Impact of surgical risk factors for non-union on lumbar spinal fusion outcomes using cellular bone allograft at 24-months follow-up.

BACKGROUND: The current report investigates fusion rates and patient-reported outcomes following lumbar spinal surgery using cellular bone allograft (CBA) in patients with risk factors for non-union. METHODS: A prospective, open label study was conducted in subjects undergoing lumbar spinal fusion with CBA (NCT02969616) to assess fusion success rates and patient-reported outcomes in subjects with risk factors for non-union. Subjects were categorized into low-risk (≤ 1 risk factors) and high-risk (> 1 risk factors) groups. Radiographic fusion status was evaluated by an independent review of dynamic radiographs and CT scans. Patient-reported outcome measures included quality of life (EQ-5D), Oswestry Disability Index (ODI) and Visual Analog Scales (VAS) for back and leg pain. Adverse event reporting was conducted throughout 24-months of follow-up. RESULTS: A total of 274 subjects were enrolled: 140 subjects (51.1%) were categorized into the high-risk group (> 1 risk factor) and 134 subjects (48.9%) into the low-risk group (≤ 1 risk factors). The overall mean age at screening was 58.8 years (SD 12.5) with a higher distribution of females (63.1%) than males (36.9%). No statistical difference in fusion rates were observed between the low-risk (90.0%) and high-risk (93.9%) groups (p > 0.05). A statistically significant improvement in patient-reported outcomes (EQ-5D, ODI and VAS) was observed at all time points (p < 0.05) in both low and high-risk groups. The low-risk group showed enhanced improvement at multiple timepoints in EQ-5D, ODI, VAS-Back pain and VAS-Leg pain scores compared to the high-risk group (p < 0.05). The number of AEs were similar among risk groups. CONCLUSIONS: This study demonstrates high fusion rates following lumbar spinal surgery using CBA, regardless of associated risk factors. Patient reported outcomes and fusion rates were not adversely affected by risk factor profiles. TRIAL REGISTRATION: NCT02969616 (21/11/2016).

Adjunctive Use of Bone Growth Stimulation Increases Cervical Spine Fusion Rates in Patients at Risk for Pseudarthrosis.

STUDY DESIGN: A prospective multicenter clinical trial (NCT03177473) was conducted with a retrospective cohort used as a control arm. OBJECTIVE: The purpose of this study was to evaluate cervical spine fusion rates in subjects with risk factors for pseudarthrosis who received pulsed electromagnetic field (PEMF) treatment. SUMMARY OF BACKGROUND DATA: Certain risk factors predispose patients to pseudarthrosis, which is associated with prolonged pain, reduced function, and decreased quality of life. METHODS: Subjects in the PEMF group were treated with PEMF for 6 months postoperatively. The primary outcome measure was fusion status at the 12-month follow-up period. Fusion status was determined using anterior/posterior, lateral, and flexion/extension radiographs and computed tomography (without contrast). RESULTS: A total of 213 patients were evaluated (PEMF, n=160; Control, n=53). At baseline, the PEMF group had a higher percentage of subjects who used nicotine ( P =0.01), had osteoporosis ( P <0.05), multi-level disease ( P <0.0001), and were >65 years of age ( P =0.01). The PEMF group showed over two-fold higher percentage of subjects that had ≥3 risk factors (n=92/160, 57.5%) compared with the control group (n=14/53, 26.4%). At the 12-month follow-up, the PEMF group demonstrated significantly higher fusion rates compared with the control (90.0% vs. 60.4%, P <0.05). A statistically significant improvement in fusion rate was observed in PEMF subjects with multi-level surgery ( P <0.0001) and high BMI (>30 kg/m 2 ; P =0.0021) when compared with the control group. No significant safety concerns were observed. CONCLUSIONS: Adjunctive use of PEMF stimulation provides significant improvements in cervical spine fusion rates in subjects having risk factors for pseudarthrosis. When compared with control subjects that did not use PEMF stimulation, treated subjects showed improved fusion outcomes despite being older, having more risk factors for pseudarthrosis, and undergoing more complex surgeries.

Twenty-four-month interim results from a prospective, single-arm clinical trial evaluating the performance and safety of cellular bone allograft in patients undergoing lumbar spinal fusion.

BACKGROUND: Autologous bone grafts are the gold standard for spinal fusion; however, harvesting autologous bone can result in donor site infection, hematomas, increased operative time, and prolonged pain. Cellular bone allografts (CBAs) are a viable alternative that avoids the need for bone harvesting and may increase fusion success alone or when used as an adjunct material. The present study examined the efficacy and safety of CBA when used as an adjunct graft material to lumbar arthrodesis. METHODS: A prospective, single-arm, multicenter clinical trial (NCT02969616) was conducted in adult subjects (> 18 years of age) undergoing lumbar spinal fusion with CBA graft (CBA used as primary (≥ 50% by volume), with augmentation up to 50%). Radiographic fusion status was assessed by an independent review of dynamic radiographs and CT scans. Clinical outcomes were assessed with the Oswestry Disability Index (ODI), and Visual Analog Scales (VAS) score for back and leg pain. Adverse events were assessed through the 24-month follow-up period. The presented data represents an analysis of available subjects (n = 86) who completed 24 months of postoperative follow-up at the time the data was locked for analysis. RESULTS: Postoperative 24-month fusion success was achieved in 95.3% of subjects (n = 82/86) undergoing lumbar spinal surgery. Clinical outcomes showed statistically significant improvements in ODI (46.3% improvement), VAS-Back pain (75.5% improvement), and VAS-Leg pain (85.5% improvement) (p < 0.01) scores at Month 24. No subject characteristics or surgical factors were associated with pseudoarthrosis. A favorable safety profile with a limited number of adverse events was observed. CONCLUSIONS: The use of CBA as an adjunct graft material showed high rates of successful lumbar arthrodesis and significant improvements in pain and disability scores. CBA provides an alternative to autograft with comparable fusion success rates and clinical benefits. TRIAL REGISTRATION: NCT02969616.

Twelve-Month Results from a Prospective Clinical Study Evaluating the Efficacy and Safety of Cellular Bone Allograft in Subjects Undergoing Lumbar Spinal Fusion.

BACKGROUND: While autologous bone grafts remain the gold standard for spinal fusion procedures, harvesting autologous bone is associated with significant complications, including donor site infection, hematomas, increased operative time, and prolonged pain. Cellular bone allograft (CBA) presents an alternative to autologous bone harvesting, with a favorable efficacy and safety profile. The current study further investigates CBA as an adjunct to lumbar spinal fusion procedures. METHODS: A prospective, multicenter, open-label clinical study was conducted in subjects undergoing lumbar spinal fusion with CBA (NCT02969616). Radiographic fusion status was assessed by an independent review of dynamic radiographs and CT scans. Clinical outcome measures included the Oswestry Disability Index (ODI) and visual analogue scale (VAS) for back and leg pain. Adverse-event reporting was conducted throughout 12 months of follow-up. Available subject data at 12 months were analyzed. RESULTS: A total of 274 subjects were enrolled into the study, with available data from 201 subjects (73.3%) who completed 12 months of postoperative radiographic and clinical evaluation at the time of analysis. Subjects had a mean age of 60.2 ± 11.5 years. A higher number of women (n = 124, 61.7%) than men (n = 77, 38.3%) were enrolled, with a collective mean BMI of 30.6 + 6.5 kg/m2 (range 18.0-51.4). At month 12, successful fusion was achieved in 90.5% of subjects. A significant (p < 0.001) improvement in ODI, VAS-back, and VAS-leg clinical outcomes was also observed compared to baseline scores. One adverse event related to CBA (postoperative radiculopathy) was reported, with surgical exploration demonstrating interbody extrusion of graft material. This subject reported successful fusion at month 12. CONCLUSIONS: CBA represents a viable substitute for harvesting of autograft alone with a high rate of successful fusion and significant improvements in subject-reported outcomes, such as pain and disability. Positive benefit was observed in subjects reporting single and multiple risk factors for pseudoarthrosis.

Biomechanical Analysis of Cement Augmentation Techniques on Pedicle Screw Fixation in Osteopenic Bone: A Cadaveric Study.

STUDY DESIGN: Three techniques for cement injection into osteopenic pedicles for screw augmentation were compared in a cadaver model. OBJECTIVES: To compare the safety and efficacy of 3 techniques for cement augmentation of pedicle screws in a cadaver model. BACKGROUND: Cement augmentation of pedicle screws improves fixation in osteopenic spines. Some investigators have used kyphoplasty osteo introducers to inject viscous cement into the pedicle. In addition, a novel fenestrated tapping system was studied that leaves a threaded cement tract for final pedicle screw insertion. METHODS: This 3-phase biomechanical study compared cement augmentation effects on the cephalocaudal toggle of pedicle screws within 34 fresh osteopenic human cadaveric vertebrae. Phase 1 compared injection through a fenestrated tap to a direct injection. Phase 2 evaluated the fenestrated tap versus injection of more viscous cement using a kyphoplasty osteo inducer. Phase 3 compared kyphoplasty and direct injection techniques. Each vertebral body was prepared with each of the 2 techniques. The pedicle screws were subjected to 10,000 cycles of cephalocaudal toggling, and total vertical displacement of each screw head was measured. RESULTS: In a combined analysis, overall displacement was 2.26 ± 0.57 mm for the direct injection, 2.88 ± 0.56 mm for the kyphoplasty technique, and 3.74 ± 0.59 mm for the fenestrated tap (p < .01). In Phase 1, extravasation of cement occurred in 5% of the fenestrated tap, 86% of the direct injection. Phase 2 results showed that extravasation occurred in 0% for the fenestrated tap group and 18% for the kyphoplasty group. In Phase 3, extravasation of cement was 54% of the direct injection, compared with 31% of the kyphoplasty group. CONCLUSIONS: The novel fenestrated tap system provided less resistance to toggle than either of the other 2 techniques but provided a lower incidence of cement extravasation. More viscous cement injected using kyphoplasty technique provides a combination of safety and efficacy.

Radiographic and patient-based outcome analysis of different bone-grafting techniques in the surgical treatment of idiopathic scoliosis with a minimum 4-year follow-up: allograft versus autograft/allograft combination.

BACKGROUND CONTEXT: Autograft and allograft have been equally successful in achieving arthrodesis, but whether there is any difference in their effect on patient outcome, especially early, has not been determined. PURPOSE: To determine if autograft in addition to allograft is associated with decreased healing period pain, increased early function, or both. STUDY DESIGN: This is a retrospective comparative case series. PATIENT SAMPLE: A sample of 47 patients, 20 years or younger with adolescent idiopathic scoliosis treated by the same surgeon at the same institution using third-generation segmental spinal instrumentation and arthrodesis. OUTCOME MEASURE: Function and pain were quantified at periodic intervals using the Scoliosis Research Society (SRS) health-related quality of life (HRQoL) questionnaire. Clinical and radiographic follow-ups were completed. METHODS: Freeze-dried corticocancellous allograft (AL) was used in 26 patients and allograft plus iliac crest autograft (AL-AU) in 21 patients. Radiographs and outcome measures, including SRS-24 or SRS-22 HRQoL questionnaires, were obtained preoperatively and at intervals with a 4-year follow-up available for 92% (25/26) of AL patients and 90% (19/21) of AL-AU patients. RESULTS: There were no differences between the AL and AL-AU groups' ages, curve patterns, and complications. Neither group had a major complication or pseudoarthrosis. There were no main curve size differences at any interval. Pain scores were similar at all intervals: AL/AL-AU preoperative, 4.1/4.0; early follow-up (<1 year), 3.7/4.1; midterm follow-up (1-2 years), 4.4/4.6; and late follow-up (>3 years), 4.1/4.0. Function scores were also similar at all intervals: AL/AL-AU preoperative, 4.7/4.6; early follow-up, 4.2/4.3; midterm follow-up, 4.9/4.9; and late follow-up, 4.5/4.4. CONCLUSIONS: The addition of autograft to allograft did not result in decreased pain or increased function at any time interval up to 4 years. We conclude that the addition of iliac crest autograft does not result in any advantage over freeze-dried allograft alone in the treatment of adolescent idiopathic scoliosis.

Arthroscopic treatment of Pipkin type I femoral head fractures: a report of 2 cases.

Pipkin type I fractures historically have required open treatment, with the potential-associated morbidity. Two cases of arthroscopic fracture fragment excision are described. These were completed using standard techniques and introducing the application of Steinman pins, through an accessory anterior portal, for capture of the fragment. Both the patients had satisfactory outcomes. We conclude that hip arthroscopy is a valuable option for the treatment of Pipkin I fractures.

Implementation and enforcement of ventilator-associated pneumonia prevention strategies in trauma patients.

BACKGROUND: We hypothesized that strict enforcement of ventilator-associated pneumonia (VAP) prevention (VAPP) strategies would decrease the incidence of VAP and improve patient outcomes. METHODS: This retrospective study examined 696 consecutive ventilated patients in a Level One trauma center. Three study groups were compared: Pre-VAPP, VAPP implementation, and VAPP enforcement. Ventilator days were compared with occurrences of VAP, defined by the U.S. Centers for Disease Control and Prevention National Nosocomial Infection Surveillance criteria. Patients with and without VAP were compared to evaluate the effect of VAP on patient outcome. Fisher exact, Kruskal-Wallis, and chi-square analyses were used, and p < 0.05 was considered significant. RESULTS: During the pre-VAPP protocol period, 5.2 cases of VAP occurred per 1,000 days of ventilator support. The number of cases of VAP decreased to 2.4/1,000 days (p = 0.172) and 1.2/1,000 days (p = 0.085) in the implementation and enforcement periods, respectively. However, when including all trauma patients, regardless of head Abbreviated Injury Score (AIS) score, the difference in the rate of VAP was statistically significant in the enforcement period, but not in the implementation period, compared with the pre-VAPP period (p = 0.014 and 0.062, respectively). A significant decrease was seen in the mortality rate (p = 0.024), total hospital days (p = 0.007), intensive care unit days (p = 0.002), ventilator days (p = 0.002), and hospital charges (p = 0.03) in patients without VAP compared with patients having VAP. CONCLUSIONS: There was a statistically significant decrease in the occurrence of VAP with strict enforcement of a VAPP protocol, regardless of head AIS score. Although the difference in patients with a head AIS score <3 was not statistically significant, it was clinically meaningful, decreasing the already-low rate of VAP by half. Strict enforcement of VAPP protocols may be cost efficient for hospitals and prevent decreased reimbursement under the Medicare pay-for-performance strategies.

Residual deformity after treatment of pediatric femur fractures with flexible titanium nails.

INTRODUCTION: Procurvatum or anterior bow deformity is a potential complication after treatment of femur fractures with flexible titanium nails (FTNs). This article reports on a clinical evaluation of angulation after treating pediatric femur fractures with FTNs. The article also reports on a complementary investigation of potential causes of these deformities using a biomechanical model. METHODS: All pediatric femoral shaft fractures treated with FTNs over a 4-year period were reviewed. Fracture location, pattern, angulation, and nail shoe tip orientation were recorded from postoperative radiographs. Malunion was defined as greater than 10 degrees of angulation on the AP radiograph or greater than 15 degrees on the lateral view. As an adjunct to the clinical study, a synthetic femur model was created using midtransverse fractures. These femurs were nailed using 2 FTNs inserted so as to create constructs having the following combinations of nail shoe tip orientation: both anterior (AA), both posterior (PP), both neutral (NN), or 1 anterior and 1 posterior(AP). The resulting angular deformities noticeable upon gross inspection were then measured. RESULTS: Of the 70 fractures reviewed, malunion occurred in 16 fractures, of which 11 had increased anterior bow. A majority of malunions was observed in older children with middle third of the femur fractures. They were significantly more prevalent in transverse fractures compared with all other fracture patterns. Clinically, increased anterior bowing did not occur if 1 of the nails was positioned to resist procurvatum, as seen in the lateral radiograph. Depending on nail tip orientation, the biomechanical femur fracture model showed significant differences in mean deformations after nail placement: AA had 12.6 degrees of posterior bow compared with 14.8, 3.7, and 0.3 degrees of anterior bow for PP, NN, and AP, respectively. CONCLUSION: Anterior bowing greater than 15 degrees is the most common malunion noted in this series of femur fractures that were nailed using FTN's. We conclude that final nail shoe tip orientation influences the likelihood of anterior bow deformity. The likelihood of large anterior bowing may be reduced if at least 1 of the nails is inserted with the tip pointing in an anterior direction. LEVEL OF EVIDENCE/CLINICAL RELEVANCE: Level III.

Efficacy of a pneumonia prevention protocol in the reduction of ventilator-associated pneumonia in trauma patients.

BACKGROUND: We hypothesized that implementing evidence-based ventilator-associated pneumonia (VAP) prevention (VAPP) strategies would decrease the incidence of VAP, and that VAP affects patient outcomes. METHODS: A prospective study was performed with 331 consecutive ventilated trauma patients in a level one university teaching hospital. The VAPP protocol was modified to include elevation of the head of the bed more than 30 degrees , twice-daily chlorhexidine oral cleansing, a once-daily respiratory therapy-driven weaning attempt, and conversion from a nasogastric to an orogastric tube whenever possible. Ventilator days were compared with occurrences of nosocomial pneumonia, as defined by the U.S. Centers for Disease Control National Nosocomial Infection Surveillance criteria. Patients with and without VAP were compared to discern the effect VAP has on outcome. RESULTS: In 2003, there were 1,600 days of ventilator support with 11 occurrences of VAP (6.9/1,000 ventilator days). In 2004, there were two occurrences of VAP in 703 days of ventilation (2.8/1,000 ventilator days). In the analysis of outcomes of the patients with and without VAP, there was a statistically significant difference in total hospital days (38.7 +/- 26.2 vs. 13.3 +/- 15.5), ICU days (27.8 +/- 12.6 vs. 7.5 +/- 9.7), ventilator days (21.1 +/- 9.8 vs. 6.0 +/- 10.3), Functional Independence Measures (7.25 +/- 2.3 vs. 10.8 +/- 1.8), and hospital charges ($371,416.70 +/- $227,774.31 vs. $138,317.39 +/- $208,346.64)(p < 0.05 for all). The mortality rate did not decrease significantly (20% vs. 7.5%; p = NS). The difference in the mean Injury Severity Score in the two groups was not significant (21.9 +/- 9.6 vs. 16.7 +/- 11.4 points) and thus could not account for the differences in outcomes. CONCLUSION: These data suggest that a VAPP protocol may reduce VAP in trauma patients. Ventilator-associated pneumonia may result in more hospital, ICU, and ventilator days and higher patient charges.

Nonoperative management of epidural hematomas and subdural hematomas: is it safe in lesions measuring one centimeter or less?

BACKGROUND: Management of a patient with a closed head injury is based on neurologic status and computerized tomography scan results. We hypothesized that those patients with an epidural hematoma (EDH) or subdural hematoma (SDH) <1 cm in thickness could safely be treated nonoperatively. METHODS: We retrospectively reviewed charts of 204 consecutive patients with either an EDH or SDH. RESULTS: There were 122 lesions < or =1 cm and 82 lesions >1 cm. In the first group, 115 were managed nonoperatively, with 111 good outcomes (minimal deficit with a Rancho Los Amigos score [RLAS] > or =3), two poor outcomes (severely disabled with RLAS <3), and two deaths. Twenty-eight patients with lesions greater than 1 cm had concomitant cerebral edema (CE) with an 89% mortality rate. The mortality rate in this group without CE was 20%, demonstrating the presence of CE in this group may have adversely affected the mortality rate, regardless of intervention. CONCLUSIONS: This data suggests that EDH or SDH <1 cm thick can be safely managed nonoperatively unless there is concomitant CE.