- Email: [email protected]
Sports participation of children with down syndrome
Orthop Clin N Am 34 (2003) 439 – 443
Sports participation of children with Down syndrome Jennifer Winell, MDa,*, Stephen W. Burke, MDb b
a Montefiore Medical Center, 111 East 210 Street, Bronx, NY 10467, USA Hospital for Special Surgery, 535 East 70 Street, New York, NY 10021, USA
Participation in sports has numerous benefits for children, including socialization, discipline, and physical fitness. This is no less true for children with disabilities including Down syndrome. Before participation in sports, however, several questions need to be answered: (1) Is the child ready to participate? (2) What type of sport is appropriate? And (3) What are the advantages/disadvantages of specific sports? Motor skill development, social development, and cognitive level need to be considered. Children with and without disabilities follow similar sequences in motor skill acquisition [1]. No specific guidelines are available for normal or disabled children to determine readiness for sports participation. The American Academy of Pediatrics [2] classifies sports as contact or noncontact. Contact sports involve collision (boxing, football, wrestling) or impact (basketball, diving, gymnastics). Noncontact sports are strenuous (aerobics, crew, swimming), moderately strenuous (badminton, table tennis), or nonstrenuous (archery, golf, riflery). A child’s disability plays a significant role in decision making, but specific guidelines are few. It would seem that, in general, children with disabilities, including Down syndrome, should avoid collision sports. Beneficial effects of sports include improvements in stamina, muscle strength and endurance, speed, agility, flexibility, and weight control [3]. All may be beneficial for children with disabilities, including Down syndrome.
* Corresponding author. E-mail address: [email protected] (J. Winell).
Down syndrome Since the publication of his treatise entitled ‘‘Observation on the Ethnic Classification of Idiots’’ [4], J. Langdon Down’s name has been attached to the clinical entity resulting from chromosome trisomy 21. With an incidence of 1 in 660 live births, Down syndrome is the most common malformation pattern in humans. Patients with this disorder have a characteristic facial appearance, with upwardly slanted palpebral fissures, epicanthal folds, and a round flat face. Intelligence is diminished (average IQ 50), with significant individual variation. Medical problems are frequent (Table 1) and have a significant impact on sports participation. Collaboration with the child’s medical specialists helps determine appropriate activity level. Orthopedic issues The musculoskeletal system is a frequent cause of discomfort and disability in Down syndrome patients and a cause for admission to an acute care hospital in more than 25% of patients with Down syndrome [5]. Areas of concern include cervical spine, hip and patellofemoral instabilities, and foot deformities. Cervical spine The major cervical spine concern in Down syndrome is instability. Occipito-atlantal instability has been reported but is rare and uncommonly clinically significant. Atlantoaxial instability, on the other hand, as determined by radiographic evidence of an atlantodens interval of 5 mm or more, is common and may
0030-5898/03/$ – see front matter D 2003 Elsevier Inc. All rights reserved. doi:10.1016/S0030-5898(03)00010-5
440
J. Winell, S.W. Burke / Orthop Clin N Am 34 (2003) 439–443
Table 1 Medical issues in Down syndrome Medical problem
Incidence (%)
Congenital heart disease Thyroid disease Leukemia Bowel disorders Eye disorders
50 5–8 1 13 35
be the most frequent orthopedic problem seen in Down syndrome. Several aspects of this condition are worthy of emphasis. Studies have found atlantoaxial instability in 10% to 30% of patients with Down syndrome depending on patient age at the time of study [5 – 9]. The instability appears related to ligamentous laxity seen with Down syndrome, but clinical correlation has been unsuccessful [8,10]. The youngest patient with Down syndrome – associated atlantoaxial instability that the authors are aware of was 3 years old. By adolescence, the incidence
approaches 10% to 30% [5 – 9]. In the longest longitudinal study available [8], 32 patients with Down syndrome were assessed with sequential cervical spine radiographs over 13 years. One of 32 had atlantoaxial instability at the start of the study, and 8 of 32 were unstable at final followup. Peuschel [9] similarly followed 95 patients with Down syndrome for 3 to 6 years. Seven patients developed atlantoaxial instability during that time. It appears that 12% [8] to 16% [11] of Down syndrome patients with instability develop neurologic signs and symptoms. Unfortunately, a patient may present catastrophically (Fig. 1A, B) with quadriplegia and death [8]. There are at least 13 cases of acute posttraumatic neurologic deficit related to atlantoaxial instability in Down syndrome in the literature [7,8,12,13]. Skeletal abnormalities of the upper cervical spine occur much more commonly in Down syndrome than in control groups [14] and include acquired changes such as ossiculum terminale [15], suggestive of oc-
Fig. 1. (A) Lateral radiograph showing atlantoaxial dislocation following a summersault. The patient immediately was quadriplegic and subsequently died. (B) Lateral radiograph 13 years previously shows no evidence of atlantoaxial instability.
J. Winell, S.W. Burke / Orthop Clin N Am 34 (2003) 439–443
cult laxity/instability. Cervical spondylosis is prevalent in Down syndrome adults [16] and a cause of cervical myelopathy. The value of lateral cervical spine flexion and extension radiographs have been questioned by some investigators [7,17], but, together with others [8,18,19], we find them quite valuable in conjunction with a detailed physical examination. Given the acquired nature of the problem [8], periodic followup examination seems prudent. A Down syndrome child with a normal radiograph and normal neurologic examination requires no activity restrictions other than collision sports. With the frequency of acquired atlantoaxial instability, one may reasonably question the advisability of directing a child with Down syndrome into any neck-stressing activity, regardless of radiologic normalcy.
441
When a patient with Down syndrome manifests progressive atlantoaxial instability or significant spondylosis and is neurologically intact, participation in all neck-stressing sports should not be allowed. The Special Olympics consider gymnastics, diving, (including diving starts in swimming), butterfly stroke, high jump, soccer, and pentathalon to be such sports. Use of a cervical collar, though alerting those around the patient that there is a cervical spine issue, probably does nothing to protect the spine. Periodic radiographic and clinical follow-up is recommended for this subgroup. When a patient with Down syndrome has progressive cervical spine instability or myelopathy, surgical stabilization by atlantoaxial fusion is considered. One must be aware of the very high complication rate associated with this procedure [10].
Fig. 2. (A) AP pelvis radiograph. This 7-year-old male patient with Down syndrome had painful, recurrent dislocations of the left hip. (B, C) Intraoperative arthrogram. The acetabulum and femoral head appear normal in shape and relationship to each other despite frank instability. (D) AP pelvis radiograph. The patient had pelvic and femoral osteotomies with capsular plication. His hip remains stable and pain-free.
442
J. Winell, S.W. Burke / Orthop Clin N Am 34 (2003) 439–443
Hip instability True congenital dislocation of the hip in Down syndrome is very rare [20]. Acquired hip instability, on the other hand, is somewhat more common, seen in about 5% [21,22] of Down syndrome patients. Its etiology appears to be primarily ligamentous laxity, but moderate increased anteversion also plays a role [23]. The natural history of established hip instability is progression [21,22] from acute dislocation to recurrent dislocation, habitual dislocation, and fixed dislocation. Though the initial dislocations may be accompanied by few symptoms, ultimately, the majority become symptomatic and may cause cessation of ambulation [22]. Because of poor results, once instability progresses to fixed dislocation, periodic hip clinical screening with radiographic assessment when indicated through childhood may be warranted [20]. Nonoperative treatment for instability [24] has been advocated by some investigators. Others researchers [21,25], including the authors, have found it ineffective. If a nonoperative approach is chosen, modification of sports activity is warranted to avoid complete hip dislocation. Definitive management of hip instability is surgical, and combinations of pelvic or femoral osteotomy with capsular plication have been advocated [21,25]. The senior author has good results combining pelvic and femoral osteotomies with capsular plication (Fig. 2A – D). After appropriate postoperative rehabilitation, resumption of full sports activity is a reasonable goal.
Progressive instability and deformity are potentially more serious problems. It is relatively uncommon for long-term fixed dislocation of the patella to cause progressive genu valgum, knee flexion contracture, external tibial rotation, and rotatory tibiofemoral subluxation [27]. Three patients in the Dugdale and Renshaw [26] series appear to have lost ambulation ability because of these deformities. We favor follow-up review of all Down syndrome patients with patellar instability. If symptomatic progressive deformity is found, surgical intervention is considered. Foot deformities Pes plano-valgus, metatarsus primus varus, and bunions are very common in patients with Down syndrome. The deformities are related to generalized ligamentous laxity and are generally well tolerated. Treatment is with appropriately fit shoes. Surgery rarely is indicated.
Summary Patients with Down syndrome, by virtue of ligamentous laxity, are prone to a number of orthopedic problems with potentially serious sequelae. These disorders need to be evaluated throughout childhood and, when detected, appropriately managed. Given such management, the child with Down syndrome should be able to participate actively in and derive benefits from sports activities.
Patellofemoral instability Patellofemoral dislocatability or dislocation occurs in 4% to 8% [5,26,27] of Down syndrome patients. It usually is well tolerated but may give rise to pain or progressive deformity. Dugdale and Renshaw [26] reported pain in 17% of their patients but, in general, the patients did well with nonoperative management despite fixed dislocations. Mendez et al [27] report similar results. No treatment or restriction is necessary for asymptomatic instability. For a child with symptoms, nonoperative treatment with a patellar sleeve, medication, and (if necessary) activity restriction is generally effective. If not, patellar realignment by lateral release, medial reefing, and distal realignment by semitendinosus tenodesis is appropriate. Long-term surgical outcome data are scarce. Inherent ligamentous laxity in the Down syndrome patients cannot be predictably overcome with various reefing procedures.
References [1] Kelso JAS, Clark CE. The development of movement control and coordination. New York: John Wiley & Sons; 1982. [2] American Academy of Pediatrics. Committee on Sports Medicine. Recommendations for participating in competitive sports. Pediatrics 1988;81:737 – 9. [3] Bar-Or O. Pediatric sports medicine for the practitioner. New York: Springer-Verlag; 1983. [4] Down JLH. Observations on the ethnic classification of idiots. Clinical lecture reports, volume 3. London: London Hospital; 1866. [5] Diamond LS, Lynne D, Sigmann B. Orthopedic disorders in patients with Down’s syndrome. Orthop Clin N Am 1981;12:57 – 71. [6] American Academy of Pediatrics. Committee on Sports Medicine. Atlantoaxial instability in Down syndrome. Pediatrics 1984;74:152 – 4.
J. Winell, S.W. Burke / Orthop Clin N Am 34 (2003) 439–443 [7] American Academy of Pediatrics. Committee on Sports Medicine. Atlantoaxial instability in Down syndrome. Subject review. Pediatrics 1995;96:151 – 4. [8] Burke SW, French HG, Roberts JM, Johnston II CE, Whitecloud III TE, Edmunds JO. Chronic atlanto-axial instability in Down syndrome. J Bone Joint Surg 1985;67-A:1356 – 60. [9] Peuschel SM, Scola FH. Atlantoaxial instability in individuals with Down syndrome: epidemiologic, radiographic, and clinical studies. Pediatrics 1987;80: 555 – 60. [10] Segal LS, Drummond DS, Zanotti RM, Ecker ML, Mubarak SJ. Complications of posterior arthrodesis of the cervical spine in patients who have Down syndrome. J Bone Joint Surg 1991;73-A:1547 – 54. [11] Peuschel SM, Herndon JH, Gelch MM, Senft KE, Scola FH, Goldberg MJ. Symptomatic atlantoaxial subluxation in persons with Down syndrome. J Pediatr Orthop 1984;4:682 – 8. [12] Davidson RG. Atlantoaxial instability in individuals with Down syndrome: a fresh look at the evidence. Pediatrics 1988;81:857 – 65. [13] Shikata J, Yamamuro Y, Mikawa H, Kobori M. Atlanto-axial subluxation in Down’s syndrome. Int Orthop 1989;13:187 – 92. [14] Peuschel SM, Scola FH, Tupper TT, Pezzullo JC. Skeletal anomalies of the upper cervical spine in children with Down syndrome. J Pediatr Orthop 1990;10: 607 – 11. [15] French HG, Burke SW, Roberts JM, Johnston II CE, Whitecloud T, Edmunds JO. Upper cervical ossicles in Down syndrome. J Pediatr Orthop 1987;7:69 – 71. [16] Olive PM, Whitecloud III TS, Bennett JT. Lower cer-
[17]
[18]
[19] [20] [21]
[22]
[23]
[24] [25]
[26]
[27]
443
vical spondylosis and myelopathy in adults with Down’s syndrome. Spine 1988;13:781 – 4. Selby KA, Newton RW, Gupta S, Hunt L. Clinical predictors and radiological reliability in atlantoaxial subluxation in Down’s syndrome. Arch Dis Child 1991;66:876 – 8. Cremers MJ, Ramos L, Bol E, van Gijn J. Radiological assessment of the atlantaxial distance in Down’s syndrome. Arch Dis Child 1993;69:347 – 50. Peuschel SM. Atlantoaxial instability and Down syndrome. Pediatrics 1988;81:879 – 80. Goldberg MJ. The dysmorphic child: an orthopedic perspective. New York: Raven Press; 1987. Aprin H, Zink WP, Hall JE. Management of dislocation of the hip in Down syndrome. J Pediatr Orthop 1985;5:428 – 31. Hresko MT, McCarthy JC, Goldberg MJ. Hip disease in adults with Down syndrome. J Bone Joint Surg 1993;75-B:604 – 7. Shaw ED, Beals RK. The hip joint in Down’s syndrome. A study of its structure and associated disease. Clin Orthop 1992;278:101 – 7. Green WB. Closed treatment of hip dislocation in Down syndrome. J Pediatr Orthop 1998;18:643 – 7. Bennet GC, Rang M, Roye DP, Aprin H. Dislocation of the hip in trisomy 21. J Bone Joint Surg 1982;64-B: 289 – 94. Dugdale TW, Renshaw TS. Instability of the patellofemoral joint in Down syndrome. J Bone Joint Surg 1986;68-A:405 – 13. Mendez AA, Keret D, MacEwen GD. Treatment of patellofemoral instability in Down’s syndrome. Clin Orthop 1988;234:148 – 58.
Sports participation of children with Down syndrome Jennifer Winell, MDa,*, Stephen W. Burke, MDb b
a Montefiore Medical Center, 111 East 210 Street, Bronx, NY 10467, USA Hospital for Special Surgery, 535 East 70 Street, New York, NY 10021, USA
Participation in sports has numerous benefits for children, including socialization, discipline, and physical fitness. This is no less true for children with disabilities including Down syndrome. Before participation in sports, however, several questions need to be answered: (1) Is the child ready to participate? (2) What type of sport is appropriate? And (3) What are the advantages/disadvantages of specific sports? Motor skill development, social development, and cognitive level need to be considered. Children with and without disabilities follow similar sequences in motor skill acquisition [1]. No specific guidelines are available for normal or disabled children to determine readiness for sports participation. The American Academy of Pediatrics [2] classifies sports as contact or noncontact. Contact sports involve collision (boxing, football, wrestling) or impact (basketball, diving, gymnastics). Noncontact sports are strenuous (aerobics, crew, swimming), moderately strenuous (badminton, table tennis), or nonstrenuous (archery, golf, riflery). A child’s disability plays a significant role in decision making, but specific guidelines are few. It would seem that, in general, children with disabilities, including Down syndrome, should avoid collision sports. Beneficial effects of sports include improvements in stamina, muscle strength and endurance, speed, agility, flexibility, and weight control [3]. All may be beneficial for children with disabilities, including Down syndrome.
* Corresponding author. E-mail address: [email protected] (J. Winell).
Down syndrome Since the publication of his treatise entitled ‘‘Observation on the Ethnic Classification of Idiots’’ [4], J. Langdon Down’s name has been attached to the clinical entity resulting from chromosome trisomy 21. With an incidence of 1 in 660 live births, Down syndrome is the most common malformation pattern in humans. Patients with this disorder have a characteristic facial appearance, with upwardly slanted palpebral fissures, epicanthal folds, and a round flat face. Intelligence is diminished (average IQ 50), with significant individual variation. Medical problems are frequent (Table 1) and have a significant impact on sports participation. Collaboration with the child’s medical specialists helps determine appropriate activity level. Orthopedic issues The musculoskeletal system is a frequent cause of discomfort and disability in Down syndrome patients and a cause for admission to an acute care hospital in more than 25% of patients with Down syndrome [5]. Areas of concern include cervical spine, hip and patellofemoral instabilities, and foot deformities. Cervical spine The major cervical spine concern in Down syndrome is instability. Occipito-atlantal instability has been reported but is rare and uncommonly clinically significant. Atlantoaxial instability, on the other hand, as determined by radiographic evidence of an atlantodens interval of 5 mm or more, is common and may
0030-5898/03/$ – see front matter D 2003 Elsevier Inc. All rights reserved. doi:10.1016/S0030-5898(03)00010-5
440
J. Winell, S.W. Burke / Orthop Clin N Am 34 (2003) 439–443
Table 1 Medical issues in Down syndrome Medical problem
Incidence (%)
Congenital heart disease Thyroid disease Leukemia Bowel disorders Eye disorders
50 5–8 1 13 35
be the most frequent orthopedic problem seen in Down syndrome. Several aspects of this condition are worthy of emphasis. Studies have found atlantoaxial instability in 10% to 30% of patients with Down syndrome depending on patient age at the time of study [5 – 9]. The instability appears related to ligamentous laxity seen with Down syndrome, but clinical correlation has been unsuccessful [8,10]. The youngest patient with Down syndrome – associated atlantoaxial instability that the authors are aware of was 3 years old. By adolescence, the incidence
approaches 10% to 30% [5 – 9]. In the longest longitudinal study available [8], 32 patients with Down syndrome were assessed with sequential cervical spine radiographs over 13 years. One of 32 had atlantoaxial instability at the start of the study, and 8 of 32 were unstable at final followup. Peuschel [9] similarly followed 95 patients with Down syndrome for 3 to 6 years. Seven patients developed atlantoaxial instability during that time. It appears that 12% [8] to 16% [11] of Down syndrome patients with instability develop neurologic signs and symptoms. Unfortunately, a patient may present catastrophically (Fig. 1A, B) with quadriplegia and death [8]. There are at least 13 cases of acute posttraumatic neurologic deficit related to atlantoaxial instability in Down syndrome in the literature [7,8,12,13]. Skeletal abnormalities of the upper cervical spine occur much more commonly in Down syndrome than in control groups [14] and include acquired changes such as ossiculum terminale [15], suggestive of oc-
Fig. 1. (A) Lateral radiograph showing atlantoaxial dislocation following a summersault. The patient immediately was quadriplegic and subsequently died. (B) Lateral radiograph 13 years previously shows no evidence of atlantoaxial instability.
J. Winell, S.W. Burke / Orthop Clin N Am 34 (2003) 439–443
cult laxity/instability. Cervical spondylosis is prevalent in Down syndrome adults [16] and a cause of cervical myelopathy. The value of lateral cervical spine flexion and extension radiographs have been questioned by some investigators [7,17], but, together with others [8,18,19], we find them quite valuable in conjunction with a detailed physical examination. Given the acquired nature of the problem [8], periodic followup examination seems prudent. A Down syndrome child with a normal radiograph and normal neurologic examination requires no activity restrictions other than collision sports. With the frequency of acquired atlantoaxial instability, one may reasonably question the advisability of directing a child with Down syndrome into any neck-stressing activity, regardless of radiologic normalcy.
441
When a patient with Down syndrome manifests progressive atlantoaxial instability or significant spondylosis and is neurologically intact, participation in all neck-stressing sports should not be allowed. The Special Olympics consider gymnastics, diving, (including diving starts in swimming), butterfly stroke, high jump, soccer, and pentathalon to be such sports. Use of a cervical collar, though alerting those around the patient that there is a cervical spine issue, probably does nothing to protect the spine. Periodic radiographic and clinical follow-up is recommended for this subgroup. When a patient with Down syndrome has progressive cervical spine instability or myelopathy, surgical stabilization by atlantoaxial fusion is considered. One must be aware of the very high complication rate associated with this procedure [10].
Fig. 2. (A) AP pelvis radiograph. This 7-year-old male patient with Down syndrome had painful, recurrent dislocations of the left hip. (B, C) Intraoperative arthrogram. The acetabulum and femoral head appear normal in shape and relationship to each other despite frank instability. (D) AP pelvis radiograph. The patient had pelvic and femoral osteotomies with capsular plication. His hip remains stable and pain-free.
442
J. Winell, S.W. Burke / Orthop Clin N Am 34 (2003) 439–443
Hip instability True congenital dislocation of the hip in Down syndrome is very rare [20]. Acquired hip instability, on the other hand, is somewhat more common, seen in about 5% [21,22] of Down syndrome patients. Its etiology appears to be primarily ligamentous laxity, but moderate increased anteversion also plays a role [23]. The natural history of established hip instability is progression [21,22] from acute dislocation to recurrent dislocation, habitual dislocation, and fixed dislocation. Though the initial dislocations may be accompanied by few symptoms, ultimately, the majority become symptomatic and may cause cessation of ambulation [22]. Because of poor results, once instability progresses to fixed dislocation, periodic hip clinical screening with radiographic assessment when indicated through childhood may be warranted [20]. Nonoperative treatment for instability [24] has been advocated by some investigators. Others researchers [21,25], including the authors, have found it ineffective. If a nonoperative approach is chosen, modification of sports activity is warranted to avoid complete hip dislocation. Definitive management of hip instability is surgical, and combinations of pelvic or femoral osteotomy with capsular plication have been advocated [21,25]. The senior author has good results combining pelvic and femoral osteotomies with capsular plication (Fig. 2A – D). After appropriate postoperative rehabilitation, resumption of full sports activity is a reasonable goal.
Progressive instability and deformity are potentially more serious problems. It is relatively uncommon for long-term fixed dislocation of the patella to cause progressive genu valgum, knee flexion contracture, external tibial rotation, and rotatory tibiofemoral subluxation [27]. Three patients in the Dugdale and Renshaw [26] series appear to have lost ambulation ability because of these deformities. We favor follow-up review of all Down syndrome patients with patellar instability. If symptomatic progressive deformity is found, surgical intervention is considered. Foot deformities Pes plano-valgus, metatarsus primus varus, and bunions are very common in patients with Down syndrome. The deformities are related to generalized ligamentous laxity and are generally well tolerated. Treatment is with appropriately fit shoes. Surgery rarely is indicated.
Summary Patients with Down syndrome, by virtue of ligamentous laxity, are prone to a number of orthopedic problems with potentially serious sequelae. These disorders need to be evaluated throughout childhood and, when detected, appropriately managed. Given such management, the child with Down syndrome should be able to participate actively in and derive benefits from sports activities.
Patellofemoral instability Patellofemoral dislocatability or dislocation occurs in 4% to 8% [5,26,27] of Down syndrome patients. It usually is well tolerated but may give rise to pain or progressive deformity. Dugdale and Renshaw [26] reported pain in 17% of their patients but, in general, the patients did well with nonoperative management despite fixed dislocations. Mendez et al [27] report similar results. No treatment or restriction is necessary for asymptomatic instability. For a child with symptoms, nonoperative treatment with a patellar sleeve, medication, and (if necessary) activity restriction is generally effective. If not, patellar realignment by lateral release, medial reefing, and distal realignment by semitendinosus tenodesis is appropriate. Long-term surgical outcome data are scarce. Inherent ligamentous laxity in the Down syndrome patients cannot be predictably overcome with various reefing procedures.
References [1] Kelso JAS, Clark CE. The development of movement control and coordination. New York: John Wiley & Sons; 1982. [2] American Academy of Pediatrics. Committee on Sports Medicine. Recommendations for participating in competitive sports. Pediatrics 1988;81:737 – 9. [3] Bar-Or O. Pediatric sports medicine for the practitioner. New York: Springer-Verlag; 1983. [4] Down JLH. Observations on the ethnic classification of idiots. Clinical lecture reports, volume 3. London: London Hospital; 1866. [5] Diamond LS, Lynne D, Sigmann B. Orthopedic disorders in patients with Down’s syndrome. Orthop Clin N Am 1981;12:57 – 71. [6] American Academy of Pediatrics. Committee on Sports Medicine. Atlantoaxial instability in Down syndrome. Pediatrics 1984;74:152 – 4.
J. Winell, S.W. Burke / Orthop Clin N Am 34 (2003) 439–443 [7] American Academy of Pediatrics. Committee on Sports Medicine. Atlantoaxial instability in Down syndrome. Subject review. Pediatrics 1995;96:151 – 4. [8] Burke SW, French HG, Roberts JM, Johnston II CE, Whitecloud III TE, Edmunds JO. Chronic atlanto-axial instability in Down syndrome. J Bone Joint Surg 1985;67-A:1356 – 60. [9] Peuschel SM, Scola FH. Atlantoaxial instability in individuals with Down syndrome: epidemiologic, radiographic, and clinical studies. Pediatrics 1987;80: 555 – 60. [10] Segal LS, Drummond DS, Zanotti RM, Ecker ML, Mubarak SJ. Complications of posterior arthrodesis of the cervical spine in patients who have Down syndrome. J Bone Joint Surg 1991;73-A:1547 – 54. [11] Peuschel SM, Herndon JH, Gelch MM, Senft KE, Scola FH, Goldberg MJ. Symptomatic atlantoaxial subluxation in persons with Down syndrome. J Pediatr Orthop 1984;4:682 – 8. [12] Davidson RG. Atlantoaxial instability in individuals with Down syndrome: a fresh look at the evidence. Pediatrics 1988;81:857 – 65. [13] Shikata J, Yamamuro Y, Mikawa H, Kobori M. Atlanto-axial subluxation in Down’s syndrome. Int Orthop 1989;13:187 – 92. [14] Peuschel SM, Scola FH, Tupper TT, Pezzullo JC. Skeletal anomalies of the upper cervical spine in children with Down syndrome. J Pediatr Orthop 1990;10: 607 – 11. [15] French HG, Burke SW, Roberts JM, Johnston II CE, Whitecloud T, Edmunds JO. Upper cervical ossicles in Down syndrome. J Pediatr Orthop 1987;7:69 – 71. [16] Olive PM, Whitecloud III TS, Bennett JT. Lower cer-
[17]
[18]
[19] [20] [21]
[22]
[23]
[24] [25]
[26]
[27]
443
vical spondylosis and myelopathy in adults with Down’s syndrome. Spine 1988;13:781 – 4. Selby KA, Newton RW, Gupta S, Hunt L. Clinical predictors and radiological reliability in atlantoaxial subluxation in Down’s syndrome. Arch Dis Child 1991;66:876 – 8. Cremers MJ, Ramos L, Bol E, van Gijn J. Radiological assessment of the atlantaxial distance in Down’s syndrome. Arch Dis Child 1993;69:347 – 50. Peuschel SM. Atlantoaxial instability and Down syndrome. Pediatrics 1988;81:879 – 80. Goldberg MJ. The dysmorphic child: an orthopedic perspective. New York: Raven Press; 1987. Aprin H, Zink WP, Hall JE. Management of dislocation of the hip in Down syndrome. J Pediatr Orthop 1985;5:428 – 31. Hresko MT, McCarthy JC, Goldberg MJ. Hip disease in adults with Down syndrome. J Bone Joint Surg 1993;75-B:604 – 7. Shaw ED, Beals RK. The hip joint in Down’s syndrome. A study of its structure and associated disease. Clin Orthop 1992;278:101 – 7. Green WB. Closed treatment of hip dislocation in Down syndrome. J Pediatr Orthop 1998;18:643 – 7. Bennet GC, Rang M, Roye DP, Aprin H. Dislocation of the hip in trisomy 21. J Bone Joint Surg 1982;64-B: 289 – 94. Dugdale TW, Renshaw TS. Instability of the patellofemoral joint in Down syndrome. J Bone Joint Surg 1986;68-A:405 – 13. Mendez AA, Keret D, MacEwen GD. Treatment of patellofemoral instability in Down’s syndrome. Clin Orthop 1988;234:148 – 58.