Effects of heterotopic bone formation on outcome after hip arthroplasty

Efficacy of ibuprofen and indomethacin as prophylaxis of heterotopic ossification: a comparative study

The prophylactic action of non-steroidal anti-inflammatory drugs (NSAIDs) in heterotopic ossification (HO) was first described following analgesic therapy with indomethacin. Following that evidence, several compounds have been successfully used for prophylaxes of HO. Ibuprofen has been also proposed for the prevention of HO following THA. The present study compared the administration of ibuprofen for three weeks versus indomethacin as prophylaxis for HO following primary THA. In all THA procedures, pre- and post-operative protocols were conducted in a highly standardized fashion. The type of HO prophylaxis (indomethacin 100 mg/daily or ibuprofen 100 mg/daily) was chosen according to a chronological criterion: from 2017 to 2019 indomethacin was used, whereas from 2019 to 2022 ibuprofen was administered. In case of allergy or intolerance to NSAIDs, no prophylaxis was performed, and patients were included as a control group. All patients who underwent an anteroposterior radiography of the pelvis at a minimum of 12 months following THA were considered for inclusion. On admission, the age and sex of the patients were recorded. Moreover, the causes of osteoarthritis and the date of surgery were recorded. The grade of HO was assigned by a blinded assessor who was not involved in the clinical management of the patients. The modified Brooker Staging System was used to rate the efficacy of the interventions. Data from 1248 patients were collected. 62% (767 of 1248 patients) were women. The mean age was 67.0 ± 2.9 years. The mean follow-up was 21.1 ± 10.8 months. In the ibuprofen group, 73% of patients evidenced Brooker 0, 17% Brooker I, and 10% Brooker II. In the indomethacin group, 77% of patients evidenced Brooker 0, 16% Brooker I, 6% Brooker II. No patient in the ibuprofen and indomethacin group developed Brooker III or IV. In the control group, 64% of patients evidenced Brooker 0, 21% Brooker I, 3% Brooker II, and 12% Brooker III. No patient in the control group developed Brooker IV HO. Concluding, three weeks of administration of ibuprofen demonstrated similar efficacy to indomethacin in preventing HO following primary THA. The prophylaxis with ibuprofen or indomethacin was more effective in preventing HO compared to a control group who did not receive any pharmacological prophylaxis.

A systematic review and meta-analysis of cemented and uncemented bipolar hemiarthroplasty for the treatment of femoral neck fractures in elderly patients over 60 years old

Background

Currently, whether bone cement can be applied in bipolar hemiarthroplasty to treat femoral neck fractures (FNFs) in elderly patients is controversial. The aim of this systematic review and meta-analysis was to compare the effectiveness and safety of cemented bipolar hemiarthroplasty (CBH) versus uncemented bipolar hemiarthroplasty (UCBH) in the treatment of FNFs among elderly patients over 60 years old.

Materials and methods

The Pubmed, Web of science, Cochrane Library and EMBASE databases were searched comprehensively for relevant articles from their inception to May 2022. Studies about comparing outcomes between CBH and UCBH for FNFs in elderly patients aged more than 60 years were included. Outcomes including operation time, intra-operative blood loss, length of hospital stay, wound infections, residual pain, revisions, re-operations, complications related to prosthesis, general complications, and mortality. The Review Manager 5.3 software provided by the Cochrane Collaboration Network was used to perform the meta-analysis of comparable data.

Results

A total of 6 randomized controlled trials (RCTs) and 9 observational studies were included in this analysis, with 33,118 patients (33,127 hips). Results of the meta-analysis indicated that the operation time [WMD = 13.01 min, 95% CI (10.79, 15.23)], intra-operative blood loss [WMD = 80.57 ml, 95% CI (61.14, 99.99)], incidence of heterotrophic ossification [OR = 2.07, 95% CI (1,14, 3.78)], were increased in the CBH group but the incidence of intra-operative fractures [OR = 0.24, 95% CI (0.07, 0.86)], periprosthetic fractures [OR = 0.24, 95% CI (0.18, 0.31)], aseptic loosening of prosthesis [OR = 0.20, 95% CI (0.09, 0.44)], wound infections [OR = 0.80, 95% CI (0.68, 0.95)] and re-operation rates [OR = 0.61, 95% CI (0.54, 0.68)] were lower in the CBH group by comparison with the UCHB group. However, there were no significant differences in residual pain, length of hospital stay, prosthetic dislocation, prosthetic subsidence (> 5 mm), acetabulum erosion, revisions, pulmonary infections, pulmonary embolisms, urinary tract infections, deep venous thromboses, decubitus, cardiovascular accidents (arrhythmia/myocardial infarction), and respiratory failure between the two groups. In terms of mortality, perioperative mortality (within 72 h) [OR = 2.39, 95% CI (1.71, 3.32)] and 1-week mortality postoperatively [OR = 1.22, 95% CI (1.05, 1.41)] in CBH group were higher than those in UCBH group, but there were no significant differences in mortality at 1 month, 3 months, 1 year, and 2 years postoperatively between CBH group and UCBH group.

Conclusion

This meta-analysis found that elderly patients over 60 years old with FNFs who underwent CBH had longer operation time, higher incidence of heterotrophic ossification, intra-operative blood loss, and mortality within 72 h of operation and at 1-week postoperatively, but lower incidence of periprosthetic fractures, aseptic loosening of prosthesis, intra-operative fractures, wound infections and re-operations. Other outcomes were not significantly different between the two groups.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42021274253.

Efficacy of NSAIDs versus radiotherapy for heterotopic ossification prophylaxis following total hip arthroplasty in high-risk patients: a systematic review and meta-analysis

BACKGROUND

The aims of this systematic review were: (1) to investigate the prophylactic effect of radiotherapy (RT) and NSAIDs in high-risk patients following total hip arthroplasty (THA); and (2) to compare the efficacy of non-selective and COX-II selective NSAIDs in preventing post-THA HO, utilising a meta-analysis of randomised control studies.

METHODS

The PubMed, Embase, and Cochrane Databases were searched for articles regarding HO following THA in March 2019. Studies were included if they contained data regarding HO incidence after THA or contained data regarding HO prophylaxis comparison of NSAIDs and/or RT in terms of dosage or duration.

RESULTS

24 studies reported on populations that were not at high-risk for HO. These studies reported between 47.3% and 90.4% of their patient populations had no HO formation; between 2.8% and 52.7% had mild formation; and between 0.0% and 10.4% had severe formation. A total of 13 studies reported on populations at high-risk for HO. Studies analysing RT in high-risk patients reported between 28.6% and 97.4% of patients developed no HO formation; between 1.9% and 66.7% developed mild HO formation; and between 0.0% and 11.9% developed severe HO formation. Studies analysing NSAID treatment among high-risk populations reported between 76.6% and 88.9% had no HO formation; between 11.1% and 23.4% had mild HO formation, and between 0.0% and 1.8% had severe HO formation. 9 studies were identified as randomised control trials and subsequently used for meta-analysis. The relative risk for COX-II in developing any HO after THA was not significantly different compared to non-selective NSAIDs (RR 1.00; CI, 0.801-1.256; p = 0.489).

CONCLUSIONS

NSAIDs prophylaxis for HO may have better efficacy than RT in high-risk patients following THA. Non-selective and COX-II selective NSAIDs have comparable efficacy in preventing HO. Factors such as medical comorbidities and side-effect profile should dictate the prophylaxis recommendation.

Heterotopic ossification after total hip arthroplasty: radiological comparison between a direct anterior approach without an orthopaedic table and a posterior approach

INTRODUCTION

Heterotopic ossification (HO) occurs in almost ⅓ of total hip arthroplasties (THAs). A direct anterior approach (DAA) with an orthopaedic table is less likely to cause HO than a posterior approach. Without an orthopaedic table, the exposure of the femur requires additional soft tissue release. Soft tissue trauma leads to the production of HO inductors. Our study evaluated the incidence of HO 6 months after THA and compared the results between DAAs without an orthopaedic table and posterior approaches.

METHODS

Retrospectively, 164 consecutive, primary THAs were included: 76 through a posterior approach and 88 through a DAA. The main objective was to measure the presence of HO on pelvis radiography 6 months after surgery.

RESULTS

The incidence of HO was significantly higher in the DAA group than in the posterior approach group (47.7% vs. 27.6%, respectively; p < 0.01). The overall incidence of HO was 38.4%. No significant difference was found between the 2 approaches regarding the severity of HO. No significant risk factor for HO was identified other than the surgical approach.

DISCUSSION

In our study, the incidence of HO after THA in patients undergoing DAA without an orthopaedic table was higher than in patients undergoing a posterior approach after 6 months of follow-up. This result is closely related to the surgical trauma. It suggests that the minimally invasive feature of a surgical approach cannot be dissociated from the overall conditions in which it is performed.

A comprehensive update on the pharmacological management of heterotopic ossification following hip arthroplasty: a level I evidenced based expert opinion

INTRODUCTION

Heterotopic ossification (HO) of the hip joint may happen accompanying skeletal muscle trauma or surgical procedures. The pharmacological prophylaxis of heterotopic ossification (HO) following total hip arthroplasty (THA) is debated.

AREAS COVERED

This expert opinion aims to systematically investigate the efficacy of current pharmacological options as prophylaxis for HO following THA.

EXPERT OPINION

The current evidence identified celecoxib, naproxen, and diclofenac as best option for the prevention of HO in patients who undergo primary THA. The most appropriate pharmacotherapy for the prevention of HO is still debated and should be customized according to patients' comorbidities and medical history. For patients with cardiovascular comorbidities, naproxen, or diclofenac should be considered along with proton pump inhibitors to prevent gastrointestinal complications. For patients with history of gastrointestinal disease, celecoxib can be recommended. These conclusions must be considered within the limitations of the present investigation. Between studies, heterogeneities in the administration protocols were evident. In some RCTs, the length of the follow-up was shorter than 12 months. The current clinical practice would benefit of high-quality recommendations and the development of the shared official guidelines.

Simplified biplanar classification for heterotopic ossification is more predictive of patient-reported outcomes than the Brooker classification after anterior total hip arthroplasty

BACKGROUND

Heterotopic ossification (HO) commonly occurs after total hip arthroplasty (THA) and can adversely impact clinical outcomes. The purpose of this study is to propose a more reliable HO grading method that is better predictive of patient-reported outcomes (PROs) after THA than the Brooker classification.

METHODS

513 THAs (62 ± 10 years old) were reviewed. The incidence and grade of HO was evaluated using the Brooker grading system and a simplified biplanar classification system (grade 1: ⩾1 cm between bone on both anteroposterior and lateral views, grade 2: <1 cm between bone on either view). The modified Harris Hip Score (mHHS), Forgotten Joint Score (FJS), and visual analogue scale (VAS) for pain were collected at minimum of 2 years after surgery and were compared between HO grades using multiple regression models.

RESULTS

The incidence of HO varied by Brooker grade (grade 1, 23.4%; grade 2, 22.4%; grade 3, 7.2%; grade 4, 0%) and biplanar grade (grade 1: 45.6%; grade 2: 7.4%). The biplanar classification demonstrated higher interobserver reliability than the Brooker classification (κ = 0.95 and 0.91, respectively). Brooker grade 3 HO decreased the mHHS by 6.5 (standard error: 2.7) but did not have a significant effect on FJS or VAS. Biplanar grade 2 HO decreased the mHHS by 9.9 (standard error: 2.7), the FJS by 12.9 (standard error: 4.51) and increased the VAS pain score by 0.81 (standard error: 0.35). The Cox test was used to compare the fit of regression models and determined the biplanar classification was a significantly better predictor than the Brooker classification (p < 0.001).

CONCLUSIONS

Biplanar grade 2 HO had a significant negative influence on PROs. Contrary to previous literature, these results show clinical significance of non-bridging HO. Compared with the Brooker classification, the biplanar classification has greater interobserver reliability and is more predictive of outcomes after THA.

Heterotopic Ossification Following Arthroplasty for Femoral Neck Fracture

BACKGROUND

Heterotopic ossification (HO) is a frequent complication following hip surgery. Using data from the Hip Fracture Evaluation with Alternatives of Total Hip Arthroplasty versus Hemiarthroplasty (HEALTH) trial, we aimed to (1) determine the prevalence of HO following total hip arthroplasty (THA) for femoral neck fracture in patients ≥50 years of age, (2) identify whether HO is associated with an increased risk of revision surgery within 24 months after the fracture, and (3) determine the impact of HO on functional outcomes.

METHODS

We performed a multivariable Cox regression analysis using revision surgery as the dependent variable and HO as the independent variable. We compared Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores between participants with and those without HO at 24 months.

RESULTS

Of 1,441 participants in the study, 287 (19.9%) developed HO within 24 months. HO was not associated with subsequent revision surgery. Grade-III HO was associated with statistically significant and clinically relevant deterioration in the total WOMAC score, which was mainly related to the function component of the score, compared with grade I or II.

CONCLUSIONS

The impact of grade-III HO on the functional outcomes and quality of life after THA for hip fracture is clinically important, and HO prophylaxis for selected high-risk patients may be appropriate.

LEVEL OF EVIDENCE

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Etoricoxib is safe and effective in preventing heterotopic ossification after primary total hip arthroplasty

Background

Heterotopic ossifications are a common complication after total hip arthroplasty. Low-dose radiation therapy and non-steroidal anti-inflammatory drugs have proven to effectively reduce the rate of heterotopic ossification after total hip arthroplasty. However, a low number of studies describe an equal efficiency of etoricoxib. This work shows first results on the examination of a larger group with 194 subjects to analyze efficiency and rate of side effects under treatment with etoricoxib.

Methods

Clinical examinations were performed the day before surgery and after at least 12 months. The survey of clinical and functional outcome was done with Harris Hip Score (HHS). Conventional antero-posterior radiographs and second plane in frog leg position were assessed.

Results

In total, 14 undesirable side effects (7.4%) and only four early terminations of therapy (2.1%) were documented. A complete 1-year follow-up examination including radiographs could be done in 143 subjects (79.4%). Only 28 subjects (19.6%) developed heterotopic ossifications from which 92.9% were classified in type 1 and 7.1% in type 2 using the method described by Brooker. The results do not show correlations with body mass index, extended treatment (more than ten days), or clinical and functional outcome (measured by “Harris Hip Score”). However, male subjects show a significantly higher rate of heterotopic ossifications.

Conclusions

The investigations presented in this study confirm a good efficiency of etoricoxib for the prevention of heterotopic ossifications in comparison with classical methods such as radiation or drug therapy and show a low rate of undesirable side effects.

The Impact of Heterotopic Ossification on Self-Reported Outcomes After Total Hip Arthroplasty Using the Direct Anterior Approach

BACKGROUND

Heterotopic ossification (HO) is a known finding after total hip arthroplasty (THA) that potentially affects clinical outcomes. The incidence of HO is related to various factors, including soft-tissue trauma, postoperative medication, surgical approach, and the surgeon's experience. Because use of the direct anterior approach (DAA) is gaining popularity, we aimed (1) to determine the incidence of HO after DAA-THA and (2) to evaluate the impact of HO on patient-reported outcomes (PROs).

METHODS

We retrospectively reviewed 401 THAs (67 ± 10 years old, 210 men). The incidence and grade of HO were evaluated using the Brooker classification with anteroposterior and lateral radiographs. PROs were collected with use of the Oxford Hip Score (OHS) and the Core Outcome Measures Index (COMI)-Hip and were correlated with HO grades using generalized multiple regression models.

RESULTS

The incidence of HO was 29.9% on the anteroposterior radiographic views (Brooker grade 1, 14.5%; grade 2, 11.1%; grade 3, 2.7%; and grade 4, 0.57%); the lateral radiographic views detected 9% additional HO when compared with the anteroposterior radiographs alone (Brooker grade 1, 8%, and grade 2, 1%). HO was more frequent in men. The American Society of Anesthesiologists (ASA) grade, age in women, and higher body mass index (BMI) in men were associated with higher HO grades. A transverse "bikini" incision was associated with a lower rate (4%) of Brooker grades 3 and 4 HO when compared with a longitudinal incision (12%). A Brooker grade of 0 to 3 HO did not impact outcomes. Only Brooker grade-4 HO was associated with significantly worse PROs; however, pain was not affected.

CONCLUSIONS

Low-grade HO after DAA-THA is not uncommon, and its rate is underestimated when anteroposterior radiographic views are evaluated without lateral views. The risk factors for developing HO in our cohort were an ASA grade of >3, male sex (especially with a high BMI), older age in women, and use of longitudinal incisions. With use of the bikini incision, patients had lower rates of severe HO, but mostly senior surgeons with more experience performed their surgery. Age, ASA grade, experience level of the surgeon, and Brooker grade-4 HO all had a significant influence on PROs. Clinically important HO (Brooker grade 4) remains rare after DAA-THR.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Influence of prior hip arthroscopy on outcomes after hip arthroplasty: A meta-analysis of matched control studies

BACKGROUND

No meta-analysis exists elucidate the impact of prior hip arthroscopy on the outcomes of subsequent hip arthroplasty. The purpose of this study was to systematically review the current evidence in the literature to ascertain if prior hip arthroscopy leads to inferior outcomes after hip arthroplasty.

METHODS

PUBMED, Scopus, EMBASE, and Cochrane Library databases were searched on May 20, 2019. Only English publications were included. The primary outcomes were postoperative complication, revision, and reoperation. Secondary outcomes included Harris Hip Score (HHS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), operative time, and estimated blood loss.

RESULTS

Eleven studies with a total of 1227 patients were included. The pooled data revealed that patients with prior hip arthroscopy were associated with higher risks for any postoperative complication (P < .00001), dislocation (P = .03), revision (P = .03), and reoperation (P = .02) following subsequent hip arthroplasty. However, there were no significant differences in infection rate (P = .22), HHS (P = .09), WOMAC (P = .19), operative time (P = .52), and estimated blood loss (P = .17) between the groups.

CONCLUSIONS

Patients with prior hip arthroscopy are at increased risks for any postoperative complication, dislocation, revision, and reoperation following subsequent hip arthroplasty. However, prior hip arthroscopy does not appear to have an impact on the functional outcomes and intraoperative outcomes.

Size of ischial fibro-ostosis is associated with heterotopic ossification after total hip arthroplasty

PURPOSE

The hypothesis of the present study was that degenerative fibro-ostosis (FO) of the ischial hamstring tendon insertion is a risk factor for heterotopic ossification (HO) following THA.

METHODS

We followed 103 consecutive patients (43 males, 60 females, mean age 61 years) who underwent unilateral cementless THA for primary hip osteoarthritis and investigated the incidence of HO within the first 12 months after surgery. On pre-operative radiographs, a standardized evaluation for FO of the ischial hamstring tendon insertion concerning horizontal, vertical, and square dimensions was performed. HO was classified according to Brooker on radiographs at 12 months post-operatively.

RESULTS

At follow-up, 56 patients (54%) had no radiographic evidence of HO, 23 (22%) were classified as Brooker I, 17 (17%) as II, 6 (6%) as III, and 1 (1%) as IV, respectively. Patients with post-operative HO had significantly greater vertical (3.0 mm vs. 2.3 mm, p = 0.001) and horizontal (47.9 mm vs. 39.1 mm, p = 0.025) dimensions of FO than patients without HO. Patients with FO and a vertical dimension of ≥ 2.5 mm were more likely to develop HO (55.6%) than patients with a vertical FO dimension of less than 2.5 mm (34.7%, OR = 2.35 p = 0.047). A weak correlation between the vertical and horizontal size of FO and the severity of HO was observed.

CONCLUSION

Radiographic evidence of asymptomatic FO is a potential risk factor for the development of HO following THA and may be used as a simple diagnostic tool to pre-operatively identify patients at risk for post-operative HO. This association has not been previously described and further research to confirm the present findings and to justify additional prophylactic treatment in these patients is warranted.

Localized low-dose rhBMP-2 is effective at promoting bone regeneration in mandibular segmental defects

At least 26% of recent battlefield injuries are to the craniomaxillofacial (CMF) region. Recombinant human bone morphogenetic protein 2 (rhBMP-2) is used to treat CMF open fractures, but several complications have been associated with its use. This study tested the efficacy and safety of a lower (30% recommended) dose of rhBMP-2 to treat mandibular fractures. rhBMP-2 delivered via a polyurethane (PUR) and hydroxyapatite/β-tricalcium phosphate (Mastergraft®) scaffold was evaluated in a 2 cm segmental mandibular defect in minipigs. Bone regeneration was analyzed at 4, 8, and 12 weeks postsurgery using clinical computed tomography (CT) and rhBMP-2, and inflammatory marker concentrations were analyzed in serum and surgery-site drain effluent. CT scans revealed that pigs treated with PUR-Mastergraft® + rhBMP-2 had complete bone bridging, while the negative control group showed incomplete bone-bridging (n = 6). Volumetric analysis of regenerated bone showed that the PUR-Mastergraft® + rhBMP-2 treatment generated significantly more bone than control by 4 weeks, a trend that continued through 12 weeks. Variations in inflammatory analytes were detected in drain effluent samples and saliva but not in serum, suggesting a localized healing response. Importantly, the rhBMP-2 group did not exhibit an excessive increase in inflammatory analytes compared to control. Treatment with low-dose rhBMP-2 increases bone regeneration capacity in pigs with mandibular continuity defects and restores bone quality. Negative complications from rhBMP-2, such as excessive inflammatory analyte levels, were not observed. Together, these results suggest that treatment with low-dose rhBMP-2 is efficacious and may improve safety when treating CMF open fractures. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 1491-1503, 2019.

Outcome after Surgical Management of Acetabular Fractures: A 7-Year Experience

Objective

To determine the functional and radiologic results of surgical treatment in patients with acetabular fractures.

Methods

This was a retrospective cross-sectional study. We retrospectively reviewed medical records of patients operatively treated acute acetabular fractures at a level I trauma center (Shahid Rajaee) and an orthopedic center (Shahid Chamran) both in southern Iran (Shiraz) with minimally 1 year follow up over a period of 7 years from April 2009 to March 2016. Functional and radiographic outcomes, and complication were considered as main outcomes.

Results

A total number of 79 patients completed the study. Fifty-five patients were operated through Kocher-Langenbeck approach, and 18 were operated through the standard ilioinguinal approach, and 6 patients were operated through the standard ilioinguinal approach combined with Kocher-Langenbeck approach. The mean follow-up of patients was 45.6 months. The average operative time was 162.4±78.5 min, and the median blood loss was 500 ml. Functional results were excellent in 41 patients (51.9%), good in 12 (15.2%), fair in 13 (16.5%), and poor in 13 patients (16.5%). Radiologic results were excellent in 27 cases (34.2%), good in 17 cases (21.5%), fair in 18 cases (22.8%), and poor in 16 (16.5%). Osteoarthritis of hip (60.8%) and AVN of head of femur (22.8%) were two most common complications. In addition, there wasn't any significant difference between surgical approaches regarding clinical and radiographic outcomes.

Conclusion

The operative treatment for acetabular fractures gives universally satisfactory results. Thereafter, this study provides evidence that ilioinguinal approach is a good choice for anterior fractures, Kocher-Langenbeck is a good choice for posteriors fractures, and combined approach may be a good choice in the management of acetabular fractures involving two columns.

Results of 167 consecutive cases of acetabular fractures using the Kocher-Langenbeck approach: a case series

Background

Acetabular fractures are quite challenging injuries for the orthopedic surgeon because of their low incidence and their deep and complex anatomy. The objective of this study was to evaluate surgeon-independent parameters that might influence radiographic outcome and early complication rates of high-energy acetabular fractures treated by open reduction and internal fixation via the Kocher-Langenbeck approach, the golden standard for posterior access.

Methods

One hundred sixty-seven consecutive patients (111 males and 56 females) with a mean age of 41.8 years and a mean follow-up period of 10 months were surgically treated by one experienced surgeon at a level I trauma center within 10 years. To quantify the radiographic outcome, the Matta, Brooker, and Epstein grades were used. Posttraumatic arthritis and avascular necrosis of the femoral head (defined as Helfet grades 3 or 4 and Ficat/Arlet stages 3 or 4, respectively) were evaluated. Furthermore, subgroup analyses according to fracture type, age, and gender were performed for each outcome measure and complication (infection, hemorrhagic shock, revision surgery, nerve damage, and need of a total hip arthroplasty).

Results

65 A1, 34 A2, 51 B1, and 17 B2 fractures were identified according to the AO/ASIF classification. Of all patients, reduction was rated anatomic in 63.5%, imperfect in 22.2%, and poor in 14.4%. Degenerative changes were observed in 49.7%; 37.9% were affected by heterotopic ossification, 21.6% by posttraumatic arthritis, and 5.4% by avascular necrosis of the femoral head. Fifteen percent were diagnosed with a nerve damage, and 4.8% sustained an infection. Total hip arthroplasty was performed in 10.2%. Revision surgery due to secondary loss of reduction, seroma/hematoma, and wound infection was indicated in 6.0%.

Conclusions

Fracture type, age, and gender are prognostic factors for the surgical outcome after ORIF of high-energy acetabular fractures.

Electronic supplementary material

The online version of this article (doi:10.1186/s13018-017-0563-6) contains supplementary material, which is available to authorized users.

Influence of surgical approach on heterotopic ossification after total hip arthroplasty - is minimal invasive better? A case control study

BACKGROUND

Heterotopic ossification (HO) is a well-known complication after total hip arthroplasty (THA). Recently, the trend is to operate THA minimally invasive being less traumatic than standard approaches and promising a faster return to activity. The purpose of the study was to investigate if minimal invasive surgery (MIS), leads also to less HO after THA.

METHODS

This retrospective study included 134 consecutive patients undergoing THA. In 42 (31.3%) patients a standard modified anterolateral (STD-Watson-Jones), in 28 (20.9%) patients a standard transgluteal Bauer approach (STD-Bauer), in 39 (29.1%) a MIS direct anterior approach (AMIS) and in 25 (18.7%) patients a MIS anterolateral (MIS-AL) approach was used. Standard preoperative anterior-posterior and lateral radiographs were assessed for occurrence of HO. HO was classified according to Brooker. In addition, short- and long-term adverse events were noted. Data was statistically analyzed using Chi-square tests, analysis of variance, multivariate data analysis and Pearson's correlation (p < 0.05).

RESULTS

Overall, HO was found in 38 caucasian patients (28.4%) after THA. The STD-Watson-Jones group showed the highest HO rate (45.2% n = 19) with a significant difference to the AMIS (23.1% n = 9) and STD-Bauer approach (14.3% n = 4). No statistical difference was found to the MIS-AL approach (24.0% n = 6). Postoperative complications did not differ significantly except for a higher incidence of Trendelenburg`s sign in STD-Bauer.

CONCLUSIONS

The rate and degree of HO after THA were significantly different with regards to the surgical approach. The standard modified anterolateral approach resulted in the highest HO rate, however, MIS approaches showed higher HO rates than the STD-Bauer.

Does Prior Surgery for Femoroacetabular Impingement Compromise Hip Arthroplasty Outcomes?

BACKGROUND

Open and arthroscopic approaches have been described to address femoroacetabular impingement (FAI). Despite good outcomes, there is a subset of patients who subsequently require total hip arthroplasty (THA). However, there is a paucity of data on the outcomes of THA after surgery for FAI. The purpose of this study was to determine whether clinical outcomes of THA are affected by prior open or arthroscopic treatment of FAI.

METHODS

This case-matched retrospective review included 23 patients (24 hips) that underwent THA after previous surgery for FAI (14 arthroscopic and 10 open) and compared them to 24 matched controls with no history of prior surgery on the operative hip. The controls were matched for age, sex, surgical approach, implants used, and preoperative modified Harris hip score (mHHS) did not differ between groups. The primary outcome measure was the mHHS. Operative time, blood loss, and the presence of heterotopic ossification after THA were also compared between groups.

RESULTS

There was no significant difference in mean mHHS between the FAI treatment group 92.9 ± 12.7 and controls 95.2 ± 6.6 (P = .43) at a mean follow-up after THA of 33 (24-70) months. Increased operative times were noted for THA after surgical hip dislocation (SHD; mean 109.3 ± 29.8) compared to controls (mean 88.0 ± 24.2; P < .05). There was no significant difference in blood loss between groups. The occurrence of heterotopic ossification was significantly higher after SHD compared to controls (P < .05).

CONCLUSIONS

Clinical outcomes after THA are not affected by prior open or arthroscopic procedures for FAI. However, increased operative times and an increased risk of heterotopic ossification were noted after SHD.

Clinical and radiological analysis of Bryan cervical disc arthroplasty: eight-year follow-up results compared with anterior cervical discectomy and fusion

PURPOSE

Bryan cervical disc arthroplasty has been reported with satisfactory short- and medium-term clinical results. However, the long-term clinical and radiographic outcomes are seldom reported. The purpose of this study was to compare the eight-year follow-up results in patients who underwent Bryan disc arthroplasty with patients received ACDF, and assess the incidence of heterotopic ossification (HO) and its effect on clinical outcome and mobility of the device.

METHODS

Thirty-one patients underwent Bryan disc arthroplasty, and 35 patients underwent ACDF were included in the study. The Japanese Orthopedic Association (JOA) scores, neck disability index (NDI), visual analogue scale (VAS) of neck and arm pain, and the radiographs were used to evaluate the outcomes. The heterotopic ossification (HO) was determined by CT scan and was classified into three subgroups to compare the related effect. Adjacent segment degeneration (ASD) was also observed.

RESULTS

At final follow-up, there were no significant differences in JOA scores between two groups, but the improvement in NDI and neck or arm VAS were significantly greater in the Bryan disc cohort. The range of motion at the index level was 7.0° in Bryan group, while 100 % bone fusion were achieved in ACDF group. HO was observed in 18 (51.4 %) levels. There were more restricted movement of the prosthesis and slight higher rate of axial pain in patients with severe-HO (grade III and IV). Fourteen (28.6 %) levels developed ASD in Bryan group, which was significantly lower than that (58.6 %) in ACDF group.

CONCLUSIONS

At eight year follow-up, the clinical and radiographic outcomes of Bryan cervical disc arthroplasty compared favorably to those of ACDF. It avoided accelerated adjacent segment degeneration by preserving motion. However, severe HO restricted the ROM of the index levels and maybe associated with post-operative axial pain.

Comparative clinical study of the prophylaxis of heterotopic ossifications after total hip arthroplasty using etoricoxib or diclofenac

PURPOSE

This study investigated whether etoricoxib (COX-II blocker) has a superior efficacy of preventing heterotopic ossification (HO) after total hip arthroplasty (THA) compared to diclofenac (non-selective NSAID).

METHODS

One hundred patients were included (50 in each group) in this single centre, prospective, double-blinded, randomized, controlled trial. Etoricoxib (90 mg) was administered once and diclofenac (75 mg) twice per day for a perioperative period of nine days. The incidence of HO was evaluated on radiographs of the pelvis six months after surgery.

RESULTS

Eighty nine of 100 (89 %) patients could be analysed. The overall HO incidence was 37.8 %. There was no significant difference between both study groups. Twelve patients (27.3 %) of the DIC group and 13 patients (28.9 %) of the ETO group showed Brooker grade I ossifications. Five patients (11.4 %) of the DIC and four patients of the ETO (8.9 %) group showed grade II HO formations. No class III or IV HO formations occured in both groups. Ad hoc analysis detected a negative correlation between HO incidence and limited abduction and internal rotation of the hip.

CONCLUSIONS

Etoricoxib and diclofenac are equally effective for oral HO prophylaxis after primary cementless THA when given for nine peri-operative days to ensure a full recovery and high patient satisfaction.

Acute revision hip arthroplasty: a previously unrecognized risk factor for heterotopic ossification

BACKGROUND

The aim of this retrospective review was to determine the incidence and severity of heterotrophic ossification (HO) following acute revision total hip arthroplasty (THA), and whether this represents a significant risk factor for HO that should be treated prophylactically.

MATERIALS AND METHODS

A total of seven patients (three men and four women) with a mean age of 55 years (39-70 years) who underwent a reoperation of their THA for any reason that required a hip arthrotomy within 3 weeks of their primary or revision THA were included, with a mean follow-up of 8.8 years (2-12 years). All patients were evaluated radiographically for any evidence of HO and clinically using the Harris Hip Score.

RESULTS

All seven hips (100 %) developed HO, with 71 % being severe (Brooker III and IV HO). One hip (14 %) developed Brooker IV HO, four hips (57 %) developed Brooker III HO, and two hips (29 %) developed Brooker II HO. The patient's range of motion varied, but was very limited in three patients. Three patients (42.8 %) were not satisfied with their surgery; one patient had Brooker IV HO, and two patients had Brooker III HO.

CONCLUSION

Acute reoperation after primary or revision THA is a significant risk factor for the development of extensive HO, which requires prophylactic treatment.

The impact of race on the development of severe heterotopic ossification following acetabular fracture surgery

OBJECTIVES

To determine the association between race on severe heterotopic ossification (HO) following acetabular fracture surgery.

DESIGN

Retrospective case control study.

SETTING

Level I university trauma centre.

METHODS

Two hundred and fifty-three patients who were surgically treated for acetabular fractures were retrospectively evaluated. Postoperative radiographs were evaluated for HO by a blinded musculoskeletal radiologist, and classified based on a modified Brooker classification.

RESULTS

Of the 253 patients that met inclusion and exclusion criteria, 175 (69%) were male and 78 (31%) were female. One hundred and fifty-four (61%) patients were Caucasian, and 99 (39%) were African American (AA). Fifty-five (21%) patients developed severe HO. Of those who developed severe HO, 25 were Caucasian (45%), 30 were African American (55%). Forty-one patients (75%) with severe HO were male, and 14 (25%) were female. No statistical differences (p>0.05) were found between groups in terms of age, days to surgery, GCS at presentation, surgical approach, perioperative HO prophylaxis, or AO/OTA fracture classification. The patient population was then stratified by race, gender, and race/gender. AA were more likely than Caucasians to develop severe HO (odds ratio [OR], 2.24; confidence interval [CI], 1.22-4.11). When gender was considered independent of race, no statistical differences (p>0.05) were observed (OR, 1.40; CI, 0.71-2.75). AA males were much more likely to develop severe HO when compared to Caucasian females (OR, 4.4; CI, 1.38-14.06).

CONCLUSION

Race is associated with different rates of severe HO formation following acetabular fracture surgery. AA patients are significantly more likely to develop severe HO following acetabular fracture surgery when compared to Caucasian patients.

Clinical significance of heterotopic ossification after metal-on-metal total hip resurfacing

Few studies about how heterotopic ossification (HO) affects functional outcome after metal-on-metal total hip resurfacing (MOMHR) have been reported. The purpose of this study was to evaluate the incidence and clinical significance of HO after MOMHR. We retrospectively reviewed 122 consecutive patients, who underwent MOMHR from June 2006 to October 2008, with adequate follow-up information. All patients had four weeks of aspirin (325 mg twice a day) for DVT prophylaxis and two weeks of celecoxib (400 mg once a day) for pain control. All data were collected prospectively including radiographs and functional scores preoperatively, at three months and at one year postoperatively. An independent musculoskeletal radiologist, using the Brooker classification, reviewed radiographs. Unbalanced ANOVA analyses were performed to evaluate the effect of HO on outcome. The overall incidence of HO at three months was 62.1% (grade 1: 39.8%, grade 2: 20.4%, grade 3: 1.9%) and 75% at one year (grade 1: 41.7%, grade 2: 27.8%, grade 3: 5.5%). There were no significant differences in the functional status scores among Brooker grade 0 to 3 groups at three months and one year follow-up. The incidence of HO after MOMHR was 62.1% at three months and 75% at one year despite a post-operative regimen of aspirin and celecoxib. We found no evidence that predominantly Brooker grade 1 or 2 HO affected the clinical outcome at three months or one year when compared across all Brooker classes of patients.

The Effect of NSAID Prophylaxis and Operative Variables on Heterotopic Ossification After Hip Arthroscopy

BACKGROUND

Heterotopic ossification (HO) is a known complication of hip arthroscopy. Little is known about the factors that lead to HO after hip arthroscopy.

PURPOSE

The aim of this study was to evaluate the effect of nonsteroidal anti-inflammatory drugs (NSAIDs) and other operative variables on the development of HO.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

A total of 357 consecutive cases of hip arthroscopy were retrospectively reviewed over a 3-year period. Routine NSAID prophylaxis was not performed for the first 117 cases. Prophylaxis with naproxen for 3 weeks was then routinely prescribed for the remaining 240 cases. Complete follow-up was available for 288 of the original 357 cases. The presence of HO and its characteristics were recorded for each patient, along with baseline demographic and surgical variables. Odds ratios and logistic regression were used to identify causal factors for HO.

RESULTS

The incidence of HO in cases in which the patient did not receive NSAID prophylaxis was 25.0% (23/92) versus 5.6% (11/196) of cases in which the patient received NSAIDs. Patients who received no NSAID prophylaxis were 13.6 times more likely to develop HO postoperatively (95% confidence interval, 2.44-75.5; P = .003). Comparing just mixed-type femoroacetabular impingement resections, patients who received no NSAID prophylaxis were 16.6 times more likely to develop HO postoperatively (95% confidence interval, 2.2-126.0; P = .006). Multivariate logistic regression identified the performance of a mixed-type femoroacetabular impingement resection (P = .011) and the absence of NSAID prophylaxis (P = .003) as predictors of HO development. The majority of HO cases (29/34) occurred in patients with mixed-type femoroacetabular impingement who had both osteochondroplasty and acetabuloplasty. Complications of NSAID therapy in this study population included acute renal failure, hematochezia from acute colitis, and gastritis.

CONCLUSION

Routine NSAID prophylaxis reduces but does not eliminate the incidence of HO in patients undergoing hip arthroscopy. Heterotopic ossification was more likely to develop in patients undergoing acetabuloplasty along with osteochondroplasty and in those who did not receive prophylactic postoperative NSAIDs. Side effects from the investigated NSAID regimen can be serious and should be weighed against the potential benefits in preventing the formation of HO.

Incidence of heterotopic ossification after surface and conventional total hip arthroplasty: a comparative study using anterolateral approach and indomethacin prophylaxis

The incidence and severity of heterotopic ossification (HO) in two homogeneous groups of patients that received surface replacement arthroplasty (SRA) and conventional total hip arthroplasty (THA) were evaluated retrospectively. Thirty-nine patients undergoing 42 hip resurfacing procedures and 41 primary cementless THAs through an anterolateral approach received a 10-day course of 150 mg/die of indomethacin postoperatively. The median surgical time was 190 minutes and 156 minutes, respectively (P < 0.003). At a minimum 1-year followup, the development of HO was assessed on standard X-ray using Brooker grading. Ectopic bone formation was detected in five cases (11.9%, two Brooker grade I and three grade II) in the SRA group and in 14 hips (34.1%, 12 grade I and two grade II) treated with conventional THA, but the difference was not significant (P < 0.11). No clinically relevant periprosthetic ossification (Brooker III or IV) occurred in both groups. Although the difference was not statistically significant, the incidence of HO after SRA was lower than conventional THA. More extensive soft tissue trauma, bone debris, and longer operative time in hip resurfacing are not likely to be absolute risk factors for HO. Further investigations including larger patient populations are needed to confirm these findings.

WITHDRAWN: Non-steroidal anti-inflammatory drugs for preventing heterotopic bone formation after hip arthroplasty

BACKGROUND

Heterotopic bone formation (HBF) in the soft tissues surrounding the hip joint is a frequent complication of hip surgery. Non-steroidal anti-inflammatory drugs (NSAIDs) administered in the immediate perioperative period reduce the risk of HBF. However, the magnitude of the effect on HBF, and the effects on other associated outcomes, such as pain and physical function, are uncertain.

OBJECTIVES

To determine the effects of perioperative NSAID therapy versus control on the risk of HBF and other outcomes in patients undergoing hip arthroplasty.

SEARCH METHODS

We searched the Cochrane Bone, Joint and Muscle Trauma Group specialised register (October 2002), the Cochrane Central Register of Controlled Trials (The Cochrane Library issue 3, 2002), MEDLINE (1966 to October 2002), EMBASE (1988 to 2002 Week 43), CURRENT CONTENTS (1993 Week 27 to 2002 Week 44) and reference lists of articles. We also contacted trialists and drug manufacturers.

SELECTION CRITERIA

All trials which enrolled patients scheduled to undergo hip arthroplasty with random or quasi-random allocation to perioperative NSAID or control and that recorded post-operative radiographically determined HBF. The primary outcome was post-operative radiographic HBF. Secondary outcomes were pain, function (including range of motion), gastro-intestinal and other bleeding complications, and other causes of major morbidity or mortality.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed methodological quality and extracted data. All analyses were conducted on dichotomised outcomes.

MAIN RESULTS

Sixteen randomised and two quasi-randomised trials involving a total of 4,763 patients were included. Overall, in 17 trials that examined the effects of medium to high doses of NSAIDs, there was a reduced risk of developing HBF after hip surgery (59% reduction, 95% confidence interval 54% to 64% reduction). In contrast, one large trial examining low-dose aspirin, demonstrated no effect on the risk of HBF (2% reduction, 95% confidence interval 15% reduction to 12% increase). There was strong evidence of differences in the size of the treatment effects observed between the trials examining medium to high doses of NSAIDs, but reasons were not clearly identified.There was a non-significant one third increased risk of gastro-intestinal side effects among patients assigned NSAIDs (29% increase, 95% confidence interval 0% to 76% increase). Most of this increase was due to an increased risk of minor gastro-intestinal complications. Data on the late post-operative outcomes of pain, impaired physical function and range of joint movement were few and no formal overviews of the effects of NSAIDs on these outcomes were possible.

AUTHORS' CONCLUSIONS

Perioperative NSAIDs, apart from low dose aspirin, appear to produce between a one half and two thirds reduction in the risk of HBF. With routine use, such agents may be able to prevent 15-20 cases of HBF among every 100 total hip replacements performed. However, while medium to high doses of perioperative NSAIDs clearly produce a substantial reduction in the incidence of radiographic HBF, there remains some uncertainty about short-term side effects of treatment and substantial uncertainty about effects on long-term clinical outcomes such as chronic pain and impaired physical function. The net effect of routine HBF prophylaxis with NSAIDs requires formal assessment in a randomised trial designed to determine the balance of benefits and risks for all outcomes.

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.

Adherence to routine use of pharmacological prophylaxis of heterotopic ossification after total hip arthroplasty: results from an Italian multicenter, prospective, observational survey

BACKGROUND

In spite of the proven efficacy of pharmacological prophylaxis of heterotopic ossification following total hip arthroplasty, its routine use is still debated, and no data are available regarding the adherence to its administration in clinical practice.

MATERIALS AND METHODS

In this prospective, observational, multicenter study, 480 consecutive patients operated on for primary total hip arthroplasty during the year 2009 were followed radiographically for 12 months after surgery in order to assess the incidence of periprosthetic heterotopic ossification. Surgeons were free to choose whether to administer pharmacological prophylaxis, and were asked to keep a record of the duration of the prophylaxis (if used) or the reasons for not using it. To facilitate the statistical analysis, all of the participating centers agreed to use only one drug (celecoxib) that had already proven to be effective.

RESULTS

368 patients were administered celecoxib and 112 patients did not receive any prophylaxis. Reported reasons for not administering celecoxib prophylaxis were the surgeon's opinion that prophylaxis was not needed on a routine basis (84/112 patients, 75%), previous history of gastrointestinal bleeding (17.8%), and concomitant cardiorenal pathologies (7.1%). The overall incidence of heterotopic ossification in the celecoxib-treated patients was 23% (no cases of Brooker grade 3 or 4 ossifications), compared to 55% in the untreated patients (Brooker grade 3 and 4: 8.9%). Multivariate analysis showed that celecoxib prophylaxis was the single most important variable when predicting the occurrence of heterotopic ossification.

CONCLUSIONS

This study confirms the efficacy and tolerability of celecoxib for the prophylaxis of heterotopic ossification after total hip arthroplasty, and shows how the surgeon's belief that routine prevention is not required still plays an important role in the determination of this complication, together with the fear of possible unwanted side effects.

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.

Does a plastic drape reduce incidence of heterotopic ossification after hip resurfacing?

BACKGROUND

High rates of heterotopic ossification have been associated with hip resurfacing as compared to THA. Bone debris from femoral head reamings is cited as one of the risk factors linked to increased rates of heterotopic ossification.

QUESTIONS/PURPOSES

We therefore asked whether (1) the incidence of heterotopic ossification differed with and without the use of a plastic drape used to collect bone debris and (2) any of a number of variables (age, gender, diagnosis, previous hip surgery, operative time, and blood loss) related to the occurrence of HO.

METHODS

We retrospectively reviewed 136 hip resurfacings performed using one of two techniques: Group 1 contained 64 hip resurfacings performed using a sterile drape around the femoral neck while reaming the femoral head to collect bone debris; Group 2 contained 72 hip resurfacings carried out with manually removing bone debris and utilizing a pulse lavage. Data were collected with respect to diagnosis, gender, previous surgery, postoperative complications, operative time, and blood loss to rule out confounding variables. The amount of heterotopic ossification was measured radiographically in hips after undergoing resurfacing arthroplasty. The minimum followup was 6 months (mean, 15 months; range, 6-27 months).

RESULTS

No patient had heterotopic ossification of clinical importance and none had resection of the heterotopic ossification. Group 1 had a lower overall incidence of minor heterotopic ossification (32%) than Group 2 (58%). Risk factors linked to heterotopic ossification include male gender and operative time.

CONCLUSIONS

The use of a plastic drape to collect bone debris from femoral head reamings decreased the incidence of heterotopic ossification in resurfacing arthroplasty of the hip.

Complications after metal-on-metal hip resurfacing arthroplasty

This article determines the incidence and cause of the complications commonly associated with metal-on-metal hip resurfacing implants and the proposed methods to prevent these complications. The literature available in PubMed was reviewed. Complication rates after hip resurfacing are low, and the procedure has shown both safety and efficacy in the hands of surgeons trained in specialized centers. Proper surgical technique can further reduce the incidence of femoral neck fracture, component loosening, and abnormal wear of the prosthesis. A more systematic detection of adverse local tissue reactions is needed to provide accurate assessments of their prevalence.

The predictive power of preoperative hip range of motion for the development of heterotopic ossification

Postoperative development of heterotopic ossification can compromise the success of total hip arthroplasty (THA). Heterotopic ossification has been associated with decreased postoperative hip range of motion (ROM), potentially leading to poor patient satisfaction with outcome. Many risk factors predisposing to heterotopic ossification have been discussed in the literature, including sex, age, operative time, surgical approach, and preoperative function. The goal of this study was to examine if preoperative ROM is a risk factor for the development of severe heterotopic ossification after THA, and the impact of severe heterotopic ossification formation on the gain in ROM following THA. In a retrospective study of a single surgeon's 20-year experience, all patients who developed type III heterotopic ossification after THA were evaluated for hip ROM preoperatively and at 1-year follow-up. Total ROM was classified according to the modified Merle d'Aubigne score, and Harris Hip Scores were calculated. A statistically significant difference was found in preoperative external rotation in the study group compared to the control group (P<.001). At 1 year postoperatively, hip ROM differences were significant in external rotation (P<.001), internal rotation (P<.001), and abduction (P<.05). The modified Merle d'Aubigne score was significantly different between the groups (P<.001). Although many factors have been shown to influence the development of heterotopic ossification following THA, we found that a decrease in preoperative external rotation may point to an increased risk. Surgeons should consider this data when considering the use of prophylactic treatment to avoid the development of heterotopic ossification.

Circulating osteogenic precursor cells

Circulating osteogenic precursor (COP) cells are blood-borne cells that express a variety of osteoblastic markers and are able to form bone in vivo. Strong evidence suggests that COP cells are derived from bone marrow and are of hematopoietic origin. The study of COP cells has been limited by several factors, including the difficulty in establishing long-term cultures and lack of a standardized protocol for their isolation and identification. However, experimental evidence supports that COP cells seed sites of injury and inflammation in response to homing signals and are involved in processes of pubertal growth, fracture, and diverse conditions of heterotopic bone formation. The role of COP cells in physiologic and pathophysiologic conditions of de novo bone formation suggests that they may serve as future targets for diagnostic measurements and therapeutic interventions.

Clinical significance of the heterotopic ossification after total hip arthroplasty

Heterotopic ossification represents one of the most frequent complications following any type of hip arthroplasty. However, disagreement exists regarding the clinical significance of heterotopic ossification after total hip arthroplasty (THA). This study evaluated the effect of different grades of heterotopic ossification on range of hip motion, pain, and the clinical outcome in patients after THA. The study included 198 patients with primary THA because of unilateral hip osteoarthritis, followed for a minimum of 1 year after THA. Diagnosis and classification of heterotopic ossification according to Brooker was achieved on anteroposterior radiograph of the hips 1 year postoperatively. The clinical outcome was assessed at 1-year follow-up with the use of the Harris hip score. Pain was assessed as the pain component of the Harris hip score. Hip range of motion was measured passively in the lying position with a goniometer and recorded in degrees according to the method suggested by the American Academy of Orthopaedic Surgeons 1988. The incidence of heterotopic ossification was 47% and the incidence of severe ossification was 11%. The severe heterotopic ossification significantly reduced clinical outcome, overall range of hip motion and certain components such as flexion, abduction and external rotation, but had no significant effect on pain, while the lower degree of ossification did not significantly influence the clinical outcome, hip motion and pain. This study has shown that only severe heterotopic ossification is of clinical significance.

Circulating osteogenic precursor cells in heterotopic bone formation

Cells with osteogenic potential can be found in a variety of tissues. Here we show that circulating osteogenic precursor (COP) cells, a bone marrow-derived type I collagen+/CD45+ subpopulation of mononuclear adherent cells, are present in early preosseous fibroproliferative lesions in patients with fibrodysplasia ossificans progressiva (FOP) and nucleate heterotopic ossification (HO) in a murine in vivo implantation assay. Blood samples from patients with FOP with active episodes of HO contain significantly higher numbers of clonally derived COP cell colonies than patients with stable disease or unaffected individuals. The highest level of COP cells was found in a patient just before the clinical onset of an HO exacerbation. Our studies show that even COP cells derived from an unaffected individual can contribute to HO in genetically susceptible host tissue. The possibility that circulating, hematopoietic-derived cells with osteogenic potential can seed inflammatory sites has tremendous implications and, to our knowledge, represents the first example of their involvement in clinical HO. Thus, bone formation is not limited to cells of the mesenchymal lineage, and circulating cells of hematopoietic origin can also serve as osteogenic precursors at remote sites of tissue inflammation.

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.

Heterotopic ossification after surface replacement arthroplasty and total hip arthroplasty: a randomized study

With a randomized clinical trial, we compared the incidence and severity of heterotopic ossification in cohorts of patients who have undergone either surface replacement arthroplasty or total hip arthroplasty at a minimum follow-up of 1 year. Surface replacement arthroplasty group had a significantly higher rate of severe heterotopic ossification (Brooker grades 3-4) than the total hip arthroplasty group, 12.6% (13/103) vs 2.1% (2/97) respectively (P = .02). Grade 4 heterotopic ossification was observed (4.9%, 5/103) exclusively in the surface replacement arthroplasty group. Patients with severe heterotopic ossification had significantly inferior functional outcome scores. Surgeons offering surface replacement must be aware of this risk and use meticulous surgical technique and consider routine prophylaxis against heterotopic ossification.

Incidence of heterotopic ossification after hip resurfacing

BACKGROUND

Heterotopic ossification has been noted around total hip arthoplasty in numerous studies. With hip resurfacing growing in popularity, we have prospectively evaluated the incidence in a cohort undergoing hip resurfacing.

METHODS

Two hundred and twenty consecutive hip-resurfacing procedures were prospectively reviewed at a minimum of 2 years follow up to assess the incidence of heterotopic ossification and its effect on function and clinical outcome. We also reviewed the preoperative diagnosis, age, sex and previous surgery.

RESULTS

The overall percentage of heterotopic ossification was 58.63%. The incidence of Brooker 1 was 37.27%, Brooker 2 was 13.18% and Brooker 3 was 8.18%. Male osteoarthritis had the highest incidence of heterotopic bone formation (HBF). Three men underwent excision of heterotopic bone, two for pain and stiffness and one for decreased range of movement. Both anteroposterior and lateral radiographs were reviewed for evidence of HBF. In all, 12.7% had no evidence of HBF in the first view but clearly had in the second view.

CONCLUSIONS

Overall, we found no evidence that HBF affected the clinical or functional outcome of the hip resurfacing at a mean of 3 years follow up. However, in light of the high incidence of HBF seen in a yet unproven long-term prosthesis, we conclude that the Cochrane database recommendations with regard to prophylaxis should be implemented.

Celecoxib versus ibuprofen in the prevention of heterotopic ossification following total hip replacement: a prospective randomised trial

We examined whether a selective cyclooxygenase-2 (COX-2) inhibitor (celecoxib) was as effective as a non-selective inhibitor (ibuprofen) for the prevention of heterotopic ossification following total hip replacement. A total of 250 patients were randomised to receive celecoxib (200 mg b/d) or ibuprofen (400 mg t.d.s) for ten days after surgery. Anteroposterior radiographs of the pelvis were examined for heterotopic ossification three months after surgery. Of the 250 patients, 240 were available for assessment. Heterotopic ossification was more common in the ibuprofen group (none 40.7% (50), Brooker class I 46.3% (57), classes II and III 13.0% (16)) than in the celecoxib group (none 59.0% (69), Brooker class I 35.9% (42), classes II and III 5.1% (6), p=0.002). Celecoxib was more effective than ibuprofen in preventing heterotopic bone formation after total hip replacement.

Safety and efficacy of routine postoperative ibuprofen for pain and disability related to ectopic bone formation after hip replacement surgery (HIPAID): randomised controlled trial

OBJECTIVES

To determine the benefits and risks of a non-steroidal anti-inflammatory drug (NSAID) as prophylaxis for ectopic bone formation in patients undergoing total hip replacement (or revision) surgery.

DESIGN

Double blind randomised placebo controlled clinical trial, stratified by treatment site and surgery (primary or revision).

SETTING

20 orthopaedic surgery centres in Australia and New Zealand.

PARTICIPANTS

902 patients undergoing elective primary or revision total hip replacement surgery.

INTERVENTION

14 days' treatment with ibuprofen (1200 mg daily) or matching placebo started within 24 hours of surgery.

MAIN OUTCOME MEASURES

Changes in self reported hip pain and physical function 6 to 12 months after surgery (Western Ontario and McMaster University Arthritis index).

RESULTS

There were no significant differences between the groups for improvements in hip pain (mean difference -0.1, 95% confidence interval -0.4 to 0.2, P = 0.6) or physical function (-0.1, -0.4 to 0.2, P = 0.5), despite a decreased risk of ectopic bone formation (relative risk 0.69, 0.56 to 0.83) associated with ibuprofen. There was a significantly increased risk of major bleeding complications in the ibuprofen group during the admission period (2.09, 1.00 to 4.39).

CONCLUSIONS

These data do not support the use of routine prophylaxis with NSAIDs in patients undergoing total hip replacement surgery.

TRIAL REGISTRATION

NCT00145730.

Clinical significance of heterotopic ossification in cervical disc replacement: a prospective multicenter clinical trial

OBJECTIVE

Heterotopic ossification (HO) is a well-known complication in joint replacements, but its occurrence and clinical effect on cervical artificial discs has not yet been studied. The purpose of this study was to investigate the incidence of HO in cervical disc replacement, to identify any associated risk factors for HO, and to examine the relationship of HO with clinical outcomes.

METHODS

The patient data for this observational study were obtained from the original Bryan Disc Study by the European Consortium. Occurrence of HO was defined by the McAfee classification on the cervical lateral x-rays at 12 months after surgery. Secondary outcome measurements included Odom's criteria and the Medical Outcomes Study Short-Form 36-Item Health Survey.

RESULTS

Sixteen (17.8%) of the 90 studied patients experienced HO, and 6 (6.7%) of these patients experienced Grade 3 and 4 HO. Ten patients' (11%) artificial discs were shown to have movement of less than 2 degrees on flexion and extension cervical x-ray at 12 months, with 4 of these patients having HO of Grade 3 or 4. Male sex (chi2 = 4.1; P = 0.0407) and older patients (P = 0.023; odds ratio = 1.10; 95% confidence interval = 1.01-1.19) were associated with development of HO.

CONCLUSION

There is a strong association of the occurrence of HO with subsequent loss of movement of the implanted cervical artificial disc. We have found that sex and age are two possible risk factors in the development of HO after cervical disc replacement.

Amino-bisphosphonates in heterotopic ossification: first experience in five consecutive cases

STUDY DESIGN

Retrospective, observational study in five consecutive cases.

OBJECTIVES

The management of heterotopic ossification (HO), a frequent complication after spinal cord injury (SCI) and after orthopaedic surgery, is a therapeutic challenge with high recurrence rates of over 50%. Conflicting data were reported for Etidronate. The use of the more potent new generation of amino-bisphosphonates has been put forward in different inflammatory, dysmorphogenic bone disease. In order to try and halt the underlying dysfunctional bone metabolism we have studied the action of pamidronate in five consecutive high-risk patients with established HO of different etiology undergoing surgical removal.

SETTING

University Hospital of Basel, Switzerland, Division of Endocrinology, Diabetology and Clinical Nutrition and the Department of Orthopedic Surgery.

METHODS

In all five patients, ranging from 47 to 68 years of age, we used continuous pamidronate infusions perioperatively at a dosage of 120 mg in the first 12 h and subsequent reduction to 75-60-30-15 mg/12 h over a period of 10-14 days.

RESULTS

None of these patients showed clinical, radiographical and laboratory signs of HO recurrence or new forming HO in the follow-up 5-54 month after surgery. Potential side effects of high-dose bisphosphonate therapy such as osteoporosis and osteomalacia were not reported in any case.

CONCLUSION

We postulate that pamidronate might have pronounced beneficial effects in high-risk patients with established HO undergoing excision surgery. Since the therapeutic window of amino-bisphosphonates has not yet been defined and the minimal necessary doses for preventing new HO are unknown, further studies are encouraged to confirm our findings and to identify the necessary dosage and duration of treatment and to pinpoint, which patients will benefit most from this treatment.

Clinical Significance of Heterotopic Ossification in Cervical Disc Replacement: A Prospective Multicenter Clinical Trial

OBJECTIVE:

Heterotopic ossification (HO) is a well-known complication in joint replacements, but its occurrence and clinical effect on cervical artificial discs has not yet been studied. The purpose of this study was to investigate the incidence of HO in cervical disc replacement, to identify any associated risk factors for HO, and to examine the relationship of HO with clinical outcomes.

METHODS:

The patient data for this observational study were obtained from the original Bryan Disc Study by the European Consortium. Occurrence of HO was defined by the McAfee classification on the cervical lateral x-rays at 12 months after surgery. Secondary outcome measurements included Odom's criteria and the Medical Outcomes Study Short-Form 36-Item Health Survey.

RESULTS:

Sixteen (17.8%) of the 90 studied patients experienced HO, and 6 (6.7%) of these patients experienced Grade 3 and 4 HO. Ten patients' (11%) artificial discs were shown to have movement of less than 2 degrees on flexion and extension cervical x-ray at 12 months, with 4 of these patients having HO of Grade 3 or 4. Male sex (χ2 = 4.1; P = 0.0407) and older patients (P = 0.023; odds ratio = 1.10; 95% confidence interval = 1.01–1.19) were associated with development of HO.

CONCLUSION:

There is a strong association of the occurrence of HO with subsequent loss of movement of the implanted cervical artificial disc. We have found that sex and age are two possible risk factors in the development of HO after cervical disc replacement.

Non-steroidal anti-inflammatory drugs for preventing heterotopic bone formation after hip arthroplasty

BACKGROUND

Heterotopic bone formation (HBF) in the soft tissues surrounding the hip joint is a frequent complication of hip surgery. Non-steroidal anti-inflammatory drugs (NSAIDs) administered in the immediate perioperative period reduce the risk of HBF. However, the magnitude of the effect on HBF, and the effects on other associated outcomes, such as pain and physical function, are uncertain.

OBJECTIVES

To determine the effects of perioperative NSAID therapy versus control on the risk of HBF and other outcomes in patients undergoing hip arthroplasty.

SEARCH STRATEGY

We searched the Cochrane Musculoskeletal Injuries Group specialised register (October 2002), the Cochrane Central Register of Controlled Trials (The Cochrane Library issue 3, 2002), MEDLINE (1966 to October 2002), EMBASE (1988 to 2002 Week 43), CURRENT CONTENTS (1993 Week 27 to 2002 Week 44) and reference lists of articles. We also contacted trialists and drug manufacturers.

SELECTION CRITERIA

All trials which enrolled patients scheduled to undergo hip arthroplasty with random or quasi-random allocation to perioperative NSAID or control and that recorded post-operative radiographically determined HBF. The primary outcome was post-operative radiographic HBF. Secondary outcomes were pain, function (including range of motion), gastro-intestinal and other bleeding complications, and other causes of major morbidity or mortality.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed methodological quality and extracted data. All analyses were conducted on dichotomised outcomes.

MAIN RESULTS

Sixteen randomised and two quasi-randomised trials involving a total of 4,763 patients were included. Overall, in 17 trials that examined the effects of medium to high doses of NSAIDs, there was a reduced risk of developing HBF after hip surgery (59% reduction, 95% confidence interval 54% to 64% reduction). In contrast, one large trial examining low-dose aspirin, demonstrated no effect on the risk of HBF (2% reduction, 95% confidence interval 15% reduction to 12% increase). There was strong evidence of differences in the size of the treatment effects observed between the trials examining medium to high doses of NSAIDs, but reasons were not clearly identified. There was a non-significant one third increased risk of gastro-intestinal side effects among patients assigned NSAIDs (29% increase, 95% confidence interval 0% to 76% increase). Most of this increase was due to an increased risk of minor gastro-intestinal complications. Data on the late post-operative outcomes of pain, impaired physical function and range of joint movement were few and no formal overviews of the effects of NSAIDs on these outcomes were possible.

REVIEWERS' CONCLUSIONS

Perioperative NSAIDs, apart from low dose aspirin, appear to produce between a one half and two thirds reduction in the risk of HBF. With routine use, such agents may be able to prevent 15-20 cases of HBF among every 100 total hip replacements performed. However, while medium to high doses of perioperative NSAIDs clearly produce a substantial reduction in the incidence of radiographic HBF, there remains some uncertainty about short-term side effects of treatment and substantial uncertainty about effects on long-term clinical outcomes such as chronic pain and impaired physical function. The net effect of routine HBF prophylaxis with NSAIDs requires formal assessment in a randomised trial designed to determine the balance of benefits and risks for all outcomes.