The clinical implications of heterotopic ossification in patients treated with radial head replacement for trauma: A case series and review of the literature

Heterotopic ossification following severe radial head fractures: Clinical outcome and associated factors

OBJECTIVES

This study aimed to evaluate clinical outcome, prevalence, severity, location, range of motion, and possible risk factors of heterotopic ossification (HO) following severe radial head fractures.

PATIENTS AND METHODS

In this retrospective study, 73 patients (40 males, 33 females; mean age: 51.4±15 years; range, 20 to 82 years) with Mason-Johnston type 3 and 4 radial head fractures were surgically treated with osteosynthesis or radial head arthroplasty (RHA) between September 2014 and February 2021. Fifty-one were examined in person, while 22 participated via questionnaire. The clinical outcome was assessed by the range of motion, the Disabilities of the Arm, Shoulder, and Hand questionnaire (DASH), and the 36-item Short-Form Health Survey (SF-36). Operative and postoperative details and the intake of HO prophylaxis were reviewed. Heterotopic ossification severity and location was evaluated on radiographs.

RESULTS

Heterotopic ossification was present in 52.1%, while in 31.5% of all participants, RHA was needed. Overall, 46.6% received additional ligamental refixation. The mean time to surgery was 8.9±11.9 days, and the mean DASH was 13.7±16.6. In patients treated with osteosynthesis, more HO was observed for Mason-Johnston type 4 injuries compared to Mason-Johnston type 3 injuries (p=0.028). Overall, more HO was present in Mason-Johnston type 4 injuries (63.6%) compared to Mason-Johnston type 3 injuries (42.5%), without reaching significance (p=0.072). No significant association between HO and time to surgery (p=0.716), implantation of RHA (p=0.127), or ligamental refixation (p=0.121) was detected. Regardless of intake of HO prophylaxis, nearly the same amount of HO (51.7% vs. 53.8%) was present. No differences between the HO and non-HO group were detected in the DASH (p=0.553) and the SF-36 (physical component, p=0.728; mental component, p=0.275).

CONCLUSION

Over 50% surgically treated radial head fractures classified as Mason-Johnston types 3 and 4 developed HO, while more severe injuries led to a higher prevalence of HO. No increased rates of HO were determined for delayed surgery, surgical treatment methods, and use of HO prophylaxis. Therefore, regular HO prophylaxis might not be needed. Additionally, no significant differences in functional scores and quality of life were detected between patients with and without HO.

Fibroblasts in heterotopic ossification: mechanisms and therapeutic targets

Heterotopic ossification (HO) refers to the abnormal formation of bone in non-skeletal tissues. Fibroblasts have traditionally been viewed as stationary cells primarily responsible for producing extracellular matrix during tissue repair and fibrosis. However, recent discoveries regarding their plasticity-encompassing roles in inflammation, extracellular matrix remodeling, and osteogenesis-highlight their potential as key contributors to the development of HO. In this review, we systematically summarize the diverse phenotypic and functional plasticity of fibroblasts in HO. Furthermore, we evaluate the possible interaction between fibroblasts and macrophages in pathophysiological processes and signaling pathways. Finally, we highlight the potential strategies for preventing and treating HO by targeting fibroblast activities.

The outcomes of surgical treatment of complex radial head fractures

Aims

The aim of this study was to evaluate the outcome of complex radial head fractures at mid-term follow-up, and determine whether open reduction and internal fixation (ORIF) or radial head arthroplasty (RHA) should be recommended for surgical treatment.

Methods

Patients who underwent surgery for complex radial head fractures (Mason type III, ≥ three fragments) were divided into two groups (ORIF and RHA) and propensity score matching was used to individually match patients based on patient characteristics. Ultimately, 84 patients were included in this study. After a mean follow-up of 4.1 years (2.0 to 9.5), patients were invited for clinical and radiological assessment. The Mayo Elbow Performance Score (MEPS), Oxford Elbow Score (OES), and Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire score were evaluated.

Results

Patients treated with ORIF showed significantly better postoperative range of motion for flexion and extension (121.1° (SD 16.4°) vs 108.1° (SD 25.8°); p = 0.018). Postoperative functional scores also showed significantly better results in the ORIF group (MEPS 90.1 (SD 13.6) vs 78 (SD 20.5); p = 0.004). There was no significant difference between the groups in terms of the complication rate (RHA 23.8% (n = 10) vs ORIF 26.2% (n = 11)). Implant-related complications occurred in six cases (14.3%) in the RHA group and in five cases (11.9%) in the ORIF group.

Conclusion

Irrespective of the patient's age, sex, type of injury, or number of fracture fragments, ORIF of the radial head should be attempted initially, if a stable reconstruction can be achieved, as it seems to provide a superior postoperative outcome for the patient compared to primary RHA. If reconstruction is not feasible, RHA is still a viable alternative. In the surgical treatment of complex radial head fractures, reconstruction shows superior postoperative outcomes compared to RHA. Good postoperative results can be achieved even after failed reconstruction and conversion to secondary RHA. Therefore, we encourage surgeons to favour reconstruction of complex radial head fractures, regardless of injury type or number of fragments, as long as a stable fixation can be achieved.

Radial head replacement with the 3D-printed patient-specific titanium prosthesis: Preliminary results of a multi-centric prospective study

PURPOSE

To report preliminary clinical results and safety of 3D-printed patient-specific titanium radial head (RH) prosthesis in treatment of the irreparable RH fractures.

MATERIAL AND METHODS

This multi-centric prospective study included 10 patients (6 men and four women, mean age 41 years (range, 25-64 years)). Three cases were classified as Mason type III and 7 cases as type IV. Patients were assessed preoperatively, intraoperatively, and at 1, 6, 12, 24, 36, and 48 weeks postoperatively. Range of motion (ROM), visual analog scale (VAS) score, Disabilities of the Arm, Shoulder and Hand (DASH) score, Mayo Elbow Performance Score (MEPS), radiology imaging, and laboratory blood and urine testing were evaluated.

RESULTS

The prostheses were implanted utilizing cemented stems in 5 patients and cementless stems in 5 patients. Intraoperatively, well congruency of a prosthesis with capitellum and radial notch of ulna was observed in all cases. All patients had improvement of ROM, VAS score, DASH score, and MEPS during the postoperative follow-ups. At the final follow-up, mean elbow extension was 6.5° (range, 0°-30°), flexion 145° (range, 125°-150°), supination 79° (range, 70°-80°), and pronation 73.5° (range, 45°-80°). Mean VAS score was 0.3 (range, 0-3), DASH score was 12.35 (range, 1.7-23.3), and MEPS was 99.5 (range, 95-100). Postoperative radiographs demonstrated heterotopic ossification in 2 cases, periprosthetic radiolucency in 2 cases, and proximal radial neck resorption in 2 cases. No one had the evidence of capitellar erosion, implant failure, malpositioning, overstuffing, or symptomatic stem loosening. There was no significant alteration of laboratory results or adverse events related to the 3D-printed prosthesis implantation.

CONCLUSION

The preliminary results demonstrated that implantation of the 3D-printed patient-specific titanium RH prosthesis is safe and may be a potential treatment option for irreparable RH fracture.

Coronoid tip fractures in terrible triad injuries can be safely treated without fixation

INTRODUCTION

The optimal treatment of terrible triad injuries of the elbow (TTI) remains topic of ongoing discussion. The aim of this study was to determine whether different treatment strategies for coronoid tip fractures in terrible triad injuries influences the clinical and radiological results in a mid-term follow-up.

METHODS

A total of 62 patients with surgical treatment of a TTI including a coronoid tip fracture (37 women, 25 men; mean age, 51 years) were available for follow-up assessment after an average of 4.2 years (range 24-110 months). Thirteen patients had O'Driscoll 1.1 and 49 O'Driscoll 1.2 coronoid fractures, of which 26 were treated with and 36 without fixation. Range of motion, the Mayo Elbow Performance Score (MEPS), Oxford Elbow Score (OES), and Disabilities of the Arm, Shoulder and Hand (DASH) score as well as grip strength were evaluated. Radiographs were analyzed for all participants.

RESULTS

No significant benefit in outcome variables could be detected between patients, whose coronoid had been fixed, compared to patients without fixation of the coronoid. In the coronoid fixation group, patients had mean outcome scores of 81.5 ± SD 19.1 (range 35-100) for MEPS, 31.0 ± SD 12.5 (range 11-48) for OES and 27.7 ± SD 23 (range 0-61) for DASH score, while in the no-fixation group, mean MEPS was 90.8 ± SD 16.5 (range 40-100), mean OES was 39.0 ± SD 10.4 (range 16-48) and mean DASH score was 14.5 ± SD 19.9 (range 0-48). Mean range of motion was 116° ± SD 21° (range 85-140°) versus 124° ± SD 24° (range 80-150°) in extension-flexion and 158° ± SD 23° (range 70-180°) versus 165° ± SD 12° (range 85-180°) in pronation-supination. Overall complication rate was 43.5% and revision rate was 24.2%, with no significant differences between both groups. Suboptimal results were more frequently seen in patients who had degenerative or heterotopic changes on their latest radiograph.

CONCLUSIONS

Sufficient elbow stability and good outcomes can be achieved in most patients with TTI and coronoid tip fractures. Although some bias in treatment allocation and group heterogeneity cannot be completely omitted, our analysis detected no significant benefit in outcome when the coronoid tip fracture has been fixed compared to patients with non-fixed coronoid tip. Therefore, we would suggest a no-fixation approach for coronoid tip fractures as primary treatment in TTI of the elbow.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Early to midterm radiographic loosening of the press fit radial head prosthesis

BACKGROUND

Radiographic loosening is frequently seen around the radial head (RH) implant. The hypothesis of this study was that radiographic loosening will be more frequent in patients in which the RH prosthesis was implanted due to elbow trauma leading to instability that required lateral collateral ligament repair (LCL).

MATERIALS AND METHODS

A retrospective review of the patients who had RH implantation between 2012 and 2019 was performed. Evaluation included evidence of radiographic loosening, stress shielding, formation of heterotopic ossification, and rate of removal of the implant. Range of motion of the elbow at the latest follow up was also recorded.

RESULTS

At a mean follow up of 18 months (range 1.4 - 80) eight out of 25 patients had radiographic loosening around the implant. The radial head implant was removed in 8 patients (in 3 due to painful radiographic loosening, in 4 due pain without radiographic loosening and in 1 due to infection). Radiographic loosening around the RH implant had no association with LCL repair (p=0.18) or future removal of implant (p=0.18) or the diagnosis of Monteggia lesion (p=0.68). In addition, removal of the RH implant had no association with prior LCL repair (p=0.60) or the diagnosis of Monteggia lesion (p=0.15). Stress shielding was seen in 5 patients and was of no clinical significance. Heterotopic ossification was seen in 12 patients and was classified as Class I in 3, IIA in 3, IIC in 6, according to the Hastings Classification. The average flexion-extension arc was 23° to 130°, and average pronation-supination was 76° to 69°.

CONCLUSION

One third of the patients had radiographic loosening around the RH implant at a mean follow up of 18 months. Pain with or without radiographic loosening were the main reasons for removal of the implant. No associations were found between the development of radiographic loosening and LCL repair at the time of RH replacement. Limitations of this study are: (a) the retrospective design (b). the small sample size and the possibility of a type II statistical error.

Surgical treatment of the radial head is crucial for the outcome in terrible triad injuries of the elbow

AIMS

To evaluate the outcomes of terrible triad injuries (TTIs) in mid-term follow-up and determine whether surgical treatment of the radial head influences clinical and radiological outcomes.

METHODS

Follow-up assessment of 88 patients with TTI (48 women, 40 men; mean age 57 years (18 to 82)) was performed after a mean of 4.5 years (2.0 to 9.4). The Mayo Elbow Performance Score (MEPS), Oxford Elbow Score (OES), and Disabilities of the Arm, Shoulder and Hand (DASH) score were evaluated. Radiographs of all patients were analyzed. Fracture types included 13 Mason type I, 16 type II, and 59 type III. Surgical treatment consisted of open reduction and internal fixation (ORIF) in all type II and reconstructable type III fractures, while radial head arthroplasty (RHA) was performed if reconstruction was not possible.

RESULTS

At follow-up the mean MEPS was 87.1 (20 to 100); mean OES, 36.9 (6 to 48); and mean DASH score, 18.6 (0 to 90). Mean movement was 118° (30° to 150°) for extension to flexion and 162° (90° to 180°) for pronation to supination. The overall reoperation rate was 24%, with nine ORIF, ten RHA, and two patients without treatment to the radial head needing surgical revision. When treated with RHA, Mason type III fractures exhibited significantly inferior outcomes. Suboptimal results were also identified in patients with degenerative or heterotopic changes on their latest radiograph. In contrast, more favourable outcomes were detected in patients with successful radial head reconstruction after Mason type III fractures.

CONCLUSION

Using a standardized protocol, sufficient elbow stability and good outcomes can be achieved in most TTIs. Although some bias in treatment allocation, with more severe injuries assigned to RHA, cannot be completely omitted, treatment of radial head fractures may have an independent effect on outcome, as patients subjected to RHA showed significantly inferior results compared to those subjected to reconstruction, in terms of elbow function, incidence of arthrosis, and postoperative complications. As RHA showed no apparent advantage in Mason type III injuries between the two treatment groups, we recommend reconstruction, providing stable fixation can be achieved. Cite this article: Bone Joint J 2020;102-B(12):1620-1628.

Surgical treatment of the radial head is critical to the outcome of Monteggia-like lesions

Aims

The aim of this study was to evaluate the outcome of Monteggia-like lesions at midterm follow-up and to determine whether the surgical treatment of the radial head influences the clinical and radiological results.

Patients and Methods

A total of 78 patients with a Monteggia-like lesion, including 44 women and 34 men with a mean age of 54.7 years (19 to 80), were available for assessment after a mean 4.6 years (2 to 9.2). The outcome was assessed using the Mayo Elbow Performance Score (MEPS), Oxford Elbow Score (OES), Mayo Modified Wrist Score (MMWS), and The Disabilities of the Arm, Shoulder and Hand (DASH) score. Radiographs were analyzed for all patients. A total of 12 Mason type I, 16 type II, and 36 type III fractures were included. Surgical treatment consisted of screw fixation for all type II and reconstructable type III fractures, while radial head arthroplasty (RHA) or excision was performed if reconstruction was not possible.

Results

The mean MEPS was 88.9 (40 to 100), mean OES was 40.1 (25 to 48), mean MMWS was 88.1 (50 to 100), mean DASH score was 14.7 (0 to 60.2), and mean movement was 114° (sd 27) in extension/flexion and 155° (sd 37) in pronation/supination. Mason III fractures, particularly those with an associated coronoid fracture treated with RHA, had a significantly poorer outcome. Suboptimal results were also identified in patients who had degenerative changes or heterotopic ossification on their latest radiograph. In contrast, all patients with successful radial head reconstruction or excision had a good outcome.

Conclusion

Good outcomes can be achieved in Monteggia-like lesions with Mason II and III fractures, when reconstruction is possible. Otherwise, RHA is a reliable option with satisfactory outcomes, especially in patients with ligamenteous instability. Whether the radial head should be excised remains debatable, although good results were achieved in patients with ligamentous stability and in those with complications after RHA. Cite this article: Bone Joint J 2019;101-B:1512–1519

Interobserver reliability of radiographic assessment after radial head arthroplasty

BACKGROUND

Radiographs are part of routine clinical care after radial head arthroplasty (RHA). Therefore, the aim of this diagnostic study was to assess the interobserver reliability of radiographic assessment following RHA.

METHODS

Anteroposterior (AP) and lateral radiographs of 24 consecutive patients who underwent press-fit bipolar RHA were evaluated with respect to 14 parameters by 14 orthopaedic surgeons specializing in the elbow: shaft loosening (AP, lateral), subcollar bone resorption, nonbridging heterotopic ossification, capitellar erosion, capitellar osteopenia, implant size, ulnohumeral joint gapping, ulnohumeral joint degeneration, proximal radio-ulnar joint congruency, stem size, stem positioning (AP, lateral) and component dissociation or polyethylene wear of the head with increased angulation. Observer agreement was evaluated using the multirater kappa (κ) measure.

RESULTS

Nine of 14 parameters had poor interobserver agreement [κ = 0.0 to 0.20, confidence interval (CI) = 0.0 to 0.31). Four parameters had fair agreement: subcollar bone resorption (κ = 0.27, CI = 0.12 to 0.40), capitellar erosion (κ = 0.30, CI = 0.20 to 0.40), ulnohumeral joint degeneration (κ = 0.35, CI = 0.22 to 0.51) and stem positioning in AP view (κ = 0.24, CI = 0.14 to 0.36). One parameter had moderate agreement: nonbridging heterotopic ossification (κ = 0.47, CI = 0.31 to 0.64).

CONCLUSIONS

The overall interobserver reliability of radiographic assessment following press-fit bipolar RHA was poor among experienced elbow surgeons. Therefore, radiographic evaluation after RHA should be interpreted with caution when making treatment decisions.

Mid-term outcomes of 77 modular radial head prostheses

AIMS

Radial head arthroplasty (RHA) may be used in the treatment of non-reconstructable radial head fractures. The aim of this study was to evaluate the mid-term clinical and radiographic results of RHA.

PATIENTS AND METHODS

Between 2002 and 2014, 77 RHAs were implanted in 54 men and 23 women with either acute injuries (54) or with traumatic sequelae (23) of a fracture of the radial head. Four designs of RHA were used, including the Guepar (Small Bone Innovations (SBi)/Stryker; 36), Evolutive (Aston Medical; 24), rHead RECON (SBi/Stryker; ten) or rHead STANDARD (SBi/Stryker; 7) prostheses. The mean follow-up was 74.0 months (standard deviation (sd) 38.6; 24 to 141). The indication for further surgery, range of movement, mean Mayo Elbow Performance (MEP) score, quick Disabilities of the Arm, Shoulder and Hand (quickDASH) score, osteolysis and positioning of the implant were also assessed according to the design, and acute or delayed use.

RESULTS

The mean MEP and quickDASH scores were 90.2 (sd 14; 45 to 100), and 14.0 points (sd 12; 1.2 to 52.5), respectively. There were no significant differences between RHA performed in acute or delayed fashion. There were 30 re-operations (19 with, and 11 without removal of the implant) during the first three post-operative years. Painful loosening was the primary indication for removal in 14 patients. Short-stemmed prostheses (16 mm to 22 mm in length) were also associated with an increased risk of painful loosening (odds ratio 3.54 (1.02 to 12.2), p = 0.045). Radiocapitellar instability was the primary indication for re-operation with retention of the implant (5). The overall survival of the RHA, free from re-operation, was 60.8% (sd 5.7%) at ten years.

CONCLUSION

Bipolar and press-fit RHA gives unsatisfactory mid-term outcomes in the treatment of acute fractures of the radial head or their sequelae. The outcome may vary according to the design of the implant. The rate of re-operation during the first three years is predictive of the long-term survival in tight-fitting RHAs. Cite this article: Bone Joint J 2017;99-B1197-1203.

The traumatic bone: trauma-induced heterotopic ossification

Heterotopic ossification (HO) is a common occurrence after multiple forms of extensive trauma. These include arthroplasties, traumatic brain and spinal cord injuries, extensive burns in the civilian setting, and combat-related extremity injuries in the battlefield. Irrespective of the form of trauma, heterotopic bone is typically endochondral in structure and is laid down via a cartilaginous matrix. Once formed, the heterotopic bone typically needs to be excised surgically, which may result in wound healing complications, in addition to a risk of recurrence. Refinements of existing diagnostic modalities, like micro- and nano-CT are being adapted toward early intervention. Trauma-induced HO is a consequence of aberrant wound healing, systemic and local immune system activation, infections, extensive vascularization, and innervation. This intricate molecular crosstalk culminates in activation of stem cells that initiate heterotopic endochondral ossification. Development of animal models recapitulating the unique traumatic injuries has greatly facilitated the mechanistic understanding of trauma-induced HO. These same models also serve as powerful tools to test the efficacy of small molecules which specifically target the molecular pathways underlying ectopic ossification. This review summarizes the recent advances in the molecular understanding, diagnostic and treatment modalities in the field of trauma-induced HO.

Local influence of high molecular polyethylene particles on heterotopic ossification

We studied the effect of molecular polyethylene particles on local heterotopic ossification. A total of 36 healthy Sprague-Dawley rats were randomly divided into the control group (n=18) and the observation group (n=18). High molecular polyethylene particles were injected to rupture Achilles tendon position in the observation group, and normal saline was injected in the control group. X-ray examinations were conducted on Achilles tendon in the 4th, 8th and 12th week after operation. The incidence rate of heterotopic ossification was evaluated, and bone trabecula morphological structure was studied under optical microscope after hematoxylin and eosin staining. Bone morphogenetic protein 2 (BMP-2), transforming growth factor-β (TGF-β), interleukin-1 (IL-1), tumor necrosis factor-α (TNF-α), runt-related transcription factor 2 (Runx2) and matrix metalloproteinase-9 (MMP-9) expression levels were also measured. Our results showed that heterotopic ossification incidence in the observation group was significantly lower than that in the control group. Achilles tendon structure in the control group increased in volume, and its texture was harder and cartilage-like. In the observation group, trabecular bone volume, thickness and quantity were more than those observed in the control group. BMP-2, TGF-β, IL-1, TNF-α, Runx2 and MMP-9 levels in the observation group were significantly lower than those in the control group. We concluded that, high molecular polyethylene particles had a significant inhibiting effect on local heterotopic ossification.