Occurrence Of Heterotopic Ossification Research Articles

Clinical and Radiological Outcomes of Cervical Disc Arthroplasty in Patients with Modic Change.

Modic change (MC) is defined as abnormalities observed in the intervertebral disc subchondral and adjacent vertebral endplate subchondral bone changes. Most studies on MC were reported in the lumbar spine and associated with lower back pain. However, MC has been rarely reported in the cervical spine, let alone in those who underwent cervical disc replacement (CDR). This study aimed to focus on MC in the cervical spine and reveal clinical and radiological parameters, especially heterotopic ossification (HO), for patients who underwent CDR. Furthermore, we illustrated the association between MC and HO. We retrospectively reviewed patients who underwent CDA from January 2008 to December 2019. The Japanese Orthopaedic Association (JOA), Neck Disability Index (NDI), and Visual Analog Scale (VAS) scores were used to evaluate the clinical outcomes. Radiological evaluations were used to conclude the cervical alignment (CL) and range of motion (ROM) of C2-7, functional spinal unit angle (FSUA), shell angle (SA), FSU height, and HO. Univariate and multivariate logistic regressions were performed to identify the risk factors for HO. The Kaplan-Meier (K-M) method was used to analyze potential risk factors, and multivariate Cox regression was used to identify independent risk factors. A total of 139 patients were evaluated, with a mean follow-up time of 46.53 ± 26.60 months. Forty-nine patients were assigned to the MC group and 90 to the non-MC group. The incidence of MC was 35.3%, with type 2 being the most common. Clinical outcomes (JOA, NDI, VAS) showed no significant difference between the two groups. The differences in C2-7 ROM between the two groups were not significant, while the differences in SA ROM and FSUA ROM were significantly higher in the non-MC than in the MC group (p < 0.05). Besides, FSU height in MC group was significantly lower than that in non-MC group. Parameters concerning CL, including C2-7, FSUA, SA, were not significantly different between the two groups. The incidence of HO and high-grade HO, respectively, in the MC group was 83.7% and 30.6%, while that in the non-MC group was 53.3% and 2.2%, and such differences were significant (p < 0.05). Multivariate logistic regression analyses and Cox regression showed that MC and involved level were significantly associated with HO occurrence (p < 0.05). No implant migration and secondary surgery were observed. MC mainly affected the incidence of HO. Preoperative MC was significantly associated with HO formation after CDR and should be identified as a potential risk factor for HO. Rigorous criteria for MC should be taken into consideration when selecting appropriate candidates for CDR.

Tranexamic acid in patients with post-traumatic elbow stiffness: protocol for a randomised, double-blind, placebo-controlled trial investigating the effectiveness of tranexamic acid at reducing the recurrence of heterotopic ossification after open elbow arthrolysis

IntroductionExaggerated inflammatory response is one of the main mechanisms underlying heterotopic ossification (HO). It has been suggested that the antifibrinolytic drug tranexamic acid (TXA) can exert a significant anti-inflammatory effect...

Adjacent segment degeneration after single- and double-level cervical total disc replacement: a cohort with an over 12-year follow-up.

To characterize the change of adjacent segment degeneration (ASD) after cervical total disc replacement (CTDR) with more than 12-year follow-up, and identify the risk factors for ASD. This process included 75 patients underwent CTDR from February 2004 to December 2012, with the follow-up of 151.9 ± 36.0 (m). The artificial disc included ProDisc-C, Prestige-LP and Mobi-C. ASD was followed up at 1week, 6months, 1year, 2years, 5years, 10years after CTDR and at the endpoint of June 2022. The radiographic measurements were cervical mobility, intervertebral disc height (IDH), cervical lordosis and balance status. The complications were implant migration, subsidence and heterotopic ossification (HO). Cervical mobility in adjacent segments, IDH and lordosis showed no statistical differences between ASD and NASD group. Balance status, subsidence and migration showed no relationship with ASD. Postoperative ASD increased at 6m and especially between 6m to 2y. There was no difference between the incidence of upper ASD and lower ASD all the time and few ASD-related reoperation. The majority of adjacent segments were C4/5 (33.6%) and C6/7 (34.2%), and ASD of C5/6 had the highest incidence (61.5%). Cox regression showed ASD was not related to the types of prosthesis or operated numbers. Generalized estimating equations (GEE) analysis showed severe HO had a higher (2.68 times) probability to suffer from ASD. After over 12-year follow-up of CTDR, the occurrence of ASD and HO had temporal synchronization. ASD was not merely a natural progression but with the pathological process such as HO.

Paper 17: Follow-Up of Heterotopic Ossification (HO) After Platelet-Rich Plasma (PRP) for Groin Injuries

Objectives:A 2015 study of PRP for groin injuries in NFL players* alerted us to the possibility of PRP causing heterotopic ossification. This study of athletes seen from 2014 to 2019 provides a more comprehensive analysis of that observation.Methods:All athletes seen at one institution and identified at their first visit as having received PRP for a core muscle injury were followed and compared to core muscle injury patients who had not previously received PRP. HO was observed on MRI and intraoperatively and confirmed pathologically. All PRP patients were followed for at least two years.Results:PRP patients had a 40.7% occurrence of HO, compared to 0.7% in the non-PRP cohort (See Table). Three athletes who had PRP retired early from their sports due to the HO and scar issues. The occurrence of HO did not correlate with any technique of PRP administration. Twenty-two of 28 (78.6%) NFL players who received PRP developed HO, compared to 0 (0%) in 28 NFL randomly selected, age-, position- and injury matched controls. Three-month “success” rates were 67.9% and 96.4% respectively in the two groups (p<0.006) in terms of return to play at previously high-level levels of performance or greater, according to their own subjective assessments. Differences were mostly due to scar issues. Most “failure” patients in the PRP group had returned to play but not at their previously high levels.Conclusions:This longer-term, more comprehensive study confirms the previous preliminary analysis that caregivers should take a cautious approach to treatment with PRP for groin injuries.NoneNoneNoneTable 1.Univariable and multivariable logistic regression models predicting a final graft diameter of 8mm or more. Significant predictors are indicated in bold. 95%CI: 95% Confidence interval, BMI: body mass index.

Palovarotene Can Attenuate Heterotopic Ossification Induced by Tendon Stem Cells by Downregulating the Synergistic Effects of Smad and NF-κB Signaling Pathway following Stimulation of the Inflammatory Microenvironment.

Heterotopic ossification (HO) is defined as the formation of bone tissues outside the bones, such as in the muscles. Currently, the mechanism of HO is still unclear. Tendon stem cells (TSCs) play important roles in the occurrence and development of HO. The inflammatory microenvironment dominated by macrophages also plays an important role in the course of HO. The commonly used clinical treatment methods, such as nonsteroidal anti-inflammatory drugs and radiotherapy, have relatively large side effects, and more efficient treatment methods are needed in clinical practice. Under physiological conditions, retinoic acid receptor (RAR) signal transduction pathway inhibits osteogenic progenitor cell aggregation and chondrocyte differentiation. We focus on palovarotene, a retinoic acid γ-receptor activator, showing an inhibitory effect on HO mice, but the specific mechanism is still unclear. This study was aimed at exploring the specific molecular mechanism of palovarotene by blocking osteogenic differentiation and HO formation of TSCs in vitro and in vivo in an inflammatory microenvironment. We constructed a coculture model of TCSs and polarized macrophages, as well as overexpression and knockdown models of the Smad signaling pathway of TCSs. In addition, a rat model of HO, which was constructed by Achilles tendon resection, was also established. These models explored the role of inflammatory microenvironment and Smad signaling pathways in the osteogenic differentiation of TSCs which lead to HO, as well as the reversal role played by palovarotene in this process. Our results suggest that, under the stimulation of inflammatory microenvironment and trauma, the injured site was in an inflammatory state, and macrophages were highly concentrated in the injured site. The expression of osteogenic and inflammation-related proteins, as well as Smad proteins, was upregulated. Osteogenic differentiation was performed in TCSs. We also found that TCSs activated Smad and NF-κB signaling pathways, which initiated the formation of HO. Palovarotene inhibited the aggregation of osteogenic progenitor cells and macrophages and attenuated HO by blocking Smad and NF-κB signaling pathways. Therefore, palovarotene may be a novel HO inhibitor, while other drugs or antibodies targeting Smad and NF-κB signaling pathways may also prevent or treat HO. The expressions of Smad5, Id1, P65, and other proteins may predict HO formation.

Mid-term follow-up outcomes of single-level cervical total disc replacement versus anterior cervical discectomy and fusion for the treatment of cervical disc degenerative disease.

To evaluate the clinical and radiographic results of cervical total disc replacement (CTDR) and anterior cervical discectomy and fusion (ACDF) in the treatment of single-level cervical disc degenerative disease with a mid-term follow-up period. Seventy-two patients with C5/6 single-level cervical degenerative disc disease refractory to conservative interventions were randomly assigned to two groups: ACDF and CTDR. Clinical outcomes were assessed by using the Japanese Orthopedic Association (JOA) score and the Neck Disability Index (NDI). Radiographic evaluations included range of motion (ROM), Cobb angles, heterotopic ossification (HO) and adjacent segment degeneration during follow-up. Sixty-nine patients (35 CTDR and 34 ACDF) were followed up over 4 years (mean 50.3 months). At 1 month postoperation, the NDI scores in CTDR patients were significantly higher than those in ACDF patients, especially in the work, driving and recreation aspects. There was significant improvement in global ROM in CTDR patients than in ACDF patients. The postoperative ROM of the C4/5 segment in ACDF patients increased significantly, and no significant difference was shown in other adjacent segments. The occurrence of HO was 42.9% (15/35) in the CTDR group at the last followup, with Grade I in 3 cases, Grade II in 11 cases and Grade III in 1 case. CTDR is an effective method in the treatment of single-level cervical disc degenerative disease. Compared to ACDF, CTDR is superior in the early improvement of quality of life, and restoration of segmental motion despite radiographic evidence of HO during a mid-term follow-up period.

Research progress of traumatic heterotopic ossification

To review and evaluate the research progress of traumatic heterotopic ossification (HO). The domestic and foreign related research literature on traumatic HO was widely consulted, and its etiology, pathogenesis, pathological progress, diagnosis, prevention, and treatment were summarized. Traumatic HO is often caused by severe trauma such as joint operation, explosion injury, nerve injury, and burn. At present, it is widely believed that the occurrence of traumatic HO is closely related to inflammation and hypoxia. Oral non-steroidal anti-inflammatory drugs and surgery are the main methods to prevent and treat traumatic HO. Nowadays, the pathogenesis of traumatic HO is still unclear, the efficiency of relevant prevention and treatment measures is low, and there is a lack of specific treatment method. In the future, it is necessary to further study the pathogenesis of traumatic HO and find specific prevention and treatment targets.

THE PREVALENCE OF HETEROTOPIC OSSIFICATION AMONG PATIENTS AFTER CERVICAL DISK ARTHROPLASTY AT 5 YEARS

ABSTRACT Objective: This study was designed to evaluate the prevalence and grading of heterotopic ossification (HO) at five years, among patients after cervical disk arthroplasty (CDA). Methods: The CDA procedure with Activ C and M6-C prostheses was performed on 127 patients. The mean age of the cohort of patients was 38.4 years (range 18-49). The mean follow-up time was 58.4 months, ranging from 51 to 66 months. Results: Grade 1 ossifications were present in 11 (8.6 %) levels. A total of 45 (35.4 %) segments showed grade 2 HO. HO that led to restrictions in range of motion were present in 13 (10.2 %) cases. Five years after surgery, 9 (7.0 %) patients with grade 4 ossifications were found only in the M6-C artificial disk prosthesis group. In the analysis of patient survival following the occurrence of HO, all patients showed median survival of 28.3±5.6 months. The group that received the Activ C artificial disk prosthesis showed statistically longer survival (49.5±7.8 months) than the M6-C disk group. Conclusions: In our study 61.4% of patients exhibited HO after a mean follow-up of 58.4 months. In the analysis of patient survival after HO, all patients showed median survival of 28.3±5.6 months. The group that received the Activ C artificial disk prosthesis showed statistically longer survival (49.5±7.8 months) than the M6-C disk group. Level of evidence III; Cross-sectional Observational Study.

Clinical comparison of the over-the-top and flexor carpi ulnaris split approaches for the treatment of anteromedial facet fracture of the coronoid process.

The flexor carpi ulnaris (FCU)-split approach and the over-the-top approach have been used frequently for the fixation of anteromedial facet (AMF) fractures of the coronoid process. Clinical studies have not compared functional recovery and complication rates associated with these approaches. This study aimed to compare the clinical effectiveness of the over-the-top and FCU-split approaches for the treatment of AMF fractures of the coronoid process. Thirty-two patients who underwent surgery for AMF fractures between January 2013 and August 2019 were divided into the FCU-split and over-the-top groups. The FCU-split approach was used from January 2013 to March 2016, and the over-the-top approach was used from April 2016 to August 2019. Bony union, radiographic signs of osteoarthritis (Broberg and Morrey classification), and development of heterotopic ossification were evaluated. Postoperative pain score (visual analog scale at 2 days after the operation), surgical time (minutes), range of motion of the elbow, elbow function (Mayo Elbow Performance Score [MEPS]), and the presence of postoperative ulnar neuropathy were also compared between the 2 groups. The FCU-split and over-the-top approaches were performed in 15 and 17 patients, respectively. The mean age was 46 ± 13 years (range, 22-67 years), and the mean follow-up duration was 19± 6.7 months (range, 13-38 months). All coronoid fractures had a solid osseous union during the follow-up, and no subluxation or dislocation was observed in the 2 groups. The occurrence of heterotopic ossification and the grade of post-traumatic arthritis did not differ significantly between the groups (all P > .05). There were also no significant differences between the groups in terms of postoperative pain score, range of motion, and MEPS (all P > .05). However, the surgical time was shorter for the over-the-top approach than that for the FCU-split approach (79± 23 vs. 101 ± 14, P = .008), and the surgical time was significantly associated with the fracture classification and surgical approach (P = .001 and .003, respectively). In addition, postoperative ulnar neuropathy occurred less with the over-the-top approach than with the FCU-spilt approach (5.9% vs. 46%, P = .013). Both the FCU-split and over-the-top approaches were appropriate for performing the buttress plate fixation for AMF fractures of the coronoid process and for restoring the elbow stability. The fixation of AMF fractures through the over-the-top approach was technically easier and had less incidence of postoperative ulnar neuropathy.

Enhance the study on surgical indication for cervical artificial disc replacement and reduce the occurrence of heterotopic ossification

Heterotopic ossification(HO) and progressive bone formation(PBF) are main factors affecting the motion ability of target segments after cervical artificial disc replacement(CADR).The severity of pre-operative degeneration of target segment is the most important factor in the occurrence and progression of HO and PBF. The occurrence and progression of HO and PBF can be reduced basically through the improvement of degeneration evaluation system for intervertebral disc (including height, range of motion and osteophyte formation), uncovertebral joint and facet joint and standardization of surgical indication. The application of new anatomical prosthesis and improved surgical technique are also important factors to reduce the occurrence and development of HO and PBF.

Clinical observation on the treatment of cervical degenerative diseases with Hybrid surgery

To investigate the clinical effect of anterior cervical Hybrid surgery in the treatment of cervical degenerative diseases (CDD) and observe the incidence of heterotopic ossification of disc replacement segment at 1 year after surgery. From January 2015 to April 2018, 35 patients who received anterior cervical hybrid surgery met the inclusion and exclusion criteria and the complete clinical follow up data were analyzed retrospectively. Complete imaging follow-up data were obtained from 24 patients. There were 15 males and 20 females, aged from 39 to 70(55.57±7.73) years old. The amount of bleeding was for 20 to 100 (40.29±18.39) ml, and the hospitalstay was for 4 to 28(11.03±4.63) days, and the follow-up time was(12.97±1.36) months. Clinical outcomes were assessed by the Tanaka Yasushi cervical spondylitis symptom scale 20 score (YT20), and Japanese Orthopaedic Association (JOA) score. The occurrence of heterotopic ossification after Hybrid surgery was evaluated by X-ray according to McAfee standard one year after operation. Patients with or without heterotopic ossificationwere divided into two groups and their clinical effects were compared. At the final follow up, the mean YT20 score and JOA score were significantly higher than those before operation (P <0.05), and the average improvement rate of JOA was (70.66 ±0.44)%. One year after operation, the heterotopic ossification occurred in 10 of 24 segments, with incidence of 41.70%(10/24), including 29.20% in gradeⅠand 12.50% in gradeⅡ. The results of clinical efficacy comparison between patients with and without heterotopic ossification were as follows:there was no significant difference in JOA score before and after operation (P>0.05);there was no significant difference in YT20 score before operation (P>0.05), and YT20 score in patients with heterotopic ossification was significantly lower than that in patients without heterotopic ossification(P<0.05). The short-term clinical effect of Hybrid surgery is satisfactory for cervical degenerative diseases, and the cause of heterotopic ossification still needs tobe further explored.

Single-Cell Integration Analysis of Heterotopic Ossification and Fibrocartilage Developmental Lineage: Endoplasmic Reticulum Stress Effector Xbp1 Transcriptionally Regulates the Notch Signaling Pathway to Mediate Fibrocartilage Differentiation.

Introduction Regeneration of fibrochondrocytes is essential for the healing of the tendon-bone interface (TBI), which is similar to the formation of neurogenic heterotopic ossification (HO). Through single-cell integrative analysis, this study explored the homogeneity of HO cells and fibrochondrocytes. Methods This study integrated six datasets, namely, GSE94683, GSE144306, GSE168153, GSE138515, GSE102929, and GSE110993. The differentiation trajectory and key transcription factors (TFs) for HO occurrence were systematically analyzed by integrating single-cell RNA (scRNA) sequencing, bulk RNA sequencing, and assay of transposase accessible chromatin seq. The differential expression and enrichment pathways of TFs in heterotopically ossified tissues were identified. Results HO that mimicked pathological cells was classified into HO1 and HO2 cell subsets. Results of the pseudo-temporal sequence analysis suggested that HO2 is a differentiated precursor cell of HO1. The analysis of integrated scRNA data revealed that ectopically ossified cells have similar transcriptional characteristics to cells in the fibrocartilaginous zone of tendons. The modified SCENIC method was used to identify specific transcriptional regulators associated with ectopic ossification. Xbp1 was defined as a common key transcriptional regulator of ectopically ossified tissues and the fibrocartilaginous zone of tendons. Subsequently, the CellPhoneDB database was completed for the cellular ligand-receptor analysis. With further pathway screening, this study is the first to propose that Xbp1 may upregulate the Notch signaling pathway through Jag1 transcription. Twenty-four microRNAs were screened and were found to be potentially associated with upregulation of XBP1 expression after acute ischemic stroke. Conclusion A systematic analysis of the differentiation landscape and cellular homogeneity facilitated a molecular understanding of the phenotypic similarities between cells in the fibrocartilaginous region of tendon and HO cells. Furthermore, by identifying Xbp1 as a hub regulator and by conducting a ligand–receptor analysis, we propose a potential Xbp1/Jag1/Notch signaling pathway.

A long-term follow-up study on the occurrence of heterotopic ossification after artificial cervical disc replacement with Discover disc

Objective: To analyze the incidence of heterotopic ossification after artificial cervical disc replacement with Discover disc, and to explore the effect of heterotopic ossification on postoperative radiological and clinical efficacy. Methods: From January 2010 to January 2015, 45 patients with cervical spondylosis underwent single-level artificial cervical disc replacement in Shanghai Changzheng Hospital, including 29 cases of cervical spondylotic myelopathy, 11 cases of cervical spondylotic radiculopathy and 5 cases of mixed cervical spondylosis. At the last follow-up, Mehren grading method was used for classification of heterotopic ossification, among which, grade 0-Ⅱ was defined as low grade ossification group, and 26 patients (16 male, 10 female) were enrolled in this group; grade Ⅲ-Ⅳ was defined as high grade ossification group, and 19 patients (12 males, 7 females) were included in this group. C(2-7) Cobb angle, cervical total range of motion and range of motion at index level were used to evaluate the radiological outcomes of the two groups. Japanese Orthopaedic Association (JOA) score, neck disability index (NDI) score and visual analogue scale (VAS) were used to evaluate the clinical outcomes of the two groups. The adjacent segment intervertebral disc height and range of motion were used to evaluate the effects of heterotopic ossification on adjacent segment. Results: All patients were followed up regularly for (98±18) months. There were no statistical differences between the two groups regarding to demographic data (all P>0.05). There was no significant differences in C(2-7) Cobb angle and total range of motion between the two groups at the last follow-up (all P>0.05), but range of motion at index level in the group with low grades was significantly higher than that in the group with high grades (7.8°±6.2° vs 2.6°±1.2°, t=3.60, P<0.05). There was no significant differences in JOA score, recovery rate and NDI score between the two groups (all P>0.05). There was no significant differences in the adjacent segment intervertebral disc height before operation and at the last follow-up (both P>0.05). There was no significant differences in range of motion at adjacent segment before operation (P>0.05), while range of motion at adjacent segment in the group with low grades was significantly lower than that in the group with high grades (9.5°±1.1° vs 10.6°±1.8° and 9.4°±1.4° vs 10.5°±1.7°, repectively, t=2.54, 2.31, both P<0.05). Conclusions: Heterotopic ossification does not affect the clinical outcomes, cervical curvature and cervical total range of motion after artificial cervical disc replacement with Discover disc. However, the higher grade of heterotopic ossification, the lower range of motion at index level and the higher range of motion at adjacent segment.

How Can We Differentiate Local Recurrence From Heterotopic Ossification After Resection and Implantation of an Oncologic Knee Prosthesis in Patients with a Bone Sarcoma?

Heterotopic ossification (HO) is common after total joint arthroplasty and usually does not cause diagnostic problems. However, the occurrence of HO after oncologic prostheses implantation can be troublesome as it may mimic a locally recurrent tumor. Because this distinction could have a profound impact on the surgeon and patient, it is important to distinguish the two entities; to our knowledge, no study has evaluated this after oncologic endoprosthetic reconstruction around the knee after tumor resection. (1) How common is the occurrence of HO compared with local recurrence (LR) after resection of bone sarcoma and the use of an oncologic knee prosthesis? (2) Are there any factors associated with the development of HO after limb salvage procedures with an endoprosthesis? (3) What features allow the surgeon to differentiate HO from a locally recurrent tumor in this setting? Between 2002 and 2018, we performed 409 resections of primary bone tumors followed by reconstructions with oncologic endoprostheses. Of these, 17% (71 of 409) died before 2 years and did not have HO at that time, 2% (8 of 409) were lost to follow-up before 2 years, and another 2% (10 of 409) did not have radiographs available at a minimum of 2 years after surgery (and had not developed HO before then), and so could not be analyzed, leaving 320 patients for analysis in this retrospective study. Forty-two patients were excluded; 2% (5 of 320) for a history of failed allograft reconstruction, 3% (8 of 320) for pathologic fracture at presentation, 2% (6 of 320) for inadequate or complicated biopsy, 1% (2 of 320) for stem fractures, 2% (7 of 320) for stem loosening, and 4% (14 of 320) for extracortical bone bridging, leaving 278 patients for final evaluation. Two observers analyzed AP and lateral radiographs for signs of HO at a mean follow-up of 63 ± 33 months after surgery. We defined HO as extraskeletal bone formation in soft tissues. The primary study endpoint was survivorship free from HO, as ascertained by a competing-risks estimator. To identify factors associated with HO appearance, the demographic, radiographic, clinical, pathologic, and surgical characteristics were compared between patients with HO and those who had no lesion. Characteristic features were also compared between patients with HO and those with LR to help their differentiation. Univariate analysis was used for all statistical evaluations. HO developed in 8% (21 of 278) of patients in whom oncologic knee prosthesis was implanted. LR developed in 10% (28 of 278) of the patients. According to survivorship estimates, the HO-free survival rate was not different from the LR-free survival rate at 2 years after oncologic knee reconstruction (76 ± 5% [95% CI 63 to 87] versus 74 ± 5% [95% CI 62 to 88]; p = 0.19). History of infection was more common in patients with HO than in patients with no lesion (19% [4 of 21] versus 5% [12 of 229], Odds ratio [OR] 6 [95% CI 2 to 17]; p < 0.001). The male sex was more common in the HO group as well (76% [16 of 21] versus 55% [128 of 229], OR 2 [95% CI 1 to 5]; p = 0.03). The Modular Universal Tumor and Revision System prosthesis was more frequently used in patients with HO (67% [14 of 21]) compared to those with no lesions (40% [92 of 229]; OR 2 [95% CI 1 to 5]; p = 0.02). The lesion border in radiographs was ill-defined in 19% (4 of 21) of patients with HO and 100% (28 of 28) of patients with LR (OR 8 [95% CI 3 to 20]; p < 0.001). The median time to the appearance of HO was shorter than the time to LR (8 months [3 to 13] versus 16 months [11 to 21], [95% CI 10 to 13]; p < 0.001). Pain at presentation was more frequent in patients with LR than in those with HO (86% [24 of 28] versus 14% [3 of 21], OR 36 [95% CI 7 to 181]; p < 0.001). HO may occur after the use of oncologic knee prostheses for reconstruction after tumor resection. In most patients, HO could be differentiated from local recurrence through identifying a well-defined border on radiographs. Otherwise, factors such as an earlier time of presentation and absence of pain could suggest an HO, rather than an LR. Level III, therapeutic study.

Is There a Relationship Between Bony Fusion After Anterior Cervical Discectomy and Fusion and Heterotopic Ossification After Cervical Disc Arthroplasty in Hybrid Surgery?

Retrospective analysis. The aim of this study was to investigate the relationship between bony fusion after anterior cervical discectomy and fusion (ACDF) and heterotopic ossification (HO) after cervical disc arthroplasty (CDA) in hybrid surgery (HS). The mechanism of postoperative bone formation still remains unknown. It is considered a risk factor in CDA but is essential for a solid union in ACDF. With HS, we could directly study the mechanism and relationship of different forms of postoperative bone formation. Clinical data of 91 patients who had undergone consecutive two-level HS between January 2011 and January 2018 and with a minimum of 2-year follow-up was analyzed. HO was assessed based on McAfee's classifications, whereas fusion success was evaluated according the Food and Drug Administration approved criteria. Clinical outcomes and radiographic parameters were collected and used for the relevant comparisons. HO was identified in 48.4% of patients (44/91). The fusion rates of patients in the HO group and the non-HO group at 3, 6, and 12 months postoperatively, and the final follow-up were 81.8% and 19.1%, 95.4% and 74.5%, 95.4% and 85.1%, and 97.7% and 93.6%, respectively. The fusion rates were significantly higher at 3 and 6 months after operation in the HO group than in the non-HO group (P < 0.05). Patients in both groups had significant improvements across all clinical outcomes at final follow-up. There was a significant relationship between bony fusion and occurrence of HO after HS, suggesting that both bony fusion and HO are reflections of individual osteogenic capacity. However, a reliable predictor of postoperative bone formation is needed in the future to guarantee a solid bony fusion after ACDF and to further take full advantage of the motion-preserving from CDA. 3.

250. Occurrence and clinical implications of heterotopic ossification after cervical disc arthroplasty with Prestige LP™ disc at two contiguous levels

BACKGROUND CONTEXT Evaluation of 10-year clinical safety and effectiveness of cervical disc arthroplasty (CDA) using the Prestige LP™ disc to treat degenerative cervical spine disease at two adjacent levels has been completed. Occurrence of heterotopic ossification (HO) surrounding the prosthesis following CDA has been reported for other prostheses and found to limit the range of motion and to negatively impact function of the prosthesis. PURPOSE To assess the impact of HO on clinical outcomes and angular range of motion (ROM) after CDA with the Prestige LP™ disc at two levels. STUDY DESIGN/SETTING Multicenter, prospective, randomized, controlled, FDA-approved clinical trial. PATIENT SAMPLE A total of 209 subjects implanted with Prestige LP™ discs at two cervical levels in the clinical trial and participating in a post-approval study. The 10-year follow-up rate was 86% after excluding subjects at sites not participating in the PAS study, deaths, and withdrawals. OUTCOME MEASURES HO assessed on lateral neutral radiographs and graded 0-IV; clinical outcomes of overall success, neurological success, neck disability index (NDI), neck pain, arm pain and SF-36 Physical Component Summary (PCS) score; ROM; implant-related adverse event (AE) rate. METHODS Data were obtained as part of an FDA-approved clinical trial and a separate subgroup analysis was performed for this study. ROM was compared by HO grade, and clinical outcomes were compared between HO subgroups (Grade 0-II vs III/IV) based on HO severity at 2 and 10 years after surgery. RESULTS The Grade III/IV HO incidence at either or both index levels was 24.2% (48/198) at 2 years and 39.0% (57/146) at 10 years. No statistical difference was found in overall success, neurological success, NDI, neck pain, arm pain, or SF-36 PCS scores between the HO subgroups (Grade 0-II vs III/IV) at either 2 or 10 years. The cumulative rate of possible implant-related AEs was higher in subjects having Grade III/IV HO than those having Grade 0-II HO at 2 years (56.3% vs 24.4%) and 10 years (47.8% vs 17.9%), specifically in two subcategories: spinal events and heterotopic ossifications reported by the investigators. However, no statistical difference was found between HO subgroups in possible implant-related serious AEs or secondary surgeries at index or adjacent levels. The average angular ROMs at index levels were lower in subjects with higher-grade HO at 2 and 10 years. The average ROMs at the superior level were 8.8°, 6.6°, 3.2°, and 0.3°, respectively for HO Grade 0-I, II, III and IV groups at 10 years, and 7.9°, 6.2°, 3.7°, and 0.6°, respectively, at the inferior level. CONCLUSIONS Radiographically severe (Grade III or IV) HO after CDA with the Prestige LP disc at two levels did not significantly affect efficacy or safety (severe AEs or secondary surgeries) outcomes. However, severe HO, particularly Grade IV HO, significantly limited ROM, as expected. FDA DEVICE/DRUG STATUS Prestige LP™ Disc, Approved for 2-level cervical disc arthroplasty in 2016 (Approved for this indication)

Thrombin Hemostatic Matrix Reduces Heterotopic Ossification in Acetabular Fractures Fixed Through the Kocher-Langenbeck Approach.

To determine whether an injectable thrombin product [thrombin hemostatic matrix (THM)] at closure of a Kocher-Langenbeck approach reduces the risk of heterotopic ossification (HO) formation after an acetabular fracture. Case control. Two Level 1 trauma centers. Patients with operatively treated acetabulum fractures fixed through Kocher-Langenbeck from 2013 to 2018. Records were reviewed for demographics, history of traumatic brain injury, HO medication or radiation prophylaxis, THM (Surgiflo, Ethicon, Bridgewater New Jersey) administration, and length of follow-up. Radiographs were reviewed for dislocation, fracture, Letournel and Orthopaedic Trauma Association classifications, HO, and Brooker grade if applicable. Patients receiving HO prophylaxis (eg, nonsteroidal anti-inflammatory drugs and radiation) were excluded. Remaining patients were divided into 2 groups: THM administration (intervention) and no THM. Continuous variables were compared using t-tests and categorical variables with chi-square or Fisher's exact tests. Risk ratios for the association between HO occurrence and THM administration. Three-hundred and twenty-eight acetabular fractures met inclusion criteria (126 intervention, 202 control) in patients with a mean age of 38.7 ± 15.9 years; 62.2% were male, and 42.1% were African American. Traumatic brain injury and posterior dislocation rates were equivalent between groups (P = 0.505, 0.754, respectively). HO rate in the control group was 42.6% compared with 21.4% in the THM group (P < 0.001). Booker grade 3/4 in control group was 17.3% versus 3.2% in the THM group (P < 0.001). Patients receiving THM had a 50% reduced risk of HO (95% confidence interval 0.35-0.73) compared to those who did not; adjustment for age, gender, ethnicity, and traumatic brain injury did not meaningfully change the association (risk ratio 0.46; 95% confidence interval 0.29-0.73; P < 0.001). The use of a surgiflo product at closure of a KO approach may reduce the risk of HO formation by 50% after an acetabular fracture. Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Serum uric acid level is associated with the incidence of heterotopic ossification following elbow trauma surgery

Heterotopic ossification (HO) is a common complication after surgery for elbow trauma. Uric acid is the end product of purine metabolism and has several physiological and pathogenic roles. However, the relationship between HO and uric acid has not been explored. This retrospective study aimed to assess the relationship between HO and serum uric acid (SUA). We retrospectively reviewed data from 155 patients undergoing elbow trauma surgery in our hospital between January 2013 and December 2018. One hundred patients were included according to the inclusion criteria. They were divided into 2 groups according to the presence or absence of HO, and the SUA level was compared between groups using the independent samples t test. The optimal prognostic cutoff value was obtained using the maximum value of the Youden index. The SUA level was significantly higher in the HO group than in the non-HO group (362.0 ± 87.4 μmol/L vs. 318.3 ± 87.0 μmol/L; P < .05). Using the maximum value of Youden index, 317.5 μmol/L was determined to be the optimal SUA cutoff value for the prediction of HO, with a sensitivity of 68.75% (95% confidence interval [CI], 54.67%-80.05%) and specificity of 55.77% (95%CI,42.34%-68.40%). Our study was the first to find that the high SUA level is a risk factor for HO of the elbow joint after trauma. Moreover, 317.5 μmol/L is the SUA threshold predicting the occurrence and development of HO of the elbow, with high sensitivity and specificity.

Reinserção da ruptura distal do bíceps braquial mediante incisão única com uso de âncoras

Objective To evaluate 15 patients with ruptured distal biceps tendon submitted to reinsertion via a single, anterior and transverse approach using two anchors. They were submitted to a rehabilitation protocol and, within six months, to an evaluation of the range of motion and strength intensity during flexion and supination of the operated elbow. Methods The data were collected prospectively, and were analyzed through the Mann-Whitney test and the mixed-model test to evaluate the force between the operated and non-operated elbows. Results A total of 80% of the patients were men, 60% were injured on the dominant side, 46% were manual workers, and 73% led sedentary lifestyles. The use of anabolic steroids was reported by two patients. After the treatment, the patients recovered supination strength by 98% and flexion by 94%. According to the Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire, 73% of the patients presented the score expected of a normal population. Conclusion The single, anterior and transverse approach associated with tendon repair using anchors was esthetically satisfactory, with good strength recovery during flexion and supination, and no occurrence of heterotopic ossification.

The Effect of Footprint Mismatch on Heterotopic Ossification After Cervical Disk Replacement.

This was a retrospective study. The objective of this study was to analyze risk factors of heterotopic ossification (HO) after cervical disk replacement (CDR) and evaluate the effect of footprint mismatch on HO. Incidence of HO after CDR is high, but the exact related factors have not been fully elucidated. Radiographic data of patients who had undergone CDR with Prestige LP or Discover prosthesis in Tongji Hospital from July 2012 to December 2015 were reviewed. HO was graded according to McAfee classification and classified according to Jin morphologic classification. Footprint matching degree was evaluated using 3-dimensional computed tomographic images. Cervical sagittal alignment, functional spinal unit height, and range of motion were measured on radiographs. Preexisting degeneration was scored using Walraevens scoring system. Postulated risk factors including general factors, cervical sagittal alignment, functional spinal unit height, range of motion, postoperative biomechanical changes, preexisting degeneration, number of surgical levels, prosthesis type, use of nonsteroid anti-inflammatory drugs, and footprint matching degree were analyzed by first univariate tests, and then multivariate logistic regression was done to examine the relation with HO occurrence. Effect of footprint mismatch on type 1 HO of morphologic classification was evaluated. Data of 46 patients were collected; 43 were finally evaluated with a total 57 prostheses implanted, with a mean follow-up duration of 41.16±12.49 months. No significant differences in basic characteristics existed between 2 prosthesis groups, except follow-up time. Incidence of HO was 66.7%. Mean footprint matching degree in sagittal plane was 0.877±0.068 and in coronal plane was 0.852±0.092. Mean overall footprint matching degree was 0.699±0.102 (range: 0.388-0.993). Prosthesis type and footprint matching degree were significantly related with HO among all postulated risk factors in both univariate and multivariate analyses (P<0.05); the latter had larger Exp(B). Type 1 HO occurrence significantly related with footprint mismatch. Incidence of HO after CDR was high, and serious footprint mismatch existed. HO occurrence was significantly related with prosthesis type and footprint matching degree; the latter played a more important role.