Trapezius Muscle Flap for Posterior Neck and Shoulder Defects Following Malignant Tumor Resection—A Case Series from a Tertiary Cancer Facility

Abstract

Reconstructing defects of the shoulder and posterior scalp, arising following tumor resection, requires careful consideration of available options. While free tissue transfers and local advancement flaps have their established roles, the trapezius muscle flap offers a unique set of advantages like proximity, versatility, and reliability as it has a robust blood supply and relatively straightforward surgical technique. In this retrospective analysis, demographic and disease profiles of 10 patients with posterior scalp and shoulder defects following tumor resection, which were reconstructed with a trapezius flap between November 2020 and November 2023, were studied. Complications and functional outcomes were analyzed. Ten patients (9 men and 1 woman) were reconstructed using a trapezius flap. The mean age of the study sample was 45.3 years (30–60 years). Two patients developed donor site seroma and one of them developed wound dehiscence; one patient had partial necrosis of the flap tip, all managed conservatively, and one patient had tumor recurrence. However, the long-term result was good in all patients except the one with recurrence. The post-excision defects in the shoulder and posterior scalp were of mean size 13 ± 2 × 6 ± 2 cm, and the donor site morbidity analyzed by using VAS (visual analog scale) had a mean score of less than 3. This case series provides valuable insights into the successful use of the trapezius muscle flap for shoulder and posterior scalp defects following malignant tumor resection. The documented complications are minimal in comparison to the overall positive outcomes, making the trapezius muscle flap a viable and reliable option for reconstruction in this specific clinical scenario. However, further research is required to improve the design of the flap for different types of defects, refine surgical techniques, and compare outcomes with other reconstruction methods.

Introduction

Reconstruction of defects created after the excision of the shoulder and posterior neck can be an extremely challenging task. There are many reconstruction options like free flaps and local flaps, but trapezius flap utility in literature for such defects is much less documented. The trapezius flap, which was described by Nakajima and Fujino in 1984 [1], was originally conceptualized as a myocutaneous or muscle flap and has since been utilized as a skin flap and free flap. Its application in head and neck reconstruction, particularly in salvage procedures has been documented.

Despite the trapezius flap’s efficacy, it is not commonly employed for posterior neck and occipital scalp reconstruction, as the abundance of neck and temporal vessels often favors the use of free flaps [2]. However, in elderly patients where prolonged operation times associated with free flaps are less suitable also in centers with less availability of plastic surgeons, the trapezius flap emerges as a viable alternative due to its shorter operation time and minimal functional deficits. Also, the robust vascular supply of the trapezius muscle flap can reduce infection risks.

One major factor limiting the widespread use of the trapezius muscle flap is the lack of familiarity with its surgical anatomy. According to the Mathes and Nahai classification [3], the trapezius muscle exhibits a type II vascular pattern [4] with dominant and minor vascular pedicles, primarily derived from the transverse cervical artery (TCA). It has both the deep branch of the TCA and the dorsal scapular artery (DSA) as the dominant blood supply, but whether one is predominant is still a matter of debate. However, there are many variations according to the population and also the geography of the study patients.

This case series aims to delineate the clinical application of the trapezius flap in posterior neck and shoulder reconstruction, along with an analysis of the technique, complications with its management, and technical difficulties faced during the study period. Ten cases in 3 years emphasize the fact of how rare the use of trapezius flap is, even in a high-volume tertiary care center.

Materials and Methods

After obtaining approval from the institutional ethics committee, a retrospective review was done of the cases for which a trapezius flap was utilized to reconstruct shoulder and posterior neck defects. The review was conducted in the Department of Surgical Oncology between November 2020 and November 2023.

Inclusion Criteria

1. Patients diagnosed with malignant tumors necessitating surgical resection leading to shoulder and posterior neck defects.

2. Individuals for whom the trapezius flap was the chosen reconstructive option post-tumor resection.

3. Availability of comprehensive medical records: Cases with detailed preoperative assessments, intraoperative notes, and comprehensive post-operative follow-up records to ensure thorough data collection and analysis.

Exclusion Criteria

1. Cases where reconstructive surgery involved techniques other than the trapezius muscle flap.

2. Incomplete medical records: Patients lacking comprehensive preoperative assessments, intraoperative details, or adequate post-operative follow-up records essential for thorough data collection and analysis.

3. Patients who did not give consent were excluded from the study.

The study utilized patient discharge cards, follow-up records, and data analysis to examine patient profiles and disease characteristics. All patients were categorized based on the AJCC/TNM 2018 classification for their respective types of tumors using clinical and radiological methods such as CECT and CE MRI. Following institutional protocols, patients were monitored for a minimum of 1 year after surgery. The study assessed the flap’s condition, complications of the procedure, and functional outcomes.

Results

Our study involved 10 patients(11.3%) of which 9 were men and 1 was a woman, all undergoing shoulder and posterior neck defect reconstruction following malignancy excision with a trapezius flap from a total of 88 patients who underwent shoulder and posterior neck reconstruction. In our study period of 3 years with various reconstructive techniques, we observed a diverse array of postoperative outcomes. The mean age of the patient was 45.3 years, ranging from 30 to 60 years. The demographic, disease, complication, and management profiles of patients are shown (Table 1). Flap length ranged from 20 to 28 cm and flap width ranged from 6 to 8 cm in this series of cases.

Table 1.

Demographic, disease, flap size, complication, and management profiles of patients

S. no	Age/sex	Type of tumor	Flap size	Follow-up duration (months)	Complications	Management
1	40/F	Desmoid tumor posterior neck	24 × 8 cm	10	None	None
2	55/M	Squamous cell carcinoma posterior neck	25 × 8 cm	12	None	None
3	52/M	Spindle cell neoplasm left shoulder	28 × 7 cm	6	Seroma formation wound dehiscence	Conservative
4	38/M	Malignant fibrous histiocytoma right shoulder	28 × 8 cm	8	Partial flap necrosis	Flap revision and suturing
5	39/M	Squamous cell carcinoma posterior neck	25 × 8 cm	11	None	None
6	53/M	Dermatofibrosarcoma left shoulder	26 × 7 cm	12	None	None
7	55/M	Soft tissue sarcoma right shoulder	28 × 8 cm	10	Seroma formation	Conservative
8	52/M	Desmoid tumor posterior neck	28 × 7 cm	12	Recurrence	Re-excision and free flap reconstruction
9	30/M	Malignant melanoma posterior neck	26 × 6 cm	11	None	None
10	59/M	Squamous cell carcinoma posterior neck	20 × 8 cm	10	None	None

Of 10 patients, three patients had an SCC posterior neck; we proceeded with tumor excision and covered the defect with a pedicled trapezius muscle flap. All three patients had excellent post-operative recovery; she has been disease-free for almost 1 year with good cosmetic results.

One patient had malignant melanoma of the posterior neck, which is a rare site of occurrence, but after excision with a 2-cm margin, the defect had to be closed with a flap; hence, we chose the pedicled trapezius flap as our flap of choice. The patient had good cosmetic results and had a good recovery with post-operative complications.

In our series, predominant cases (6 out of 10) were soft tissue sarcoma of the posterior neck and shoulder region. Due to the aggressive nature of malignant soft tissue tumors, most of our complications following flap reconstruction happened in these cases. A patient with a Desmoid tumor of the posterior neck had a recurrence of the tumor after 8 months of initial surgery, and we managed it by re-excision and a free flap reconstruction. Two patients with soft tissue sarcoma of shoulder after reconstruction had seroma formation and one of them ended up in wound dehiscence, and both were managed conservatively. Follow-up of both patients was uneventful.

We had only one case with partial flap necrosis which was managed with excision and secondary suturing, which occurred probably due to tight closure due to difficulty in insetting the flap in the recipient site, in a case of a malignant fibrous histiocytoma right shoulder. On routine follow-up, the patient had no complications.

The post-excision defects in the shoulder and posterior scalp, with a mean size of 13 ± 2 × 6 ± 2 cm, pose significant challenges in reconstruction. In our study, we meticulously managed these challenging defects using the trapezius muscle flap technique. It was noted that all the donor flap site defects were closed primarily without tension. Donor site morbidity was analyzed by using VAS (visual analog scale), and most of the cases had scores less than 3, which encouraged us to use the trapezius flap more frequently. A case of a left shoulder dermatofibrosarcoma with trapezius muscle flap reconstruction (Figs. 1, 2, 3, 4, and 5) was done and showed excellent cosmetic results.

Fig. 1.

Left dermatofibrosarcoma left shoulder

Fig. 2.

Intraoperative picture showing the defect post excision

Fig. 3.

Marking of trapezius flap

Fig. 4.

Trapezius flap with vascular pedicle

Fig. 5.

Closure of defect with pedicled trapezius flap

It is noteworthy that 9 out of 10 patients had favorable long-term outcomes. The successful resolution of complications and the overall positive functional and aesthetic results (Fig. 6) underscore the efficacy of the Trapezius flap in Shoulder and posterior neck defect reconstruction following malignancy resection.

Fig. 6.

Long-term outcome of pedicled trapezius flap

Discussion

Shoulder and posterior neck tumors are a complex and challenging subset of oncological cases [5]. They can be difficult to diagnose due to their varied histopathology and location. The management of these tumors requires a comprehensive approach that considers factors like tumor type, size, and involvement of adjacent structures. Surgery is the primary treatment for localized shoulder and posterior neck tumors, with an aim for complete removal with clear margins. In cases where surgery is not possible or for palliative purposes, radiation therapy plays a crucial role in controlling local disease.

The trapezius muscle is one of the largest muscles in the body and has three parts: superior, middle, and inferior [6]. The superior part starts from the seventh cervical vertebra, the external occipital protuberance, and the ligamentum nuchae and ends at the clavicle [7]. The middle part originates from the seventh cervical and first three thoracic vertebrae and ends at the acromion and spine of the scapula. The inferior part arises from the remaining thoracic vertebrae and ends in an aponeurosis near the scapula. The trapezius muscle has two main functions [8]: it moves the scapula when the spinal segments are stable, and it moves the spine when the scapula is stable. The spinal accessory nerve provides innervation to the trapezius muscle.

The muscle’s blood supply comes from the transverse cervical artery’s superficial and deep branches, which usually arise from the thyrocervical trunk [9, 16]. The deep branch is sometimes referred to as an independent vessel arising directly from the subclavian artery, and there is a debate surrounding this. The TCA’s anatomy in the posterior triangle is highly variable, typically entering the trapezius muscle at the base of the neck and descending vertically along its deep surface [16]. The SCA, emerging from the TCA, runs lateral and superficial to the levator scapulae and rhomboid muscles, accompanying branches of the accessory nerve [10, 11]. The trapezius muscle flap design aligns with the SCA’s course, with the flap’s long axis centered between the spine and the medial border of the scapula.

The trapezius flap surgical technique involves positioning the patient in a prone or lateral decubitus position, depending on the location of the defect and the extent of dissection required. The flap is then designed based on the size and shape of the defect that needs to be reconstructed. The design may vary depending on whether the skin, muscle, or a combination of both is required for reconstruction. The trapezius muscle is then dissected from the surrounding structures such as the latissimus dorsi and rhomboid major muscles while preserving its vascular pedicle. The trapezius muscle vertebral attachments are divided, and the paraspinous perforators are ligated. It is important to remember that the TCA divides into superficial and deep arteries at the posterior aspect of the posterior triangle. The superficial branch runs on the undersurface of the trapezius and divides into ascending and descending branches [17, 18]. The descending branch supplies the mid and lower trapezius muscle and overlying skin. The ascending branch supplies the superior trapezius along with the occipital and paraspinous vessels [19]. During the procedure, careful dissection is performed to avoid injury to the accessory nerve, which runs through the substance of the muscle. Once the flap is adequately mobilized, it is transferred to the defect site and inset meticulously to ensure adequate coverage and vascularization. The donor site is closed primarily or with the use of skin grafts or local flaps, depending on the size and location of the defect.

The trapezius muscle flap is a versatile option that can be used for various applications, ranging from muscle-only to perforator-based skin flaps. It can be used as a bilateral flap or an osteomusculocutaneous trapezius flap [12, 20]. The muscle flap offers advantages like robust circulation, resistance to infections, and easy surgical techniques [13]. Compared to distant tissue transfer methods, it provides better aesthetic matching, easier surgical procedures, and a shorter operation time. Functional impairment can be minimized by preserving the upper part of the trapezius muscle and rhomboid muscles [14, 15].

However, limitations include the flap’s restricted width (8–10 cm) and potential donor site complications if a larger flap is needed. The trapezius muscle flap is considered safe within certain parameters, and clinical outcomes show minimal complications, with two cases of postoperative donor site seroma observed.

The retrospective analysis of 10 cases presented in this study highlights the utility of the trapezius muscle flap in the reconstruction of shoulder and posterior scalp defects following malignant tumor resection. The demographic and disease profiles of the patients, encompassing a predominantly male population with a mean age of 45.3 years, provide valuable insights into the application of the trapezius flap in this specific context. The inclusion of patients within the age range of 30 to 60 years reflects the versatility of this technique across various age groups.

The identified complications, such as donor site seroma, wound dehiscence, partial necrosis of the flap tip, and tumor recurrence in one patient, offer a realistic perspective on the challenges associated with the trapezius muscle flap. These complications, although present, are relatively low in occurrence, suggesting that the benefits of this surgical approach outweigh the risks in the majority of cases. The single instance of tumor recurrence underscores the importance of long-term follow-up and emphasizes the need for continued surveillance, especially in oncologic cases.

In our study, the decision to utilize the trapezius muscle flap for reconstruction of shoulder and posterior scalp defects following malignant tumor resection was primarily influenced by several factors, including the absence of a plastic surgeon at the time of surgery and patients financial constraints, and additionally, the trapezius muscle flap was chosen as the primary reconstructive option due to its inherent advantages, including proximity to the defect site, versatility, and reliability. The trapezius muscle flap provides a robust blood supply and a relatively straightforward surgical technique, making it a suitable choice for reconstruction, particularly in cases where more complex microsurgical procedures are not readily available.

The study found that despite some complications, the trapezius muscle flap is effective in achieving successful flap survival and functional recovery in 90% of cases. Only two patients developed donor site seroma, and the majority experienced good long-term results, indicating the reliability of this surgical technique in managing shoulder and posterior scalp defects. The post-excision defect mean size was 13 ± 2 × 6 ± 2 cm managed using the trapezius muscle flap technique. It was noted that all the donor flap site defects were closed primarily without tension. Donor site morbidity was analyzed by using VAS (visual analog scale), and most of the cases had scores less than 3. However, the study has some limitations such as the small sample size and the need for further exploration of vascular anatomy. Addressing these limitations in future research will help us better understand the trapezius muscle flap’s applicability and potential refinements.

Conclusion

This case series provides valuable insights into the successful use of the trapezius muscle flap for shoulder and posterior scalp defects following malignant tumor resection. The documented complications are minimal in comparison to the overall positive outcomes, making the trapezius muscle flap a viable and reliable option for reconstruction in this specific clinical scenario. Ongoing research and refinement of techniques will likely contribute to establishing the trapezius muscle flap as a standard and effective choice for shoulder and posterior scalp reconstruction.

Abbreviations

AJCC

American Joint Committee on Cancer

TNM

Tumor, node, metastasis

CECT

Contrast-enhanced computed tomography

CEMRI

Contrast-enhanced magnetic resonance imaging

TCA

Transverse cervical artery

DSA

Dorsal scapular artery

C

Cervical vertebrae

T

Thoracic vertebrae

VAS

Visual analog scale

Author Contribution

AB, MD, and KKL conceived the idea.

PMS, PP, and AB designed the study and laid the framework for data collection.

AB, PMS, DM, and KKL did data collection and data entry.

KKL and SS supervised data entry and did data analyses.

AB, SN, and SS laid down the framework for the paper and supervised data analysis.

AB and KKL wrote the manuscript.

SS and AB helped review literature.

KKL and PP helped in editing and formation of the final draft.

Funding

This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

Declarations

Ethics Approval

Approval from the Institutional Ethics Committee of SMS medical college, Jaipur was taken for the conduct of this study.

Consent to Participate

Well-informed consent from patients was taken.

Conflict of Interest

The authors declare no competing interests.