Main Article Content
Schwannoma, Neurinoma, Lower Limb, Tibial Nerve, Functionality
BACKGROUND AND AIM OF THE WORK: Schwannomas of the lower limb are uncommon benign tumors and those arising from Tibial Nerve are particularly rare. Due to their rarity, today there is still paucity of studies about surgical treatment of Tibial Nerve schwannomas. We report our experience on the topic, with particular attention to clinical presentation and lower limbs overall functionality before and after treatment.
MATERIALS AND METHODS: Time between symptoms outbreak and diagnosis, as well as pre- operative tumor size were evaluated for each case. Pre-operative and post-operative overall lower limb functionality were assessed using both MSTS and LEFS scores. Sensitive symptoms and muscular strength were also evaluated before and after surgery.
RESULTS:7 patients were included in our study. The mean follow-up was 22.9 months. Average diagnostic delay was 8 months and tumor size was 29.3mm. Before surgery each patient had positive Hoffmann-Tinel sign and an at least mild paresthesia, 4 cases had slight reduction of muscular strength. Pre-operative MSTS score was 24.4 and LEFS score was 64.7. Tumor size and diagnostic delay were associated with pre-operative functionality. No major local complication was recorded during or after surgery. Each patient with pre-operative sensitive or motorial deficit benefited the effects of surgical treatment.
CONCLUSIONS: Our cases suggest early diagnosis could reduce the impact of the disease on patients’ activities of daily living and quality of life. Surgery, for its part, represents a safe and reliable approach to Tibial Nerve schwannomas with good chances of clinical and functional remission.
2. Jack CM, Jones G, Edwards MR, Singh SK. A case report of three peripheral schwannomas attached to the Achilles paratenon. Foot (Edinb). 2010; 20:78–80.
3. Knight DMA, Birch R, Pringle J. Benign solitary schwannomas: a review of 234 cases. J Bone Joint Surg [Br] 2007;89-B:382-7.
4. Birch R, Bonney G, Wynn Parry CB. The peripheral nervous system and neoplastic disease. In: Surgical disorders of peripheral nerves. Edinburgh: Churchill Livingstone, 1998:335-52.
5. Carvajal J, Cuartas E, Qadir R, Levi A, Temple T. Peripheral nerve sheath tumors of the foot and ankle. Foot Ankle Int 2011;32:163–7.
6. Jha AJ, Basetty CR, Viner GC, Tedder C, Shah A. Posterior Tibial Nerve Schwannoma Presenting as Tarsal Tunnel Syndrome. Cureus. 2019 Aug 1;11(8):e5303
7. Watanabe K, Fukuzawa T, Mitsui K. Tarsal Tunnel Syndrome Caused by a Schwannoma of the Posterior Tibial Nerve. Acta Med Okayama. 2018 Feb;72(1):77-80.
8. Buchanan V, Rawat M. Schwannoma of the Posterior Tibial Nerve. J Orthop Sports Phys Ther. 2020 Feb; 50(2):111.
9. Nawabi DH, Sinisi M. Schwannoma of the posterior tibial nerve: the problem of delay in diagnosis. J Bone Joint Surg Br. 2007 Jun;89(6):814-6.
10. Albert P, Patel J, Badawy K, Weissinger W, Brenner M, Bourhill I, Parnell J. Peripheral Nerve Schwannoma: A Review of Varying Clinical Presentations and Imaging Findings. J Foot Ankle Surg. 2017 May-Jun;56(3): 632-637.
11. Tladi MJ, Saragas NP, Ferrao PN, Strydom A. Schwannoma and neurofibroma of the posterior tibial nerve presenting as tarsal tunnel syndrome: review of the literature with two case reports. Foot (Edinb). 2017 Aug; 32:22-26.
12. Mehta SP, Fulton A, Quach C, et al. Measurement Properties of the Lower Extremity Functional Scale: A Systematic Review. J Orthop Sports Phys Ther. 2016 Mar; 46(3): 200-16.
13. Larson ST, Wilbur J. Muscle Weakness in Adults: Evaluation and Differential Diagnosis. Am Fam Physician. 2020 Jan 15; 101(2): 95-108.
14. Paternostro-Sluga T, Grim-Stieger M, Posch M, et al. Reliability and validity of the Medical Research Council (MRC) scale and a modified scale for testing muscle strength in patients with radial palsy. J Rehabil Med. 2008 Aug; 40(8): 665-71.
15. Ishizuka K, Uehara T, Yokokawa D, Noda K, Ikusaka M. Hoffmann-Tinel sign and entrapment neuropathy. QJM. 2021 Feb 18; 114(1): 45-46.
16. Clavien PA, Barkun J, de Oliveira ML, et al. The Clavien-Dindo classification of surgical complications: five- year experience. Ann Surg. 2009 Aug;250(2):187-96
17. Patel AT, Gaines K and Malamut R: Usefulness of electrodiagnos- tic techniques in the evaluation of suspected tarsal tunnel syndrome: an evidence-based review. Muscle Nerve. 2005; 32: 236- 240
18. Stramare R, Beltrame V, Gazzola M, Gerardi M, Scattolin G, Coran A, Faccinetto A, Rastrelli M, Rossi CR. Imaging of soft tissue tumors. J Magn Reson Imaging. 2012; 37:791-804.
19. Murphey MD, Smith WS, Smith SE, Kransdorf MJ, Temple HT. Imaging of musculoskeletal neurogenic tumors: radiologic-pathologic correlation. Radiographics. 1999; 19:1253–1280.