Echinococcosis is widely distributed in all continents except Antarctica. Western China has a wide distribution of traditional grazing areas and is a high prevalence area for the disease [
3]. According to earlier epidemiological results, 5–30% of the population in western China may be directly threatened by hydatid disease [
4]. Risk factors for the disease include engagement in animal husbandry (livestock raising of sheep, cattle, horses and camels) and contact with domestic or wild canids. In some areas, risk factors also included exposure to contaminated water and food [
5]. The living environment and occupation of the patient in this case were consistent with a typical population susceptible to hydatid disease.According to relevant studies, the most common site of infection for bone hydatid is the spine. The proportion of other skeletal involvement in the total bone hydatid disease varies from study to study. For example, one study mentioned that, in addition to the spine, the femur, tibia, humerus, skull, and ribs were the most frequently involved sites [
6]. Other studies mention the femur, pelvis, humerus, ribs, and tibia as the second most susceptible sites after the spine [
7]. A typical hydatid cyst structure consists of a fibrous adventitia, and an endocyst consisting of a laminar and germinal layer. The most direct evidence of progressive echinococcosis infection is if protoscolex derived from fertile cysts can be found in the suspected cystic lesion [
8]. The initial lesion of an bone hydatid cyst is usually located in the epiphysis and subsequently spreads in the direction of least resistance within the bone tissue. Due to the hardness of the bone, the adventitia is often not formed, but grows infiltrated as a plural daughter cyst [
9]. Clavicle, femur and humerus belong to long bone, which is composed of cancellous bone, wrapped by bone cortex, and has bone marrow cavity. The volume of the bone marrow cavity of the clavicle is relatively large [
10], and the abundant blood supply inside provides nutrition and growth space for echinococci, which may be the reason for the occurrence of this case. Conventional laboratory tests in patients with bone hydatid are usually normal and serological examination is the more specific diagnostic method, but due to the erratic detection rate of the experiment [
11,
12], pathological examination of intraoperative specimens is still widely used in clinical work for the final diagnosis. The typical pathological presentation is a fibrotic adventitia encapsulated by granulomatous tissue or an endocyst in a hyaline folded state, and in less frequent cases the protoscolex can be directly observed [
13]. If the characteristic plural white cystic structures are found intraoperatively, it is highly suspicious of echinococcosis. Although the abnormalities of the bones are very obvious on imaging, the patient does not feel significant discomfort until the local mass appears. Bone hydatid often undergo a long incubation period after infection by the bloodstream route until the onset of symptoms [
14]. When a large cyst appears with a peri-spinal area, the patient could be unconsciously and chronically in an unnatural forced postural change due to abnormal sensation or pulling of the focal tissue, as the imaging suggests to us. Unlike the spinal and pelvic areas where the hydatid are susceptible, cysts located in the long bones rarely cause significant neurological compression [
15]. In addition to mild swelling and pain as early symptoms, many cysts located in the long bones of the extremities are found incidentally with an externally induced pathological fracture as the first diagnostic factor or, as in this case, due to erosion of the bone cortex and extension of the unrestricted cyst into the subcutaneous and surrounding tissues [
16,
17]. Therefore, it is difficult to diagnose and treat long bone hydatid disease in advance [
18]. By the time it is detected, the cyst may have spread widely through the bone marrow cavity and local lesion excision or internal fixation placement often ends in failure [
19,
20]. In order to completely remove the lesion, complete resection of the entire bone, bounded by the joint, is often required [
21,
22]. The clavicle plays a supportive and protective role in the body, but the need for it in upper extremity movement remains controversial [
23,
24]. Lesions involving the clavicle, like malignancies, are sometimes opted for complete removal of the clavicle, and the need for postoperative clavicle reconstruction remains unclear [
25]. In the present case, the patient's ability to perform nonmanual work was not affected, perhaps demonstrating that resection of the clavicle for complete removal of the lesion is worth advocating. The intraoperative specimen shows a uniform enlargement of the clavicle, with rupture of the proximal and distal bone cortices after erosion and outflow of the protoscolex from the medullary cavity, allowing the cyst to spread to the surrounding subcutaneous tissue. In some cases, a period of perioperative chemotherapy prior to surgery has been chosen to reduce the activity of the cysts and to reduce the probability of intraoperative dissemination and recurrence [
26,
27]. However, our cases demonstrate that the rate of local infection spread caused by leakage of broken bone is alarming due to the lax subcutaneous tissue of the neck and anterior chest wall. The clavicle is adjacent to the neck, thorax and mediastinum, and the nearby anatomy is very complex, containing organs, blood vessels and nerves that maintain vital physiological functions, and we believe that immediate treatment of the infected clavicle and cysts within the surrounding tissues is necessary. When performing a hydatid cyst removal procedure, keeping the cyst intact is essential to prevent the spread of the protoscolex. However, when a large hydatid cyst encapsulates bone, we have to incise the adventitia, remove all the endocyst and then remove the affected bone tissue, almost inevitably causing a portion of the endocyst to rupture in the process. Our experience again demonstrates that intraoperative hypertonic saline immersion can effectively inactivate the protoscolex within the occulted cyst and surrounding tissues, avoiding local recurrence of infection. In conclusion, our experience demonstrates that bone hydatid may present in rarer, more dangerous sites and must be managed with prompt and effective surgical management.