Lipoma of the supraspinatus muscle causing impingement syndrome: a case report

Intramuscular lipomas posing diagnostic and pre-operative counselling challenges in a low-resource setting: A case series

INTRODUCTION

Intramuscular lipomas (IMLs) are uncommon primary adipose tissue tumours deep within the muscle. A high likelihood of misdiagnosing them as other benign and malignant masses necessitates imaging studies to confirm the diagnosis and plan treatment. Ultrasonography is useful but CT and MRI provide a more accurate diagnosis. While diagnostic tests are suitable, they may not always be accessible or affordable in low-resource settings. We present three cases of IMLs that emphasise the difficulties posed by limited resources and the significance of a comprehensive medical history and physical examination in low-resource settings.

PRESENTATION OF CASES

The patients included a 57-year-old male with a distal right thigh mass, a 65-year-old female with a proximal right thigh mass, and a 60-year-old female with a mass at the left scapular area. The three patients underwent surgical excision and had an uneventful postoperative course, with no reported recurrence during their ongoing follow-up.

DISCUSSION

The management of IMLs is not complicated if the requisite resources are available. Conversely, in low-resource settings with limited diagnostic facilities and human expertise, management may take a challenging path. Patient 1, despite undergoing diagnostic tests confirming IML, initially declined treatment due to challenges with pre-operative counselling. Patients 2 and 3 lacked health insurance and could not afford diagnostic imaging tests.

CONCLUSION

Healthcare professionals in low-resource settings should familiarise themselves with the clinical characteristics and pathology of IMLs to minimise misdiagnosis and ensure appropriate counselling is provided to patients. IMLs are slow-growing mostly asymptomatic benign swelling. On physical examination, they are usually non-tender, soft, masses, not fixed to the bed or overlying tissue. The overlying skin is normal and lymphadenopathy is absent.

Lipoma of the Teres Minor in Rotator Cuff Arthropathy-A Case Report

Although lipomas are the most common mesenchymal tumors, the intramuscular type is rare. We report the case of a patient with rotator cuff arthropathy with a lipoma in the teres minor. Wide surgical excision and total shoulder arthroplasty with reverse prosthesis was performed and 18 months of follow up showed excellent results with any recurrence. The teres minor is extremely important for the proper function of a reverse prosthesis, and lipoma growth in the muscular belly can compromise the functionality of the prosthesis. To the best of our knowledge, this is the first case report of a rotator cuff arthropathy with a lipoma in the teres minor.

Subdeltoid Lipoma Associated With Subscapularis Tear Successfully Treated With Arthroscopic Resection and Cuff Repair: A Case Report

A 61-year-old male patient presented with left shoulder pain and an associated lump. Magnetic resonance imaging revealed a subscapularis tear, and subdeltoid lipoma obliterated its insertion. He was successfully treated with arthroscopic subscapularis repair and resection of mass simultaneously.To the authors' knowledge, this will be the first documented case of lipoma occurring under the deltoid muscle associated with the subscapularis tear. The reported arthroscopic approach for resection of the subdeltoid lipoma provides a complete removal, minimal muscle dissection, limited surgical scar, and satisfying functional outcomes. Therefore, it may be considered an option for benign tumor resection in this area.

Combined arthroscopic and open operative management of an intramuscular supraspinatus lipoma in the treatment of subacromial impingement syndrome: A case report

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Subacromial impingement syndrome encompasses a spectrum of pathologies.

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Further investigation is warranted beyond simple imaging when the pathology is not apparent.

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Benign lipomas can be diagnosed as the cause of subacromial impingement syndrome using MRI.

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Combined arthroscopic and open approach allows for multifaceted management in one procedure.

Introduction

Subacromial impingement syndrome (SAIS) is one cause of shoulder pain and encompasses a spectrum of pathologies and is not an isolated entity.

Presentation of case

We present a rare case where a 40 year old male presented with a 3 year history of right shoulder tip pain with limited abduction to 30°, external rotation to 45°, preserved internal rotation and forward flexion and a painful arc with positive Neers and Hawkins-Kennedy signs for impingement consistent with SAIS. The presentation occurred in the setting of a supraspinatus intramuscular lipoma demonstrated on shoulder MRI. This was managed operatively with a combined arthroscopic and open approach to allow performance of a bursectomy, debridement of mild acromioclavicular joint degeneration and lipoma excision. The patient was discharged on the first post-operative day. He was managed in a sling for 4 weeks with a graduated exercise program over the first 12 weeks with full shoulder strength and function maintained at 12 months.

Discussion

Lipoma as a cause of SAIS is rare but an important diagnosis that needs to be considered in the preoperative evaluation of SAIS to guide appropriately targeted surgical management.

Conclusion

This case reinforces the diversity of pathologies in SAIS and the breadth of differential diagnoses that need to be considered when evaluating and determining the appropriate surgical approach to maximise chance of symptom resolution in SAIS.

Subacromial lipoma causing shoulder impingement syndrome

Subacromial lipoma represents a rare cause of subacromial impingement syndrome (SIS). A 49-year-old male patient presented to clinic with progressive right shoulder pain and limited movement, ongoing for approximately 1 month. Magnetic resonance imaging (MRI) revealed a lesion, compatible with lipoma, extending through subacromial space and pressing on supraspinatus muscle. After histopathological verification of lipoma, mass was excised. Postoperatively, patient completed 1 month physical therapy and rehabilitation program. Patient was free of pain at 4-month follow-up. Subacromial lipoma should be included in differential diagnosis of SIS for patients unresponsive to conservative treatment; MRI is very useful to determine precise etiology and inform surgical treatment.

Painful Intramuscular Lipoma of the Infraspinatus: Unusual Location and Presentation

Intramuscular lipomas are considered a rare type of benign lipomas. They are usually located deeper and are less palpable than subcutaneous lipomas. A painful presentation with no palpable mass will make clinical diagnosis difficult; in these cases, further imaging should be considered. Only a small number of cases of intramuscular lipomas present with pain; these are located in the supraspinatus and deltoid muscles. To the authors' knowledge, there have been no previous reports of painful intramuscular lipomas involving the infraspinatus muscle. This article describes a case of intramuscular lipoma uniquely located in the infraspinatus muscle and presenting with shoulder pain. A 49-year-old woman presented with 2 months of left shoulder pain. There was no history of preceding trauma. Pain was aggravated by lying on the left shoulder and by the hand behind the back similar to Crass position. On the physical examination, her shoulder joint range of motion was slightly decreased. Simple radiography showed no significant abnormality, but ultrasonography revealed a hyperechogenic mass within the infraspinatus muscle. There was focal tenderness over the mass, but definite palpation of the mass was not possible. Magnetic resonance imaging revealed a well-circumscribed, homogeneous lesion measuring 43 × 28 × 16 mm within the infraspinatus muscle, leading to a diagnosis of intramuscular lipoma. Her pain was not improved with medication, suprascapular nerve block, and steroid injections. Finally, surgical intervention was done and intramuscular lipoma was confirmed by specimen. After excision, her shoulder pain was improved and resolved.

Lipoma in the subscapularis muscle causing scapular malposition

A 70-year-old woman had pain and fatigability of her left shoulder with asymmetric scapular position. The medial border of the scapula was more prominent in the left side compared to the right scapula, and scapular motion was different between sides. Magnetic resonance imaging showed a mass on the ventral surface of the scapula. Tumour resection was performed through the medial approach, and the tissue samples were found to be a lipoma with a pathological examination. Post-operatively, her pain immediately disappeared. Two years after surgery, no recurrence of the tumour had been found. Soft tissue tumours have never been reported as a cause of scapular malposition or winging. We reported a case with scapular malposition and dyskinesis caused by lipoma in the subscapularis muscle. Surgical resection successfully relieved her symptoms and improved the scapular motion. Soft tissue tumour occurring in the subscapularis muscle could possibly cause abnormal scapular position and motion.

Arthroscopic Marginal Resection of a Lipoma of the Supraspinatus Muscle in the Subacromial Space

Subacromial impingement syndrome is a common cause of shoulder pain in young adults and seniors at present. The etiology of this syndrome is associated with several shoulder disorders, most related to aging, overhead activities, and overuse. The subacromial space is well circumscribed and limited in size, and soft-tissue growing lesions, such as tumors, can endanger the normal function of the shoulder girdle. We present a case of shoulder impingement syndrome caused by an intramuscular lipoma of the supraspinatus muscle in the subacromial space in a 50-year-old male bank manager. Radiographs, magnetic resonance imaging, and a computed tomography scan showed a well-circumscribed soft-tissue tumor at the supraspinatus-musculotendinous junction. It was arthroscopically inspected and dissected and complete marginal excision was performed through a conventional augmented anterolateral portal, avoiding the need to open the trapezius fascia or perform an acromial osteotomy. Microscopic study showed a benign lipoma, and the shoulder function of the patient was fully recovered after a rehabilitation period of 4 months. This less invasive technique shows similar results to conventional open surgery.

Intramuscular lipoma: a review of the literature

Lipomas are the most common type of soft tissue mesenchymal tumors. They are typically located subcutaneously and consist of mature fatty tissue. When they occur under the enclosing fascia, they are called deep-seated lipomas. Infrequently, lipomas can arise inside the muscle and are called intramuscular lipomas. Intramuscular lipomas have been commonly investigated and categorized in the same group as other deep-seated and superficial lipomatous lesions. Their clinical, histological and imaging characteristics may resemble well-differentiated liposarcomas, further adding to the difficulties in the differential diagnosis. This article summarizes the available literature and describes the typical epidemiological, pathological and clinical features of intramuscular lipomas, as well as delineating their treatment and prognosis.

Subdeltoid lipoma causing shoulder impingement syndrome - a case report

The impingement syndrome is defined by the compression of the rotator cuff tendons against the coracoacromial arch. Several factors contribute to this condition and they are classified as structural or functional factors. The former are changes in the coracoacromial arch, proximal humerus, bursa and rotator cuff, and the latter are related to the mechanism of the upper limb by means of synchronized activity and balanced between the rotator cuff and scapular girdle muscles. The authors report here a case of parosteal lipoma of the proximal humerus, located between the muscles deltoid, teres minor and infraspinatus causing clinical signs of impingement. It is a rare occurrence, characterized as a structural cause for the onset of this symptom.

Subacromial impingement syndrome caused by a voluminous subdeltoid lipoma

Subacromial impingement syndrome is a clinical diagnosis encompassing a spectrum of possible etiologies, including subacromial bursitis, rotator cuff tendinopathy, and partial- to full-thickness rotator cuff tears. This report presents an unusual case of subdeltoid lipoma causing extrinsic compression and subacromial impingement syndrome. The patient, a 60-year-old man, presented to our institution with a few years' history of nontraumatic, posteriorly localized throbbing pain in his right shoulder. Despite a well-followed 6-months physiotherapy program, the patient was still suffering from his right shoulder. The MRI scan revealed a well-circumscribed 6 cm × 2 cm × 5 cm homogenous lesion compatible with a subdeltoid intermuscular lipoma. The mass was excised en bloc, and subsequent histopathologic examination confirmed a benign lipoma. At 6-months follow-up, the patient was asymptomatic with a complete return to his activities. Based on this case and a review of the literature, a subacromial lipoma has to be included in the differential diagnosis of a subacromial impingement syndrome refractory to nonoperative treatment. Complementary imaging modalities are required only after a failed conservative management to assess the exact etiology and successfully direct the surgical treatment.

Subacromial impingement syndrome in a patient with hereditary multiple exostosis: a case report

Background

Hereditary multiple exostosis (HME) is characterised by multiple osteochondromas that are distributed throughout the skeleton, invariably involving the shoulder girdle. Tumours within the subacromial space can cause secondary irritation of the rotator cuff and result in subacromial impingement syndrome.

Case presentation

We describe a 19 year old female patient with HME who presented with subacromial impingement syndrome secondary to a benign exostosis originating from the spine of the scapular and projecting into the subacromial space.

Conclusion

The unique aspects of this report was that the origin of the exostosis, which was not observed on early standard radiographs of the shoulder, and the use of arthroscopic excision of the exostosis. Hence we believe a low threshold for additional imaging, such as a magnetic resonance imaging, should be considered for patients with HME with subacromial impingement syndrome to ensure a symptomatic exostosis is not neglected. Arthroscopic excision of a benign subacromial exostosis is effective, offering a minimally invasive approach with relief of the patient’s symptoms.

Subacromial impingement syndrome secondary to scapulothoracic dyskinesia

The authors describe two cases of subacromial impingement syndrome of the shoulder secondary to scapular dyskinesia caused by a tumor in young adults. The two tumors, an osteochondroma and a ganglion, were located in the scapulothoracic joint and inhibited normal kinesis of the scapula during arm motion.

Surgical treatment of intramuscular, infiltrating lipoma

Lipoma may occasionally be found within the muscle, which is the intramuscular, infiltrating lipoma. Intramuscular, infiltrating lipoma is an uncommon lesion, and local recurrence can be expected if the surgical margin is not clear. We report 8 patients in a 2-year period diagnosed with intramuscular, infiltrating lipoma who were treated by marginal excision combined with wide excision in the Department of Orthopaedic Surgery, Changhua Christian Hospital. The surgical results were satisfactory, and no local recurrence was noted in an average followup period of 40 months. Surgical excision is the best way to treat the symptomatic intramuscular, infiltrating lipoma. Careful preoperative evaluation and complete tumor excision with clear margins are most important to ensure successful surgical results.