HIP ISSN 1120-7000
Hip Int 2015; 25 (2): 188-190 DOI: 10.5301/hipint.5000211
CASE REPORT
Hip dislocation following minor trauma in a patient with neurofibromatosis type 1: a case report and review of the literature Paul M. Dearden, Kathryn A. Lowery, Joanna Bates, Sandeep P. Datir Hull Royal Infirmary, Hull - UK
ABSTRACT Neurofibromatosis type 1 (NF-1) is a common autosomal dominant disorder which is known to have associated skeletal manifestations. There are documented cases of hip dislocation in NF-1, although it is a rare occurrence. Previous cases have been associated with intra-articular neurofibromas, acetabular protrusio and femoral deformities such as coxa valga and in one case increased femoral offset. The authors review the literature on pelvic manifestations and report a case of hip dislocation in a 19-year-old woman with neurofibromatosis-one following minor trauma believed to be secondary to markedly increased femoral offset. This case illustrates the effect the NF-1 can have on the anatomy of the proximal femur and one of the complications that can present to the orthopaedic surgeon, without the presence on an intra-articular neurofibroma. In a review of the literature the authors found only two other cases of hip dislocation associated with NF-1 that occurred without the presence of an intra-articular neurofibroma. Keywords: Hip, Dislocation, Atraumatic, Neurofibromatosis type-1, Von Recklinghausen
Introduction Neurofibromatosis type 1 (NF-1) was first reported by pathologist Friedrich von Recklinghausen who described the neural involvement associated with this disease (1, 2). NF-1 is a disease of neural crest origin, affecting ectodermal and mesodermal tissues. It represents one of the most common autosomal dominant disorders, affecting one in every 3,000 live births (1, 2). Several associations between NF-1 and the hip or proximal femur have been reported. These include intraosseous cystic lesions, intra-articular neurofibromas (3-8), periosteal bone proliferation, coxa valga (2) and increased femoral offset (8). Dislocations of the hip associated with NF-1 are a rare occurrence. Following a thorough review of the currently published literature, 15 cases of hip dislocation including our case have so far been attributed to NF-1. In total eight of these dislocaAccepted: November 4, 2014 Published online: March 13, 2015 Corresponding Author: Paul Dearden Hull Royal Infirmary Anlaby Road Hull East Yorkshire HU3 2JZ, UK [email protected]
tions appear to have occurred following minimal trauma (5-10) and the other seven cases were deemed atraumatic or spontaneous (3, 4, 11-14). We report a case of hip dislocation in a 19-year-old woman with NF-1 following minor trauma believed to be secondary to markedly increased femoral offset.
Case A 19-year-old female patient with a confirmed histological diagnosis of NF-1, from a previous excision of a plexiform neurofibroma from her anterior chest wall, presented to the emergency department with a painful left hip. The patient had tried to climb over a child safety gate in her home describing a flexion and abduction type movement and experienced pain, accompanied by a clicking sensation in her left groin. She denied any previous significant trauma or symptoms of pain, limp or instability. Her previous medical history included hypertension and nystagmus with chorioretinal atrophy. She is currently a full time mother and does not participate in sporting activities. In the emergency department her left leg was shortened, externally rotated with her hip held in slight flexion. She reported subjective reduced sensation affecting the L2 to L5 dermatomal distribution on the affected leg. There was no motor deficit identified and the patient had good lower limb pulses. Plain radiographs of the pelvis demonstrated a superolateral subluxation of the left hip with no evidence of fracture (Fig. 1). A pelvic CT was performed to rule out any significant © 2015 Wichtig Publishing
Dearden et al
189
Fig. 2 - Marked discrepancy in the hip offset of the patients’ left hip in comparison to the right.
(measured on x-ray) of the left hip was measured 63 mm, nearly twice that of the unaffected right side (35 mm). There was disruption of the normal bony architecture of the left proximal femur with cortical thinning and coarse trabecular pattern demonstrated. Post-reduction MRI scans of her pelvis revealed a small neurofibroma in rectus femoris but no evidence of intra-articular neurofibroma. A spinal MRI did not demonstrate any spinal neurofibroma or any evidence of nerve root compression to explain the patient’s neurological symptoms or to demonstrate any neuromuscular cause for her hip subluxation. Subsequently she has suffered no further episodes of subluxation. Fig. 1 - Superolateral subluxation of the left hip with no evidence of fracture.
fracture or intra articular bone fragments. There was a small bone fragment associated with the anterior aspect of the left acetabulum which was suggested to represent an injury to the acetabular labrum. Under conscious sedation and intravenous opiate analgesia, the hip was reduced in the emergency room using the reverse Bigelow’s method. The hip reduced easily with a palpable clunk and resolution of the pre-reduction deformity. Post-reduction radiographs confirmed a congruent reduction with no intra-articular soft tissue interposition or bone fragments. A limited post-reduction CT focused on the hip joint confirmed concentric reduction with no intra-articular bone fragments. The patient still demonstrated reduced sensation in the L2 to L5 dermatomal distribution post-reduction. She required no further treatment and was discharged weight bearing as tolerated with the use of crutches. Her paraesthesia had completely resolved at follow-up 6 weeks later. Analysis of the post-reduction x-ray demonstrated a marked discrepancy in the hip offset of the patient’s left hip in comparison to the right (Fig. 2). The femoral offset © 2015 Wichtig Publishing
Discussion Whilst neurofibromatosis is amongst the most common autosomal dominant inherited conditions, the orthopaedic manifestations of the disease still only rarely present to the orthopaedic team. Rates of hip dislocation amongst patients with NF1 are as yet unreported. The NF1 gene was identified in 1989. The locus is situated on chromosome 17q.11.2 (15). Although the allele is completely penetrant, spontaneous mutations can occur (9). Neurofibromas rarely present at birth and typically present in late childhood with greater than 80% presenting by the beginning of the second decade (15). Whilst up to 24% of NF-1 patients will present with spinal deformity, the osseous lesions commonly described, such as sphenoid dysplasia or thinning of long bone cortex, with or without pseudoarthrosis, are actually relatively uncommon (1). For the patient described in this case, the proposed mechanism of dislocation is altered hip joint biomechanics caused by a markedly increased femoral offset and valgus deformity. The patient also had leg length discrepancy of approx. 2 cm on the affected side (femoral origin). We think that these morphological changes could be due to focal isolated osseous effect/hypertrophy due to neurofibromatosis.
Hip dislocation in neurofibromatosis: a case report
190
Post-reduction MRI imaging did not demonstrate any peri or intra-articular neurofibromas causing local erosion or mass effect which have been reported (3-8). To our knowledge, only two cases of dislocation without evidence of intraarticular neurofibroma have been reported in the English literature (10, 11). In one case the authors attributed this to a neuropathic arthropathy secondary to a severe kyphoscoliois and spinal neurofibroma (11), the other to capsule laxity and atrophied hip musculature, the patient having no detectable neurofibroma or anatomical abnormality to result in dislocation of the hip (10). Imaging of the spine in our case did not demonstrate any lesions within the spinal cord. The patient in this case has had no further episodes of dislocation and has returned to her pre-injury level of mobility. The long-term prognosis for hip dislocation in NF1 is unclear. Reports of recurrent dislocation (8, 10) and progression to degenerative joint pathology (10) are both reported. It is also reported that patients requiring hip arthroplasty following recurrent dislocations or arthritis secondary to NF1 may experience continued problems with instability after hip joint replacement (10).
Disclosures Financial support: None. Conflict of interest: None.
References 1. 2. 3.
Crawford AH, Schorry EK. Neurofibromatosis in children: the role of the orthopaedist. J Am Acad Orthop Surg. 1999;7(4):217-230. Vitale MG, Guha A, Skaggs DL. Orthopaedic manifestations of neurofibromatosis in children: an update. Clin Orthop Relat Res. 2002;401:107-118. Kuroda M, Nakase H, Yasui N, Ochi T, Takahashi Y, Hirabayashi S. Non-traumatic dislocation of the hip in von Recklinghausen’s disease: a case report. RinsyouSeikeigeka (Clinical Orthopaedic Surgery). 1999;1151:1151-1154.
4. 5.
6. 7.
8. 9. 10.
11. 12.
13.
14. 15.
Haga N, Nakamura S, Taniguchi K, Iwaya T. Pathologic dislocation of the hip in von Recklinghausen’s disease: a report of two cases. J Pediatr Orthop. 1994;14(5):674-676. Guilleminet M, Creyssel J, de Mourgues G, Fischer L. (Von Recklinghausen’s neurofibromatosis. Congenital hypertrophy of the lower limb in childhood and spontaneous luxation of the homolateral hip in adult age). Presse Med. 1970;78(28):1269-1271. Lachiewicz PF, Salvati EA, Hely D, Ghelman B. Pathological dislocation of the hip in neurofibromatosis. A case report. J Bone Joint Surg Am. 1983;65(3):414-415. Nakasone S, Norimatsu H, Hamasaki N, et al. A case report of recurrent dislocation of the hip joint with neurofibromatosis. [Article in Japanese]. Seikeigeka to Saigaigeka Orthop Surg Traumatol. 1989;38(2):511-514. Galbraith JG, Butler JS, Harty JA. Recurrent spontaneous hip dislocation in a patient with neurofibromatosis type 1: a case report. J Med Case Reports. 2011;5(1):106. Phillips JE, McMaster MJ. Pathological dislocation of the hip in neurofibromatosis. J R Coll Surg Edinb. 1987;32(3):180-182. Odent T, Ranger P, Aarabi M, Hamdy RC, Fassier F. Total hip arthroplasty in a patient with neurofibromatosis type I and recurrent spontaneous hip dislocation. Can J Surg. 2004;47(3): 219-220. Lampasi M, Greggi T, Sudanese A. Pathological dislocation of the hip in neurofibromatosis: a case report. Chir Organi Mov. 2008;91(3):163-166. Endo H, Mitani S, Sugihara S, Kuroda T, Nakahara S, Ozaki T. Nontraumatic subluxation of the hip after spine surgery for scoliosis in a patient with von Recklinghausen’s disease. J Orthop Sci. 2007;12(5):510-514. Lucet L, Elayoubi L, Defives T, et al. [Anterior pathologic dislocation of the hip in adulthood complicating Von Recklinghausen neurofibromatosis]. [Article in French]. Rev Rhum Ed Fr. 1993;60(1):79-80. Kumar R, dos Reis Teixeira Neto A, Deavers MT, Amini B, Lewis VO. Spontaneous hip dislocation secondary to intraarticular neurofibroma: a case report. Skeletal Radiol. 2014;43(7):1007-1011. Feldman DS, Jordan C, Fonseca L. Orthopaedic manifestations of neurofibromatosis type 1. J Am Acad Orthop Surg. 2010; 18(6):346-357.
© 2015 Wichtig Publishing
Copyright of Hip International is the property of Wichtig Publishing srl and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use.
Hip Int 2015; 25 (2): 188-190 DOI: 10.5301/hipint.5000211
CASE REPORT
Hip dislocation following minor trauma in a patient with neurofibromatosis type 1: a case report and review of the literature Paul M. Dearden, Kathryn A. Lowery, Joanna Bates, Sandeep P. Datir Hull Royal Infirmary, Hull - UK
ABSTRACT Neurofibromatosis type 1 (NF-1) is a common autosomal dominant disorder which is known to have associated skeletal manifestations. There are documented cases of hip dislocation in NF-1, although it is a rare occurrence. Previous cases have been associated with intra-articular neurofibromas, acetabular protrusio and femoral deformities such as coxa valga and in one case increased femoral offset. The authors review the literature on pelvic manifestations and report a case of hip dislocation in a 19-year-old woman with neurofibromatosis-one following minor trauma believed to be secondary to markedly increased femoral offset. This case illustrates the effect the NF-1 can have on the anatomy of the proximal femur and one of the complications that can present to the orthopaedic surgeon, without the presence on an intra-articular neurofibroma. In a review of the literature the authors found only two other cases of hip dislocation associated with NF-1 that occurred without the presence of an intra-articular neurofibroma. Keywords: Hip, Dislocation, Atraumatic, Neurofibromatosis type-1, Von Recklinghausen
Introduction Neurofibromatosis type 1 (NF-1) was first reported by pathologist Friedrich von Recklinghausen who described the neural involvement associated with this disease (1, 2). NF-1 is a disease of neural crest origin, affecting ectodermal and mesodermal tissues. It represents one of the most common autosomal dominant disorders, affecting one in every 3,000 live births (1, 2). Several associations between NF-1 and the hip or proximal femur have been reported. These include intraosseous cystic lesions, intra-articular neurofibromas (3-8), periosteal bone proliferation, coxa valga (2) and increased femoral offset (8). Dislocations of the hip associated with NF-1 are a rare occurrence. Following a thorough review of the currently published literature, 15 cases of hip dislocation including our case have so far been attributed to NF-1. In total eight of these dislocaAccepted: November 4, 2014 Published online: March 13, 2015 Corresponding Author: Paul Dearden Hull Royal Infirmary Anlaby Road Hull East Yorkshire HU3 2JZ, UK [email protected]
tions appear to have occurred following minimal trauma (5-10) and the other seven cases were deemed atraumatic or spontaneous (3, 4, 11-14). We report a case of hip dislocation in a 19-year-old woman with NF-1 following minor trauma believed to be secondary to markedly increased femoral offset.
Case A 19-year-old female patient with a confirmed histological diagnosis of NF-1, from a previous excision of a plexiform neurofibroma from her anterior chest wall, presented to the emergency department with a painful left hip. The patient had tried to climb over a child safety gate in her home describing a flexion and abduction type movement and experienced pain, accompanied by a clicking sensation in her left groin. She denied any previous significant trauma or symptoms of pain, limp or instability. Her previous medical history included hypertension and nystagmus with chorioretinal atrophy. She is currently a full time mother and does not participate in sporting activities. In the emergency department her left leg was shortened, externally rotated with her hip held in slight flexion. She reported subjective reduced sensation affecting the L2 to L5 dermatomal distribution on the affected leg. There was no motor deficit identified and the patient had good lower limb pulses. Plain radiographs of the pelvis demonstrated a superolateral subluxation of the left hip with no evidence of fracture (Fig. 1). A pelvic CT was performed to rule out any significant © 2015 Wichtig Publishing
Dearden et al
189
Fig. 2 - Marked discrepancy in the hip offset of the patients’ left hip in comparison to the right.
(measured on x-ray) of the left hip was measured 63 mm, nearly twice that of the unaffected right side (35 mm). There was disruption of the normal bony architecture of the left proximal femur with cortical thinning and coarse trabecular pattern demonstrated. Post-reduction MRI scans of her pelvis revealed a small neurofibroma in rectus femoris but no evidence of intra-articular neurofibroma. A spinal MRI did not demonstrate any spinal neurofibroma or any evidence of nerve root compression to explain the patient’s neurological symptoms or to demonstrate any neuromuscular cause for her hip subluxation. Subsequently she has suffered no further episodes of subluxation. Fig. 1 - Superolateral subluxation of the left hip with no evidence of fracture.
fracture or intra articular bone fragments. There was a small bone fragment associated with the anterior aspect of the left acetabulum which was suggested to represent an injury to the acetabular labrum. Under conscious sedation and intravenous opiate analgesia, the hip was reduced in the emergency room using the reverse Bigelow’s method. The hip reduced easily with a palpable clunk and resolution of the pre-reduction deformity. Post-reduction radiographs confirmed a congruent reduction with no intra-articular soft tissue interposition or bone fragments. A limited post-reduction CT focused on the hip joint confirmed concentric reduction with no intra-articular bone fragments. The patient still demonstrated reduced sensation in the L2 to L5 dermatomal distribution post-reduction. She required no further treatment and was discharged weight bearing as tolerated with the use of crutches. Her paraesthesia had completely resolved at follow-up 6 weeks later. Analysis of the post-reduction x-ray demonstrated a marked discrepancy in the hip offset of the patient’s left hip in comparison to the right (Fig. 2). The femoral offset © 2015 Wichtig Publishing
Discussion Whilst neurofibromatosis is amongst the most common autosomal dominant inherited conditions, the orthopaedic manifestations of the disease still only rarely present to the orthopaedic team. Rates of hip dislocation amongst patients with NF1 are as yet unreported. The NF1 gene was identified in 1989. The locus is situated on chromosome 17q.11.2 (15). Although the allele is completely penetrant, spontaneous mutations can occur (9). Neurofibromas rarely present at birth and typically present in late childhood with greater than 80% presenting by the beginning of the second decade (15). Whilst up to 24% of NF-1 patients will present with spinal deformity, the osseous lesions commonly described, such as sphenoid dysplasia or thinning of long bone cortex, with or without pseudoarthrosis, are actually relatively uncommon (1). For the patient described in this case, the proposed mechanism of dislocation is altered hip joint biomechanics caused by a markedly increased femoral offset and valgus deformity. The patient also had leg length discrepancy of approx. 2 cm on the affected side (femoral origin). We think that these morphological changes could be due to focal isolated osseous effect/hypertrophy due to neurofibromatosis.
Hip dislocation in neurofibromatosis: a case report
190
Post-reduction MRI imaging did not demonstrate any peri or intra-articular neurofibromas causing local erosion or mass effect which have been reported (3-8). To our knowledge, only two cases of dislocation without evidence of intraarticular neurofibroma have been reported in the English literature (10, 11). In one case the authors attributed this to a neuropathic arthropathy secondary to a severe kyphoscoliois and spinal neurofibroma (11), the other to capsule laxity and atrophied hip musculature, the patient having no detectable neurofibroma or anatomical abnormality to result in dislocation of the hip (10). Imaging of the spine in our case did not demonstrate any lesions within the spinal cord. The patient in this case has had no further episodes of dislocation and has returned to her pre-injury level of mobility. The long-term prognosis for hip dislocation in NF1 is unclear. Reports of recurrent dislocation (8, 10) and progression to degenerative joint pathology (10) are both reported. It is also reported that patients requiring hip arthroplasty following recurrent dislocations or arthritis secondary to NF1 may experience continued problems with instability after hip joint replacement (10).
Disclosures Financial support: None. Conflict of interest: None.
References 1. 2. 3.
Crawford AH, Schorry EK. Neurofibromatosis in children: the role of the orthopaedist. J Am Acad Orthop Surg. 1999;7(4):217-230. Vitale MG, Guha A, Skaggs DL. Orthopaedic manifestations of neurofibromatosis in children: an update. Clin Orthop Relat Res. 2002;401:107-118. Kuroda M, Nakase H, Yasui N, Ochi T, Takahashi Y, Hirabayashi S. Non-traumatic dislocation of the hip in von Recklinghausen’s disease: a case report. RinsyouSeikeigeka (Clinical Orthopaedic Surgery). 1999;1151:1151-1154.
4. 5.
6. 7.
8. 9. 10.
11. 12.
13.
14. 15.
Haga N, Nakamura S, Taniguchi K, Iwaya T. Pathologic dislocation of the hip in von Recklinghausen’s disease: a report of two cases. J Pediatr Orthop. 1994;14(5):674-676. Guilleminet M, Creyssel J, de Mourgues G, Fischer L. (Von Recklinghausen’s neurofibromatosis. Congenital hypertrophy of the lower limb in childhood and spontaneous luxation of the homolateral hip in adult age). Presse Med. 1970;78(28):1269-1271. Lachiewicz PF, Salvati EA, Hely D, Ghelman B. Pathological dislocation of the hip in neurofibromatosis. A case report. J Bone Joint Surg Am. 1983;65(3):414-415. Nakasone S, Norimatsu H, Hamasaki N, et al. A case report of recurrent dislocation of the hip joint with neurofibromatosis. [Article in Japanese]. Seikeigeka to Saigaigeka Orthop Surg Traumatol. 1989;38(2):511-514. Galbraith JG, Butler JS, Harty JA. Recurrent spontaneous hip dislocation in a patient with neurofibromatosis type 1: a case report. J Med Case Reports. 2011;5(1):106. Phillips JE, McMaster MJ. Pathological dislocation of the hip in neurofibromatosis. J R Coll Surg Edinb. 1987;32(3):180-182. Odent T, Ranger P, Aarabi M, Hamdy RC, Fassier F. Total hip arthroplasty in a patient with neurofibromatosis type I and recurrent spontaneous hip dislocation. Can J Surg. 2004;47(3): 219-220. Lampasi M, Greggi T, Sudanese A. Pathological dislocation of the hip in neurofibromatosis: a case report. Chir Organi Mov. 2008;91(3):163-166. Endo H, Mitani S, Sugihara S, Kuroda T, Nakahara S, Ozaki T. Nontraumatic subluxation of the hip after spine surgery for scoliosis in a patient with von Recklinghausen’s disease. J Orthop Sci. 2007;12(5):510-514. Lucet L, Elayoubi L, Defives T, et al. [Anterior pathologic dislocation of the hip in adulthood complicating Von Recklinghausen neurofibromatosis]. [Article in French]. Rev Rhum Ed Fr. 1993;60(1):79-80. Kumar R, dos Reis Teixeira Neto A, Deavers MT, Amini B, Lewis VO. Spontaneous hip dislocation secondary to intraarticular neurofibroma: a case report. Skeletal Radiol. 2014;43(7):1007-1011. Feldman DS, Jordan C, Fonseca L. Orthopaedic manifestations of neurofibromatosis type 1. J Am Acad Orthop Surg. 2010; 18(6):346-357.
© 2015 Wichtig Publishing
Copyright of Hip International is the property of Wichtig Publishing srl and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use.
