Original Article |
Corresponding author: Edoardo Ipponi ( edward.ippo@gmail.com ) © 2024 Edoardo Ipponi, Elena Bechini, Martina Cordoni, Fabrizia Gentili, Francesco Rosario Campo, Fabio Cosseddu, Antonio D’Arienzo, Paolo Domenico Parchi, Lorenzo Andreani.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Ipponi E, Bechini E, Cordoni M, Gentili F, Campo FR, Cosseddu F, D’Arienzo A, Parchi PD, Andreani L (2024) Schwannomas of the upper limb: Clinical presentation, preoperative management and outcomes of surgical treatment. Folia Medica 66(5): 618-628. https://doi.org/10.3897/folmed.66.e135490
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Inroduction: Schwannomas are the most common tumors of the peripheral nervous system. Surgical eradication with excision or enucleation is the treatment for symptomatic and large schwannomas.
Aim: Few studies have investigated the clinical outcomes related to the surgical approach to schwannomas. Our study aims to evaluate the clinical and functional results of surgery for the treatment of upper limb schwannomas.
Materials and methods: Twenty-two cases of upper limb schwannomas were surgically treated in our institution between January 2016 and December 2023. All cases underwent preoperative and 6-month postoperative MRI. For each case, we recorded the diagnostic interval (symptom-diagnosis), symptoms (stenosis or sensory deficits, pain, and Tinel test), and both pre-and postoperative functional status (with DASH and MSTS scores). We also recorded complications and local recurrences.
Results: On average, the diagnosis was made 16.7 months after the onset of the first symptom. The mean preoperative MSTS, DASH, and MRC values were 27.9, 5.7, and 4.8, respectively. We had no intra-operative complications. After a mean follow-up of 43.1 months, MSTS, DASH were 29.7/30 and 0.7, respectively. No case developed local recurrences. No case recorded stenosis deficits at the last follow-up. Only one patient developed local paresthesia (9%), while two reported modest dysesthesias.
Conclusions: An adequate surgical approach, possibly preceded by a rapid diagnosis, can significantly improve the symptoms caused by schwannoma, restoring the functionality of the upper limb.
deficit, enucleation, functionality, resection, review
The schwannomas, also known as neurilemmomas or neurinomas, are the most common benign soft tissue neoplasms that originate from the peripheral nerve sheath.[
Once anamnestic and clinical findings suggest schwannoma, imaging evidence is necessary to investigate the lesion further. Although ultrasound evaluations can be useful and easy to perform, MRI remains the radiological investigation of choice to identify its nerve of origin and further orient toward the presumptive diagnosis of schwannoma that usually appears as a well-circumscribed and encapsulated mass, a heterogeneous signal.[
Once the presumptive diagnosis has been established, surgical treatment is the only available approach to remove the neoplastic mass. Surgeons are called to remove schwannomas as a whole to minimize the risk of local recurrence and preserve the continuity of the involved nerve, especially in the case of major nervous structures. For this reason, the operative treatment of choice is the enucleation of the neoplastic mass when it involves a major nerve or complete resection when the nerve is too thin to be preserved. The enucleation consists of a linear cut of the perineurium and a smooth dissection of the neoplastic mass from the nearby nervous bundles, that should be spared in order to preserve the nerve’s post-operative functionality.[
Due to the rarity of schwannomas arising from the upper limb, only a few studies available at the moment focus on clinical presentation and prognostic factors.[
This study evaluates the clinical impact of upper limb schwannomas, focusing on patients’ functionality. We also assessed the effectiveness of the surgical approach in reducing patients’ symptoms, restoring patients’ upper limbs’ performance, and increasing their quality of life.
This single-center retrospective study was conducted according to the ethical standards in the 1964 Declaration of Helsinki and its later amendments.
Our study consisted of a review of all schwannomas arising from the major nerves of the upper limb and treated with surgery in our institution between January 2016 and January 2024.
For each patient, we collected data regarding their age, gender, first symptom associated with the disease, and its date, alongside the date on which schwannoma was diagnosed. We reviewed the tumor’s localization in terms of the anatomical segment involved (shoulder, arm, elbow, forearm, wrist, or hand) and the nerve from which the neoplasm originated. The diagnostic interval, corresponding to the time between the onset of the first symptom and the definitive histological diagnosis, was recorded for each patient.
Our patients’ pre-operative functional status was evaluated using the Disability of Arm, Shoulder, and Hand (DASH) score and the Musculoskeletal Tumor Society (MSTS) score at the moment of hospitalization. Before surgery, the Medical Research Council (MRC) scale was used to assess the contractile strength of the muscular segments of the treated area, paying particular attention to those innervated by the involved nerve. In parallel, a Tinel-Hoffmann test and a careful examination of the deep and cutaneous sensitivity were practiced on every patient suspected of neurinoma before their intervention.
Each patient underwent a pre-operative MRI (Fig.
A schwannoma arising from the median nerve, in the anterior elbow. The neoplasm was circled both in a sagittal T1 scan (A) and in a transverse T2 scan (B).
In the surgical theater, before the surgical incision, lesions were localized under ultrasound guidance, in order to orientate the surgical approach to the tumor. Intra-operatively, the involved nerves were identified and isolated, and schwannomas were carefully enucleated, preserving the continuity of the involved nerves (Fig.
A schwannoma arose from the median nerve, localized in the distal anterior end of the arm. The neoplasm was exposed (A) and later enucleated, preserving the anatomical continuity of the nerve itself (B).
Surgical specimens (Fig.
All of our patients were treated with oral integration of lipoic acid, citicoline and vitamins B for 30 days after surgery in order to obtain an antioxidant, neurotrophic and neuroprotective effect.
Postoperative follow-up consisted of serial office visits, clinical evaluations, and postoperative MRIs performed within one month (clinical evaluation only) and later 6 and 12 months after surgery. Further evaluations were scheduled depending on the necessities of each single case.
Each complication with a grade II or higher, according to the Clavien-Dindo classification, was reported. Local recurrences and their eventual treatments were also recorded.
At each patient’s latest follow-up, we evaluated the presence of sensitive deficits, repeated the Tinel test, and assessed muscular strength according to the MRC scoring scale. We also recalculated the overall functional status of the treated upper limbs using the MSTS and the DASH score.
Statistical analysis was performed using Stata SE 13 (StataCorp LLC, College Station, TX). Statistical significance was set at 0.05 for all endpoints.
Twenty-two consecutive cases of schwannomas of the upper limbs were treated in our institution between January 2016 and December 2023. Our cohort included 11 females and as many males, with a mean age of 54.0 (38–78) at surgery.
Two cases (9%) had their lesion localized in the shoulder girdles, 6 (27%) in their arms and 5 (23%) in their elbows. The forearm was the location of 7 (32%) schwannomas, whereas the remaining two cases were diagnosed with schwannomas in their wrist and hand (9%). The most common nerve of origin for treated schwannomas was the radial nerve (10; 45%), followed by the ulnar (4; 18%) and the median nerve (3; 14%). In the remaining cases, schwannomas arose from the brachial plexus (2; 9%), the musculocutaneous nerve (2; 9%), and the anterior interosseous nerve (1; 5%). A summary of schwannomas’ localization is provided in Fig.
Only one of our cases (4%) had an incidental diagnosis without any sign attributable to the disease. The remaining 21 cases (96%) were brought to medical attention by the onset of symptoms attributable to the disease. The first symptom was palpable swelling in 19 cases (86%) and pain in the remaining 2 cases (10%). On average, the diagnosis was established 16.7 months after the onset of the first symptom. Eleven cases (50%) had a positive Tinel sign at the moment of patients’ hospitalization. According to a two-tailed T Student test, presence or absence of the Tinel sign did not represent a factor that influenced the diagnostic interval. The mean pre-operative MRC score was 4.8 (4-5), as five patients (23%) experienced a mild reduction in their muscular strength. Before surgery, 13 cases (59%) had developed dysesthesia or paresthesia; symptoms were mild in 10 (45%) and moderate in 3 cases (14%). The remaining nine patients (41%) did not complain of any sensitive deficit.
The overall functionality of our patients’ upper limbs was calculated using the MSTS and DASH scores before surgery. The mean pre-operative MSTS score was 27.9 (21-30), and the mean pre-operative DASH score was 5.7 (0-25).
The size of the neoplasms was assessed using the MRI scans and later confirmed on surgical specimens: the mean larger diameter was 3.8 cm (1.5–11.0). A Pearson correlation test stated that the larger the schwannomas were, the lower the MSTS score and the higher the DASH score was before surgery (p=0.0001).
Intra-operatively, surgeons could successfully enucleate all the treated schwannomas, preserving the continuity of all nerves. Histological evaluations confirmed the diagnosis of Schwannoma in each case.
None of our cases had major intra-operative or peri-operative complications.
The mean post-operative follow-up was 43.1 (6-92). Only one patient (Case 14) complained of increased sensitive deficits after surgery, passing from mild to moderate paresthesia and experiencing hand tingling that was not present before surgery. The sensitivity deficits of all the remaining cases with pre-operative deficits were reduced after surgical treatment, and only two patients (9%) had dysesthesia at their latest follow-up. According to a Fisher Exact test, the rate of sensitive deficits was significantly lower after surgery compared to the pre-operative records (p=0.0011).
No Tinel sign was recorded after surgery. Case 14 was also the only one to maintain a slight muscular strength impairment (MRC 4); the MRC score of the remaining cases was as high as 5.
The mean post-operative MSTS score was 29.7 (24-30). The difference between this value and the pre-operative one was statistically significant, as testified by a Pearson correlation test (p=0.0022).
The mean post-operative DASH score was 0.7 (0-16). According to a Pearson correlation test (p=0.0029), this value was significantly lower than the one recorded before surgery.
None of our cases was diagnosed with a local recurrence through their post-operative intercourse.
The characteristics of our cohort are summarized in Table
N | Sex | Age yrs | D.I. mos | Site | Nerve | Size cm | First sign | MSTS Pre | DASH Pre | Tinel sign Pre | MRC Pre | Sens. Deficit Pre | MSTS Post | DASH Post | Tinel sign Post | MRC Post | Sens. Deficit Post | L.R. | FU mos |
1 | F | 58 | 3 | Shoulder | Brachial plexus | 5.0 | Swelling | 27 | 7 | No | 5 | Mild | 30 | 0 | No | 5 | None | No | 81 |
2 | F | 38 | 3 | Shoulder | Brachial plexus | 7.0 | Swelling | 21 | 25 | No | 4 | Moderate | 29 | 0 | No | 5 | Mild | No | 6 |
3 | M | 77 | 36 | Arm | Musculocutaneous | 5.5 | Swelling | 27 | 7 | Yes | 4 | Mild | 30 | 0 | No | 5 | None | No | 87 |
4 | F | 65 | 18 | Arm | Musculocutaneous | 2.0 | Swelling | 30 | 0 | Yes | 5 | None | 30 | 0 | No | 5 | None | No | 7 |
5 | F | 51 | 28 | Arm | Radial | 5.8 | Swelling | 27 | 9 | Yes | 4 | Mild | 30 | 0 | No | 5 | None | No | 59 |
6 | M | 56 | - | Arm | Radial | 4.5 | None | 30 | 0 | No | 5 | None | 30 | 0 | No | 5 | None | No | 48 |
7 | M | 65 | 24 | Arm | Radial | 2.0 | Swelling | 30 | 0 | No | 5 | None | 30 | 0 | No | 5 | None | No | 43 |
8 | F | 54 | 36 | Arm | Radial | 4.0 | Swelling | 28 | 7 | Yes | 5 | Mild | 30 | 0 | No | 5 | None | No | 37 |
9 | M | 60 | 24 | Elbow | Anterior interosseous | 2.0 | Swelling | 30 | 0 | Yes | 5 | None | 30 | 0 | No | 5 | None | No | 18 |
10 | F | 48 | 24 | Elbow | Radial | 1.5 | Swelling | 28 | 9 | Yes | 5 | Mild | 30 | 0 | No | 5 | None | No | 36 |
11 | M | 41 | 18 | Elbow | Radial | 3.0 | Swelling | 29 | 0 | No | 5 | None | 30 | 0 | No | 5 | None | No | 30 |
12 | F | 45 | 24 | Elbow | Radial | 5.0 | Swelling | 28 | 2 | Yes | 5 | Mild | 30 | 0 | No | 5 | None | No | 21 |
13 | M | 59 | 12 | Elbow | Ulnar | 1.7 | Swelling | 30 | 0 | No | 5 | None | 30 | 0 | No | 5 | None | No | 75 |
14 | F | 40 | 6 | Forearm | Median | 1.5 | Swelling | 26 | 14 | No | 4 | Mild | 24 | 16 | No | 4 | Moderate | No | 27 |
15 | F | 59 | 3 | Forearm | Median | 1.8 | Swelling | 26 | 16 | Yes | 5 | Mild | 30 | 0 | No | 5 | None | No | 12 |
16 | F | 57 | 24 | Forearm | Radial | 4.6 | Pain | 27 | 9 | Yes | 5 | Moderate | 30 | 0 | No | 5 | None | No | 15 |
17 | M | 63 | 3 | Forearm | Radial (superficial) | 3.0 | Pain | 28 | 2 | Yes | 5 | Mild | 30 | 0 | No | 5 | None | No | 18 |
18 | M | 45 | 18 | Forearm | Ulnar | 1.3 | Swelling | 30 | 0 | No | 5 | None | 30 | 0 | No | 5 | None | No | 62 |
19 | M | 30 | 12 | Forearm | Ulnar | 11.0 | Swelling | 30 | 0 | No | 5 | None | 30 | 0 | No | 5 | None | No | 50 |
20 | F | 48 | 22 | Forearm | Ulnar | 6.5 | Swelling | 29 | 4 | No | 5 | None | 30 | 0 | No | 5 | None | No | 32 |
21 | M | 78 | 6 | Wrist | Radial (superficial) | 3.5 | Swelling | 28 | 4 | No | 5 | Mild | 30 | 0 | No | 5 | None | No | 92 |
22 | M | 41 | 6 | Hand | Median | 2.0 | Swelling | 26 | 11 | Yes | 4 | Moderate | 30 | 0 | No | 5 | None | No | 92 |
The clinical presentation of the schwannomas of the upper limb can include a large variety of signs and symptoms. Correctly evaluating signs and symptoms attributable to the disease is crucial to starting a proper diagnostic pathway and minimizing the risk of misdiagnosis. Although the number of studies in the literature on this topic is slowly but progressively increasing[
Resume of modern literature about curettage for hand enchondromas. The reported articles are the result of a combined research on the catalogs of PubMed, Scopus and Google scholar, searching for the words “upper limb” or “shoulder” or “arm” or “elbow” or “forearm” or “wrist” or “hand” and “schwannoma”. Only studies published and indexed between 2000 and March 2024 were included in our list. Case reports were excluded.
Article | Year | N | Sites | Nerves | Size cm | Diagn. Interval mos | (Pre) Tinel | (Pre) Pain | (Pre) Deficit | (Pre) MSTS | (Pre) DASH | (Post) Tinel | (Pos) Pain | (Post) Deficit | (Post) MSTS | (Post) DASH | Local Recurr. | FU mos |
Maiuri et al.[16] | 2001 | 4 | 4 Shoulder | 4 Brachial Pl. | 4.5 | 8.7 | - | 50% | 25% | - | - | - | 0 | 0 | - | - | 0 | 65.1 |
Takase et al.[6] | 2004 | 20 | 1 Shoulder 5 Arm 9 Forearm 4 Wrist 1 Hand | 4 Ulnar 7 Median 4 Radial 4 Other | 1.0–5.5 | 43.1 | 80% | 30% | 20% | - | - | - | - | 10% | - | - | - | 42.0 |
Ozdemir et al.[17] | 2005 | 14 | 4 Wrist 10 Hand | 4 Ulnar 10 Median | 0.5–7.0 | 25.0 | 71% | 29% | 50% | - | - | 0 | - | 7.1% | - | - | 0 | 151.2 |
Sawada et al.[12] | 2006 | 13 | 3 Shoulder 3 Arm 4 Elbow 1 Forearm 2 Wrist 12 Hand | 3 Brachial Pl. 2 Ulnar 4 Median 3 Radial 1 Other | 2.9 | 48.0 | 61% | 33% | 22% | - | - | - | - | 33% | - | - | 0 | 11.3 |
Knight et al.[2] | 2007 | 170 | - | 94 Brachial Pl. 35 Ulnar 16 Median 14 Radial 1 Musculocut. 10 Other | 3.4 | - | 81% | 31% | 6% | - | - | - | 2.5% | 3% | - | - | 1% | 12 - 240 |
Tang et al.[3] | 2013 | 8 | 2 Shoulder 1 Forearm 3 Wrist 2 Hand | 1 Brachial Pl. 3 Ulnar 2 Median 1 Radial 1 Other | - | 88% | - | - | - | - | - | - | - | - | - | - | - | |
Lai et al.[13] | 2013 | 12 | 1 Shoulder 2 Arm 2 Forearm 3 Wrist 4 Hand | 3 Ulnar 9 Median 1 Other | 4.4 | 57 | - | - | - | - | - | - | - | 36% | - | - | 0 | 21.9 |
Lee et al.[14] | 2014 | 7 | - | 2 Brachial Plexus 3 Median 2 Radial | 3.0 | - | 43% | 14% | 43% | - | - | - | 0 | 27% | - | - | 0 | 37.2 |
Gosk et al.[5] | 2014 | 32 | 6 Shoulder 7 Arm 3 Elbow 5 Forearm 4 Wrist 6 Hand | 11 Ulnar 5 Median 7 Radial 2 Musculocut. 7 Other | 1.0–18.0 | - | 92% | 77% | 77% | - | - | 8% | 0 | 23% | - | - | 0 | 12+ |
Adani et al.[18] | 2014 | 34 | 7 Arm 14 Elbow and Forearm 13 Wrist and Hand | 15 Ulnar 9 Median 2 Radial 1 Musculocut. 7 Other | 32.0 | 68% | 35% | 41% | - | - | - | 3% | 3% | - | - | 0 | 12 | |
Lee & Yoon[15] | 2017 | 8 | Hand | - | 3.2 | 0.5 - 2 | 12% | 50% | - | - | - | - | 0 | 0 | - | - | - | - |
Galbiatti et al.[8] | 2020 | 14 | 1 Shoulder 4 Arm 3 Forearm 6 Hand | 7 Ulnar 2 Median 3 Radial 1 Musculocut. 1 Other | 3.3 | - | 43% | 50% | 50% | - | - | - | - | 0 | - | - | 0 | - |
Zyluk & Owczarska[9] | 2021 | 12 | 5 Forearm 2 Wrist 5 Hand | 2 Ulnar 3 Median 2 Radial 5 Other | - | 30 | 33% | - | - | - | - | - | - | 17% | - | - | 17% | 50.4 |
El Sayed et al.[10] | 2022 | 63 | 6 Shoulder 16 Arm 5 Elbow 14 Forearm 10 Wrist 12 Hand | 1 Brachial Pl. 15 Ulnar 20 Median 14 Radial 1 Musculocut. 12 Other | 1.6 | 21 | 55% | 50% | 80% | - | - | 7% | 5% | 19% | - | - | 1% | 5 |
Pertea et al.[4] | 2022 | 17 | 1 Shoulder 3 Arm 7 Forearm 1 Wrist 5 Hand | 7 Ulnar 4 Median 2 Radial 4 Other | 0.7–7.5 | - | 100% | 18% | 88% | - | - | - | 0 | 0 | - | - | 0 | 24 |
Istefan et al.[11] | 2023 | 30 | 3 Shoulder 6 Arm 2 Elbow 12 Forearm 7 Hand | 10 Ulnar 15 Median 5 Other | 1.9 | 12 | - | 69% | 83% | - | - | - | 30% | 17% | - | - | 3% | 3-18 |
Raj et al.[19] | 2024 | 24 | - | 4 Axillary 10 Ulnar 7 Median 3 Radial | 3.5 | 15.8 | - | 72% | 31% | - | 6.1 | - | 5.6% | 35% | - | 6.2 | 0 | 69.4 |
Ipponi et al. | 22 | 2 Shoulder 6 Arm 5 Elbow 7 Forearm 1 Wrist 1 Hand | 2 Brachial Pl. 2 Musculocut. 4 Ulnar 4 Median 10 Radial | 3.8 | 16.7 | 50% | 59% | 59% | 27.9 | 5.7 | 0 | 0 | 9% | 29.7 | 0.7 | 0 | 43.1 |
On the other hand, Gosk et al.[
The Tinel sign still represents one of the most iconic and broadly used tests for the clinical assessment of neurinomas. Although our prevalence of 50% ranks among the lowest reported in modern literature for relatively large cohorts (33-100%).[
While several authors described the frequency of single symptoms, modern literature severely lacks evidence about the global impact of schwannomas on upper limb functionality. Few studies have provided evidence based on widely used scoring systems, such as the DASH or MSTS scores. Raj et al.[
Surgical resection of the neoplastic mass, performed with careful enucleation from the involved nerve, is a safe procedure, as confirmed by the absence of major intra-operative or peri-operative complications in our cohort.
Its effectiveness, already confirmed by previous studies, was also evidenced in our population by the significant reduction in sensitive symptoms after surgery (p=0.0011). Furthermore, both the MSTS (29.7) and the DASH score (0.7) got significantly better after surgery, marking an almost complete remission of the limitations caused by the disease. This result differs from the findings of Raj et al.[
We acknowledge that our study had some limitations. The rarity of these tumors did not allow us to operate on broader populations, which partially limited the statistical significance of some of the data associations we wanted to investigate at the beginning of our research. Another limitation is represented by the retrospective nature of our study, which did not allow the complete standardization of the post-operative follow-up procedures for each patient.
Despite these limitations, our study provides significant information on the clinical presentation of upper limb schwannomas and the clinical and functional outcomes that follow their treatment with surgical enucleation. To this date, diagnosing the schwannomas of the upper limb may still represent a challenge, especially for those who lack direct experience in this field. However, once a correct diagnosis has been established, surgical resection represents a reliable and effective surgical treatment both to remove the neoplasm and provide symptom relief.
The enucleation, performed to preserve the continuity of the nerve, can substantially reduce pre-operative symptoms and restore the upper limb’s functionality, allowing patients to return to their previous activities of daily living, thereby increasing their quality of life.
The authors have no support to report.
The authors have no funding to report.
The authors have declared that no competing interests exist.