Anatomical study for the treatment of proximal humeral fracture through the medial approach.

BACKGROUND: The treatment of complex 3- and 4-part proximal humeral fractures has been controversial due to numerous postoperative complications. With the further study of medial support and blood supply of humeral head, new techniques and conception are developing. The study aims to illustrate the medial approach of the proximal humeral fracture through cadaver autopsy. METHOD: Upper limbs from 19 cadavers have been dissected to expose the shoulder joint. We selected the coracoid process as the bony reference. Vernier caliper will be used to measure the following data, including distance from coracoid process to circumflex brachial artery, distance between anterior humeral circumflex artery (ACHA) and posterior circumflex brachial artery (PCHA) and their diameters. Assessment included the characteristics of the vascular supply around the humeral head, identification of the structures at risk, quality of exposure of the bony structures, and feasibility of fixation. RESULTS: The medial approach is appropriate in 86.84% anatomical patterns. Between the lower part of the shoulder capsule and the insertion of conjoined tendon, the bony surface exposed was limited by the interval between ACHA and PCHA. An interval of 2 to 3 cm (24.29 ± 3.42 mm) was available for medial plate. ACHA (49.35 ± 8.13 mm, 35.14-68.53 mm) and PCHA (49.62 ± 7.82 mm, 37.67-66.76 mm) were about 5 cm away from the coracoid process. Risk structures including ACHA and PCHA originate in common, PCHA originated from the deep brachial artery (DBA), the presence of perforator vessels, musculocutaneous nerve intersects with ACHA, the diameter of PCHA: ACHA < 1.5. In 13.15% anatomical patterns, this risk structure should be taken seriously. CONCLUSION: The medial approach opens a new perspective in the optimal management of complex fractures of proximal humerus. Anatomical research proves that the medial approach is feasible. The interval between ACHA and PCHA is suitable for placement. Anatomical pattern and indication have been discussed, and we hypothesized that ACHA has been destroyed in complex PHFs. With further studies on the anatomy and mechanism of injury, the development of more clinical cases will be an important work of our institution in the future.

Reproducibility of the modified Neer classification defining displacement with respect to the humeral head fragment for proximal humeral fractures.

BACKGROUND: Although the Neer classification is widely used for the assessment of proximal humeral fractures, its reproducibility has been challenged. The purpose of this study was to evaluate the reproducibility of the conventional Neer classification and a modified classification that defined fracture displacement with respect to the humeral head fragment. METHODS: The fracture patterns in 80 cases of proximal humeral fractures were independently assessed by 6 observers. The cases were grouped according to the conventional Neer classification using radiographs followed by computed tomography (CT) scans by each examiner twice with a 1-month interval. The fractures were then classified with the modified Neer classification, which defined displacement of the fragment as separation of more than 1 cm or angulation of more than 45° from the humeral head fragment, twice with a 1-month interval. Kappa coefficients of the conventional and modified Neer classifications were compared. RESULTS: The modified classification showed significantly higher intra-observer agreement than the conventional classification, both for radiographs (P = .028) and for CT scans (P = .043). Intra-observer agreement was also significantly higher for the modified classification than for the conventional classification, both for radiographs (P = .001) and for CT scans (P < .001). CONCLUSIONS: The present study showed that agreement for the Neer classification could be improved when fracture displacement was defined as separation or angulation from the humeral head. Considering vascularity to the humeral head, furthermore, the modified method might be more helpful for predicting patients' prognosis than the conventional Neer classification.

A Detailed Analysis of the Blood Supply to the Subscapularis Muscle.

This study aimed to provide a comprehensive description of the arterial supply to the subscapularis (SSC) muscle. This will provide critical information for various surgical procedures. Ten specimens of embalmed Korean cadavers were dissected and subjected to modified Sihler's method to reveal the branching pattern of the arteries surrounding the subscapularis, and its intramuscular blood supply. The SSC muscle was generally supplied by branches from the subclavian artery (suprascapular artery, supraSA; circumflex scapular artery, CxSA; and dorsal scapular artery, dSA) and the axillary artery (subscapular artery, subSA; lateral thoracic artery, LTA; posterior circumflex humeral artery, PCxHA; and a branch of the axillary artery, AAbr). The anterior aspect of the muscle was supplied by the subSA, LTA, CxSA, supraSA, and AAbr. The posterior aspect of the muscle was supplied by the supraSA, PCxHA, and subSA. The dSA was more scarcely distributed than the other arteries. In two cases, the dSA supplied the portion of the muscle near the medial border of the scapular. The anterior side of the muscle tendon was supplied by the CxSA, and its posterior side was supplied by the PCxHA. The subSA can be considered to be the main branch supplying the SSA based on its distribution area of arteries. It was mostly situated within the lower region of the SSC. After distributing to the anterior surface of the SSC, some branches of the subSA reached the posterior surface as perforating branches. Clin. Anat. 32:642-647, 2019. © 2019 Wiley Periodicals, Inc.

Analysis of four-fragment fractures of the proximal humerus: the interest of 2D and 3D imagery and inter- and intra-observer reproducibility.

The treatment of the four-part fractures of the proximal humerus remains a therapeutic challenge. The decision-making is based on preoperative criteria concerning the displacement of the fracture, the stability of the fracture and the risk of avascular necrosis of the humeral head. The aim of this study was to analyse the inter- and intra-observer reproducibility of those criteria previously described by Hertel. Three observers analysed three times 20 radiologic files comprising 2D X-rays, 2D CT scan and 3D reconstructions for the intra-observer study, and an expert committee was used to assess the inter-observer reproducibility. The Kappa coefficient was used to measure agreement. The Kappa coefficient founded poor to moderate agreement for the majority of the criteria after the 2D X-ray analysis. This coefficient was improved with the use of 2D CT scan and 3D reconstructions, in particular for the medial hinge assessment, the humeral head fracture and the metaphyseal extension. The reproducibility of the criteria described by Hertel on 2D X-rays is at least moderate. Reproducibility could be considerably improved by associating 2D scans and 3D reconstruction, in particular for the criteria related to prognosis for the vascularisation of the humeral head.

Excision and Reimplantation of the Proximal Humerus After Fracture-Dislocation.

Fractures of the proximal humerus are common and the treatment for both displaced and comminuted variants remains controversial. Treatment options initially consisted of closed reduction, traction, casting, and abduction splints. In the early 1930s, operative treatment for displaced fractures gained popularity, which continued in the 1940s and 1950s. Humeral head replacement for severely displaced fractures of the proximal humerus was introduced in the 1950s. In the 1970s, the Association for Osteosynthesis/Association for the Study of Internal Fixation popularized plates and screws for fracture fixation, and humeral head prostheses were redesigned. The traditional management of severely displaced proximal humerus fractures has been with arthroplasty because of the significant risk of osteonecrosis of the humeral head following open reduction and internal fixation. The authors present a case of a 51-year-old right-hand-dominant man who sustained a seizure along with a posteriorly displaced proximal humerus fracture-dislocation of the right upper extremity. This was treated with surgical extrusion of the entire humeral head and subsequent open reduction and internal fixation. During the surgical procedure, the patient's humeral head was completely extruded from the body through a posterior incision and then reduced back to the proximal humerus through the standard anterior deltopectoral approach. After 4 years of follow-up, the patient remains pain free, has functional range of motion, and is without signs of osteonecrosis on plain radiographs. This case illustrates that even with complete disruption of the vascular supply to the humeral head, revascularization after osteosynthesis is possible. [Orthopedics. 2016; 39(4):e779-e782.].

Rapid collapse of the humeral head after arthroscopic rotator cuff repair.

UNLABELLED: This report presents a case of rapidly progressive collapse of the humeral head following arthroscopic rotator cuff repair. We performed humeral head replacement 8 months after the index surgery; histological examination of the collapsed area revealed necrosis, degeneration, fibrillation, and granulation in the cartilage and trabeculae. Osteonecrosis due to the use of metal anchors was considered the primary cause of the post-operative humeral head collapse. As the demand for arthroscopic cuff repair is expected to increase in the future, we recommend that surgeons become aware of the potential for complications, as seen in the present case. LEVEL OF EVIDENCE: IV.