Retrospective Cohort Study
Copyright ©The Author(s) 2021. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Orthop. Oct 18, 2021; 12(10): 760-767
Published online Oct 18, 2021. doi: 10.5312/wjo.v12.i10.760
Clinical outcome after surgery on schwannomas in the extremities
Andreas Saine Granlund, Michala Skovlund Sørensen, Claus Lindkær Jensen, Birthe Højlund Bech, Michael Mørk Petersen
Andreas Saine Granlund, Musculoskeletal Tumor Section, Department of Orthopedic Surgery, Copenhagen University Hospital, Rigshospitalet, Copenhagen 2100, Denmark
Michala Skovlund Sørensen, Department of Orthopedic Surgery, Copenhagen University Hospital, Copenhagen 2200, Denmark
Claus Lindkær Jensen, Michael Mørk Petersen, Musculoskeletal Tumor Section, Department of Orthopedic Surgery, University of Copenhagen, Copenhagen 2100, Denmark
Birthe Højlund Bech, Department of Radiology, Rigshospitalet, University of Copenhagen, Copenhagen 2100, Denmark
Author contributions: Granlund AS performed the research and wrote the paper; Sørensen MS made the protocol, statistics and supervised the report; Jensen CL gave surgical inputs and supervised the report; Bech BH performed and examined the radiological scanning; Petersen MM supervised the research and acknowledged the final report.
Institutional review board statement: The study was reviewed and approved by the University of Copenhagen Review Board, No. RH-2016-144.
Informed consent statement: All study participants or their legal guardian provided informed written consent about personal and medical data collection prior to study enrolment.
Conflict-of-interest statement: All authors have nothing to disclose.
Data sharing statement: Statistical code and dataset available from the corresponding author at
STROBE statement: The authors have read the STROBE Statement-checklist of items, and the manuscript was prepared and revised according to the STROBE Statement-checklist of items.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See:
Corresponding author: Andreas Saine Granlund, MD, Instructor, Surgeon, Musculoskeletal Tumor Section, Department of Orthopedic Surgery, Copenhagen University Hospital, Rigshospitalet, Blegdamsvej 9, Copenhagen 2100, Denmark.
Received: February 5, 2021
Peer-review started: February 5, 2021
First decision: May 3, 2021
Revised: May 16, 2021
Accepted: September 8, 2021
Article in press: September 8, 2021
Published online: October 18, 2021

Schwannoma is a benign, encapsulated and slowly growing tumor originating from Schwann cells and is rarely seen in the peripheral nerve system. Typical symptoms are soreness, radiating pain and sensory loss combined with a soft tissue mass.


To evaluate pre- and postoperative symptoms in patients operated for schwannomas in the extremities and investigate the rate of malignant transformation.


In this single center retrospective study design, all patients who had surgery for a benign schwannoma in the extremities from May 1997 to January 2018 were included. The location of the tumor in the extremities was divided into five groups; forearm, arm, shoulder, thigh and leg including foot. The locations of the tumor in the nerves were also categorized as either; proximal, distal, minor or major nerve. During the pre- and postoperative clinical evaluation, symptoms were classified as paresthesia, local pain, radiating pain, swelling, impairment of mobility/strength and asymptomatic tumors that were found incidentally (with magnetic resonance imaging). The patients were evaluated after surgery using the following categories: Asymptomatic or symptomatic patients (radiating and/or local pain) and those with complications. The follow up period was from the time of surgery until last examination of the particular physician. Multivariate logistic regression analysis was performed to identify independent prognostic factors for postoperative significant symptoms at follow-up.


We identified 858 cases from the institutional pathology register. We excluded cases with duplicate diagnoses (n = 407), pathology not including schwannomas (n = 157), lesions involving the torso, spine and neck (n = 150) leaving 144 patients for further analysis. In this group 99 patients underwent surgery and there were five complications recorded: 2 infections (treated with antibiotics) and 3 nerve palsies (2 involving the radial nerve and one involving the median nerve) that recovered spontaneously. At the end of follow-up, 1.4 mo (range 0.5-76) postoperatively, we recorded a post-operative decrease in clinical symptoms: Local pain 76% (6/25), radiating pain 97% (2/45), swelling 20% (8/10). Symptoms of paresthesia increased by 2.8% (37/36) and there was no change in motor weakness before and after surgery 1% (1/1). Multivariate analysis showed that tumors located within minor nerves had a significantly higher prevalence of postoperative symptoms compared with tumors in major nerves (odds ratio: 2.63; confidence intervals: 1.22-6.42, P = 0.029). One patient with schwannoma diagnosed by needle biopsy was diagnosed to have malignant transformation diagnosed in the surgically removed tumor. No local recurrences were reported.


Surgery of schwannomas can be conducted with low risk of postoperative complications, acceptable decrease in clinical symptoms and risk of malignant transformation is low.

Keywords: Schwannoma, Extremities, Surgery, Removal, Symptoms, Outcome

Core Tip: Schwannoma is a benign slowly growing tumor which is most common in the central nerve system. Peripheral schwannomas can give symptoms as numbness, local- and radiating pain. Recent studies proves surgical excision can be made with low expectations for complications and a high rate of remission. Never the less, some patients show up with consisting and significant symptoms after surgery. Our study showed that location of tumor on the nerve is of importance when evaluating patients’ clinical symptoms post-operatively.