Sternoclavicular Joint Injuries in the Contact Athlete

Traumatic Sternoclavicular Dislocations in Athletes: Diagnosis, Indications for Surgical Reconstruction, and Guide for Return to Play

Injuries to the sternoclavicular (SC) joint are rare, however, when they occur prompt recognition, evaluation, and treatment are crucial. SC joint injuries can occur following high-energy mechanisms such as motor vehicle collisions and contact sports. Injury to the SC joint can be evaluated with the use of plain radiographs as well as computed tomography. If an injury to the SC joint is suspected, injury to vital mediastinal structures must be evaluated. SC joint dislocations can be treated by either closed reduction or open reduction and stabilization. Many stabilization methods have been described including plate stabilization and ligament reconstruction.

Image registration analysis of the motion characteristics of sternoclavicular joints in sagittal motion of the upper limbs

OBJECTIVE

This study aims to accurately measure the range of motion of the sternoclavicular (SC) joint using 3D reconstruction and image registration. The motion of the SC joint is analyzed by means of axial angle representation to identify the kinematical characteristics of this joint.

METHODS

A total of 13 healthy volunteers were enrolled in the study. The limit postures of four SC joint movements were scanned by computerized tomography. The images were integrated with reconstruction and registration techniques. The range of motion of the SC joint was measured using 3D modelling. The axial angle was used to indicate the range of motion of the SC joint. The difference between the dominant side and non-dominant side was compared and the differences in axial angle of the SC joint in different postures were compared.

RESULTS

The active axial angle of the SC joint on the dominant side was approximately 1∘ higher than that of the non-dominant side when the upper limb moved from a rest position to a posteroinferior position. In the sagittal motion of the upper limbs, the axial angle of the SC joint was greatest when moving from a horizontal position to a posterosuperior position, with an average of 23.55∘. Of the flexion and extension movements of the upper limbs from a rest position to a horizontal position, 13.66% (the smallest proportion) were completed by the SC joint.

CONCLUSION

The combination of 3D reconstruction and image registration is a direct and accurate method of measuring the motion of the SC joint. Axial angle representation is an intuitive method of expressing rotation in a 3D space that allows for more convenient comparison; it is also more in line with the characteristics of human anatomy and kinesiology and therefore more accurately reflects the characteristics of joint motion. It is therefore useful for guiding clinical practice. In a physical examination, the extension of the upper limb from the horizontal position to the posterosuperior position and from the rest position to the posteroinferior position can best reflect the rotation function of the SC joint in the combined motion of shoulder joints.

Non-modifiable Risk Factors Associated with Sternoclavicular Joint Dislocations in the U.S. Military

INTRODUCTION

Sternoclavicular joint (SCJ) dislocations, although uncommon, are observed in patients with ligamentous laxity as well as those who experience traumatic injuries. The incidence and epidemiology of this costly and debilitating injury to our relatively young and active military population have not previously been reported. The purpose of this study is to consider and quantify the non-modifiable risk factors associated with this injury.

METHODS

Using Defense Medical Epidemiological Database, first-time occurrences, from 2006 to 2015 for the ICD-9-CM code 839.61 (closed dislocation of the SCJ), were obtained and further categorized by gender, race, age, rank, and branch of service. Race was classified based on self-reporting of patients into White, Black, or other categories. Age was divided into the categories of less than 20 yr, 20–24 yr, 25–29 yr, 30–34 yr, 35–39 yr, and greater than 40 yr. Rank was categorized as junior enlisted (E-1 to E-4), senior enlisted (E-5 to E-9), junior officer (O-1 to O-3), and senior officer (O-4 to O-10). Branch of service includes Army, Navy, Air Force, and Marines. Multivariate data analysis was performed to obtain rate per 1,000 person-years as well as adjusted rate (adjusted for age group, gender, race, rank, and service) to isolate risk factors.

RESULTS

Between 2006 and 2015, 427 cases of closed SCJ dislocations occurred among an at-risk population of 13,772,342 person-years for an unadjusted incidence rate (IR) of 0.031 per 1,000 person-years. The annual unadjusted IR ranged from 0.017 in 2006 to 0.059 in 2014 with the greatest increase occurring between 2006 and 2007 representing 61% increase in the rate of injuries. Males were almost twice as likely to sustain these injuries compared with females (adjusted rate ratio 1.73; 95% confidence interval [CI] 1.23, 2.43). Age was not found to be a risk factor for the development of these injuries with IRs for each age group overlapping with 95% CI for all other age groups. Similarly, the other category for race was also not found to be a statistically significant risk factor. Junior Officers (adjusted rate 0.017; 95% CI 0.011, 0.025) were found least likely to suffer from these injuries with Junior Enlisted (0.034; 95% CI 0.030, 0.040) and Senior Enlisted (0.032; 95% CI 0.028, 0.037) most at risk. Being in the Navy (0.019; 95% CI 0.015, 0.025) was found to be most protective compared with Air Force (0.032; 95% CI 0.026, 0.039), Army (0.036; 95% CI 0.031, 0.041), and Marines (0.036; 95% CI 0.028, 0.045).

DISCUSSION and CONCLUSION

Annual unadjusted IR of SCJ dislocations readily increased from 2006 to 2014. Statistically significant risk factors, for suffering a closed SCJ dislocation, identified by our study, were male sex, enlisted rank, and branch of service other than Navy. Age and race were not found to have a statistically significant risk. These results can shed light on non-modifiable risk factors for dislocations of the SCJ and can be used in other studies to aid in reducing injury burden on the U.S. Military.