Heterotopic ossification after total elbow arthroplasty: a systematic review

Heterotopic ossification of the elbow joint in a child: Successful surgical resection - A case report

Background

This case report describes the occurrence of a rare heterotopic ossification of the elbow joint in a child, caused by inappropriate movement after trauma. A successful operation to remove heterotopic ossification was described in the report with satisfactory results.

Case presentation

A 7-year-old boy suffered a supracondylar fracture of the humerus after an accidental fall, and after immobilization with a cast, improper movement resulted in heterotopic ossification of the elbow joint, which severely affected joint function. The heterotopic ossification was surgically removed and a complete recovery was demonstrated at 18 months follow-up. The heterotopic ossification was successfully removed with good elbow function and no recurrence at 18 months follow-up.

Conclusions

The purpose of this report is to show the good results with surgical treatment of heterotopic ossification of the elbow joint in children,when conservative treatment does not work.

The significance of heterotopic ossification following total ankle arthroplasty: a systematic review and meta-analysis

PURPOSE

The purpose of this systematic review and meta-analysis was to evaluate the prevalence and clinical significance of heterotopic ossification (HO) following total ankle replacement (TAR).

METHODS

During August 2023, the PubMed, Embase and Cochrane library databases were systematically reviewed to identify clinical studies reporting HO following TAR. Data regarding surgical characteristics, pathological characteristics, subjective clinical outcomes, ankle range of motion, radiographic outcomes, reoperation rates were extracted and analysed.

RESULTS

Twenty-seven studies with 2639 patients (2695 ankles) at a weighed mean follow-up time of 52.8 ± 26.9 months were included. The pooled prevalence rate was 44.6% (0.25; 0.66). The implant with the highest rate of HO was the INBONE I (100%) and BOX (100%) implants. The most common modified Brooker staging was grade 1 (132 patients, 27.0%). Random effects models of standardized mean differences found no difference in American orthopedic foot and ankle society (AOFAS) scores, visual analog scale scores (VAS) and ankle range of motion (ROM) between patients with HO and patients without HO. Random effects models of correlation coefficients found no correlation between AOFAS, VAS and ROM and the presence of HO. The surgical intervention rate for symptomatic HO was 4.2%.

CONCLUSION

This systematic review and meta-analysis found that HO is a common finding following TAR that is not associated with inferior clinical outcomes. Surgical intervention was required only for moderate-to-severe, symptomatic HO following TAR. This study is limited by the marked heterogeneity and low level and quality of evidence of the included studies. Further higher quality studies are warranted to determine the precise prevalence and impact of HO on outcomes following TAR.

LEVEL OF EVIDENCE III

Classification and Incidence of Heterotopic Ossifications in Relation to NSAID Prophylaxis after Elbow Trauma

Heterotopic ossification (HO) after elbow trauma can be responsible for significant motion restrictions. The study's primary aim was to develop a new X-ray-based classification for HO of the elbow. This retrospective study analyzed elbow injury radiographs from 138 patients aged 6-85 years (mean 45.9 ± 18) who underwent operative treatment. The new classification was applied at 6 weeks, 12 weeks, and 6 months postoperatively. The severity of HO was graded from 0 to 4 and localization was defined as r (radial), p (posterior), u (ulnar) or a (anterior) by two observers. The patients were categorized based on injury location and use of non-steroidal anti-inflammatory drugs (NSAIDs) for HO prophylaxis. The correlations between the generated data sets were analyzed using Chi-square tests (χ2) with a significance level of p < 0.05. The inter- and intraobserver reliability was assessed using Cohen's Kappa. In 50.7% of the evaluated X-rays, the formation of HO could be detected after 12 weeks, and in 60% after 6 months. The analysis showed a significant correlation between the injury's location and the HO's location after 12 weeks (p = 0.003). The use of an NSAID prophylaxis did not show a significant correlation with the severity of HO. The classification showed nearly perfect inter- (κ = 0.951, p < 0.001) and intrareliability (κ = 0.946, p < 0.001) according to the criteria of Landis and Koch. Based on the presented classification, the dimension and localization of HO in the X-ray image can be described in more detail compared to previously established classifications and, thus, can increase the comparability of results across studies.

Prevalence, Timing, Locational Distribution, and Risk Factors for Heterotopic Ossification After Elbow Arthroscopy

BACKGROUND

Arthroscopic techniques aim to reduce complications and accelerate recovery of the elbow after treatments for posttraumatic stiffness, arthritis diseases, lateral epicondylitis, ligament reconstruction, and elbow trauma. However, data on the true prevalence and characteristics of heterotopic ossification (HO) formation after elbow arthroscopy are limited.

PURPOSE

To investigate the prevalence, timing, locational distribution, and risk factors of HO after elbow arthroscopy.

STUDY DESIGN

Cohort study; Level of evidence, 4.

METHODS

Data on 205 patients undergoing elbow arthroscopy by a single senior elbow surgeon at a single institution between May 2011 and January 2022 were retrospectively reviewed. The patients were evaluated at 2 weeks, 8 weeks, 6 months, and then annually after surgery or more frequently if HO developed, with a minimum of 1 year of postoperative follow-up. Postoperative anteroposterior and lateral elbow radiographs were taken at 2 weeks to rule out fracture and at 8 weeks to identify HO. The clinical outcomes were evaluated based on the pain visual analog scale; the shortened version of the Disabilities of the Arm, Shoulder and Hand score; Mayo Elbow Performance Score; and the Single Assessment Numeric Evaluation scores before and after surgery. Bivariate logistic regression analyses were used to determine factors affecting HO prevalence.

RESULTS

Thirteen (12 male, 1 female) of 205 (6.3%) patients developed HO, with 10 (76.9%) with HO that formed on the medial compartment of the elbow. Ten (76.9%) patients were diagnosed at 8 weeks after arthroscopic surgery, 1 (7.7%) at 6 months after surgery, and 2 (15.4%) at 12 months after surgery. HO was not found at 2 weeks after surgery in any patient. The mean follow-up time was 3.5 years (range, 1.0-11.8 years). Eleven asymptomatic patients were treated nonoperatively, and 2 symptomatic patients underwent HO excision arthroscopically or had a combination of open surgery and arthroscopy. Age was a protective factor for HO formation (odds ratio [OR], 0.953; 95% CI, 0.910-0.999; P = .047). The risk factors for HO formation were tourniquet time (OR, 1.042; 95% CI, 1.019-1.065; P < .001) and surgical time (OR, 1.026; 95% CI, 1.011-1.041; P < .001).

CONCLUSION

Among 205 patients who underwent elbow arthroscopy, HO was a minor complication of elbow arthroscopy, with a prevalence rate of 6.3%, and was usually located on the medial compartment of the elbow. Although the presence of HO may not affect the clinical outcomes in most patients, it should be carefully monitored for a minimum of 8 weeks postoperatively. Younger age, longer tourniquet time, and longer surgical time contributed to HO formation after elbow arthroscopy.

Interobserver and Intraobserver Reliability of Classification Systems for Radiographic Complications After Radial Head Arthroplasty

PURPOSE

Although several classifications are used to assess radiographs following radial head arthroplasty (RHA), including the Popovic classification for radiolucency, the Chanlalit classification for stress shielding (SS), the Brooker classification for heterotopic ossification (HO), and the Broberg-Morrey classification for radiocapitellar arthritis, little is known about the reliability of these classification systems. The purpose of this study was to determine the interobserver and intraobserver reliability of these classifications.

METHODS

Six orthopedic surgeons at various levels of training reviewed elbow radiographs of 20 patients who underwent RHA and classified them according to the Popovic, Chanlalit, Brooker, and Broberg-Morrey classifications for radiolucency, SS, HO, and RHA, respectively. Four weeks after initial review, radiographic reviews were repeated. Reliability was measured using the Fleiss kappa and the intraclass correlation coefficient. Agreement was interpreted as none (<0), slight (0.01-0.2), fair (0.21-0.4), moderate (0.41-0.6), substantial (0.61-0.8), and almost perfect (0.81-1) based on agreement among attending surgeons.

RESULTS

Among fellowship-trained attending surgeons, interobserver reliability was slight for SS (Chanlalit) and the categorical interpretation of radiolucency (Popovic), fair for radiocapitellar arthritis (Broberg-Morrey) and HO (Brooker), and substantial for the ordinal interpretation of radiolucency (Popovic). Residents had a higher interobserver reliability than attending physicians when using the Brooker classification. Mean intraobserver reliability was fair for SS (Chanlalit) and the categorical interpretation of radiolucency (Popovic), moderate for HO (Brooker) and radiocapitellar arthritis (Broberg-Morrey), and almost perfect for the ordinal interpretation of radiolucency (Popovic). Trainees had higher intraobserver reliability than attending surgeons using the SS (Chanlalit) classification.

CONCLUSIONS

The number of Popovic zones is reliable for communication between physicians, but caution should be taken with the Brooker, Chanlalit, Broberg-Morrey, and categorical interpretation of the Popovic classifications. All the classifications had better intraobserver than interobserver reliability.

CLINICAL RELEVANCE

Reliability of classification systems for radiographic complications after RHA is less than substantial except the number of zones of radiolucency; therefore, caution is required when drawing conclusions based on these classifications.

Relatively Low Rate of Heterotopic Ossification Following Primary Total Knee Arthroplasty: A Systematic Review and Meta-analysis

BACKGROUND

Heterotopic ossification (HO) is abnormal growth of ectopic bone and negatively affects the outcomes after total knee arthroplasty (TKA). This systematic review and meta-analysis were performed to characterize the prevalence and severity of HO after primary TKA.

METHODS

A systematic review of the literature was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Patient demographics, publication year, and HO prevalence after a primary TKA were recorded. A meta-analysis was performed to determine the overall prevalence of HO formation, and a subanalysis compared the studies published in different timeframes to determine whether a temporal effect exists for HO prevalence.

RESULTS

Two thousand nine hundred eighty-eight patients underwent primary TKA across the included studies. Fourteen percent of patients (9% to 20%; I2: 93.68%) developed HO postoperatively during a mean follow-up of 40.1 months (11 to 108 months). HO rates seemed to decrease in studies published in more recent years, with a pooled HO prevalence of 5% (0% to 13%; I2: 92.26%) among studies published in the past 15 years compared with 18% (12% to 25%; I2: 92.49%) among studies published before then.

CONCLUSION

Although studies reported a relatively low overall rate of HO after a primary TKA, the absence of a single, standardized classification system precludes the comparisons of HO severity between studies. Overall, HO prevalence seems to have decreased over time, likely reflecting the changes in perioperative medication protocols.

Outcomes following revision of the revision total elbow arthroplasty

BACKGROUND

There is very little information in the literature on the outcomes of revision of revision total elbow arthroplasty (RRTEA). Our aim was to report the outcomes of this rarely performed procedure.

METHODS

We retrospectively identified all patients who had undergone RRTEA between 2007 and 2016. Outcomes were assessed clinically using a number of validated systems, and radiographs were reviewed for prosthesis alignment, cementation by Morrey grading, and heterotopic ossification.

RESULTS

We identified 22 patients who underwent RRTEA. Of these patients, 14 were available for assessment (2 died of unrelated causes, 2 could not be contacted, 2 declined to participate because of travel difficulties, and 2 had incomplete data). At the final review, the median age was 73 years (range, 57-83 years), with a median follow-up period of 4.5 years (range, 2-7 years) since the last surgical procedure. The median number of previous revision arthroplasty procedures per patient was 3 (range, 2-6). The indications for RRTEA were aseptic loosening (60%), bushing wear (16%), fracture (14%), and infection (10%). Of the patients, 30% required extra-long or custom-made implants and 50% needed allograft augmentation. At final clinical assessment, 56% of patients had triceps insufficiency, the median flexion-extension arc was 90°, and the median prono-supination arc was 95°. The functional elbow scores revealed good outcomes in the majority of patients (median visual analog scale score, 5; median Oxford Elbow Score, 22; median Mayo Elbow Performance Index score, 55; and median QuickDASH [short version of Disabilities of the Arm, Shoulder and Hand questionnaire] score, 63). Eighty-one percent of patients were satisfied with their RRTEAs. Complications included infection in 2 patients (1 superficial and 1 deep), symptomatic aseptic humeral component loosening in 1, sensory ulnar nerve symptoms in 2, and radial nerve injury in 1. One patient required ulnar nerve release. Radiologic review revealed asymptomatic loosening in 1 patient (humeral component), and overall prosthesis alignment with cementation was adequate in 81%. Heterotopic ossification was present in 38% of cases.

CONCLUSIONS

RRTEA is a satisfactory treatment option in these complex cases, with good short- to mid-term survival rates but a relatively high complication rate.

Heterotopic Ossification in Orthopaedic and Trauma surgery: A Histopathological Ossification Score

Heterotopic Ossification (HO) is a potential long-term complication in orthopaedic surgery. It is commonly classified according to the Brooker classification, which is based on radiological findings. To our knowledge the correlation of histological features to the Brooker grade is unknown as is the association between HO and the indication for revision. The aim of this paper is to analyze the ossification grade of HO tissue in patients undergoing revision hip and knee arthroplasty and to propose a histologically based classification system for HO. We also assess the relationship between the grade of HO and the indication for revision (septic and aseptic revision). From January to May 2019 we collected 50 human HO samples from hip and knee revision arthroplasty cases. These tissue samples were double-blinded and sent for histopathological diagnostic. Based on these results, we developed a classification system for the progression of HO. The grade of ossification was based on three characteristics: Grade of heterotopic ossification (Grade 1–3), presence of necrosis (N0 or N1) and the presence of osteomyelitis (HOES-Score Type 1 to 5). Demographic data as well as surgical details and indication for surgery was prospectively collected from clinical records. Fifty tissue samples were harvested from 44 hips and 6 knee joints. Of these 33 exhibited Grade I ossifications (66%), followed by 11 Grade II (22%) and one Grade III (2%). Necrosis was noted in two tissue samples (4%) and 2 more had osteomyelitis findings according to HOES-Score. Six samples (12%) with radiologically suggestive of HO turned out to be wear-induced synovitis, SLIM Type 1. Of these cases 16 were septic (32%) and 34 aseptic (68%) revisions. Most of the HO tissue samples were classified as a low-grade. High-grade ossification-Score is rare. Higher grades of ossification seem to be associated with septic revision cases. Wear-induced synovitis potentially influences HO development. A histological scoring system for ossification grading can be derived from the data presented in this study.

Celecoxib cannot inhibit the progression of initiated traumatic heterotopic ossification

BACKGROUND AND HYPOTHESIS

Heterotopic ossification (HO) is a recognized sequela after trauma and arthroplasty. The purpose of this study was to evaluate the therapeutic effect of celecoxib on HO. We hypothesized that celecoxib may inhibit the progression of initiated HO.

METHODS

We performed a retrospective review of 37 patients who underwent elbow joint surgery between January 2014 and June 2018. Seventeen patients were prescribed orally administered celecoxib (200 mg/dose, twice daily) for 2 months after the diagnosis of HO, whereas the remaining 20 patients were administered celecoxib for 1 month starting immediately after surgery. HO progression was evaluated by plain radiographs. By use of an Achilles tendon puncture-induced HO mouse model, the curative effect of celecoxib was illustrated at different HO progression stages. The mice were assigned to 1 of 4 groups: sham group, vehicle group, group receiving celecoxib on day 1, and group receiving celecoxib in week 6. Achilles tendons were analyzed by micro-computed tomography and histochemistry after 12 weeks.

RESULTS

Celecoxib did not inhibit the progression of initiated HO in the patients in whom HO was diagnosed, whereas those who received celecoxib after surgery had lower morbidity. Achilles tendon puncture effectively induced typical HO in mice. The ectopic bone volume was significantly reduced in the day 1 celecoxib group compared with the vehicle group; however, the difference was not statistically significant in the week 6 celecoxib group.

CONCLUSIONS

Administration of celecoxib starting immediately after surgery can significantly inhibit the formation of HO. Once HO is visible on plain radiographs or micro-computed tomography, celecoxib cannot effectively attenuate further progression of HO in humans and mice.

In vivo model of human post-traumatic heterotopic ossification demonstrates early fibroproliferative signature

Background

The relationship between the tissue injury healing response and development of heterotopic ossification (HO) is poorly understood. Here we compare a rat blast model and human traumatized muscle from a blast injury to study the early signatures of osteogenesis and fibrosis during the formation of HO.

Methods

Rat and human tissues were characterized using histology, scanning electron microscopy, immunohistochemistry, as well as gene and protein expression analysis. Additionally, animals and humans were assessed radiographically for HO formation following injury.

Results

Markers of bone formation were dramatically increased in tissue samples from both humans and rats, and both displayed increased fibroproliferative regions within the injured tissues and elevated expression of markers of tissue fibrosis such as TGF-β1, Fibronectin, SMAD3 and PAI-1. Markers of inflammation and fibrosis (ACTA, TNFα, BMP1 and BMP3) were elevated at the RNA level in both rat and human samples. By day 42, bone formation in the rat blast model appeared similar in radiographs compared to human patients who progressed to develop post-traumatic HO.

Conclusions

Our data demonstrates that a similar early fibrotic response is evident in both the rat blast model and the human tissues following a traumatic injury and demonstrates the relevance of this animal model for future translational studies.