How do implants overlying the spine influence "The Law of Diminishing Returns" in early-onset scoliosis patients?

PURPOSE: The "law of diminishing returns" (LODR) in early-onset scoliosis (EOS) is well-known. We hypothesized that previously observed variations between constructs may be related to the lateral distance that each construct lies from the spine. We therefore sought to determine whether the curve magnitude improvement and spinal length gains for distraction-based constructs in EOS are positively correlated with the collinearity of the spine and the convex-sided implant on posteroanterior radiographs. METHODS: A prospectively-collected, multicenter EOS registry was queried for all patients who underwent non-fusion, distraction-based instrumentation surgery. Post-index radiographs were graded from 1 to 5 based on amount of overlap between the convex-sided rod and the apical vertebra. Grade 1: convex rod is lateral to convex-sided pedicle; Grade 2: overlaps the convex-sided pedicle; Grade 3: lies between pedicles; Grade 4: overlaps concave-sided pedicle; Grade 5: medial to concave-sided pedicle. ANOVA assessed the correlations between post-index overlap grade and change in (a) curve magnitude and (b) T1-T12 height. Multivariable regression modeling further assessed these associations. RESULTS: 284 patients met all selection criteria and were included. On ANOVA, post-index grade was associated with curve magnitude (p <0.001) and T1-12 height (p = 0.028) change. Better curve correction and height change were associated with higher grade. On regression modeling, curve correction (R = 0.574) and T1-T12 height change (R = 0.339) remained significantly associated with grade when controlling for time, anchor locations, age, underlying diagnosis, and pre-index curve magnitude. CONCLUSION: More apical overlap by the convex rod was associated with better spinal deformity control and improved height gain. LEVEL OF EVIDENCE III: Therapeutic.

Lengthening Behavior of Magnetically Controlled Growing Rods in Early-Onset Scoliosis: A Multicenter Study.

BACKGROUND: The "law of diminishing returns" is described for traditional growing rods. Magnetically controlled growing rods (MCGRs) have become a preferred implant for the surgical treatment of early-onset scoliosis (EOS). We examined a large cohort of patients with EOS to determine whether the law of diminishing returns applies to MCGRs. METHODS: A prospectively collected, multicenter registry was queried for patients with EOS treated with MCGRs. Patients with only spine-based implants and a minimum of 2 years of follow-up were included; patients with congenital scoliosis, single rods, <3 lengthenings, or >25% missing data were excluded. Patients were analyzed in 3 cohorts: primary MCGR (pMCGR) had first-time MCGR implants, secondary MCGR (sMCGR) were converted from an MCGR to a new MCGR, and conversion MCGR (cMCGR) were converted from a non-MCGR implant to MCGR. RESULTS: A total of 189 patients in the pMCGR group, 44 in the cMCGR group, and 41 in the sMCGR group were analyzed. From post-MCGR placement to the most recent follow-up or pre-definitive procedure, there were no differences in the changes in major Cobb angle, T1-S1 height, or T1-T12 height over time between the pMCGR and cMCGR groups. There was a decrease in length achieved at subsequent lengthenings in all cohorts (p < 0.01), and the sMCGR group had a significantly poorer ability to lengthen at each subsequent lengthening versus the pMCGR and cMCGR groups (p < 0.02). The 1-year survival rate was 90.5% for pMCGR, 84.1% for sMCGR, and 76.4% for cMCGR; 2-year survival was 61.5%, 54.4%, and 41.4%, respectively; and 3-year survival was 37.6%, 36.7%, and 26.9%, respectively. Excluding MCGRs still expanding, 27.6% of pMCGRs, 8.8% of sMCGRs, and 17.1% of cMCGRs reached the maximum excursion. Overall, 21.7% reached the maximum excursion. Within the pMCGR cohort, idiopathic and neuromuscular etiologies had a decline in lengthening achieved over time (p < 0.001), while syndromic EOS demonstrated a preserved ability to lengthen over time (p = 0.51). When the etiological groups were compared with each other, the neuromuscular group had the least ability to lengthen over time (p = 0.001 versus syndromic, p = 0.02 versus idiopathic). CONCLUSIONS: The MCGR experiences the law of diminishing returns in patients with EOS. We found that only 21.7% of rods expanded to within 80% of the maximum excursion. LEVEL OF EVIDENCE: Therapeutic Level III . See Instructions for Authors for a complete description of levels of evidence.

Construct Validity of Pediatric PROMIS Computerized Adaptive Testing Measures in Children With Adolescent Idiopathic Scoliosis.

BACKGROUND: The use of patient-reported outcome measures, especially Patient-Reported Outcomes Measurement Information System (PROMIS) measures, has increased in recent years. Given this growth, it is imperative to ensure that the measures being used are validated for the intended population(s)/disease(s). Our objective was to assess the construct validity of 8 PROMIS computer adaptive testing (CAT) measures among children with adolescent idiopathic scoliosis (AIS). METHODS: We prospectively enrolled 200 children (aged 10 to 17 y) with AIS, who completed 8 PROMIS CATs (Anxiety, Depressive Symptoms, Mobility, Pain Behavior, Pain Interference, Peer Relationships, Physical Activity, Physical Stress Experiences) and the Scoliosis Research Society-22r questionnaire (SRS-22r) electronically. Treatment categories were observation, bracing, indicated for surgery, or postoperative from posterior spinal fusion. Construct validity was evaluated using known group analysis and convergent and discriminant validity analyses. Analysis of variance was used to identify differences in PROMIS T -scores by treatment category (known groups). The Spearman rank correlation coefficient ( rs ) was calculated between corresponding PROMIS and SRS-22r domains (convergent) and between unrelated PROMIS domains (discriminant). Floor/ceiling effects were calculated. RESULTS: Among treatment categories, significant differences were found in PROMIS Mobility, Pain Behavior, Pain Interference, and Physical Stress Experiences and in all SRS-22r domains ( P <0.05) except Mental Health ( P =0.15). SRS-22r Pain was strongly correlated with PROMIS Pain Interference ( rs =-0.72) and Pain Behavior ( rs =-0.71) and moderately correlated with Physical Stress Experiences ( rs =-0.57). SRS-22r Mental Health was strongly correlated with PROMIS Depressive Symptoms ( rs =-0.72) and moderately correlated with Anxiety ( rs =-0.62). SRS-22r Function was moderately correlated with PROMIS Mobility ( rs =0.64) and weakly correlated with Physical Activity ( rs =0.34). SRS-22r Self-Image was weakly correlated with PROMIS Peer Relationships ( rs =0.33). All unrelated PROMIS CATs were weakly correlated (| rs |<0.40). PROMIS Anxiety, Mobility, Pain Behavior, and Pain Interference and SRS-22r Function, Pain, and Satisfaction displayed ceiling effects. CONCLUSIONS: Evidence supports the construct validity of 6 PROMIS CATs in evaluating AIS patients. Ceiling effects should be considered when using specific PROMIS CATs. LEVEL OF EVIDENCE: Level II, prognostic.

When Is an Isolated Olecranon Fracture Pathognomonic for Osteogenesis Imperfecta?

BACKGROUND: Isolated fractures of the olecranon process of the ulna in pediatric patients with open physes are classically considered pathognomonic for osteogenesis imperfecta (OI). The purpose of this study was to distinguish the clinical manifestations of isolated olecranon fractures in patients with and without OI to help practitioners assess when further evaluation for OI may be necessary. METHODS: All patients younger than 18 years old who were treated for an isolated olecranon fracture at a pediatric tertiary care center between 2009 and 2021 were identified. Patients without radiographs available for review, those with known skeletal dysplasia other than OI, and patients with multiple fractures (eg, polytraumas) or with concomitant dislocations were excluded. Of the 701 patients identified, 403 were included for analysis. Demographic variables, mechanism of injury, treatment type, and determination of OI diagnosis were collected. Patients with a previously confirmed diagnosis of OI or with genetic confirmation of OI following their fracture were designated as OI (+), and the remainder were designated OI (-). The Mann-Whitney U and χ2 tests were used to compare groups. RESULTS: Of the 403 patients, the median age was 7.8 years (interquartile range 5.2 to 12.5), and 270 (67%) were male. There were 14 confirmed cases of OI (3.5%). The OI (+) and OI (-) groups did not differ significantly by age or sex (P>0.05). OI (+) patients were more likely to sustain an injury from low-energy mechanisms (86% vs. 32%, P<0.001), sustain displaced fractures (86% vs. 21%, P<0.001) and undergo operative treatment (86% vs. 20%, P<0.001), and to report a history of previous fracture (79% vs. 16%, P<0.001) than OI (-) patients. 36% of OI (+) patients sustained a second olecranon fracture during the study period; there were no subsequent olecranon fractures in the OI (-) group. CONCLUSIONS: Isolated olecranon fractures may not be pathognomonic for OI. However, orthopaedists must be vigilant about the possibility of OI in patients who sustain displaced, isolated olecranon fractures under low-energy mechanisms with a history of previous fracture(s). LEVEL OF EVIDENCE: Level III.

Morphometric analysis of the proximal thoracic pedicles in Lenke II and IV adolescent idiopathic scoliosis: an evaluation of the feasibility for pedicle screw insertion.

PURPOSE: Pedicles on the concave side of the proximal thoracic (PT) curve in adolescent idiopathic scoliosis (AIS) patients with Lenke II and IV deformities tend to be narrow and dysplastic, making pedicle screw (PS) insertion challenging. The aim of this study was to evaluate the feasibility for PS placement in these patients using pedicle chord length, diameter, and channel morphology. METHODS: In this retrospective study, 56 consecutive AIS patients with Lenke II or IV curves who underwent instrumented posterior spinal fusion (PSF) were studied. The mean age at surgery was 14.8 years and the mean PT curve measured 45°. Two independent investigators evaluated all visible pedicles from T1 to T6 vertebral levels using axial images from intraoperative computed tomography-guided navigation recording the pedicle: (1) maximum transverse diameter 'd' at the isthmus, (2) maximum chord length 'l', and (3) qualitative assessment of the channel morphology (types A-D). RESULTS: Two hundred and sixty-eight concave and 264 convex pedicles were measured. The mean 'd' of the concave pedicles at T3 and T4 was < 3.0 mm, compared to > 5.0 mm for the convex counterparts (p < 0.001). Of all concave pedicle channels, 48% had morphology characteristics that were riskier for PS cannulation (type C or D) compared to 2% of all convex pedicle channels (type A or B) (p < 0.001). CONCLUSION: Almost half of all concave pedicles have morphologic characteristics that make them too small to accommodate a PS. Though PSs could be inserted using an in-out-in technique in these patients, alternative fixation anchors may improve strength and safety.

Characterizing Use of Growth-friendly Implants for Early-onset Scoliosis: A 10-Year Update.

BACKGROUND: Growth-friendly treatment of early-onset scoliosis (EOS) has changed with the development and evolution of multiple devices. This study was designed to characterize changes in the use of growth-friendly implants for EOS from 2007 to 2017. METHODS: We queried the Pediatric Spine Study Group database for patients who underwent index surgery with growth-friendly implants from July 2007 to June 2017. In 1298 patients, we assessed causes of EOS; preoperative curve magnitude; age at first surgery; patient sex; construct type; lengthening interval; incidence of "final" fusion for definitive treatment; and age at definitive treatment. α=0.05. RESULTS: From 2007 to 2017, the annual proportion of patients with idiopathic EOS increased from 12% to 33% (R=0.58, P=0.006). Neuromuscular EOS was the most common type at all time points (range, 33% to 44%). By year, mean preoperative curve magnitude ranged from 67 to 77 degrees, with no significant temporal changes. Mean (±SD) age at first surgery increased from 6.1±2.9 years in 2007 to 7.8±2.5 years in 2017 (R=0.78, P<0.001). As a proportion of new implants, magnetically controlled growing rods increased from <5% during the first 2 years to 83% in the last 2 years of the study. Vertically expandable prosthetic titanium ribs decreased from a peak of 48% to 6%; growth-guidance devices decreased from 10% to 3%. No change was seen in mean surgical lengthening intervals (range, 6 to 9 mo) for the 614 patients with recorded lengthenings. Final fusion was performed in 88% of patients who had undergone definitive treatment, occurring at a mean age of 13.4±2.4 years. CONCLUSIONS: From 2007 to 2017, neuromuscular EOS was the most common diagnosis for patients treated with growth-friendly implants. Patient age at first surgery and the use of magnetically controlled growing rods increased during this time. Preoperative curve magnitude, traditional growing rod lengthening intervals, and rates of final fusion did not change. LEVEL OF EVIDENCE: Level II.

Difficulties in Treating Postirradiation Kyphosis in Adults: A Series of Five Cases.

STUDY DESIGN: Clinical case series. OBJECTIVE: To assess objective outcomes of surgical correction of post-external beam radiation therapy (ERBT) kyphosis in a series of five adults. SUMMARY OF BACKGROUND DATA: EBRT is a well-established treatment for many cancers in children and adults. One complication associated with EBRT is postirradiation spine deformity. Scoliosis is the most common deformity, but kyphosis also occurs frequently. Differences in deformity patterns are likely related to the location and intensity of radiation. To our knowledge, no studies have addressed treatment of these deformities in adults, and the most recent case series (of children) was published in 2005. METHODS: We present a series of five adults who underwent surgery for postirradiation kyphosis, with a mean follow-up of 3.8 years (range, 2.5-6.2 years). RESULTS: Surgery improved the kyphotic deformity in all patients. Overall mean kyphotic deformity correction was 56° and was larger for cervical/cervicothoracic deformities (mean, 76°) than for lumbar deformities (mean, 42°) at midterm follow-up. Patients reported significant improvements in pain and self-image. Consistent with prior case series of children, we observed a high rate of complications (mean, 1.4 complications per patient) in adults. Three patients each underwent an unplanned surgical procedure because of a complication. CONCLUSION: The surgical treatment of postirradiation kyphotic spinal deformity is challenging, with common postoperative complications such as infection, instrumentation failure, and pseudarthrosis. However, with modern surgical techniques and spinal instrumentation, excellent deformity correction can be achieved and maintained. We recommend performing a two-stage procedure for cervicothoracic deformity, with anterior release followed by posterior fusion and instrumentation. In thoracolumbar deformities, correction can be achieved through single-stage posterior fusion. Rigid spinopelvic fixation with sacral-alar-iliac screws and second-stage anterior lumbar interbody fusion at L5-S1 is recommended to reduce nonunion risk. Cement augmentation of proximal and distal anchors can help prevent junctional failure. LEVEL OF EVIDENCE: Level IV.

The Military Extremity Trauma Amputation/Limb Salvage (METALS) Study: Outcomes of Amputation Compared with Limb Salvage Following Major Upper-Extremity Trauma.

BACKGROUND: Severe upper-extremity injuries account for almost one-half of all extremity trauma in recent conflicts in the Global War on Terror. Few long-term outcomes studies address severe combat-related upper-extremity injuries. This study's objective was to describe long-term functional outcomes of amputation compared with those of limb salvage in Global War on Terror veterans who sustained severe upper-extremity injuries. Limb salvage was hypothesized to result in better arm and hand function scores, overall functional status, and quality of life, with similar pain interference. METHODS: This retrospective cohort study utilized data from the Military Extremity Trauma Amputation/Limb Salvage (METALS) study for a subset of 155 individuals who sustained major upper-extremity injuries treated with amputation or limb salvage. Participants were interviewed by telephone 40 months after injury, assessing social support, personal habits, and patient-reported outcome instruments for function, activity, depression, pain, and posttraumatic stress. Outcomes were evaluated for participants with severe upper-extremity injuries and were compared with participants with concomitant severe, lower-extremity injury. The analysis of outcomes comparing limb salvage with amputation was restricted to the 137 participants with a unilateral upper-extremity injury because of the small number of patients with bilateral upper-extremity injuries (n = 18). RESULTS: Overall, participants with upper-extremity injuries reported moderate to high levels of physical and psychosocial disability. Short Musculoskeletal Function Assessment (SMFA) scores were high across domains; 19.4% screened positive for posttraumatic stress disorder (PTSD), and 12.3% were positive for depression. Nonetheless, 63.6% of participants were working, were on active duty, or were attending school, and 38.7% of participants were involved in vigorous recreational activities. No significant differences in outcomes were observed between patients who underwent limb salvage and those who underwent amputation. CONCLUSIONS: Severe, combat-related upper-extremity injuries result in diminished self-reported function and psychosocial health. Our results suggest that long-term outcomes are equivalent for those treated with amputation or limb salvage. Addressing or preventing PTSD, depression, chronic pain, and associated health habits may result in less disability burden in this population. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Pediatric Gartland Type-IV Supracondylar Humeral Fractures Have Substantial Overlap with Flexion-Type Fractures.

BACKGROUND: Knowledge is limited about the diagnosis and treatment of modified Gartland type-IV supracondylar humeral fractures. We determined the prevalence of type-IV fractures, identified preoperative characteristics associated with these injuries, and assessed operative treatment characteristics. METHODS: We retrospectively identified patients <16 years of age who underwent operative treatment of a supracondylar humeral fracture at 2 centers between 2008 and 2016. We compared patient, injury, and treatment characteristics between type-IV and type-III fracture groups (1:4, cases:controls). Preoperative radiographs were assessed by 4 pediatric orthopaedists blinded to fracture type. The odds of a fracture being type IV were assessed using univariate logistic regression for individual radiographic parameters. Significance was set at alpha = 0.05. RESULTS: Type-IV fractures accounted for 39 (1.3%) of the supracondylar humeral fractures treated operatively during the study period. A type-IV fracture was associated with the following radiographic parameters: flexion angulation (odds ratio [OR] = 17; 95% confidence interval [CI] = 4.9 to 59), valgus angulation (OR = 5.6; 95% CI = 1.6 to 20), and lateral translation (OR = 4.1; 95% CI = 1.6 to 11) of the distal fragment; osseous apposition between the proximal and distal fragments (OR = 4.0; 95% CI = 1.8 to 9.0); and propagation of the fracture line toward the diaphysis of the proximal segment (OR = 9.2; 95% CI = 1.6 to 53). We found no significant differences in patient or injury characteristics between the groups. Compared with type-III fractures, type-IV fractures were treated more frequently with open reduction and percutaneous pinning (13% compared with 3.8%; p = 0.04) and were associated with longer mean operative time (82 ± 42 compared with 63 ± 28 minutes; p = 0.001). CONCLUSIONS: We identified 5 preoperative radiographic parameters associated with greater odds of a supracondylar humeral fracture being type IV rather than type III. No patient or injury characteristic differed significantly between the groups. Substantial overlap likely exists between type-IV and flexion-type fractures. Type-IV fractures were associated with longer operative time and were treated with open reduction more frequently than were type-III fractures. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

"As Black as Ink": A Case of Alkaptonuria-Associated Myelopathy and a Review of the Literature.

STUDY DESIGN: Case report and literature review. OBJECTIVE: To characterize the rare presentation of myelopathy occurring secondary to alkaptonuria and to evaluate the available evidence regarding its treatment. SUMMARY OF BACKGROUND DATA: Alkaptonuria is an autosomal recessive genetic condition with an estimated incidence of 1 in 250,000 to 1 in 1,000,000 people. Mutation of the enzyme homogentisate 1,2-dioxygenase leads to the production of high levels of homogentisic acid, with subsequent deposition in ligaments, cartilage, and menisci. Involvement of the spine is termed "ochronotic spondyloarthropathy," of which myelopathy is an uncommon presentation. METHODS: We present the case of a 57-year-old man with alkaptonuria-associated myelopathy, who underwent surgical decompression. Ten additional cases were identified in the literature by a systematic search of PubMed and Google Scholar. RESULTS: In a patient presenting with myelopathy, alkaptonuria may be suspected because of medical history, family history, symptoms (including darkened urine, pigmented ear cartilage, and sclera), or radiographic changes, such as multilevel disc collapse, progressive wafer-like disc calcification, extensive osteophyte formation, and spinal deformity. The diagnosis can be confirmed by urine homogentisic acid testing. Of the 11 patients presented here or identified in the literature, 2 were treated nonoperatively, 8 were treated with decompressive spinal surgery, and treatment of the myelopathy was not discussed for 1 patient. In all cases in which outcomes were reported, substantial improvement in the patient's condition was seen. CONCLUSION: Alkaptonuria is a rare cause of myelopathy, but one that clinicians should understand. Although no disease-modifying treatment currently exists for alkaptonuria, the use of symptomatic treatments and, particularly, surgical decompression is recommended to address myelopathy if it develops. LEVEL OF EVIDENCE: 4.

Maxillary Reconstruction Using a Gullwing Fibula Osteofascial Flap and Flexor Hallucis Longus Muscle.

The appropriate reconstruction of an infrastructure maxillectomy defect requires vascularized bone for maxillary arch restoration, soft tissue bulk for filling the residual defect extending up to the orbital floor, and a thin tissue layer for resurfacing the palate and adjacent cheek mucosa. Although several free tissue flaps have been previously described as reconstructive options, each possesses limitations. We describe the fibula osteofascial flap with flexor hallucis longus muscle, no skin paddle, and a "gullwing" fascial component, as an ideal reconstructive option for these specific maxillary defects. It satisfies the necessary requirements of bone, restoration of intraoral surfaces, as well as additional soft tissue volume to provide the optimal aesthetic and functional result. It also has the added benefit of minimizing morbidity to, and improving aesthetics of, the donor site. This is demonstrated through a case presentation and review of the existing literature.

Miniature Negative Pressure Dressings on Forearm Donor Sites after Radial Forearm Flap Harvest.

Management of radial forearm donor sites following free flap reconstruction of head and neck tumor defects typically requires split-thickness skin grafting. Tendon exposure and delayed healing are occasional problems associated with skin grafting over the distal forearm musculature. Others have reported the use of negative pressure wound therapy (NPWT) devices to bolster split-thickness grafts and improve graft take. Although this approach works well, these devices are not always approved by third-party payers for outpatient use, requiring patients to remain in the hospital or have these devices removed before discharge. The authors report outcomes using a miniaturized NPWT device to bolster the skin graft on radial forearm free flap donor sites in 10 consecutive patients compared with 10 consecutive control patients managed with traditional bolster dressings. The 2 groups of patients were similar in terms of demographics, indication for reconstruction, and size of donor site. There was less skin graft loss and a lower rate of tendon exposure and infection in the miniaturized NPWT device group, though these results did not reach statistical significance. Recently developed miniaturized, single-use NPWT devices can be reliably used as bolsters for skin grafts with some notable advantages over reusable NPWT devices.