Invest Clin 63(4): 400 - 413, 2022 https://doi.org/10.54817/IC.v63n4a07

Corresponding author. Fei Xie. Department of Hand Surgery, Honghui Hospital, Xi’an Jiaotong University, Xi’an

City, 710054, Shaanxi Province, China. Fax: 029-85260965, Tel: +86 15929997740. E- mail: xief684491@163.com

Fibrolipomatous hamartoma of the median

nerve: a case report and literature review.

You-Ting Dang

, Xue-Hai Ou

, Qiang Wang

, Yun-Ping Zhou

, Deng-Ke Wei

and Fei Xie

Department of Pediatric Orthopedics, Honghui Hospital, Xi’an Jiaotong University,

Xi’an, Shaanxi, China.

Department of Hand Surgery, Honghui Hospital, Xi’an Jiaotong University, Xi’an,

Shaanxi, China.

Keywords: fibrolipomatous hamartoma; the median nerve; the index finger; surgery;

oncology.

Abstract. Fibrolipomatous hamartoma (FLH) of the nerve, also known as

lipomatosis of the nerve, neurofibrillary lipomatous lesion, or intraneural li-

poma, is a rare benign soft tissue tumor which mainly occurs in the nerves of

the upper limb, especially in the median nerve. In April 2021, a 30-year-old

male patient was secondly admitted to our hospital and underwent his third

surgery, due to the recurrence of a mass and pain in the right palm, noticeable

swelling and numbness of the right index and ring fingers, and limited flexion

and extension activities of the right ring finger. He first visited our hospital

in December 2017 due to a mass and pain in the right palm and swelling and

numbness of the right index and ring fingers. When the clinician asked for the

patient medical history, his parents stated that his right middle finger was swol-

len after birth. When the patient was ten years old; he was diagnosed with “mac-

rodactyly” at the local county hospital, not in our hospital, and subsequently,

the middle finger was amputated at the metacarpophalangeal joint level at the

local county hospital. The postoperative pathological examination was not per-

formed at that time, which was the first surgery the patient received. FLH is

clinically rare, and its exact epidemiology and etiology are poorly understood.

FLH is highly suspected in cases where a painless mass is present in the wrist,

combined with macrodactyly. Magnetic resonance imaging and pathological

examination are helpful in clarifying the diagnosis. Although FLH is a benign

tumor, an individual treatment plan is the best choice according to the severity

of the patient’s symptoms. Therefore, further exploration and understanding of

this disease by clinicians radiologists, and pathologists is necessary.

Fibrolipomatous hamartoma of the median nerve 401

Vol. 63(4): 400 - 413, 2022

Hamartoma fibrolipomatoso del nervio mediano: reporte de un

caso y revisión de la literatura.

Invest Clin 2022; 63 (4): 400 – 413

Palabras clave: hamartoma fibrolipomatoso; nervio mediano; dedo índice; cirugía;

oncología.

Resumen. El hamartoma fibrolipomatoso (FLH) del nervio, también cono-

cido como lipomatosis del nervio, lesión neurofibrilar lipomatosa, o lipointra-

neural, es un tumor benigno de tejido blando poco frecuente, que se presenta

principalmente en los nervios del miembro superior, especialmente en el nervio

mediano. En abril de 2021, un paciente masculino de 30 años fue ingresado

por segunda vez en nuestro hospital y sometido a su tercera cirugía debido a

la recurrencia de una masa y dolor en la palma derecha, evidente hinchazón y

entumecimiento de los dedos índice y anular derecho y limitadas actividades de

flexión y extensión del dedo anular derecho. En diciembre de 2017, visitó por

primera vez nuestro hospital debido a una masa y dolor en la palma derecha, y

a la hinchazón y entumecimiento de los dedos índice y anular derecho. Cuando

el clínico preguntó la historia clínica del paciente, sus padres declararon que su

dedo medio derecho estaba hinchado después del nacimiento, y cuando el pa-

ciente tenía 10 años, fue diagnosticado con “macrodactilia” en el hospital local

del condado, no en nuestro hospital Posteriormente, el dedo medio fue ampu-

tado a nivel de la articulación metacarpofalángica en el hospital comarcal local,

pero no se realizó la patología postoperatoria en ese momento, siendo ésta la

primera cirugía a la cual se sometió el paciente. La FLH es clínicamente rara,

y su epidemiología y etiología exactas no se entienden bien. En los casos que

presentan una masa indolora en la muñeca, combinada con macrodactilia, se

sospecha de FLH. La resonancia magnética y la patología son útiles para acla-

rar el diagnóstico. Aunque la FLH es un tumor benigno, el plan de tratamiento

individual es la mejor opción de acuerdo con la gravedad de los síntomas del

paciente. Por lo tanto, es necesaria una mayor exploración y comprensión de

esta enfermedad por parte de médicos, radiólogos y patólogos.

Received: 24-04-2022 Accepted: 10-05-2022

INTRODUCTION

Fibrolipomatous hamartoma of the

nerve (FLH), also known as lipomatosis of the

nerve, neurofibrillary lipomatous lesion, or

intraneural lipoma, is a rare benign soft tis-

sue tumor, which mainly occurs in the nerves

of the upper extremity, especially in the me-

dian nerve and its branches

1-3

. In addition,

a few occur in the ulnar nerve, radial nerve

or sural nerve, and a few are accompanied by

macrodactyly

. Clinically, it should be avoid-

ed to be confused with simple lipoma and

neurofibromas. Magnetic resonance imaging

(MRI) remains the gold standard for the di-

agnosis of FLH. The pathological morphology

of FLH is characterized by the proliferation

of fibrofatty tissues around the nerve, infil-

402 You-Ting et al.

Investigación Clínica 63(4): 2022

tration of the epineurium and perineurium,

and obvious thickening and deformation of

the affected nerve. As we know, there are few

reports on fibrolipomatous hamartoma of

the peripheral nerve in domestic and inter-

national literature. In this paper, we report

a rare case of fibrolipomatous hamartoma of

the median nerve and performed a literature

review on this condition.

Case presentation

This study was conducted in accordance

with the declaration of Helsinki and ap-

proved by the Ethics Committee of Honghui

Hospital, Xi’an Jiaotong University. Written

informed consent to publish the clinical de-

tails and images of the patient was obtained.

In April 2021, a 30-year-old male pa-

tient was secondly admitted to our hospital

due to the recurrence of a mass and pain in

the right palm, obvious swelling and numb-

ness of the right index finger and ring finger,

and limited flexion and extension activities

of the right ring finger.

In December 2017, he came to our

hospital for the first time because of a mass

and pain in the right palm, and swelling and

numbness of the right index figure and ring

finger. When the clinician asked about the

patient’s medical history, his parents stated

that his right middle finger was swollen after

birth, and when the patient was 10 years old,

he was diagnosed with “macrodactyly” in the

local county hospital, not in our hospital.

Subsequently, the middle finger was ampu-

tated at the metacarpophalangeal joint level

in the local county hospital, which was the

first surgery the patient received. The post-

operative pathological examination was not

performed at that time. None of the family

members had this kind of disease.

In December 2017, he underwent his

second surgery in our hospital. The preop-

erative physical examination in our hospital

showed that the right middle finger was ab-

sent. The whole right index finger was sig-

nificantly swollen and had a wide nail. The

right ring finger, proximal to the right palm

was swollen, there was a soft tissue mass of

10cm*3–5cm on the radial side of the right

palm and the palmar side of the right wrist

and a mass of 2cm*1cm on the ulnar side

of the distal segment of the right thumb

(Figs. 1A and 1B), The flexion and extension

Fig. 1. Preoperative volar side of the right hand in A and dorsal side of the right hand in B showing the absent

right middle finger, a soft tissue mass on the right palm, significantly swollen right index finger body,

and partially swollen right ring finger.

Fibrolipomatous hamartoma of the median nerve 403

Vol. 63(4): 400 - 413, 2022

activities of the right index figure and ring

finger were limited, accompanied by skin

numbness, the right hand was restricted in

making a fist, and the peripheral blood flow

was normal. The auxiliary examinations,

including B-scan ultrasonography, X films

and computerized tomography (CT), were

performed. The B-scan ultrasonography re-

vealed intense hyperechogenicity in the soft

tissue of the volar aspect of the right hand

(Fig. 2). The X films revealed the absent

right middle finger, the deformation of the

third metacarpus head with decreased bone

density, and the deformation of the articu-

lar surface of the middle phalanx head in the

index finger (Figs. 3A and 3B). The CT re-

vealed a solid lesion in the soft tissue of the

right palm (Fig. 4).

Brachial plexus nerve blocking anes-

thesia was used. An S-shaped incision was

made on the volar side of the right forearm

and the right palm. Intraoperatively, a great

amount of granular hyperplastic adipose tis-

sue was observed (Figs. 5A, 5B, 5C, and 5D).

The median nerve was dissected from the

proximal to distal, and we found the enlarge-

ment of nerve bundles, the adhesion of the

thickening epineurium, and the compres-

sion of transverse carpal ligament. We re-

moved most of the hyperplastic fatty lumps,

trimmed the epineurium, and performed

open carpal tunnel release. After the open

carpal tunnel release, the continuity of the

median nerve was intact. A Z-shaped incision

was made on the ulnar side of the right index

finger and the thumb, and the radial side of

the ring finger. The intrinsic nerves on the

ulnar side of the index finger, and the radial

side of the ring finger, had severe fatty in-

filtration distal to the proximal interphalan-

geal joint. We excised most of tumors under

the microscope, and retained some of the

nerve bundle branches and dorsal branches

of the index and ring fingers. The postopera-

tive pathological diagnosis was tumor-like

hyperplasia of adipose tissue and degenera-

tion and hyperplasia of the fibroblastic tis-

sue of nerves (Fig. 6).

After his second surgery, the patient was

hospitalized again in April 2021, due to the

recurrence of a mass and pain in the right

palm, obvious swelling and numbness of the

right index and ring fingers, and limited flex-

ion and extension activities of the right ring

finger. Physical examination upon admission

suggested that the right middle finger was

absent, and the incision of the right palm, the

thumb, the index finger, and the ring finger

healed well. There was an 8cm x 4cm irregular

soft tissue mass on the radial side of the right

palm and around the thenar eminence. The

right index finger body was obviously swollen,

with the deformation of the puffy distal pha-

lanx. Scar contracture appeared on the ulnar

side of the right ring finger, and some soft

tissue thickening (Fig. 7). Flexion and exten-

sion activities were restricted in the right in-

dex finger, accompanied by skin numbness.

In addition, the peripheral blood flow was

normal. Auxiliary examinations, including B-

scan ultrasonography, X films and magnetic

resonance imaging (MRI), were performed.

B-scan ultrasonography revealed thickening

of local soft tissues of the right index finger,

Fig. 2. Preoperative ultrasound showing dense echo

in the soft tissue of the right palm.

404 You-Ting et al.

Investigación Clínica 63(4): 2022

right ring finger, and right palm, and mul-

tiple strong echogenic and hypoechoic ar-

eas (Fig. 8). X films showed the absent right

middle finger, enlargement and deformation

of the third metacarpus head with reduced

bone density, and osteophyte deformation of

the proximal phalanx and middle phalanx of

the index finger and the proximal phalanx of

the ring finger (Figs. 9A and 9B). MRI showed

abnormal signal shadows on the volar side of

the right wrist, which suggested tumor recur-

rence, fat accumulation around the lesion

and at the distal of the third metacarpopha-

langeal joint of the right hand, hypertrophy of

the right index figure and ring finger, and the

absence of the middle finger (Fig. 10A, 10B,

and 10C).

The same S-shaped incision was made

on the right palm and the volar side of the

right forearm. Intraoperatively, an obvi-

ous adipose tissue-occupying lesion was

observed, with uneven median nerve fiber

bundles, severe fibrosis, and severe fatty and

fibrous tissue infiltration (Fig. 11A, 11B,

11C, and 11D). We performed the dissection

form the middle of the forearm to the fin-

gers of the right hand to expose the normal

range of the median nerve and the recurrent

branch of the median nerve, and then we cut

the intrinsic nerve at the proximal on the

radial and ulnar sides of the thumb. Subse-

Fig. 3. Preoperative X films of frontal position of the right hand (A) and lateral position of the right hand (B)

showing the thickened soft tissue, the absent right middle finger, deformation of the third metacarpal

head, and deformation of the articular surface of the middle phalanx of the index finger.

Fig. 4. Preoperative CT axial image of the right

hand showing a solid mass in the soft tissue

area of the right palm with hypodensity.

Fibrolipomatous hamartoma of the median nerve 405

Vol. 63(4): 400 - 413, 2022

Fig. 5. Intraoperatively, the tumor extensively infiltrated the median nerve of the right wrist, and the digital

nerves of the right index and ring finger (A and B); Postoperatively, the incision was sutured and the

peripheral blood flow was good after loosening the tourniquet (C and D).

Fig. 6. Postoperative pathology showing tumor-like proliferation of fibrous and adipose tissue and partial

degeneration of neural tissue.

Fig. 7. Preoperative soft tissue tumor of the right palm.

406 You-Ting et al.

Investigación Clínica 63(4): 2022

quently, the diseased median nerve and fat

mass were completely removed. According

to the length of the defective median nerve,

the sural nerve of 36 cm was excised from

the left calf, and folded into double strands

to do the nerve transplantation and repair

the defective median nerve. The superficial

palmar arch artery had serious adhesion to

the tumor tissue, and it ruptured during the

separation, and was repaired via microscopic

anastomosis. A Z-shape incision was made on

the volar side of the right index finger and

the radial side of the right ring finger, and

then the adipose tissues were removed again

for volume reduction. The proper digital ar-

tery on the radial side of the index finger at

the proximal ruptured, and was repaired via

microscopic anastomosis using ramus pal-

maris superficialis arteriae radialis. Postop-

eratively, the peripheral blood flow was good.

The postoperative pathological diagnosis

was tumor-like hyperplasia of fibrous fat and

neural tissue (Fig. 12).

Fig. 8. Preoperative ultrasound showing local

soft tissue thickening of the right palm

with multiple hyperechoic and hypoechoic

areas.

Fig. 9. Preoperative X films of oblique position (A) and frontal position (B) of the right hand showing soft

tissue mass thickening of the right palm, and osteophyte deformation of the proximal and middle

phalanges of the right index finger and the proximal phalanx of the ring finger.

Fibrolipomatous hamartoma of the median nerve 407

Vol. 63(4): 400 - 413, 2022

Fig. 10. For preoperative MRI, coronal T1 showing serpiginous structures-like changes (A), coronal T2

showing abnormal signal of the ring finger mass occupancy (B), and axial T2 showing coaxial cable-

like appearance (C).

Fig. 11. Intraoperatively, the fatty tissue occupation was obvious, and the thickness of median nerve fiber

bundles was uneven, with severe fibrosis as well as fatty and fibrous tissue infiltration (A and B); the

median nerve was excised for sural nerve transplantation and repairment (C and D).

Fig. 12. Postoperative pathology showing tumor-like hyperplasia of fibroadipose tissue and fibrotic degenera-

tion of neural tissue.

408 You-Ting et al.

Investigación Clínica 63(4): 2022

DISCUSSION

Definition and naming

FLH is a rare benign tumor, which main-

ly occurs in the nerves of the upper limbs. It

originates from the abnormal growth of the

fibroadipose tissue of the nerve sheath, re-

sulting in the fusiform enlargement of the

affected nerves

4,5

. The fibroid degeneration

of the compressed nerve bundles is caused

by the proliferation of adipose tissues

. The

median nerve and its branches are involved

in 85% of cases. FLH has several synonyms,

such as lipofibromatous hamartoma, lipofi-

broma, fibrofatty proliferation of the nerve,

fatty infiltration of the nerve, fibrolipoma of

the nerve, intraneural lipofibroma, neural

fibrolipoma, and macrodactylia fibrolipoma-

tosis

5,7

. In the classification of soft tissue

tumors by the World Health Organization

(WHO) in 2013, fibrolipomatous hamartoma

of the nerve, fatty infiltration, and neural fi-

brolipoma are all classified as lipomatosis of

the nerve

, which is different from intraneu-

ral lipoma in the clinical manifestations and

treatment

. Due to the confusion of naming

and the rarity of this disease, its diagnosis

and treatment are complicated. The proper

terminology for this lesion has been incon-

sistent in the literature and it is currently

recommended that the most accurate term

for this lesion is “fibrolipoma”

, which best

reflects the hamartomatous nature of this

lesion. We also prefer the term “fibrolipoma-

tous hamartoma of the nerve”.

Epidemiology

This lesion was firstly reported by Ma-

son in 1953

. In 1969, Johnson and Bon-

figilio firstly called this lesion as lipofibro-

matous hamartoma

. In 1994, Guthikonda

et al. proposed a new classification for neu-

ral lipomatous tumours: (a) soft lipoma,

(b) intraneural lipoma, (c) lipofibromatous

hamartoma, and (d) macrodystrophia lipo-

matosa

. FLH commonly occurred in those

under 30 years old

. This lesion in infants,

children, and young adults was manifest-

ed by either no symptoms or compressive

neuropathy

. In many cases, the mass has

existed for many years before the onset of

symptoms

. The incidence of the FLH with

macrodactyly in women is twice as much as

in men. The incidence of the FLH without

macrodactyly in women is the same than in

men, and the incidence of the FLH in the

upper limbs is higher than that of the lower

limbs

14-16

. In our reported case, the FLH oc-

curred in a young man, involving unilateral

median nerve and its branches, accompa-

nied by macrodactyly.

Etiology and Pathogenesis

Although some potential etiologies

have been described, the cause of this ab-

normal growth of the nerve is still unknown,

which is possibly due to the proliferation

and hypertrophy of fibroblasts and mature

adipocytes in the epineurium

. A consid-

erable number of cases occur at birth or in

childhood. Many scholars believe that it may

be a congenital disease caused by the abnor-

mal development of the flexor retinaculum

or transverse carpal ligament, especially in

the carpal tunnel area or with macrodactyly.

There are also cases with an overgrowth of

bone tissue and skin soft tissue

12,18

. Some

scholars believe that FLH is acquired and

caused by reactions such as trauma or long-

term chronic irritation

4.9

. The true etiology

might be the combination of congenital fac-

tors and acquired and reactive factors, which

stimulate the formation of the tumor

. Our

reported case who had no history of trauma,

presented with macrodactyly at birth, and

his tumor recurred and continued to prolif-

erate after two surgeries.

Although FLH is hyperproliferative, its

behavior resembles that of a benign tumor,

with no evidence of malignancy in confirmed

cases and no familial cases. The FLH subtype

has been reported to be associated with mu-

tations in the PIK3CA pathway

, similar to

other hyperproliferative disorders. Neurore-

gional macrodactyly is a common comorbid-

ity, and 20–66% of FLH cases experienced

Fibrolipomatous hamartoma of the median nerve 409

Vol. 63(4): 400 - 413, 2022

this macrodactyly

14,15,21

. The exact relation-

ship between the two remains elusive.

Clinical Manifestations

Typical FLH cases mainly occur in the

first three decades of life, mostly at birth or

in early childhood. Locally, gradually enlarg-

ing painless masses are the main symptom.

90% of cases are unilateral

12,22

. The course

of the disease is variable, and the affected

finger is symmetrically or asymmetrically

thickened, which is often accompanied by

dyskinesia. This kind of tumor mainly occurs

in the upper limb, and the median nerve and

its branches are the most commonly affect-

ed nerves, especially the median nerves at

the distal end of the forearm and on the vo-

lar side of the wrist

. Pain, numbness, sen-

sory abnormalities, and nerve entrapment

syndrome usually occur in the late stage of

this disease

. Approximately one-third of

cases are accompanied with macrodactyly,

which is commonly seen in the phalanges.

However, there was a case report describing

an elderly patient with macrodactyly in the

metacarpal bone

. The case we reported

presented with macrodactyly of the middle

finger at birth. Unfortunately, because the

clinicians in the local county hospital at that

time had a lack of understanding of this dis-

ease, they performed the middle finger am-

putation to relieve pain and numbness of the

patient.

Imaging Examinations

(1) B-scan ultrasonography suggests

a dense-echo mass in the hypoechoic area.

Nerve bundles are in the hypoechoic area,

and adipose tissues are in the hyperechoic

area. Color Doppler shows no blood flow sig-

nal

(2) X-ray films show thickened soft tis-

sues, and examine the bone for hypertrophy,

hyperplasia, and other deformities

(3) MRI is the gold standard for the

diagnosis of this disease

24, 25

, which is help-

ful for the differentiation and preoperative

evaluation. Fat with high-signal intensity is

showed on T1- and T2-weighted images. In

the T1-weighted axial images, there is typi-

cal fat with high-signal intensity and nerves

with a low-signal intensity and co-axial ca-

ble-like appearance. Coronal images showed

serpiginous structures, and thickened nerve

bundles were wrapped by adipose tissues,

separated from each other, and evenly dis-

tributed in the nerve sheath. Fat in the T1-

weighted images showed high-signal inten-

sity, while fat in the T2-weighted images with

fat suppression showed low-signal intensity.

Fat was asymmetrically distributed, and sag-

ittal images showed a spaghetti-like appear-

ance. These specific features of MRI can be

used as diagnostic criteria, even without a

pathological biopsy

3,14

. For the case we re-

ported, the preoperative MRI showed typical

coaxial cable-like appearance and spaghetti-

like serpiginous structures, which was very

helpful for early diagnosis.

(4) Electromyography and nerve con-

duction examination are helpful to diagnose

nerve compression lesions

Pathological Examination

(1) General observation shows this

kind of tumor is irregularly fusiform, its

color is yellow or yellowish-brown, and the

affected nerves may be elongated, thickened

and uneven in thickness, which is caused by

the excessive proliferation of mature adipo-

cytes and fibrous tissue

19,25

(2) Histological morphology shows

excessive proliferation of the adventitial

fibroadipose tissues of the affected nerves

and extensive infiltration of the nerve

bundles, and the adventitial fibroadipose

tissues wraps, separates, and compresses

these nerve bundles. In cases with a long

course of disease, degenerative and atro-

phic changes of nerve tissues may occur. Fi-

brous tissues and perineurial cells located

around the nerve bundle are arranged in

concentric circles.

12,26

Unlike lipomas, the

FLH presents infiltrative growth and fat is

asymmetrically distributed between nerve

bundles

12,26

In the proliferative fibrous fat

410 You-Ting et al.

Investigación Clínica 63(4): 2022

tissue, the hyperplasia of medium and small

blood vessels and lymphatics occurs focal-

ly, and hemangioma or lymphangioma-like

changes may appear in some areas. In ad-

dition to the above-mentioned typical mor-

phology, bone metaplasia may also occur in

a few cases. Immunohistochemical markers

have no special significance for the diagno-

sis of this disease, with being positive for

CD34, S100, and vimentin and negative for

epithelial membrane antigens, desmin, and

glial fibrillary acidic protein antibodies

Differential diagnosis

Clinically, many lesions need to be dif-

ferentiated from FLH, such as neurofibroma,

neurilemoma, neuroma, ganglion, lipoma,

vascular malformation, intraneural neuro-

ectodermal tumor, intraneural lipoma, and

traumatic neuroma

6,18

Treatment

Although FLH is a benign tumor, due

to the rarity of this disease and the lack of

randomized controlled studies, it is difficult

to determine the best treatment for it. So

far, the surgical approach of FLH has been

controversial.

(1) Conservative treatment is an option

for asymptomatic individuals

16,27

, for whom

there are no neurological symptoms such

as pain, numbness or sensory abnormali-

ties, and if the tumor is small enough not

to affect the function and aesthetic of the

affected limb. There is no evidence of malig-

nancy. It primarily requires observation or a

pathological biopsy

(2) Carpal tunnel release is recommend-

ed to those with symptoms of median nerve

compression, including traditional incision

release, microscopic or arthroscopic carpal

tunnel release, and epineurium incision and

intraneural release as appropriate

. Nerve

decompression can reduce pain, numbness

and the risk of the sequelae of sensorimo-

tor disorders

. It can also shrink the mass

and improve thumb-to-palm strength

16,27

. If

there are no characteristic imaging findings,

a surgical exploration and an excisional bi-

opsy are required to clarify the diagnosis.

(3) Microscopic resection is recom-

mended if the tumor is large, and vascular

injury and fibrosis further aggravate the

nerve damage

13,16

. For cases of continu-

ous and progressive deterioration of neuro-

logical symptoms, in order to maximize the

preservation of nerve function, when the tu-

mor resection was performed, interfascicu-

lar tumor dissection was performed together

under a microscope. However, the dissection

may cause segmental nerve ischemia

12,16,28

Therefore, the specific indications for this

technique are still controversial.

(4) Tumor and volume reduction, es-

pecially for cases combined with macrodac-

tyly or swollen/deformed fingers, is recom-

mended. In order to improve the appearance

of the affected finger while preserving nerve

function, tumor reduction surgery can be

selected for soft tissue reduction, and if nec-

essary, epiphyseal block, osteotomy correc-

tion, or the removal of the affected finger

nerve was performed

26,28

. For some elderly

patients, finger or limb amputation can be

considered

(5) The radical resection of the tumor

is only performed in the cases of neurodis-

abling damage. Some scholars believe that

this may lead to intolerable sensorimotor

defects

7,12,28

. If the tumor involves the bra-

chial plexus nerve, it is difficult to complete-

ly remove the tumor

. Postoperative fibro-

sis caused by fiber healing can significantly

interfere with the nerve conduction

15,28

, so

that motor and sensory loss in the innervat-

ed area may occur. The improvement of mo-

tor functions requires tendonoplasty repair,

and although nerve grafting is an option for

sensory restoration, there is still no satisfac-

tory solution.

For this case we report, when the pa-

tient firstly came to our hospital for sur-

gery, a large number of proliferating fibers

and fatty tumor tissues surrounding the

nerve bundles were observed during opera-

tion. It was very challenging to completely

Fibrolipomatous hamartoma of the median nerve 411

Vol. 63(4): 400 - 413, 2022

remove the tumor. Therefore, we decided to

remove most of the tumor tissue to reduce

its size, and loosen the carpal tunnel, while

the median nerve and the finger nerves were

preserved, which significantly reduced the

patient’s symptoms and improved the ap-

pearance of the affected finger. Three years

after this operation, the tumor recurred and

the patient was admitted again to our hos-

pital for surgery. Due to extensive adhesion

of the tumor tissue and the median neuro-

fibrillary degeneration, the tumor and the

median nerve of the diseased segment were

removed, and then the sural nerve was cut to

do the nerve grafting and repair. After this

operation, the symptoms of the patient were

relieved, and the feelings and activities of

the palms and fingers were restored to the

greatest extent.

CONCLUSION

The FLH is clinically rare, and its exact

epidemiology and etiology are not well un-

derstood. In cases of a painless mass in the

wrist, combined with macrodactyly, FLH is

highly suspected. Magnetic resonance imag-

ing and pathological examination are helpful

to clarify the diagnosis. Although FLH is a

benign tumor, the individual treatment plan

is the best choice according to the severity

of the patient’s symptoms. Therefore, clini-

cians, radiologists, and pathologists need to

further explore and understand this disease.

Funding

This research received no specific grant

from any funding agency in the public, com-

mercial, or not-for-profit sectors.

Ethics approval and consent to participate

This study was conducted in accordance

with the declaration of Helsinki. This study

was conducted with approval from the Ethic

committee of Honghui Hospital, Xi’an Jiao-

tong University.

Consent for publication

Written informed consent to publish

the clinical details and images of the patient

was obtained.

Conflict of interests

All authors declare they have no con-

flict of interests.

Authors ORCID Numbers

• Y-Ting Dang (Y-T D):

0000-0001-8486-3839

• Qiang Wang (QW):

0000-0002-4458-4912

• Yun-Ping Zhou(Y-P Z):

0000-0002-7399-1269

• Deng-Ke Wei (D-K W):

0000-0002-4534-6801

• Fei Xie (FX) https:

0000-0002-7984-1093

Contributions Authors’

Y-T D, FX, Substantial contributions to

the conception and design of the work.

YT D, QW, Y-P Z, D-KW, X-H O, FX, the

acquisition, analysis, and interpretation of

data for the work.

Y-T D, drafting the work.

Y-T D, QW, Y-P Z, D-K W, X-H O, F X, re-

vising it critically for important intellectual

content.

Y-T D, QW, Y-P Z, D-K W, X-H O, F X, final

approval of the version to be published and

agreement to be accountable for all aspects

of the work in ensuring that questions rela-

ted to the accuracy or integrity of any part of

the work are appropriately investigated and

resolved.

412 You-Ting et al.

Investigación Clínica 63(4): 2022

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