Comparison of Growing Rod Instrumentation Versus Serial Cast Treatment for Early-Onset Scoliosis

STUDY DESIGN

A comparison of 2 methods of early-onset scoliosis treatment using radiographic measures and complication rates.

OBJECTIVES

To determine whether a delaying tactic (serial casting) has comparable efficacy to a surgical method (insertion of growing rod instrumentation [GRI]) in the initial phase of early-onset deformity management.

SUMMARY OF BACKGROUND DATA

Serial casts are used in experienced centers to delay operative management of curves of surgical magnitude (greater than 50°) in children up to age 6 years.

METHODS

A total of 27 casted patients from 3 institutions were matched with 27 patients from a multicenter database according to age (within 6 months of each other), curve magnitude (within 10° of each other), and diagnosis. Outcomes were compared according to major curve magnitude, spine length (T1-S1), duration and number of treatment encounters, and complications.

RESULTS

There was no difference in age (5.5 years) or initial curve magnitude (65°) between groups, which reflects the accuracy of the matching process. Six pairs of patients had neuromuscular diagnoses, 11 had idiopathic deformities, and 10 had syndromic scoliosis. Growing rod instrumentation patients had smaller curves (45.9° vs. 64.9°; p = .002) at follow-up, but there was no difference in absolute spine length (GRI = 32.0 cm; cast = 30.6 cm; p = .26), even though GRI patients had been under treatment for a longer duration (4.5 vs. 2.4 years; p < .0001) and had undergone a mean of 5.5 lengthenings compared with 4.0 casts. Growing rod instrumentation patients had a 44% complication rate, compared with 1 cast complication. Of 27 casted patients, 15 eventually had operative treatment after a mean delay of 1.7 years after casting.

CONCLUSIONS

Cast treatment is a valuable delaying tactic for younger children with early-onset scoliosis. Spine deformity is adequately controlled, spine length is not compromised, and surgical complications associated with early GRI treatment are avoided.

Closed bone graft epiphysiodesis for avascular necrosis of the capital femoral epiphysis

BACKGROUND

Avascular necrosis (AVN) of the capital femoral epiphysis (CFE) after an unstable slipped capital femoral epiphysis (SCFE), femoral neck fracture or traumatic hip dislocation can result in severe morbidity. Treatment options for immature patients with AVN are limited, including a closed bone graft epiphysiodesis (CBGE). However, it is unclear whether this procedure prevents AVN progression.

QUESTIONS/PURPOSES

We investigated whether early MRI screening and CBGE prevented the development of advanced AVN changes in the CFE and the rates of complications with this approach.

METHODS

We prospectively followed all 13 patients (seven boys, six girls) with unstable SCFEs (six patients), femoral neck fractures (five patients), and traumatic hip dislocations (two patients) and evidence of early AVN treated between 1984 and 2012. Mean age at initial injury was 12 years (range, 10-16 years). Nine of the 13 patients had followup of at least 2 years or until conversion to THA (mean, 4.5 years; range, 0.8-8.5 years), including two with unstable SCFEs, the five with femoral neck fractures, and the two with traumatic hip dislocations. All patients had technetium scans and/or MRI within 1 to 2 months of their initial injury (before CBGE) and all had evidence of early (Ficat 0) AVN. Patients were followed clinically and radiographically for AVN progression.

RESULTS

Six of the nine hips did not develop typical clinical or radiographic evidence of AVN. These six patients have been followed 6.3 years (range, 4.3-9.1 years) from initial injury and 5.9 years (range, 3.8-8.5 years) from CBGE. The remaining three patients were diagnosed with AVN at periods ranging from 3 to 6 months after CBGE.

CONCLUSIONS

Early recognition and treatment of AVN with a CBGE may alter the natural history of this complication.

LEVEL OF EVIDENCE

Level IV, therapeutic study. See Instructions for Authors for a complete description of levels of evidence.

Evaluating the extent of clinical uncertainty among treatment options for patients with early-onset scoliosis

BACKGROUND

Literature guiding the management of early-onset scoliosis consists primarily of studies with a low level of evidence. Evaluation of clinical equipoise (i.e., when there is no known superiority among treatment modalities) allows for prioritization of research efforts. The objective of this study was to evaluate areas of clinical uncertainty among pediatric spine surgeons regarding the treatment of early-onset scoliosis.

METHODS

Fourteen experienced pediatric spine surgeons participated in semistructured interviews to identify clinical variables that influence decision making in the treatment of early-onset scoliosis. A series of case scenarios of 315 patients with idiopathic and neuromuscular early-onset scoliosis was then developed to be representative of those encountered in clinical practice. Using an online survey, eleven surgeons selected their choice of eight treatment options for each case scenario. Associations between case characteristics and treatment choices were assessed with chi-square and logistic regression analysis. Participants then reviewed the areas of treatment uncertainty identified in the survey, nominated additional research questions of interest, and ranked their interest to further explore the identified research questions.

RESULTS

Collective equipoise was identified in numerous scenarios in the survey spanning a range of ages and magnitudes of scoliosis, and additional questions were identified during the nominal group technique. Areas that had the greatest clinical uncertainty included the management of patients who have finished treatment with a growing-rod, timing of rod-lengthening intervals, and indications for spine-based and rib-based proximal instrumentation anchors. The use of rib anchors compared with spine-based anchors was ranked highly for consideration in future clinical trials.

CONCLUSIONS

Variability in decision making with regard to the optimum treatment of certain subsets of patients with early-onset scoliosis reflects gaps in the available evidence. Structured consensus methods identified priorities for higher levels of research in this area of scoliosis. Higher-level studies, including randomized trials, should focus on answering the questions highlighted in this report.

Obesity negatively affects spinal surgery in idiopathic scoliosis

BACKGROUND

Are obese patients with idiopathic scoliosis undergoing spinal surgery at higher risk for perioperative complications? This is not clearly understood. One previous study showed a greater preoperative thoracic kyphosis but no increase in perioperative complications.

QUESTIONS/PURPOSES

We asked whether obese adolescents with idiopathic scoliosis have more perioperative complications and decreased curve correction.

METHODS

We retrospectively reviewed 478 patients with idiopathic scoliosis operated on from 1998 to 2010. There were 236 (187 females, 49 males) with a mean age of 14 years (range, 11-22 years) who met the inclusion criteria. Demographic data, radiographic measurements, perioperative data, and major and minor complications were recorded. The BMI percentile (BMI%) defined two patient groups: healthy weight (BMI%<85) (n=181) and obese (BMI%≥85) (n=55). The preoperative curves were similar in the two groups. Minimum followup was 2 years (mean, 6 years; range, 2-14 years).

RESULTS

Postoperatively, the mean major curve was smaller for healthy-weight patients (20°; range, 8°-36°) than for obese patients (23.2°; range, 12°-56°), as was the mean kyphosis (31.1° [range, 10°-56°]) versus 36° [range, 15°-33°], respectively). The postoperative lordosis was similar in both groups. Increased BMI% correlated with increased operative time, intraoperative blood loss, amount of intraoperative crystalloids, and difficulty with administration of spinal anesthesia.

CONCLUSIONS

Obese patients are at higher risk for perioperative complications when undergoing spinal deformity surgery. Counseling should be done with the patient and family and weight loss recommended before surgery.

LEVEL OF EVIDENCE

Level IV, prognostic study. See Instructions for Authors for a complete description of levels of evidence.

An anatomic study of the epiphyseal tubercle and its importance in the pathogenesis of slipped capital femoral epiphysis

BACKGROUND

It has been proposed that the epiphyseal tubercle on the inferior surface of the capital femoral epiphysis may be responsible for the clinical distinction between a stable and an unstable slipped capital femoral epiphysis (SCFE). The anatomy of the tubercle and its relationship to the lateral epiphyseal vessels have not previously been rigorously defined.

METHODS

Twenty-two cadaveric capital femoral epiphyses from donors who had been three to seventeen years of age were analyzed and then digitized with use of a high-resolution laser scanner. The height, location, and approximate surface area of the epiphyseal tubercle were measured and were normalized to the size of the entire capital femoral epiphysis.

RESULTS

In all specimens except that from the youngest donor, the foramina for the lateral epiphyseal vessels were visible and were located directly superior to the epiphyseal tubercle. The height of the epiphyseal tubercle was 4.4 ± 1.1 mm. When normalized to the overall size of the capital femoral epiphysis, the relative height (r = 0.71) and relative area (r = 0.56) of the epiphyseal tubercle decreased with increasing age. The epiphyseal tubercle was consistently located in the posterosuperior quadrant, with its position being more posterior and less superior in specimens from younger donors.

CONCLUSIONS

The epiphyseal tubercle appears to be a major stabilizer, or keystone, of the capital femoral epiphysis and the lateral epiphyseal vessels. Its relative decrease in height and surface area with increasing age may help explain the susceptibility of individuals to SCFE in adolescence: in a stable SCFE, the physis rotates on the tubercle; however, in an unstable SCFE, the tubercle dislodges, leading to more substantial displacement of the capital femoral epiphysis and the lateral epiphyseal vessels, risking osteonecrosis.

Idiopathic intracranial hypertension following spinal deformity surgery in children

Idiopathic intracranial hypertension (IIH) after pediatric spinal deformity surgery has not been previously reported. The authors conducted a retrospective analysis of more than 1500 pediatric spinal surgeries performed between 1992 and 2011. From their analysis, they report on 3 adolescent patients who underwent uncomplicated segmental spinal instrumentation for pediatric spinal deformity correction and subsequently developed features of IIH. The common variables in these 3 patients were adolescent age, spinal deformity, being overweight, symptom onset within 2 weeks postoperatively, significant estimated blood loss, and intraoperative use of ε-aminocaproic acid (antifibrinolytic) injection. The authors postulate that the development of IIH could be the result of venous outflow obstruction due to derangement of the epidural venous plexus during surgery. The use of ε-aminocaproic acid could potentially have the risk of causing IIH, probably mediated through hyperfibrinogenemia, although there have not been published cases in the neurosurgical, orthopedic, cardiac, or general surgical literature. Idiopathic intracranial hypertension after spinal deformity correction is a condition that should be recognized by neurosurgeons and orthopedic surgeons, because appropriate intervention with early medical therapy can lead to a satisfactory clinical outcome.

Salter osteotomy in Legg-Calvé-Perthes disease

BACKGROUND

Femoral head containment in Legg-Calvé-Perthes disease (LCPD) can be either surgical or nonsurgical. The Salter or innominate osteotomy is a common method of surgical containment. This is a review of the technique and results of this osteotomy in LCPD.

METHODS

The operative technique is relatively simple but requires considerable experience to perform correctly. It can be used alone or in combination with a proximal femoral varus osteotomy. The indications for a Salter osteotomy are essentially the same as in any form of containment treatment in LCPD. This includes: age at clinical onset of 6 to 10 years (perhaps, 5 y in female), more than one-half capital femoral epiphyseal involvement (Catterall groups III or IV, Salter-Thompson group B, and lateral pillar groups B, B/C, and C), and a good range of hip motion before surgery. The osteotomy alone is usually indicated for younger children with recent clinical onset and no femoral head deformity or subluxation. The combined procedure is better suited for older children and those with subluxation or a deformed femoral head.

RESULTS

Currently, the results of treatment are best determined at skeletal maturity using the Stulberg et al classification. When used alone, approximately 90% to 95% of the involved hips will have achieved a Stulberg et al class I, II, or III result. When combined with a proximal femoral varus osteotomy, the results are somewhat less because of the older age at onset and/or the presence of a deformed hip.

CONCLUSIONS

The Salter osteotomy in LCPD is an effective method of surgical treatment that can alter the natural history of the disease process. The main advantage of this osteotomy is its effect on femoral head remodeling during remaining growth.

Containment methods for treatment of Legg-Calvé-Perthes disease

The objective of containment treatment in Perthes disease is to hold the femoral head in the acetabulum during the period of "biologic plasticity" while necrotic bone is resorbed and living bone is restored through the process of "creeping substitution." This article identifies the various methods of containment and the technical aspects of each method. Choice of method depends on the experience of the surgeon and the psychosocial needs of the patient and family. Failure is more commonly a result of inappropriate patient selection for a particular method, delay in management, or technical errors rather than to the method that was selected.

Complications of growing-rod treatment for early-onset scoliosis: analysis of one hundred and forty patients

BACKGROUND

Previous reports have indicated high complication rates associated with non-fusion surgery in patients with early-onset scoliosis. This study was performed to evaluate the clinical and radiographic complications associated with growing-rod treatment.

METHODS

Data from the multicenter Growing Spine Study Group database were evaluated. Inclusion criteria were growing-rod treatment for early-onset scoliosis and a minimum of two years of follow-up. Patients were divided into treatment groups according to rod type (single or dual) and rod location (subcutaneous or submuscular). Complications were categorized as wound, implant, alignment, and general (surgical or medical). Surgical procedures were classified as planned and unplanned.

RESULTS

Between 1987 and 2005, 140 patients met the inclusion criteria and underwent a total of 897 growing-rod procedures. The mean age at the initial surgery was six years, and the mean duration of follow-up was five years. Eighty-one (58%) of the 140 patients had a minimum of one complication. Nineteen (27%) of the seventy-one patients with a single rod had unplanned procedures because of implant complications, compared with seven (10%) of the sixty-nine patients with dual rods (p ≤ 0.05). Thirteen (26%) of the fifty-one patients with subcutaneous rod placement had wound complications compared with nine of the eighty-eight patients (10%) with submuscular rod placement (p ≤ 0.05). The patients with subcutaneous dual rods had more wound complications, more prominent implants, and more unplanned surgical procedures than did those with submuscular dual rods (p ≤ 0.05). The risk of complications occurring during the treatment period decreased by 13% for each year of increased patient age at the initiation of treatment. The complication risk increased by 24% for each additional surgical procedure performed.

CONCLUSIONS

Regardless of treatment modality, the management of early-onset scoliosis is prolonged; therefore, complications are frequent and should be expected. Complications can be reduced by delaying initial implantation of the growing rods if possible, using dual rods, and limiting the number of lengthening procedures. Submuscular placement reduces wound and implant-prominence complications and reduces the number of unplanned operations.

Growing rods for infantile scoliosis in Marfan syndrome

STUDY DESIGN

Retrospective review.

OBJECTIVE

To evaluate the effectiveness of a new growing rod technique in controlling infantile scoliosis in patients with Marfan syndrome.

SUMMARY OF BACKGROUND DATA

Infantile scoliosis in patients with Marfan syndrome is nearly always progressive and poorly controlled by bracing, yet previous studies have shown poor results with first-generation extensible spinal rod techniques.

METHODS

Ten patients with Marfan syndrome and scoliosis developing before 3 years of age were treated with growing rods (3 single, 7 dual). Mean age at initial surgery was 5.3 years (SD, 2.7 years). Before surgery, the mean curve was 77.2 degrees (SD, 15.6 degrees ) and the mean thoracolumbar kyphosis was 56 degrees (SD, 21 degrees ). Patients on warfarin sodium were lengthened at yearly intervals; others, more frequently. Mean follow-up was 87 months (SD, 30.5 months).

RESULTS

Mean curve correction was 51% (SD, 23%) overall, 31% (SD, 23%) for single rods, and 60% (SD, 19%) for dual rods. Mean coronal and sagittal imbalance improved from 56 to 18 mm and from 31 to 21 mm, respectively. The mean length obtained was 11.5 cm (SD, 3.6 cm) overall and 11.2 cm (SD, 3.60 cm) for the 5 patients with final fusion. Complications included 2 rod breakages and 3 intraoperative dural leaks. There was 1 anchor dislodgement and no postoperative dural leak. No patient developed clinically noteworthy junctional kyphosis. One patient died of unrelated causes 3 months after surgery.

CONCLUSION

As life expectancy improves for patients with neonatal Marfan syndrome, spinal deformity becomes an important issue. Extensible spinal growing rods are an effective solution to the problem. Dual rods appear to be more corrective than single rods. Substantial spinal length can be obtained to minimize trunk disproportion. Growing rods may help prevent large infantile curves from becoming severe in Marfan syndrome, allowing definitive spinal fusion closer to skeletal maturity.

Tibialis anterior tendon transfer after clubfoot surgery

Recurrent dynamic and structural deformities following clubfoot surgery are commonly due to residual muscle imbalance from a strong tibialis anterior muscle and weak antagonists. We asked whether subcutaneous tibialis anterior tendon transfer effectively treated recurrent deformities following clubfoot surgery and whether the presence of structural deformities influenced the outcome. The patients were divided into two groups: Group I, dynamic supination deformity only (51 patients, 76 feet); and Group II, dynamic supination with other structural deformities (44 patients, 61 feet). The mean age at surgery was 4.3 years (range, 1.4-10.7 years); the minimum followup was 2 years (mean, 5.2 years; range, 2-12.5 years) for both groups. The results were graded according to our subjective rating system of restoration of muscle balance: good, restoration of muscle balance; fair, partial restoration of muscle balance; and poor, no improvement. The two groups had similar outcomes: in Group I, there were 65 good (87%), 11 fair (13%), and no poor results and in Group II, there were 54 good (88%), seven fair (12%), and no poor results. Our data suggest the tibialis anterior tendon transfer restores muscle balance in recurrent clubfeet; we observed no recurrences. This transfer improves function and may prevent secondary osseous changes. We believe the muscle imbalance supports, at least in part, the neuromuscular etiological aspects of congenital clubfeet.

LEVEL OF EVIDENCE

Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

A randomized prospective study of music therapy for reducing anxiety during cast room procedures

BACKGROUND

Cast room procedures, such as cast application and removal, pin removal, and suture removal can cause significant anxiety in young children. The use of music therapy in the cast room to decrease anxiety has not been previously reported.

METHODS

We performed a randomized, prospective study of soft lullaby music compared with no music in 69 children 10 years or younger undergoing cast room procedures. Heart rates (beats per minute) were recorded in the waiting room and cast room using a pulse oximeter.

RESULTS

A total of 28 children were randomized to music and 41 children to no music. The mean rise in heart rate between the waiting room and entering the cast room was -2.7 beats/min in the music group and 4.7 beats/min in the no music group (P = 0.001). The mean difference in heart rate between the waiting room and during the procedure was 15.3 beats/min in the music group and 22.5 beats/min in the no music group (P = 0.05). There were 7 patients in the no music group with heart rate increases of greater than 40 beats/min. No patient in the music group had an increase of this magnitude.

CONCLUSIONS

Playing soft music in the cast room is a simple and inexpensive option for decreasing anxiety in young children during cast room procedures.

LEVEL OF EVIDENCE

Randomized Clinical Trial, Level II.

Inclusion and assessment criteria for conservative scoliosis treatment

The efficacy of brace or conservative treatment in adolescent idiopathic scoliosis is controversial due to variations in inclusion and assessment criteria. This makes the interpretation of brace studies and their comparisons difficult. The Scoliosis Research Society recently introduced new standardized inclusion and assessment criteria for future brace studies. The inclusion criteria include: age 10 years or older at initiation of bracing, Risser sign 0-2, primary curve magnitude 25 to 40 degrees, no prior treatment, and females either premenarche or less than one year post-menarche. The assessment criteria include: percentage of patients with < or = 5 degree curve progression and percentage of patients with > or = 6 degree curve progression at skeletal maturity, percentage of patients who had surgery or recommended before skeletal maturity, percentage of patients with curves exceeding 45 degrees at maturity, and a minimum of 2 years follow-up beyond skeletal maturity for those patients felt to have been successfully treated. All patients treated irregardless of compliance are to be included in the results (intent to treat). The use of these criteria should assist in the determination of the effectiveness of brace treatment, as well as accurate comparison between patient groups and different braces.

Patient care, professionalism, and relations with industry

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Unique case of polydactyly and a new classification system

Polydactyly of the hands or feet is a common birth deformity. We recently encountered a female infant with a case of a crossed type 1 polydactyly with a mixed polydactyly of the feet. A mixed and crossed polydactyly is a rare finding with only one other reported case. This is the first report of crossed and mixed polydactyly of the feet presenting with 7 complete toes on each foot without syndactyly. In addition to a discussion of the treatment, this case has lead us to propose a more complete and less confusing classification system.

Growing rod techniques in early-onset scoliosis

BACKGROUND

The surgical treatment of severe early-onset scoliosis (EOS) is controversial. Obtaining and maintaining deformity correction, achieving adequate spinal growth, allowing lung development, and the high complication rate make surgical treatment very challenging. Growing rods are the most common method of management.

METHODS

Currently, there are 3 systems being used for the surgical treatment of EOS: single growing rod, dual growing rods, and the vertical expandable titanium prosthetic rib implant. Each system has its advantages and disadvantages. These are presented and discussed in this review.

RESULTS

The current clinical and radiographic results indicate that all 3 techniques can be effective in the surgical management of EOS. Vertical expandable prosthetic titanium rib (VEPTR), which is not considered a true growing rod system, is particularly effective in congenital scoliosis with fused ribs.

CONCLUSIONS

The current expandable spinal implant systems appear effective in controlling progressive EOS, allowing for spinal growth and improving lung development. All have a moderate complication rate, especially rod breakage and hook displacement.

A comparison of the thoracolumbosacral orthoses and providence orthosis in the treatment of adolescent idiopathic scoliosis: results using the new SRS inclusion and assessment criteria for bracing studies

This is a retrospective cohort study comparing the effectiveness of the thoracolumbosacral orthosis (TLSO) and the Providence orthosis in the treatment of adolescent idiopathic scoliosis (AIS) using the new Scoliosis Research Society (SRS) Committee on Bracing and Nonoperative Management inclusion and assessment criteria for bracing studies. These new criteria will make future studies comparable and more valid and accurate.

METHODS

We have used a custom TLSO (duration, 22 hours/day) and the Providence orthosis (duration, 8-10 hours/night) to control progressive AIS curves. Only 83 of 160 patients met the new SRS inclusion criteria: age of 10 years and older at initiation of bracing; initial curve of 25 to 40 degrees; Risser sign 0 to 2; female; premenarcheal or less than 1 year past menarche; and no previous treatment. There were 48 patients in the TLSO group and 35 in the Providence group. The new SRS assessment criteria of effectiveness included the percentage of patients who had 5 degrees or less and 6 degrees or more of curve progression at maturity, the percentage of patients whose curve progressed beyond 45 degrees, the percentage of patients who had surgery recommended or undertaken, and a minimum of 2 years of follow-up beyond maturity in those patients who were thought to have been successfully treated. All patients are evaluated regardless of compliance (intent to treat).

RESULTS

There were no significant differences in age at brace initiation, initial primary curve magnitude, sex, or initial Risser sign between the 2 groups. In the TLSO group, only 7 patients (15%) did not progress (<or=5 degrees), whereas 41 patients (85%) progressed by 6 degrees or more, including the 30 patients whose curves exceeded 45 degrees. Thirty-eight patients (79%) required surgery. In the Providence group, 11 patients (31%) did not progress, whereas 24 patients (69%) progressed by 6 degrees or more, including 15 patients whose curves exceeded 45 degrees. Twenty-one patients (60%) required surgery. However, when the initial curve at initiation of bracing was 25 to 35 degrees, the results improved. Five (15%) of 34 patients in the TLSO group and 10 (42%) of 24 patients in the Providence group did not progress, whereas 29 patients (85%) and 14 patients (58%), respectively, progressed by 6 degrees or more, and 26 patients (76%) and 11 patients (46%), respectively, required surgery.

CONCLUSIONS

Using the new SRS bracing criteria, the Providence orthosis was more effective for avoiding surgery and preventing curve progression when the primary initial curves at bracing was 35 degrees or less. However, the overall success of orthotic management for AIS in both groups was inferior to previous studies. Our results raise the question of the effectiveness of orthotic management in AIS and support the need for a multicenter, randomized study using these new criteria.