Charles H. Crawford

Temporal progression of angiogenesis and basal lamina deposition after contusive spinal cord injury in the adult rat

After spinal cord injury (SCI), the absence of an adequate blood supply to injured tissues has been hypothesized to contribute to the lack of regeneration. In this study, blood vessel changes were examined in 28 adult female Fischer 344 rats at 1, 3, 7, 14, 28, and 60 days after a 12.5 g · cm NYU impactor injury at the T9 vertebral level. Laminin, collagen IV, endothelial barrier antigen (SMI71), and rat endothelial cell antigen (RECA‐1) immunoreactivities were used to quantify blood vessel per area densities and diameters in ventral gray matter (VGM), ventral white matter (VWM), and dorsal columns (DC) at levels ranging 15 mm rostral and caudal to the epicenter. This study demonstrates an angiogenic response, defined as SMI71/RECA‐1–immunopositive endothelial cells that colocalize with a robust deposition of basal lamina and basal lamina streamers, 7 days after injury within epicenter VGM. This angiogenesis diminishes concurrent with cystic cavity formation. GAP43‐ and neurofilament‐ (68 kDa and 210 kDa) immunopositive fiber outgrowth was associated with these new blood vessels by day 14. Between 28 and 60 days after injury, increases in SMI71‐immunopositive blood vessel densities were observed in the remaining VWM and DC with a corresponding increase in vessel diameters up to 15 mm rostral and caudal to the epicenter. This second angiogenesis within VWM and DC, unlike the acute response observed in VGM, did not correspond to any previously described changes in locomotor behaviors in this model. We propose that therapies targeting angiogenic processes be directed at the interval between 3 and 7 days after SCI. J. Comp. Neurol. 445:308–324, 2002.

Major Complications and Comparison Between 3-column Osteotomy Techniques in 105 Consecutive Spinal Deformity Procedures

Study Design. A retrospective review. Objective. To characterize the risk factors for the development of major complications in 3-column osteotomies and determine whether the presence of a major complication affects ultimate clinical outcomes. Summary of Background Data. Three-column spinal osteotomies, including pedicle subtraction osteotomy (PSO) and vertebral column resection (VCR), are common techniques to correct severe and/or rigid spinal deformities. Methods. Two hundred forty consecutive PSO (n = 156) and VCR (n = 84) procedures in 237 patients were performed at a single institution between 1995 and 2008. Of these, 105 patients (87 PSOs, 18 VCRs) had complete preoperative and minimum 2-year postoperative clinical outcomes data available for analysis. Using established criteria, we reported complications as major or minor and further stratified complications as surgical versus medical and permanent versus transient. Risk factors for complications and their effect on Scoliosis Research Society (SRS) clinical outcomes at baseline and at 2 years or more were assessed. Results. Major medical and surgical complications occurred at similar rates in both PSOs and VCRs (38%, 33 of 87 vs. 22%, 4 of 18; P = 0.28). Overall, 24.8% (26 of 105) experienced major surgical complications (3 permanent) and 15.2% (16 of 105) experienced major medical complications (4 permanent). Patients with PSO were older (53 vs. 29 yr; P < 0.001), had greater estimated blood loss (1867 vs. 1278 mL; P = 0.02), and showed a trend toward fewer fused levels (10.1 vs. 12.2; P = 0.06). Risk factors for major complications included preoperative sagittal imbalance of 40 mm or more (P = 0.01), age 60 years and older (P = 0.01), and the presence of 3 or more medical comorbidities (P = 0.04). Both groups improved significantly from baseline in SRS subscores; however, patients with PSO started off worse but improved more than VCRs in both the pain (+1.0 vs. +0.1; P < 0.001) and function (+0.6 vs. +0.2; P = 0.01) domains, with no differences in final satisfaction (4.1 vs. 4.3; P = 0.54). PSO and VCR patients with no complications had slightly higher satisfaction scores than patients with minor-only complications, major transient complications, and major permanent complications. There were no significant differences among the groups with respect to change in SRS subscores from baseline, and all complication groups improved significantly from baseline (P = 0.04). Conclusion. Major complications occurred in 35% of 3-column osteotomies and at similar rates for both PSO (38%) and VCR (22%) procedures. The presence of a major complication did not affect the ultimate clinical outcomes at 2 years or more.

Anatomic double bundle ACL reconstruction: a literature review

With the abundance of anatomic double bundle ACL reconstruction techniques that currently exist and limited patient outcome data, one has to ask whether or not they should be used and if so, which one, and what is the learning curve for the average knee surgeon to become competent with the technique that they select? The purpose of this literature review is to summarize existing anatomic double bundle ACL reconstruction surgical and rehabilitation techniques and the clinical and biomechanical study evidence that currently exists. In choosing to perform anatomic double bundle ACL reconstruction we suggest that the knee surgeon should look for evidence of: (1) control of the pivot shift phenomenon, (2) improved transverse plane rotatory knee control during the performance of sports type movements, (3) a decreased likelihood of revision procedures either for ACL reconstruction or for treatment of associated primary or recurrent meniscal injuries, (4) improved patient self-reports of perceived function, satisfaction, and quality of life, and (5) radiographic evidence of a lower incidence and/or magnitude of osteoarthritic changes compared to conventional single bundle ACL reconstruction.

Growth modulation by means of anterior tethering resulting in progressive correction of juvenile idiopathic scoliosis: A case report

The treatment of juvenile idiopathic scoliosis continues to evolve with the search for ways to positively affect the natural history of deformity progression and disability while minimizing treatment morbidity1. Traction, bracing, and casting are often the first treatment attempts to control the deformity, although many deformities will progress to surgical intervention1,2. The goals of surgical treatment include correcting the deformity, or preventing progression of the deformity, while minimizing morbidity1. Currently, deformity correction with instrumentation and fusion is the most commonly recommended and performed surgical intervention1. Specific concerns associated with fusion include the cessation of spinal growth over the fused segments3 (which may negatively affect pulmonary function4,5) and the potential for disc degeneration of segments adjacent to a long fusion. Because nonoperative treatment does not control progression in all cases1,2, the search for alternative treatment of juvenile idiopathic scoliosis is warranted1,6-12. Growth-modulating surgical treatments of scoliosis have interested surgeons for nearly a half century, although initial attempts at growth modulation were abandoned because of disappointing results13,14. Advances in surgical techniques and implant technology have renewed interest in fusionless growth modulation for the treatment of scoliosis6-12. Reported techniques for human use include posterior growing rods7 and anterior vertebral body stapling6,8. Animal studies and computer simulation models have confirmed that mechanical tethering of the spine can induce and correct scoliotic deformities15-19. In the present report, we describe the case of a young boy with juvenile scoliosis in whom anterior tethering resulted in gradual correction over four years. We are not aware of any previous such report in the literature. The patient and …

Perioperative complications of recombinant human bone morphogenetic protein-2 on an absorbable collagen sponge versus iliac crest bone graft for posterior cervical arthrodesis.

Study Design. Retrospective evaluation of perioperative complications with recombinant human bone morphogenetic protein-2 on an absorbable collagen sponge (rhBMP-2/ACS) versus iliac crest bone graft (ICBG) for instrumented posterior cervical fusion. Objective. To determine the risk of perioperative complications using rhBMP-2/ACS for posterior cervical fusion compared with ICBG. Summary of Background Data. There is substantial use of rhBMP-2/ACS as a bone graft substitute for spine fusions outside the Food and Drug Administration-approved indication of anterior lumbar interbody fusion. Efficacy for inducing fusion and avoidance of iliac crest donor-site complications are frequent reasons cited for its use. Previous studies have reported use in the anterior lumbar spine, the posterior lumbar spine, and in the anterior cervical spine. Site-specific perioperative complications that have been reported, especially with use in the anterior cervical spine, confirm that safety and efficacy should be established for specific anatomic sites and clinical indications. Methods. From July 2002 to February 2005, a consecutive series of patients who underwent instrumented posterior cervical fusion were identified. Patients received either rhBMP-2/ACS or ICBG based on the discretion of the surgeon. Patients were excluded if they had a preoperative diagnosis of trauma, tumor, or infection, or if they underwent a concomitant anterior procedure. Seventy-seven patients met the inclusion criteria. Forty-one of these patients received rhBMP-2/ACS and 36 received ICBG. Standard demographic, surgical, and perioperative complication data were collected from the medical records. Results. There were no significant differences in age, gender distribution, smoking status, number of surgical levels, blood loss, operative time, or length of stay between the 2 groups. There were more posterior cervical wound complications requiring treatment in the rhBMP- 2/ACS group (6, 14.6%) versus the ICBG group (1, 2.8%), although this was not statistically significant (P = 0.113). One patient (2.8%) in the ICBG group had a wound complication at the iliac crest donor site. Additional perioperative complications were noted in 3 patients (7.3%) in the ICBG group and none in the rhBMP-2/ACS group. Conclusion. The higher incidence of posterior cervical wound complications in the rhBMP-2/ACS group, although not statistically significant, may be related to an inflammatory response to rhBMP-2. This potential risk must be weighed against the elimination of donor-site complications associated with ICBG harvesting, and considered in light of ultimate clinical outcome. Additional studies are needed to clarify this issue, as well as to determine optimal dosing and carrier for usage in the posterior cervical spine.

Does a long-fusion "t3-Sacrum" portend a worse outcome than a short-fusion "t10-Sacrum" in primary surgery for adult scoliosis?

Study Design. Retrospective clinicoradiographic analysis. Objective. To compare the upper thoracic (UT) and lower thoracic (LT) spines as the upper instrumented vertebra in primary fusions to the sacrum for adult scoliosis. Summary of Background Data. The optimal level at which a fusion to the sacrum is terminated proximally for adult scoliosis remains controversial. We hypothesized that (1) UT spine would have an increased pseudarthrosis, more perioperative complications, and worse outcomes and (2) LT spine would have more proximal junctional kyphosis. Methods. Patients who underwent primary surgery for adult scoliosis between 2002 and 2006 were studied. UT and LT groups were matched cohorts. Minimum follow-up for all patients was 2 years. Scoliosis Research Society scores and Oswestry Disability Index were the clinical outcome measures. Results. Fifty-eight patients (UT = 20, LT = 38) with a mean age of 55.7 years were followed for an average of 3.0 ± 1.1 years. The UT group had greater preoperative thoracic kyphosis and coronal Cobb values (P < 0.05). Diagnoses were idiopathic scoliosis (75.9%) and degenerative scoliosis (24.1%). The UT cohort had a greater number of levels fused (15.8 vs. 8.6) and higher blood loss (1350 mL vs. 811 mL). Operative time, recombinant human bone morphogenetic protein-2 per level, and caudal interbody grafting (80.0% UT vs. 89.5% LT) were similar. The UT group experienced an increased number of perioperative complications (30.0% vs. 15.8%), more pseudarthrosis (20.0% vs. 5.3%), and a higher prevalence of revision surgery (20.0% vs. 10.5%). The LT group had more proximal junctional kyphosis (18.4% vs. 10.0%). Scoliosis Research Society scores and Oswestry Disability Index were improved in both cohorts in all domains (P < 0.001), except function (P = 0.07) and mental health (P = 0.27), which were not significantly improved in the UT group. Conclusion. With long fusions to the sacrum, one should anticipate more perioperative complications, a higher pseudarthrosis rate, and perhaps more revision surgery than short fusions. Short fusions may result in a more proximal junctional kyphosis, only rarely requiring revision surgery.

Femoral component revision using an extensively hydroxyapatite-coated stem☆

Femoral component revisions with extensively coated stems have shown promising clinical results, although concerns over stress shielding still exist. We retrospectively reviewed 59 patients undergoing femoral component revision with an extensively hydroxyapatite (HA)-coated stem. The average length of follow-up was 3.3 years (range, 2-5 years). The average preoperative Harris Hip Score was 43 points, which improved to 86 points at the latest follow-up (P < .01). The overall mechanical failure rate was 2%. No evidence of stress shielding was seen in 78% of patients. The clinical results of this series using an extensively HA-coated stem are similar to those using an extensively porous-coated stem. Long-term follow-up is required to determine if an extensively HA-coated implant will be superior to an extensively porous-coated implant with regard to stress shielding.

Treatment of bicondylar tibia plateau fractures using locked plating versus external fixation.

Bicondylar tibial plateau fractures can be difficult to treat due to the extent of articular cartilage, metaphyseal bone, and soft tissue injury. The purpose of this study was to compare the outcomes of open reduction and locked plating vs fine-wire external fixation of 58 consecutive bicondylar tibial plateau fractures at a level I trauma center. All bicondylar tibial plateau fractures were classified as Schatzker V/VI or AO/OTA type 41C. Twenty-eight patients in one group were treated using a locked plating system, and 30 patients in another group were treated with a hybrid or circular external fixation frame. The 2 groups were similar demographically. When compared with external fixation, locked plating was associated with a decreased time to union (5.9 vs 7.4 months), decreased incidence of articular malunion (7% vs 40%; P=.003), decreased knee stiffness (4% vs 13%), and decreased overall complications (27% vs 48%). The Schatzker VI subgroup accounted for 25 of the 27 complications (93%) in the locked plating group and 40 of the 48 complications (83%) in the external fixation group. We reserve the use of external fixation devices in the treatment of tibial plateau fractures to span the fracture site until the patient is amenable to definitive fixation with locked plating.

Acetabular Component Revision Using a Porous Tantalum Biomaterial: A Case Series

Biologic ingrowth can be difficult to achieve in acetabular component revision, especially in cases with significant bone loss. The purpose of this study was to review our clinical results of acetabular component revisions in patients with significant bone loss using a porous tantalum biomaterial. This is a retrospective review of 25 patients. There were 16 females and 9 males with a mean age of 71.7 +/- 10.54 years. The mean follow up was 39 +/- 11.09 months (range, 28-55 months). All patients in this series had combined segmental and cavitary bone loss, Paprosky type 2 or type 3. Of 22 patients in this series, 21 had a well-fixed and functioning implant at latest follow up. All 21 patients developed ingrowth along the tantalum surface despite compromised host bone. There were no cases of dislocation or aseptic loosening. Porous tantalum appears to be a promising material for use in revision hip arthroplasty to facilitate biologic ingrowth in patients with acetabular bone loss.

Relationship Among United States Medical Licensing Step I, Orthopedic In-Training, Subjective Clinical Performance Evaluations, and American Board of Orthopedic Surgery Examination Scores: A 12-Year Review of an Orthopedic Surgery Residency Program

OBJECTIVE To improve the understanding of relationships among United States Medical Licensing Examination (USMLE Step I), Orthopedic In-Training Examination (OITE), Subjective Clinical Performance Evaluations, and American Board of Orthopedic Surgery Examination Part I (Abos-I) and Part II (Abos-II), which would help residency programs better achieve their educational mission. DESIGN A 12-year descriptive study of retrospectively collected data. SETTING One residency program with 47 resident participants. RESULTS Residents that failed Abos-I and Abos-II had lower program mean OITE year-in-training (YIT) percentile rank scores. The program mean OITE YIT percentile rank score had a moderate relationship with Abos-I (% correct) score (r = 0.68, p < 0.0001) and an insignificant relationship with USMLE Step I (3-digit) score (r = 0.22, p = 0.13). Residents with upper quartile (>or=220) USMLE Step I (3-digit) scores for our program had higher program mean OITE YIT percentile rank scores and Abos-I (% correct) scores than residents with lower quartile scores (<or=202). Residents who scored in the upper quartile (>or=55) for the program mean OITE YIT percentile rank score had higher Abos-I (% correct) scores than residents who did not. Residents who scored in the lower quartile for the third postgraduate year (PGY-3) program OITE YIT percentile rank score or for the program mean OITE YIT percentile rank score had a 5.2 and 5.8 time greater Abos-I failure risk, respectively. The program PGY-3 OITE YIT percentile rank score was the strongest Abos-I (% correct) score discriminator. Resident Abos-I (% correct), program mean OITE YIT, and program PGY-3 OITE YIT percentile rank scores were the strongest discriminators for Abos-II passage. Residents with a program mean OITE YIT percentile rank score >or=28, program PGY-3 OITE YIT percentile rank score >or=39, and USMLE Step I (3-digit) score >or=207 were more likely to pass Abos-I and II. Residents that had lower quartile USMLE Step I (3-digit) scores for our program had a 2.3 time greater Abos-I failure risk. Program residents with >or=2 below-average subjective clinical performance evaluations had lower Abos-I (% correct) scores but had similar Abos-I and II pass rates. CONCLUSION Our program uses the USMLE Step I (3-digit) score as a preacceptance estimate of likely supplemental guided mentoring needs. Program mean OITE YIT percentile rank and PGY-3 OITE YIT percentile rank scores help identify educational deficiencies and predict eventual Abos-I and II passage. Subjective clinical performance evaluations provide important supplemental information regarding professionalism, communication, and patient care skills.