Pacinian corpuscle neuroma: A rare case report with review of Literature

The authors discuss an interesting case of a Pacinian corpuscle neuroma in the fi nger of a young woman who presented with severe digital pain. The clinical signs were very prominent. The patient had complete pain relief following excision of the tumor. Pacinian corpuscle neuromas are rare, with only about few cases reported in the literature. The histology, presenting features and associated conditions are discussed in detail. In addition to a neuroma or glomus tumor, Pacinian corpuscle hyperplasia should be considered in the differential diagnosis of digital or palmar pain of unknown etiology. Case Report Pacinian corpuscle neuroma: A rare case report with review of Literature Sujit Kumar Singh1*, Umesh Yadav2, Ajay Sheoran2, RC Siwach3, Ashish Devgan3, Kshitish Chandra Behera4, Amandeep Verma1 and Karunesh Ranjan1 1Junior Resident, Department of Orthopedics, Pt. BD Sharma PGIMS, Rohtak, India 2Assistant Professor, Department of Orthopedics, Pt. BD Sharma PGIMS, Rohtak 3Senior Professor, Department of Orthopedics, Pt. BD Sharma PGIMS, Rohtak 4Senior Resident, Department of Orthopedics, Pt. BD Sharma PGIMS, Rohtak Received: 03 June, 2020 Accepted: 26 June, 2020 Published: 27 June, 2020 *Corresponding author: Sujit Kumar Singh, Junior Resident, Department of Orthopedics, Pt. BD Sharma PGIMS, Rohtak, India, Tel: +91-9477943631; E-mail: ORCID: https://orcid.org/0000-0002-2285-6905

near the metacarpophalangeal joints (25% to 48%) and in the thenar and hypothenar regions (8% to 18%) [1]. A neuroma may sometimes arise from this Pacinian corpuscle. We present an interesting case of a woman with Pacinian corpuscle neuroma of the thumb.

Review of literature
Pacinian corpuscle neuroma is an uncommon lesion with a limited number of cases reported. This lesion can be called variably as Pacinian corpuscle hyperplasia or Pacinian corpuscle neuroma [2][3][4][5][6][7]. The most common site of this lesion is the hand, where it presents as painful swelling. A prior history of trauma may be elicited in a majority of the patients and it may be associated with foreign body reaction [8]. Presentation may vary from digital pain to macrodactly [2][3][4][5][6][7][8]. Differential diagnosis of glomus tumor should always be kept in mind when disease involves the digital pulp. Similar lesions have been described in other parts of the body as well.

Case presentation
A 32-year-old female patient presented to the Department of Orthopaedics with pain of right thumb since last 8 months.
The pain was diffuse and severe over whole of the thumb and was even tender to light touch. There was no history of previous pain. On examination, there was normal skin and nail complex.
Flexor tendons were intact with no compressibility, pulsations or thrill and no distal neurovascular defi cit. A provisional diagnosis of a Glomus tumour was made. Routine blood investigations, ECG, chest X-ray, X-ray of the right hand and an MRI were done. X-ray showed normal bone architecture.
MRI revealed an intensely enhancing T2 hyperintense lesion on medial aspect of nail bed suggestive of Glomus tumour ( Figure   2). Based on the reports excision and biopsy of the lesion was planned. A linear incision was made on the medial aspect under local anaesthesia using 2% lignocaine and tourniquet control ( Figure 3). Immediately in the subcutaneous plane, shiny clusters of mass were seen clumped together and they seemed to be under tension. All of the visible masses were excised.
Primary closure was performed. The excised mass was sent for histopathological examination. Histopathological features were consistent with a Pacinian corpuscle neuroma (Figures 4,5). Postoperative period was good. Patient was discharged on the 2nd postoperative day and skin sutures were removed on the 14th postoperative day. One month hence, the patient had complete pain relief. Finger movements were near normal.
Post operative period was uneventful and no recurrence was noted in post operative period.

Conclusion
When making a differential diagnosis of unexplained severe pain in the hand, Pacinian corpuscle should be considered in addition to benign tumors of non-neural origin, such as hemangiomas, fi bromas, ganglion cysts, mucoid cysts and angiolipomas, and neural origin, including schwannomas and glomus tumors, as the cause of a tender digital papule. Several autoimmune diseases such as gout, exostosis, and arthritis