June 25, 2013
9:36:10am
WSPC/135-HS
FA1
1372018
Hand Surgery, Vol. 18, No. 2 (2013) 267272 © World Scientific Publishing Company DOI: 10.1142/S0218810413720180
BILATERAL MACRODYSTROPHIA LIPOMATOSA WITH SYNDACTYLY: A CASE REPORT AND LITERATURE REVIEW
Hand Surg. 2013.18:267-272. Downloaded from www.worldscientific.com by FLINDERS UNIVERSITY LIBRARY on 02/10/15. For personal use only.
Steven B. Albright, Erik M. Wolfswinkel, Kevin J. Caceres, William M. Weathers and Larry H. Hollier Jr. Division of Plastic Surgery Michael E. Debakey Department of Surgery Baylor College of Medicine, Houston, TX 77030, USA Received 27 December 2012; Revised 22 February 2013; Accepted 25 February 2013 ABSTRACT Macrodystrophia lipomatosa is a rare, non-hereditary form of congenital local gigantism characterised by enlargement and hypertrophy of all mesenchymal tissue components with a disproportionate increase in adipose tissue. This form of macrodactyly has been reported in association with other anomalies including polydactyly, brachydactyly, syndactyly, and symphalangism. We describe a previously unreported case of bilateral upper extremity macrodystrophia lipomatosa with syndactyly in a 23-month-old boy. In this report, we emphasise the importance of establishing a diagnosis with imaging and review the described surgical approaches to treating this difficult condition. Keywords: Macrodystrophia Lipomatosa; Macrodactyly; Syndactyly.
INTRODUCTION
extremely rare.1,7 MDL has been reported in association with other anomalies including polydactyly, brachydactyly, syndactyly, and symphalangism. Here, we describe a previously unreported case of bilateral upper extremity macrodystrophia lipomatosa with syndactyly.
Macrodystrophia lipomatosa (MDL) is a rare, non-hereditary form of congenital local gigantism characterized by enlargement and hypertrophy of all mesenchymal tissue components with a disproportionate increase in adipose tissue.13 As a true progressive form of macrodactyly, affected parts grow disproportionately to the rest of the body,4,5 with disproportionate bone growth usually ceasing after puberty following physeal closure.1,4,6 MDL most often occurs in the lower extremity and involves multiple adjacent digits.1 It usually exhibits unilateral involvement with distribution along a defined sclerotome, such as that of the median nerve in the upper extremity or the plantar nerve in the lower extremity.1 Bilateral involvement is
CASE REPORT A 23-month-old boy presented to the Hand Clinic at Texas Children’s Hospital for evaluation of bilateral macrodactyly and syndactyly of multiple digits. According to the parents, the patient had these hand deformities since birth and they progressively became more pronounced. He was otherwise healthy
Correspondence to: Dr. Larry H. Hollier, Jr., Division of Plastic Surgery, Michael E. Debakey Department of Surgery, Baylor College of Medicine, 6701 Fannin St. Suite 610, Houston, TX 77030, USA. Tel: (þ1) 832-799-3049, Fax: (þ1) 832-825-3192, E-mail: [email protected] 267
June 25, 2013
9:36:10am
Hand Surg. 2013.18:267-272. Downloaded from www.worldscientific.com by FLINDERS UNIVERSITY LIBRARY on 02/10/15. For personal use only.
268
WSPC/135-HS
FA1
1372018
S. B. Albright et al.
Fig. 1 Bilateral mitten hand deformities with asymmetric macrodactyly and syndactyly involving multiple adjacent digits.
without significant medical problems or other congenital defects. There was no family history of hand deformities. Prior to presentation, he had been meeting all developmental milestones, but his prominent digits began to restrict his ability to perform age-appropriate activities. His mother reported he had difficulty while turning pages in a book, and grasping crayons or markers. Physical examination revealed complete syndactyly of the right middle and ring fingers with significant soft tissue overgrowth (Fig. 1). The right index finger was divergent and hypertrophic. Range-of-motion appeared limited at the involved MCP joints. The right thumb and small finger were normal in
(A)
appearance and functionally intact. The left hand also showed complete syndactyly of the second through fourth digits with marked overgrowth. Full flexion was intact and concerted in the syndactylous digits. The thumb and small finger were separate with normal proportional phalanges and preserved functionality. Limited grasping and modified pinch were observed in both hands. Radiographs of his hands demonstrated marked hypertrophy of the phalanges and soft tissues of the index, middle and ring fingers with soft tissue syndactyly and distal bony synostosis (Fig. 2). Right hand films showed enlargement of the third and, to a lesser extent, the second metacarpal. The right
(B)
(C)
Fig. 2 Anteroposterior views of the right (A) and left (B) hands demonstrate complete syndactyly with partial synostosis of the distal phalanges. Divergent angulation of the right second and third digits is also evident. Lateral view (C) reveals dorsal deviation from overgrowth of the volar soft tissues.
June 25, 2013
9:36:12am
WSPC/135-HS
FA1
1372018
Macrodystrophia Lipomatosa with Syndactyly
(A)
(B)
269
(C)
Hand Surg. 2013.18:267-272. Downloaded from www.worldscientific.com by FLINDERS UNIVERSITY LIBRARY on 02/10/15. For personal use only.
Fig. 3 MR imaging in macrodystrophia lipomatosa. T1-weighted coronal images of the right (A) and left (B) hands reveal phalangeal hypertrophy and fatty infiltration of the intrinsic hand musculature. Axial image (C) shows diffuse high signal intensity with thin hypointense bands characteristic of fibroadipose proliferation.
index finger deviated radially and dorsally whereas the middle and ring fingers were ulnarly inclined. Magnetic resonance imaging (MRI) studies including gadolinium-enhanced, T1-weighted axial sequences of the bilateral hands and wrists were obtained (Fig. 3). These confirmed bilateral macrodystrophia lipomatosa with associated fibrolipomatous hamartomas of the median nerves and concurrent syndactyly. The median nerves were noted to be markedly hypertrophic just proximal to the carpal tunnel (Fig. 4). The case was discussed extensively with the family regarding surgical options and outcomes. It was emphasised that, given the complexity of his condition, any attempt at surgical correction would require several staged procedures. Treatment would aim to reduce the digit while maintaining useful motion.
Fig. 4 The median nerves were noted to be markedly hypertrophic just proximal to the carpal ligament. Neural enlargement is a sign characteristic of macrodystrophia lipomatosa. The arrows point to the split fascicles of the hypertrophic right median nerve shown on axial MRI.
Repetitive debulking and syndactyly release surgeries would be required. Amputation of some or all of the involved digits was also discussed as an option. Careful counseling was provided, reinforcing that given the extent of the defects, it was unlikely that surgery would lead to a good functional or cosmetic outcome. The family decided to forego any surgical intervention. Yearly following-up is ongoing.
DISCUSSION Macrodystrophia lipomatosa is a non-hereditary congenital anomaly characterized by enlargement and hypertrophy of all mesenchymal elements including phalanges, tendons, nerves and vessels.13 Overgrowth occurs in a specific sclerotome region. The lower limb is more often involved than the upper limb, and in most cases multiple adjacent digits are affected, with the 2nd and 3rd digits being the most common.3 MDL usually presents unilaterally but is sometimes seen with bilateral limb involvement and can be complicated by syndactyly or polydactyly.1,6,8 The differential diagnosis of MDL can be seen in Table 1. Although most patients are initially asymptomatic, digital overgrowth can lead to interference with joint function, degenerative joint disease or cause neurovascular compression and entrapment.9,10 Patients most frequently present for evaluation for cosmetic reasons. Various surgical techniques have been described to treat macrodactyly caused by MDL. These have yielded some success, but inadequate correction and high recurrence rates continue to plague surgical outcomes. We report an unusual presentation of bilateral hand macrodactyly in a 23-month-old boy with associated anomalies including MDL, fibrolipomatous harmartoma (FLH),
June 25, 2013
9:36:16am
270
WSPC/135-HS
S. B. Albright et al.
Table 1 Diagnosis
Hand Surg. 2013.18:267-272. Downloaded from www.worldscientific.com by FLINDERS UNIVERSITY LIBRARY on 02/10/15. For personal use only.
FA1
1372018
Macrodactyly Differential Diagnosis and MRI Imaging Characteristics. Characteristics
Imaging
Neurofibromatosis (NF) type I
family history cafe-au-lait spots soft tissue nodules
T2W: marked hyperintensity adjacent to nerves. thinned bone shafts are present.
Hemangiomatosis
haemangiomas audible bruits
T2W: septate high-signal-intensity channels corresponding to the vascular channels and fibrous strands in haemangiomas.
Lymphangiomatosis
diffuse swelling pitting odema
T1W: hyperintense to muscle T2W: hyperintense to fat
Klippel-Trenaunay-Weber Syndrome
typical cutaneous capillary haemangiomas varicose veins
T2W: high-signal-intensity malformed venous and lymphatic lesions
Proteus Syndrome
T1W: diffuse high-signal-intensity characteristic of widespread fatty tissue.
Fibrolipomatous Hamartoma
tumour-like lipomatous process fatty tissue interspersed among nerve bundles endoneurial and perineurial fibrosis
MRI: speckled appearance as mature fat infiltrates the neural sheath
Macrodystrophia Lipomatosa
bony overgrowth fat deposition in subcutaneous tissues, tendons, muscles and nerves
MRI: fatty tissue appearance with enlargement of the mesenchymal tissues, bony enlargement, hypertrophy along a nerve territory, unilaterality, and demonstration of fat within the nerve sheath,
skull abnormalities pigmented nevi lung cysts intra-abdominal lipomas
complete syndactyly and partial synostosis of the affected distal phalanges. The most prominent pathologic finding in MDL is diffuse adipose infiltration of a fine meshwork of fibrous tissue that involves bone marrow, periosteum, muscles nerve sheaths and subcutaneous tissues.1 Phalanges are often elongated and broadened and the periosteum can be studded with small nodules consisting of chondroblasts, osteoblasts and osteoclasts. The nodules usually become larger and more numerous distally causing the terminal phalanges to sometimes have a characteristic mushroom-like appearance.11 The trabecular structure of affected phalanges generally remains well-preserved.8 Vessels of the affected digit are often proportionately enlarged without arteriovenous fistula or increased vascularity. Neural enlargement and irregularity is common and caused by perineural and endoneural fibrosis without an increase in number of axons. Commonly, MDL is associated with FLH, as seen in our patient. In FLH the deposition of fat is within the nerve sheath, while in MDL it occurs throughout the digit or extremity. MDL and FLH are associated in approximately 30% of
cases.9 Imaging is vital in establishing a diagnosis. MRI is considered by many the imaging modality of choice for evaluating MDL.9,10 MRI can be used for definitive diagnosis of MDL, as the fatty tissue appearance with enlargement of the mesenchymal tissues is characteristic for MDL. MRI easily demonstrates excess fibro-fatty tissue with fibrous strands present on T1-weighted imaging as linear strands of low-intensity signal.9,12 Radiologic investigations afford a noninvasive way to make a definitive diagnosis, differentiating MDL from other causes of localised hypertrophy and their respective prognoses, complications, and treatments (Table 1).9 Although the getiology of macrodystrophia lipomatosa has yet to be discovered, there have been many hypotheses proposed such as lipomatous degeneration,6 disturbed foetal circulation,13 erroneous segmentation,9 trophic influence of a tumified nerve,6 and the in utero disturbance of a growth-limiting factor during limb bud development.1 Recent literature has also suggested involvement of the PTEN gene (phosphatase and tensin homologue deleted on chromosome 10) which is primarily a tumour suppressor gene that significantly influences
June 25, 2013
9:36:16am
WSPC/135-HS
1372018
FA1
Hand Surg. 2013.18:267-272. Downloaded from www.worldscientific.com by FLINDERS UNIVERSITY LIBRARY on 02/10/15. For personal use only.
Macrodystrophia Lipomatosa with Syndactyly
cell and tissue growth.1,14 The possible involvement of PTEN in the etiology of MDL may suggest that MDL is a localised form of Proteus syndrome.1,14 PTEN gene involvement may explain the marked increase in adipose tissue, but further research is needed to prove the role of PTEN in MDL and its mechanism in disproportionate lipomatous formation.1,14 MDL generally comes to clinical attention due to cosmetic reasons. Parental concern for social acceptance is a strong motivator for parents to seek surgical treatment for a child at a young age. Obvious mechanical problems can also lead to early clinic presentation. Fibroadipose enlargement predominantly affects the volar aspect and distal portions of the digit, often resulting in dorsal deviation.15 This upward curvature of the digits causes difficulty with ambulation or hand function. Articular surfaces in the affected digit may also be slanted, further inhibiting function.8 In more severe cases, tissue bulk alone can restrict motion enough to significantly hinder function, as seen in our patient.16 Later presentations can include entrapment neuropathy and secondary osteoarthritis with formation of subchondral cysts and large osteophytes.9,11,16 It has been suggested that all MDL patients be tested with electrophysiologic studies in all limbs, even those unaffected, in order to assess for possible neuropathies.17 Surgical intervention should be based on the intent of correcting cosmetic appearance and improving mechanical function, while weighing the risks of possible complications or recurrence. The incidence of nerve injury following extensive debulking is approximately 3050% and the recurrence rate of excessive growth is at least 3360%.1,11 Various surgical approaches to treating macrodactyly have demonstrated inconsistent outcomes. Surgical interventions include digit reduction procedures (debulking, defatting, phalangectomy, arthrodesis and/or wedge osteotomies9,11,1719), growth limiting procedures (epiphysiodesis19), and ray amputations.18 Procedures aimed at digital reduction are most effective in less severe cases and for those patients who still retain some function. The most common methods use some combination of the described methods above. Due to poor vascularity relative to the overall mass of hypertrophic tissue and high rates of recurrence, staged surgeries are typically required. This allows time for revascularisation between successive debulking procedures.16 If epiphysiodesis is performed careful measurement and comparison to unaffected digits of the same sex parent must be made and the procedure timed accordingly in order to establish correct digit length.19 When central ray amputation is
271
performed, aesthetic appearance may be improved with adjacent digit transposition. The extent and type of surgical treatment should be based on the patient’s age, digital involvement, degree of motion, and severity of disease. In more complicated cases, efforts to reduce digit size while maintaining useful motion are pursued, but additional surgical considerations need to addressed. Grossly enlarged digits require staged surgeries for sequential debulking of each side of the digit.19 Several features influence the appearance of the digits besides the overall dimensions.19 Specifically, bulbous fingertips, angulation deformities, and associated anomalies, including polydactyly, brachydactyly, syndactyly, and symphalangism, need to be managed accordingly. Specific approaches include closing wedge osteotomies for angulation deformities, amputation for polydactyly, and syndactyly release. Multiple procedures are generally required and poor outcomes are expected.19 In these complicated situations, thorough patient and family counselling must be provided regarding the alternatives, risks, and realistic expectations for attempts at digitpreserving surgery. Given the progressive and diffuse nature of MDL, complete correction to normalcy is not always possible.20 Multiple procedures may be performed and still result in a deformed digit with limited function. Recurrence and further functional deterioration with continued growth often lead to subsequent amputation to improve hand function.20 When the macrodactylous digits are grossly deforming and nonfunctional, early ray amputation should be offered as definitive treatment. With pervasive bilateral upper extremity involvement, as in our patient’s condition, it is difficult to recommend amputation of multiple digits or to commit the patient to innumerable salvage procedures when the outcome is expected to be very poor. Extensive counselling and guidance for the parents become paramount when there are no good options to offer. In summary, we describe a previously unreported case of bilateral upper extremity macrodystrophia lipomatosa with syndactyly. We emphasised the importance of establishing a diagnosis with imaging and reviewed the described surgical approaches to treating this difficult condition. Severe forms of macrodactyly present unique problems with regard to patient management. When MDL involves multiple digits or extremities, it may be difficult to decide between amputations versus digit-preserving treatment plans. Informed decision-making after appropriate delivery of prognostic information and counselling will ultimately determine the best course of action.
June 25, 2013
9:36:17am
272
WSPC/135-HS
1372018
S. B. Albright et al.
References
Hand Surg. 2013.18:267-272. Downloaded from www.worldscientific.com by FLINDERS UNIVERSITY LIBRARY on 02/10/15. For personal use only.
FA1
1. Rohilla S et al., Macrodystrophia lipomatosa involving multiple nerves, J Orthop Trauma 13(1):4145, 2012. 2. Feriz H, Makrodystrophia lipomatosa progressiva, Virchows Archiv Pathol Anat Physiol Klin Med 260(2):308368, 1926. 3. Barsky AJ, Macrodactyly, J Bone Joint Surg Am 49(7):12551266, 1967. 4. Linder JM et al., Congenital anomalies of the hand: an overview, J Craniofac Surg 20(4):9991004, 2009. 5. Van Heest AE, Congenital disorders of the hand and upper extremity, Pediatr Clin North Am 43(5):11131133, 1996. 6. Kozin SH, Upper-extremity congenital anomalies, J Bone Joint Surg 85(8):15641576, 2003. 7. Stern PJ, Nyquist SR, Macrodactyly in ulnar nerve distribution associated with cubital tunnel syndrome, J Hand Surg Am 7(6):569571, 1982. 8. Gupta SK, et al., Macrodystrophia lipomatosa: radiographic observations, Br J Radiol 65(777):769773, 1992. 9. Singla V et al., Case report: Macrodystrophia lipomatosa — illustration of two cases, Indian J Radiol Imaging 18(4):298301, 2008. 10. Soler R et al., MR findings of macrodystrophia lipomatosa, Clin Imaging 21(2):135137, 1997. 11. Khan RA et al., Macrodystrophia lipomatosa: four case reports. Ital J Pediatr 36:69, 2010.
12. Koplay M, Kantarci M, Kilinc G, Macrodystrophia lipomatosa: multidetector CT and MRI findings, New Zealand Med J 125:1352, 2012. 13. Swanson AB, Barsky AJ, Entin MA, Classification of limb malformations on the basis of embryological failures, Surg Clin North Am 48(5):11691179, 1968. 14. Goberdhan DC, Wilson C, PTEN: tumour suppressor, multifunctional growth regulator and more, Hum Mol Genet 2:19, 2003. 15. D’Costa H et al., Magnetic resonance imaging in macromelia and macrodactyly, Br J Radiol 69(822):502507, 1996. 16. Watt AJ, Chung KC, Macrodystrophia lipomatosa: a reconstructive approach to gigantism of the foot, J Foot Ankle Surg 43(1):5155, 2004. 17. Kozanoglu E, Koc F, Goncu KI, Macrodystrophia lipomatosa with multiple entrapment neuropathies: a case report, Int J Neurosci 118 (4):545553, 2008. 18. Bulut M et al., Ray amputation for the treatment of macrodactyly in the foot: report of three cases, Acta Orthop Traumatol Turc 45(6):458462, 2011. 19. Akinci M, Ay S, Ercetin Ö, Surgical treatment of macrodactyly in older children and adults, J Hand Surg 29(6):10101019, 2004. 20. McCombe M, Kay SP, Macrodatyly, in Wolfe SW (ed.), Green’s Operative Hand Surgery, Elsevier, Philadelphia, pp. 14371444, 2005.
9:36:10am
WSPC/135-HS
FA1
1372018
Hand Surgery, Vol. 18, No. 2 (2013) 267272 © World Scientific Publishing Company DOI: 10.1142/S0218810413720180
BILATERAL MACRODYSTROPHIA LIPOMATOSA WITH SYNDACTYLY: A CASE REPORT AND LITERATURE REVIEW
Hand Surg. 2013.18:267-272. Downloaded from www.worldscientific.com by FLINDERS UNIVERSITY LIBRARY on 02/10/15. For personal use only.
Steven B. Albright, Erik M. Wolfswinkel, Kevin J. Caceres, William M. Weathers and Larry H. Hollier Jr. Division of Plastic Surgery Michael E. Debakey Department of Surgery Baylor College of Medicine, Houston, TX 77030, USA Received 27 December 2012; Revised 22 February 2013; Accepted 25 February 2013 ABSTRACT Macrodystrophia lipomatosa is a rare, non-hereditary form of congenital local gigantism characterised by enlargement and hypertrophy of all mesenchymal tissue components with a disproportionate increase in adipose tissue. This form of macrodactyly has been reported in association with other anomalies including polydactyly, brachydactyly, syndactyly, and symphalangism. We describe a previously unreported case of bilateral upper extremity macrodystrophia lipomatosa with syndactyly in a 23-month-old boy. In this report, we emphasise the importance of establishing a diagnosis with imaging and review the described surgical approaches to treating this difficult condition. Keywords: Macrodystrophia Lipomatosa; Macrodactyly; Syndactyly.
INTRODUCTION
extremely rare.1,7 MDL has been reported in association with other anomalies including polydactyly, brachydactyly, syndactyly, and symphalangism. Here, we describe a previously unreported case of bilateral upper extremity macrodystrophia lipomatosa with syndactyly.
Macrodystrophia lipomatosa (MDL) is a rare, non-hereditary form of congenital local gigantism characterized by enlargement and hypertrophy of all mesenchymal tissue components with a disproportionate increase in adipose tissue.13 As a true progressive form of macrodactyly, affected parts grow disproportionately to the rest of the body,4,5 with disproportionate bone growth usually ceasing after puberty following physeal closure.1,4,6 MDL most often occurs in the lower extremity and involves multiple adjacent digits.1 It usually exhibits unilateral involvement with distribution along a defined sclerotome, such as that of the median nerve in the upper extremity or the plantar nerve in the lower extremity.1 Bilateral involvement is
CASE REPORT A 23-month-old boy presented to the Hand Clinic at Texas Children’s Hospital for evaluation of bilateral macrodactyly and syndactyly of multiple digits. According to the parents, the patient had these hand deformities since birth and they progressively became more pronounced. He was otherwise healthy
Correspondence to: Dr. Larry H. Hollier, Jr., Division of Plastic Surgery, Michael E. Debakey Department of Surgery, Baylor College of Medicine, 6701 Fannin St. Suite 610, Houston, TX 77030, USA. Tel: (þ1) 832-799-3049, Fax: (þ1) 832-825-3192, E-mail: [email protected] 267
June 25, 2013
9:36:10am
Hand Surg. 2013.18:267-272. Downloaded from www.worldscientific.com by FLINDERS UNIVERSITY LIBRARY on 02/10/15. For personal use only.
268
WSPC/135-HS
FA1
1372018
S. B. Albright et al.
Fig. 1 Bilateral mitten hand deformities with asymmetric macrodactyly and syndactyly involving multiple adjacent digits.
without significant medical problems or other congenital defects. There was no family history of hand deformities. Prior to presentation, he had been meeting all developmental milestones, but his prominent digits began to restrict his ability to perform age-appropriate activities. His mother reported he had difficulty while turning pages in a book, and grasping crayons or markers. Physical examination revealed complete syndactyly of the right middle and ring fingers with significant soft tissue overgrowth (Fig. 1). The right index finger was divergent and hypertrophic. Range-of-motion appeared limited at the involved MCP joints. The right thumb and small finger were normal in
(A)
appearance and functionally intact. The left hand also showed complete syndactyly of the second through fourth digits with marked overgrowth. Full flexion was intact and concerted in the syndactylous digits. The thumb and small finger were separate with normal proportional phalanges and preserved functionality. Limited grasping and modified pinch were observed in both hands. Radiographs of his hands demonstrated marked hypertrophy of the phalanges and soft tissues of the index, middle and ring fingers with soft tissue syndactyly and distal bony synostosis (Fig. 2). Right hand films showed enlargement of the third and, to a lesser extent, the second metacarpal. The right
(B)
(C)
Fig. 2 Anteroposterior views of the right (A) and left (B) hands demonstrate complete syndactyly with partial synostosis of the distal phalanges. Divergent angulation of the right second and third digits is also evident. Lateral view (C) reveals dorsal deviation from overgrowth of the volar soft tissues.
June 25, 2013
9:36:12am
WSPC/135-HS
FA1
1372018
Macrodystrophia Lipomatosa with Syndactyly
(A)
(B)
269
(C)
Hand Surg. 2013.18:267-272. Downloaded from www.worldscientific.com by FLINDERS UNIVERSITY LIBRARY on 02/10/15. For personal use only.
Fig. 3 MR imaging in macrodystrophia lipomatosa. T1-weighted coronal images of the right (A) and left (B) hands reveal phalangeal hypertrophy and fatty infiltration of the intrinsic hand musculature. Axial image (C) shows diffuse high signal intensity with thin hypointense bands characteristic of fibroadipose proliferation.
index finger deviated radially and dorsally whereas the middle and ring fingers were ulnarly inclined. Magnetic resonance imaging (MRI) studies including gadolinium-enhanced, T1-weighted axial sequences of the bilateral hands and wrists were obtained (Fig. 3). These confirmed bilateral macrodystrophia lipomatosa with associated fibrolipomatous hamartomas of the median nerves and concurrent syndactyly. The median nerves were noted to be markedly hypertrophic just proximal to the carpal tunnel (Fig. 4). The case was discussed extensively with the family regarding surgical options and outcomes. It was emphasised that, given the complexity of his condition, any attempt at surgical correction would require several staged procedures. Treatment would aim to reduce the digit while maintaining useful motion.
Fig. 4 The median nerves were noted to be markedly hypertrophic just proximal to the carpal ligament. Neural enlargement is a sign characteristic of macrodystrophia lipomatosa. The arrows point to the split fascicles of the hypertrophic right median nerve shown on axial MRI.
Repetitive debulking and syndactyly release surgeries would be required. Amputation of some or all of the involved digits was also discussed as an option. Careful counseling was provided, reinforcing that given the extent of the defects, it was unlikely that surgery would lead to a good functional or cosmetic outcome. The family decided to forego any surgical intervention. Yearly following-up is ongoing.
DISCUSSION Macrodystrophia lipomatosa is a non-hereditary congenital anomaly characterized by enlargement and hypertrophy of all mesenchymal elements including phalanges, tendons, nerves and vessels.13 Overgrowth occurs in a specific sclerotome region. The lower limb is more often involved than the upper limb, and in most cases multiple adjacent digits are affected, with the 2nd and 3rd digits being the most common.3 MDL usually presents unilaterally but is sometimes seen with bilateral limb involvement and can be complicated by syndactyly or polydactyly.1,6,8 The differential diagnosis of MDL can be seen in Table 1. Although most patients are initially asymptomatic, digital overgrowth can lead to interference with joint function, degenerative joint disease or cause neurovascular compression and entrapment.9,10 Patients most frequently present for evaluation for cosmetic reasons. Various surgical techniques have been described to treat macrodactyly caused by MDL. These have yielded some success, but inadequate correction and high recurrence rates continue to plague surgical outcomes. We report an unusual presentation of bilateral hand macrodactyly in a 23-month-old boy with associated anomalies including MDL, fibrolipomatous harmartoma (FLH),
June 25, 2013
9:36:16am
270
WSPC/135-HS
S. B. Albright et al.
Table 1 Diagnosis
Hand Surg. 2013.18:267-272. Downloaded from www.worldscientific.com by FLINDERS UNIVERSITY LIBRARY on 02/10/15. For personal use only.
FA1
1372018
Macrodactyly Differential Diagnosis and MRI Imaging Characteristics. Characteristics
Imaging
Neurofibromatosis (NF) type I
family history cafe-au-lait spots soft tissue nodules
T2W: marked hyperintensity adjacent to nerves. thinned bone shafts are present.
Hemangiomatosis
haemangiomas audible bruits
T2W: septate high-signal-intensity channels corresponding to the vascular channels and fibrous strands in haemangiomas.
Lymphangiomatosis
diffuse swelling pitting odema
T1W: hyperintense to muscle T2W: hyperintense to fat
Klippel-Trenaunay-Weber Syndrome
typical cutaneous capillary haemangiomas varicose veins
T2W: high-signal-intensity malformed venous and lymphatic lesions
Proteus Syndrome
T1W: diffuse high-signal-intensity characteristic of widespread fatty tissue.
Fibrolipomatous Hamartoma
tumour-like lipomatous process fatty tissue interspersed among nerve bundles endoneurial and perineurial fibrosis
MRI: speckled appearance as mature fat infiltrates the neural sheath
Macrodystrophia Lipomatosa
bony overgrowth fat deposition in subcutaneous tissues, tendons, muscles and nerves
MRI: fatty tissue appearance with enlargement of the mesenchymal tissues, bony enlargement, hypertrophy along a nerve territory, unilaterality, and demonstration of fat within the nerve sheath,
skull abnormalities pigmented nevi lung cysts intra-abdominal lipomas
complete syndactyly and partial synostosis of the affected distal phalanges. The most prominent pathologic finding in MDL is diffuse adipose infiltration of a fine meshwork of fibrous tissue that involves bone marrow, periosteum, muscles nerve sheaths and subcutaneous tissues.1 Phalanges are often elongated and broadened and the periosteum can be studded with small nodules consisting of chondroblasts, osteoblasts and osteoclasts. The nodules usually become larger and more numerous distally causing the terminal phalanges to sometimes have a characteristic mushroom-like appearance.11 The trabecular structure of affected phalanges generally remains well-preserved.8 Vessels of the affected digit are often proportionately enlarged without arteriovenous fistula or increased vascularity. Neural enlargement and irregularity is common and caused by perineural and endoneural fibrosis without an increase in number of axons. Commonly, MDL is associated with FLH, as seen in our patient. In FLH the deposition of fat is within the nerve sheath, while in MDL it occurs throughout the digit or extremity. MDL and FLH are associated in approximately 30% of
cases.9 Imaging is vital in establishing a diagnosis. MRI is considered by many the imaging modality of choice for evaluating MDL.9,10 MRI can be used for definitive diagnosis of MDL, as the fatty tissue appearance with enlargement of the mesenchymal tissues is characteristic for MDL. MRI easily demonstrates excess fibro-fatty tissue with fibrous strands present on T1-weighted imaging as linear strands of low-intensity signal.9,12 Radiologic investigations afford a noninvasive way to make a definitive diagnosis, differentiating MDL from other causes of localised hypertrophy and their respective prognoses, complications, and treatments (Table 1).9 Although the getiology of macrodystrophia lipomatosa has yet to be discovered, there have been many hypotheses proposed such as lipomatous degeneration,6 disturbed foetal circulation,13 erroneous segmentation,9 trophic influence of a tumified nerve,6 and the in utero disturbance of a growth-limiting factor during limb bud development.1 Recent literature has also suggested involvement of the PTEN gene (phosphatase and tensin homologue deleted on chromosome 10) which is primarily a tumour suppressor gene that significantly influences
June 25, 2013
9:36:16am
WSPC/135-HS
1372018
FA1
Hand Surg. 2013.18:267-272. Downloaded from www.worldscientific.com by FLINDERS UNIVERSITY LIBRARY on 02/10/15. For personal use only.
Macrodystrophia Lipomatosa with Syndactyly
cell and tissue growth.1,14 The possible involvement of PTEN in the etiology of MDL may suggest that MDL is a localised form of Proteus syndrome.1,14 PTEN gene involvement may explain the marked increase in adipose tissue, but further research is needed to prove the role of PTEN in MDL and its mechanism in disproportionate lipomatous formation.1,14 MDL generally comes to clinical attention due to cosmetic reasons. Parental concern for social acceptance is a strong motivator for parents to seek surgical treatment for a child at a young age. Obvious mechanical problems can also lead to early clinic presentation. Fibroadipose enlargement predominantly affects the volar aspect and distal portions of the digit, often resulting in dorsal deviation.15 This upward curvature of the digits causes difficulty with ambulation or hand function. Articular surfaces in the affected digit may also be slanted, further inhibiting function.8 In more severe cases, tissue bulk alone can restrict motion enough to significantly hinder function, as seen in our patient.16 Later presentations can include entrapment neuropathy and secondary osteoarthritis with formation of subchondral cysts and large osteophytes.9,11,16 It has been suggested that all MDL patients be tested with electrophysiologic studies in all limbs, even those unaffected, in order to assess for possible neuropathies.17 Surgical intervention should be based on the intent of correcting cosmetic appearance and improving mechanical function, while weighing the risks of possible complications or recurrence. The incidence of nerve injury following extensive debulking is approximately 3050% and the recurrence rate of excessive growth is at least 3360%.1,11 Various surgical approaches to treating macrodactyly have demonstrated inconsistent outcomes. Surgical interventions include digit reduction procedures (debulking, defatting, phalangectomy, arthrodesis and/or wedge osteotomies9,11,1719), growth limiting procedures (epiphysiodesis19), and ray amputations.18 Procedures aimed at digital reduction are most effective in less severe cases and for those patients who still retain some function. The most common methods use some combination of the described methods above. Due to poor vascularity relative to the overall mass of hypertrophic tissue and high rates of recurrence, staged surgeries are typically required. This allows time for revascularisation between successive debulking procedures.16 If epiphysiodesis is performed careful measurement and comparison to unaffected digits of the same sex parent must be made and the procedure timed accordingly in order to establish correct digit length.19 When central ray amputation is
271
performed, aesthetic appearance may be improved with adjacent digit transposition. The extent and type of surgical treatment should be based on the patient’s age, digital involvement, degree of motion, and severity of disease. In more complicated cases, efforts to reduce digit size while maintaining useful motion are pursued, but additional surgical considerations need to addressed. Grossly enlarged digits require staged surgeries for sequential debulking of each side of the digit.19 Several features influence the appearance of the digits besides the overall dimensions.19 Specifically, bulbous fingertips, angulation deformities, and associated anomalies, including polydactyly, brachydactyly, syndactyly, and symphalangism, need to be managed accordingly. Specific approaches include closing wedge osteotomies for angulation deformities, amputation for polydactyly, and syndactyly release. Multiple procedures are generally required and poor outcomes are expected.19 In these complicated situations, thorough patient and family counselling must be provided regarding the alternatives, risks, and realistic expectations for attempts at digitpreserving surgery. Given the progressive and diffuse nature of MDL, complete correction to normalcy is not always possible.20 Multiple procedures may be performed and still result in a deformed digit with limited function. Recurrence and further functional deterioration with continued growth often lead to subsequent amputation to improve hand function.20 When the macrodactylous digits are grossly deforming and nonfunctional, early ray amputation should be offered as definitive treatment. With pervasive bilateral upper extremity involvement, as in our patient’s condition, it is difficult to recommend amputation of multiple digits or to commit the patient to innumerable salvage procedures when the outcome is expected to be very poor. Extensive counselling and guidance for the parents become paramount when there are no good options to offer. In summary, we describe a previously unreported case of bilateral upper extremity macrodystrophia lipomatosa with syndactyly. We emphasised the importance of establishing a diagnosis with imaging and reviewed the described surgical approaches to treating this difficult condition. Severe forms of macrodactyly present unique problems with regard to patient management. When MDL involves multiple digits or extremities, it may be difficult to decide between amputations versus digit-preserving treatment plans. Informed decision-making after appropriate delivery of prognostic information and counselling will ultimately determine the best course of action.
June 25, 2013
9:36:17am
272
WSPC/135-HS
1372018
S. B. Albright et al.
References
Hand Surg. 2013.18:267-272. Downloaded from www.worldscientific.com by FLINDERS UNIVERSITY LIBRARY on 02/10/15. For personal use only.
FA1
1. Rohilla S et al., Macrodystrophia lipomatosa involving multiple nerves, J Orthop Trauma 13(1):4145, 2012. 2. Feriz H, Makrodystrophia lipomatosa progressiva, Virchows Archiv Pathol Anat Physiol Klin Med 260(2):308368, 1926. 3. Barsky AJ, Macrodactyly, J Bone Joint Surg Am 49(7):12551266, 1967. 4. Linder JM et al., Congenital anomalies of the hand: an overview, J Craniofac Surg 20(4):9991004, 2009. 5. Van Heest AE, Congenital disorders of the hand and upper extremity, Pediatr Clin North Am 43(5):11131133, 1996. 6. Kozin SH, Upper-extremity congenital anomalies, J Bone Joint Surg 85(8):15641576, 2003. 7. Stern PJ, Nyquist SR, Macrodactyly in ulnar nerve distribution associated with cubital tunnel syndrome, J Hand Surg Am 7(6):569571, 1982. 8. Gupta SK, et al., Macrodystrophia lipomatosa: radiographic observations, Br J Radiol 65(777):769773, 1992. 9. Singla V et al., Case report: Macrodystrophia lipomatosa — illustration of two cases, Indian J Radiol Imaging 18(4):298301, 2008. 10. Soler R et al., MR findings of macrodystrophia lipomatosa, Clin Imaging 21(2):135137, 1997. 11. Khan RA et al., Macrodystrophia lipomatosa: four case reports. Ital J Pediatr 36:69, 2010.
12. Koplay M, Kantarci M, Kilinc G, Macrodystrophia lipomatosa: multidetector CT and MRI findings, New Zealand Med J 125:1352, 2012. 13. Swanson AB, Barsky AJ, Entin MA, Classification of limb malformations on the basis of embryological failures, Surg Clin North Am 48(5):11691179, 1968. 14. Goberdhan DC, Wilson C, PTEN: tumour suppressor, multifunctional growth regulator and more, Hum Mol Genet 2:19, 2003. 15. D’Costa H et al., Magnetic resonance imaging in macromelia and macrodactyly, Br J Radiol 69(822):502507, 1996. 16. Watt AJ, Chung KC, Macrodystrophia lipomatosa: a reconstructive approach to gigantism of the foot, J Foot Ankle Surg 43(1):5155, 2004. 17. Kozanoglu E, Koc F, Goncu KI, Macrodystrophia lipomatosa with multiple entrapment neuropathies: a case report, Int J Neurosci 118 (4):545553, 2008. 18. Bulut M et al., Ray amputation for the treatment of macrodactyly in the foot: report of three cases, Acta Orthop Traumatol Turc 45(6):458462, 2011. 19. Akinci M, Ay S, Ercetin Ö, Surgical treatment of macrodactyly in older children and adults, J Hand Surg 29(6):10101019, 2004. 20. McCombe M, Kay SP, Macrodatyly, in Wolfe SW (ed.), Green’s Operative Hand Surgery, Elsevier, Philadelphia, pp. 14371444, 2005.
