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Christopher M Bono

Publications and source records attributed to Christopher M Bono.

35 records · Page 2Linked to original sources

Union rates using autologous platelet concentrate alone and with bone graft in high-risk foot and ankle surgery patients.

Adjuvant use of autologous platelet concentrate (APC) to assist bone healing in foot and ankle surgery has not been reported. This study examined the clinical results and complications after the adjuvant use of APC in high-risk patients undergoing elective foot and ankle surgery. Patients at risk for bone-healing complications were prospectively enrolled over a 6-month period for the intraoperative application of APC. Patients were followed every 2 weeks for radiographic union and complications. Sixty-two high-risk patients were enrolled, totaling 123 procedures. Mean patient age was 51 years (range, 16-76), there were 36 females and 26 males, and 24 patients were smokers. Overall, a 94% union rate was achieved at a mean of 41 days. For APC alone, the mean time to union was 40 days; when APC was used with autograft, the mean time to union was 45 days (p = .173, two-tailed t test). These data suggest that adjuvant APC results in an acceptable time to union and may be a useful adjunct to promote osseous healing in high-risk patients undergoing elective foot and ankle surgery.

Adolescent↗

The thoracolumbar injury severity score: a proposed treatment algorithm.

OBJECTIVE: Significant controversy exists regarding the optimal management of thoracolumbar injuries. This is in part due to the lack of understanding of the natural history of various injury subtypes and the absence of a universally accepted classification scheme that facilitates communication among care providers and assists in directing treatment. The Spine Trauma Study Group has developed an injury severity score based on three major variables: the mechanism of injury determined by radiographic appearance, the integrity of the posterior ligamentous complex, and the neurologic status of the patient. By systematically assigning specific point values within each category based on the severity of injury, a final severity score may be generated that can be used to help direct treatment. The goal of this work is to present a proposal of a detailed treatment algorithm to assist in the nonoperative or operative management of thoracolumbar injuries. METHODS: A detailed review of the world's spinal literature was performed to ascertain predictors of instability following thoracolumbar trauma. With use of known biomechanical and clinical outcome measures, an arbitrary assignment of point values to various injury descriptors was performed. The assessment of the validity of the severity score was compared retrospectively with a variety of selected cases representing the typical injury patterns under the three major injury groups: compression, translational/rotational, and distraction injuries. CONCLUSIONS: The proposed treatment algorithm is an attempt to assist physicians using best-evidence medicine in managing thoracolumbar spinal injuries. The final point flow chart with graduated treatment recommendations is only preliminary and needs to be validated through prospective cohort analysis. In addition, the importance of the chosen variables determining spinal stability must also be verified.

Algorithms↗

Temperatures within the lumbar disc and endplates during intradiscal electrothermal therapy: formulation of a predictive temperature map in relation to distance from the catheter.

STUDY DESIGN: Temperatures were measured in human cadaveric lumbar discs during intradiscal electrothermal therapy. OBJECTIVES: To determine if sufficient temperatures for collagen denaturation and nociceptive ablation can be achieved at clinically significant distances from the intradiscal electrothermal therapy heating catheter. SUMMARY OF BACKGROUND DATA: Previous cadaveric studies have contested the ability of the intradiscal electrothermal therapy catheter to produce sufficient temperatures to denature collagen and cause neural ablation within the posterior anulus of the disc. However, these experiments used clinically unrepresentative device placements along the anterolateral anulus. METHODS: Intradiscal electrothermal therapy was performed in 14 human cadaveric discs. Devices were inserted using a standard posterolateral approach to orient the heating catheter along the posterior anulus. Temperature recordings were collected using multiple sensors placed along the posterior anulus, anterior anulus, and endplates. RESULTS: Temperatures greater than 60 C and 65 C were achieved in 14 and 5 specimens, respectively, at distances up to 2 mm from the catheter. Between 2 and 4 mm, more than 60 C was achieved in all specimens. More than 45 C was achieved in all specimens at distances of 9 to 14 mm from the device. CONCLUSIONS: Temperatures sufficient for collagen denaturation and nociceptive ablation were detected at distances greater than previously documented. These data suggest that intradiscal electrothermal therapy's proposed heat-dependent mechanisms of action are achievable in most discs. Among other factors, interspecimen variability of maximum temperatures may help explain the somewhat inconsistent clinical results following intradiscal electrothermal therapy.

Adult↗

Similarities and differences in the treatment of spine trauma between surgical specialties and location of practice.

STUDY DESIGN: Questionnaires administered to practicing orthopedic and neurosurgical spine surgeons from various regions of the United States and abroad. OBJECTIVES: To determine similarities and differences in the treatment of spinal trauma. SUMMARY OF BACKGROUND DATA: Spinal trauma is generally referred to subspecialists of orthopedic or neurosurgical training. Prior studies have suggested that there is significant variability in the management of such injuries. METHODS: Questionnaires based on eight clinical scenarios of commonly encountered cervical, thoracic, and lumbar injuries were administered to 35 experienced spinal surgeons. Surgeons completed profile information and answered approximately one dozen questions for each case. Data were analyzed with SPSS software to determine the levels of agreement and characteristics of respondents that might account for a lack of agreement on particular aspects of management. RESULTS: Of the 35 surgeons completing the questionnaire, 63% were orthopedists, 37% were neurosurgeons, and 80% had been in practice for more than 5 years. Considerable agreement was found in the majority of clinical decisions, including whether or not to operate and the timing of surgery. Of the differences noted, neurosurgeons were more likely to obtain a MRI, and orthopedists were more likely to use autograft as a sole graft material. Physicians from abroad were, in general, more likely to operate and to use an anterior approach during surgery than physicians from the northeastern United States. CONCLUSIONS: More commonalities were identified in the management of spinal trauma than previously reported. When found, variability in opinion was related to professional and regional differences.

Adult↗

Critical analysis of trends in fusion for degenerative disc disease over the past 20 years: influence of technique on fusion rate and clinical outcome.

STUDY DESIGN: Critical analysis of the results reported in published literature. OBJECTIVES: The purpose of this study was to evaluate whether various technical advancements have affected the outcome of lumbar spinal fusion for degenerative disease by critically analyzing the available literature from the past two decades. SUMMARY OF BACKGROUND DATA: To improve fusion rate and clinical outcome, various surgical options for lumbar spinal fusion for degenerative disc disorders have been introduced over the past 20 years. However, an important fundamental question still remains: What has been the impact of these new techniques and innovations on surgical results? METHODS: A comprehensive computer search of the English literature from 1979 to 2000 concerning lumbar/lumbosacral spinal fusion was performed using the keywords degenerative, lumbar, and fusion. RESULTS: Numerous deficiencies were noted in the reviewed literature. Nearly half of the studies failed to specify methodologic design, and documentation of brace use, graft source, fusion location, and fusion rate was missing in 38, 10, 2, and 4 of the 84 articles reviewed, respectively. From the data gathered, a noticeable trend toward the increasing use of internal fixation was noted, accounting for 23% of fusions in the 1980s versus 41% in the 1990s. Despite this trend, an improvement in overall fusion rate or clinical outcome could not be demonstrated. CONCLUSIONS: Numerous technologic advancements in lumbar spine fusion have been made over the past 20 years. Future advances in care are dependent on review of reported results. The numerous deficiencies detected in the analyzed literature herald the necessity for a uniform system of outcomes reporting containing a core of critical demographic, perioperative, and postsurgical information. Although a shift toward a greater use of technology was noted in the published literature, the clinical benefit of this trend remains unclear.

Diffusion of Innovation↗

Low-back pain in athletes.

While most occurrences of low-back pain in athletes are self-limited sprains or strains, persistent, chronic, or recurrent symptoms are frequently associated with degenerative lumbar disc disease or spondylolytic stress lesions. The prevalence of radiographic evidence of disc degeneration is higher in athletes than it is in nonathletes; however, it remains unclear whether this correlates with a higher rate of back pain. Although there is little peer-reviewed clinical information on the subject, it is possible that chronic pain from degenerative disc disease that is recalcitrant after intensive and continuous nonoperative care can be successfully treated with interbody fusion in selected athletes. In general, the prevalence of spondylolysis is not higher in athletes than it is in nonathletes, although participation in sports involving repetitive hyperextension maneuvers, such as gymnastics, wrestling, and diving, appears to be associated with disproportionately higher rates of spondylolysis. Nonoperative treatment of spondylolysis results in successful pain relief in approximately 80% of athletes, independent of radiographic evidence of defect healing. In recalcitrant cases, direct surgical repair of the pars interarticularis with internal fixation and bone-grafting can yield high rates of pain relief in competitive athletes and allow a high percentage to return to play. Sacral stress fractures occur almost exclusively in individuals participating in high-level running sports, such as track or marathon. Treatment includes a brief period of limited weight-bearing followed by progressive mobilization, physical therapy, and return to sports in one to two months, when the pain has resolved.

Athletic Injuries↗

Thoracic pedicle screws: postoperative computerized tomography scanning assessment.

OBJECT: The authors evaluated the accuracy of placement of thoracic pedicle screws by performing postoperative computerized tomography (CT) scanning. A grading system is presented by which screw placement is classified in relation to neurological, bone, and intrathoracic landmarks. METHODS: One hundred eighty-five thoracic pedicle screws were implanted in 27 patients with the assistance of computer image guidance or fluoroscopy. Postoperative CT scanning was conducted to determine a grade for each screw: Grade I, entirely contained within pedicle; Grade II, violates lateral pedicle but screw tip entirely contained within the vertebral body (VB); Grade III, tip penetrates anterior or lateral VB; Grade IV, breaches medial or inferior pedicle; and Grade V, violates pedicle or VB and endangers spinal cord, nerve root, or great vessels and requires immediate revision. Based on anatomical morphometry, the spine was subdivided into upper (T1-2), middle (T3-6), and lower (T7-12) regions. Statistical analyses were performed to compare regions. The mean follow-up period was 37.6 months. The following postoperative CT scanning-documented grades were determined: Grade I, 160 screws (86.5%); Grade II, 15 (8.1%); Grade III, six (3.2%); Grade IV, three (1.6%); and Grade V, one (0.5%). Among cases involving screw misplacements, Grade II placement was most common, and this occurred most frequently in the middle thoracic region. CONCLUSIONS: The authors' grading system has advantages over those previously described; however, further study to determine its reliability, reproducibility, and predictive value of clinical sequelae is warranted. Postoperative CT scanning should be considered the gold standard for evaluating thoracic pedicle screw placement.

Adolescent↗

Overview of osteoporosis: pathophysiology and determinants of bone strength.

Recent advances in both the pharmacological and surgical treatment of osteoporosis and vertebral compression fractures offer exciting new options for elderly patients. However, these treatments should be considered only with an indepth knowledge of osteoporosis as a metabolic disorder with complex effects on bone, its homeostatic regulation, and vertebral strength. Bone homeostasis is under the influence of both endogenous hormonal changes and external mechanical loads resulting from physical activity. These impart their effects through regulation of the relative activities of bone cells, in particular osteoblasts and osteoclasts, which control bone deposition and resorption, respectively. The strength of a vertebra is directly influenced by the amount and relative proportions of its components, with bone mineral density a useful measure of fracture risk. The purpose of this article is to discuss these issues, among others, in order to offer the reader a better understanding of the pathophysiology of osteoporosis and the determinants of bone strength as they relate to the aging skeleton.

Aged↗

The effect of sacral fracture malreduction on the safe placement of iliosacral screws.

OBJECTIVES: To determine the effects of cranial displacement on the safe placement of iliosacral screws for zone II sacral fractures. DESIGN: Computer imaging and dimensional analysis of a human cadaveric sacral fracture model. SETTING: Cadaveric dissection, Orthopaedic Research Laboratories, Newark, New Jersey. MAIN OUTCOME MEASUREMENTS: Six cadaveric pelves with simulated zone II sacral fractures were imaged with computed tomography at controlled cranial displacements of 5, 10, 15, and 20 mm. The area of contact at the fracture site and volume of bone available for iliosacral screw placement was graphically measured using both two- and three-dimensional computer modeling. Areas of contact were also represented in terms of the maximal number of 7.0-mm screws that could be simultaneously implanted. RESULTS: Cross-sectional contact area was decreased by 30%, 56%, 81%, and 90% at 5, 10, 15 and 20 mm of displacement, respectively. Volume of bone was decreased by 21%, 25%, 26%, and 34% for 5, 10, 15 and 20 mm of displacement, respectively. In 50% of the specimens at 15 mm and 66% of the specimens with 20 mm displacement, two iliosacral screws could not be contained simultaneously within bone. In 17% of the specimens displaced 15 mm and 50% of the specimens displaced 20 mm, the cross-sectional area was insufficient to contain a single iliosacral screw. CONCLUSIONS: Although previous authors have accepted up to 15 mm of cranial displacement, the data demonstrate substantial compromise of available screw space with displacements greater than 1 cm. Fracture reduction is mandatory, as screw placement with residual displacement of 10 mm or more can endanger adjacent neural and vascular structures.

Aged↗

Circumferential fusion for spondylolisthesis in the lumbar spine.

There are many options for the surgical treatment of lumbar spondylolisthesis, including anterior and posterior techniques. Among the most versatile is a 360 degrees fusion. In consideration of the added risk of morbidity of two procedures, circumferential fusion leads to the highest fusion rates. This is particularly useful for patients at high risk for pseudarthrosis, such as patients with diabetes, posttransplant recipients, and those in whom fusion procedures have failed. Likewise, a 360 degrees fusion may also be useful in achieving fusion in biomechanically disadvantageous situations, such as at the L5-S1 level or with high-grade subluxation. The options for 360 degrees fusion are many and are determined, among other factors, by surgical pathology and surgeon preference. Standard open techniques are still considered the gold standard, although newer less invasive methods of circumferential fusion are being used more frequently. The operating surgeon must have a thorough knowledge of all available maneuvers for critical and effective decision making.

Humans↗

The mechanical effects of suture anchor insertion angle for rotator cuff repair.

Twelve matched pairs of humerii were instrumented with suture anchor at 90 degrees, 75 degrees, 45 degrees, and 30 degrees relative to the cortical border at the junction of the greater tuberosity and articular surface. Two fixtures were inserted into each specimen at different angles and loaded to failure. Suture anchors failed at an average of 171, 219, 169, and 192 N with 90 degrees, 75 degrees, 45 degrees, and 30 degrees insertion angles, respectively. No statistical difference was detected between groups (P=.08). Although previous authors have prescribed angles < or =45 degrees to improve pull-out strength, the current in vitro data does not support these recommendations.

Adult↗

History and evolution of disc replacement.

Total joint replacement has revolutionized the treatment of limb arthritides. Spinal arthroplasty is emerging as a treatment for spinal disc degeneration. The purpose of this review is to highlight the evolution of artificial interventions for nucleus and total disc replacement. This review will provide the foundation for the understanding of present and future technologies in the field.

Arthroplasty, Replacement↗

Gunshot wounds to the spine.

BACKGROUND CONTEXT: The incidence of violent crimes has risen over the past decade. With it, gunshot injuries have become increasingly more common in the civilian population. Among the most devastating injuries are gunshot wounds to the spine. PURPOSE: The purpose of this article is to provide a thorough review of the pathomechanics, diagnosis and treatment of gunshot wounds to the spine. STUDY DESIGN/SETTING: Literature review article. CONCLUSIONS: Treatment of gunshot spine fractures differs from other mechanisms. Fractures are usually inherently stable and rarely require stabilization. In neurologically intact patients, there are few indications for surgery. Evidence of acute lead intoxication, an intracanal copper bullet or new onset neurologic deficit can justify operative decompression and/or bullet removal. Overzealous laminectomy can destabilize the spine and lead to late postoperative deformity. For complete and incomplete neural deficits at the cervical and thoracic levels, operative decompression is of little benefit and can lead to higher complication rates than nonsurgically managed patients. With gunshots to the T12 to L5 levels, better motor recovery has been reported after intracanal bullet removal versus nonoperative treatment. The use of steroids for gunshot paralysis has not improved the neurologic outcome and has resulted in a greater frequency of nonspinal complications. Although numerous recommendations exist, 7 to 14 days of broad-spectrum antibiosis has lead to the lowest rates of infection after transcolonic gunshots to the spine.

Combined Modality Therapy↗

Neurovascular and tendinous damage with placement of anteroposterior distal locking bolts in the tibia.

OBJECTIVE: To determine the proximity of anteroposterior locking bolts inserted into the distal metaphyseal tibia to nearby neural, vascular, and tendinous structures. DESIGN: A cadaver study. SETTING: University trauma center. METHODS: Sixteen legs (8 matched pairs) were nailed in either neutral (Group 1) or 10 degrees of internal rotation (Group 2) and locked using one anteroposterior bolt. The anterior tibial and extensor hallucis longus tendons and neurovascular bundle were identified, and their respective locations in relation to the bolt head were measured. Average distances were calculated for each structure in each group and statistically compared. Damage to any structure was noted at final dissection. RESULTS: Average distances from the bolt head to the neurovascular bundle, extensor hallucis longus, and anterior tibial tendons were 0.6, 0.5, and 1.6 mm, respectively, for Group 1 and 1.0, 1.5, and 1.8 mm, respectively, for Group 2 legs. Statistical comparison of distances for each anatomic entity for the two groups revealed no detectable significant differences (P = 0.7, 0.4, 0.7, respectively). For all specimens, the rate of nerve, artery, extensor hallucis longus, and anterior tibial tendon injury was 25%, 19%, 0%, and 6%, respectively. However, the incidence of at least one structure damage in Group 1 legs was 63% versus 12% in Group 2 specimens (P = 0.2). CONCLUSION: Anteroposterior distal tibial locking bolts lie in close proximity to the neurovascular bundle. With standard percutaneous techniques, these structures can be damaged. Although 10 degrees of internal rotation does not statistically affect the measured distance of the locking bolt to the neurovascular bundle, it appears to decrease the incidence of neurovascular injury. This difference may best be explained by the necessary path the drill bit must take through the soft tissues to reach the underlying bone. Regardless of nail orientation, larger incisions with careful dissection and clear visualization of the anatomy are recommended to help prevent this complication.

Aged↗