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The Journal of Bone and Joint Surgery (American). 2007;89:1141-1150. doi:10.2106/JBJS.F.01540 © 2007 The Journal of Bone and Joint Surgery, Inc. What's New in Pediatric Orthopaedics
1 Texas Scottish Rite Hospital, 2222 Welborn Street, Dallas, TX 75219. E-mail
address:
dan.sucato{at}tsrh.org
Specialty Update has been developed in collaboration with the Council
of Musculoskeletal Specialty Societies (COMSS) of the American Academy of
Orthopaedic Surgeons.
Brachial Plexus Palsy Brachial plexus birth palsy occurs in association with 0.1% to 0.4% of live births. The majority of infants will demonstrate complete spontaneous recovery, but some will have persistent neurologic deficits requiring surgical intervention. Incomplete neurologic recovery leads to persistent limitations of active shoulder abduction and external rotation, often accompanied by an internal rotation contracture of the shoulder. In young patients, anterior releases of the pectoralis major, subscapularis, and/or anterior shoulder capsule combined with tendon transfers of the latissimus dorsi and teres major to the rotator cuff may provide significant improvement in global shoulder function. While effective in younger patients, latissimus dorsi and teres major tendon transfers are not a viable option in older patients with severe glenohumeral joint deformity. In these cases, external rotation osteotomies of the humerus may provide improvements in global shoulder function. Pearl et al.1 reported on a series of thirty-three children who were managed with arthroscopic release of the shoulder either alone (nineteen children) or in combination with a latissimus dorsi transfer (fourteen children). Four of the nineteen patients who had an isolated release required a later latissimus dorsi transfer because of recurrence of internal rotation contracture. The fourteen children who had a latissimus dorsi transfer in conjunction with the arthroscopic release were older, but none of them had recurrence of the contracture. Eighteen of the thirty-three patients had a pseudoglenoid deformity on magnetic resonance imaging, and the arthroscopic release restored the humeral head to a centered position in the joint in all eighteen. Waters and Bae2 reported on their experience with humeral derotation osteotomy in forty-three patients. The average rotational correction that was achieved during derotational humeral osteotomy was 64°, with the greatest functional improvement occurring in association with hand-to-mouth, hand-to-neck, and external rotation activities.
Shoulder Instability
Slipped Capital Femoral Epiphysis It is well documented that recognition of a slipped capital femoral epiphysis can be difficult because some patients may only present with a limp or knee pain. Loder et al.4 looked at the demographic factors (including gender, race, age, weight, height, and duration of symptoms at the time of diagnosis) associated with slip severity in patients with a stable slipped capital femoral epiphysis. They found that only age and the duration of symptoms were associated with slip severity. The final prediction model suggested that if the child is more than 12.5 years of age at the time of diagnosis, there is a twofold increased risk of having a slip angle in excess of 30°, and, if the duration of symptoms has been greater than two months, the risk of a moderate to severe slip is increased fourfold. In addition, Loder et al.5 reaffirmed the importance of age, height, and weight in distinguishing a typical idiopathic slipped capital femoral epiphysis from an atypical slipped capital femoral epiphysis due to conditions such as endocrinopathy, metabolic disorders, or radiation therapy. The single most useful predictor of endocrinopathy in patients with a slipped capital femoral epiphysis was found to be a height under the tenth percentile for age, which had a sensitivity of 75%, a specificity of 97%, a positive predictive value of 75%, and a negative predictive value of 97%.
Legg-Calvé-Perthes Disease
Developmental Acetabular Deformities: Protrusio, Dysplasia, Retroversion Acetabular protrusio can lead to limited range of hip motion and cartilage damage due to impingement and is common in Marfan syndrome. However, the natural history of joint degeneration and the prevalence of this deformity are not well understood. Sponseller et al.8, in a cross-sectional analysis of 173 patients with Marfan syndrome, looked at the prevalence of acetabular protrusio as well as the association between patient symptoms and radiographic changes associated with osteoarthritis and acetabular protrusio. The authors found that the prevalence of protrusio increased to approximately 35.9% by the age of twenty years and then it plateaued; however, its presence did not correlate with osteoarthritic changes as measured with the Iowa hip score in patients more than forty years of age. They found a significant positive correlation between protrusio and hip pain and a significant negative correlation between joint space width and protrusio in symptomatic hips, suggesting that mechanical factors from the protrusio are a contributor to joint degeneration but may not be the dominant factor. Acetabular retroversion occurs when there is anterior overcoverage of the femoral head by the anterior aspect of the acetabulum, and it is thought to be a cause of joint degeneration. Ezoe et al. looked at the prevalence of acetabular retroversion on the radiographs of the hips of patients with idiopathic osteoarthritis, developmental dysplasia, Legg-Calvé-Perthes disease, and adult-onset osteonecrosis. They found that normal hips and hips with adult-onset osteonecrosis had a 6% prevalence of acetabular retroversion. In contrast, the prevalence of acetabular retroversion was 18% for hips with developmental dysplasia and 42% for those with Legg-Calvé-Perthes disease. This study demonstrated that acetabular retroversion is commonly seen in patients with childhood developmental disorders. This is useful information when reconstructing these hips in order to avoid the creation of secondary impingement.
Congenital deficiency of the cruciate ligaments of the knee is rare, with a prevalence of approximately two per 100,000 live births, but it is commonly seen in association with congenital femoral deficiency and fibular hemimelia. Manner et al.9 analyzed thirty-four knees in limbs with congenital femoral deficiency and/or fibular hemimelia and found that 55% had hypoplasia or aplasia of the anterior cruciate ligament with a normal posterior cruciate ligament (type-I deficiency), 21% had aplasia of the anterior cruciate ligament and hypoplasia of the posterior cruciate ligament (type-II deficiency), and 24% had total absence of both cruciate ligaments (type-III deficiency). The radiographic appearance of the tibial spines and the femoral notch were characteristic for each type of dysplasia. In type-I deficiency, the lateral tibial spine was hypoplastic or aplastic. In type-II deficiency, the lateral tibial spine was aplastic and the medial spine was hypoplastic. In type-III deficiency, both tibial spines were aplastic. Additionally, with progressive severity of the dysplasia, there was progressive narrowing of the femoral notch. These plain radiographic changes in the knee can be used to rapidly assess possible ligamentous deficiencies in congenitally abnormal limbs. Traumatic anterior cruciate ligament injuries are four to six times more common in female athletes than in male athletes, and the majority occur in association with noncontact activities during sudden deceleration when running, changing direction, or landing from a jump. Pfeiffer et al.10 designed a prospective cohort study to look at the effectiveness of a plyometric-based exercise program to reduce the incidence of noncontact anterior cruciate ligament injuries in girls on 112 teams from fifteen high schools. The treatment group participated in the Knee Ligament Injury Prevention (KLIP) program, which is designed to improve jump-landing and running-deceleration mechanics and was performed twice a week. The incidence of anterior cruciate ligament injuries was 0.167 per 1000 exposures in the treatment group and 0.078 per 1000 exposures in the control group, suggesting no effect of this exercise program in the prevention of anterior cruciate ligament injuries.
Clubfoot deformity occurs in association with approximately one to two per 1000 live births. The goals of both surgical and nonsurgical treatment are to obtain initial correction of the foot deformity and then to maintain correction and function over time. Dobbs et al.11 performed a minimum twenty-five-year follow-up study of clubfeet that were treated with a soft-tissue surgical release. Forty-five patients with seventy-three clubfeet were managed with either a posterior release and plantar fasciotomy or an extensive combined posterior, medial, and lateral release. Thirty-nine of the forty-five patients required additional surgical procedures by the time of the latest follow-up, with most of those procedures being performed in adolescence or early adulthood. The mean functional score on the Laaveg-Ponseti scale was 65.3, which was significantly lower than the score of 87.5 in a comparable group of patients managed with the closed manipulation and casting method of Ponseti. None of the patients in the surgically treated group had an excellent result, and only one-third had a good result. There was significantly more radiographic evidence of arthritis in the feet that were treated surgically, and the amount of arthritis seen radiographically in the talonavicular joint appeared to correlate significantly with foot disability. Congenital vertical talus is an uncommon foot deformity that traditionally has been treated with surgical release. Dobbs et al.12 reported on their initial experience with eleven patients who were managed with a less invasive approach that appears to provide a good short-term outcome. With this approach, the foot is manipulated and then is casted using the Ponseti principles of weekly long-leg casting with gradual correction. The foot is stretched into plantar flexion and inversion while counterpressure is applied to the medial aspect of the head of the talus. In the study, a mean of five casts was required for reduction of the navicular onto the head of the talus. Most patients subsequently underwent percutaneous pinning of the talonavicular joint and a percutaneous heel cord tenotomy. Three patients also had fractional lengthening of the tibialis anterior or peroneal brevis tendon. The percutaneous pin was retained for five weeks and then was removed in the office. The foot was then placed into a solid ankle-foot orthosis in 15° of dorsiflexion to maintain reduction of the talonavicular joint. Six feet in three patients had a recurrent deformity as indicated by resubluxation of the navicular on the head of the talus. None of the six feet with recurrence, however, had pin fixation of the talonavicular joint. The authors concluded that cast immobilization following serial manipulation together with talonavicular pin fixation and tenotomy of the Achilles' tendon provides outstanding results in patients with idiopathic congenital vertical talus.
Growth Prediction Sanders et al.13, in a study of twenty-four skeletally immature girls, found that a Risser sign of 0 and an open tricartilage acetabular cartilage correlated with peak height velocity. They also noted that a radiograph of the hand is useful for determining whether the digital phalangeal epiphyses are capped (post-peak height velocity) or uncapped (pre-peak height velocity) because capping strongly correlates with the timing of peak height velocity, an important parameter to study when predicting curve progression. Dimeglio et al. identified the timing of the ossification of the olecranon and correlated it with peak growth velocity. These approaches have the advantage of allowing an easy and reliable assessment of skeletal age in six-month intervals during the two years of peak growth velocity.
Congenital Scoliosis
Scoliosis Bracing
Early-Onset Scoliosis and Thoracic Insufficiency There has been recent interest in the evaluation of patients who have a congenital spinal deformity together with chest wall abnormalities leading to thoracic insufficiency syndrome. The vertical expandable prosthetic titanium rib (VEPTR) has been effectively utilized for the treatment of these challenging patients by expanding the chest during the growing years to allow for maximum lung development while also treating the spinal deformity. The VEPTR is placed onto the chest wall and/or spine to achieve this correction. Mayer and Redding reported changes in pulmonary function after VEPTR insertion but demonstrated no significant change in FVC (forced vital capacity), FEV1 (forced expiratory volume in the first second of a forced expiratory maneuver), total lung capacity, or residual volume at the first postoperative visit. They stated that age has no impact on the change in pulmonary function and speculated that this lack of change in pulmonary function may indicate that lung volume preservation is occurring and that long-term improvements may occur. Similarly, Song et al. analyzed lung function in eleven children undergoing expansion thoracoplasty and demonstrated that improvements were seen in some, but not all, children. These improvements were not predicted by improvements in the Cobb angle. Vitale et al. administered the Child Health Questionnaire to the primary caretaker of patients with thoracic insufficiency syndrome and demonstrated significant perturbations in the quality of life, obtaining some of the lowest scores observed in the pediatric population. These data serve as an important baseline for future studies on patients undergoing expansion thoracoplasty. Flynn et al. reported two-year data on a multicenter population of twenty-four children who had undergone expansion thoracoplasty for the treatment of congenital spinal deformity. The authors reported improvements in the Cobb angle and the thoracic height over the treatment period. However, there were seven cases of device migration and infection or skin problems. Skaggs et al. reported a 2.1% incidence of neurologic injury during primary VEPTR device implantation, with a 1.4% incidence during device exchange and/or lengthening, which justifies the use of neurologic monitoring of both the upper and lower extremities in these patients. Patients who have a history of neurologic events related to VEPTR use are more prone to subsequent events.
Thoracic Pedicle Screws in Scoliosis
Neuromuscular Disorders
Anterior Surgery
Complications
Spondylolisthesis
Spinal Cord Monitoring
Forearm Fractures Price et al. analyzed reimbursement for and practice variation in the treatment of nondisplaced distal radial fractures and concluded that the avoidance of return visits saves money for patients and also provides greater reimbursement for physicians. The authors did caution that the study did not address clinical outcomes associated with this relatively minor injury. However, previous published reports by Price supported splint immobilization of buckle fractures without return appointments. Luhmann et al., in a study of 102 forearm fractures in children, compared the efficacy and adverse effects of two methods of analgesia: (1) a combination of ketamine and midazolam and (2) a combination of nitrous oxide and a hematoma block. Overall, the patients who had nitrous oxide and a hematoma block experienced lower increases in intra-procedure distress, less pain during fracture reduction, shorter recovery times, and fewer adverse effects. Jung et al., in a study of thirty children, compared two surgical techniques for the treatment of unstable distal bothbone forearm fractures: conventional Kirschner-wire fixation through the fracture line (sixteen patients) and Kirschnerwire fixation with use of the transulnar technique (fourteen patients). There were no differences between the groups in terms of healing time, operative time, duration of hospital stay, or complications. The authors concluded that the transulnar Kirschner wire fixation technique is a good alternative for the treatment of high-risk fractures because it avoids possible physeal injury, does not pass through the fracture line, and can provide satisfactory results.
Tibial Fractures
Supracondylar Fractures
Femoral Fractures
Stevens et al., in a prospective study of thirty-four consecutive patients with sixty-five segmental deformities who underwent implantation of an extraperiosteal 8-plate, reported that the guided growth associated with the use of the 8-plate provided a safe and cost-effective means of dealing with a variety of deformities in children. Sanders et al., in a study of thirty-seven patients who underwent screw epiphysiodesis for the correction of limb-length inequality and angular deformity, reported excellent angular correction overall, with the final limb-length difference averaging 0.1 cm. Complications were related directly to incorrect placement of screws or implant irritation. Scaduto et al., in a study of thirty-three limbs in thirty-one patients with transtibial amputations who underwent stump capping with use of the proximal part of the ipsilateral fibula, reported a 12% rate of failure (defined as the need for revision secondary to osseous overgrowth). The authors concluded that this method is associated with low morbidity and is an ideal way to prevent tibial overgrowth in children following amputation through the bone. Raney et al., in a review of 116 lower limb lengthening procedures in eighty-eight consecutive patients, demonstrated that lengthening was associated with an increased complication rate when patients who had a congenital limb-length discrepancy were compared with those who had an acquired deficiency, although the lengthening percentage in the patients who had a congenital deficiency was significantly higher. Stans et al., in a report on a series of 100 patients who were managed with excision of a partial physeal arrest, demonstrated that the average physeal growth was 78% in the femur, 88% in the proximal part of the tibia, and 93% in the distal part of the tibia. Finally, Gordon et al.19 analyzed the distal part of the femur in patients with infantile tibia vara and reported that the femur either was normal or had a varus deformity, with a mean lateral distal femoral angle of 97°. The mean median proximal tibial angle in these patients was 72°. The authors concluded that although patients with infantile tibia vara most commonly had normal alignment of the distal part of the femur, a substantial component of genu varum in children with late-onset disease may occur in the distal part of the femur and therefore this component should be considered when planning surgical treatment.
Cerebral Palsy Soo et al.20 reviewed their experience with 323 patients from their registry in order to determine the incidence of and risk factors for hip displacement in children with cerebral palsy. The hip displacement rate for the entire cohort was 35% and showed a linear relationship with the level of overall motor function. Chang et al. reviewed their experience with thirty-one children with neuromuscular hip dysplasia who underwent forty-one proximal femoral head resections. They reported a high rate of heterotopic ossification in patients who were managed with external fixation. However, 78% of the patients and families demonstrated improvement in terms of their responses to questions related to quality of life and 84% had improvement in their level of satisfaction. Szalay demonstrated that bone mineral density correlated with the prevalence of fractures in quadriparetic patients, but it is important to distinguish between patients who have a low body mass index and those who have a high body mass index when analyzing this fracture risk. Spiro et al., in a study of eighty-four children with spastic cerebral palsy who underwent a single-event multilevel surgical procedure, reported that the patients had improvement in motor function postoperatively and that the improvement was maintained over a period of five years. The patients who demonstrated the greatest change had had intermediate levels of motor function preoperatively. Otsuko et al., as part of a multicenter prospective study, analyzed fifty-seven patients who underwent multilevel surgery for the treatment of sagittal imbalance and gait disturbance and found that walking scores and quality of life scores improved. The global Pediatric Outcomes Data Collection Instrument (PODCI) score also improved, but no differences in the pain and happiness scores were seen. The authors concluded that their findings validated the use of multilevel surgery to improve sagittal balance and gait in patients with cerebral palsy. Michlitsch et al.21 analyzed the muscular contribution to varus foot deformities in a study of seventy-eight patients with cerebral palsy. The authors reported a higher prevalence of anterior tibialis dysfunction, both in isolation as well as in combination with posterior tibialis dysfunction, as a contributor to varus deformity in these patients than had been reported previously. Essentially one-third of the patients exhibited dysfunction of the tibialis anterior, one-third exhibited dysfunction of the tibialis posterior, and one-third exhibited dysfunction of both muscles. Molenaers et al.22, in a retrospective review of 424 children with cerebral palsy, analyzed the effect of gait analysis and the administration of botulinum toxin type-A on the timing and frequency of orthopaedic surgery. The authors demonstrated that there was a delay in surgical treatment in patients who had a combination of gait analysis and botulinum toxin injections, thus decreasing the frequency of surgical procedures.
Infection
Bone Tumors Futani et al.25, in a multicenter study, reported the results of a questionnaire that was administered to forty children who had had limb-salvage surgery for the treatment of a primary malignant tumor of the distal part of the femur. For those who survived, the final functional score was 74% in the endoprosthetic reconstruction group and 68% in the biological reconstruction group. For the nineteen patients who underwent limb-lengthening, the mean functional score increased significantly, from 62% before surgery to 81% after lengthening. In the endoprosthetic group the most frequent complications were deep infection and aseptic loosening, whereas in the biological reconstruction group the most common complications were implant breakage and nonunion. The authors concluded that both types of reconstruction can provide good functional results in skeletally mature children with malignant bone tumors of the distal aspect of the femur, despite a high rate of revisions and limb-lengthening procedures. In the study by Snyder et al.26, eighteen patients who presented with a fracture through a benign skeletal lesion were compared with eighteen patients who had an increased risk for fracture according to current radiographic criteria but had not had a fracture over a two-year period. The authors demonstrated that the combination of bending and torsional rigidity as measured with quantitative computed tomography was more accurate for predicting pathologic fractures through a benign bone lesion in children than standard radiographic criteria. They recommended this computed tomography-based method as a way of providing objective criteria for planning the treatment of benign lesions.
The editorial staff of The Journal reviewed a large number of recently published research studies related to the musculoskeletal system that received a Level of Evidence grade of I. Over 100 medical journals were reviewed to identify these articles, which all have high-quality study design. In addition to articles cited already in this Update, four additional level-I articles were identified that were relevant to pediatric orthopaedics. A list of those titles is appended to this review after the standard bibliography. We have provided a brief commentary about each of the articles to help to guide your further reading, in an evidence-based fashion, in this subspecialty area.
Betz RR, Petrizzo AM, Kerner PJ, Falatyn SP, Clements DH, Huss GK. Allograft versus no graft with a posterior multisegmented hook system for the treatment of idiopathic scoliosis. Spine. 2006;31:121-7. In this prospective, randomized study, ninety-one patients with adolescent idiopathic scoliosis were managed with posterior spinal fusion and instrumentation either with or without allograft augmentation. Seventy-six patients were followed for more than two years and were included in the analysis. The allograft group included thirty-seven patients, and the noallograft group included thirty-nine patients. Only one patient, in the allograft group, had a definite pseudarthrosis. Two patients in each group met the radiographic criteria for a possible pseudarthrosis, but there was no difference between the two groups with respect to this complication. There has certainly been a movement toward the use of allograft in order to achieve fusion in patients with adolescent idiopathic scoliosis when they undergo posterior spinal fusion and instrumentation. The question is whether the use of allograft is necessary. The authors designed a study to analyze this question and concluded that there was no difference between the two groups. However, the incidence of pseudarthrosis is somewhat challenging to define and perhaps, with the stiffer implants that are utilized today, a two-year follow-up is not adequate to fully assess healing. The authors also looked at a smaller subset of patients for a period of five years, and no patient in either group had a pseudarthrosis. This is promising work, and if the results hold true over time then this is certainly an advance in the management of these patients. Bohm ER, Bubbar V, Yong Hing K, Dzus A. Above and below-the-elbow plaster casts for distal forearm fractures in children. A randomized controlled trial. J Bone Joint Surg Am. 2006;88:1-8. In this blinded, randomized, controlled trial, 102 children were managed with either an above-the-elbow cast (fifty-six children) or a below-the-elbow cast (forty-six children) for the treatment of a forearm fracture. The authors demonstrated no difference between the groups with respect to initial fracture reduction, post-reduction angulation, reangulation during cast immobilization, or angulation of the fracture at the time of cast removal. Although several patients met the criteria for remanipulation of the fracture, only four patients actually underwent remanipulation. Those who were at most risk for remanipulation were those who had fractures of both the radius and the ulna as well as those with residual angulation after reduction. The authors noted that the complication rates did not differ between the two groups, and they concluded that either a below-the-elbow cast or an above-the elbow cast can be utilized for most of these fractures. Webb GR, Galpin RD, Armstrong DG. Comparison of short and long arm plaster casts for displaced fractures in the distal third of the forearm in children. J Bone Joint Surg Am. 2006;88:9-17. In this prospective study, 113 patients with a displaced fracture of the distal part of the forearm were randomized to treatment with either a short arm plaster cast (fifty-three) or a long arm plaster cast (sixty). There were no differences between the two groups with respect to preoperative factors, including demographic or fracture characteristics. There was no difference between the groups with regard to the change between the post-reduction and final radiographs. However, the patients who were managed with a short arm plaster cast were more independent with activities of daily living and missed fewer school days. The authors concluded that, for patients who are older than four years of age and who have a displaced fracture of the distal one-third of the forearm, short arm casts are as effective as long arm casts. This study and the study by Bohm et al. (discussed above) illustrate, in a well-defined patient population, that a well-molded plaster short arm cast is as effective as a long arm cast for maintaining good fracture reduction. The advantage of the short arm cast as shown in the study by Webb et al. is that patients are more independent with activities of daily living and do not need to miss as many school days because a revisit to the physician is not necessary to convert a long arm cast to a short arm cast. One of the things that was not studied and may be a further advantage is that parents most likely miss fewer work days and travel less to visit the physician when a short arm cast is utilized. These studies provide excellent evidence that a short arm cast is very effective for these patients, will decrease the need for multiple physician visits, and will allow children to maintain a more normal lifestyle than is the case when a long arm cast is utilized. Zeifang F, Carstens C, Schneider S, Thomsen M. Continuous passive motion versus immobilisation in a cast after surgical treatment of idiopathic club foot in infants: a prospective, blinded, randomised, clinical study. J Bone Joint Surg Br. 2005;87:1663-5. Patients who had had surgical treatment of a clubfoot deformity were randomized to either continuous passive motion (nineteen feet) or standard cast immobilization (eighteen feet). The patients were then blindly evaluated at six, twelve, eighteen, and forty months after surgery and were assigned a Dimeglio clubfoot score as the prime outcome measurement. The authors demonstrated that, at the time of early follow-up, the patients in the continuous passive motion group had improved Dimeglio clubfoot scores. However, after eighteen and forty-eight months, there were no differences between the two groups. One of the challenges following the surgical treatment of clubfoot is the stiffness, which can lead to pain in the long term. Although it may seem intuitive that continuous passive motion reduces stiffness following surgical treatment, the results of this study suggest that continuous passive motion does not have any intermediate-term benefit following surgical treatment. However, the outcome measures that were used in this study (Dimeglio scores) may not be ideal to fully assess flexibility and function. Given the results of the study, however, postoperative casting is certainly acceptable and appears to be an equally successful method when compared with continuous passive motion.
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Top
Upper Extremity
Hip
11° following implant removal after posterior spinal fusion and
instrumentation for the treatment of adolescent idiopathic scoliosis. The
increase in kyphosis correlated with decreased outcome scores. Burton et al.,
in a review of their experience with 208 consecutive patients undergoing
surgical treatment of adolescent idiopathic scoliosis, demonstrated a 9.1%
reoperation rate, with most reoperations being performed because of
pseudarthrosis, delayed deep infection, implant prominence, or
spondylolisthesis. Eight patients had late operative site pain, which was
directly related to the use of threaded transverse rod connectors. Those
devices have been replaced by closed drop entry transverse connectors
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