Coracoid process fractures: anatomy, injury patterns, multimodality imaging, and approach to management

Arthroscopy-assisted procedure provides less residual horizontal instability and optimal coracoid tunnel creation with less radiation exposure compared to percutaneous procedure after endo-button fixation of type III AC joint dislocations

PURPOSE

The aim of this study was to evaluate the postoperative radiological and functional results of patients treated with arthroscopy-assisted (AA) and percutaneous (P) procedures using endo-button for type III acromioclavicular joint dislocations with a minimum 1-year follow-up. The study hypothesis was that the AA technique would provide more favourable coracoid tunnels.

METHODS

This retrospective study included patients who underwent surgery between 2017 and 2022. Computed tomography images taken immediately postoperatively of all the patients were analysed to group coracoid tunnels as optimal or suboptimal based on orientation and placement within the coracoid base. Residual horizontal instability was assessed using the bilateral Alexander view at the final follow-up. Shoulder functions were evaluated at the final follow-up examination.

RESULTS

Of the 63 patients, 39 underwent surgery using the percutaneous procedure and 24 with the AA procedure. Surgical duration was significantly longer in the AA group (AA: 61.1 ± 5.9 min; P: 34.7 ± 5.6 min) (p = 0.001; 95% confidence interval [CI]: 23.3-29.3), whereas fluoroscopy time was longer in the percutaneous group (AA: 2.0 ± 0.8 s; P: 15.7 ± 3.9 s) (p = 0.001; 95% CI: -14.9 to 12.3). Optimal coracoid tunnels were more frequently observed in the AA group (p = 0.001; 95% CI: 7.4-137.8). There was no significant difference in functional scores between the groups (n.s.). Postoperative horizontal instability was more common in the percutaneous procedure (p = 0.013; 95% CI: 8.3-39.2).

CONCLUSIONS

Although no difference was detected between the methods in terms of complications and functional results, the higher frequency of residual horizontal instability, the high risk of suboptimal tunnel creation and greater radiation exposure were seen to be the most important disadvantages of the percutaneous technique. During surgery, such technical problems related to the percutaneous method should be kept in mind and care should be taken about the orientation of the coracoid tunnel.

LEVEL OF EVIDENCE

Level III.

The X-Mas Box Osteosuture: A New Technique for Coracoid Process Fracture

A fracture of the tip of the coracoid is a rare but challenging fracture. A surgical indication is required in case of a displaced fracture. Screws and suture anchors often do not offer a reliable fixation in the case of very small fragments. We describe our hardwareless technique that consists of an osteosuture with a 90-degree suture threads configuration that we called the x-mas box technique. This procedure is cost-effective and it provides stable fixation and low complications rate.

Bilateral insufficiency fracture of coracoid process: A rare case report

A 69-year-old man was admitted to the hospital for a left femoral neck fracture. A preliminary chest computed tomography scan showed no coracoid process fracture. The patient had no history of trauma during his hospitalization. However, subsequent in-hospital computed tomography scan revealed bilateral coracoid process fracture. The patient underwent hip replacement surgery for femoral neck fracture, while conservative treatment was administered for the bilateral coracoid process fracture. After 1-year follow-up, the patient was diagnosed with bilateral insufficiency fracture of coracoid process after ruling out other types of fractures. The fractures did not heal while functions in both shoulders were adequate. Insufficiency fracture should be considered when fractures occur without trauma, especially in the presence of associated risk factors such as chronic renal failure and osteoporosis. For bilateral insufficiency fracture of coracoid process, conservative treatment is acceptable.

Nonunion of the Coracoid Base Secondary to Cutibacterium acnes Infection in a Surgically Naive Patient: A Case Report

CASE

We present the case of a 42-year-old man with a coracoid base fracture that progressed to nonunion. The patient underwent percutaneous autologous bone-marrow and demineralized bone matrix (DBM) grafting 8 months after injury, with all intraoperative cultures positive for Cutibacterium acnes. The patient had no prior surgeries, but he began shaving his axillae around the time of injury. He was treated with amoxicillin; by the 6-week follow-up, computed tomography demonstrated complete fracture healing.

CONCLUSION

Our case demonstrates a novel etiology of coracoid nonunion treated successfully by eradicating the infection with biologic augmentation by percutaneous autologous bone-marrow grafting with DBM and oral antibiotics.

Scapula revisited: new features identified and denoted by terms using consensus method of Delphi and taxonomy panel to be implemented in radiologic and surgical practice

BACKGROUND

The scapular structures that have not yet been assigned anatomic terms generate a challenge in clinical diagnostics and surgical application, as well as in scientific observation. The aim of this study was to solve the lack in terminology concerning the scapula and the scapular region.

METHODS

Observation and description of 29 structures were carried out on both dry scapulae and radiographs of the shoulder joint. In addition, several terms commonly encountered throughout the literature concerning the scapula were revised. A degree of consensus was reached by using the Delphi method surveying the opinions of 21 invited experts in the field. Taxonomy panels and etymology of anatomic terminology were considered in the generation of the proposed terms.

RESULTS

The scapula was redefined as a lamina with projecting processes, and several landmarks demarcating certain newly defined topographic spaces were highlighted via 2 rounds of Delphi systematic voting and discussion. The overall level of the peer nominees' consensus was high. Few terms received a neutral opinion.

CONCLUSIONS

This study communicates a proposal of 16 new terms defining grossly visible structures on the scapula that have not yet been described by officially recognized terms, including a call to unify 13 previously contributed terms that have not been codified and are often used interchangeably within different surgical and scientific fields. Incorporating these terms into the anatomic nomenclature would facilitate communication accuracy and eliminate ambiguity among clinicians, surgeons, and anatomists.

Imaging of traumatic shoulder injuries – Understanding the surgeon’s perspective

Imaging plays a key role in the assessment and management of traumatic shoulder injuries, and it is important to understand how the imaging details help guide orthopedic surgeons in determining the role for surgical treatment. Imaging is also crucial in preoperative planning, the longitudinal assessment after surgery and the identification of complications after treatment. This review discusses the mechanisms of injury, key imaging findings, therapeutic options and associated complications for the most common shoulder injuries, tailored to the orthopedic surgeon’s perspective.

Rare coracoid fractures presenting with superior shoulder suspensory complex injury: A case series

Although coracoid fractures are rare fractures, their treatment is critical as they form the coracoacromial arch and superior shoulder suspensory complex (SSSC), which are important structures for shoulder biomechanics. In this case series, clinical, radiological, and demographic characteristics of three male patients who received treatment due to coracoid fracture presenting with traumatic injuries were discussed. The fractures were classified according to the Ogawa and Eyres classifications, and fracture fixation was achieved surgically with the cannulated screws. All patients had a right coracoid fracture. The Constant-Murley Score and the Disabilities of the Arm, Shoulder and Hand scores the patients in the final follow-up visit at 12 months were calculated. In conclusion, good clinical and functional outcomes can be achieved by anatomical reduction and fixation through surgery for displaced coracoid fractures presenting with multiple traumatic injuries located in multiple regions of the SSSC.

Radiographic and clinical characterization of coracoid fractures: a retrospective cohort analysis

PURPOSE

Coracoid fracture is a rare injury. The aim of this study is to present the demographics, clinical and radiologic characteristics, and outcomes of coracoid fracture in a cohort of 32 patients.

METHODS

We queried our institutional electronic medical record database (years 2012-2020) to identify patients with coracoid fractures using specific International Classification of Disease-10 codes. Demographic data, injury details including mechanism of injury and associated injuries, imaging performed, and treatment outcomes were obtained from retrospective chart review. A radiologist reviewed all available imaging studies (radiographs/CT/MRI) and classified the fractures according to Ogawa and Eyres classifications. Missed diagnoses were determined by comparing initial imaging reports with the follow-up imaging obtained in the office.

RESULTS

Thirty-two patients with coracoid fractures were identified during the study period. Sixteen fractures (50%) occurred in the setting of low-energy trauma. Twelve fractures were missed on initial radiographs, and diagnosis with three-view radiographs (AP, scapular-Y and axillary) was 88% compared to 33% (p < 0.03) with two views (AP, scapular-Y). The majority of fractures were non-displaced (94%), and 56% were Ogawa Type-II fractures. Associated injuries were seen in 81% of patients. Most fractures (94%) were treated without surgery with excellent outcomes.

CONCLUSION

Coracoid fractures continue to be a rare injury. In contrast to previous studies, in this case series of 32 patients, half of the fractures were associated with low-energy trauma, which correlated with higher percentage of non-displaced fractures and Ogawa Type-II fractures. Addition of the axillary view in the trauma radiographic series significantly improved the initial fracture detection rate.

LEVEL IV

Retrospective study.

Rare isolated coracoid mid-process fracture with displacement in an adolescent: Case report

Isolated coracoid fractures (ICFs) are rare and the management is controversial. In this article, we report a displaced ICF, treated conservatively with success. A 12-year-old male patient presented with mild pain in his right shoulder after simple fall. Physical examination was normal except mild tenderness on the coracoid process and mildly limited active shoulder motion. Plain radiographs did not demonstrate any apparent finding of pathology. Computed tomography (CT) images revealed isolated coracoid mid-process fracture with displacement. Significant symptomatic relief as well as sufficient callus formation, confirmed by follow-up CT examination, was achieved after Velpeau sling use for four weeks. After a follow-up duration of 14 months, excellent clinical and radiologic outcomes were accomplished. The result of this case supports the efficiency of conservative treatment for ICFs in adolescents, even in the presence of considerable fracture displacement. Computed tomography imaging is a valuable diagnostic tool for the assessment of ICF.

A guideline for screw fixation of coracoid process base fracture by 3D simulation

BACKGROUND

Fractures of the base of the coracoid process are relatively rare, but an increasing number of studies have reported using screws to fix coracoid process base fractures. This study was performed to simulate the surgical procedure and obtain the ideal diameter, length, insertion point and angle of the screw from a 3-D axial perspective in Chinese patients.

METHODS

We randomly collected right scapula computed tomography (CT) scans from 100 adults. DICOM-formatted CT scan images were imported into Mimics software. A 3D digital model of the right scapula was established. Two virtual cylinders representing two screws were placed from the top of the coracoid process to the neck of the scapula and across the base of the coracoid process to fix the base of the coracoid process. The largest secure diameters and lengths of the virtual screws were measured. The positions of the insertion points and the directions of the screws were also examined.

RESULTS

The screw insertion safe zone can exhibit an irregular fusiform shape according to the reconstructed scapula model. The mean maximum diameters of the medial and lateral screws were 7.08 ± 1.19 mm and 7.34 ± 1.11 mm, respectively. The mean maximum lengths of the medial and lateral screws were 43.11 ± 6.31 mm and 48.16 ± 6.94 mm, respectively. A screw insertion corridor with a diameter of at least 4.5 mm was found in all patients. We found sex-dependent differences in the mean maximum diameters and maximum lengths of the two screws. The positions of the two insertion points were statistically different across sexes.

CONCLUSIONS

The study provides a valuable guideline for determining the largest secure corridor for two screws in fixing a fracture at the base of the coracoid process. For ideal screw placement, we suggest individualised preoperative 3D reconstruction simulations. Further biomechanical studies are needed to verify the function of the screws.

Current challenges and controversies in the management of scapular fractures: a review

Fractures of the scapula are rare and usually associated with high-energy trauma. The unfavorable scapular anatomy, combined with the complexity of the approaches for fracture fixation, make the treatment challenging, even for experienced surgeons. Furthermore, the literature is controversial regarding surgical indications and rationale for treatment. The present review article was designed to address and discuss critical aspects of decision-making for the management of scapular fractures, including surgical indications and patient safety considerations.

Arthroscopic Management of a Coracoid Fracture Associated With Acromioclavicular Dislocation: Technical Note

Operative management of a coracoid process fracture is indicated in case of painful nonunion, displacement of more than 1 cm, or multiple disruptions of the superior shoulder suspensory complex. Several techniques have been described with open reduction of the fracture and internal fixation using cortical screws with or without additional fixation of the acromioclavicular joint. This Technical Note aims to introduce an alternative safe, minimally invasive method for arthroscopic fixation of a coracoid fracture with simultaneously reduction of the acromioclavicular joint. The described arthroscopic technique might be helpful for shoulder surgeons who want to fix the coracoid process while avoiding the disadvantages of an open approach.

Subacute Acromioclavicular Dislocation After Basal Coracoid Process Fracture: Indirect Reduction without Open Reduction and Internal Fixation: A Case Report

CASE

A 55-year-old man presented with an isolated undisplaced basal coracoid process (CP) fracture after direct trauma over his right shoulder. One week later, he presented with pain and anatomical deformity over the acromioclavicular joint (ACJ). Shoulder x-rays and computerized tomography revealed a complete acromioclavicular (AC) dislocation and displaced CP fracture. Anatomical AC reduction and ipsilateral coracoid fracture reduction were obtained using fixation with a hook plate. At 12-month follow-up, the patient regained functionality and showed complete CP consolidation and anatomic alignment of the ACJ.

CONCLUSION

Our alternative treatment of coracoid fracture associated with secondary subacute AC dislocation showed satisfactory functional results.

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.