLUSION

The type of approach (DA vs DL) did not seem to have a major influence on the short-term incidence of high-grade HO based on this radiographic analysis.

Nontraumatic Myositis Ossificans of Hip: A Case Presentation

In most of the cases trauma is the leading etiology and the nontraumatic myositis ossificans (MO) is a very rare condition. We present an MO case without any trauma occurring. A 36-year-old female patient with a history of pain and restriction of range of motion of the left hip was admitted. Hip motions were restricted with 10–60° of flexion, 10° of internal rotation, 20° of external rotation, 10° of abduction, and 10° of adduction. There was no history of trauma and familial involvement. The biopsy of the lesion revealed mature bone tissue confirming our diagnosis of MO. The mass was removed surgically and postoperatively the patient was treated with a single dose radiotherapy with 800 gyc. MO is a benign and well differentiated bone formation or in other words heterotopic ossification of the muscle tissue. It has a prevalence of less than 1/1 million. Trauma is the most frequent etiological factor seen in almost 60–75% of the cases. Nontraumatic MO is very rare in the literature. Our patient had no history of trauma or familial involvement. Combination of the surgical excision with radiotherapy in the treatment of the MO of the hip may give satisfactory results.

Risks of secondary malignancies with heterotopic bone radiation therapy for patients younger than 40 years

Heterotopic ossification (HO) of the bone is defined as a benign condition in which abnormal bone formation occurs in soft tissue. One of the most common prophylactic treatments for HO is radiation therapy (RT). This study retrospectively reviewed 20 patients younger than the age of 40 who received radiation to prevent HO in a single fraction of 7 Gray. The purpose of this study is to assess the risk of a second malignancy in these patients by recreating their treatment fields and contouring organs at risk to estimate the radiation dose absorbed by normal tissues outside the radiation treatment field. Diagnostic computed tomography (CT) scans for each patient were used to recreate treatment fields and to calculate dose to structures of interest. The distance from the field edge to each structure and its depth was recorded. Dose measurements in a water phantom were performed for the range of depths, distances, and field sizes used in the actual treatment plans. Computer-generated doses were compared to estimates based on measurement. The structure dose recorded was the higher dose generated between the 2 methods. Scatter dose was recorded to the rectum, bladder, sigmoid colon, small bowel, ovaries and utero-cervix in female patients, and prostate and gonads in male patients. In some patients, there is considerable dose received by certain organs from scatter because of their proximity to the radiation field. The average dose to the ovarian region was 4.125Gy with a range of 1.085 to 6.228Gy. The risk estimate for these patients ranged from 0.16% to 0.93%. The average total lifetime risk estimate for the bladder in all patients is 0.22% and the average total lifetime risk estimate for the remainder organs in all patients is 1.25%. In conclusions, proper shielding created from multileaf collimators (MLCs), blocks, and shields should always be used when possible.

Anterior approach versus posterior approach for Pipkin I and II femoral head fractures: A systemic review and meta-analysis

PURPOSE

We performed a meta-analysis, pooling the results from controlled clinical trials to compare the efficiency of anterior and posterior surgical approaches to Pipkin I and II fractures of the femoral head.

METHODS

Potential academic articles were identified from the Cochrane Library, Medline (1966-2015.5), PubMed (1966-2015.5), Embase (1980-2015.5) and ScienceDirect (1966-2015.5) databases. Gray studies were identified from the references of the included literature. Pooling of the data was performed and analyzed by RevMan software, version 5.1.

RESULTS

Five case-control trials (CCTs) met the inclusion criteria. There were significant differences in the incidence of heterotopic ossification (HO) between the approaches, but no significant differences were found between the two groups regarding functional outcomes of the hip, general postoperative complications, osteonecrosis of the femoral head or post-traumatic arthritis.

CONCLUSION

The present meta-analysis indicated that the posterior approach decreased the risk of heterotopic ossification compared with the anterior approach for the treatment of Pipkin I and II femoral head fractures. No other complications were related to anterior and posterior approaches. Future high-quality randomized, controlled trials (RCTs) are needed to determine the optimal surgical approach and to predict other postoperative complications.

LEVEL OF EVIDENCE

III.

Severe heterotopic ossifications after Rockwood type II acromioclavicular joint injury: a case report

INTRODUCTION

Heterotopic ossification (HO) is a benign condition of abnormal bone formation in soft tissue. It is frequently asymptomatic, though it manifests as decreased range of motion in the affected joints that may occur in the shoulder after a substantial traumatic injury and can complicate the functional outcome of the affected upper extremity. However, severe HO is an extremely rare event following acromioclavicular joint (ACJ) injury.

MATERIALS AND METHODS

We are presenting a case of a 29-year-old male patient who had a trauma with resultant Rockwood type II injury. He subsequently complained of left shoulder pain with decreased range of motion 3 years later. HO was diagnosed after X-rays and the severity was assessed with a computerized tomography scan and magnetic resonance imaging. The patient was treated with a combination of pre-operative radiotherapy, surgical excision, mobilization under anesthesia, non-steroidal anti-inflammatory drug (NSAID) therapy and physiotherapy.

RESULTS

At 6-month follow-up, excellent clinical and radiological outcomes were achieved with a Constant score of 92 points, DASH score of 24%, and ASES score 100%, with a full range of motion of the left shoulder. Furthermore, there was no more radiological evidence of HO on plain radiographs.

CONCLUSION

Severe heterotopic ossification after a Rockwood type II ACJ injury in this case was successfully treated with combination of pre-operative radiotherapy, surgical excision and manipulation under anesthesia as well as NSAID therapy and physiotherapy.

Heterotopic ossification following hip arthroplasty: a comparative radiographic study about its development with the use of three different kinds of implants

Background

Our purpose was to record the incidence of heterotopic ossification (HO) following hip replacement by different variables to identify patient groups that are likely to develop HO in the absence of a prophylactic protocol.

Methods

Radiographically, we studied 651 patients having undergone hip joint replacement, evaluating three kinds of implants: ceramic-ceramic-coupled total hip replacement (THR), TriboFit^® with polycarbonate urethane-ceramic coupling and endoprosthesis. Each patient was analysed for HO development by age, gender, diagnosis, presence of previous ossifications, surgical approach and kind of implant. Within the population that developed HO, data were assessed for correlation with severity of ossification graded according to Brooker classification.

Results

The overall incidence of HOs was 59.91 %. The factors increasing their incidence in the univariate analysis were as follows: lower age of the patients with HO (mean 77.6 years, p = 0.0018) than those subjects who did not develop HO (mean 80.2 years); male gender (64.4 %, p = 0.1011); diagnosis of coxarthrosis (72.7 %, p = 0.0001) compared to femur neck fracture (55.9 %, p = 0.0001); presence of previous HO (76.2 %, p = 0.0260); lateral approach (65.5 %) as opposed to anterior-lateral approach (55.6 %, p = 0.0163); and ceramic-ceramic THR (68.1 %) and TriboFit^® (67.0 %) compared to endoprosthesis (51.3 %, p = 0.0001).

During multivariate analysis, the presence of HO after previous hip surgery (p = 0.0324) and the kind of implant (p = 0.0004) showed to be independent risk factors for the development of HO. Analysing the population that developed HO, we found that the severity of ossification by Brooker classification was influenced by gender (p = 0.0478) and kind of implant (p = 0.0093).

Conclusions

In agreement with the literature, our radiographic study confirms the following risk factors of HO development in absence of any prophylactic treatment: male gender, diagnosis of coxarthrosis compared to femur neck fracture, previous HO, surgical approach and kind of implant. In particular, Hardinge-Bauer and Watson-Jones surgical approaches, characterized by a wide exposure of the coxofemoral joint, and ceramic-ceramic THR and TriboFit^® implants significantly increase the development of HO.

Identifying the Cellular Mechanisms Leading to Heterotopic Ossification

Heterotopic ossification (HO) is a debilitating condition defined by the de novo development of bone within non-osseous soft tissues, and can be either hereditary or acquired. The hereditary condition, fibrodysplasia ossificans progressiva is rare but life threatening. Acquired HO is more common and results from a severe trauma that produces an environment conducive for the formation of ectopic endochondral bone. Despite continued efforts to identify the cellular and molecular events that lead to HO, the mechanisms of pathogenesis remain elusive. It has been proposed that the formation of ectopic bone requires an osteochondrogenic cell type, the presence of inductive agent(s) and a permissive local environment. To date several lineage-tracing studies have identified potential contributory populations. However, difficulties identifying cells in vivo based on the limitations of phenotypic markers, along with the absence of established in vitro HO models have made the results difficult to interpret. The purpose of this review is to critically evaluate current literature within the field in an attempt identify the cellular mechanisms required for ectopic bone formation. The major aim is to collate all current data on cell populations that have been shown to possess an osteochondrogenic potential and identify environmental conditions that may contribute to a permissive local environment. This review outlines the pathology of endochondral ossification, which is important for the development of potential HO therapies and to further our understanding of the mechanisms governing bone formation.

Is fixation an option for comminuted femoral head fracture?

Femoral head fracture (Pepkin fracture) is a serious injury that is usually caused by trauma with more incidences in young age. There is no definitive treatment suggested in literature for Pepkin fracture. In this work, a case with class IV Pipkin fracture is presented. Fixation of the fracture was done and the outcomes of the surgical procedure immediately and 6 years after surgery are documented.

Radiotherapy for non-malignant disorders: state of the art and update of the evidence-based practice guidelines

Every year in Germany about 50,000 patients are referred and treated by radiotherapy (RT) for "non-malignant disorders". This highly successful treatment is applied only for specific indications such as preservation or recovery of the quality of life by means of pain reduction or resolution and/or an improvement of formerly impaired physical body function owing to specific disease-related symptoms. Since 1995, German radiation oncologists have treated non-malignant disorders according to national consensus guidelines; these guidelines were updated and further developed over 3 years by implementation of a systematic consensus process to achieve national upgraded and accepted S2e clinical practice guidelines. Throughout this process, international standards of evaluation were implemented. This review summarizes most of the generally accepted indications for the application of RT for non-malignant diseases and presents the special treatment concepts. The following disease groups are addressed: painful degenerative skeletal disorders, hyperproliferative disorders and symptomatic functional disorders. These state of the art guidelines may serve as a platform for daily clinical work; they provide a new starting point for quality assessment, future clinical research, including the design of prospective clinical trials, and outcome research in the underrepresented and less appreciated field of RT for non-malignant disorders.

Postencephalitic bilateral heterotopic ossification of the hip in a pediatric patient

Heterotrophic ossification has been defined as abnormal formation of mature lamellar bone in soft tissues. Neurogenic heterotopic ossification has been well described in adults. However, it is uncommon in the pediatric population, where it has been noted to recede in some cases. There are very few reports of postmeningitis bilateral involvement of the hip. We describe a case of bilateral heterotopic ossification of hip in a 13-year-old female. The patient had a history of encephalitis, prolonged vegetative state, and intubation for 6 weeks. The patient had fixed deformities of both hips in 30° of flexion and 30° of external rotation. A diagnosis of Brooker stage 4 heterotopic ossification was made. The patient underwent a staged procedure for excision of the heterotopic mass. Postoperatively, the patient was administered radiotherapy and indomethacin for 6 weeks. At the 2-year follow-up, there was no recurrence and both the hips were mobile with full range of motion. The patient was satisfied with the result. The incidence of heterotopic ossification is less than that observed in the adult population and alkaline phosphatase levels are not significantly elevated unlike in adults. To our knowledge, there is no reported case of postencephalitic bilateral anterior heterotopic ossification of the hip in a pediatric patient treated with excision successfully. Postencephalitic heterotopic ossification in children is an uncommon condition. This condition can be treated successfully with surgical excision, combined postoperative protocol of radiotherapy, indomethacin, and immediate postoperative mobilization of the joint.

DEGRO practical guidelines for the radiotherapy of non-malignant disorders - Part IV: Symptomatic functional disorders

PURPOSE

To summarize the updated DEGRO consensus S2e guideline recommendations for the treatment of benign symptomatic functional disorders with low-dose radiotherapy.

MATERIALS AND METHODS

This overview reports on the role of low-dose radiotherapy in the treatment of functional disorders in cases of heterotopic ossification (HO) and Graves orbitopathy (GO). The most relevant aspects of the DEGRO S2e Consensus Guideline "Radiation Therapy of Benign Diseases 2014" regarding diagnostics, treatment decision, dose prescription, as well as performance of radiotherapy and results are summarized.

RESULTS

For both indications (HO, GO), retrospective and some prospective analyses have shown remarkable effects in terms of symptom relief. Nevertheless, the level of evidence (LoE) and the grade of recommendation (GR) vary: LoE 1-2 and GR A-B (HO), LoE 2 and GR B (GO).

CONCLUSION

Low-dose radiotherapy for benign symptomatic functional disorders has proven to be effective, according to different authors, for 25-100 % of the patients studied and therefore it may be a reasonable prophylactic and therapeutic option if noninvasive or invasive methods have been used without persistent success. For HO, a single-fraction dose of 7-8 Gy or fractionated radiation with five fractions of 3.5 Gy is recommended. For GO, single-fraction doses of 0.3-2.0 Gy, and total doses of 2.4-20 Gy/series, applied in one daily fraction are recommended.

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

INTRODUCTION

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Cancer risk estimates from radiation therapy for heterotopic ossification prophylaxis after total hip arthroplasty

PURPOSE

Heterotopic ossification (HO) is a frequent complication following total hip arthroplasty. This study was conducted to calculate the radiation dose to organs-at-risk and estimate the probability of cancer induction from radiotherapy for HO prophylaxis.

METHODS

Hip irradiation for HO with a 6 MV photon beam was simulated with the aid of a Monte Carlo model. A realistic humanoid phantom representing an average adult patient was implemented in Monte Carlo environment for dosimetric calculations. The average out-of-field radiation dose to stomach, liver, lung, prostate, bladder, thyroid, breast, uterus, and ovary was calculated. The organ-equivalent-dose to colon, that was partly included within the treatment field, was also determined. Organ dose calculations were carried out using three different field sizes. The dependence of organ doses upon the block insertion into primary beam for shielding colon and prosthesis was investigated. The lifetime attributable risk for cancer development was estimated using organ, age, and gender-specific risk coefficients.

RESULTS

For a typical target dose of 7 Gy, organ doses varied from 1.0 to 741.1 mGy by the field dimensions and organ location relative to the field edge. Blocked field irradiations resulted in a dose range of 1.4-146.3 mGy. The most probable detriment from open field treatment of male patients was colon cancer with a high risk of 564.3 × 10(-5) to 837.4 × 10(-5) depending upon the organ dose magnitude and the patient's age. The corresponding colon cancer risk for female patients was (372.2-541.0) × 10(-5). The probability of bladder cancer development was more than 113.7 × 10(-5) and 110.3 × 10(-5) for males and females, respectively. The cancer risk range to other individual organs was reduced to (0.003-68.5) × 10(-5).

CONCLUSIONS

The risk for cancer induction from radiation therapy for HO prophylaxis after total hip arthroplasty varies considerably by the treatment parameters, organ site in respect to treatment volume and patient's gender and age. The presented risk estimates may be useful in the follow-up studies of irradiated patients.

Computerized tomography-based radiotherapy improves heterotopic ossification outcomes

PURPOSE

To report the impact of computerized tomography (CT) based radiotherapy (RT) on heterotopic ossification (HO) outcomes.

METHODS

This is a single institution, retrospective study of 532 patients who were treated for traumatic acetabular fractures (TAF). All patients underwent open-reduction internal-fixation (ORIF) of the TAF followed by RT for HO prophylaxis. Postoperative RT was delivered within 72h, in a single fraction of 7Gy. The patients were divided into 2 groups based on RT planning: CT (A) vs. clinical setup (B).

RESULTS

At a median follow up of 8years the incidence of HO was 21.6%. Multivariate regression analysis revealed that group (A) vs. (B) had HO incidence of 6.6% vs. 24.6% (p<0.001), respectively. Furthermore, HO Brooker grade ≥3 was observed in 2.2% vs. 10.8% (p=0.007) in group (A) vs. (B), respectively. Thus, the odds of developing HO and Brooker grades ≥3 were 4.7 and 4.5 times higher, respectively, in patients who underwent clinical setup.

CONCLUSION

Our data suggest that using CT based RT allowed more accurate delineation of the tissues and better clinical outcomes. Although CT-based RT is associated with additional cost the efficacy of CT-based RT reduces the risk of HO, thereby decreasing the need for additional surgical interventions.

Myositis ossificans circumscripta, secondary to high-velocity gunshot and fragment wound that causes sciatica

This report concerns an unusual cause of sciatica. The case presented is of a young man with myositis ossificans that resulted in sciatica and was treated with en bloc excision and low-dose radiotherapy and indomethacine. The aim of this study was to explain the different diagnostic properties of myositis ossificans around the hip and non-classic causes of sciatica.

Bilateral heterotopic ossification after bilateral hip arthroplasty in a geriatric patient

The case of a geriatric patient with total hip arthroplasty for coxarthrosis and an inpatient fall 12 days after the first operation is reported. Six weeks after the first operation, the patient reported new pain in the area of both hips and thighs. X-ray and scintigraphy confirmed the diagnosis of bilateral heterotopic ossification. NSAID therapy was started, and rapid improvement was observed. At discharge, the patient was able to walk with aids in- and outside. At the 12-month follow-up, x-ray control showed Brooker state 3 for the right and 4 for the left hip. Walking ability did not change during follow-up.

Shaping the military wound: issues surrounding the reconstruction of injured servicemen at the Royal Centre for Defence Medicine

The conflict in Afghanistan has produced injuries similar to those produced from military conflicts for generations. What distinguishes the modern casualty of the conflict in Afghanistan from those of other conflicts is the effectiveness of modern field medical care that has led to individuals surviving with injuries, which would have been immediately fatal even a few years ago. These patients present several challenges to the reconstructive surgeon. These injured individuals present early challenges of massive soft-tissue trauma, unstable physiology, complex bony and soft-tissue defects, unusual infections, limited reconstructive donor sites, peripheral nerve injuries and traumatic amputations. Late challenges to rehabilitation include the development of heterotopic ossification in amputation stumps. This paper outlines the approach taken by the reconstructive team at the Royal Centre for Defence Medicine in managing these most difficult of reconstructive challenges.

Selective COX-2 inhibitor versus nonselective COX-1 and COX-2 inhibitor in the prevention of heterotopic ossification after total hip arthroplasty: a meta-analysis of randomised trials

Whether selective cyclo-oxygenase-2 (COX-2) inhibitors are equally effective compared to nonselective NSAIDs for the prevention of heterotopic ossification (HO) after total hip arthroplasty (THA) is still unclear. We carried out a comprehensive search strategy, in which only randomised controlled trials were included. Two reviewers independently assessed methodological quality and extracted outcome data. Analyses were performed using Stata version 10.0. Four eligible randomised controlled trials totalling 808 patients were included. Meta-analysis results showed that no statistically significant difference was found in overall incidence of HO (RR 1.08; 95% CI 0.71-1.64), incidence of moderate severe HO (Brooker II and III) (RR 0.83; 95% CI 0.48-1.42) and any grade of Brooker classification between two groups. In summary, the selective COX-2 inhibitors are equally effective as nonselective NSAIDs for the prevention of HO after THA. Considering the gastrointestinal side effects of nonselective NSAIDs, we recommend selective COX-2 inhibitors for the prevention of HO after THA. However, future well-designed, randomised controlled trials are still needed to further confirm our results.

Elevated levels of numerous cytokines in drainage fluid after primary total hip arthroplasty

As cytokines are involved in wound healing and other inflammatory processes, it could be valuable to measure their levels at the operative site. This study was conducted to investigate whether different cytokines are measurable in drainage fluid and, when measurable, whether we can find a difference in cytokine levels between one and six hours postoperatively. Samples from the drainage system in 30 consecutive patients undergoing primary total hip replacement were collected at one and six hours after closure of the wound. Levels of several cytokines were measured in the drainage fluids. A significant elevation of almost all cytokines was observed between the sample after one hour and six hours postoperatively. We found a strong correlation between the different pro-inflammatory cytokines. The IL-6 to IL-10 ratio were also raised, showing a pro-inflammatory predominance. Levels were much higher than those previously shown in serum.

Impact of surgical approach on postoperative heterotopic ossification and avascular necrosis in femoral head fractures: a systematic review

Heterotopic ossification (HO) and avascular necrosis (AVN) have been identified as post-traumatic complications of femoral head fractures and may lead to a restriction in hip function and permanent disability. The question of which surgical approach is the best for the femoral head fracture and its relationship with HO and AVN remains controversial. We conducted a systematic review in which all published studies were evaluated. We performed a literature search in MEDLINE, PubMed, EMBASE, MD Consult, and the Cochrane Controlled Trial Register from 1980 to April 2009. We found ten appropriate studies, describing 176 patients. A lower percentage of patients treated with a trochanteric flip approach was reported with HO than patients treated with anterior or posterior approach (33.3% versus 42.1% and 36.9%, respectively), although the difference was not statistically significant. The incidence of AVN was highest in the posterior approach group (16.9%), and subsequently with the trochanteric flip approach (12.5%) and the anterior group (7.9%). The investigators concluded that the use of the anterior approach may result in a higher risk for HO and the posterior approach may result in a higher risk for AVN. A new, posterior-based approach of trochanteric flip seems to be a better approach for femoral head fractures. A further case-control study would be appropriate to confirm the findings in our systematic review.

Heterotopic ossification in burns: our experience and literature reviews

PURPOSES

Heterotopic ossification (HO) is an uncommon, but high profile complication of burns. In this paper, a retrospective study was undertaken to evaluate our treatment and results of HO. Relevant literature was also reviewed to search for new advances in prevention and management for patients with HO after burns.

MATERIALS AND METHODS

A retrospective study was undertaken in Chang Gung Memorial Hospital, Linkou. We collected 12 patients who suffered from HO after burn and received operation in our hospital between June 2000 and September 2007. The data was expressed as mean.

RESULTS

Patients' gender distribution was 10 males and 2 females. The mean age was 43 years old (range, 30-59). Causes of burn were flame burn (75%), scald burn (8%), contact burn (8%), and high-voltage electrical burn (8%). Mean TBSA was 39% (range, 8-90%). Nine of 12 patients (75%) were admitted to intensive care unit (ICU) and 6 (50%) received mechanical ventilator support. The mean ICU stay was 82 days (range, 26-240 days). The elbow was the most commonly affected joint (92%). The outcome of surgery was acceptable in all elbows at the time of surgery. The mean ROMs before surgery were 31 degrees (range, 0-75 degrees). The mean ROMs after surgery were 99 degrees (range, 70-115 degrees); mean gain was 68 degrees (range, 35-115 degrees). One (8%) patients had recurrent HO after operation. The mean outpatient department follow-up time was 14.6 months (range, 1-40 months). The incidence of HO in our burn center is 0.15%.

CONCLUSION

Although HO after burn is uncommon, physicians should keep the complication in mind. When burn patients complain decreased ROM or "locking sign" in their joints, X-ray examination is indicated to rule out HO. Surgery is the treatment of choice when the diagnosis of HO is confirmed.

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.

Aspirin decreases the prevalence and severity of heterotopic ossification after 1-stage bilateral total hip arthroplasty for osteoarthrosis

Heterotopic ossification (HO) is a frequent complication after total hip arthroplasty (THA). We retrospectively evaluated the prevalence and severity of HO in patients with osteoarthrosis who underwent 1-stage bilateral THA (OSBTHA) and compared those who received aspirin with those who received Coumadin for postoperative chemothromboprophylaxis. The aspirin group consisted of 66 patients (132 hips), with a mean age of 64 years (SD, 8.5). The Coumadin group consisted of 67 patients (134 hips), with a mean age of 60 years (SD, 10.2). Overall, HO was detected in 124 hips (46.6%). There were 43 hips (32.5%) with HO in the aspirin group and 81 (60.4%) in the Coumadin group (P < .00005). Aspirin significantly decreases the prevalence and severity of HO in comparison to Coumadin after OSBTHA.

Levothyroxin inhibits heterotopic ossification: an experimental study in rabbits

BACKGROUND

Heterotopic ossification is a common complication of surgery or trauma.

OBJECTIVE

To investigate the efficacy of levothyroxin in inhibition of heterotopic ossification.

METHODS

Heterotopic ossification was induced in 36 rabbits in three identical groups by injecting 2 mL of bone marrow in right thigh. To prevent heterotopic ossification, levothyroxin (20 microg/kg) was administered orally daily for 4 weeks to two groups of adult rabbits: group A (preload)--starting 1 week preceding bone marrow injection; group B--started on day of injection; and group C--control group (no levothyroxin) in a rabbit model. After 5 weeks the rabbits were evaluated by radiographs for evidence of ossification. At the end of the study histologic samples were taken from all the thighs.

RESULTS

Imaging and histologic studies showed, with statistical significance, almost complete prevention of heterotopic ossification in group A (preload) and a marked decrease in group B, when compared with the controls.

CONCLUSIONS

Levothyroxin demonstrated efficacy in preventing heterotopic ossification.

Total hip arthroplasty for ankylosed hip secondary to heterotopic ossification

Heterotopic ossification (HO) secondary to traumatic brain injury occurs at various sites and most commonly at the elbow, shoulder, and hip. There are few published reports on the assessment and surgical resection techniques of HO. A complete preoperative physical examination and radiologic assessment with a computed tomographic scan are important for the thorough evaluation of a patient. We describe a patient with neurogenic HO of the hip secondary to traumatic brain injury who underwent a total hip arthroplasty (THA). In selected patients with hip HO, THA supplemented with postoperative radiotherapy and indomethacin prophylaxis can facilitate progressive functional movements of the hip. To our knowledge, there is no report in the English literature of a THA being preformed for HO.

The prophylaxis and treatment of heterotopic ossification following lower limb arthroplasty

Heterotopic ossification following joint replacement in the lower limb occurs in 3% to 90% of cases. Higher grades of heterotopic ossification can result in significant limitation of function and can negate the benefits of joint replacement. The understanding of the pathophysiology of this condition has improved in recent years. It would appear to be related to a combination of systemic and local factors, including over-expression of bone morphogenetic protein-4. There is currently little evidence to support the routine use of prophylaxis for heterotopic ossification in arthroplasty patients, but prophylaxis is recommended by some for high-risk patients. Radiotherapy given as one dose of 7 Gy to 8 Gy, either pre-operatively (< four hours before) or post-operatively (within 72 hours of surgery), appears to be more effective than indometacin therapy (75 mg daily for six weeks). In cases of prophylaxis against recurrent heterotopic ossification following excision, recent work has suggested that a combination of radiotherapy and indometacin is effective. Advances in our understanding of this condition may permit the development of newer, safer treatment modalities.