Functional Outcomes of Humeral Diaphyseal Hip Spacer in Tumor Resection: A Case Report

Introduction

Reconstructive surgery following the resection of malignant tumors involving the proximal humerus and scapula presents significant challenges, as surgeons seek to preserve optimal limb function and maintain patient quality of life. When resection margins can be achieved, limb-sparing techniques generally provide superior functional and aesthetic outcomes compared to amputation. For sarcomas involving both the scapula and proximal humerus, the complex type IV and VI Tikhoff-Linberg procedures (Figure 1) [1] may be utilized. These procedures involve extra-articular resection of the scapula and proximal humerus and may also require removal of the lateral end of the clavicle.

However, despite the range of available surgical techniques, the reconstruction of extensive periscapular defects remains controversial, with no clear consensus on the optimal approach, especially in cases requiring resection of both the scapula and proximal humerus. Historically, methods such as humeral suspension from the clavicle and the use of prosthetic replacements, including allografts, have been applied. Nevertheless, these techniques are associated with significant limitations, including a high incidence of complications and often unsatisfactory functional outcomes.

This report presents 2 cases that highlight the innovative application of a cemented hip spacer for reconstructive purposes following extensive resection in patients with sarcomas extending from the scapula to the proximal humerus. To our knowledge, the use of a cemented hip spacer in this anatomical context is unprecedented and has not been widely documented in the current literature, emphasizing its novelty. This approach addresses key limitations of traditional reconstruction methods by offering a stable and durable solution with potential functional advantages. The successful outcomes observed in these cases suggest that this technique may serve as a valuable alternative in the context of complex periscapular reconstructions.

Case Reports

SURGICAL TECHNIQUE:

The surgical approach involves a posterior incision to the scapula, extending anteriorly along the humeral border in a sabre-cut manner, incorporating a skin island at the biopsy site (Figure 4). The patient is placed in lateral decubitus position. After identifying the periscapular musculature, the fibers of the upper trapezius are disinserted, followed by the excision of the rotator cuff, deltoid, scapula, and proximal humerus, including the joint capsule, as a single en bloc resection. To facilitate posterior neocapsular reconstruction, part of the acromion is excised with the upper trapezius fibers.

Joint reconstruction is achieved using a cemented humeral diaphyseal hip spacer with dual antibiotic-loaded cement. The new joint capsule is constructed using Trevira mesh, which is fixed to the clavicle and the second costal arch, anchoring the remaining structures (Figure 5).

The surgical durations for the first and second cases were 2 hours 52 minutes and 3 hours 28 minutes, respectively. Following a 24-month follow-up, both patients exhibited favorable clinical outcomes, including disease-free resection margins, no signs of disease progression, 100% survival, and satisfactory aesthetic results with preserved shoulder anatomic shape.

FUNCTIONALITY:

In terms of shoulder function, the first patient had passive shoulder flexion of 90° and active flexion of 20°, along with passive shoulder abduction of 80°, active abduction of 25° and no external rotation. The second patient achieved passive shoulder flexion of 90° and active shoulder flexion of 30°, as well as passive shoulder abduction of 90°, active abduction of 40° and external rotation of 20º. Both patients maintained full function of the elbow, wrist, and hand. The Musculoskeletal Tumor Society (MSTS) scores were 24/36 points for the first case and 19/36 points for the second case, while the Toronto Extremity Salvage Score (TESS) scores were 72/100 and 64/100, respectively.

Discussion

The patients in our case series demonstrated satisfactory upper limb function, shoulder esthetic due to the offset of the hip spacer, and disease-free survival. The second patient exhibited better mobility compared to the first, particularly in terms of external rotation, owing to the anterior tibial tendon allograft, which was sutured to the latissimus dorsi and anchored on the anterior portion of the neocapsule. The decision to employ a tibia allograft in addition to the hip spacer in the second patient was due to the need for more radical surgery because of the tumor size, which necessitated resection of a greater portion of the humerus.

Primary tumors of the upper limb are most commonly found in the proximal humerus and scapula [2]. The resection of aggressive tumors in this region poses a significant challenge for surgeons, as it requires the removal of large portions of the shoulder girdle, including the scapula, proximal humerus, deltoid, and rotator cuff. The primary goal in these cases is to maintain shoulder stability to preserve elbow and hand function. Key factors influencing the structural outcome of such surgeries include whether the resection is intra- or extra-articular, as well as the excision or preservation of the deltoid and trapezius muscles, which affects their suspensory function.

Patients with scapular or periscapular sarcomas may be candidates for the Tikhoff–Linberg procedure [3–5], a surgery involving extra-articular resection of the scapula, proximal humerus, and possibly the lateral end of the clavicle, depending on the classification type. Following tumor excision, a reconstructive technique is required to restore the shoulder girdle.

A variety of reconstructive options exist, including allografts, endoprostheses, and arthrodesis, although there is no clear consensus on the best method. The previous reconstruction methods can be divided into 2 groups, glenohumeral fusion reconstruction methods and glenohumeral nonfusion reconstruction methods. These approaches aim to preserve the affected limb, and with advancements in radiotherapy and chemotherapy, they have become the preferred treatment over amputation, offering superior functional and aesthetic outcomes [6–8].

Several factors must be considered when selecting a reconstructive technique, including the functional outcomes, complication rates, and complexity of the procedure. Most experts agree that shoulder function is compromised in many cases following tumor resection in this region. Broadly, 3 reconstruction options are available after a scapulectomy: humeral suspension, allograft, and scapular prosthesis. Of these, endoprosthetic replacement is likely the most frequently used due to its widespread availability.

Humeral suspension was a popular technique until the 1990s. This method was straightforward and accessible, and was particularly useful in situations where more complex reconstruction options were unavailable. Surgeons employed non-absorbable sutures or pins to stabilize the humeral remnant by attaching it to the clavicle [9–11]. This approach typically required less operative time and a shorter learning curve for surgeons compared to more complex reconstructive techniques. Although limited, this technique provided basic stability to the shoulder region by preventing the complete collapse of the humerus. Despite offering some degree of stability, humeral suspension generally resulted in poor functional outcomes, particularly with respect to active shoulder motion. The lack of a dynamic connection between the humerus and scapula hindered effective movement. Additionally, the absence of contour restoration often led to unsatisfactory cosmetic outcomes, with the shoulder region appearing asymmetrical or indented. The suspension technique did not replicate the biomechanical properties of a fully reconstructed shoulder, resulting in chronic discomfort, difficulty in arm positioning, and long-term dissatisfaction for many patients.

Scapular allografts offer moderate function and stability. When successful, they allow patients to retain some shoulder mobility and strength, especially when at least 1 rotator cuff muscle is preserved. Allografts offer structural continuity in the shoulder girdle, which can aid in restoring a more natural shoulder contour and maintaining the anatomical position of the humerus, thereby supporting a more normal appearance. However, this method carries significant risks, including graft resorption, infection, and fixation failure, which can lead to instability or dislocation of the reconstructed shoulder [12]. While some reports indicate successful functional outcomes, the evidence supporting scapular allografts remains limited, making long-term success rates difficult to predict. This technique necessitates meticulous surgical skill, particularly in securing the allograft to host structures using plates and screws. Furthermore, the success of the procedure may depend on the preservation of at least 1 rotator cuff muscle [13], limiting its applicability in more extensive resections.

Scapular prostheses offer moderate improvement in the shoulder’s active range of motion, potentially enabling better arm elevation, rotation, and limited weight-bearing. As custom-made or modular implants, scapular and humeral prostheses can be designed to accommodate a patient’s unique anatomy, facilitating a more predictable restoration of shoulder structure than allografts. When securely fixed, prostheses provide a stable framework immediately postoperatively, potentially reducing the need for prolonged immobilization and allowing for earlier functional rehabilitation. In contrast, scapular prostheses are associated with complications, with some studies reporting complication rates of up to 20% [7]. Dislocation is a common issue, often due to inadequate soft-tissue support, particularly in patients lacking intact rotator cuff muscles [14]. This reconstruction method is also more susceptible to infections and fixation failures compared to biological reconstructions. Infections can be particularly challenging, often necessitating revision surgery or even removal of the prosthesis. Despite facilitating some motion, scapular prostheses can result in persistent instability due to the inability to restore the complex muscle and ligamentous support of the shoulder girdle, often leading to chronic discomfort and limited functional gains. Reconstruction with 3D-printed scapular prostheses following scapulectomy shows promising functional and clinical outcomes, but further research is needed to validate its long-term efficacy [15–17].

We propose the use of a hip spacer cemented to the remaining humeral diaphysis, combined with a synthetic mesh fixed to the clavicle as a neo-articulation, as an innovative reconstruction technique following scapular sarcoma resection. This approach addresses aesthetic deficits by providing offset and structural stability while preserving upper-limb function, as reported in previous studies by Kyriacou et al [12,14]. The unique shape of the hip spacer offers distinct advantages over shoulder spacers. Specifically, its greater offset facilitates the attachment of the neocapsule to both the second costal arch and the clavicle, establishing 2 points of anchorage, which contributes to improved joint stability and aesthetic appearance. A brachial plexus traction injury can occur in reconstructions where joint stability is not adequately restored, potentially reducing elbow and hand function [6,9,18].

In addition to its anatomical benefits, the hip spacer technique can offer practical advantages such as reduced operative time and lower costs compared to custom prosthetic implants, as it utilizes an off-the-shelf component adaptable to the surgical site. Furthermore, its straightforward design can simplify the surgical procedure and potentially reduce the likelihood of complications associated with more complex, customized reconstructions.

Following the surgery, a structured rehabilitation protocol is essential to optimize functional outcomes. Early mobilization focuses on passive range of motion exercises to maintain flexibility and prevent joint stiffness, followed by progressive strengthening exercises as healing permits. Physical therapy plays a critical role in helping patients regain shoulder stability and function, particularly in compensating for the lost rotator cuff musculature. With a tailored rehabilitation program, patients can achieve meaningful functional improvements, underscoring the clinical relevance of this reconstruction technique.

In an ideal case, Trevira mesh can be secured to the remaining rotator cuff, enhancing shoulder function by increasing stability and active range of motion [19,20]. Trevira mesh is favored over other materials due to its high biocompatibility, which minimizes immune response and promotes integration with surrounding tissues, thus reducing the risk of complications such as infection. Additionally, its flexibility allows it to conform closely to complex anatomical structures, which is particularly beneficial in shoulder reconstructions where maintaining the natural contours is essential for functional recovery. When a sarcoma requires radical excision involving resection of all rotator cuff muscles, as in our cases, Trevira mesh serves as a neo-joint for attaching the remaining structures, supporting residual shoulder function and enabling fixation to both the clavicle and costal arches. This anchoring technique not only helps preserve certain joint functions but also provides structural stability. Furthermore, the use of Trevira mesh facilitates postoperative radiotherapy administration without delay, if needed, due to its compatibility with additional treatments.

The primary challenge following scapular tumor resection is preservation of range of motion. Our functional outcomes (Table 1) were better than in other studies using different reconstruction methods [4,21–23]. The use of an anterior tibial tendon allograft sutured to the latissimus dorsi allowed for some preservation of external rotation in the second patient. However, it is important to acknowledge that there is substantial room for improvement in range of motion in this clinical context.

Conclusions

Malignant tumors in the scapulohumeral region necessitate excision with disease-free margins, often requiring complex reconstructive techniques. The use of a cemented humeral diaphyseal hip spacer for joint reconstruction, secured with Trevira mesh to the clavicle, can restore structural integrity and partial function while addressing the aesthetic deficits caused by the extensive resection. This approach provides offset and contributes to both functional and cosmetic outcomes following aggressive tumor excision. However, larger studies are needed to validate these results.