Heterotopic ossification formation after fractures about the elbow

Bony encasement of the ulnar nerve secondary to heterotopic ossification of the elbow: an evaluation of long-term outcomes

BACKGROUND

Ulnar neuropathy at the elbow caused by heterotopic ossification (HO) is a rare condition. This retrospective study aims to report on 32 consecutive cases of ulnar nerve encasement caused by elbow HO and evaluate long-term outcomes of operative management and a standardized postoperative rehabilitation regimen.

METHODS

A retrospective case series was conducted on 32 elbows (27 patients) that underwent operative management of bony ulnar nerve encasement. All procedures were performed in the inpatient setting at an Academic Level 1 Trauma Center from September 1999 to July 2021 by one of 3 fellowship-trained shoulder and elbow. Postoperatively, all patients received formal physical therapy, HO prophylaxis (30 received indomethacin, 2 received radiation), and a structured continuous passive motion machine regimen. Patient demographics, age, gender, type of injury, history of tobacco use, and medical comorbidities were obtained to include in the analysis. Long-term follow-up examinations were performed to evaluate elbow flexion-extension arc of motion, Mayo Elbow Performance Score, and visual analog scale pain scores.

RESULTS

Thirty-two elbows with complete bony ulnar nerve encasement secondary to HO were identified (14 from burns, 15 from trauma, 3 closed head injuries). Following surgery, the mean flexion-extension arc of motion improved significantly, increasing from 21° to 100° at long-term follow-up (average 8.7 years, range 2-17 years), with statistically significant improvements in preoperative vs. long-term postoperative elbow extension (P < .001), flexion (P < .001), and total arc of motion (P < .001). There was a statistically significant improvement in pre- vs. postprocedure ulnar nerve function, as demonstrated by a decrease in average McGowan grade (1.2-0.7; P = .002). Additionally, 63% of patients with preoperative ulnar neuropathy symptoms (20/32) had either complete resolution or subjective improvement after surgery. The mean time from injury to surgery was 518 days (range 65-943 days). Age, gender, time to surgery, and medical comorbidities were not associated with outcomes. The complication rate was 9% (3/32). Patients had an average flexion-extension arc of motion of 97° and average Mayo Elbow Performance Score of 80 ("good") at long-term follow-up.

CONCLUSIONS

The combination of operative management, postoperative HO prophylaxis, and a regimented rehabilitation program has proven to be a durable solution for treating and ensuring good long-term functional outcomes for patients with elbow HO and bony ulnar nerve encasement. This treatment approach leads to superior range of motion, improved or resolved ulnar neuropathy, and good to excellent long-term functional outcomes.

Vegfc-expressing cells form heterotopic bone after musculoskeletal injury

Heterotopic ossification (HO) is a challenging condition that occurs after musculoskeletal injury and is characterized by the formation of bone in non-skeletal tissues. While the effect of HO on blood vessels is well established, little is known about its impact on lymphatic vessels. Here, we use a mouse model of traumatic HO to investigate the relationship between HO and lymphatic vessels. We show that injury triggers lymphangiogenesis at the injury site, which is associated with elevated vascular endothelial growth factor C (VEGF-C) levels. Through single-cell transcriptomic analyses, we identify mesenchymal progenitor cells and tenocytes as sources of Vegfc. We demonstrate by lineage tracing that Vegfc-expressing cells undergo osteochondral differentiation and contribute to the formation of HO. Last, we show that Vegfc haploinsufficiency results in a nearly 50% reduction in lymphangiogenesis and HO formation. These findings shed light on the complex mechanisms underlying HO formation and its impact on lymphatic vessels.

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.

Rate of Complications After Capitellum Fracture Fixation: A Systematic Review and Meta-Analysis

PURPOSE

This systematic review aimed to determine the incidence of complications following surgical fixation of an acute capitellum fracture. We secondarily aimed to compare the complication rate between anterior-to-posterior (A-P) versus posterior-to-anterior (P-A) screw insertion.

METHODS

PubMed, EMBASE, and Scopus were searched to identify studies on surgical fixation of capitellum fractures in skeletally mature patients. The main outcome was the rate of complication after fracture fixation. Subgroup analysis was performed to assess the impact of the fixation technique on the outcomes after surgery. An inverse variance method using random or fixed effects models was used to perform a meta-analysis based on the degree of heterogeneity between studies. Study heterogeneity was evaluated using Q statistics to calculate the I2 index.

RESULTS

We included 42 studies in the final analysis. The most reported complications after surgical fixation of capitellum fractures included elbow pain (21%), radiocapitellar arthritis (19%), hardware removal (17%), and heterotopic ossification (13%). When groups were stratified based on the direction of screw insertion, the mean rate of avascular necrosis was higher in the P-A direction (29% vs 11%). In comparison, the rate of revision fixation (2.9% vs 6.7%) and heterotopic ossification (7.3% vs 22%) were higher in the A-P direction. Transient posterior interosseous nerve palsy was reported in four patients in four studies, of whom three patients had A-P screw fixation.

CONCLUSION

Fixation of a displaced capitellum fracture is recommended when possible. However, patients should be counseled about the potential risk of complications and chances of undergoing an unplanned surgery.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

[Elbow joint dislocation : Frequent concomitant injuries and current treatment concepts]

Dislocations of the elbow joint are among the most prevalent dislocation injuries in the human body after shoulder joint dislocations and represent a challenge in the clinical routine because of the concomitant injuries and complications. They predominantly affect young adults who become injured during athletic or daily activities. A distinction is generally made between a simple elbow dislocation and a dislocation fracture of the elbow; however, a uniform classification or treatment algorithm has not yet been established, especially for simple elbow dislocations with associated ligamentous, muscular and capsular concomitant injuries. Due to this and the complexity of this injury, a standardized approach is needed to initiate the optimal treatment at an early stage and to correctly select the narrow treatment pathway between impending chronic instability and elbow stiffness.

Posttreatment Changes of the Elbow

Radiologists should be familiar with the typical surgical procedures applied at the elbow and aware of the spectrum of normal and pathologic appearances of posttreatment situations throughout all radiologic modalities. Most important in the case of posttraumatic surgical elbow procedures is correct postoperative elbow joint alignment, appropriate fixation of joint-forming fragments, and proper insertion of screws, plates, and anchor devices that do not conflict with intra-articular or bony structures. To report soft tissue repair procedures correctly, radiologists need to know the broad spectrum of different techniques applied and their appearance on magnetic resonance imaging.

The Diagnostic Value of Scanning in the Injury of Triceps Crus of Volleyball Players

The study goal is to solve the problem of the diagnosis of triceps crus injury of volleyball players, meet the needs of volleyball players and team doctors for the correct diagnosis of triceps crus injury scanning, make up for the deficiency that triceps crus injury scanning diagnosis is easy to make mistakes, and improve the efficiency and ability of triceps crus injury diagnosis scanning. Because the experiment involves the technical action of volleyball jump serve, DELSYSR Trignomobile wireless portable surface electromyography tester (16 leads) made in the United States is selected to test the surface electromyography of the main muscle groups of college male volleyball players in the process of jump serve. The German made simi-3D motion image system is used to conduct three-dimensional synchronous test of athletes' jump serve action. The data analysis software adopts EMG work analysis, EMG analysis software, and simi-3D motion image analysis system for postprocessing data. The original signal is filtered (400 Hz for low pass and 20 Hz for high pass) and rectified. Finally, IEMG, EMG contribution rate, and RMS were calculated. This ensures the accuracy of the experiment.