REVIEW URRENT C OPINION
Hip problems in cerebral palsy: screening, diagnosis and treatment Cemil Yildiz a and Ismail Demirkale b
Purpose of review Spastic type is the most common form of cerebral palsy. The purpose of this review was to evaluate recent literature for current trends in the surveillance and treatment of spastic hip problems in cerebral palsy. Recent findings Cerebral palsy is still the most common physical disability in childhood in developed countries. Surveillance programs have had promising results in the detection of ‘at risk’ patients. However, neither regular radiographic screening nor surgical treatment indications and procedures have shown any progression in the last decade. In addition, recent studies have focused heavily on nonoperative treatment strategies to improve gait. Summary Cerebral palsy is a static encephalopathy causing myostatic contractures especially in the knee and hip. Unbalanced hip contractures can lead to silent hip dislocation. Surgical and rehabilitative approaches such as soft tissue lengthening and proximal femoral and pelvic osteotomies can help patients maintain function and comfort. Selective dorsal rhizotomy or Intrathecal Baclofen Pump insertion or, recently, noninvasive techniques such as neurodevelopmental therapy may help patients and caregivers cope with what is still a devastating and inexorably progressive disorder. Keywords cerebral palsy, diagnosis, screening, treatment
INTRODUCTION Cerebral palsy is a neurodevelopmental condition secondary to hypoxic–ischemic brain injury during the perinatal period of development [1]. It is the most common physical disability in childhood in developed countries [2,3]. As well as motor impairment, these patients also show a high rate of mental health problems, of which attention deficit hyperactivity disorder is the most common [4]. Gross motor potential is reached by age 5 in most cerebral palsy cases but the severity affects this issue, with more severe cases reaching maximum function earlier [5]. The motor impairment leading to abilities and limitations in these patients can be described by the five-level Gross Motor Function Classification System (GMFCS), in which precise attention is given to the patient’s ability for sitting, walking and wheeled mobility. The reported prevalence of hip problems in these patients varies between 2 and 75%. In addition, children who are not able to sit independently or have severe neurological involvement and high-grade GMFCS tend to have the worst prognosis
[6–8]. The muscular imbalance around the hip musculature causes progressive lateral subluxation of the femur from the acetabulum due to hyperactivity in the adductors and flexors and relatively weak abductors and extensors (Fig. 1). The early recognition of ‘at risk’ patients enables early appropriate interventions and avoids disappointing salvage procedures (Fig. 2).
SCREENING Hip surveillance can identify patients at high risk of silent progressive hip dislocation. Regular radiographic hip examination is an integral part of hip a
Gulhane Military Medical Academy, Department of Orthopaedics and Kecioren Education and Research Hospital, Department of Orthopaedics, Ankara, Turkey b
Correspondence to Professor Cemil Yildiz, MD, Gu¨lhane Military Medical Academy, Department of Orthopaedics and Traumatology Etlik, Ankara, 06018, Turkey. Tel: +90 536 983 11 35; e-mail: [email protected] Curr Opin Pediatr 2014, 26:85–92 DOI:10.1097/MOP.0000000000000040
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KEY POINTS A spastic hip can silently proceed to subluxation or dislocation. Therefore, patients with spastic diplegia or hemiplegia should have a baseline pelvis X-ray at the end of their first year and should be followed-up at 6-month intervals. With respect to RMP, CHAA can be a practical and noninvasive test to identify patients at risk of hip dislocation. Contemporary medicine focuses heavily on treating gait disturbances in cerebral palsy, but the gold standard for a child with an obvious hip disorder remains unchanged; soft tissue procedures along with bony corrections have satisfactory outcomes, especially when performed in single-event operations.
screening, though physical examination alone is not always reliable. A baseline radiographic view of the pelvis should be obtained at 12–18 months, and Spiegel suggested follow-up of these patients at 6-month intervals [9]. Shore et al. [10] proposed an algorithm for clinical assessment of a child with cerebral palsy. This algorithm consists of examination of the child’s spine, pelvis and lower limb
FIGURE 1. Bilateral hyperadduction in cerebral palsy (CP). 86
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FIGURE 2. A 7-year-old child with cerebral palsy (CP) showing bilateral neglected hip dislocations. Management of this patient’s hips requires salvage procedures due to uncontainable hips.
musculoskeletal system, sitting, walking and standing abilities of the child, pain, Modified Ashworth Scale (MAS) and determining GMFCS grade of the patient. Two critical components of clinical assessment for hip problems in cerebral palsy are assignment of GMFCS level and hip joint measurements. As for other neurological disorders, the management of hip problems in cerebral palsy requires exact determination of current developmental status of the child for proper treatment [11]. Therefore, the most commonly used grading system for functional status of cerebral palsy is GMFCS. In addition to this, a new scoring system, which evaluates the motor and mental status of the child, has been suggested [12]. The Bayley Scale of Infant Development-II (BCID-II) determines the current status by comparison with normative data. Though this system has been validated for Down’s syndrome, prematurity and prenatal drug exposure, the authors tried to validate the applicability of BCID-II for cerebral palsy. Although a strong correlation between BCID-II and GMFCS was found, the authors stated that the GMFCS is still the major tool for assessing the functional status of cerebral palsy. Likewise, MAS is the most commonly used diagnostic tool for evaluating spasticity [13]. However, Numanoglu et al. compared MAS and Modified Tardieu Scale (MTS) for spasticity and concluded that the reliability of the MTS was superior to MAS, and they suggested MTS for assessing spasticity in cerebral palsy. In a recent review by Gordon and Simkiss [14], children with hemiplegia and those with bilateral cerebral palsy who can walk independently at 30 months of age were found to have the lowest Volume 26 Number 1 February 2014
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Hi p problems in cerebral palsy Yildiz and Demirkale
risk of hip dislocation. Similarly to Flynn, Gordon and Simkiss [14] also suggested standardized methods for obtaining a true pelvis X-ray by positioning the patient with the contralateral knee and hip in maximal flexion in order to eliminate the effect of lumbar lordosis, which can produce an inlet view of the pelvis [6,9,14]. Recent studies on findings of pelvis X-rays in CP have demonstrated that Reimer’s Migration Percentage (RMP) and acetabular index are useful measurements for monitoring the hip [11,14,15]. As stated by Gordon and Simkiss [14], a hip with RMP greater than 33% or an acetabular index greater than 308 will likely progress and require further treatment or close monitoring. Divecha proposed a new clinical measurement of range of hip motion using a goniometer called Combined Hip Abduction Angle (CHAA) [15]. After passive stretching of hamstring and psoas muscles for 5 min, two examiners measure the angle between the axes of both thighs. They recommend that 408 of CHAA should be a threshold for further evaluation of the hip. This measurement seems to be a practical test for both hip abduction angle and prediction of lateral hip displacement.
DIAGNOSIS
FIGURE 3. Windblown hip appearance.
Most children with cerebral palsy are born with normal hips but gradual deterioration occurs in one or both hips due to tethering of the growth by contractures [9,10,16,17]. The three common tests that are used for physical examination in cerebral palsy are the Thomas test, Staheli test and popliteal angle measurement. In a study by Lee et al. [18], popliteal angle measurement was shown to be the most reliable test among physical tests for joint contractures. A comprehensive examination should also be made, including the pelvis and spine. In most patients, pelvic obliquity is due to primary infrapelvic deformity, and in turn this can lead to a compensatory lumbar scoliosis which has an apex toward the lower side of the pelvis. When one hip has an adduction contracture and the other hip has abduction contracture, then the pelvis has a windswept appearance known as ‘wind-blown hip’ (Fig. 3). In respect of these diagnostic modalities, recent research has focused on gait discordances that play an important role in the management of cerebral palsy. In a cross-sectional observational study by Kirkwood et al. [19], comparison was made between angular displacement of the pelvis and lower extremity joints between GMFCS I and II grades, and it was found that, although gait velocity, stride length, stance/swing and cycle time were similar in both grades, children with grade II GMFCS strikingly
reduce the amount of pelvic obliquity and hip adduction angles during the stance phase of gait. This study highlighted the importance of a physical therapy regimen for improving pelvic and hip mobility in early grades of GMFCS. To supplement GMFCS, Dziuba et al. [20] proposed an integral method to detect gait asymmetry and gait pattern that can provide a simple and fast test for clinicians. Their rationale for this study was that the evaluation of motor behavior and monitoring the progress of recovery cannot be done objectively in children with cerebral palsy. Gait analysis in these patients can be used to evaluate the effects of different treatment modalities on gait parameters [21]. RMP measures the containment of the femoral head within the acetabulum in the coronal plane by obtaining the percentage of width of femoral head migration beyond the Perkin’s line [22]. If the lateral margin of the acetabulum deforms and looks like a ‘gothic arch’ as in the advanced stages of the disease, Shore suggested using the midpoint of the lateral acetabular margin instead of Perkin’s line [10]. This can also be termed Type II sourcil, as the lateral corner is turned upward and lies above the weightbearing dome. In Type I sourcil, the lateral corner is well defined and lies below the weight-bearing dome. When the RMP is beyond 50%, the acetabular
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TREATMENT Early recognition of the spastic hip is the hallmark of treatment to prevent late complications and salvage procedures (Fig. 5) [23]. According to Larsson et al., outcome studies further emphasize that singleevent bilateral multilevel orthopedic surgery performed with the right indications has been shown to be effective in improving clinical parameters in children with cerebral palsy [24–27].
NONOPERATIVE TREATMENT
FIGURE 4. Clinical view of increased femoral antetorsion.
index is generally greater than 408. Increased anteversion in cerebral palsy is secondary to inhibition of derotation of the proximal femur during growth and can lead to ‘coxa valga’ appearance (Fig. 4). Together with plain radiographs, computerized tomography can be used to evaluate the bony acetabulum in detail and MRI can be used to demonstrate cartilage loss.
The front line of treatment is physical therapy in the early stages of cerebral palsy, which aims to provide functional range of motion and to attain functional walking by maintaining muscle length and preventing contractures. However, the exact consequences of physical therapy alone for disease progression and altering the natural history of the disease are still unknown. Although abduction orthosis can help to prevent loss of acquired range after therapy, compliance with brace treatment is poor and can lead to wind-blown hips or hyperabduction deformity. Recently, a custom-molded chair was found to prevent the progression of coxa valga deformity in patients with high grade GMFCS [28]. Gait training
HIP SCREENING by REIMER'S INDEX
30% – In case of failed STL or – Dislocated hip – If there is mild subluxation (RMP = 30%– 60%) – without torsional deformity – If passive abduction 60% in a child who is 30%) without torsional deformity of bone, when passive abduction is less than 30–458 and when there is a high degree of RMP in a child who is younger than 4 years of age. Psoas lengthening is still controversial; Flynn recommends dividing the tendon near the lesser trochanter in nonambulatory patients while dividing only the psoas tendon, leaving the iliacus intact, in ambulatory patients [6]. Neurectomy of the anterior branch of the obturator nerve should never be done in ambulatory patients. Also, performing neurectomy in nonambulatory patients is still debated because of secondary extension and abduction contractures. As noted by Spiegel et al. [9], longterm results of soft tissue procedures are related to RMP in the first year postoperatively. It should be kept in mind that soft tissue procedures are prophylactic and, although promising results can be obtained by soft tissue releases, regular follow-up is necessary [36]. Indications for hip reconstruction are failed soft tissue surgery and established subluxation or dislocation [37]. The decision can be made at the time of surgery by evaluating the femoral head and acetabulum for a conclusion as to whether reconstruction is appropriate or salvage options are needed. Options for hip reconstruction are open or percutaneous proximal femur varus derotational osteotomy, periacetabular osteotomies and soft tissue releases [38]. Usually a proximal femoral osteotomy is adequate when acetabular index is below 258 (Fig. 6a–c). The amount of derotation can be decided preoperatively by MRI, but Braatz et al. found no correlation between anteversion measured on MRI and mean hip rotation in stance either before or after osteotomy and concluded that intraoperative determination of the amount of derotation gives the best results according to gait analysis [39 ]. Internal hip rotation can persist, which can be obvious by intoeing on gait analysis, and internal hip rotation recurrence can be seen in patients who had undergone osteotomy at an early age [40]. The authors prefer 208 or more external than internal rotation at the end of osteotomy. The postoperative neck-shaft angle should be corrected according to the patient’s age; whenever possible, osteotomy should be postponed to 4 years of age or older due to a higher remodeling rate in younger children [41]. However, in a study by Dreher et al. [42], patients with a relatively older age were evaluated and recurrence was found only in a subset of their patients. The authors could not find any reason for recurrence. Further studies seem to be needed to explain recurrence. A practical way to determine the amount of femoral shortening is measuring the
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FIGURE 6. (a–b): Anteroposterior pelvis and frog lateral view shows a unilateral subluxated hip of a 5-year-old child with cerebral palsy. The Reimer’s migration percentage was 54.5%, the acetabular index was 158 and the acetabulum had type II sourcil. (c) The patient was successfully treated by varus producing proximal femoral derotation osteotomy. 90
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overlap at the osteotomy side while flexing the hip to 908 and when popliteal angle is at 08. In cases of acetabular deficiency (acetabular index>258) or Type II sourcil, a pelvic osteotomy is required. Most cases represent a posterolateral deficiency, whereas subtle cases have anterior deficiency. Volume reducing periacetabular osteotomies such as Pemberton and Dega osteotomies are indicated because of shallow and saucer shaped acetabulum. Open reduction should be tailored to pelvic osteotomy when RMP is greater than 70%. Salvage options include femoral head and neck resection, valgus osteotomy, femoral shortening, soft tissue interposition arthroplasty (McHale procedure), arthrodesis and total joint arthroplasty with hip or shoulder prosthesis [43]. The backgrounds for arthrodesis, shortening osteotomy and total joint arthroplasty are limited; although promising results have been published, they seem to be a matter of some debate [44]
CONCLUSION Cerebral palsy is a static encephalopathy causing myostatic contractures especially in the knee and hip. Unbalanced hip contractures can lead to silent hip dislocation. Hip surveillance is paramount and, if any risk is detected by pediatricians or family physicians, orthopedic referral is essential. Orthopedic surgeons must balance the benefits and risks of various treatment options. Botulinum toxin or SDR along with soft tissue procedures can help eliminate the need for future surgery, but, when hip subluxation or dislocation is obvious, reduction can be successfully accomplished with surgery. Acknowledgements None. Conflicts of interest There are no conflicts of interest.
REFERENCES AND RECOMMENDED READING Papers of particular interest, published within the annual period of review, have been highlighted as: & of special interest && of outstanding interest 1. Shalak L, Perlman JM. Hypoxic-ischemic brain injury in the term infant-current concepts. Early Hum Dev 2004; 80:125–141. 2. Novak I, Hines M, Goldsmith S, et al. Clinical prognostic messages from a systematic review on cerebral palsy. Pediatrics 2012; 130:e1285– e1312. 3. Cheong SK, Johnston LM. Systematic review of self-concept measures for primary school aged children with cerebral palsy. Res Dev Disabil 2013; 34:3566–3575. 4. Bjorgaas HM, Elgen I, Boe T, et al. Mental health in children with cerebral palsy: does screening capture the complexity? Sci World J 2013; 3:468402.
5. Morgan C, Novak I, Badawi N. Enriched environments and motor outcomes in cerebral palsy: systematic review and meta-analysis. Pediatrics 2013; 132:e735–e746. 6. Flynn JM, Miller F. Management of hip disorders in patients with cerebral palsy. J Am Acad Orthop Surg 2002; 10:198–209. 7. Shukla PY, Mann S, Braun SV, Gholve PA. Unilateral hip reconstruction in children with cerebral palsy: predictors for failure. J Pediatr Orthop 2013; 33:175–181. 8. Shore BJ, Yu X, Desai S, et al. Adductor surgery to prevent hip displacement in children with cerebral palsy: the predictive role of the Gross Motor Function Classification System. J Bone Joint Surg Am 2012; 94:326–334. 9. Spiegel DA, Flynn JM. Evaluation and treatment of hip dysplasia in cerebral palsy. Orthop Clin North Am 2006; 37:185–196. 10. Shore B, Spence D, Graham H. The role for hip surveillance in children with cerebral palsy. Curr Rev Musculoskelet Med 2012; 5:126–134. 11. Terjesen T. Development of the hip joints in unoperated children with cerebral palsy: a radiographic study of 76 patients. Acta Orthop 2006; 77:125– 131. 12. Lee JH, Lim HK, Park E, et al. Reliability and applicability of the Bayley Scale of Infant Development-II for children with cerebral palsy. Ann Rehabil Med 2013; 37:167–174. 13. Numanog˘lu A, Gu¨nel MK. Intraobserver reliability of modified Ashworth scale and modified Tardieu scale in the assessment of spasticity in children with cerebral palsy. Acta Orthop Traumatol Turc 2012; 46:196–200. 14. Gordon GS, Simkiss DE. A systematic review of the evidence for hip surveillance in children with cerebral palsy. J Bone Joint Surg Br 2006; 88:1492– 1496. 15. Divecha A, Bhaskar A. Utility of combined hip abduction angle for hip surveillance in children with cerebral palsy. Indian J Orthop 2011; 45:548–552. 16. Schoenecker JG. Pathologic hip morphology in cerebral palsy and Down syndrome. J Pediatr Orthop 2013; 33:S29–32. 17. Terjesen T. The natural history of hip development in cerebral palsy. Dev Med Child Neurol 2012; 54:951–957. 18. Lee KM, Lee J, Chung CY, et al. Pitfalls and important issues in testing reliability using intraclass correlation coefficients in orthopaedic research. Clin Orthop Surg 2012; 4:149–155. 19. Kirkwood RN, Franco Rde L, Furtado SC, et al. Frontal Plane motion of the pelvis and hip during gait stance discriminates children with diplegia levels I and II of the GMFCS. ISRN Pediatr 2012; 2012:163039. 20. Dziuba A, Bober T, Kobel-Buys K, et al. Integral method (IM) as a quantitative and objective method to supplement the GMFCS classification of gait in children with cerebral palsy (CP). Acta Bioeng Biomech 2013; 15:105–111. 21. Roche N, Pradon D, Cosson J, et al. Categorization of gait patterns in adults with cerebral palsy: a clustering approach. Gait Posture 2013; 12:433– 435. 22. Kim SM, Sim EG, Lim SG, et al. Reliability of hip migration index in children with cerebral palsy: the classic and modified methods. Ann Rehabil Med 2012; 36:33–38. 23. Novak I, McIntyre S, Morgan C, et al. A systematic review of interventions for children with cerebral palsy: state of the evidence. Dev Med Child Neurol 2013; 55:21. 24. Koca K, Yildiz C, Yurttas¸ Y, et al. Outcomes of multilevel orthopedic surgery in children with cerebral palsy [in Turkish]. Eklem Hastalik Cerrahisi 2011; 22:69– 74. 25. Kim HT, Jang JH, Ahn JM, et al. Early results of one-stage correction for hip instability in cerebral palsy. Clin Orthop Surg 2012; 4:139–148. 26. Larsson M, Ha¨gglund G, Wagner P. Unilateral varus osteotomy of the proximal femur in children with cerebral palsy: a five-year follow-up of the development of both hips. J Child Orthop 2012; 6:145–151. 27. Park MS, Chung CY, Kwon DG, et al. Prophylactic femoral varization osteotomy for contralateral stable hips in nonambulant individuals with cerebral palsy undergoing hip surgery: decision analysis. Dev Med Child Neurol 2012; 54:231–239. 28. Kim MO, Lee JH, Yu JY, et al. Changes of musculoskeletal deformity in severely disabled children using the custom molded fitting chair. Ann Rehabil Med 2013; 37:33–40. 29. Kim SJ, Kwak EE, Park ES, et al. Differential effects of rhythmic auditory && stimulation and neurodevelopmental treatment/Bobath on gait patterns in adults with cerebral palsy: a randomized controlled trial. Clin Rehabil 2012; 26:904– 914. This study is an important example of a current and modern approach to the treatment of gait disturbances in cerebral palsy. 30. Lee BK, Chon SC. Effect of whole body vibration training on mobility in children with cerebral palsy: a randomized controlled experimenter-blinded study. Clin Rehabil 2013; 27:599–607. 31. Willoughby K, Jachno K, Ang SG, et al. The impact of complementary and & alternative medicine on hip development in children with cerebral palsy. Dev Med Child Neurol 2013; 55:472–479. This article is a long-term evaluation of complementary and alternative medicine used to prevent progression of hip displacement and the need for reconstructive or salvage surgery in cerebral palsy. 32. Pin TW, Elmasry J, Lewis J. Efficacy of botulinum toxin A in children with cerebral palsy in Gross Motor Function Classification System levels IV and V: a systematic review. Dev Med Child Neurol 2013; 55:304–313.
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Orthopedics 33. Willoughby K, Ang SG, Thomason P, et al. The impact of botulinum toxin A and abduction bracing on long-term hip development in children with cerebral palsy. Dev Med Child Neurol 2012; 54:743–747. This randomized controlled trial aims to investigate the effect of 6-monthly Botulinum-A toxin injections plus SWASH (Sitting, Walking and Standing Hip orthosis) on the incidence of hip surgery after a mean 10-year follow-up. 34. Bolster EA, van Schie PE, Becher JG, et al. Long-term effect of selective dorsal rhizotomy on gross motor function in ambulant children with spastic bilateral cerebral palsy, compared with reference centiles. Dev Med Child Neurol 2013; 55:610–616. 35. Silva S, Nowicki P, Caird MS, et al. A comparison of hip dislocation rates and && hip containment procedures after selective dorsal rhizotomy versus intrathecal baclofen pump insertion in nonambulatory cerebral palsy patients. J Pediatr Orthop 2012; 32:853–856. There are few studies in literature comparing SDR and ITBP insertion. This article shows that reconstructive surgery and dislocation rates are similar in patients who have undergone SDR or ITBP. Reconstruction rates with either procedure were 25–32%. 36. Dhawale AA, Karatas AF, Holmes L, et al. Long-term outcome of reconstruction of the hip in young children with cerebral palsy. Bone Joint J 2013; 95-B:259–265. 37. Canavese F, Gomez H, Kaelin A, et al. Percutaneous pelvic osteotomy and intertrochanteric varus shortening osteotomy in nonambulatory GMFCS level IV and V cerebral palsy patients: preliminary report on 30 operated hips. J Pediatr Orthop B 2013; 22:1–7. &
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38. de Morais Filho MC, Neves DL, Abreu FP, et al. Does the level of proximal femur rotation osteotomy influence the correction results in patients with cerebral palsy? J Pediatr Orthop B 2013; 22:8–13. 39. Braatz F, Wolf SI, Gerber A, et al. Do changes in torsional magnetic & resonance imaging reflect improvement in gait after femoral derotation osteotomy in patients with cerebral palsy? Int Orthop 2013; 37:2193– 2198. This is the most recent gait analysis in patients with cerebral palsy. The study group was examined for changes in static and dynamic parameters of gait analysis after having undergone proximal femoral derotation osteotomy. 40. de Morais Filho MC, Kawamura CM, dos Santos CA, et al. Outcomes of correction of internal hip rotation in patients with spastic cerebral palsy using proximal femoral osteotomy. Gait Posture 2012; 36:201–204. 41. Davids JR, Gibson TW, Pugh LI, et al. Proximal femoral geometry before and after varus rotational osteotomy in children with cerebral palsy and neuromuscular hip dysplasia. J Pediatr Orthop 2013; 33:182–189. 42. Dreher T, Wolf SI, Heitzmann D, et al. Long-term outcome of femoral derotation osteotomy in children with spastic diplegia. Gait Posture 2012; 36:467–470. 43. Agashe M, Song SH, Tong XB, et al. Subtrochanteric valgus osteotomy with monolateral external fixator in hips for patients with severe cerebral palsy. Orthopedics 2013; 36:139–146. 44. Wright PB, Ruder J, Birnbaum MA, et al. Outcomes after salvage procedures for the painful dislocated hip in cerebral palsy. J Pediatr Orthop 2013; 33:505–510.
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Hip problems in cerebral palsy: screening, diagnosis and treatment Cemil Yildiz a and Ismail Demirkale b
Purpose of review Spastic type is the most common form of cerebral palsy. The purpose of this review was to evaluate recent literature for current trends in the surveillance and treatment of spastic hip problems in cerebral palsy. Recent findings Cerebral palsy is still the most common physical disability in childhood in developed countries. Surveillance programs have had promising results in the detection of ‘at risk’ patients. However, neither regular radiographic screening nor surgical treatment indications and procedures have shown any progression in the last decade. In addition, recent studies have focused heavily on nonoperative treatment strategies to improve gait. Summary Cerebral palsy is a static encephalopathy causing myostatic contractures especially in the knee and hip. Unbalanced hip contractures can lead to silent hip dislocation. Surgical and rehabilitative approaches such as soft tissue lengthening and proximal femoral and pelvic osteotomies can help patients maintain function and comfort. Selective dorsal rhizotomy or Intrathecal Baclofen Pump insertion or, recently, noninvasive techniques such as neurodevelopmental therapy may help patients and caregivers cope with what is still a devastating and inexorably progressive disorder. Keywords cerebral palsy, diagnosis, screening, treatment
INTRODUCTION Cerebral palsy is a neurodevelopmental condition secondary to hypoxic–ischemic brain injury during the perinatal period of development [1]. It is the most common physical disability in childhood in developed countries [2,3]. As well as motor impairment, these patients also show a high rate of mental health problems, of which attention deficit hyperactivity disorder is the most common [4]. Gross motor potential is reached by age 5 in most cerebral palsy cases but the severity affects this issue, with more severe cases reaching maximum function earlier [5]. The motor impairment leading to abilities and limitations in these patients can be described by the five-level Gross Motor Function Classification System (GMFCS), in which precise attention is given to the patient’s ability for sitting, walking and wheeled mobility. The reported prevalence of hip problems in these patients varies between 2 and 75%. In addition, children who are not able to sit independently or have severe neurological involvement and high-grade GMFCS tend to have the worst prognosis
[6–8]. The muscular imbalance around the hip musculature causes progressive lateral subluxation of the femur from the acetabulum due to hyperactivity in the adductors and flexors and relatively weak abductors and extensors (Fig. 1). The early recognition of ‘at risk’ patients enables early appropriate interventions and avoids disappointing salvage procedures (Fig. 2).
SCREENING Hip surveillance can identify patients at high risk of silent progressive hip dislocation. Regular radiographic hip examination is an integral part of hip a
Gulhane Military Medical Academy, Department of Orthopaedics and Kecioren Education and Research Hospital, Department of Orthopaedics, Ankara, Turkey b
Correspondence to Professor Cemil Yildiz, MD, Gu¨lhane Military Medical Academy, Department of Orthopaedics and Traumatology Etlik, Ankara, 06018, Turkey. Tel: +90 536 983 11 35; e-mail: [email protected] Curr Opin Pediatr 2014, 26:85–92 DOI:10.1097/MOP.0000000000000040
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KEY POINTS A spastic hip can silently proceed to subluxation or dislocation. Therefore, patients with spastic diplegia or hemiplegia should have a baseline pelvis X-ray at the end of their first year and should be followed-up at 6-month intervals. With respect to RMP, CHAA can be a practical and noninvasive test to identify patients at risk of hip dislocation. Contemporary medicine focuses heavily on treating gait disturbances in cerebral palsy, but the gold standard for a child with an obvious hip disorder remains unchanged; soft tissue procedures along with bony corrections have satisfactory outcomes, especially when performed in single-event operations.
screening, though physical examination alone is not always reliable. A baseline radiographic view of the pelvis should be obtained at 12–18 months, and Spiegel suggested follow-up of these patients at 6-month intervals [9]. Shore et al. [10] proposed an algorithm for clinical assessment of a child with cerebral palsy. This algorithm consists of examination of the child’s spine, pelvis and lower limb
FIGURE 1. Bilateral hyperadduction in cerebral palsy (CP). 86
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FIGURE 2. A 7-year-old child with cerebral palsy (CP) showing bilateral neglected hip dislocations. Management of this patient’s hips requires salvage procedures due to uncontainable hips.
musculoskeletal system, sitting, walking and standing abilities of the child, pain, Modified Ashworth Scale (MAS) and determining GMFCS grade of the patient. Two critical components of clinical assessment for hip problems in cerebral palsy are assignment of GMFCS level and hip joint measurements. As for other neurological disorders, the management of hip problems in cerebral palsy requires exact determination of current developmental status of the child for proper treatment [11]. Therefore, the most commonly used grading system for functional status of cerebral palsy is GMFCS. In addition to this, a new scoring system, which evaluates the motor and mental status of the child, has been suggested [12]. The Bayley Scale of Infant Development-II (BCID-II) determines the current status by comparison with normative data. Though this system has been validated for Down’s syndrome, prematurity and prenatal drug exposure, the authors tried to validate the applicability of BCID-II for cerebral palsy. Although a strong correlation between BCID-II and GMFCS was found, the authors stated that the GMFCS is still the major tool for assessing the functional status of cerebral palsy. Likewise, MAS is the most commonly used diagnostic tool for evaluating spasticity [13]. However, Numanoglu et al. compared MAS and Modified Tardieu Scale (MTS) for spasticity and concluded that the reliability of the MTS was superior to MAS, and they suggested MTS for assessing spasticity in cerebral palsy. In a recent review by Gordon and Simkiss [14], children with hemiplegia and those with bilateral cerebral palsy who can walk independently at 30 months of age were found to have the lowest Volume 26 Number 1 February 2014
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Hi p problems in cerebral palsy Yildiz and Demirkale
risk of hip dislocation. Similarly to Flynn, Gordon and Simkiss [14] also suggested standardized methods for obtaining a true pelvis X-ray by positioning the patient with the contralateral knee and hip in maximal flexion in order to eliminate the effect of lumbar lordosis, which can produce an inlet view of the pelvis [6,9,14]. Recent studies on findings of pelvis X-rays in CP have demonstrated that Reimer’s Migration Percentage (RMP) and acetabular index are useful measurements for monitoring the hip [11,14,15]. As stated by Gordon and Simkiss [14], a hip with RMP greater than 33% or an acetabular index greater than 308 will likely progress and require further treatment or close monitoring. Divecha proposed a new clinical measurement of range of hip motion using a goniometer called Combined Hip Abduction Angle (CHAA) [15]. After passive stretching of hamstring and psoas muscles for 5 min, two examiners measure the angle between the axes of both thighs. They recommend that 408 of CHAA should be a threshold for further evaluation of the hip. This measurement seems to be a practical test for both hip abduction angle and prediction of lateral hip displacement.
DIAGNOSIS
FIGURE 3. Windblown hip appearance.
Most children with cerebral palsy are born with normal hips but gradual deterioration occurs in one or both hips due to tethering of the growth by contractures [9,10,16,17]. The three common tests that are used for physical examination in cerebral palsy are the Thomas test, Staheli test and popliteal angle measurement. In a study by Lee et al. [18], popliteal angle measurement was shown to be the most reliable test among physical tests for joint contractures. A comprehensive examination should also be made, including the pelvis and spine. In most patients, pelvic obliquity is due to primary infrapelvic deformity, and in turn this can lead to a compensatory lumbar scoliosis which has an apex toward the lower side of the pelvis. When one hip has an adduction contracture and the other hip has abduction contracture, then the pelvis has a windswept appearance known as ‘wind-blown hip’ (Fig. 3). In respect of these diagnostic modalities, recent research has focused on gait discordances that play an important role in the management of cerebral palsy. In a cross-sectional observational study by Kirkwood et al. [19], comparison was made between angular displacement of the pelvis and lower extremity joints between GMFCS I and II grades, and it was found that, although gait velocity, stride length, stance/swing and cycle time were similar in both grades, children with grade II GMFCS strikingly
reduce the amount of pelvic obliquity and hip adduction angles during the stance phase of gait. This study highlighted the importance of a physical therapy regimen for improving pelvic and hip mobility in early grades of GMFCS. To supplement GMFCS, Dziuba et al. [20] proposed an integral method to detect gait asymmetry and gait pattern that can provide a simple and fast test for clinicians. Their rationale for this study was that the evaluation of motor behavior and monitoring the progress of recovery cannot be done objectively in children with cerebral palsy. Gait analysis in these patients can be used to evaluate the effects of different treatment modalities on gait parameters [21]. RMP measures the containment of the femoral head within the acetabulum in the coronal plane by obtaining the percentage of width of femoral head migration beyond the Perkin’s line [22]. If the lateral margin of the acetabulum deforms and looks like a ‘gothic arch’ as in the advanced stages of the disease, Shore suggested using the midpoint of the lateral acetabular margin instead of Perkin’s line [10]. This can also be termed Type II sourcil, as the lateral corner is turned upward and lies above the weightbearing dome. In Type I sourcil, the lateral corner is well defined and lies below the weight-bearing dome. When the RMP is beyond 50%, the acetabular
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TREATMENT Early recognition of the spastic hip is the hallmark of treatment to prevent late complications and salvage procedures (Fig. 5) [23]. According to Larsson et al., outcome studies further emphasize that singleevent bilateral multilevel orthopedic surgery performed with the right indications has been shown to be effective in improving clinical parameters in children with cerebral palsy [24–27].
NONOPERATIVE TREATMENT
FIGURE 4. Clinical view of increased femoral antetorsion.
index is generally greater than 408. Increased anteversion in cerebral palsy is secondary to inhibition of derotation of the proximal femur during growth and can lead to ‘coxa valga’ appearance (Fig. 4). Together with plain radiographs, computerized tomography can be used to evaluate the bony acetabulum in detail and MRI can be used to demonstrate cartilage loss.
The front line of treatment is physical therapy in the early stages of cerebral palsy, which aims to provide functional range of motion and to attain functional walking by maintaining muscle length and preventing contractures. However, the exact consequences of physical therapy alone for disease progression and altering the natural history of the disease are still unknown. Although abduction orthosis can help to prevent loss of acquired range after therapy, compliance with brace treatment is poor and can lead to wind-blown hips or hyperabduction deformity. Recently, a custom-molded chair was found to prevent the progression of coxa valga deformity in patients with high grade GMFCS [28]. Gait training
HIP SCREENING by REIMER'S INDEX
30% – In case of failed STL or – Dislocated hip – If there is mild subluxation (RMP = 30%– 60%) – without torsional deformity – If passive abduction 60% in a child who is 30%) without torsional deformity of bone, when passive abduction is less than 30–458 and when there is a high degree of RMP in a child who is younger than 4 years of age. Psoas lengthening is still controversial; Flynn recommends dividing the tendon near the lesser trochanter in nonambulatory patients while dividing only the psoas tendon, leaving the iliacus intact, in ambulatory patients [6]. Neurectomy of the anterior branch of the obturator nerve should never be done in ambulatory patients. Also, performing neurectomy in nonambulatory patients is still debated because of secondary extension and abduction contractures. As noted by Spiegel et al. [9], longterm results of soft tissue procedures are related to RMP in the first year postoperatively. It should be kept in mind that soft tissue procedures are prophylactic and, although promising results can be obtained by soft tissue releases, regular follow-up is necessary [36]. Indications for hip reconstruction are failed soft tissue surgery and established subluxation or dislocation [37]. The decision can be made at the time of surgery by evaluating the femoral head and acetabulum for a conclusion as to whether reconstruction is appropriate or salvage options are needed. Options for hip reconstruction are open or percutaneous proximal femur varus derotational osteotomy, periacetabular osteotomies and soft tissue releases [38]. Usually a proximal femoral osteotomy is adequate when acetabular index is below 258 (Fig. 6a–c). The amount of derotation can be decided preoperatively by MRI, but Braatz et al. found no correlation between anteversion measured on MRI and mean hip rotation in stance either before or after osteotomy and concluded that intraoperative determination of the amount of derotation gives the best results according to gait analysis [39 ]. Internal hip rotation can persist, which can be obvious by intoeing on gait analysis, and internal hip rotation recurrence can be seen in patients who had undergone osteotomy at an early age [40]. The authors prefer 208 or more external than internal rotation at the end of osteotomy. The postoperative neck-shaft angle should be corrected according to the patient’s age; whenever possible, osteotomy should be postponed to 4 years of age or older due to a higher remodeling rate in younger children [41]. However, in a study by Dreher et al. [42], patients with a relatively older age were evaluated and recurrence was found only in a subset of their patients. The authors could not find any reason for recurrence. Further studies seem to be needed to explain recurrence. A practical way to determine the amount of femoral shortening is measuring the
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FIGURE 6. (a–b): Anteroposterior pelvis and frog lateral view shows a unilateral subluxated hip of a 5-year-old child with cerebral palsy. The Reimer’s migration percentage was 54.5%, the acetabular index was 158 and the acetabulum had type II sourcil. (c) The patient was successfully treated by varus producing proximal femoral derotation osteotomy. 90
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Hi p problems in cerebral palsy Yildiz and Demirkale
overlap at the osteotomy side while flexing the hip to 908 and when popliteal angle is at 08. In cases of acetabular deficiency (acetabular index>258) or Type II sourcil, a pelvic osteotomy is required. Most cases represent a posterolateral deficiency, whereas subtle cases have anterior deficiency. Volume reducing periacetabular osteotomies such as Pemberton and Dega osteotomies are indicated because of shallow and saucer shaped acetabulum. Open reduction should be tailored to pelvic osteotomy when RMP is greater than 70%. Salvage options include femoral head and neck resection, valgus osteotomy, femoral shortening, soft tissue interposition arthroplasty (McHale procedure), arthrodesis and total joint arthroplasty with hip or shoulder prosthesis [43]. The backgrounds for arthrodesis, shortening osteotomy and total joint arthroplasty are limited; although promising results have been published, they seem to be a matter of some debate [44]
CONCLUSION Cerebral palsy is a static encephalopathy causing myostatic contractures especially in the knee and hip. Unbalanced hip contractures can lead to silent hip dislocation. Hip surveillance is paramount and, if any risk is detected by pediatricians or family physicians, orthopedic referral is essential. Orthopedic surgeons must balance the benefits and risks of various treatment options. Botulinum toxin or SDR along with soft tissue procedures can help eliminate the need for future surgery, but, when hip subluxation or dislocation is obvious, reduction can be successfully accomplished with surgery. Acknowledgements None. Conflicts of interest There are no conflicts of interest.
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Prophylactic femoral varization osteotomy for contralateral stable hips in nonambulant individuals with cerebral palsy undergoing hip surgery: decision analysis. Dev Med Child Neurol 2012; 54:231–239. 28. Kim MO, Lee JH, Yu JY, et al. Changes of musculoskeletal deformity in severely disabled children using the custom molded fitting chair. Ann Rehabil Med 2013; 37:33–40. 29. Kim SJ, Kwak EE, Park ES, et al. Differential effects of rhythmic auditory && stimulation and neurodevelopmental treatment/Bobath on gait patterns in adults with cerebral palsy: a randomized controlled trial. Clin Rehabil 2012; 26:904– 914. This study is an important example of a current and modern approach to the treatment of gait disturbances in cerebral palsy. 30. Lee BK, Chon SC. Effect of whole body vibration training on mobility in children with cerebral palsy: a randomized controlled experimenter-blinded study. Clin Rehabil 2013; 27:599–607. 31. Willoughby K, Jachno K, Ang SG, et al. The impact of complementary and & alternative medicine on hip development in children with cerebral palsy. Dev Med Child Neurol 2013; 55:472–479. This article is a long-term evaluation of complementary and alternative medicine used to prevent progression of hip displacement and the need for reconstructive or salvage surgery in cerebral palsy. 32. Pin TW, Elmasry J, Lewis J. Efficacy of botulinum toxin A in children with cerebral palsy in Gross Motor Function Classification System levels IV and V: a systematic review. Dev Med Child Neurol 2013; 55:304–313.
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Orthopedics 33. Willoughby K, Ang SG, Thomason P, et al. The impact of botulinum toxin A and abduction bracing on long-term hip development in children with cerebral palsy. Dev Med Child Neurol 2012; 54:743–747. This randomized controlled trial aims to investigate the effect of 6-monthly Botulinum-A toxin injections plus SWASH (Sitting, Walking and Standing Hip orthosis) on the incidence of hip surgery after a mean 10-year follow-up. 34. Bolster EA, van Schie PE, Becher JG, et al. Long-term effect of selective dorsal rhizotomy on gross motor function in ambulant children with spastic bilateral cerebral palsy, compared with reference centiles. Dev Med Child Neurol 2013; 55:610–616. 35. Silva S, Nowicki P, Caird MS, et al. A comparison of hip dislocation rates and && hip containment procedures after selective dorsal rhizotomy versus intrathecal baclofen pump insertion in nonambulatory cerebral palsy patients. J Pediatr Orthop 2012; 32:853–856. There are few studies in literature comparing SDR and ITBP insertion. This article shows that reconstructive surgery and dislocation rates are similar in patients who have undergone SDR or ITBP. Reconstruction rates with either procedure were 25–32%. 36. Dhawale AA, Karatas AF, Holmes L, et al. Long-term outcome of reconstruction of the hip in young children with cerebral palsy. Bone Joint J 2013; 95-B:259–265. 37. Canavese F, Gomez H, Kaelin A, et al. Percutaneous pelvic osteotomy and intertrochanteric varus shortening osteotomy in nonambulatory GMFCS level IV and V cerebral palsy patients: preliminary report on 30 operated hips. J Pediatr Orthop B 2013; 22:1–7. &
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38. de Morais Filho MC, Neves DL, Abreu FP, et al. Does the level of proximal femur rotation osteotomy influence the correction results in patients with cerebral palsy? J Pediatr Orthop B 2013; 22:8–13. 39. Braatz F, Wolf SI, Gerber A, et al. Do changes in torsional magnetic & resonance imaging reflect improvement in gait after femoral derotation osteotomy in patients with cerebral palsy? Int Orthop 2013; 37:2193– 2198. This is the most recent gait analysis in patients with cerebral palsy. The study group was examined for changes in static and dynamic parameters of gait analysis after having undergone proximal femoral derotation osteotomy. 40. de Morais Filho MC, Kawamura CM, dos Santos CA, et al. Outcomes of correction of internal hip rotation in patients with spastic cerebral palsy using proximal femoral osteotomy. Gait Posture 2012; 36:201–204. 41. Davids JR, Gibson TW, Pugh LI, et al. Proximal femoral geometry before and after varus rotational osteotomy in children with cerebral palsy and neuromuscular hip dysplasia. J Pediatr Orthop 2013; 33:182–189. 42. Dreher T, Wolf SI, Heitzmann D, et al. Long-term outcome of femoral derotation osteotomy in children with spastic diplegia. Gait Posture 2012; 36:467–470. 43. Agashe M, Song SH, Tong XB, et al. Subtrochanteric valgus osteotomy with monolateral external fixator in hips for patients with severe cerebral palsy. Orthopedics 2013; 36:139–146. 44. Wright PB, Ruder J, Birnbaum MA, et al. Outcomes after salvage procedures for the painful dislocated hip in cerebral palsy. J Pediatr Orthop 2013; 33:505–510.
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