Biomedical subjects

Benjamin K Potter

Publications and source records attributed to Benjamin K Potter.

At least 19 recordsLinked to original sources

PubMed2007

Missed opportunities in patients with osteoporosis and distal radius fractures.

Low-energy wrist (distal radius) fractures are hallmarks of osteoporosis. Prompt diagnosis and treatment of osteoporosis reduce refracture rates. We retrospectively determined the type and frequency of osteoporosis-related interventions rendered to patients 50 years and older in the year after a wrist fragility fracture. In addition, we compared the rates of intervention between men and women. Data were collected from the computerized medical record of one military healthcare system. We identified 111 patients who sustained wrist fragility fractures between July and December 2002. Endocrinology referrals, dual-energy xray absorptiometry scans, and osteoporosis medication prescriptions in the year after their fracture were recorded. Overall, 28 patients (25%) were referred to endocrinology, 22 patients (20%) had a dual-energy xray absorptiometry scan, 33 patients (30%) were prescribed an approved medication for treatment of osteoporosis, and 52 patients (47%) were prescribed one of these medications and/or vitamin D and calcium. Sixty percent of patients received at least one intervention. All diagnostic and medical interventions were more likely ordered for women than men. Orthopaedic surgeons continue to miss opportunities to initiate diagnostic and therapeutic interventions for patients, especially men, presenting with fragility fractures.

Absorptiometry, Photon↗

PubMed2006

Comparison of manual and digital measurements in adolescent idiopathic scoliosis.

STUDY DESIGN: Comparison of manual and digital measurement of radiographic parameters in patients with adolescent idiopathic scoliosis (AIS). OBJECTIVE: To assess the reliability of digital measures as compared to manual measures in the evaluation of AIS. SUMMARY OF BACKGROUND DATA: Radiographic parameters are critical to the evaluation of patients with AIS, and are frequently used to monitor curve progression and guide treatment decisions. The reliability of many of the more common radiographic measures has only recently been elucidated for both manual and digital measures. However, a comparative analysis of manual versus digital measures has been performed only for coronal Cobb angles. The inter-technique reliability of these parameters will have increasing importance as digital radiographic viewing and analysis become commonplace. METHODS: There were 2 independent, blinded observers that measured 30 complete sets of preoperative (posterior-anterior, lateral, and both side-bending) and postoperative (posterior-anterior and lateral) radiographs on 4 different occasions. For the first 2 iterations, manual measurements were taken using the same pencil and protractor. For the last 2 iterations, measurements of digitized radiographs were taken on a software measurement program (PhDx, Albuquerque, NM). Coronal measures included the main thoracic and thoracolumbar/lumbar standing and side-bending Cobb angles, apical vertebral translation, coronal balance, T1 tilt angle, lowest instrumented vertebrae angle, angulation of the disc inferior to the lowest instrumented vertebrae, apical Nash-Moe vertebral rotation, and Risser grade. Sagittal parameters included T2-T5 and T5-T12 regional thoracic kyphosis, T2-T12 thoracic kyphosis, T10-L2 thoracolumbar junction sagittal curvature, T12-S1 lumbar lordosis, and global sagittal balance. The technique-dependent measurement variability and the inter-technique (manual vs. digital), intraobserver reliability were evaluated for each radiographic parameter (within 3 degrees ). RESULTS: Digital measurement showed decreased intraobserver variability for many (9 of 15) of the radiographic parameters assessed. Likewise, digital measures indicated good or excellent correlation with the absolute values obtained with manual measurement for many (10 of 15) parameters. All but 1 of those parameters having moderate-to-poor correlation had been previously shown to have poor reliability, regardless of measurement technique. Statistically significant differences between measurement variability were noted for 6 measures, including 2 favoring digital and 4, manual. Significant differences in the absolute values were noted for 5 measures, determined at a difference of 3 degrees . However, the differences in both parameter variability and absolute values tended to be small and of little clinical significance for manual versus digital measurement. CONCLUSIONS: Digital measurement showed improved measurement precision and good correlation with manual measurements for the majority of AIS parameters. Absolute differences between manual and digital measurements were generally small. Therefore, digital measures are acceptable as a valid technique for scoliosis evaluation. The importance of digital versus manual measurement reliability will increase as digital radiographic viewing becomes more prevalent.

Adolescent↗

PubMed2006

Radiographic measurement techniques for sacral fractures consensus statement of the Spine Trauma Study Group.

STUDY DESIGN: Literature review. OBJECTIVES: Members of the Spine Trauma Study Group evaluated various imaging methods and compiled standardized approaches to making radiographic measurements for the assessment of sacral fractures. SUMMARY OF BACKGROUND DATA: The diagnosis of sacral fractures is frequently missed or delayed, and the treatment is controversial, with significant variations in recommendations regarding nonoperative treatment, neural decompression, and internal fixation. A paucity of specific radiographic measurements and criteria exist to aid the clinician in making sound treatment decisions. This may obligate surgeons to base clinical decisions on nonstandardized, nonvalidated recommendations and measures and, in some cases, anecdotal evidence. We think that a critical first step toward valid and optimal clinical decision-making requires an accurate and clear definition of imaging measurement parameters used to evaluate sacral injuries and gather data for future studies. METHODS: A review of the English-speaking literature was performed to assess cited radiographic measurement techniques of sacral fractures currently in use. This allowed the formulation of detailed radiographic assessments designed to more reliably describe sacral fracture morphometry. RESULTS: These measurements include: anterior-posterior sacral fracture displacement (axial computed tomography [CT] of the pelvis), vertical sacral fracture displacement (coronal CT reconstruction), anterior-posterior translation and kyphotic angulation (sagittal CT reconstructions), and degree of central canal involvement and foraminal encroachment (axial CT with fine cuts and coronal and sagittal reconstructions). Other radiographic factors that should be considered that may impact treatment outcomes include the level and type of sacral fracture, lumbosacral junction and sacroiliac joint involvement, and associated pelvic ring injury. CONCLUSIONS: With adoption of these radiographic guidelines, future studies will have a uniform method in which to describe sacral injuries and therefore allow study of the efficacy of various recommended treatment protocols.

Consensus↗

PubMed2006

Loss of coronal correction following instrumentation removal in adolescent idiopathic scoliosis.

STUDY DESIGN: Retrospective radiographic analysis of patients with adolescent idiopathic scoliosis (AIS) status after instrumentation removal. OBJECTIVE: To evaluate the effect of instrumentation removal in surgically corrected AIS. SUMMARY OF BACKGROUND DATA: Spinal instrumentation is occasionally removed for various reasons, most commonly for postoperative pain or infection, in surgically corrected AIS. The fate of instrumentation removal in adults has been previously reported with documented loss of sagittal alignment. However, to our knowledge, the long-term follow-up after instrumentation removal in AIS has not been reported. METHODS: We retrospectively reviewed the preoperative, pre-instrumentation removal, postoperative following instrumentation removal, and latest follow-up radiographs of all patients with a primary diagnosis of AIS who underwent instrumentation removal after posterior spinal fusion. There were 21 patients (15 females, 6 males) from 2 institutions, at an average age of 14.8 years (range 9-19), who were originally treated between 1988 and 2002. Instrumentation removal occurred at an average of 2.4 years after surgery (range 8 months to 4 years, 2 months), with an average follow-up of 5.2 years (range 2-11). Fifteen patients underwent removal secondary to pain (2 of these with undetected infection) and 6 for known infection. Evaluation included coronal proximal thoracic, main thoracic, thoracolumbar/lumbar (TL/L), and sagittal T2-T5, T5-T12, T2-T12, T10-L2, T12-S1, and sagittal balance before surgery, before instrumentation removal, at immediate post-removal evaluation, and at latest follow-up. RESULTS: There were 12 main thoracic curves (Lenke type 1), 6 double thoracic curves (Lenke type 2), and 3 double major curves (Lenke type 3) in the series. Average proximal thoracic curve was 19.7 degrees (range 5 degrees -35 degrees ), the main thoracic curve 63.3 (range 42 degrees -112 degrees ), and the TL-L curve averaged 31.4 degrees (range 17 degrees -53 degrees ). There was an immediate loss of approximately 4 degrees (range 0 degrees -8 degrees ) in the main thoracic curve and 6 degrees (range 1 degrees -15 degrees ) in the TL/L curve after removal, with continued settling of an additional 6 degrees (10 degrees total, P = 0.002) in the main thoracic curve, and 3 degrees in the TL/L curve (9 degrees total, P = 0.01). There was also a significant difference in the group that underwent instrumentation removal <2 years after surgery compared to >2 years (main thoracic curve 13 degrees vs. 7 degrees , P = 0.017; TL/L 11 degrees vs. 7 degrees , P = 0.036). There were no significant changes in sagittal curvature or sagittal balance in either group (P > 0.39). CONCLUSIONS: Instrumentation removal in AIS is not always a benign process because the long-term follow-up of this cohort of patients shows a "settling" effect in the coronal plane of the main thoracic and TL/L curves after instrumentation removal. Interestingly, there was no change in the sagittal plane with time. Parents and patients should be counseled for this result when instrumentation removal is contemplated, and limited removal of focally symptomatic implants should be considered.

Adolescent↗

PubMed2006

Prognostic value of magnetic resonance arthrography for Czerny stage II and III acetabular labral tears.

PURPOSE: To assess the intraobserver reliability and prognostic value of magnetic resonance arthrography (MRA) on the basis of postoperative outcome measures following arthroscopic acetabular labral debridement (partial limbectomy). METHODS: Between January 1999 and November 2000, 24 patients (13 females, 11 males) with an average age of 37.1 years (range, 21 to 56 years) underwent hip arthroscopy for the treatment of presumed acetabular labral tears. All patients underwent preoperative MRA and/or magnetic resonance imaging (MRI); images were evaluated by a single musculoskeletal radiologist on 2 independent occasions. Hip arthroscopy was performed on all patients. Outcomes were assessed by means of the Modified Harris Hip Score (MHHS) and the Short Form-36 (SF-36) questionnaires, which were completed by patients an average of 24.1 months (range, 12 to 55 months) postoperatively. The accuracy of the initial read, as well as the prognostic value of the Czerny MRA classification system for stage II (intrasubstance tears) and stage III (complete avulsions) acetabular labral tears, was assessed. RESULTS: Twenty-two of 23 tears (96%) were detected on the initial read. On the basis of intraoperative findings, 1 false-positive MRA, 1 false-negative MRA, and 1 incident of MRA overstaging were reported. On repeat interpretation, 23 of 23 (100%) tears were identified, and intraobserver reliability for recording the presence of a tear was excellent (kappa coefficient = 0.96). No difference was noted in outcomes between patients with or without arthroscopic evidence of chondromalacia (all P > .29), or between patients older or younger than 30 years (all P > .34). Likewise, no difference in outcome was seen between 15 patients with Czerny stage II tears revealed on MRA versus 9 patients with Czerny stage III tears (all P > .79). CONCLUSIONS: MRA is sensitive and accurate for the detection of acetabular labral tears, with excellent intraobserver reliability. Arthroscopic partial limbectomy is successful in two thirds of patients. Patients with Czerny stage II and III tears do not appear to have significantly different outcomes following arthroscopic labral debridement. LEVEL OF EVIDENCE: Level IV, prognostic case series.

Acetabulum↗

PubMed2006

Single-stage treatment of pyogenic spinal infection with titanium mesh cages.

STUDY DESIGN: Single institution retrospective review. OBJECTIVES: To report a series of pyogenic spinal infections treated with single-stage debridement and reconstruction with titanium mesh cages. SUMMARY OF BACKGROUND DATA: Various studies have reported surgical results of pyogenic spinal osteomyelitis with anterior debridement, strut grafting and fusion, including delayed posterior spinal instrumentation. Additionally, various authors have recommended against the use of instrumentation because of the concern about glycocalyx formation on the metal and chronic infection. At our institution, we routinely treat chronic vertebral osteomyelitis with single-stage debridement, reconstruction with a titanium mesh cage filled with allograft chips and demineralized bone matrix, and posterior pedicle screw instrumentation. To our knowledge, this is the largest single series reporting single-stage debridement and instrumentation of pyogenic spinal infection with titanium mesh cages and posterior instrumentation. MATERIALS AND METHODS: We retrospectively reviewed the patient records and radiographs of 21 consecutive patients (average age 49.3 years, range 23 to 80 years) with pyogenic vertebral osteomyelitis, all treated with titanium mesh cages. Average follow-up was 44 months (range, 25 to 70 months). Spinal levels included 6 thoracic, 4 thoracolumbar, 9 lumbar, and 2 lumbosacral (L5-S1) lesions. All patients had preoperative serum evaluation, which usually included blood cultures, complete blood count, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP), in addition to plain radiographs and magnetic resonance imaging. A positive needle biopsy was available in only 2/7 patients (29%), and overall, preoperative pathogen identification was available in only 7/21 patients (33%). All patients were treated postoperatively with a minimum of 6 weeks of intravenous antibiotics, with a specific antibiotic regimen directed toward the postoperative pathogen when identified (17/21 cases). Extensive radiographic evaluation was also performed. RESULTS: ESR and CRP were routinely elevated (18/20 and 11/17 cases respectively), whereas the white blood count was elevated in only 8 out of 21 cases (38%). The average duration of symptoms to diagnosis was approximately 13.6 weeks (range 3 weeks to 10 months). The indications for surgery included neurologic compromise, significant vertebral body destruction with loss of sagittal alignment, failure of medical treatment, and/or epidural abscess. All patients had resolution of infection, as noted by normalization of the ESR and CRP. Further, 16 out of 21 patients also had a significant reduction of pain. There were no deaths or new postoperative neurologic compromise. The most common pathogen was Staphylococcus aureus. Two patients required a second surgery (posterior irrigation and debridement) during the same admission for persistent wound drainage. Radiographically, the average segmental kyphosis (or loss of lordosis) was 11.5 degrees (range, 0 to 24 degrees) preoperatively, and +0.8 degrees (range, -3 to +5 degrees) at latest postoperative follow-up. There was an average of 2.2 mm cage settling (range, 0 to 5 mm) on latest follow-up. There were no instrumentation failures, signs of chronic infection, or rejection. CONCLUSIONS: Titanium mesh cages present a viable option for single-stage anterior surgical debridement and reconstruction of vertebral osteomyelitis, without evidence of chronic infection or rejection. When used in conjunction with pedicle screw instrumentation, there is minimal cage settling without loss of sagittal alignment.

Adult↗

PubMed2006

Amputation is not isolated: an overview of the US Army Amputee Patient Care Program and associated amputee injuries.

Rates of amputation as a percentage of all combat injuries have increased significantly since the Korean War. Following traumatic and combat-related amputation, definitive treatment and rehabilitation require a large, multidisciplinary team to provide comprehensive medical and supportive care. Associated injuries are remarkably frequent, complicating treatment and potentially delaying rehabilitation and/or limiting outcomes. Patient and family psychosocial issues also must be assessed and appropriately addressed. The US Army Amputee Patient Care Program, with the support of numerous other government and private organizations, has been developed to meet the comprehensive medical, rehabilitative, and social needs of amputees injured in the current global war on terrorism, with the goal of maximizing subsequent patient outcomes utilizing a sports medicine approach.

Amputation, Surgical↗

PubMed2006

Heterotopic ossification in the residual limbs of traumatic and combat-related amputees.

Reports on the occurrence and treatment of heterotopic ossification in amputees are rare. Heterotopic ossification in the residual limbs of amputees may cause pain and skin breakdown and complicate or prevent optimal prosthetic fitting and utilization. Basic science research has shed light on the cellular and molecular basis for this disease process, but many questions remain unanswered. The recent experience of the military amputee centers with traumatic and combat-related amputations has demonstrated a surprisingly high prevalence of heterotopic ossification in residual limbs. Primary prophylactic regimens, such as nonsteroidal anti-inflammatory drugs and local irradiation, which have proved to be effective in preventing and limiting heterotopic ossification in other patient populations, have not been studied in amputees and generally are not feasible in the setting of acute traumatic amputation. When nonsurgical measures such as activity and repeated prosthetic modifications fail to provide relief, surgical excision has provided good early clinical results, with low rates of recurrence and acceptable complication rates in military amputees.

Amputation Stumps↗

PubMed2006

Pectoralis major ruptures.

Although previously considered rare, ruptures of the pectoralis major muscle and tendon have become more common over the past 20 years with increasing participation in competitive sports and weight lifting. These injuries result from maximal eccentric contraction of the muscle with the arm held in an abducted, extended position. Most often, they occur near the tendon insertion. Complete ruptures are more common than partial tears, though many mild strains and partial tears likely go unreported or undiagnosed. Magnetic resonance imaging is the diagnostic study of choice when the diagnosis or extent of the injury is unclear. Partial tears and neglected complete tears with near complete restoration muscle strength after rehabilitation may be treated nonoperatively, with good results. Excellent results can be obtained with early anatomic repair for complete ruptures, though good results have also been reported with delayed repair of complete injuries. Early diagnosis and, when appropriate, anatomic surgical repair are the factors critical to optimizing patient outcomes after pectoralis major rupture.

Athletic Injuries↗

PubMed2006

Autologous hamstring anterior cruciate ligament reconstruction in patients older than 40.

The primary objective in this retrospective review was to assess the patient-specific outcomes and clinical utility of anterior cruciate ligament (ACL) reconstruction using the autologous quadruple-band hamstring technique in patients older than 40. Study results agree with the recent literature and demonstrate the effectiveness of an alternative to the bone-patellar tendon-bone (BPB) technique-an alternative with potentially decreased postoperative morbidity. Results also support the recent conclusion that age alone should not be a limiting factor in whether ACL reconstruction should be performed. We found that appropriately selected patients may experience significant improvements in stability, function, and pain after ACL reconstruction with the quadruple-band hamstring autograft technique. For outcomes after ACL reconstruction, there seems to be no significant difference between the sexes or between patients with and without associated injuries in this population. This study also supports use of the autologous hamstring technique as a viable option for older patients-with results similar to those of the BPB technique. The autologous hamstring technique was associated with excellent patient satisfaction and excellent functional outcome with limited postoperative morbidity. This technique may become the preferred approach for the older athlete, given its limited morbidity and equivalent clinical stability.

Adult↗

PubMed2005

Monaxial versus multiaxial thoracic pedicle screws in the correction of adolescent idiopathic scoliosis.

STUDY DESIGN: Radiographic outcome analysis following thoracic fusion of Lenke Type I adolescent idiopathic scoliosis (AIS) curves with segmental pedicle screw fixation. OBJECTIVE: To compare the correctional capacity of monaxial versus multiaxial pedicle screws in a matched cohort of AIS patients. SUMMARY OF BACKGROUND DATA: Thoracic pedicle screws provide improved curve correction over hook and wire or hybrid constructs for AIS. Further, both monaxial and multiaxial screws are available, with each offering certain advantages over the other. However, different screw types have not been evaluated against each other. METHODS: We retrospectively reviewed the preoperative and final postoperative follow-up radiographs of an age- and curve-matched cohort of 35 consecutive Lenke Type I AIS patients. Fifteen were treated with monaxial and 20 were treated with multiaxial pedicle screw constructs. All patients had a minimum 2-year follow-up. The average age at surgery was 14 years 4 months (range, 12-17 years) in the monaxial group and 13 years 8 months (12-16 years) in the multiaxial group. Evaluation included coronal proximal thoracic (PT), main thoracic (MT), and thoracolumbar/lumbar (TL/L) Cobb angles and flexibility indexes, regional sagittal curvature, the sagittal apical rib hump (RH) deformity, the apical vertebral body-rib ratio (AVB-R: ratio of linear measures from left and right apical body to lateral rib), and the apical rib spread distance (ARSD, difference of the sums of the intercostal distances at the five periapical segments measured at the lateral transverse process). RESULTS: There was no statistically significant difference with regard to the preoperative PT curves, MT curves, TL/L curves, flexibility indexes, regional sagittal curvature, AVB-R, or ARSD. The preoperative rib humps were significantly greater in the monaxial screw group (42.4 mm vs. 34.7 mm; P = 0.02). Postoperative follow-up averaged 59.9 months (range, 24-98 months) for the monaxial group and 38.0 months (range, 24-55 months) for the multiaxial group (P < 0.0001). An average of 7.7 vertebral levels were fused in the monaxial group compared with 7.2 levels in the multiaxial group (P = 0.39). After surgery, both constructs provided excellent instrumented correction of the MT curves (64.9% vs. 60.0% for the monaxial and multiaxial groups, respectively; P = 0.33), as well as good spontaneous correction of the PT (41.3% vs. 40.5%; P = 0.92) and TL/L curves (55.4% vs. 51.7%; P = 0.66). Monaxial screws demonstrated significantly greater absolute (13.9 mm vs. 25.2 mm; P < 0.0001) and relative (66.1% vs. 24.7%; P < 0.0001) correction of the apical RH. Additionally, AVB-R (77.9% vs. 54.1%; P = 0.0007) and ARSD (82.8% vs. 69.9%; P = 0.04) corrections were significantly greater in the monaxial group. There were no neurologic deficits or major complications in either group. CONCLUSION: Both monaxial and multiaxial thoracic pedicle screws provide excellent coronal deformity correction for thoracic fusion of main thoracic AIS. Monaxial screws provide superior derotation and restoration of thoracic symmetry as noted by significantly greater correction of the AVB-R, RH, and ARSD.

Adolescent↗

PubMed2005

Radiographic outcomes of anterior spinal fusion versus posterior spinal fusion with thoracic pedicle screws for treatment of Lenke Type I adolescent idiopathic scoliosis curves.

STUDY DESIGN: Analysis of radiographic outcomes following surgical correction of scoliosis. OBJECTIVES: To compare the curve correction and derotation following anterior spinal fusion (ASF) versus posterior spinal fusion (PSF) with thoracic pedicle screws. SUMMARY OF BACKGROUND DATA: The benefits of ASF in adolescent idiopathic scoliosis include saving distal fusion levels and historically greater correction and derotation compared with PSF. However, comparative studies between ASF and PSF have generally consisted only of posterior hook instrumentation or hybrid constructs, with no direct comparisons between anterior fusion and thoracic pedicle screw (TPS) series. METHODS: We performed a retrospective review of the radiographic and medical records of 40 patients (two curve-matched groups) with Lenke Type I main thoracic adolescent idiopathic scoliosis. There were 20 patients who underwent open ASF with single-rod instrumentation with a mean age at surgery of 15 years + 6 months (range, 12-20 years) and 20 patients who underwent PSF with TPS constructs with a mean age at surgery of 13 + 6 (range, 12-15). Radiographic follow-up averaged 44.1 month (24-80) for the ASF group and 55.1 month (25-83) for the PSF/TPS group. We evaluated the sagittal alignment, Cobb angles, rib hump deformity (RH), apical rib spread difference (ARSD), and apical vertebral body-rib ratio (AVB-R), measures of rotation and thoracic torsion, between both groups. RESULTS: Before surgery, the main thoracic curve was 55.1 degrees (range, 47-66 degrees) for the ASF group and 52.5 degrees (range, 46-68 degrees ) for the PSF/TPS group (P = 0.16). Additionally, there was no difference in the pelvic tilt curves, thoracic kyphosis, lumbar lordosis, RH, or ARSD. However, there was a slightly greater preoperative thoracolumbar-lumbar (TL/L) curve (34.6 degrees versus 29.5 degrees , P = 0.04) and AVB-R (1.75 versus 1.5, P = 0.003) in the ASF group. After surgery, an average of 6.5 levels (range, 6-8) were fused in the ASF group, compared with 7.7 levels (range, 5-12) in the PSF/TPS group (P = 0.001) or 1.2 additional levels for PSF/TPS. At final postoperative follow-up, spontaneous pelvic tilt curve correction was greater in the ASF group (47% versus 35%), although this difference did not reach statistical significance (P = 0.07). For the main thoracic and TL/L curves, there was greater correction in the PSF/TPS group (62% versus 52%, P = 0.009; and 56% versus 41%, P = 0.03), respectively. Additionally, the PSF/TPS group demonstrated significantly greater RH correction (51% versus 26%, P = 0.005) and AVB-R ratio improvement (73% versus 32%, P < 0.0001). We also noted a trend towards increased correction of the ARSD in the PSF/TPS group (58% versus 32%, P = 0.07). Further, the postoperative thoracic kyphosis decreased 4.4 degrees in the PSF/TPS group (postop avg. 25.0 degrees ) and increased 5.7 degrees (average, 30.6 degrees ) in the ASF group (P = 0.04). CONCLUSIONS: In this curve-matched cohort of Lenke Type I curves, PSF with TPS provided superior instrumented correction of main thoracic curves and spontaneous correction of TL/L curves. Perhaps more importantly, PSF/TPS demonstrated improved correction of thoracic torsion and rotation as compared with ASF in terms of RH (P = 0.005) and AVB-R ratio (P= 0.0001), with only one additional spinal segment fused on average.

Adolescent↗

PubMed2005

Reliability of end, neutral, and stable vertebrae identification in adolescent idiopathic scoliosis.

STUDY DESIGN: Analysis of radiographic interpretation and vertebral level identification. OBJECTIVES: To assess the intra- and interobserver reliability by observer training level used for selecting the end vertebra (EV), neutral vertebra (NV), and stable vertebra (SV) in adolescent idiopathic scoliosis patients. SUMMARY OF BACKGROUND DATA: Various radiographic and clinical factors are important in surgical planning. For adolescent idiopathic scoliosis, an analysis of the end, neutral, and stable vertebrae are of paramount importance for understanding spinal deformity management and determining the distal fusion level. Additionally, the development and comparison of optimal surgical techniques requires reliable, reproducible radiographic parameters. METHODS: One hundred consecutive radiographs of operative cases of adolescent idiopathic scoliosis were evaluated on three separate occasions by three surgeons (2700 data points) at various levels of training (fellowship-trained spine surgeon, fellow in-training, orthopedic surgery resident). For each iteration, the observers attempted to identify the distal structural Cobb curve EV, NV, and SV. The radiographs included preselected Lenke type 1, 3, and 5 curves in random order. The average main thoracic curve was 53 degrees (range, 30-82 degrees) with a T8-T9 average apex, whereas the average thoracolumbar curve was 33 degrees (range, 18-65 degrees). Intra- and interobserver reliability was assessed by means of Cohen's Kappa correlation coefficient, and raw percentages of agreement were recorded. RESULTS: Intraobserver reliability was good to excellent for determining the EV (kappaa = 0.69-0.88), good for determining the NV (kappaa = 0.65-0.73), and good to excellent for determining the SV (kappaa = 0.74-0.91) with 83.5, 72.2, and 85.6% intraobserver agreement, respectively. A trend was noted towards greater intraobserver reliability with increasing levels of observer experience. Interobserver reliability was poor (kappaa = 0.26-0.39) for each vertebral level, with interobserver agreement for only 48.7% of EV, 41.7% of NV, and 51.0% of SV. However, interobserver agreement increased significantly when concurrence within one vertebral level was assessed, with 91, 73, and 76% agreement for identifying the EV, NV, and SV, respectively. CONCLUSIONS: Radiographic determination of the EV, NV, and SV demonstrated good to excellent intraobserver, but poor interobserver, reliability. Interobserver agreement was fair to good when concurrence within one adjacent level was assessed. Observer experience level may be a factor. The difficulties in identifying these vertebral levels represent a potential obstacle to reproducible patient-specific fusion level determination and to the optimization and uniformity of patient care.

Adolescent↗

PubMed2005

Correlation of Short Form-36 and disability status with outcomes of arthroscopic acetabular labral debridement.

BACKGROUND: Arthroscopic debridement is the standard of care for the treatment of acetabular labral tears. The Short Form-36 has not been used to measure hip arthroscopy outcomes, and the impact of disability status on hip arthroscopy outcomes has not been reported. HYPOTHESIS: Short Form-36 subscale scores will demonstrate good correlation with the modified Harris hip score, but patients undergoing disability evaluation will have significantly worse outcome scores. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: The records of active-duty soldiers who underwent hip arthroscopy at the authors' institution were retrospectively reviewed. Forty consecutive patients who underwent hip arthroscopy for the primary indication of labral tear formed the basis of the study group. Patients completed the modified Harris hip score, the Short Form-36 general health survey, and a subjective overall satisfaction questionnaire. RESULTS: Thirty-three patients, with a mean age of 34.6 years, were available for follow-up at a mean of 25.7 months postoperatively. Fourteen (43%) patients were undergoing medical evaluation boards (military equivalent of workers' compensation or disability claim). Pearson correlation coefficients for comparing the Short Form-36 Bodily Pain, Physical Function, and Physical Component subscale scores to the modified Harris hip score were 0.73, 0.71, and 0.85, respectively (P < .001). The mean modified Harris hip score was significantly lower in patients on disability status than in those who were not (92.4 vs 61.1; P < .0001). The Short Form-36 subscale scores were significantly lower in disability patients (P < .02). Patient-reported satisfaction rates (70% overall) were 50% for those undergoing disability evaluations and 84% for those who were not (P < .04). There was no significant difference in outcomes based on patient age, surgically proven chondromalacia, or gender for military evaluation board status. CONCLUSION: The Short Form-36 demonstrated good correlation with the modified Harris hip score for measuring outcomes after arthroscopic partial limbectomy. Arthroscopic debridement yielded a high percentage of good results when patients undergoing disability evaluations were excluded. Disability status may be a negative predictor of success after hip arthroscopy.

Acetabulum↗

PubMed2005

Reliability analysis for manual adolescent idiopathic scoliosis measurements.

STUDY DESIGN: Manual radiographic measurement analysis. OBJECTIVES: To determine the intraobserver and interobserver reliability of numerous radiographic process measures used in the assessment of adolescent idiopathic scoliosis. SUMMARY OF BACKGROUND DATA: Analysis of scoliosis requires a thorough radiographic evaluation to completely assess the deformity. Numerous radiographic process measures have been studied extensively and used for outcomes assessment and thus become the de facto standard of care. However, many of these measures have not been evaluated to determine the reliability and reproducibility. Validation of radiographic process measures is necessary to compare these measures with patient-focused outcome measures, as well as to permit valid comparison of different surgical techniques. METHODS: Thirty complete sets of long-cassette scoliosis radiographs (anteroposterior [AP], lateral and side-bending preoperative and AP, and lateral postoperative) were analyzed by three independent experienced observers on two separate occasions. Coronal image measures included the coronal Cobb angles, side-bending Cobb, apical vertebral translation, coronal balance, T1 tilt, lowest instrumented vertebrae (LIV) tilt, angulation of the disc below the LIV, apical vertebral rotation (Nash-Moe),and Risser sign; sagittal measures included T2-T5, T5-T12, T2-T12, T10-L2, T12-S1, and sagittal balance. Intraobserver and interobserver reliability for each measure was then assessed. RESULTS: The vast majority of the radiographic process measures assessed demonstrated good to excellent or excellent intraobserver and interobserver reliability. However, the angulation of the disc below the LIV demonstrated only fair interobserver reliability for postoperative measurements (rho = 0.59). Likewise, Risser grade measurements reflected good intraobserver (0.81-0.99) but only fair interobserver reliability (0.60-0.70). Apical vertebral rotation assessed by the technique of Nash and Moe produced good intraobserver reliability before surgery (0.74-0.85) but only fair reliability after surgery (0.50-0.85). The interobserver reliability for apical Nash-Moe rotation was fair to poor (0.53-0.59). For T2-T5 regional kyphosis, intraobserver (0.22-0.83) and interobserver (0.33-0.47) reliability was generally poor. Overall, the reliability of postoperative measurements tended to be decreased relative to preoperative values, likely due to instrumentation overlying radiographic landmarks. CONCLUSIONS: Most of the radiographic process measures evaluated in this study demonstrated good or excellent reliability. The reliability of measuring the angulation of the disc below the LIV, the apical Nash-Moe rotation, and Risser grading was decreased relative to other measures. The reliability of measuring T2-T5 regional kyphosis was disappointing and poor. With regards to the other 13 measures assessed, our findings support the use of these process measures obtained by experienced deformity surgeons via manual measurement for routine clinical and academic purposes.

Adolescent↗

PubMed2005

Reliability analysis for digital adolescent idiopathic scoliosis measurements.

OBJECTIVE: Analysis of adolescent idiopathic scoliosis (AIS) requires a thorough clinical and radiographic evaluation to completely assess the three-dimensional deformity. Recently, these radiographic parameters have been analyzed for reliability and reproducibility following manual measurements; however, most of these parameters have not been analyzed with regard to digital measurements. The purpose of this study is to determine the intra- and interobserver reliability of common scoliosis radiographic parameters using a digital software measurement program. METHODS: Thirty sets of preoperative (posteroanterior [PA], lateral, and side-bending [SB]) and postoperative (PA and lateral) radiographs were analyzed by three independent observers on two separate occasions using a software measurement program (PhDx, Albuquerque, NM). Coronal measures included main thoracic (MT) and thoracolumbar-lumbar (TL/L) Cobb, SB MT Cobb, MT and TL/L apical vertical translation (AVT), C7 to center sacral vertical line (CSVL), T1 tilt, LIV tilt, disk below lowest instrumented vertebra (LIV), coronal balance, and Risser, whereas sagittal measures included T2-T5, T5-T12, T2-T12, T10-L2, T12-S1, and sagittal balance. Analysis of variance for repeated measures or Cohen three-way kappa correlation coefficient analysis was performed as appropriate to calculate the intra- and interobserver reliability for each parameter. RESULTS: The majority of the radiographic parameters assessed demonstrated good or excellent intra- and interobserver reliability. The relationship of the LIV to the CSVL (intraobserver kappaa = 0.48-0.78, fair to excellent; interobserver kappaa = 0.34-0.41, fair to poor), interobserver measurement of AVT (rho = 0.49-0.73, low to good), Risser grade (intraobserver rho = 0.41-0.97, low to excellent; interobserver rho = 0.60-0.70, fair to good), intraobserver measurement of the angulation of the disk inferior to the LIV (rho = 0.53-0.88, fair to good), apical Nash-Moe vertebral rotation (intraobserver rho = 0.50-0.85, fair to good; interobserver rho = 0.53-0.59, fair), and especially regional thoracic kyphosis from T2 to T5 (intraobserver rho = 0.22-0.65, poor to fair; interobserver rho = 0.33-0.47, low) demonstrated lesser reliability. In general, preoperative measures demonstrated greater reliability than postoperative measures, and coronal angular measures were more reliable than sagittal measures. CONCLUSIONS: Most common radiographic parameters for AIS assessment demonstrated good or excellent reliability for digital measurement and can be recommended for routine clinical and academic use. Preoperative assessments and coronal measures may be more reliable than postoperative and sagittal measurements. The reliability of digital measurements will be increasingly important as digital radiographic viewing becomes commonplace.

Adolescent↗

PubMed2005

Vertebral rotation and thoracic torsion in adolescent idiopathic scoliosis: what is the best radiographic correlate?

BACKGROUND: As a result of the increased appreciation of the three-dimensional nature of scoliosis and modern spinal instrumentation's improved corrective capabilities, there has been renewed interest in the correction and measurement of vertebral rotation. Computed tomography (CT), the gold standard for accuracy, is limited in its clinical utility owing to cost, radiation exposure, and the effects of postural changes on scoliosis curves and vertebral rotation. Consequently, the Perdriolle and Nash-Moe techniques remain the standard measurements for providing a reasonable estimate of pre- and postoperative vertebral rotation because of their simplicity. However, these techniques have considerable interobserver variability, and pedicle screw instrumentation obscures the landmarks necessary for utilizing these techniques for postoperative vertebral rotation assessment. The purpose of the present study was to assess the utility of alternate radiographic measures to assess vertebral rotation and thoracic torsion when compared with conventional measures on pre- and postoperative radiographs and CT evaluation. METHODS: We reviewed the preoperative, immediate postoperative, and final follow-up radiographs, as well as the pre- and postoperative CT scans, of 19 patients (average age 15 years, 6 months) with Lenke 1 curves (average 55 degrees , range 47-66 degrees ), all treated with anterior spinal fusion. Coronal and sagittal Cobb angles as well as vertebral rotation (Perdriolle and Nash-Moe) at the superior uninstrumented, superior instrumented, apical, inferior instrumented, and inferior uninstrumented vertebrae were measured on all films, and vertebral rotation was assessed on the CT scans by a previously described method. Additionally, several measures of thoracic torsion (as a proxy for vertebral rotation and overall deformity improvement) were assessed. These included the rib-vertebral angle difference (RVAD), apical rib hump prominence (RH), apical vertebral body-rib ratio (AVB-R), and apical rib spread difference (ARSD). RESULTS: The postoperative main thoracic curve averaged 26 degrees (range 16-39 degrees , 52% correction) and 29 degrees (range 22-40 degrees , 47% correction) at final follow-up. For apical derotation, the postoperative CT improved from -11.5 degrees to -6.6 degrees and correlated significantly with the Cobb main thoracic curves (42% correction, r = 0.48, P = 0.003). There was weakly positive, but statistically significant, correlation between the pre- and postoperative CT scans and the corresponding Perdriolle and Nash-Moe measures of segmental rotation (r = 0.32-0.40, all P < 0.0001). The RVAD demonstrated poor correlation with the main thoracic curve values and correction, Perdriolle rotation and correction, and CT rotation and correction (r = -0.22-0.37, all P > 0.20). The apical RH demonstrated good correlation with the main thoracic curve (r = 0.65, P < 0.0001), apical Perdriolle rotation (r = 0.57, P < 0.0001), and CT apical rotation (r = 0.53, P = 0.002). We also found moderate correlation between the AVB-R and the main thoracic Cobb, apical Perdriolle, and CT (r = 0.57, 0.59, and 0.49, respectively; all P < 0.005). Similar relationships were found with the ARSD (r = 0.51, 0.47, and 0.43, respectively; all P < 0.02). CONCLUSIONS: The RH, AVB-R, and the ARSD-measures of thoracic torsion-demonstrated moderate to good overall correlation with the main thoracic curve Cobb angles, apical Perdriolle rotation, and apical CT rotation. These should be useful as clinical measures for assessing three-dimensional deformity correction on plane radiographs, especially for the intraoperative evaluation of vertebral derotation and thoracic symmetry restoration.

Adolescent↗

PubMed2005

Transforaminal lumbar interbody fusion: clinical and radiographic results and complications in 100 consecutive patients.

OBJECTIVE: We retrospectively reviewed the results of 100 consecutive transforaminal lumbar interbody fusions (TLIFs) performed at one institution. The preoperative diagnoses included degenerative disk disease (55), spondylolisthesis (41; 22 isthmic, 19 degenerative), and degenerative adult scoliosis (4). There were 64 single-level, 33 two-level, 2 three-level, and 1 four-level TLIF (140 levels). METHODS: The fusion mass was assessed by an independent observer using biplanar radiography, whereas clinical outcomes were assessed by means of several established outcome measures. RESULTS: By level, the posterolateral fusion was judged to be probably or definitely solid in 78% of levels, whereas the interbody fusion was radiographically solid in 88% of levels, for an overall 93% fusion success/patient (94%/level). All patients had >24 months of postoperative clinical follow-up, and 82 patients (82%) were available for outcome measure assessment at an average follow-up of 34 months (range 24-61 months) postoperatively. Eighty-one percent of these patients reported a >50% decrease in their symptoms, and 76% of patients were satisfied with their results to the degree that they would have the procedure again. However, a large percentage of patients experienced incomplete relief of their symptoms. Twenty patients sustained minor complications, and there were no major complications. CONCLUSIONS: We conclude that TLIF is a safe and effective method of achieving lumbar fusion with a 93% radiographic fusion success and a nearly 80% rate of overall patient satisfaction but frequently results in incomplete relief of symptoms. Complications resulting from the procedure are uncommon and generally minor and transient.

Adult↗