Radiographic evaluation of the acromioclavicular and sternoclavicular joints

Physiotherapeutic Management for Acromioclavicular Joint Sprain With Volar Intercalated Segment Instability at the Wrist: A Case Report

Among sports enthusiasts and young individuals, acromioclavicular (AC) joint injuries are highly prevalent. In this, we discussed the comprehensive assessment and management of a 22-year-old male patient who is a student by occupation and a recreational badminton player who presented with left shoulder and wrist pain following a road traffic accident. The study highlights the clinical findings, diagnostic assessment, and therapeutic interventions for the patient with volar intercalated segment instability and a grade 1 AC joint sprain. The methodology involves a case report of the patient's clinical evaluation, including range of motion, manual muscle testing, and diagnostic imaging. The patient was managed conservatively with physiotherapy interventions, including Mulligan's movement with mobilization, cryotherapy, light amplification by stimulated emission of radiation, and progressive exercises. The results of the study demonstrate the successful implementation of a multidisciplinary conservative management approach for alleviating pain, restoring function, and promoting optimal recovery for the patient. The implications of the study underscore the significance of tailored physical therapy rehabilitation in the management of AC joint sprains and wrist instabilities.

Physeal injuries of the clavicle: pediatric counterparts to adult acromioclavicular and sternoclavicular joint separations

The epiphyses at the medial and lateral ends of the clavicle are small, ossify relatively late, and may not fuse until early adulthood. Because of this unique anatomy, pediatric and young adult injuries that involve the clavicle often differ from the patterns typically seen in older adults. Clavicular trauma that affects the acromioclavicular joint laterally or sternoclavicular joint medially often results in a physeal fracture and as such, can go unrecognized or be mistaken for a joint dislocation. Radiographic assessment is challenging, particularly when the epiphysis is not yet ossified. However, MR imaging allows for visualization of the cartilage, periosteum and perichondrium, and ligaments of the affected joints. Lateral clavicle physeal injuries can be categorized by the Dameron and Rockwood system, the pediatric correlate to the Rockwood classification of adult acromioclavicular joint injuries. Medial clavicle physeal fractures, similar to adult sternoclavicular joint dislocations, may result in anterior or posterior displacement. Because of their great ability to heal and remodel, clavicular physeal fractures respond better to conservative management than true acromioclavicular or sternoclavicular joint dislocations. Therefore, it is essential to recognize the true nature of these injuries, as there are implications for successful treatment and appropriate prognosis.

Salmonella Sternoclavicular Septic Arthritis in a Non-sickle Cell Disease Patient

Septic arthritis is one of the most common orthopedic emergencies. In most cases, the joints affected are large (e.g., knees, hips, and ankles). The presentation of septic arthritis in the sternoclavicular joint (SCJ) has a relatively low prevalence rate, most commonly found in intravenous drug users. Staphylococcus aureus is the most common pathogen identified. We report a case of a 57-year-old male with a known case of diabetes mellitus, hypertension, and ischemic heart disease who complained of chest pain and was later found to have right-side SCJ septic arthritis. The procedure involves aspiration of pus using ultrasound guidance as well as irrigation of the right SCJ. The result of a pus culture from the right SCJ (a rare joint to be affected) was Salmonella, which is an atypical infection, specifically in non-sickle cell disease patients. The patient was treated with a specific antibiotic covering this pathogen.

Anatomical variants of the acromioclavicular joint influence its visibility in the standard MRI protocol in patients aged 18-31 years

Purpose

Visualization of a structure in orthogonal planes is essential for correct radiological assessment. The aim was to assess the utility of the standard MRI protocol for the shoulder in the assessment of the acromioclavicular joint (ACJ).

Methods

A total of 204 MRI scans of the shoulder were re-reviewed. Visibility of the ACJ in orthogonal planes was assessed, and the type of acromion and the angle between the ACJ and the glenoid cavity were assessed by two observers.

Results

Agreement in the assessment of ACJ visibility was moderate to substantial. The ACJ was visible in the three anatomical views in 48% (confidence interval [CI] 95% = [41–54%]) of the examinations, and no significant difference regarding gender or age was noticed. The mean angle between the ACJ and the glenoid cavity was 41.12 deg. CI95% = (39.72, 42.53) in the axial plane, 33.39 deg. CI95% = (31.33, 35.45) in the coronal plane and 52.49 deg. CI95% = (50.10, 54.86) in the sagittal plane. When the ACJ was visible in the sagittal and axial planes, significant differences were noticed in the remaining planes (p < .05).

Conclusion

Anatomical variations of the ACJ influence its visibility in the standard MRI protocol for examining the shoulder, making this protocol insufficient for ACJ assessment in the examined population.

Usefulness of the acromioclavicular joint cross-sectional area as a diagnostic image parameter of acromioclavicular osteoarthritis

BACKGROUND

Acromioclavicular joint (ACJ) space narrowing has been considered to be an important diagnostic image parameter of ACJ osteoarthritis (ACJO). However, the morphology of the ACJ space is irregular because of osteophyte formation, subchondral irregularity, capsular distention, sclerosis, and erosion. Therefore, we created the ACJ cross-sectional area (ACJCSA) as a new diagnostic image parameter to assess the irregular morphologic changes of the ACJ.

AIM

To hypothesize that the ACJCSA is a new diagnostic image parameter for ACJO.

METHODS

ACJ samples were obtained from 35 patients with ACJO and 30 healthy individuals who underwent shoulder magnetic resonance (S-MR) imaging that revealed no evidence of ACJO. Oblique coronal, T2-weighted, fat-suppressed S-MR images were acquired at the ACJ level from the two groups. We measured the ACJCSA and the ACJ space width (ACJSW) at the ACJ on the S-MR images using our imaging analysis program. The ACJCSA was measured as the cross-sectional area of the ACJ. The ACJSW was measured as the narrowest point between the acromion and the clavicle.

RESULTS

The average ACJCSA was 39.88 ± 10.60 mm² in the normal group and 18.80 ± 5.13 mm² in the ACJO group. The mean ACJSW was 3.51 ± 0.58 mm in the normal group and 2.02 ± 0.48 mm in the ACJO group. ACJO individuals had significantly lower ACJCSA and ACJSW than the healthy individuals. Receiver operating characteristic curve analyses demonstrated that the most suitable ACJCSA cutoff score was 26.14 mm², with 91.4% sensitivity and 90.0% specificity.

CONCLUSION

The optimal ACJSW cutoff score was 2.37 mm, with 88.6% sensitivity and 96.7% specificity. Even though both the ACJCSA and ACJSW were significantly associated with ACJO, the ACJCSA was a more sensitive diagnostic image parameter.

Bony Edema and Clinical Examination Findings Predict the Need for Distal Clavicle Excision at the Time of Shoulder Arthroscopy

Background: Deciding to perform a distal clavicle excision for acromioclavicular joint arthritis, especially in conjunction with other arthroscopic shoulder procedures, is challenging for surgeons. Studies have reported mixed results on the value of magnetic resonance imaging (MRI) in decision making. Purpose: We sought to correlate MRI findings with clinical symptoms and the surgeon's decision to perform a distal clavicle excision. Methods: We compared MRI, clinical examination, and MRI findings of 200 patients who underwent distal clavicle excision for symptomatic acromioclavicular joint arthritis with 200 patients who underwent arthroscopic shoulder procedures for other reasons. Univariate statistics were used to determine correlations between physical examination findings, MRI findings, and the decision to perform distal clavicle excision. A binary logistic regression model was used to determine independent predictors of need for distal clavicle excision. Results: There was no difference in mean age, sex, and race between groups. Advanced acromioclavicular joint osteoarthritis was strongly correlated with positive physical examination findings. Bony edema correlated strongly with tenderness at the acromioclavicular joint but not pain with cross-body adduction testing. There was no association between higher MRI grade of osteoarthritis and the need for distal clavicle excision. Regression analysis identified both physical examination findings and bony edema on MRI as independent predictors of the need for distal clavicle excision. Conclusion: In the setting of positive clinical examination findings and bony edema of the distal clavicle, surgeons should feel reassured that distal clavicle excision is likely indicated.

Anatomic reconstruction of the coracoclavicular and acromioclavicular ligaments with semitendinosus tendon graft for the treatment of chronic acromioclavicular joint dislocation provides good clinical and radiological results

PURPOSE

To evaluate clinical and radiographic outcomes of anatomical reconstruction of the coracoclavicular and acromioclavicular ligaments with single-strand semitendinosus tendon graft for the treatment of chronic acromioclavicular joint dislocation.

METHODS

Patients affected by chronic type III-V acromioclavicular joint dislocations were included. Exclusion criteria were: age under 18 years, concomitant rotator cuff tears, previous surgery to the same shoulder, degenerative changes of the glenohumeral joint, infections, neurologic diseases, patients with a previous history of ligament reconstruction procedures that had required harvesting of the semitendinosus tendon from the ipsilateral or contralateral knee. All patients underwent the same surgical technique and rehabilitation. Primary outcome was the normalized Constant score. Secondary outcomes were: DASH score, radiographic evaluation of loss of reduction and acromioclavicular joint osteoarthritis.

RESULTS

Thirty patients with a mean age of 28.9 ± 8.3 years were included. Mean time to surgery was 12.8 ± 10 months. Mean follow-up was 28.1 ± 2.4 months (range: 24-32). Comparison between pre- and postoperative functional scores showed significant clinical improvement (p < 0.001). Time to surgery was independently associated with a poorer Constant score (p < 0.0001). On radiographs, 4 patients (13.3%) showed asymptomatic partial loss of reduction.

CONCLUSION

Anatomic reconstruction of coracoclavicular and acromioclavicular ligaments using a semitendinosus tendon graft for the treatment of chronic acromioclavicular joint dislocation provided good clinical and radiological results at minimum 2-year follow-up.

LEVEL OF EVIDENCE

Level III.

No differences between conservative and surgical management of acromioclavicular joint osteoarthritis: a scoping review

PURPOSE

To conduct a scoping review to clarify the management of acromioclavicular joint osteoarthritis, as well as to identify any existing gaps in the current knowledge.

METHODS

Studies were identified by electronic databases (Ovid, Pubmed) from their inception up to April 2nd, 2020. All studies reporting functional outcomes after conservative or surgical treatment of acromioclavicular joint osteoarthritis, either primary or secondary to trauma or distal clavicle osteolysis, were included. Following data were extracted: authors, year of publication, study design (prospective or retrospective), LOE, number of shoulders treated conservatively or surgically, patients' age, OA classification, type of conservative treatment, surgical approach, surgical technique, functional outcomes, complications, revisions, and length of follow-up. Descriptive statistics was used. Quality appraisal was assessed through the Cochrane risk of bias tool for LOE I/II studies, while the MINORS checklist was used for LOE III/IV studies.

RESULTS

Nineteen studies were included for a total of 861 shoulders. Mean age of participants was 48.5 ± 7.4 years. Mean follow-up was 43.8 ± 29.9 months. Four studies reported functional results after conservative treatment, whereas 15 studies were focused on surgical management. No studies directly compared conservative and surgical treatment. Seven studies reported a surgical approach after failure of previous conservative treatment. All studies reported functional improvement and pain relief. Complication rate was low. Overall methodological quality of included studies was very low.

CONCLUSION

Conservative and surgical treatments are both effective in acromioclavicular joint osteoarthritis management. However, available data did not allow to establish the superiority of one technique over another.

LEVEL OF EVIDENCE

Level IV.

The emergency medicine management of clavicle fractures

BACKGROUND

Clavicle fractures are common. An emergency physician needs to understand the diagnostic classifications of clavicle fractures, have a plan for immobilization, identify associated injuries, understand the difference between treating pediatric and adult patients, and have an approach to multimodal pain control. It is also important to understand when expert orthopedic consultation or referral is indicated.

OBJECTIVE OF THE REVIEW

To provide an evidence-based review of clavicle fracture management in the emergency department.

DISCUSSION

Clavicle fractures account for up to 4% of all fractures evaluated in the emergency department. They can be separated into midshaft, distal, and proximal fractures. They are also classified in terms of their degree of displacement, comminution and shortening. Emergent referral is indicated for open fractures, posteriorly displaced proximal fractures, and those with emergent associated injuries. Urgent referral is warranted for fractures with greater than 100% displacement, fractures with >2 cm of shortening, comminuted fractures, unstable distal fractures, and floating shoulder. Nondisplaced or minimally displaced fractures with no instability or associated neurovascular injury are managed non-operatively with a sling. Pediatric fractures are generally managed conservatively, with adolescents older than 9 years-old for girls and 12 years-old for boys being treated using algorithms that are similar to adults.

CONCLUSIONS

When encountering a patient with a clavicle fracture in the emergency department the fracture pattern will help determine whether emergent consultation or urgent referral is indicated. Most patients can be discharged safely with sling immobilization and appropriate outpatient follow-up.

Is conventional radiography still relevant for evaluating the acromioclavicular joint?

INTRODUCTION

Conventional radiography using an anteroposterior view of the acromioclavicular (AC) joint is the gold standard for evaluating arthritic degeneration.

OBJECTIVE

Based on a standardised AP view of the AC joint, the objective of this study was to determine whether this radiographic view is reliable and reproducible for evaluating the AC joint space.

METHODS

A cadaver scapula-clavicle unit, free of osteoarthritis, was used for this study. The scapula was positioned in a stand; and then with fluoroscopy guidance, a strict AP view of the AC joint was taken. Starting from this "0" position, a radiograph was taken by varying the angle by 5°, 10°, and 15° in every plane in space. All radiographs were taken during a single session to ensure the distance between the X-ray tube and scapula did not change. The images were then exported to OsiriX for processing; the superior and inferior AC distance and the joint area were measured.

RESULTS

There was no reproducibility in the AC joint measurements as a function of the incidence angle relative to a strict AP view.

CONCLUSION

Conventional radiography using an AP view of the AC joint cannot be used to do a fine analysis of arthritic degeneration of this joint. It is likely that only CT scan or MRI is sufficient to analyse osteoarthritis in this joint.

LEVEL OF EVIDENCE

IV, basic science study.

A Current Concepts Review of Clavicle Injuries in Ice Hockey From Sternoclavicular to Acromioclavicular Joint

Clavicle injuries are common in ice hockey, and a number of high-profile fractures and dislocations have occurred in elite hockey players in recent years. Acromioclavicular joint injuries, clavicle fractures, and sternoclavicular joint injuries are some of the most frequent hockey-related injuries treated by orthopaedic surgeons, and familiarity with the management of these injuries and sport-specific considerations for treatment and recovery are critical. Injuries involving the clavicle can sometimes be life-threatening, and subtle findings on physical examination and radiographic studies can have profound implications for treatment. The recent literature pertinent to the diagnosis and treatment of clavicle-related injuries in ice hockey players was reviewed and compiled into a clinical commentary. For ice hockey players, the upper extremity was traditionally considered a relatively well-protected area. However, given the evolution of the game and its protective equipment, the upper extremity now accounts for the majority of youth ice hockey injuries, of which clavicle injuries comprise a significant proportion. Acromioclavicular joint injuries are the most common injury in this population, followed closely by clavicle fractures. Sternoclavicular joint injuries are rare but can be associated with serious complications. The treatment of these injuries often differs between athletes and the general population, and surgical indications continue to evolve in both groups. Although the evidence regarding clavicle injuries is ever-increasing and the treatment of these injuries remains controversial, clavicle injuries are increasingly common in ice hockey players. Rule and equipment changes, most notably the increased use of flexible boards and glass, have been shown to significantly decrease the risk of clavicle injuries. We also recommend compulsory use of shoulder pads, even at a recreational level, as well as continued enforcement and evolution of rules aimed at reducing the rate of clavicle injuries. Future research should focus on equipment design changes directed toward clavicle injury prevention, standardized return-to-play protocols, and studies weighing the risks and benefits of nonoperative management of controversial injuries, such as type III acromioclavicular joint dislocations and diaphyseal clavicle fractures.

Imaging of the Acromioclavicular Joint: Anatomy, Function, Pathologic Features, and Treatment

The acromioclavicular joint is an important component of the shoulder girdle; it links the axial skeleton with the upper limb. This joint, a planar diarthrodial articulation between the clavicle and the acromion, contains a meniscus-like fibrous disk that is prone to degeneration. The acromioclavicular capsule and ligaments stabilize the joint in the horizontal direction, while the coracoclavicular ligament complex provides vertical stability. Dynamic stability is afforded by the deltoid and trapezius muscles during clavicular and scapular motion. The acromioclavicular joint is susceptible to a broad spectrum of pathologic entities, traumatic and degenerative disorders being the most common. Acromioclavicular joint injury typically affects young adult males and can be categorized by using the Rockwood classification system as one of six types on the basis of the direction and degree of osseous displacement seen on conventional radiographs. MRI enables the radiologist to more accurately assess the regional soft-tissue structures in the setting of high-grade acromioclavicular separation, helping to guide the surgeon's selection of the appropriate management. Involvement of the acromioclavicular joint and its stabilizing ligaments is also important for understanding and classifying distal clavicle fractures. Other pathologic processes encountered at this joint include degenerative disorders; overuse syndromes; and, less commonly, inflammatory arthritides, infection, metabolic disorders, and developmental malformations. Treatment options for acromioclavicular dysfunction include conservative measures, resection arthroplasty for recalcitrant symptoms, and surgical reconstruction techniques for stabilization after major trauma.

Imaging of Acute Shoulder Trauma

Acute injuries to the shoulder girdle are common and frequently encountered by the practicing radiologist. The type of injury is highly dependent on the age of the patient and mechanism of trauma with injuries occurring at the site of greatest mechanical weakness. In this review, we discuss the main clinical features and key imaging findings for the most common shoulder injuries. For each injury, we also provide a section on the important features that the orthopedic surgeon needs to know in order to guide surgical versus nonsurgical management.

The medium-term results of acromioclavicular joint arthroscopy with chondral and meniscal debridement

PURPOSE

Surgical management of a young patient with a stable but painful acromioclavicular (AC) joint but normal imagining is a challenging problem. A standard arthroscopic excision of distal clavicle seems too aggressive. An alternative procedure is arthroscopic debridement of the joint, particularly the often torn meniscus, and chondroplasty. This study demonstrates in younger patients the medium-term result of arthroscopic debridement of a painful AC joint.

METHODS

Fifty-three young adult patients with a stable but painful AC joint, and virtually normal magnetic resonance imaging (MRI) scan, had arthroscopic debridement of the AC joint. Follow-up was with questionnaire and American Shoulder and Elbow Surgeons Shoulder Score (ASES).

RESULTS

Mean age was 29 years (18-39), 41 male, 31 dominant arm. Twenty-two patients demonstrated additional shoulder pathology. Two patients had a later distal clavicle excision. Five patients had later surgery to other areas of the shoulder but had an asymptomatic AC joint. Thirty-eight patients completed the ASES questionnaire at mean 44 months (24-86) post-operation. The mean ASES score was 82.8 (52-100). There was no association between ASES score and AC joint disease severity found at operation ( p = 0.25). Seven patients had ongoing shoulder symptoms, although none were severe enough to warrant any treatment.

CONCLUSION

In this young group of patients with arthroscopic AC joint debridement, most had good relief of the AC joint related symptoms. This is a worthwhile procedure in the young patient, with quick recovery, and does not preclude further AC joint surgery later.

The relationship of the acromion to the distal clavicle in normal and symptomatic degenerated acromioclavicular joints

INTRODUCTION

Although degenerative osteoarthritis of the acromioclavicular joint is a common finding on technical investigations, not every patient experiences pain or function loss. The difference between symptomatic and asymptomatic patients is currently not elucidated. Therefore, we want to investigate the acromioclavicular relationship in normal, asymptomatic, and symptomatic degenerated ACJ.

MATERIALS AND METHODS

84 normal ACJ, 39 asymptomatic degenerated ACJ, and 30 symptomatic degenerated ACJ were 3D reconstructed. The morphological dimensions and the relationship of the acromion and distal clavicle were measured using computational software. The reproducibility of this technique was evaluated using inter- and intra-observer reliability.

RESULTS

The mean anteroposterior and superoinferior distance of both the clavicle and acromion was significantly larger in asymptomatic and symptomatic degenerative ACJ compared to the normal ACJ (p < 0.001). In symptomatic osteoarthritic ACJ, both the anterior and posterior borders of the acromion were significantly more anterior to the borders of the clavicle than in the normal group and asymptomatic group (p < 0.001). Subsequent ROC curve analysis resulted in a sensitivity of 86.7% and a specificity of 88.6% for anterior subluxation of the ACJ. This technique showed an excellent inter- and intra-observer reliability.

CONCLUSIONS

In patients with degenerative ACJ, both the distal clavicle and acromion are enlarged. In asymptomatic patients, the AC relationship is the same as in normal patients, in contrast, in patients with symptomatic degenerative ACJ, the acromion is subluxated anteriorly compared to the clavicle.

Sports-related sternoclavicular joint injuries

Sports-related injuries to the shoulder are common causes of disability. Injuries to the sternoclavicular joint (SCJ) in sports are more rare, though have been reported in a small number of cases. SCJ injury classification is determined by the degree of joint displacement and direction of clavicular displacement. Direction of displacement is particularly important due to risk of injury to intrathoracic structures, which has the potential to result in fatal outcomes. These injuries are important to identify in athletes and can be difficult to assess on the field. Specific radiographic views and use of ultrasound can improve accuracy of diagnosis. Reduction of acute traumatic SCJ dislocations is recommended and may require open reduction in the case of posteriorly displaced dislocations. Surgical treatment is indicated in cases of persistent pain or significant compression to intrathoracic soft tissue structures. Long-term outcomes are generally favorable, and athletes are able to return to sport without functional limitations.

Injuries of the sternoclavicular region indicate concomitant lesions and need distinguished imaging

PURPOSE

To evaluate injuries of the sternoclavicular region as indicator injury for relevant concomitant injuries and to evaluate the modalities of initial imaging. We hypothesised a high incidence of concomitant injuries as well as a deficiency of X-ray as the initial gold standard.

METHODS

We retrospectively analysed patients suffering from injuries of the sternoclavicular region between 2002 and 2017. We analysed amongst injury type and severity, initial imaging (X-ray vs. CT scan of the sternoclavicular region vs. whole-body scan), and complement of imaging with regard to defined concomitant injury localisations and the resulting necessity and urgency of surgery.

RESULTS

We included n = 61 patients. The mean ISS was 13.5 ± 17, n = 13 (21.3%) cases were classified as "severely injured" (ISS ≥ 16). N = 29 (47.5%) achieved an initial X-ray, n = 10 (16.4%) an initial CT scan of the sternoclavicular region, and n = 22 (36%) an initial whole-body CT scan. Initial imaging correlated significantly with ISS. In n = 21 (72.4%) cases of the X-ray group a significant complement from X-ray to CT scan of the sternoclavicular region was indicated (p ≤ 0.001). N = 31 (50.8%) patients suffered from concomitant injuries. N = 39 (63.9%) of all patients underwent any kind of surgery, thereof n = 23 (37.7%) related to their sternoclavicular injuries.

CONCLUSION

Injuries of the sternoclavicular complex are indicators for the presence of multiple injuries. A CT scan of the sternoclavicular region including ipsilateral apex of the lung and upper rib cage comprised a large proportion of concomitant injuries. Mapping those injuries during initial imaging improves treatment process, avoids underdiagnostic, and decreases uncertainties.

Early Detection of Inflammation and Joint Destruction Revealed by Ultrasound in a Patient with Sternoclavicular Septic Arthritis

A 53-year-old Japanese man experienced fever/neck pain, and neck magnetic resonance imaging revealed a spinal epidural abscess. The following day, he developed a palpable mass with evident inflammatory signs in the right sternoclavicular joint (SCJ) with severe pain. Ultrasound revealed synovitis with remarkable power Doppler signals in the right SCJ. Blood cultures yielded Streptococcus agalactiae growth. After 12 days, ultrasound showed right distal clavicle bone erosion. His symptoms improved with long-term parenteral antibiotic treatment, but the right SCJ joint destruction progressed for several months. We diagnosed him with sternoclavicular septic arthritis complicated with a spinal epidural abscess and bacteremia.

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.

Acromioclavicular Joint Dislocation: Repair Through Open Ligament Transfer and Nonabsorbable Suture Fixation

Acromioclavicular (AC) joint instability is a fairly common and particularly limiting injury that may result in persistent pain and reduced quality of life. In most cases, conservative management is successful. However, in the case of a severe AC joint dislocation, surgical intervention may be warranted. Previous surgical techniques for treatment of AC joint instability include screw fixation between the coracoid and clavicle, coracoacromial ligament transfer from its acromial insertion to the clavicle, and reconstruction of the coracoacromial and/or coracoclavicular ligaments. The purpose of this Technical Note is to describe our preferred technique for the treatment of a high-grade AC dislocation through coracoacromial ligament transfer to the lateral clavicle and nonabsorbable suture fixation between the coracoid process and clavicle.

Arthroscopic Intra-articular Disk Excision of the Sternoclavicular Joint

The sternoclavicular joint (SCJ) has a complete intra-articular disk that can be damaged either as a result of trauma or as part of ongoing degenerative joint disease. Although often asymptomatic, SCJ disk tears may lead to mechanical symptoms and pain. Previously, isolated symptomatic SCJ disk tears have only occasionally been mentioned in the literature with a few associated case reports of diskectomy by open arthrotomy. With improved imaging and availability of magnetic resonance imaging scans and the advent of SCJ arthroscopy it is now possible to treat symptomatic SCJ disk tears by arthroscopic excision. In this Technical Note, we describe the diagnosis of a torn SCJ disk and the technique of arthroscopic excision of a torn SCJ disk.

Bipolar Dislocation of the Clavicle: A Report of Two Cases with Different Injury Patterns and a Literature Review

Bipolar dislocation of the clavicle is a rare injury that is defined as a concomitant dislocation of the ipsilateral acromioclavicular joint and sternoclavicular joint. This injury is also described as a floating clavicle. Although this injury has been known for nearly two centuries, knowledge about it is limited and the treatment strategy remains controversial. Bipolar dislocation includes several combinations of both joints' injury types. We reported two patients with bipolar dislocation of the clavicle: one with an anterior dislocation and the other with a posterior dislocation of the sternoclavicular joint. After reviewing the currently available literature, we discussed these cases to highlight the necessity of a specific treatment approach that is modified based on the pattern of each joint's lesion.

Shoulder acromioclavicular joint reconstruction options and outcomes

Acromioclavicular joint separations are a common cause of shoulder pain in the young athletic population. In high-grade injuries, acromioclavicular joint reconstruction procedures may be indicated for functional improvement. There is currently no gold standard for the surgical management of these injuries. Multiple reconstructive options exist, including coracoclavicular screws, hook plates, endobutton coracoclavicular fixations, and anatomic ligament reconstructions with tendon grafts. This article aims to review pertinent acromioclavicular joint anatomy and biomechanics, radiographic evaluation, classification system, as well as reconstruction options, outcomes, and complications.

Pediatric Posterior Sternoclavicular Joint Injuries

Posterior sternoclavicular joint injuries are increasingly diagnosed in children and young adults. Most of these injuries are the result of indirect mechanisms, typically lateral compression, with a posterior-to-anterior force applied to the shoulder during sports. Less frequently, these injuries are caused by direct impact on the medial clavicle, which can occur in rollover motor vehicle accidents, or may represent atraumatic instability. In patients younger than 25 years, physeal separation is more common than true dislocation. Theoretically, these patients have increased remodeling potential. Reduction is recommended to prevent and/or manage the compression of mediastinal structures, which can lead to life-threatening injury. Open surgical stabilization is the preferred treatment for acute and chronic retrosternal injuries. A thoracic or trauma surgeon should be available during stabilization in the rare event of potentially life-threatening hemorrhage after reduction. Outcomes have been largely successful, with pain-free, unrestricted range of motion and return to activity.

A Case of Posterior Sternoclavicular Dislocation in a Professional American Football Player

Sternoclavicular (SC) dislocation is a rare injury of the upper extremity. Treatment of posterior SC dislocation ranges from conservative (closed reduction) to operative (open reduction with or without surgical reconstruction of the SC joint). To date, we are unaware of any literature that exists pertaining to this injury or its treatment in elite athletes. The purpose of this case report is to describe a posterior SC joint dislocation in a professional American football player and to illustrate the issues associated with its diagnosis and treatment and the athlete’s return to sports. To our knowledge, this case is the first reported in a professional athlete. He was treated successfully with closed reduction and returned to play within 5 weeks of injury.

Evidence-based practice: best imaging practice in musculoskeletal disorders

As musculoskeletal disorders are a common cause of emergency department visits in the United States, it is vital for nurses and nurse practitioners to understand the decision rules for ordering imaging tests when triaging patients with musculoskeletal complaints. Proper knowledge and command of selecting the most appropriate imaging for these frequent emergency department presentations will help reduce costs, decrease ionizing radiation exposure, and increase patient throughput. This article reviews the current evidence-based literature for musculoskeletal imaging in the emergency department and discusses the epidemiology, etiology, management, and prevention of the most common musculoskeletal disorders.

A novel radiographic index for the diagnosis of posterior acromioclavicular joint dislocations

BACKGROUND

Posterior acromioclavicular (AC) joint dislocations are frequently misclassified because posterior translation of the clavicle is difficult to evaluate in Zanca radiograph views. A novel radiographic index was used in this study to accurately diagnose posterior dislocations of the AC joint.

HYPOTHESIS

This novel index has a high degree of accuracy for the diagnosis of posterior AC joint dislocations.

STUDY DESIGN

Cohort study (diagnosis); Level of evidence, 2.

METHODS

This was an analytic, descriptive study of 150 patients with different grades of AC injuries according to the Rockwood classification (30 patients for each grade of injury: I, II, III, IV, and V). The diagnosis of an AC injury was made both clinically and radiographically by using comparative Zanca and axillary views. Two measurements were performed in Zanca views: the coracoclavicular distance and the AC width distance. A width index was calculated for each patient. The Student t test, Bonferroni test, logistic regression, linear regression, and receiver operating characteristic (ROC) curves were used for statistical analysis. Forty cases were impartially selected to obtain a κ concordance value.

RESULTS

The average value of the AC width index per group (according to the Rockwood classification) was as follows: type I, 2.1% (range, -12% to 25%); type II, 4.2% (range, -19% to 29%); type III, 19.1% (range, -59% to 91%); type IV, 110.3% (range, 47% to 181%); and type V, -3.8% (range, -71% to 62%). There was a significant difference between the average width index in the patients with type IV injuries and those in the remaining groups (P < .05). The ROC curve showed that a width index of 60% has a sensitivity of 95.7% and specificity of 97.5%, with a positive predictive value of 96.7% and negative predictive value of 95.6% to predict a type IV injury. Intraobserver reliability was rated as substantial agreement for each of 3 observers; the interobserver reliability of the 3 independent raters was almost perfect.

CONCLUSION

An AC width index of ≥60% is highly accurate for the diagnosis of a posterior AC joint dislocation, with high intraobserver and interobserver concordance.

Standard axillary radiographs of the shoulder may mimic posterior subluxation of the lateral end of the clavicle

OBJECTIVES

On standard axillary radiographs of normal shoulders, the clavicle may appear subluxated posteriorly. This subluxation might be viewed as an indication for surgical stabilization in acromioclavicular (AC) injury. The purpose of this study was to assess the reliability of identification of anteroposterior displacements of the AC joint on standard axillary radiographs of the human shoulder.

METHODS

We performed 170 radiographs of the AC joint in 10 cadaveric shoulders using various projection angles. The distance from the anterior margin of the acromion to the distal clavicle was measured to identify an "optimal" view to image the true anteroposterior alignment of normal AC joints.

RESULTS

On the standard axillary view of intact shoulders, we found an average posterior translation of 1.7 mm (range, -3 to 7; SD, 2.8) and of 0.9 mm (range, -5 to 5; SD, 2.8) in an "optimal view," tilted 15 degees dorsal and 15 degees lateral.

CONCLUSIONS

The standard axillary radiograph has a very high sensitivity but poor accuracy in identifying a posterior clavicular translation in the AC joint. We could not identify a reliable modification of the axillary radiographic projection to improve the accuracy. Therefore, an apparent posterior subluxation of the clavicle identified on an axillary radiograph is more likely a false positive finding than an identification of a true pathology.

Degenerative joint disease of the acromioclavicular joint: a review

Osteoarthritis of the acromioclavicular (AC) joint is a common condition causing anterior or superior shoulder pain, especially with overhead and cross-body activities. This most commonly occurs in middle-aged individuals because of degeneration to the fibrocartilaginous disk that cushions the articulations. Diagnosis relies on history, physical examination, imaging, and diagnostic local anesthetic injection. Diagnosis can be challenging given the lack of specificity with positive physical examination findings and the variable nature of AC joint pain. Of note, symptomatic AC osteoarthritis must be differentiated from instability and subtle instability, which may have similar symptoms. Although plain radiographs can reveal degeneration, diagnosis cannot be based on this alone because similar radiographic findings can be seen in asymptomatic individuals. Nonoperative therapy can provide symptomatic relief, whereas patients with persistent symptoms can be considered for resection arthroplasty by open or arthroscopic technique. Both techniques have proven to provide predictable pain relief; however, each has its own unique set of potential complications that may be minimized with an improved understanding of the anatomical and biomechanical characteristics of the joint along with meticulous surgical technique.

Novel assessment of the sternoclavicular joint with computed tomography for planning interventional approach

OBJECTIVES

To describe the plane of the sternoclavicular joint (SCJ) to aid planning of instrument orientation during invasive procedures.

METHODS

Computed tomography (CT) images of 80 consecutive patients aged 25 to 40 years with appropriate chest imaging series were retrospectively reviewed. Patients with a previous median sternotomy, fused manubriosternal joint or fracture were excluded. The medial clavicle was found to vary greatly in its anatomy such that a representative morphology could not be described. The manubrium was found to be a more consistent structure and was examined in more detail. The angulation of the SCJ was measured in three orthogonal planes using CT multiplanar reformats. Each SCJ (160 in total) was assessed for transverse, coronal, and sagittal angulation of the central manubrial articular surface in respect to the long axis of the manubrial body using a newly devised measurement technique.

RESULTS

The mean angles (± standard deviation) of the SCJs were 62.4 ± 9.7° to the transverse plane, 149.3 ± 7.3° to the coronal plane and 69.8 ± 7.5 to the sagittal plane. There was no significant difference in transverse (p = 0.41) or sagittal (p = 0.60) angulation between sides, however there was a significant difference for the coronal plane (p = 0.04). No significant differences were noted between the sexes in any plane.

CONCLUSIONS

Increasing use of invasive diagnostic and treatment techniques dictate that a safe approach to the joint should be used to reduce the risk of iatrogenic injury. This study adds to existing knowledge of SCJ anatomy and its variation within the population. Understanding this can minimize the risk to adjacent structures when approaching the SCJ with injection needles or arthroscopic instruments.

Localization of degenerative changes of the acromioclavicular joint: a cadaveric study

PURPOSE

It has not been fully clarified yet how degenerative changes occur within the acromioclavicular (AC) joint, including their localizations. The aim of this study was to clarify the localization of degenerative changes in the AC joint using cadaveric specimens.

METHODS

Thirty-eight cadaveric AC joints with the sections were cut in the coronal plane. For both the acromion and the clavicle, the joint surface was divided into upper and lower halves. Histological features including the mean thickness of cartilage, reduction of proteoglycan staining and the extent of damaged tidemark were evaluated. The shapes of intraarticular discs as well as their histological structures were also assessed, which were compared between the upper and lower halves.

RESULTS

Articular cartilage in the lower half was significantly thinner than that in the upper half for both the acromion and the clavicle (p < 0.01). Similarly, the lower half of cartilage was more degenerated than the upper half. Intraarticular discs were absent in nine joints and the meniscoid-like type in 29, which contained rich fibrocartilaginous tissues in the upper half, whereas it mainly consisted of the fibrous tissues with granulation in the lower half.

CONCLUSION

The lower half of the AC joint demonstrated more advanced degeneration than the upper half, which might reflect the greater repetitive mechanical stress. The present study revealed both the localization and the extent of degenerative changes in AC joint, which might be useful information for surgeons to determine the proper amount of bony resection in the surgical treatment for osteoarthritis of this joint.

Anterior Chest Wall Involvement in Early Stages of Spondyloarthritis: Advanced Diagnostic Tools

Objective.

Anterior chest wall (ACW) involvement is difficult to evaluate in patients with spondyloarthritis (SpA). Bone scan is sensitive to ACW involvement, while magnetic resonance imaging (MRI) detects early alterations in SpA. We compared the sensitivity and specificity of bone scans and MRI in assessing ACW in early SpA.

Methods.

Out of 110 patients with early SpA attending the Outpatient Rheumatology Unit Clinic of Padua University from January 2008 to December 2010, the 40 complaining of pain and/or tenderness [60% with psoriatic arthritis (PsA), 12.5% with ankylosing spondylitis, and 27.5% with undifferentiated SpA] underwent bone scans and MRI.

Results.

At clinical examination, sternocostoclavicular joints were involved in 87.5% on the right, 77.5% on the left, and 35% on the sternum. Bone scan was positive in 100% and MRI in 62.5% of these patients. Early MRI signs (bone edema, synovial hyperemia) were observed in 27.5%, swelling in 5%, capsular structure thickness in 37.5%, erosions in 15%, bone irregularities in 15%, osteoproductive processes in 12.5%, and osteophytes in 5%. A higher prevalence of Cw6, Cw7, B35, and B38 was found in 15%, 48%, 28%, and 12%, respectively, of the patients with PsA who had bone scans.

Conclusion.

Noted mainly in women, ACW involvement was frequent in early SpA. Both bone scans and MRI are useful in investigating ACW inflammation. Bone scans were found to have high sensitivity in revealing subclinical involvement, but a low specificity. MRI provides useful information for therapeutic decision making because it reveals the type and extent of the process. The significant associations of HLA-Cw6 and Cw7 with PsA could suggest that genetic factors influence ACW involvement.

Acromioclavicular joint injuries and reconstructions: a review of expected imaging findings and potential complications

Shoulder injuries, including acromioclavicular (AC) joint separations, remain a common reason for presentation to the emergency room. Although the diagnosis can be made apparent through proper history and physical examination by the emergency medicine physician, ascertaining the degree of injury can be difficult on the basis of clinical evaluation alone. While there is consensus in the literature that low-grade AC joint injuries can be treated with conservative management, high-grade injuries will generally require surgical intervention. Furthermore, the treatment of grade 3 injuries remains controversial, making it incumbent upon the radiologist to become comfortable with distinguishing this diagnosis from lower or higher grade injuries. Imaging of AC joint injuries after clinical evaluation is generally initiated in the emergency room setting with plain film radiography; however, on occasion, an alternative modality may be presented to the emergency room radiologist for interpretation. As such, it remains important to be familiar with the appearance of AC joint separations on a variety of modalities. Another possible patient presentation in both the emergent and nonemergent setting includes new onset of pain or instability in the postsurgical shoulder. In this scenario, the onus is often placed on the radiologist to determine whether the pain or instability represents the sequelae of reinjury versus a complication of surgery. The purpose of this review is to present an anatomically based discussion of imaging findings associated with AC joint separations as seen on multiple modalities, as well as to describe and elucidate a variety of potential complications which may present to the emergency room radiologist.

MRI versus radiography of acromioclavicular joint dislocation

OBJECTIVE

Acromioclavicular joint injuries are usually diagnosed by clinical and radiographic assessment with the Rockwood classification, which is crucial for treatment planning. In view of the implementation of MRI for visualization of the acromioclavicular joint, the purpose of this study was to describe the MRI findings of acromioclavicular joint dislocation in comparison with the radiographic findings.

SUBJECTS AND METHODS

Forty-four patients with suspected unilateral acromioclavicular joint dislocation after acute trauma were enrolled in this prospective study. All patients underwent digital radiography and 1-T MRI with a surface phased-array coil. MRI included coronal proton density-weighted turbo spin-echo and coronal 3D T1-weighted fast field-echo water-selective sequences. The Rockwood classification was used to assess acromioclavicular joint injuries at radiography and MRI. An adapted Rockwood classification was used for MRI evaluation of the acromioclavicular joint ligaments. The classifications of acromioclavicular joint dislocations diagnosed with radiography and MRI were compared.

RESULTS

Among 44 patients with Rockwood type I-IV injuries on radiographs, classification on radiographs and MR images was concordant in 23 (52.2%) patients. At MRI, the injury was reclassified to a less severe type in 16 (36.4%) patients and to a more severe type in five (11.4%) patients. Compared with the findings according to the original Rockwood system, with the adapted system that included MRI findings, additional ligamentous lesions were found in 11 (25%) patients.

CONCLUSION

In a considerable number of patients, the MRI findings change the Rockwood type determined with radiography. In addition to clinical assessment and radiography, MRI may yield important findings on ligaments that may influence management.

Posterior dislocation of sternoclavicular joint encroaching on ipsilateral vessels in 2 pediatric patients

Dislocation of the sternoclavicular joint (DSCJ) with posterior displacement of the clavicle is uncommon in children. This can lead to ipsilateral compression of the great vessels. Diagnosis may not be apparent on routine radiographs. Axial computed tomographic (CT) scan is the imaging of choice for diagnosis. Reconstruction and 3-dimensional (3D) views on CT scan may be helpful to define the anatomy before surgical reduction. We present 2 patients who had traumatic posterior DSCJ with compromise to their vascular structures. Patient 1 was a 13-year-old boy with posterior DSCJ on his left side that was not apparent on x-ray and that was diagnosed to have encroachment of the medial end of the clavicle on the left brachiocephalic vein on CT scan. Reconstruction and 3D views on CT scan were helpful in defining the anatomy before surgical reduction. The patient underwent emergent open reduction and internal fixation with complete recovery.Patient 2 was a 14-year-old boy with posterior DSCJ on the right side that was apparent on x-ray and was evaluated to have encroachment of the medial end of the clavicle on the right innominate artery with an associated paratracheal hematoma on CT scan. Reconstruction and 3D views on CT scan were also helpful in defining the anatomy before surgical reduction. The patient underwent a successful closed reduction with complete recovery.

Ultrasonography of the shoulder

The shoulder is the most common region to be evaluated with musculoskeletal ultrasound. The shoulder's complex anatomy enables an exceptional range of mobility at the expense of static stability. Consequently, the shoulder is susceptible to a multitude of traumatic and atraumatic injuries. This article presents an overview of shoulder anatomy, recommends a standardized approach to the sonographic shoulder evaluation, and discusses common sonographically apparent pathology of the shoulder.

Surgical treatment for acromioclavicular joint osteoarthritis: patient selection, surgical options, complications, and outcome

Osteoarthritis is one of the most common causes of pain originating from the acromioclavicular (AC) joint. An awareness of appropriate diagnostic techniques is necessary in order to localize clinical symptoms to the AC joint. Initial treatments for AC joint osteoarthritis, which include non-steroidal anti-inflammatory drugs (NSAIDS) and corticosteroids, are recommended prior to surgical interventions. Distal clavicle excision, the main surgical treatment option, can be performed by various surgical approaches, such as open procedures, direct arthroscopic, and indirect arthroscopic techniques. When choosing the best surgical option, factors such as avoidance of AC ligament damage, clavicular instability, and post-operative pain must be considered. This article examines patient selection, complications, and outcomes of surgical treatment options for AC joint osteoarthritis.

The sternoclavicular joint: can imaging differentiate infection from degenerative change?

OBJECTIVE

The purpose of this study was to determine if there are imaging and clinical findings that can differentiate a septic sternoclavicular joint from a degenerative one.

MATERIALS AND METHODS

Search of radiology reports from 2000-2007 revealed 460 subjects with imaging of the sternoclavicular joint, of whom 38 had undergone aspiration or biopsy. The final study group consisted of nine subjects with pathologic proof of sternoclavicular joint infection and ten subjects with pathologic and clinical findings excluding infection consistent with degenerative change. Available ultrasound, computed tomography (CT), and magnetic resonance (MR) images were retrospectively reviewed, and echogenicity, capsular distention, erosions, cysts, hyperemia or enhancement, and intensity of bone marrow signal were recorded. Clinical data were also reviewed.

FINDINGS

The findings significantly associated with sternoclavicular joint infection included degree and extent of capsular distention. With infection, average joint distention was 14 mm (range 10-20 mm) and extended over the sternum and clavicle in 60% compared to 5 mm (range 3-8 mm) with degeneration only extending over the clavicle. Other findings significantly associated with infection included bone marrow fluid signal on magnetic resonance imaging (MRI), elevated Westergren red blood cell sedimentation rate, and fever. The two findings significantly associated with degeneration were subchondral cysts on CT and female gender. Other imaging and clinical variables showed no significant differences between infection and degenerative change.

CONCLUSION

The clinical and imaging findings significantly associated with sternoclavicular joint infection included joint capsule distention of 10 mm or greater, extension over both the clavicle and sternum, adjacent fluid signal bone marrow replacement, elevated Westergren red blood cell sedimentation rate, and fever.

Dynamic radiologic evaluation of horizontal instability in acute acromioclavicular joint dislocations

BACKGROUND

Biplane radiologic evaluation is indispensable for the correct diagnosis of acute acromioclavicular (AC) joint injuries. Thus far, no functional radiographic techniques have been quantified to evaluate horizontal instability in acute AC joint dislocations.

HYPOTHESIS

Supine dynamic axillary lateral shoulder views detect horizontal instability of the distal clavicle in patients with acute AC joint dislocations.

STUDY DESIGN

Cohort study (Diagnosis); Level of evidence, 2.

METHODS

Twenty-five consecutive patients with a mean age of 39 +/- 14 years with acute AC joint injury underwent biplane radiologic evaluation, including a conventional Zanca view and an axillary lateral view in a sitting position. In addition, supine axillary lateral views with the arm in 90 degrees of abduction and 60 degrees of flexion and extension were taken to evaluate the horizontal dynamics of the distal clavicle. The gleno-acromio-clavicular angle (GACA) was introduced and used to quantify the horizontal clavicular dynamics in terms of angle differences. The unaffected shoulders served as the control group.

RESULTS

Superior dislocation of the lateral clavicle in the Zanca view was classified as Rockwood type II in 7 patients, type III in 15, and type V in 3. The axillary lateral view in a sitting position showed posterior dislocation of the distal clavicle in 8 patients (Rockwood type IV injury). Dynamic radiologic evaluation revealed an average GACA difference between the neutral and anterior position of the arm of 7.1 degrees +/- 5.5 degrees for the unaffected shoulder. In the injured AC joints, 11 patients showed no radiologic evidence of horizontal instability (group A) with a GACA difference of 7.1 degrees +/- 4.8 degrees . Increased anteroposterior translation was evident in 14 patients (group B) with a GACA difference of 30.3 degrees +/- 14.3 degrees (P < .001).

CONCLUSION

Functional axillary radiologic evaluation seems to represent a simple imaging tool to reveal dynamic horizontal instability.

CLINICAL RELEVANCE

Horizontal instability of the distal clavicle in acute AC joint injuries represents an indication for surgical treatment. Dynamic axillary radiologic evaluation may detect previously missed unstable injuries. This evaluation might be relevant when deciding on surgical AC joint stabilization.

Sternoclavicular joint injuries

Sternoclavicular joint (SCJ) injuries are uncommon, but delay in diagnosis and treatment can result in significant morbidity. This review outlines the relevant clinical anatomy and biomechanics of the joint, and examines the evidence supporting specific investigation and management of such injuries.

Long-term outcome after joint reconstruction or medial resection arthroplasty for anterior SCJ instability

INTRODUCTION

In the present study, the long-term results of 11 patients with anterior sternoclavicular joint (SCJ) instability are reported. All included patients had an anterior SCJ instability and due to delayed diagnosis, operative treatment was not done immediately.

METHOD

The patients had a mean age of 29.2 years (range 16-63 years). One patient sustained concomitant injuries. Six patients had resection arthroplasty. Five patients had reconstruction of the SCJ with transosseous tension band PDS fixation or ligament reconstruction with additional wire cerclage. The results of treatment were evaluated after a mean follow-up period of 9.9 years (range 1-27 years) using the ASES, DASH and power-, age and gender adjusted Constant-Murley Score.

RESULTS

In general, the mean values of the different scores (ASES 79.8; DASH 11.8; Constant-Murley 81%) demonstrated good outcome. The outcome evaluation of the patients who had SCJ reconstruction did not differ significantly from the patients who had medial resection arthroplasty. The rate of postoperative pain or instability was low using visual analog scale and did not differ significantly between the groups. The outcome results of the reconstruction group were equal to the results of the resection group when SCJ-reconstruction was performed soon after SCJ injury. One patient in the resection group (6 patients) demonstrated poor results due to continued instability of the remaining clavicle.

CONCLUSION

We concluded that patient selection and a specific clinical indication for operative treatment are crucial. Resection of the medial clavicle results in good functional outcome when the costoclavicular ligament is preserved or reconstructed.

Variations in normal sternoclavicular joints; a retrospective study to quantify SCJ asymmetry

OBJECTIVE

A wide degree of normal anatomical variation can occur at the sternoclavicular joint (SCJ). On occasion, this has led to concern for a pathological process, potentially resulting in a costly work-up, unnecessary patient worry and invasive diagnostic procedures such as biopsy. The purpose of this study was to determine the normal range of anatomical variation at sternoclavicular joints.

MATERIALS AND METHODS

One hundred four consecutive patients with chest CT done at our institution were selected. Patients with clear SCJ pathology, chest wall abnormality, CT slice thickness greater than 5 mm and sternotomy wires, were excluded. Chart review was done and showed no SCJ symptoms/signs. We measured the SCJ space, maximum clavicular head diameter within the joint and the distance from manubrium to the anterior margin of the clavicular head.

RESULTS

Left and right SCJ space ranged from 0.2 to 1.37 cm. The difference (delta or asymmetry) between left SCJ space and right SCJ space ranged from 0 (symmetrical) to 0.57 cm in 104 cases. Left and right clavicular head diameter ranged from 1.2 to 3.7 cm with left/right asymmetry (delta) ranging from 0 (symmetrical) to 1 cm. Manubrium to anterior margin of clavicular head ranged from 0.1 to 2.13 cm with delta ranging from 0 to 0.8 cm. Thirty-three patients demonstrated gas in the joint, five had poor articulation and four had calcification in the joint.

CONCLUSION

Greater than 10% of patients show substantial asymmetry in the sternoclavicular joints, which may be misinterpreted as pathological. Gas in the joint is a common phenomenon therefore should not be an indication for further work-up in asymptomatic patients and likely excludes the presence of effusion.

Treatment of chest wall implosion injuries without thoracotomy: technique and clinical outcomes

BACKGROUND

Chest wall implosion injuries secondary to side impact are unusual but devastating injuries. The purpose of this series is to describe the clinical entity, present a surgical technique to reduce and repair the thoracic cage deformity without thoracotomy, and report outcomes in nine patients.

STUDY

Institutional review board approved retrospective case series, surgical technique.

SETTING

Level I Trauma Center.

METHODS

Twenty-two patients were admitted during 7-year period with thoracic cage implosion injuries and multiple segmental rib fractures from a side impact mechanism. All patients' required mechanical ventilation and had an implosion deformity along the posterolateral thoracic cage, pulmonary contusion, and clavicular fractures. Nine patients underwent repair of rib fractures through a paramidline posterior approach without thoracotomy using standard 2.4-mm titanium plates. Seven patients with similar fracture pattern treated nonoperatively were used as a historical control. Total intubation time, intensive care unit (ICU) length of stay (LOS), and final shoulder function using the Constant Murley scoring system were compared between the two groups.

RESULTS

Average age, male to female ratio, and injury severe score were comparable for both cohorts (p > 0.6). Average follow-up was 16 months versus 12 months for the operative and nonoperative groups, respectively, (p = 0.11). In the operative group, 8 of 9 (89%) patients were extubated within 24 hours of surgery; 3 of 9 (33%) were extubated in the operating room. In the operative group, seven patients underwent internal fixation of the clavicle and progressed to union with a mean Constant score of 93. Nine patients had nonoperative treatment of the clavicle with a mean Constant score of 75 (p = 0.04). Total intubation time (1.9 days) was significantly shorter in the operative group than the nonoperative controls at 13.3 days (p < 0.01) and length of ICU stay was also shortened at 5.7 (4-8) days versus 16.7 (10-26) days, respectively, (p < 0.01).

CONCLUSION

Chest wall implosion injuries with fixed deformities of the thoracic cage, multiple segmental rib fractures, and clavicular injury are a distinct clinical entity, which can be effectively managed with a posterior paramidline approach without thoracotomy. Reduction of the deformity and repair of the rib fractures led to a dramatic reduction in time to extubation, ICU LOS, and in-hospital complications including pneumonia and sepsis. Repair of the clavicular fracture appeared to be beneficial.