Is spinal height gain associated with rod orientation and the use of cross-links in magnetically controlled growing rods in early-onset scoliosis?

Optimal orientation for magnetically controlled growing rods (MCGRs) is unclear. The objective of this study was to investigate associations of rod orientation with implant-related complications (IRCs) and spinal height gains. Using an international early-onset scoliosis (EOS) database, we retrospectively reviewed 57 patients treated with dual MCGRs from May 2013 to July 2015 with minimum 2-year follow-up. Outcomes of interest were IRCs and left/right rod length gains and thoracic (T1-T12) and spinal (T1-S1) heights. We compared patients with two rods lengthened in the cephalad ( standard; n  = 18) versus opposite ( offset; n  = 39) directions. Groups did not differ in age, sex, BMI, duration of follow-up, EOS cause, ambulatory status, primary curve magnitude, baseline thoracic height, or number of distractions/year. We compared patients whose constructs used ≥1 cross-link (CL group; n  = 22) versus no CLs (NCL group; n  = 35), analyzing thoracic height gains per distraction ( α  = 0.05). Offset and standard groups did not differ in left or right rod length gains overall or per year or in thoracic or spinal height gain. Per distraction, the CL and NCL groups did not differ significantly in left or right rod length or thoracic or spinal height gain. Complications did not differ significantly between rod orientation groups or between CL groups. MCGR orientation and presence of cross-links were not associated with differences in rod length gain, thoracic height, spinal height, or IRCs at 2-year follow-up. Surgeons should feel comfortable using either MCGR orientation. Level of evidence: 3, retrospective.

Treatment of Early-onset Scoliosis: Similar Outcomes Despite Different Etiologic Subtypes in Traditional Growing Rod Graduates.

BACKGROUND: It is unclear whether traditional growing rod (TGR) treatment outcomes vary by early-onset scoliosis (EOS) subtype. The goal of this study was to compare radiographic outcomes and complications of TGR treatment by EOS subtype. METHODS: We queried an international database of EOS patients from 20 centers to identify "graduates" who had (1) undergone primary TGR treatment from 1993 to 2014; (2) completed TGR treatment; and (3) had an uneventful clinical examination within 6 months after completion of TGR treatment with no anticipated further intervention. We included 202 patients in 4 etiologic subgroups: neuromuscular (n=65), syndromic (n=57), idiopathic (n=52), and congenital (n=28). Mean age at surgery was 7.1 years (range, 1.6 to 14.9 y); mean duration of follow-up was 8 years (range, 2 to 18.6 y). The groups did not differ by mean age, body mass index, sex, number of lengthenings, or duration of follow-up. The following preoperative differences were significant: (1) greater mean major curve in the neuromuscular versus idiopathic subgroup; (2) shorter spinal height (T1-S1) in the congenital versus idiopathic subgroup; and (3) smaller proportion of ambulatory patients in the neuromuscular subgroup versus all other subgroups. RESULTS: We found no significant differences among subgroups in mean major curve correction or changes in thoracic height (T1-T12), spinal height, or global kyphosis at any point. Rates of deep surgical site infection, implant-related complications, and neurological complications were not different among subgroups. The medical complication rate was significantly lower in the idiopathic group compared with the other groups. CONCLUSIONS: Major curve correction and spinal and thoracic height increases did not differ significantly at any point by EOS subtype. Rates of deep surgical site infection, implant-related complications, and neurological complications did not differ by subtype. Except for the lower rate of medical complications in the idiopathic group, our findings suggest that, after TGR treatment, patients can expect similar outcomes regardless of their EOS subtype. LEVEL OF EVIDENCE: Level III, therapeutic.

An initial effort to define an early onset scoliosis "graduate"-The Pediatric Spine Study Group experience.

PURPOSE: Increasingly, patients with early onset scoliosis (EOS) are completing a growth friendly surgical program followed by observation, removal of implants or a definitive spinal fusion. These patients are colloquially referred to as "graduates". A standardized definition of a graduate is needed for research and comparing the outcomes, family counseling, and a better understanding of the population. METHODS: A 15-question electronic survey was completed by 39 experienced pediatric spine surgeons to identify factors salient to the definition of a graduate of EOS surgical programs. A Delphi/Nominal group technique session with nine questions was then performed face-to-face with 21 members of the Pediatric Spine Study Group to discuss and refine the definition. A follow-up electronic survey was then distributed to these same 21 members to gain consensus on the final definition. RESULTS: From the initial survey, it was identified that a graduate did not require definitive spinal fusion after a growing program. From the Delphi session, it was determined that skeletal maturity was the most important factor in defining a graduate. A strictly defined minimum length of follow-up was not felt to be a prerequisite for qualification of graduation. After the final electronic version was distributed, > 80% of respondents agreed upon the final definition, thereby achieving consensus. CONCLUSION: The Pediatric Spine Study Group recommends adoption of the following definition: a "graduate" is a patient who has undergone any surgical program to treat early onset scoliosis, and has reached skeletal maturity and does not have a planned surgical intervention for EOS in the future. LEVEL OF EVIDENCE: V.

A high degree of variability exists in how "safety and efficacy" is defined and reported in growing rod surgery for early onset scoliosis: a systematic review.

Established criteria for reporting safety and efficacy have not yet been defined in growing rod surgery for early onset scoliosis. A systematic literature review revealed a high degree of variability in how authors stratified complications and patient outcomes as a means to define safety and efficacy for this challenging patient population. INTRODUCTION: Several publications have reported the safety and efficacy of traditional growing rods (TGR) and magnetically controlled growing rods (MCGR) using various parameters. Radiographic parameters are most commonly used to measure efficacy, while incidence and type of complications are used to assess safety. A systematic review of peer-reviewed articles was performed to identify whether a consensus exists in how safety and efficacy parameters are reported in EOS patients treated with TGR and MCGR. HYPOTHESIS: There is no consensus on the parameters used for reporting safety and efficacy in growing rod treatment for early onset scoliosis. STUDY DESIGN: Systematic literature review. METHODS: Four databases were searched on November 10, 2016 to identify all qualified peer-reviewed articles using specific keyword searches. All peer-reviewed articles published in English language reporting any data related to safety and efficacy of the TGR and/or MCGR surgical technique were included. Articles that met the inclusion criteria were scored by modified Downs and Black scoring system (J Epidemiol Community Health 52(6):377-384, 1998) for non-randomized studies. All reported safety and efficacy data were extracted and analyzed. RESULTS: Search of the databases resulted in 111 unique citations including: PubMed (50), Embase (68 with 21 duplicates), Web of Science (29 with 15 duplicates), and CINAHL (15; all duplicates). Fifty-six of 111 citations were excluded during the review of the titles and abstracts. In addition, 16 citations were excluded at the time of full manuscript review. The remaining 39 articles included 23 TGR (2007-2016) and 16 MCGR papers (2012-2016). The overall Downs and Black score was 63.9 for TGR papers vs. 64.0 for MCGR papers (p = 0.97). Efficacy measures were not consistently reported among the publications. The only consistently reported efficacy parameter in majority (> 90%) of papers was curve size. Complication reporting was highly variable. CONCLUSION: Major curve size was the only consistent parameter to report efficacy in peer-reviewed TGR and MCGR publications. Since complications were not consistently reported, assessing safety of either treatment was infeasible. Establishing standardized safety and efficacy parameters in growing rod surgery for EOS would improve the quality of future studies and makes comparison of different treatment modalities possible. Indeed, other clinically relevant parameters such as health-related quality of life, pulmonary function, nutritional status, and psychiatric and developmental health should also be considered to improve the future safety and efficacy reporting.

Preservation of Spine Motion in the Surgical Treatment of Adolescent Idiopathic Scoliosis Using an Innovative Apical Fusion Technique: A 2-Year Follow-Up Pilot Study.

BACKGROUND: This trial reports the 2-year and immediate postremoval clinical outcomes of a novel posterior apical short-segment (PASS) correction technique allowing for correction and stabilization of adolescent idiopathic scoliosis (AIS) with limited fusion. METHODS: Twenty-one consecutive female AIS patients were treated at 4 institutions with this novel technique. Arthrodesis was limited to the short apical curve after correction with translational and derotational forces applied to upper and lower instrumented levels. Instrumentation spanned fused and unfused segments with motion and flexibility of unfused segments maintained. The long concave rods were removed at maturity. Radiographic data collected included preoperative and postoperative data for up to 2 years as well as after long rod removal. RESULTS: All 21 patients are beyond 2 years postsurgery. Average age at surgery was 14.2 years (11-17 years). A mean of 10.5 ± 1 levels per patient were stabilized and 5.0 ± 0.5 levels (48%) were fused. Cobb angle improved from 56.1° ± 8.0° to 20.8° ± 7.8° (62.2% improvement) at 1 year and 20.9° ± 8.4°, (62.0% improvement) at 2 years postsurgery. In levels instrumented but not fused, motion was 26° ± 6° preoperatively compared to 10° ± 4° at 1 year postsurgery, demonstrating 38% maintenance of mobility in nonfused segments. There was no report of implant-related complications. CONCLUSIONS: PASS correction technique corrected the deformity profile in AIS patients with a lower implant density while sparing 52% of the instrumented levels from fusion through the 2-year follow-up.

Construct Levels to Anchored Levels Ratio and Rod Diameter Are Associated With Implant-Related Complications in Traditional Growing Rods.

INTRODUCTION: In addition to patient characteristics, consideration of length of construct to number of anchored levels ratio and rod diameter should be a part of preoperative planning to minimize implant-related complications (IRCs). IRCs including rod breakage, anchor dislodgement, and pullout are among the most common adverse events in traditional growing rods (TGRs). The current study hypothesized that anchor type and configuration are associated with IRC. METHODS: Patients with (1) age ≤10 years at surgery; (2) spine-based dual TGR; (3) minimum 2-year follow-up; and (4) available imaging. Cephalad and caudal foundations were grouped based on the number of instrumented levels and anchor type. All radiographs were reviewed. Based on the results, a "construct levels / anchored levels" (CL/AL) ratio was calculated, which is the number of levels spanned by instrumentation divided by the number of levels with bone-anchor fixation. Receiver operating characteristic curve was used to define the CL/AL threshold. RESULTS: 274 patients divided into patients with complications (IRC+, n = 140) and without complications (IRC-, n = 134) groups. Mean follow-up was 6.3 years (2.1-18.0 years). No significant differences in age, gender, body mass index, ambulatory status, etiology, primary curve size, T1-S1 height, coronal and sagittal balance, and rod material were observed between the two groups. Comparative analysis showed that connector type, presence and location of crosslinks, number of levels instrumented, number and type of anchors, presence of pelvic fixation, and mirroring of cephalad and caudal foundations were not different. However, maximum kyphosis and rod diameter were significantly different. The CL/AL ratio threshold was 3.5. Multivariate analysis of kyphosis, rod diameter, and CL/AL ratio showed a significant association with IRC (p < .05). DISCUSSION AND CONCLUSION: Although patient characteristics like kyphosis have been proven to be associated with instrumentation failure, it is a combination of characteristics that include rod diameter and CL/AL ratio that showed significant correlation with IRC. Validation of the CL/AL ratio is recommended.

Preliminary results of anterior lumbar interbody fusion, anterior column realignment for the treatment of sagittal malalignment.

OBJECTIVE Sagittal malalignment decreases patients' quality of life and may require surgical correction to achieve realignment goals. High-risk posterior-based osteotomy techniques are the current standard treatment for addressing sagittal malalignment. More recently, anterior lumbar interbody fusion, anterior column realignment (ALIF ACR) has been introduced as an alternative for correction of sagittal deformity. The objective of this paper was to report clinical and radiographic results for patients treated using the ALIF-ACR technique. METHODS A retrospective study of 39 patients treated with ALIF ACR was performed. Patient demographics, operative details, radiographic parameters, neurological assessments, outcome measures, and preoperative, postoperative, and mean 1-year follow-up complications were studied. RESULTS The patient population comprised 39 patients (27 females and 12 males) with a mean follow-up of 13.3 ± 4.7 months, mean age of 66.1 ± 11.6 years, and mean body mass index of 27.3 ± 6.2 kg/m2. The mean number of ALIF levels treated was 1.5 ± 0.5. Thirty-three (84.6%) of 39 patients underwent posterior spinal fixation and 33 (84.6%) of 39 underwent posterior column osteotomy, of which 20 (60.6%) of 33 procedures were performed at the level of the ALIF ACR. Pelvic tilt, sacral slope, and pelvic incidence were not statistically significantly different between the preoperative and postoperative periods and between the preoperative and 1-year follow-up periods (except for PT between the preoperative and 1-year follow-up, p = 0.018). Sagittal vertical axis, T-1 spinopelvic inclination, lumbar lordosis, pelvic incidence-lumbar lordosis mismatch, intradiscal angle, and motion segment angle all improved from the preoperative to postoperative period and the preoperative to 1-year follow-up (p < 0.05). The changes in motion segment angle and intradiscal angle achieved in the ALIF-ACR group without osteotomy compared with the ALIF-ACR group with osteotomy at the level of ACR were not statistically significant. Total visual analog score, Oswestry Disability Index, and Scoliosis Research Society-22 scores all improved from preoperative to postoperative and preoperative to 1-year follow-up. Fourteen patients (35.9%) experienced 26 complications (15 major and 11 minor). Eleven patients required reoperation. The most common complication was proximal junctional kyphosis (6/26 complications, 23%) followed by vertebral body/endplate fracture (3/26, 12%). CONCLUSIONS This study showed satisfactory radiographic and clinical outcomes at the 1-year follow-up. Proximal junctional kyphosis was the most common complication followed by fracture, complications that are commonly associated with sagittal realignment surgery and may not be mitigated by the anterior approach.

Generation of spectral clusters in a mixture of noble and Raman-active gases: publisher's note.

This note points out a correction to a typographical error in the published version of the article [Opt. Lett.41, 5543 (2016)OPLEDP0146-959210.1364/OL.41.005543].

Paper #37: A high degree of variability exists in how "safety and efficacy" is defined and reported in growing rod surgery for early-onset scoliosis: A systematic review.

Established criteria for reporting safety and efficacy have not yet been defined in growing rod surgery for early-onset scoliosis. A systematic literature review revealed a high degree of variability in how authors stratified complications and patient outcomes as a means to define safety and efficacy for this challenging patient population.

Rod fracture and lengthening intervals in traditional growing rods: is there a relationship?

PURPOSE: Is there any relationship between lengthening intervals and rod fracture in traditional growing rod (TGR) surgery? METHODS: A multicenter EOS database was queried for patients who had: (1) dual growing rods for EOS; (2) minimum 2-year follow-up; (3) a minimum of 2 lengthenings; and (4) revision surgery due to rod fracture. Of 138 patients who met the criteria: 56 patients experienced at least one-rod fracture (RF group) and 82 patients had no rod fractures (NRF group). In addition to each patient's lengthening intervals, demographics, construct details, and radiographic parameters were compared. RESULTS: RF and NRF patients had a mean pre-op age of 5.7 years (range 1.3-10.7) and 7.3 years (range 1.6-12.8), respectively (p < 0.001). There was no significant association between etiologies and rod fracture or between BMI and rod fracture (p = 0.979). There was no significant difference between lengthening intervals between the RF and NRF groups (p > 0.05). RF and NRF patients had statistically similar mean pre-op major curve size and max kyphosis (p = 0.279; p = 0.619, respectively). Stainless steel rods fractured more frequently compared with Titanium rods (SS 49.2 % vs. Ti 38 %; p = 0.004). Rod fracture occurred more in rods smaller than 4 mm (p = 0.011). CONCLUSIONS: Lengthening intervals were not statistically different in RF and NRF groups and there was no association between lengthening interval and rod fracture in TGR cases. It was shown that patients who had rod fracture were younger and were more likely to have SS rods with smaller than 4 mm diameter.

Implant Complications After Magnetically Controlled Growing Rods for Early Onset Scoliosis: A Multicenter Retrospective Review.

BACKGROUND: Traditional growing rods have a reported wound and implant complication rate as high as 58%. It is unclear whether the use of magnetically controlled growing rods (MCGR) will affect this rate. This study was performed to characterize surgical complications following MCGR in early onset scoliosis. METHODS: A multicenter retrospective review of MCGR cases was performed. Inclusion criteria were: (1) diagnosis of early onset scoliosis of any etiology; (2) 10 years and younger at time of index surgery; (3) preoperative major curve size >30 degrees; (4) preoperative thoracic spine height <22 cm. Complications were categorized as wound related and instrumentation related. Complications were also classified as early (<6 mo from index surgery) versus late (>6 mo). Distraction technique and interval of distraction was surgeon preference without standardization across sites. RESULTS: Fifty-four MCGR patients met inclusion criteria. There were 30 primary and 24 conversion procedures. Mean age at initial surgery was 7.3 years (range, 2.4 to 11 y), and mean duration of follow-up 19.4 months. Twenty-one (38.8%) of 54 patients had at least 1 complication. Fifteen (27.8%) had at least 1 revision surgery. Six (11.1%) had broken rods (2 to 4.5 and 4 to 5.5 mm rods); two 5.5 mm rods failed early (4 mo) and 4 late (mean=14.5 mo). Six (11.1%) patients experienced 1 episode of lack or loss of lengthening, of which 4 patients subsequently lengthened. Seven patients (13.0%) had either proximal or distal fixation-related complication at average of 8.4 months. Two patients (3.7%) had infections requiring incision and drainage; 1 early (2 wk) with wound drainage and 1 late (8 mo). The late case required removal of one of the dual rods. CONCLUSIONS: This study shows that compared with traditional growing rods, MCGR has a lower infection rate (3.7% vs. 11.1%). MCGR does not appear to prevent common implant-related complications such as rod or foundation failure. The long-term implication remains to be determined. LEVEL OF EVIDENCE: Level IV.

Generation of spectral clusters in a mixture of noble and Raman-active gases.

We report a novel scheme for the generation of dense clusters of Raman sidebands. The scheme uses a broadband-guiding hollow-core photonic crystal fiber (HC-PCF) filled with a mixture of H2, D2, and Xe for efficient interaction between the gas mixture and a green laser pump pulse (532 nm, 1 ns) of only 5 µJ of energy. This results in the generation from noise of more than 135 rovibrational Raman sidebands covering the visible spectral region with an average spacing of only 2.2 THz. Such a spectrally dense and compact fiber-based source is ideal for applications where closely spaced narrow-band laser lines with high spectral power density are required, such as in spectroscopy and sensing. When the HC-PCF is filled with a H2-D2 mixture, the Raman comb spans the spectral region from the deep UV (280 nm) to the near infrared (1000 nm).

Analysis of Segmental Mobility Following a Novel Posterior Apical Short-Segment Correction for Adolescent Idiopathic Scoliosis.

STUDY DESIGN: A prospective, nonrandomized, multicenter study. OBJECTIVES: The purpose of this study was to evaluate the amount of motion present at instrumented but unfused segments and at motion segments adjacent to the instrumentation following application of a new posterior apical short-segment correction technique for correcting adolescent idiopathic scoliosis (AIS). SUMMARY OF BACKGROUND DATA: High-density pedicle screw instrumentation and posterior arthrodesis of all instrumented levels is the most common surgical treatment for AIS stabilization. The consequence of long fusion is an abnormal load on adjacent levels with an increased risk of future adjacent segment degeneration. METHODS: This new system applied translational and derotational forces over a short apical segment. The short apical region was prepared for fusion while maintaining motion of unfused vertebral segments. Radiographic data were collected pre-operatively, at surgery, and at 3, 6, and 12 months after surgery. RESULTS: Twenty-one female patients, mean age of 14.2 years (10.6-16.9 years) with Lenke 1A/1B curves, were enrolled. The range of motion in the unfused instrumented segment was significantly higher than the apical fused segment (11 vs. 0.9, P < 0.001). The range of motion of unfused vertebral levels distal to the construct at one year did not differ significantly from their respective pre-op values. When the analysis was extended to understand the impact of lower instrumented vertebra (LIV) on motion of unfused segments distal to the construct, it appeared that (1) the change in motion from pre-op to 12 months post-op as a function of LIV is not statistically significant; and (2) The motion of the unfused distal vertebral segments at 12 months does not statistically increase with a lower LIV. CONCLUSION: Through one year, this novel technique achieved and maintained similar AIS correction to current posterior fusion techniques while maintaining the mobility of unfused motion segments with less implant density. LEVEL OF EVIDENCE: 4.

Do Longer Surgical Procedures Result in Greater Contamination of Surgeons' Hands?

BACKGROUND: A surgical site infection is a substantial cause of complications in patients. Different methods are being used to decrease surgical site infections; however, these infections still can cause complications, especially in patients undergoing longer operations (> 3 hours). There is evidence that the efficacy of the scrubbing material fades after 3 hours. However, we do not know the longevity of hand cleanliness after application of scrubbing materials in a long operation. It can be postulated that if the surgeon's scrubbed hands are recolonized after a certain time, they may serve as a progressive source of contamination during surgery. QUESTIONS/PURPOSES: We asked: (1) Is there a correlation between surgical duration and hand contamination at the end of surgery? (2) At what point during surgery does hand contamination reach or exceed prescrub levels? METHODS: Three spine surgeons using the same scrubbing technique and materials consisting of chlorhexidine gluconate 1% solution and ethyl alcohol 61% w/w were enrolled in our study. Between December 2014 and April 2015, spine procedures of 3 hours or more, which were the first case of the day, were selected for this study (20 cases). Cases in which glove changing occurred (perforations, reprepping, and redraping) or cultures obtained after scrubbing were positive (indicative of insufficient hand sanitization) were excluded (0% of cases). Twenty cases (100% enrollment) were analyzed. Surgeons' hands were swabbed with sterile cotton tip applicators and 5 mL sterile phosphate-buffered saline before hand scrubbing (prescrub), immediately after hand scrubbing (postscrub), and immediately after surgery (postoperative). Results were reported in colony-forming units per milliliter. The correlation between duration of surgery and hand recontamination was tested by regression analysis of time versus colony-forming units per milliliter. Receiver-operating characteristic curve tested the cutoff point, where recontamination occurred. RESULTS: With a longer duration of surgery, more colony-forming units are recovered from gloved hands at the end of surgery (R = 0.94, R(2) = 0.89, p = 0.005). The receiver-operating characteristic curve suggested that 5 hours is the cutoff point for hand recolonization. At 5 hours, contamination reached or exceeded prescrub levels (area under the curve, 0.66; 95% CI, 0.23-1.0), whereas before 5 hours, there was no contamination detected at the end of surgery. CONCLUSIONS: Our results show that duration of surgery correlates with hand recontamination and at 5 hours, recolonization of a surgeon's hands become detectable. Recolonization may have started even earlier than 5 hours. However, these levels are not detectable in the laboratory at earlier times. CLINICAL RELEVANCE: Based on this pilot study, rescrubbing is highly recommended before the fifth hour of an operation, ideally at some point between the fourth and fifth hours. FUTURE: We also recommend the surgical site infection rates in operations using rescrubbing should be compared with those from surgeries with just the conventional single-scrubbing technique, in a randomized controlled trial, to determine the effectiveness of this novel rescrubbing method.

Magnetically controlled Growing Rods for Early-onset Scoliosis: A Multicenter Study of 23 Cases With Minimum 2 years Follow-up.

STUDY DESIGN: Retrospective study. OBJECTIVE: To report 2-year clinical and radiographic results of patients treated with magnetically controlled growing rods (MCGR). SUMMARY OF BACKGROUND DATA: MCGR for early-onset scoliosis has been reported to provide adequate spinal growth and curve correction by eliminating surgical lengthening procedures. This study was designed to report the results of MCGR patients with 2-year follow-up. METHODS: A retrospective study of MCGR patients with the following inclusion criteria: (i) major curve size ≥30°, (ii) T1-T12 height <22 cm, (iii) <11-years old; all at the time of index surgery was performed. Of 54 patients enrolled, 23 had 2-year follow-up. Both primary and conversion patients were evaluated at baseline 6, 12, and 24 months. RESULTS: Mean preoperative age in the primary group was 6.6 ±â€Š2.6 years versus 8.3 ±â€Š2.2 years for the conversion group. A total of 41 adverse events occurred in 11 patients, of which 14 events were implant related. Major coronal curve magnitude improved from 61.3° to 34.3° from baseline to postoperation in primary cases and from 49.4° to 43.8° in conversion cases. Curve correction was maintained for 2 years in both groups. T1-S1 height improved from 252.7 to 288.9 mm in primary cases and was maintained for 2 years. However, conversion cases had some decline in T1- S1 height (270.3 at baseline to 294.4 mm post-MCGR and 290.2 mm at 2-year follow-up; mean loss of 4.2 mm (1.5%) from postoperation to 2 years, P > 0.05). CONCLUSION: This study showed satisfactory curve correction and growth is achieved among primary cases. T1-S1 height in conversion cases had a slight decline in 2 years. However, this decline was not statistically significant. LEVEL OF EVIDENCE: 3.