While spinal fusion is an approach to treatment, it may not be successful and may limit growth (lengthening) of the spine.

The vertical expandable prosthetic titanium rib device is a curved rod placed vertically in the chest that helps to stabilize and shape the thoracic cavity. It is positioned either between ribs or between the ribs and either the spine or pelvis. The vertical expandable prosthetic titanium rib may be described as “rib-based” growth-sparing instrumentation, which is compared with “spine-based” growing rods for Cobb angle correction. The vertical expandable prosthetic titanium rib device is designed to be expanded every 4 to 6 months as growth occurs and to be replaced if necessary. Some patients require multiple devices.

Regulatory Status

The VEPTR™ (DePuy Synthes Spine, Raynham, MA) was initially cleared for marketing by the U.S. Food and Drug Administration (FDA) through a humanitarian device exemption for the treatment of thoracic insufficiency syndrome in skeletally immature patients.^1, In 2014, the VEPTR™ was cleared for marketing by the FDA through the 510(k) process. The VEPTR™ and VEPTR II™ devices are indicated for skeletally immature patients with severe progressive spinal deformities and/or 3-dimensional deformity of the thorax associated with or at risk of thoracic insufficiency syndrome. This would include patients with progressive congenital, neuromuscular, idiopathic, or syndromic scoliosis.

To identify potential thoracic insufficiency syndrome patients, the following categories are used:

• Flail chest syndrome
• Rib fusion and scoliosis
• Hypoplastic thorax syndrome, including
  • Jeune syndrome
  • Achondroplasia
  • Jarcho-Levin syndrome
  • Ellis-van Creveld syndrome.

Related Policies

• Interventions for Progressive Scoliosis (Policy #130 in the Treatment Section)

II. Use of the vertical expandable prosthetic titanium rib for all other conditions, including but not limited to the treatment of scoliosis in members without thoracic insufficiency, is considered investigational.

Policy Guidelines: (Information to guide medical necessity determination based on the criteria contained within the policy statements above.)

Due to complexity of thoracoplasty and the young age of the patient population undergoing such a procedure, implantation of the vertical expandable prosthetic titanium rib (VEPTR®) should be performed in specialized centers. Preoperative evaluation should require input from a pediatric orthopedist, a pulmonologist, and a thoracic surgeon. In addition, preoperative evaluation should require (when possible) a test for positive nutritional, cardiac, and pulmonary function.


Medicare Coverage:
There is no National Coverage Determination (NCD) or Local Coverage Determination (LCD) for jurisdiction JL for this service. Therefore, Medicare Advantage Products will follow the Horizon BCBSNJ Medical Policy.


[RATIONALE: This policy was created in 2011 and has been updated regularly with searches of the PubMed database. The most recent literature update was performed through February 11, 2020.

Evidence reviews assess the clinical evidence to determine whether the use of a technology improves the net health outcome. Broadly defined, health outcomes are length of life, quality of life, and ability to function, including benefits and harms. Every clinical condition has specific outcomes that are important to patients and to managing the course of that condition. Validated outcome measures are necessary to ascertain whether a condition improves or worsens; and whether the magnitude of that change is clinically significant. The net health outcome is a balance of benefits and harms.

To assess whether the evidence is sufficient to draw conclusions about the net health outcome of a technology, 2 domains are examined: the relevance and the quality and credibility. To be relevant, studies must represent one or more intended clinical use of the technology in the intended population and compare an effective and appropriate alternative at a comparable intensity. For some conditions, the alternative will be supportive care or surveillance. The quality and credibility of the evidence depend on study design and conduct, minimizing bias and confounding that can generate incorrect findings. The randomized controlled trial is preferred to assess efficacy; however, in some circumstances, nonrandomized studies may be adequate. Randomized controlled trials are rarely large enough or long enough to capture less common adverse events and long-term effects. Other types of studies can be used for these purposes and to assess generalizability to broader clinical populations and settings of clinical practice.

Thoracic Insufficiency Syndrome
Clinical Context and Therapy Purpose

Thoracic insufficiency syndrome is the inability of the thorax to support normal respiration or lung growth.^2,The condition results from serious defects affecting the ribs or chest wall (eg, severe scoliosis with rib absence or rib fusion) and various hypoplastic thorax syndromes (eg, Jeune syndrome, Jarcho-Levin syndrome). Spine, chest, and lung growth are interdependent.^3,While the coexistence of chest wall and spinal deformity is well-documented, this effect on lung growth is not completely understood.

Progressive thoracic insufficiency syndrome includes respiratory insufficiency, loss of chest wall mobility, worsening 3-dimensional thoracic deformity, and/or worsening pulmonary function tests. As a child grows, progressive thoracic deformity and rotation toward the concave side occurs with worsening respiratory compromise. This progression is often accompanied by a need for supplemental oxygen and can require mechanical ventilation.

The purpose of the vertical expandable prosthetic titanium rib in patients who have progressive thoracic insufficiency syndrome is to provide a treatment option that is an alternative to or an improvement on existing therapies.

The question addressed in this policy is: Does the vertical expandable prosthetic titanium rib improve net health outcomes in patients who have progressive thoracic insufficiency syndrome?

The following PICO was used to select literature to inform this policy.

Patients

The relevant population of interest is children who have progressive thoracic insufficiency syndrome.

Interventions

The therapy being considered is the vertical expandable prosthetic titanium rib. The vertical expandable prosthetic titanium rib device is a curved rod placed vertically in the chest that helps to stabilize and shape the thoracic cavity. It is positioned either between ribs or between the ribs and either the spine or pelvis. The vertical expandable prosthetic titanium rib device is designed to be expanded every 4 to 6 months as growth occurs and to be replaced if necessary. Some patients require multiple devices.

Implanting the vertical expandable prosthetic titanium rib requires inpatient surgery conducted by a surgeon trained in the procedure; recovery requires several days to a week of hospitalization.

Comparators

For progressive thoracic insufficiency syndrome, relevant comparators include respiratory supportive care, which is administered by physicians and respiratory therapists, generally in an outpatient clinical setting.

Outcomes

The general outcomes of interest are symptoms, morbid events, functional outcomes, treatment-related mortality, and treatment-related morbidity. Based upon existing literature, follow-up of 2-5 years is recommended.

Study Selection Criteria

Methodologically credible studies were selected using the following principles:

1. To assess efficacy outcomes, comparative controlled prospective trials were sought, with a preference for RCTs.
2. In the absence of such trials, comparative observational studies were sought, with a preference for prospective studies.
3. To assess long-term outcomes and adverse events, single-arm studies that capture longer periods of follow-up and/or larger populations were sought.
4. Studies with duplicative or overlapping populations were excluded.

Data submitted to the U.S. Food and Drug Administration (FDA) on thoracic insufficiency syndrome include an initial feasibility study involving 33 patients and a subsequent prospective study of 224 patients (214 with baseline data) at 7 study sites.^1, Of these, 94 had rib fusion, 93 had hypoplastic thoracic syndrome, 46 had progressive scoliosis, and 14 had flail chest as a cause of their thoracic insufficiency syndrome. Three- and 5-year follow-up rates for the multicenter study were approximately 95%. Of the 247 patients enrolled in either study, 12 (4.8%) patients died, and 2 withdrew. None of the deaths, as determined by investigators, were related to the vertical expandable prosthetic titanium rib. Because standard pulmonary function testing was not possible for most of this population, an assisted ventilatory rating was used to assess impact on respiratory status. The assisted ventilatory rating ranged from 0 (unassisted breathing on room air) to 4 (full-time ventilatory support). In the multicenter prospective study, the assisted ventilatory rating outcome improved or stabilized for 93% of the patients. Data were not reported for the number of patients who were no longer dependent on a ventilator.

Campbell (2004), who developed the vertical expandable prosthetic titanium rib, and colleagues reported on 27 patients who had surgery for thoracic insufficiency syndrome and at least 2 years of follow-up data; this series was based on 41 patients treated between 1990 and the study reporting.^4, Entry criteria for this study were acceptance by pediatric general surgeon, pediatric pulmonologist, and a pediatric orthopedist; age 6 months to skeletal maturity; progressive thoracic insufficiency syndrome; more than 10% reduction in height of the concave hemithorax; and 3 or more anomalous vertebrae, with 3 or more fused ribs at the apex of the deformity. Patients were followed for an average of 3.2 years (range, 2-12 years). Before surgery, the mean annual rate of progression was 15° per year (range, 2°-50° per year). Following surgery, the Cobb angle (of scoliosis) improved from 74° to a final value of 49°. Spine growth was at a rate of 0.8 cm per year. (Normal spinal growth is 0.6 cm/year for ages 5-10 years.) The final forced vital capacity (FVC) was 49% of predicted value in the 19 children who could complete pulmonary function tests. Preoperatively, one patient required continuous positive airway pressure, and another needed supplemental oxygen for ventilatory support at final follow-up.

Flynn et al (2013), reported an average 40.7 month follow-up (range, 25-78 months) in 24 children with nonsyndromic congenital scoliosis.^5, Twenty-three (95.8%) children had associated rib fusions, and the average age at surgery was 3.3 years (range, 0.7-12.5 years). With a mean of 5 expansion surgeries per patient (range, 1-10), the mean Cobb angle improved by 8.9° and mean thoracic height improved by 3.41 cm. Eight (33%) patients had a total of 16 adverse events, all of which required surgery.

Gadepalli et al (2011) examined growth and pulmonary function in 26 children who received a vertical expandable prosthetic titanium rib between 2006 and 2010.^6,In this case series, the children underwent 29 insertions and 57 expansions, with an average of 3 surgeries per child. Each procedure required an average 0.97 days in the intensive care unit and 4.41 days in the hospital. The mean Cobb angle improved by 29%, from 64.7° preoperatively to 46.1° postoperatively. Lung volumes measured by yearly thoracic computed tomography scans were similar when corrected for age. Pulmonary function tests were performed every 6 months in patients (n=12) who were not ventilator-dependent and could cooperate with the procedure. Pulmonary function tests showed no significant change from baseline to follow-up in percent predicted values for forced expiratory volume in 1 second (54.6 L vs. 51.8 L), forced vital capacity (FVC) (58.1 L vs. 55.9 L), or residual volume (145.3 L vs. 105.6 L), all respectively. Reoperation was required for 14 complications, 4 for chest tube placement (pneumothorax), 1 for seroma drainage, 6 for hardware removal (for infection), and 3 for hardware repositioning (for dislodgement). Another 22 complications were treated nonoperatively.

Emans et al (2005) reported results for patients with thoracic insufficiency syndrome who underwent the procedure at a single children’s hospital from 1999 to 2005.^7, Thirty-one patients with fused ribs and thoracic insufficiency syndrome were treated; 4 patients had prior spinal arthrodesis with continued progression of deformity. Before surgery, all patients showed progressive spinal deformity, progressive chest deformity, or progressive hemithoracic constriction. The mean age was 4.2 years, and mean follow-up was 2.6 years (range, 0.5-5.4 years). A 3-member team selected patients for surgery, and cardiac function was evaluated preoperatively. Lengthening of the vertical expandable prosthetic titanium rib was planned for every 4 to 6 months but often was longer due to intercurrent illness or difficulty with travel. The mean number of device lengthenings was 3.5 (range, 0-10). Six patients had device exchanges for growth. In 30 patients, spinal deformity was controlled, and growth continued (1.2 cm/y) in the thoracic spine during treatment at rates similar to normal children. In this study, final forced vital capacity (FVC) was 73.5% of predicted levels. Prior to the procedure, 2 patients were on ventilators and 3 patients required oxygen; at final follow-up, 1 patient required oxygen. Lung volume (measured by computed tomography scan) in the operated lung increased from 157 cm³ preoperatively to 326 cm³ at the final follow-up visit.

Motoyama et al (2006) from a children’s hospital reported on 10 patients with thoracic insufficiency syndrome.^8, Using a special portable pulmonary function test device, they reported on lung function in 10 children who had a vertical expandable prosthetic titanium rib. Median age was 4.3 years (range, 1.8-9.8 years) at first test, and patients were followed an average of 22 months (range, 7-33 months). At baseline, FVC showed a moderate-to-severe decrease (69% of predicted), indicating the presence of significant restrictive lung defect. FVC increased significantly over time, with an average rate of 26.8% per year, similar to that of healthy children of comparative ages. In terms of percent predicted values, FVC did not change significantly between the baseline and last test (70.3%), indicating that, in most children studied, lung growth kept pace with body growth.

Waldhausen at al (2007) published a series of 22 patients from another children’s hospital.^9, Seven (19%) of the 36 the vertical expandable prosthetic titanium rib units placed required revision and 10 of 22 children reported better activity levels while 2 of 22 children reported better respiratory function.

Other series have discussed weight gain after use of vertical expandable prosthetic titanium rib in thoracic insufficiency syndrome^10, or early changes in pulmonary function.^11,

Section Summary: Thoracic Insufficiency Syndrome

The evidence evaluating use of vertical expandable prosthetic titanium rib thoracoplasty to treat children with progressive thoracic insufficiency syndrome due to rib and/or chest wall defects consists of a few case series. Thoracic insufficiency syndrome occurs in a limited patient population. For example, the Boston Center reported results on 31 children treated from 1999 to 2005. The natural history of progressive thoracic insufficiency syndrome is worsening pulmonary function and pulmonary insufficiency. Results from the case series reported by different specialty centers have demonstrated improvement and/or stabilization in key measures with use of the vertical expandable prosthetic titanium rib in progressive thoracic insufficiency syndrome. This improvement has been noted in measures related to thoracic structure (eg, Cobb angle for those with scoliosis), growth of the thoracic spine and lung volumes, and stable or improved ventilatory status. While pulmonary function testing is difficult to track in patients suffering with thoracic insufficiency syndrome, a study has demonstrated an age-specific increase in FVC; further still, that same study reported a final FVC in the range of 50% to 70% of predicted value. Given the usual disease course of worsening thoracic volume and ventilatory status, the stabilization and/or improvement in the clinical measures outlined above would be highly unlikely if not for the intervention. Taken together, these outcomes demonstrate the positive impact of using the vertical expandable prosthetic titanium rib technology.

Scoliosis Without Thoracic Insufficiency Syndrome
Clinical Context and Therapy Purpose

The purpose of the vertical expandable prosthetic titanium rib in patients who have early-onset scoliosis without thoracic insufficiency syndrome is to provide a treatment option that is an alternative to or an improvement on existing therapies.

The question addressed in this policy is: Does vertical expandable prosthetic titanium rib improve net health outcomes in patients who have scoliosis without thoracic insufficiency syndrome?

The following PICO was used to select literature to inform this policy.

Patients

The relevant population of interest is young children with early-onset scoliosis without thoracic insufficiency syndrome.

Interventions

The therapy being considered is the vertical expandable prosthetic titanium rib. The vertical expandable prosthetic titanium rib device is a curved rod placed vertically in the chest that helps to stabilize and shape the thoracic cavity. It is positioned either between ribs or between the ribs and either the spine or pelvis. The vertical expandable prosthetic titanium rib device is designed to be expanded every 4 to 6 months as growth occurs and to be replaced if necessary. Some patients require multiple devices.

Implanting the vertical expandable prosthetic titanium rib requires inpatient surgery conducted by a surgeon trained in the procedure; recovery requires several days to a week of hospitalization.

Comparators

For early onset scoliosis, relevant comparators include spinal fusion and bracing. Spinal fusion is an inpatient procedure performed by an orthopedic surgeon in a hospital setting. Bracing is managed by an orthopedist in an outpatient clinical setting.

Outcomes

The general outcomes of interest are symptoms, morbid events, functional outcomes, treatment-related mortality, and treatment-related morbidity. Based upon the limited literature available on vertical expandable prosthetic titanium rib for scoliosis without thoracic insufficiency syndrome, follow-up of at least 4 years is recommended.

Study Selection Criteria

Methodologically credible studies were selected using the principles described in the first indication.

White et al (2011) reported on the off-label use of spine-to-spine vertical expandable prosthetic titanium rib to treat spinal deformity in 14 children without chest wall abnormalities.^12, The indications for the dual spine-to-spine rods were absence of a primary chest wall deformity, progression of spinal deformity to a Cobb angle of greater than 50°, and migration of a previously placed proximal rib anchor or a prior non-vertical expandable prosthetic titanium rib growing rod to the point of loss of stable fixation. At final follow-up (24-48 months), there was an improvement in the Cobb angle from 74° to 57°, an increase in T1-S1 height from 260 to 296 mm, and no significant change in kyphosis. Complications occurred in 6 (43%) of 14 patients and included 3 rod fractures in 2 patients, 3 superficial infections, and 1 case of prominent hardware that threatened skin integrity. As noted by authors, while results were similar to those obtained with other growing rods, “the high complication rates, need for multiple procedures in growing children, and small relative gains in radiographic parameters still challenge proof of the efficacy of all such treatment methods.”

Farley et al (2014) used data from a prospective registry to compare treatment of congenital scoliosis using vertical expandable prosthetic titanium rib (n=22) with treatment using spinal fusion (n=27) and observation (n=184).^13, Function, pain, and mental health status were measured with the 22 item Scoliosis Research Society questionnaire. Compared with the observation group, the vertical expandable prosthetic titanium rib group had higher total and image scores at the second and third visits and higher function scores at the third and fourth visits. Interpretation of this study is limited due to confounding factors, including age at treatment, unknown comorbidities, and the rationale for treatment selection.

Section Summary: Scoliosis Without Thoracic Insufficiency Syndrome

The evidence evaluating use of vertical expandable prosthetic titanium rib thoracoplasty to treat young children with early-onset scoliosis without thoracic insufficiency syndrome consists of a few case series. The vertical expandable prosthetic titanium rib is being evaluated for curves greater than 45° in infants and juveniles without thoracic insufficiency. Similar to thoracic insufficiency syndrome, very limited data are available on the use of the vertical expandable prosthetic titanium rib for early-onset scoliosis without thoracic insufficiency; additionally, little is known about the disease progression of early-onset scoliosis, and therefore little is known regarding the risk-benefit trade-off of the vertical expandable prosthetic titanium rib surgery.

Adverse Events

Complications that occur with vertical expandable prosthetic titanium rib need to be considered by practitioners and families when discussing this procedure. The FDA review and the articles by Campbell et al (2004) and Emans et al (2005) have informed the summary on complications arising from vertical expandable prosthetic titanium rib. ^1,4,7, Up to 25% of patients may experience device migration, including rib erosion. Approximately 10% of patients had infection-related complications. Brachial plexus injury or thoracic outlet syndrome occurred in 1% to 7% of these series. Skin sloughing was reported in 4 (15%) patients in the study by Campbell. Waldhausen et al (2016), in a single-center series, reported on device-related complications in 22 of 65 patients treated for thoracic insufficiency syndrome over a 13-year period.^14,

Summary of Evidence

For individuals who have progressive thoracic insufficiency syndrome due to rib and/or chest wall defects in childhood who receive vertical expandable prosthetic titanium rib thoracoplasty, the evidence includes a few case series. Relevant outcomes are symptoms, morbid events, functional outcomes, and treatment-related mortality and morbidity. Thoracic insufficiency syndrome occurs in a limited patient population. For example, the Boston Center reported results on 31 children treated from 1999 to 2005. The natural history of progressive thoracic insufficiency syndrome is worsening pulmonary function and pulmonary insufficiency. Results from case series reported at different specialty centers have demonstrated improvement and/or stabilization in key measures with use of the vertical expandable prosthetic titanium rib in progressive thoracic insufficiency syndrome. This improvement has been noted in measures related to thoracic structure (eg, Cobb angle for those with scoliosis), growth of the thoracic spine and lung volumes, and stable or improved ventilatory status. While pulmonary function testing is difficult to track in patients suffering with thoracic insufficiency syndrome, a study has demonstrated an age-specific increase in forced vital capacity; further still, that same study reported a final forced vital capacity in the range of 50% to 70% of predicted value. Given the usual disease course of worsening thoracic volume and ventilatory status, the stabilization and/or improvement in the clinical measures outlined above would be highly unlikely if not for the intervention. Taken together, these outcomes demonstrate the positive impact of using the vertical expandable prosthetic titanium rib technology. The evidence is sufficient to determine that the technology results in a meaningful improvement in the net health outcome.

For individuals with early-onset scoliosis without thoracic insufficiency syndrome who receive vertical expandable prosthetic titanium rib thoracoplasty, the evidence includes a few case series. Relevant outcomes are symptoms, morbid events, functional outcomes, and treatment-related mortality and morbidity. The vertical expandable prosthetic titanium rib is being evaluated for curves greater than 45° in infants and juveniles without thoracic insufficiency. Similar to thoracic insufficiency syndrome, very limited data are available on the use of the vertical expandable prosthetic titanium rib for early-onset scoliosis without thoracic insufficiency; additionally, little is known about the disease progression of early-onset scoliosis, and therefore little is known regarding the risk-benefit trade-off of the vertical expandable prosthetic titanium rib surgery. The evidence is insufficient to determine the effects of the technology on health outcomes.

SUPPLEMENTAL INFORMATION
Practice Guidelines and Position Statements

No guidelines or statements were identified.

U.S. Preventive Services Task Force Recommendations

Not applicable.

Ongoing and Unpublished Clinical Trials

Some currently unpublished trials that might influence this policy are listed in Table 1.

Table 1. Summary of Key Trials

NCT No.	Trial Name	Planned Enrollment	Completion Date
Ongoing
NCT02241954	Vertical Expandable Prosthetic Titanium Rib (VEPTR) for Thoracic Insufficiency Syndrome	20	Jan 2024
NCT01672749	Evaluation of a Growth Guiding Construct vs. Standard Dual Growing Rods and vertical expandable prosthetic titanium rib (VEPTR) for the Treatment of Early Onset Scoliosis Patients: A Prospective Multi-center Cohort Study With a Matched Historical Control	51	Apr 2027
Unpublished
NCT00689533a	Vertical expandable prosthetic titanium rib (VEPTR) Implantation to Treat Children With Early Onset Scoliosis Without Rib Abnormalities: A Prospective Multicenter Study	250	Jan 2016 (unknown; updated 06/03/08)

NCT: national clinical trial.
^a Denotes industry-sponsored or cosponsored trial.]
________________________________________________________________________________________

Horizon BCBSNJ Medical Policy Development Process:

This Horizon BCBSNJ Medical Policy (the “Medical Policy”) has been developed by Horizon BCBSNJ’s Medical Policy Committee (the “Committee”) consistent with generally accepted standards of medical practice, and reflects Horizon BCBSNJ’s view of the subject health care services, supplies or procedures, and in what circumstances they are deemed to be medically necessary or experimental/ investigational in nature. This Medical Policy also considers whether and to what degree the subject health care services, supplies or procedures are clinically appropriate, in terms of type, frequency, extent, site and duration and if they are considered effective for the illnesses, injuries or diseases discussed. Where relevant, this Medical Policy considers whether the subject health care services, supplies or procedures are being requested primarily for the convenience of the covered person or the health care provider. It may also consider whether the services, supplies or procedures are more costly than an alternative service or sequence of services, supplies or procedures that are at least as likely to produce equivalent therapeutic or diagnostic results as to the diagnosis or treatment of the relevant illness, injury or disease. In reaching its conclusion regarding what it considers to be the generally accepted standards of medical practice, the Committee reviews and considers the following: all credible scientific evidence published in peer-reviewed medical literature generally recognized by the relevant medical community, physician and health care provider specialty society recommendations, the views of physicians and health care providers practicing in relevant clinical areas (including, but not limited to, the prevailing opinion within the appropriate specialty) and any other relevant factor as determined by applicable State and Federal laws and regulations.

___________________________________________________________________________________________________________________________

Index:
Vertical Expandable Prosthetic Titanium Rib
Prosthetic Titanium Rib
Titanium Rib
VEPTR

References:
1. Food and Drug Administration. Vertical Expandable Prosthetic Titanium Rib (VEPTR). 2004; https://www.accessdata.fda.gov/cdrh_docs/pdf14/k142587.pdf. Accessed March 4, 2020.

2. Campbell RM, Jr., Smith MD, Mayes TC, et al. The characteristics of thoracic insufficiency syndrome associated with fused ribs and congenital scoliosis. J Bone Joint Surg Am. Mar 2003;85-A(3):399-408. PMID 12637423

3. Campbell RM, Jr. VEPTR: past experience and the future of VEPTR principles. Eur Spine J. Mar 2013;22 Suppl 2:S106-117. PMID 23354777

4. Campbell RM, Jr., Smith MD, Mayes TC, et al. The effect of opening wedge thoracostomy on thoracic insufficiency syndrome associated with fused ribs and congenital scoliosis. J Bone Joint Surg Am. Aug 2004;86- A(8):1659-1674. PMID 15292413

5. Flynn JM, Emans JB, Smith JT, et al. VEPTR to treat nonsyndromic congenital scoliosis: a multicenter, mid-term follow-up study. J Pediatr Orthop. Oct-Nov 2013;33(7):679-684. PMID 23812154

6. Gadepalli SK, Hirschl RB, Tsai WC, et al. Vertical expandable prosthetic titanium rib device insertion: does it improve pulmonary function? J Pediatr Surg. Jan 2011;46(1):77-80. PMID 21238644

7. Emans JB, Caubet JF, Ordonez CL, et al. The treatment of spine and chest wall deformities with fused ribs by expansion thoracostomy and insertion of vertical expandable prosthetic titanium rib: growth of thoracic spine and improvement of lung volumes. Spine (Phila Pa 1976). Sep 1 2005;30(17 Suppl):S58-68. PMID 16138067

8. Motoyama EK, Deeney VF, Fine GF, et al. Effects on lung function of multiple expansion thoracoplasty in children with thoracic insufficiency syndrome: a longitudinal study. Spine (Phila Pa 1976). Feb 1 2006;31(3):284- 290. PMID 16449900

9. Waldhausen JH, Redding GJ, Song KM. Vertical expandable prosthetic titanium rib for thoracic insufficiency syndrome: a new method to treat an old problem. J Pediatr Surg. Jan 2007;42(1):76-80. PMID 17208544

10. Skaggs DL, Sankar WN, Albrektson J, et al. Weight gain following vertical expandable prosthetic titanium ribs surgery in children with thoracic insufficiency syndrome. Spine (Phila Pa 1976). Nov 1 2009;34(23):2530-2533. PMID 19927103

11. Mayer OH, Redding G. Early changes in pulmonary function after vertical expandable prosthetic titanium rib insertion in children with thoracic insufficiency syndrome. J Pediatr Orthop. Jan-Feb 2009;29(1):35-38. PMID 19098643

12. White KK, Song KM, Frost N, et al. VEPTR growing rods for early-onset neuromuscular scoliosis: feasible and effective. Clin Orthop Relat Res. May 2011;469(5):1335-1341. PMID 21213088

13. Farley FA, Li Y, Jong N, et al. Congenital scoliosis SRS-22 outcomes in children treated with observation, surgery, and VEPTR. Spine (Phila Pa 1976). Oct 15 2014;39(22):1868-1874. PMID 25099323

14. Waldhausen JH, Redding G, White K, et al. Complications in using the vertical expandable prosthetic titanium rib (VEPTR) in children. J Pediatr Surg. Nov 2016;51(11):1747-1750. PMID 27397045

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