Radiofrequency ablation of osteoid osteoma at the base of the coracoid process: Report of two cases.

If you encounter an unexplained case of bone marrow edema in a young patient, consider the possibility of osteoid osteoma (OO). Even in the presence of a nidus near vital structures, RFA can safely be used to treat OO.

[Scapular fractures]. / Scapulafrakturen.

Scapular fractures are rare injuries that require different treatment strategies. Nondisplaced fractures and the majority of scapular body fractures can be treated conservatively, while surgical treatment should be considered for displaced fractures involving the glenoid. Displaced glenoid fractures of appropriate size and intra-articular step formation should be treated surgically. Different classification systems for scapular fractures can support the treatment decision. Postoperative and posttraumatic management should include early mobilization to achieve a good functional outcome. Clear recommendations and treatment algorithms at the evidence level are not available and long-term outcomes of scapular fractures are the subject of further investigation. The results published so far show good to excellent results for surgical and conservative treatment, depending on the type of fracture. Individual patient factors should be considered when planning treatment.

Ipsilateral fractures of the acromion and coracoid processes of the scapula.

A fracture of the acromion and coracoid processes of scapula is rarely seen in the outpatient clinic, due to the acromion's anatomical position and shape, as well as the strong ligaments and muscles that are attached to it. These fractures are caused by either direct or indirect high-energy trauma injuries to the shoulder joint, leading to severe pain and a grossly restricted range of motion. Several acromial classifications were reported, but this type of longitudinal plane fracture of the acromion process in our case is yet to be described in the current literature. We present a rare combination of the coracoid process and unstable acromion bony projection fractures that have not previously been noted for this type of fracture. The closest to this is Kuhn's type III classification. A 51-year-old male presented to our emergency department complaining of the right shoulder pain and difficulty raising his arm following a 2-wheeler accident. The patient was managed by open reduction and internal fixation with 3 cannulated cancellous screws fixation and progressed well with no postoperative complications. He was asymptomatic postoperatively and regained full range of motion after 4 months.

A Review of the Typical Course of the Musculocutaneous Nerve into the Coracobrachialis Muscle: Its Variability and Possible Clinical Implications.

OBJECTIVE: This literature review highlights the prevalence of the typical course of the musculocutaneous nerve (MCN) through the coracobrachialis muscle (CB), and evaluates the distance from the entrance point of the MCN to the CB, taking the coracoid process (CP) as a landmark. METHODS: PubMed (MEDLINE), Scopus, and CINAHL online databases were searched in December 2022 for studies reporting the prevalence of the MCN's typical course and the distance between the CP and the MCN entrance point to the CB. RESULTS: Twenty-eight studies were included (including 2846 subjects) investigating the MCN's typical course, and eliciting a prevalence of 93.4%. The mean distance of the CP to the entrance point of the MCN's main trunk into the CB was 5.6±2cm (median 6.1cm, in 550 subjects). In 76.12% of cases the MCN's accessory branches entered the CB proximally to the MCN's main trunk. The mean distance from the CP to the entrance point of the MCN's proximal branches to the CB was 3.8±1.2cm (median 3.7cm, in 140 subjects). CONLCUSION: In the vast majority of cases, the MCN had a typical course through the CB. In cases of altered anatomy, the MCN was either absent or passed medially to the CB (without piercing it). The average entrance point of the MCN into the CB from the CP is 5.6 cm. Proximal motor branches of the MCN to the CB are common and usually arise at a mean distance of 3.8cm from the inferior border of the tip of the CP. Surgeons should be aware of both the MCN's typical and its atypical course and these distances to avoid possible complications when operating in the area.

Anatomical Variations in the Pectoralis Minor Muscle Origin and Insertion: A Systematic Review.

The pathology of the shoulder is among the most widespread medical presentations and may be a result of existing anatomical variations. Therefore, the knowledge of the variations is vital for physicians and clinicians, tasked with treating patients presenting similar complaints to minimize misdiagnosis and prevent iatrogenic injuries. Therefore, the main objective of the present systematic review the variations in pectoralis minor muscle origin and insertion/attachment point. The study also seeks to better inform physicians and clinicians of the task of treating patients with various pathology problems and to ascertain that, upon identification, the pectoralis minor muscle variants are aptly appreciated. The search method used in this systematic review entails the use of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) protocol, and the searching of several online databases, for studies focusing on variations in pectoralis minor muscles. The author reviewer evaluated the studies for eligibility, and the selection criteria for the studies used are described below. This systematic review has disclosed that, in some individuals, the pectoralis minor muscles have their origins in the second, third, and fourth ribs, even as others have their origin in the third and fourth ribs. Still, the systematic review has disclosed that, in certain individuals, the insertion of the pectoralis minor muscle occurs at the supraspinatus tendon, even as there are anomalies in the pectoralis minor insertion points linked to subacromial impingement, possible compression of the brachial plexus anteromedial and the axillary artery, and the subcoracoid impingement.

Recurrent Anterior Shoulder Dislocation After Trauma with Coracoid Apophysis Fracture - A Rare Association.

Anterior dislocations represent about 96% of total shoulder dislocations, with recurrence/instability being more common in young patients. Injury of other shoulder structures is frequent, namely bony Bankart lesion. However, the association with coracoid apophysis fracture is very rare. The present article describes the clinical case of a 67-year-old man who presented to the emergency department with complaints of persistent omalgia, with acute episodes, beginning after a fall from his own height. The patient also presented history of shoulder trauma 3 months earlier, which was evaluated at another hospital. Shoulder anterior dislocation was observed radiographically, and the computed tomography (CT) confirmed bone erosion of the anteroinferior part of the glenoid (bone loss of about 50% of the anteroposterior diameter in the lower region of the glenoid), with almost complete resorption of the bony Bankart lesion (apparent in later analysis of the radiography of the initial traumatic episode). Connectedly, a transverse fracture of the coracoid apophysis (type II in the Ogawa classification) was diagnosed. The patient was submitted to surgical treatment, with anterior bone stop confection using the remnant of the fractured fragment of the coracoid supplemented by tricortical autologous iliac graft, fixed with cannulated screws (according to the Bristow-Latarjet and Eden-Hybinett techniques). In the postoperative follow-up, a good functional result was observed, with no new episodes of dislocation and no significant pain complaints. A rare association of shoulder lesions is described, and the challenge of their treatment is highlighted, given the late diagnosis, as in the case presented.

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.

Recurrent Anterior Shoulder Dislocation After Trauma with Coracoid Apophysis Fracture - A Rare Association / Luxação anterior recorrente do ombro após traumatismo com fratura apófise coracoide - Uma associação rara

Abstract Anterior dislocations represent about 96% of total shoulder dislocations, with recurrence/instability being more common in young patients. Injury of other shoulder structures is frequent, namely bony Bankart lesion. However, the association with coracoid apophysis fracture is very rare. The present article describes the clinical case of a 67-year-old man who presented to the emergency department with complaints of persistent omalgia, with acute episodes, beginning after a fall from his own height. The patient also presented history of shoulder trauma 3 months earlier, which was evaluated at another hospital. Shoulder anterior dislocation was observed radiographically, and the computed tomography (CT) confirmed bone erosion of the anteroinferior part of the glenoid (bone loss of about 50% of the anteroposterior diameter in the lower region of the glenoid), with almost complete resorption of the bony Bankart lesion (apparent in later analysis of the radiography of the initial traumatic episode). Connectedly, a transverse fracture of the coracoid apophysis (type II in the Ogawa classification) was diagnosed. The patient was submitted to surgical treatment, with anterior bone stop confection using the remnant of the fractured fragment of the coracoid supplemented by tricortical autologous iliac graft, fixed with cannulated screws (according to the Bristow-Latarjet and Eden-Hybinett techniques). In the postoperative follow-up, a good functional result was observed, with no new episodes of dislocation and no significant pain complaints. A rare association of shoulder lesions is described, and the challenge of their treatment is highlighted, given the late diagnosis, as in the case presented.

Resumo As luxações anteriores representam cerca de 96% do total de luxações do ombro, sendo a recidiva/instabilidade mais comum em pacientes jovens. A lesão de outras estruturas do ombro é frequente, nomeadamente a lesão óssea de Bankart. Contudo, a associação com a fratura da apófise coracoide é muito rara. Este artigo descreve o caso clínico de um homem de 67 anos que recorreu ao serviço de urgência com queixas de omalgia persistente, com episódios de agudização, iniciados após queda da própria altura. O paciente apresentava ainda histórico de trauma do ombro 3 meses antes, avaliado em outro hospital. A luxação anterior do ombro foi constatada radiograficamente, e a tomografia computorizada (TC) do ombro confirmou erosão óssea da vertente anteroinferior da glenoide (perda óssea de cerca de 50% do diâmetro anteroposterior na região inferior da glenoide), com reabsorção quase completa de lesão óssea de Bankart (aparente em análise a posteriori da radiografia do episódio traumático inicial). Associadamente, foi diagnosticada uma fratura transversa da apófise coracoide (tipo II da classificação de Ogawa). O paciente foi submetido ao tratamento cirúrgico, com confecção do batente ósseo anterior utilizando remanescente do fragmento fraturado do coracoide suplementado por enxerto autólogo tricortical do ilíaco, fixados com parafusos canulados (de acordo com as técnicas de Bristow-Latarjet e Eden-Hybinett). No seguimento pós-operatório, foi observado um bom resultado funcional, sem novos episódios de luxação e sem queixas álgicas significativas. Descreve-se uma associação rara de lesões do ombro, e salienta-se o desafio do tratamento das mesmas dado o seu diagnóstico tardio, como no caso apresentado.

A Unique Presentation of the Glenoid, Coracoid, and Proximal Humerus Fractures.

Fractures of the proximal humerus are common injuries with a bimodal age distribution. They usually present in younger patients after high-energy trauma and in elderly patients after lower-energy trauma. Fractures of the proximal humerus are rarely associated with concomitant fractures of the glenoid, and this is a complex injury pattern that indicates the presence of significant instability. Such injuries are usually treated surgically. Even more rarely, patients may present with proximal humerus fractures and fractures of the coracoid process. A male patient presented to our emergency department (ED) after a fall off the loading platform of his heavy goods vehicle (HGV), resulting in a right shoulder injury. During his initial assessment in ED, a computerised tomography (CT) scan demonstrated the presence of a comminuted proximal humerus fracture, a comminuted anterior glenoid wall fracture, and a coracoid process displaced fracture. Surgical fixation of all three fractures was undertaken in the same sitting. This is the first case described in the literature with a combination of the above injuries and serves as a reminder that as trauma complexity and incidence continue to increase, we should maintain a high index of diagnostic suspicion when dealing with such patients. Furthermore, we present our treatment approach for this case and the rationale behind it.

Treatment of acromioclavicular dislocations with a concomitant coracoid fracture: a systematic review of 37 patients.

Background: Acromioclavicular (AC) dislocations with a concomitant fracture of the coracoid process (CP) are rare and there is ambiguity on treatment options. This systematic review was performed to address the clinically relevant question: what are the shoulder functions, union rates, and expected time until return to daily life in patients with a dislocation of the AC joint with a concomitant CP fracture after (1) nonsurgical treatment, (2) sole fixation of the AC joint, and (3) fixation of both the AC joint and the coracoid process? Methods: Studies were identified by conducting an online. Thirty records met the inclusion criteria and were suitable for data extraction. Results: A total of 37 shoulders from 37 patients were included. Surgical treatment was provided to 22 out of 37 patients, and 15 patients had nonsurgical treatment. Out of the surgically treated patients, 12 patients were treated with a fixation of both the AC joint and the CP, 9 patients with a sole fixation of the AC joint, and 1 patient with a sole fixation of the CP. Conclusion: Existing literature does not indicate that one treatment option is superior, and more data are needed to guide evidence-based decisions on this rare injury.

Coracoid process transfer and distal clavicle resection for chronic acromioclavicular separation.

Background: Dewar's procedure for transferring the coracoid process with the short head of biceps and coracobrachialis was reported in 1965 for treatment of both acute and chronic acromioclavicular (AC) joint separation, but little contemporary literature exists around the procedure. We report the clinical results of coracoid process transfer with excision of the lateral end of the clavicle for chronic AC joint separation. Methods: Fifty-one patients (39 men and 12 women, mean age 46 ± 16 years) were included in the study. Clinical outcomes were evaluated using the American Shoulder and Elbow Surgeons and the Japanese Orthopaedic Association scores, as well as by measuring active range of motion in the shoulder, before-after (minimum follow-up time of 24 months [27 ± 3 months]) surgery. Plain radiographs were used to examine stability of the AC joint and bone union of the graft. Results: The mean American Shoulder and Elbow Surgeons and Japanese Orthopaedic Association scores increased (from 61 ± 14 to 91 ± 6, and from 54 ± 9 to 89 ± 8, respectively) at the time of final follow-up. There were no differences in active elevation and external rotation between before-after operation. Six patients whose grafts were fractured or displaced showed complete or partial loss of reduction of the AC joint. Conclusion: By transferring the coracoid process, the AC joint regained stability after chronic joint separation. Although potential complications related to the graft still need to be addressed, Dewar's procedure and lateral clavicle resection could be a reliable treatment of chronic AC joint separation.

Proportional localisation of the entry point of the coracobrachialis muscle by the musculocutaneous nerve along the humerus.

PURPOSE: To project the distance between the tip of the greater tubercle (GT), respectively, the proximal border of the tip of the coracoid process (CP) and the entry point of the coracobrachialis by the musculocutaneous nerve (MCN) proportionally onto the humeral length. METHODS: Sixty-six upper extremities were included in the study. The distance between the tip of the GT and the distal tip of the lateral humeral epicondyle (LE) was evaluated as the humeral length (HL). The interval between the tip of the GT and the entry point of the coracobrachialis muscle by the MCN was measured. The distance between the proximal border of the tip of the CP and the distal portion of the medial humeral epicondyle (ME) and the entry point of the MCN into the coracobrachialis were evaluated. Proportions were used to project the entry point of the coracobrachialis by the MCN along the HL, respectively, the interval between the proximal border of the tip of the CP and the distal tip of the ME. RESULTS: The entry point of the MCN into the coracobrachialis muscle can be expected at an interval between 14.9 and 33.9% of the HL (between the tip of the GT and the LE), starting from the tip of the GT. Regarding the reference line between the proximal border of the CP and the ME, the nerve's entry point was located between 14.2 and 34.4%, starting from the CP. CONCLUSION: Results represent easily applicable intervals for intraoperative localisation of the MCN.

Morphological classification and clinical significance of the coracoid process based on CT three-dimensional reconstruction / 解剖学报

Objective To provide anatomical basis for clinical treatment of acromioclavicular joint dislocation by studying the morphology of coracoid process of human scapula. Methods A total of 500 patients with shoulder injury were selected from the Affiliated Hospital of Traditional Chinese Medicine of Southwest Medical University in Sichuan Province, and 300 patients were selected as subjects, including 159 cases of right shoulder and 141 cases of left shoulder. CT scan images and 3D reconstruction results of scapula of the subjects were collected. The basic morphological characteristics of coracoid process CT images of the subjects were observed, and the relevant parameters were measured, including the longest horizontal distance of the coracoid process tip and the thickness of the midpoint (cd, pp’), the distance from the upper part of the coracoid process scapula to the base and the thickness of the midpoint (mn, kk’). The distance from the apex of the coracoid process to the base of the coracoid process (ab), the longest horizontal distance of the recursion part of the coracoid process (ef), the distance of as (point s was the intersection of point a perpendicular to mn), the distance of hj (point h and j were the intersection of the base of the coracoid process and the recursion part respectively), and ik (point i was the intersection of point k perpendicular to mn and the coracoid process retraction). Results According to the morphological characteristics of coracoid process, they were divided into five types, including peanut 29. 7%; Short rod type accounted for 27. 4%; Melon seed type accounted for 12. 6%; Rod type accounted for 17. 0%; Wedge type accounted for 13. 3%. Through data comparison, it was found that the distance ef and distance hj on the left were larger than those on the right, P<0. 05. All types had statistical difference in comparison distance cd, P<0. 05. The melon seed type showed statistical differences with peanut type, wedge type, long stick type and short stick type in thickness pp’, distance ab and as of point p, P<0. 05. In the comparison of point K thickness kk’, there was statistical difference between melon seed type and other four types, P<0. 05. In the distance ab comparison, there was statistical difference between the short bar type and the other four types, P < 0. 05. Conclusion The study on the morphology of coracoid process can provide anatomical basis for clinical reconstruction of coracoid ligament to treat acromioclavicular joint dislocation.

Técnica modificada de Boytchev para luxación recidivante de hombro

Introducción: La luxación anterior del hombro es una lesión ortopédica con alto riesgo de desarrollar inestabilidad glenohumeral anterior. Su tratamiento es quirúrgico y existen varias técnicas que permiten la reconstrucción. Objetivo: Mostrar los resultados de la técnica modificada de Boytchev para el tratamiento de la inestabilidad anterior de hombro. Métodos: Estudio retrospectivo, tipo serie de casos, con pacientes operados con técnica modificada de Boytchev. Con ella se redirecciona el tendón conjunto del bíceps y se pasa por detrás del músculo subescapular para mejorar el soporte en la cara anterior de la articulación glenohumeral. Resultados: Se operaron 22 pacientes que tuvieron un seguimiento mínimo de 43 meses. Todos pudieron retornar a sus actividades laborales y deportivas. Ninguno presentó recidiva y la movilidad fue completa. En un caso el material de osteosíntesis se aflojó, pero se solucionó sin complicaciones. Conclusiones: Se trata de una técnica quirúrgica que permite restituir la tensión de los tejidos blandos anteriores del hombro y corregir de forma satisfactoria su inestabilidad; no expone la cápsula articular ni altera la longitud del tendón conjunto, lo que deriva en menor fibrosis. Es reproducible y segura, con baja tasa de complicaciones y permite el retorno a las actividades físicas sin comprometer la movilidad del hombro.

Introduction: Anterior shoulder dislocation is an orthopedic injury with high risk of developing anterior glenohumeral instability. Its treatment is surgical and there are several techniques allowing reconstruction. Objective: To display the results of the modified Boytchev technique for the treatment of anterior shoulder instability. Methods: This is a retrospective study, case series type, with patients operated with modified Boytchev's technique. It redirects the conjoined biceps tendon and it is passed behind the subscapularis muscle to improve support on the anterior aspect of the glenohumeral joint. Results: Twenty two patients who had a minimum follow-up of 43 months were operated on. All were able to return to their work and sports activities. None had recurrence, mobility was complete. In one case, the osteosynthesis material loosened, but it was fixed without complications. Conclusions: This is a surgical technique that allows restoring the tension of the anterior soft tissues of the shoulder and satisfactorily correcting its instability; it does not expose the joint capsule or alter the length of the joint tendon, which results in less fibrosis. It is repeatable and safe, with a low rate of complications and allows returning to physical activities without compromising shoulder mobility.

Osteoid Osteoma of the Coracoid Process Presenting as Adhesive Capsulitis in a 10-Year-Old Male: A Case Report.

A 10-year-old male presented with symptoms in his right shoulder indicative of adhesive capsulitis. Radiographic films did not demonstrate any osseous abnormalities. Magnetic resonance imaging demonstrated the presence of an eccentric lesion within the coracoid process consistent with an osteoid osteoma. Six months after surgical removal the patient is back to full activities. For the pediatric population, surgeons must always consider diagnoses that could alter a patient's growth or result in long-term disability. In particular, an atypical presentation of musculoskeletal disease in a pediatric patient presenting with a disease that typically is seen in the older population warrants further workup.

A lower critical coracoid process angle is associated with type-B osteoarthritis: a radiological study of normal and diseased shoulders.

Background: Degenerative rotator cuff tears and osteoarthritis (OA) are associated with differences in coronal plane scapular morphology, with particular focus on the effect of the critical shoulder angle (CSA) on shoulder biomechanics. The effect, if any, of axial plane scapular morphology is less well established. We have noticed wide disparity of axial coracoid tip position in relation to the face of the glenoid and sought to investigate the significance of this through measurement of the critical coracoid process angle (CCPA), which incorporates coracoid tip position and glenoid version. Methods: CCPA, CSA, and glenoid retroversion were measured by three independent reviewers from the cross-sectional two-dimensional computed tomography (CT) and magnetic resonance imaging of 160 patients in four equal and matched case-control groups: (1) a control group of patients with a radiologically normal shoulder and no history of shoulder symptoms who had a CT thorax for another reason, (2) patients with primary OA with Walch type-A glenoid wear pattern on CT scan, (3) patients with type-B glenoid primary OA, and (4) patients with magnetic resonance imaging-proven atraumatic tears of the posterosuperior rotator cuff. Results: Interobserver agreement was excellent for all measured parameters. The median CCPA was significantly lower in the type-B OA group (9.3˚) than that in controls (18.7˚), but not significantly different in the other study groups. There was a trend toward greater glenoid retroversion in the type-B OA group, but receiver operating characteristic curve analysis demonstrated the CCPA to be by far the most powerful discriminator for type-B OA. The optimal cutoff value was calculated for the CCPA at 14.3˚ with a sensitivity of 93% and specificity of 90% for type-B OA. Compared with controls, the CSA was significantly higher in the rotator cuff tear group and lower in both OA groups, but did not differentiate between type-A and type-B OA. Conclusion: Combined with a lower CSA, a lower CCPA (<14.3˚) is strongly predictive of type-B glenoid OA. The authors propose a simple model of pectoralis major biomechanics to explain the effect of this axial plane anatomical variation, which requires further investigation.

Morphology of the coracoid process as a predictor of articular-side tear at the upper border of the subscapularis.

BACKGROUND: Articular-side tear at the upper border of the subscapularis (SSC-AST) is often detected during shoulder arthroscopic surgery, although its exact pathology remains unknown. The purpose of this study was to investigate the correlation between various characteristics of the coracoid process, including classification of the morphology of the coracoid process tip, and the presence of SSC-AST. METHODS: This retrospective, case-controlled study included patients who underwent arthroscopic subacromial decompression with or without rotator cuff repair between January 2018 and September 2021. A total of 130 shoulders in 124 patients, including 77 male and 53 female shoulders (mean age at surgery, 64 years [range, 39-88 years]), were included in this study. Three-dimensional (3D) computed tomography examination was performed preoperatively, and the following indices were measured: coracoid proximal length, coracoid distal length, coracoid angle, coracoglenoid angle, offset of the coracoid process and glenoid (anterior, lateral, and superior offset), and coracoid base angle. The morphology of the tip of the coracoid process was classified into 3 types according to 3D reconstructed views: flat type, round type, and beak type. The presence of SSC-AST was intraoperatively evaluated arthroscopically via a posterior glenohumeral portal. Morphologic risk factors for SSC-AST were evaluated between SSC-AST cases (group T) and non-SSC-AST cases (group N) by multivariable logistic analysis. In addition, the correlation between the incidence of SSC-AST and classification of the tip of the coracoid process was analyzed. RESULTS: SSC-AST was present in 53 shoulders (40.8%). Group T patients were significantly older than group N patients (68.4 ± 10.0 years vs. 61.5 ± 11.8 years, P < .001). No sex difference was detected between the 2 groups (28 male and 25 female shoulders in group T vs. 49 male and 28 female shoulders in group N, P = .28). Multivariate analysis of morphologic parameters between the 2 groups detected a smaller superior offset as a risk factor for SSC-AST (odds ratio, 0.91; 95% confidence interval, 0.84-0.98; P = .01). No significant differences were found in the other parameters. Regarding classification of the tip of the coracoid process, round- and beak-type coracoid tips had a significantly higher rate of SSC-AST than flat-type tips (flat type, 21.8%; round type, 64.7%; and beak type, 46.3%) (P < .001). CONCLUSIONS: Evaluation of the correlation between the morphology of the coracoid process on 3D computed tomography and the presence of SSC-AST visualized during arthroscopy indicated a significant association between SSC-AST and the morphology of the coracoid process.

Classification and morphological parameters of the coracoid process in Chinese population.

INTRODUCTION: The coracoid process is an important anatomical structure of the scapula, which can be used as a landmark in the diagnosis and treatment of scapula related diseases, such as acromioclavicular joint dislocation, anterior shoulder instability, and coracoid fractures. The aim of this study was to classify the coracoid process according to morphology and to measure the morphological parameters of the coracoid process. MATERIALS AND METHODS: A total of 377 dry and intact scapulae were collected and classified in terms of the connection between the shape of coracoid process and common things in life. The anatomical morphology and the position related to acromion and glenoid socket of the coracoid process were measured in each type by three independent researchers with a digital caliper. The measurements were averaged and recorded. RESULTS: Based on obvious morphological features, five specific types of the coracoid process were described: Type I, Vertical 8-shape; Type II, Long stick shape; Type III, Short stick shape; Type IV, Water drop shape, and Type V, Wedge shape. Type I (30%) and Type III (29%) were more prevalent in China. The tip width of the coracoid process of Type IV was the shortest and significantly different compared to the other types (p <.05), contrary to the longest in Type V. The tip thickness of the coracoid process of Type I was the shortest and significantly different from the other types (p <.05). CONCLUSIONS: The coracoid process was classified into five types based on obvious morphological features. Knowing of morphological classification and anatomical parameters of different types of the coracoid process, to some extent, may be helpful to diagnose and treat the shoulder joint disease, such as acromioclavicular joint dislocation, anterior shoulder instability, and coracoid fractures, and to theoretically reduce postoperative complications.

A biomechanical comparison of steel screws versus PLLA and magnesium screws for the Latarjet procedure.

INTRODUCTION: The fixation of the coracoid process onto the glenoid is an important step of the Latarjet procedure, and implant-associated complications are a relevant and severe problem. This study compares the fixation strength and failure mode of two biodegradable materials with stainless-steel screws. METHODS: 24 Fresh-frozen cadaveric scapulae were divided into three groups of equal size and received a coracoid transfer. Cadavers were matched according to their bone mineral density (BMD). In group 1, small-fragment screws made of stainless steel were used. In the second group, magnesium screws were used, and in the third group, screws consisted of polylactic acid (PLLA). A continuously increasing sinusoidal cyclic compression force was applied until failure occurred, which was defined as graft displacement relative to its initial position of more than 5 mm. RESULTS: At 5-mm displacement, the axial force values showed a mean of 374 ± 92 N (range 219-479 N) in group 1 (steel). The force values in group 2 (magnesium) had a mean of 299 ± 57 N (range 190-357 N). In group 3 (PLLA), failure occurred at 231 ± 83 N (range 109-355 N). The difference between group 1 (steel) and group 2 (magnesium) was not statistically significant (P = 0.212), while the difference between group 1 (steel) and group 3 (PLLA) was significant (P = 0.005). CONCLUSION: Stainless-Steel screws showed the highest stability. However, all three screw types showed axial force values of more than 200 N. Stainless steel screws and PLLA screws showed screw cut-out as the most common failure mode, while magnesium screws showed screw breakage in the majority of cases. EVIDENCE: Controlled laboratory study.