Shoulder Surgery for Bone Tumors

Abstract

The proximal humerus is a common location for bone tumors. Those can affect patients of different ages and can be of benign or malignant nature. For bone sarcomas is the 3rd most common location and is a frequent site of spread in non-axial metastatic disease. In pediatric patients is frequent to encounter benign bone tumors in this location but also osteosarcomas and Ewing’s sarcomas. Careful assessment of the patients by a surgeon with the appropriate training is paramount. Shoulder reconstruction for patients with bone tumors encompasses a diverse group of patients, diagnoses and surgical options. While most patients with primary bone tumors may be of a younger age and more involved in sport activities, those with metastatic disease oftentimes are associated with an older age, worse preoperative function and worse prognosis due to the primary disease. The surgeon must weigh in all factors that need to be taken into consideration in the treatment decision-making plan. Currently, with new advances in oncology treatments patients may benefit from longer survivals times than in the past, thus restoring the patient’s function and quality of life is essential.

1. Introduction

The proximal humerus is a common location for bone tumors, benign and malignant, in all age ranges [1, 2, 3]. For bone sarcomas is the 3rd most common location and is a frequent site of spread in non-axial metastatic disease [2]. The most common primary tumors to cause bone secondary lesions are breast, prostate and lung usually through a mechanism of hematogenous spread [4]. In the pediatric population benign tumors outnumber the malignant ones, with osteochondromas and enchondromas being the most frequent [5]. Primary malignant bone tumors are more common at a younger age, with osteosarcoma being the most common followed by Ewing’s sarcoma [6]. While most benign primary bone tumors tend to be asymptomatic and usually diagnosed as an incidental finding, malignant tumors are more likely to cause symptoms. Pain constitutes the main complaint followed by tenderness locally and swelling of the soft tissues. The pain located over the affected bone can be nocturnal, present at rest or constant, of progressive intensity and more or less resistant to over-the-counter pain medication [7]. Malignant and aggressive tumors that remain long periods undiagnosed or without treatment may progress to a pathological fracture, event occurring in up to 10% of osteosarcomas [8]. In the case of metastatic disease, it is an ominous sign and carries a poor prognosis and increased mortality [9].

When patients present initially without a diagnosis the first step is obtaining a thorough history and performing a detailed physical examination, with emphasis on the shoulder function. Following imaging studies need to be obtained. The first imaging exam is a radiograph of the shoulder as well as the humerus (Figure 1). The orthopedic surgeon should assess for the type of lesion; if it is blastic, lytic or mixed; its limits, the presence of periosteal reaction, associated soft tissue masses or a pathological fracture (Figure 2). Computed tomography can also be obtained to assess the cortical integrity of the bone and for surgical planning as well (Figure 3). Additionally computed tomography can show calcifications, healing response in case of pathological fractures and are useful for biopsy guidance as well. The biopsy tract when performed by a physician other than the surgeon should be discussed with the surgeon performing the definitive treatment [10].

Figure 1.

Antero-posterior radiograph of a 17-year-old patient with a destructive lesion of the proximal right humerus with a mixed patter, of lytic lesions and osteoid production, and periosteal reaction.

Figure 2.

Radiographic images, anterior–posterior and lateral of proximal right humerus lytic lesion and pathological fracture in a lung cancer patient.

Figure 3.

Coronal and axial view of a proximal humerus computed tomography without contrast depicting an aggressive-appearing destructive lesion that has eroded through the cortex.

In cases where a primary bone sarcoma is suspected a magnetic resonance should be obtained with and without contrast (Figure 4). The entirety of the bone must be imaged due to the occasional presence of skip lesions [11]. In the case where metastatic disease is suspected or for staging purposes of a primary sarcoma, a bone scan should be obtained to assess for additional bone lesions (Figure 5).

Figure 4.

Magnetic resonance of the humerus with and without gadolinium enhancement. Coronal and axial T1-fat-suppresed with contrast sequence depicting a proximal humerus bone sarcoma with associated surrounding soft tissue component.

Figure 5.

Bone scintigraphy study with Tecnecium-99 depicting a lesion in the proximal left humerus and sternum.

Once a diagnosis has been made the treatment plan needs to be formulated. The goal of surgery will depend on the diagnosis, benign versus malignant, primary versus secondary lesion. In the case of benign lesions surgical treatment is usually reserved for symptomatic patients, for example in the case of an osteochondroma impinging at the extremes of range of motion. For metastatic lesions the goal is to render a pain free and functional patient, taking into consideration the overall prognosis of the disease. For primary bone sarcomas, the mainstay of treatment is surgical resection with adequate margins and a functional reconstruction, preferably performed by a surgeon with experience on sarcoma care [12].

2. Internal fixation for metastatic disease of the proximal Humerus

After assessing the lesion characteristics and the patient’s overall prognosis, a decision has to be made regarding the surgical planning. For widely metastatic disease and a pathological fracture of the proximal metadiaphyseal region internal fixation can be indicated. Intramedullary nailing or a proximal plate and screws are valid options. Both procedures are performed according to the traditional technique and approach. Depending on the location and extent of the lesion, curettage and cement augmentation may be incorporated into the procedure as a means of enhancing disease local control and implant survival. A novel device composed of a liquid photodynamic monomer is an additional alternative providing strength and stability under rotational forces [13]. The advantage of long intramedullary devices in patients with metastatic disease is the protection of the entire bone in the event of further disease progression. Radiotherapy is often indicated postoperatively to increase local disease control [14]. In the event of disease progression, the fixation implant may fail requiring a second, potentially more morbid, surgical procedure for revision (Figure 6).

Figure 6.

Radiograph depicting disease progression of a metastatic lesion in the proximal humerus and bony destruction.

3. Proximal Humerus resection and reconstruction

Primary bone malignancy as well as extensive secondary disease with poor bone stock may require a bone resection followed by reconstruction. In the decision-making process is important to take into account the diagnosis, the patient’s prognosis as well as the structures involved by the tumor which may need to be resected along the bone such as the rotator cuff or the axillary nerve. For proximal humerus tumors the approach is usually the delto-pectoral approach including the biopsy tract, slightly lateral to the delto-pectoral line, with the resection specimen in the case of primary tumors. The surrounding structures involved and included in the resection will determine the postoperative function of the patient and will dictate the type of reconstruction indicated. When both the rotator cuff and an innervated deltoid muscle can be preserved allograph-prostheses composite can be used. If only a functional deltoid is maintained but the rotator cuff is involved in the resection, a reverse total shoulder can be used for the reconstruction. For tumors extending outside of the humerus where the deltoid and rotator cuff have to be resected, a proximal humerus endoprosthesis can be used as a spacer (Figure 7).

Figure 7.

Clinical images and radiographs of a proximal humerus resection. A: Resection piece and trial implant. B: Surrounding soft tissues remaining tagged. C: Implant in place, tagged from the surrounding soft tissues are later attached to the implant. D: Final radiograph showing the implant in place, a long stem was chosen given the presence of metastatic lesions distally.

For proximal humerus tumor resection and reconstruction the complication rate ranges from 20 to 45% [15]. Dislocation of the implant along infection are the most common encountered problems (Figure 8). Besides any hardware or surgically related complications, local recurrences can be another problematic event for these patients. Occurring in 12% of patients, tumor recurrences are a common cause for a subsequent amputation [16]. For surgical constructs where an allograft is added or used as a reconstruction option, the most common complications are fracture, infection and collapse of the subchondral surface [17, 18]. Comparing the diverse options for tumor resection, endoprosthetic replacement is the one associated with lowest complication rates whereas allograft-implant composites would have a better functional outcome [19]. Some authors advocate for the use of a vascular synthetic mesh around the implant for proximal humerus endoprosthetic reconstructions to reduce the rate of dislocations [20, 21]. The mesh creates a surface for adherence of the remaining surrounding soft tissue attachments (Figure 9). For a small percentage of patients, resection and reconstruction may not be an option and an amputation will have to be indicated, fortunately due to advances in surgical implants as well as adjuvant treatments such as radiotherapy and chemotherapy, most patients can benefit from a limb salvage procedure [22]. In cases where the tumor extends into the glenohumeral joint or even into the scapula a Tikhoff-Linberg amputation may be indicated. This procedure consists of an extra-articular resection of all the areas involved by the tumor plus a surrounding adequate surgical margin [23]. This procedure has been associated with high rate of complications and mortality [24, 25].

Figure 8.

Radiographic image depicting a dislocated humeral endoprostheses, one of the most common complications.

Figure 9.

Clinical image of a proximal humerus endoprosthetic replacement with surrounding vascular synthetic mesh and surrounding soft tissues tagged for later reattachment to the mesh.

Prior studies have shown that the implant survivorship for proximal humerus replacement due to primary bone sarcomas is 77% for the first year and 74% at 5 years from the index procedure [26]. Most common reasons for implant failure are infections and local tumor recurrences [26]. The functional outcomes for these patients are going to be determined by the reconstruction type but also by the extent of the resection and the structures involved. The activity level has been shown to decrease significantly in the first year from the initial operation with some improvement after 3 years, yet to lower levels than preoperatively [27]. Moreover, even though most patients remain active and are able to get back and be involved in sport activities, most patients have to switch to a lower extremity activity such as soccer, bicycling or running. Those who prior to surgery practiced sports with overhead activities, unfortunately are usually not able to return to that sport [27]. A slightly improved level of sport performance can be expected in patients where the resection can spare an active deltoid muscle [28]. Some authors also advocate for the use of the synthetic vascular mesh as a means of increasing shoulder function as well [21].

4. Curettage and grafting of benign and aggressive lesions

The proximal humerus is a common location for benign bone tumors such as osteochondromas, enchondromas and unicameral bone cysts. Additionally, it is also a frequent location for more aggressive lesions such as or chondroblastomas. As with other bone tumors the assessment starts with a thorough history taking and physical examination followed by the appropriate imaging studies. In questionable cases or where imaging findings are non-specific a biopsy is indicated, performed ideally by a physician with the appropriate training on bone tumors. For most benign lesions patients are asymptomatic and diagnosis is made incidentally. Non-aggressive lesions such as non-ossifying fibromas, asymptomatic osteochondromas or enchondromas, observation may be all the necessary treatment. Curettage is indicated in the case of aggressive bone tumors that tend to continue to grow causing bone destruction or even a pathological fracture. Others such as atypical cartilaginous tumors may later on dedifferentiate into a higher-grade tumor [29]. The surgery usually involved a small incision over the most direct pathway to the lesion. Once the bone is reached a small window is created with the help of a burr or an osteotome. The lesion is thoroughly and carefully curetted avoiding any spilling of the surrounding tissues. Fluoroscopic visualization may help confirm all the extent of the lesion has been reached (Figure 10). In the case of unicameral bone cysts, intramedullary decompression with the help of a curette or a Kirschner wire of the canal is indicated [30]. In the case of aggressive lesions, the use of adjuvants such as nitrogen, phenol or high-speed burr can help decrease the local recurrence, a common outcome for these type of tumors [31]. Once the lesion has been curetted there are several options for filling such as autologous bone graft, allografts and synthetic bone substitutes (Figure 10).

Figure 10.

Radiographic images depicting a recurrent unicameral bone cyst of the proximal humerus in a pediatric patient and its treatment. A: Unicameral bone cyst of the proximal left humerus. B: Decompression of the canal during the surgical procedure. C: Curettage of the lesion. D: Filling of the cavity with biosynthetic material composed of calcium sulfate with calcium phosphate.

5. Conclusions

Shoulder reconstruction for patients with bone tumors encompasses a diverse group of patients, diagnoses and surgical options. While most patients with primary bone tumors may be younger and more active, those with metastatic disease oftentimes are associated with an older age, worse preoperative function and worse prognosis; all factors that need to be taken into consideration in the treatment decision-making. Currently, with new advances in oncology treatments patients may benefit from longer survivals times than in the past, thus restoring the patient’s function and quality of life is paramount. Ideally, an oncology orthopedic specialist ought to be included in the multidisciplinary treating team from the moment of diagnosis of bone disease.

Conflict of interest

The authors state no conflict of interest related to the writing of this chapter.