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Treatment of long bone nonunions: factors affecting healing
Egol, Kenneth A; Bechtel, Christopher; Spitzer, Allison B; Rybak, Leon; Walsh, Michael; Davidovitch, Roy
PURPOSE: Nonunions of the upper and lower extremity have been associated with pain and functional deficits. Recent studies have demonstrated that healing of these nonunions is associated with pain relief and both subjective and objective functional improvement. The purpose of this study was to determine which patient and surgical factors correlated with successful healing of a nonunion following surgical intervention. METHODS: Between September 2004 and February 2008, all patients with a "long bone nonunion" presenting to our academic trauma service were enrolled in a prospective data base. Baseline functional, demographic and pain status was obtained. Follow-up was obtained at 3, 6, and 12 months following surgical intervention, with longer follow-up as possible. One hundred and thirty-four patients with a variety of fracture nonunions were operated on by four different fellowship trained trauma surgeons with experience ranging from 2 to 15 years and variable nonunion surgery loads. Patients were stratified into one of three groups: 1. Patients who healed following one surgical intervention, 2. those who healed following multiple surgical intervention, and 3. those who failed to heal (remain ununited or underwent amputation). Healing was determined radiographically and clinically. Complications were recorded. Logistic regression analysis was performed to assess the cor-relation between specific baseline and surgical characteristics and healing. RESULTS: A minimum of 1 year follow-up was available for all 134 patients. One hundred and one patients (76%) with a mean age of 50 years healed at a mean of 6 months (range, 3 to 16) after one surgery. Twenty-two patients (16%) with a mean age of 47 years, who required more than one intervention, healed their nonunions at a mean of 11 months (range, 4 to 23). Eleven patients (8%) with a mean age of 50 years failed to heal at an average of 12 months follow-up. Complication rates were 11%, 68%, and 100% respectively for those who healed following one procedure, multiple procedures, and those who never healed. Higher surgeon volume (greater than 10 cases per year) was associated with 85% increased healing rates (OR = 0.15, 0.05-0.47 CI). The presence of a postoperative complication was associated with a 9 times lower likelihood of successful union as well (OR = 9.0, 2.6-31.7 CI). Patient age, sex, BMI, initial injury mechanism, tobacco use, and initial injury characteristics did not correlate with failure to heal. CONCLUSION: Our data is similar to other studies assessing outcomes following other complex reconstructive procedures. It appears that more experienced (higher volume) reconstructive surgeons and the development of fewer postoperative complications is associated with greater success following repair of a long bone nonunion. Infection at any point during treatment is associated with failure to achieve successful union.
PMID: 23267445
ISSN: 1936-9719
CID: 216162
"Incidental" bone lesions--when to refer to the tumor specialist
Kim, L T Suezie; Laible, Catherine N; Rybak, Leon D; Rapp, Timothy B
Incidental bone tumors are, by definition, asymptomatic lesions that are discovered through routine radiographs obtained for other reasons. Generally, these lesions are benign and latent, requiring no further intervention except observation. However, occasionally these radiographs will detect benign aggressive processes or even malignant lesions that do require further treatment and referral to a tumor specialist. Oftentimes, there are characteristic findings on radiographs that are pathognomonic. Knowledge of these findings can simplify the treatment algorithm for a practicing general orthopaedist. This article will describe radiographic characteristics of benign and malignant bone lesions and their typical presentations. It will then focus on the types of bone lesions that are often found incidentally by routine radiography. Specific recommendations, including recommendation for referrals to orthopaedic tumor specialists, will be noted for lesions described. Most malignant lesions will present with pain and a constellation of history and physical exam findings that will signal the patient to seek medical care; although they will be mentioned for the sake of comparison and completeness, they will not be the focus of this review.
PMID: 23267447
ISSN: 1936-9719
CID: 216152
Neurogenic pelvic pain and denervation syndromes: Differential diagnosis with emphasis on cross sectional imaging [Meeting Abstract]
Delaney, H; Bencardino, J T; Bonder, J; McGorty, K; Rybak, L
Purpose: To review the potential etiologies of neurogenic pelvic pain and to describe diagnostic features with a particular emphasis on lesions detected by cross sectional imaging. Materials and Methods: A retrospective review of cases presenting with pelvic neurogenic pain during the past 3 years was performed at our institution using our hospital data search engine. All patients had undergone cross sectional imaging, including dedicated pelvic MR neurography. The study group was classified according to location of involvement including: 1) obturator neuropathy, 2) femoral neuropathy, 3) pudendal neuropathy, 4) superior gluteal neuropathy and 5) piriformis syndrome. The presence of associated denervation muscle changes was recorded. Cases were further characterized by etiology into: 1) Space occupying lesions, 2) Iatrogenic and 3) Post traumatic. A review of the literature was performed and the findings are presented in a pictorial fashion with case by case illustration. Results: Twenty-four cases were collected. Of these, 6 patients had symptoms of pelvic neurogenic pain with no apparent imaging findings. Eight patients had radiological evidence of possible obturator nerve compression, 1 patient had findings suggestive of obturator nerve injury, 2 patients had radiological evidence of piriformis syndrome, and 2 patients each had radiological evidence of pudendal and femoral nerve involvement. Two patients had multiple sites of involvement. A wide variety of space occupying lesions were found including neurogenic lesions, perineural cysts, ganglion cysts, malignant tumors, and fluid distended bursae. Impingement related to post surgical changes following hip arthroplasty and related to prior pelvic fracture was also identfied. Denervation muscle changes were noted in several patients, including in patients with no radiologically detectable lesion. Conclusion: There are multiple potential etiologies for neurogenic pelvic pain. Clinical localization of symptoms as well as knowledge of the pelvic neural anatomy is of critical importance in the search for an underlying etiology. Muscle denervation changes are a very useful secondary sign of pelvic neuropathy particularly in the absence of a detectable compressive etiology on MR imaging
EMBASE:70845256
ISSN: 0364-2348
CID: 177079
Accuracy of detecting screw penetration of the radiocarpal joint following volar plating using plain radiographs versus computed tomography
Takemoto, Richelle C; Gage, Mark; Rybak, Leon; Zimmerman, Igor; Egol, Kenneth A
We compared standard and specialized plain radiographs with computed tomography (CT) for their ability to detect screw penetration of the articular surface of the distal radius in volar plating. Eight human cadaveric specimens were implanted with a fixed angle volar plate and 5 screws. Two groups were evaluated: (1) no articular screw penetration or (2) intra-articular screw penetration. Radiographs were obtained of each specimen. CT using 0.4 mm thickness slices were obtained and images were reconstructed in the sagittal and coronal planes. The radiographs and CTs were evaluated based on whether or not articular penetration occurred. The sensitivity, specificity, and accuracy of each radiographic modality were evaluated. CT was found to be much more sensitive and specific in detecting screw penetration than plain radiographs. The kappa (kappa) statistic demonstrated "almost perfect interobserver agreement" based on CT readings, but only "substantial interobserver agreement based on plain radiographs." CT is more sensitive and specific and achieves a higher kappa statistic than plain radiographs in detecting radiocarpal screw penetration after volar plating. CT should be used in detecting screw penetration when there is suspicion for radiocarpal joint penetration.
PMID: 22900246
ISSN: 1078-4519
CID: 175789
Preliminary Study of 1.5-T MR Arthrography of the Shoulder With 3D Isotropic Intermediate-Weighted Turbo Spin Echo
Rybak, Leon D; La Rocca Vieira, Renata; Recht, Michael; Shepard, Timothy; Wiggins, Graham; Babb, James; Glaser, Christian
OBJECTIVE: The purpose of this study was to assess the performance of a near-isotropic 3D turbo spin-echo sequence in comparison with a standard 2D protocol and with arthroscopy in direct 1.5-T MR arthrography of the shoulder. SUBJECTS AND METHODS: Dilute gadolinium was injected into three cadaver shoulders, and 3D turbo spin-echo and 2D sequences were evaluated with respect to the signal-to-noise and contrast-to-noise ratios of key tissues. In a prospective study, the 3D intermediate-weighted fat-suppressed sequence (reformatted in three planes) was added to shoulder MR arthrography of 43 consecutively registered patients, 13 of whom later underwent arthroscopy. Two radiologists independently graded the 3D and 2D images in separate sessions to visualize normal anatomic features and to detect pathologic changes in the labrum, cartilage, cuff, and glenohumeral ligaments, assigning confidence levels to their readings. One reader repeated the readings of images of 10 patients. Reports of subsequent arthroscopy were available for 13 patients. RESULTS: The sequences performed comparably with respect to signal-to-noise and contrast-to-noise ratios in the cadavers. The 3D images suffered from mildly increased blurring, but the readers were significantly more confident in assessing the proximal biceps tendon and curved portions of the labrum and in their findings of partial tears of the articular side of the supraspinatus tendon and posterior labral tears on the 3D images. A larger number of partial-thickness cartilage defects were found on 2D images. CONCLUSION: The 3D turbo spin-echo sequence is a promising technique that can be used in shoulder arthrography with image quality and results comparable to those of traditional 2D techniques. Use of the 3D technique may result in greater anatomic detail in evaluating small obliquely oriented structures, including the curved portions of the labrum and the intraarticular portion of the biceps tendon.
PMID: 22733918
ISSN: 0361-803x
CID: 170437
Technical update on magnetic resonance imaging of the shoulder
La Rocca Vieira, Renata; Rybak, Leon D; Recht, Michael
Improvement in both hardware and software has opened up new opportunities in magnetic resonance (MR) imaging of the shoulder. MR imaging at 3-T has become a reality, with the prospect of 7-T imaging on the horizon. The art of MR arthrography continues to improve, aided by the use of novel imaging positions. New techniques for three-dimensional imaging, the reduction of metal artifact, and biochemical imaging of cartilage hold great promise.
PMID: 22469396
ISSN: 1064-9689
CID: 163581
Hand Osteoarthritis: A Predictor of Accelerated Progression in Knee OA? [Meeting Abstract]
Samuels, Jonathan; Petchprapa, Catherine; Carpenter, Elizabeth; Attur, Mukundan; Rybak, Leon; Krasnokutsky, Svetlana; Oh, Cheongeun; Abramson, Steven B
ISI:000297621501264
ISSN: 0004-3591
CID: 2331102
Rupture of the distal biceps tendon combined with a supinator muscle tear in a 51-year-old woman: a case report
Nayyar, Samir; Quirno, Martin; Hasan, Saqib; Rybak, Leon; Meislin, Robert J
Distal biceps tendon rupture is a relatively uncommon occurrence in the general female population, and to our knowledge, has not been reported in association with a supinator muscle tear. We report a case of 51-year-old woman who experienced sharp pain in her forearm and elbow after lifting a heavy object. History and physical examination raised suspicion for a distal biceps tendon rupture. MRI imaging determined a combined distal biceps tendon tear with a supinator muscle tear with subsequent confirmation at surgery. Surgical repair was performed for the distal biceps tendon only through a single incision approach using the Endobutton technique.
PMCID:3350064
PMID: 22606548
ISSN: 2090-6870
CID: 167505
Clear cell sarcoma of soft tissue involving the elbow joint
Smilowitz N.R.; Villalobos C.E.; Rybak L.D.; Wittig J.C.
EMBASE:2011262162
ISSN: 1940-7041
CID: 133419
Bisphosphonate-related complete atypical subtrochanteric femoral fractures: diagnostic utility of radiography
Rosenberg, Zehava Sadka; La Rocca Vieira, Renata; Chan, Sarah S; Babb, James; Akyol, Yakup; Rybak, Leon D; Moore, Sandra; Bencardino, Jenny T; Peck, Valerie; Tejwani, Nirmal C; Egol, Kenneth A
OBJECTIVE: The objective of our study was to evaluate the diagnostic utility of conventional radiography for diagnosing bisphosphonate-related atypical subtrochanteric femoral fractures. MATERIALS AND METHODS: Retrospective interpretation of 38 radiographs of complete subtrochanteric and diaphyseal femoral fractures in two patient groups-one group being treated with bisphosphonates (19 fractures in 17 patients) and a second group not being treated with bisphosphonates (19 fractures in 19 patients)-was performed by three radiologists. The readers assessed four imaging criteria: focal lateral cortical thickening, transverse fracture, medial femoral spike, and fracture comminution. The odds ratios and the sensitivity, specificity, and accuracy of each imaging criterion as a predictor of bisphosphonate-related fractures were calculated. Similarly, the interobserver agreement and the sensitivity, specificity, and accuracy of diagnosing bisphosphonate-related fractures (i.e., atypical femoral fractures) were determined for the three readers. RESULTS: Among the candidate predictors of bisphosphonate-related fractures, focal lateral cortical thickening and transverse fracture had the highest odds ratios (76.4 and 10.1, respectively). Medial spike and comminution had odd ratios of 3.8 and 0.63, respectively. Focal lateral cortical thickening and transverse fracture were also the most accurate factors for detecting bisphosphonate-related fractures for all readers. The sensitivity, specificity, and overall accuracy for diagnosing bisphosphonate-related fractures were 94.7%, 100%, and 97.4% for reader 1; 94.7%, 68.4%, and 81.6% for reader 2; and 89.5%, 89.5%, and 89.5% for reader 3, respectively. The interobserver agreement was substantial (kappa > 0.61). CONCLUSION: Radiographs are reliable for distinguishing between complete femoral fractures related to bisphosphonate use and those not related to bisphosphonate use. Focal lateral cortical thickening and transverse fracture are the most dependable signs, showing high odds ratios and the highest accuracy for diagnosing these fractures
PMID: 21940585
ISSN: 1546-3141
CID: 137889