J. Sebastiaan Souer
Harvard University
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Featured researches published by J. Sebastiaan Souer.
Journal of Bone and Joint Surgery, American Volume | 2009
J. Sebastiaan Souer; David Ring; Stefan Matschke; Laurent Audige; Marta Marent-Huber; Jesse B. Jupiter
BACKGROUND The impact of an unrepaired fracture of the ulnar styloid base on recovery after internal fixation of a fracture of the distal part of the radius is uncertain. We evaluated a series of patients with an internally fixed fracture of the distal part of the radius to test the hypothesis that there is no difference in wrist motion or function scores between those with an untreated fracture of the ulnar styloid base and those with no ulnar fracture. METHODS Two cohorts of seventy-six matched patients, one with a fracture of the ulnar styloid base and the other with no ulnar fracture, were retrospectively analyzed by examining data gathered in a prospective study of plate-and-screw fixation of distal radial fractures. Patients were matched for age, sex, AO fracture type, and injury mechanism. The two cohorts were analyzed for differences in motion, grip strength, pain, the Gartland and Werley score, the DASH (Disabilities of the Arm, Shoulder and Hand) score, and the SF-36 (Short Form-36) score at six, twelve, and twenty-four months postoperatively. In a second analysis, sixty-four patients with <2 mm of displacement of a fracture of the ulnar styloid base were compared with forty-nine patients with greater displacement. Differences between cohorts and within cohorts over time were determined with use of regression analysis and the likelihood ratio test. RESULTS No significant differences were found between patients with an unrepaired fracture of the ulnar styloid base and those with no ulnar fracture at any of the follow-up intervals. However, a trend was observed toward less grip strength at six months (71% [of that on the contralateral side] compared with 79%; mean difference, -8% [95% confidence interval=-15.3% to -0.6%]; p=0.03) and less flexion (54 degrees compared with 59 degrees ; mean difference, -5 degrees [95% confidence interval=-11.7 degrees to -0.8 degrees ]; p=0.02) and ulnar deviation (32 degrees compared with 36 degrees ; mean difference, -4 degrees [95% confidence interval=-7 degrees to -0.1 degrees ]; p=0.05) at twenty-four months after surgery in patients with an untreated fracture of the ulnar styloid base. There were no significant differences with regard to any tested outcome measure between the patients with >or=2 mm of displacement of an unrepaired fracture of the ulnar styloid base and those with less displacement. CONCLUSIONS An unrepaired fracture of the base of the ulnar styloid does not appear to influence function or outcome after treatment of a distal radial fracture with plate-and-screw fixation, even when the ulnar fracture was initially displaced >or=2 mm.
Hand | 2008
Santiago A. Lozano-Calderon; J. Sebastiaan Souer; Jesse B. Jupiter; David Ring
Among 44 consecutive patients electing operative treatment of trapeziometacarpal arthrosis, three age- and gender-matched controls that presented during the same time period but had not yet requested operative treatment were selected from billing records. Each patient and control was mailed a survey that included an upper extremity-specific health status measure (Disabilities of the Arm, Shoulder, and Hand questionnaire; DASH) and a set of questionnaires evaluating psychological factors including the Pain Anxiety Symptoms Scale (PASS), the Pain Catastrophizing Scale (PCS) and the Center for the Epidemiological Study of Depression (CES-D) instrument. Seventy-two patients (45%; 31 that elected operative and 41 nonoperative care) returned a completed questionnaire with usable data. Older age was the only significant predictor of choice for nonoperative treatment among survey responders. Arm-specific disability (DASH) correlated with the CES-D, PASS, and PCS scores, and the influence of radiographic severity was near significant (p = 0.06). Stepwise multiple linear regression resulted in a model including the CES-D and PCS scores and accounting for 51% of the variability in DASH scores for patients from both cohorts. For both the operative and nonoperative cohorts, a model including CES-D alone accounted for 50% of the variability in DASH scores (p < 0.01). This study suggests that depression, pain anxiety, and pain catastrophizing are strong correlates of arm-specific disability but do not predict election of operative treatment in patients with trapeziometacarpal arthrosis.
Journal of Hand Surgery (European Volume) | 2010
J. Sebastiaan Souer; David Ring; Stefan Matschke; Laurent Audige; Marta Maren-Hubert; Jesse B. Jupiter
PURPOSE Open reduction and locked volar plate and screw fixation is a popular treatment method for extra-articular distal radius fractures with dorsal metaphyseal comminution. In this study, we compared the use of a titanium 2.4-mm precontoured plate with that of a stainless-steel oblique 3.5-mm T-shaped plate to test the null hypothesis that there would be no difference in wrist function or upper extremity-specific health status in the internal fixation of AO-type A3.2 distal radius fractures. METHODS We retrospectively analyzed 24 patients treated with a 2.4-mm titanium plate and 38 patients treated with a 3.5-mm stainless-steel plate for an extra-articular and dorsally angulated distal radius fracture, from data gathered in a prospective cohort study of plate and screw fixation of distal radius fractures. The 2 cohorts were analyzed for differences in motion, grip strength, pain, Gartland and Werley score, Disabilities of the Arm, Shoulder, and Hand score, and Short Form-36 score at 6, 12, and 24 months of follow-up. Group differences and their change over time were determined using regression analysis and the likelihood ratio test. RESULTS There were no significant differences in wrist function and arm-specific health status between patients treated with a 2.4-mm plate and those treated with a 3.5-mm plate at 6, 12, or 24 months of follow-up. However, we observed a trend toward greater wrist flexion at 1 year (66 degrees vs 55 degrees ; p=.07) and greater flexion-extension arc (137 degrees vs 123 degrees ; p=.08) and pronation-supination arc (172 degrees vs 160 degrees ; p=.07) at 24 months after surgery in patients treated with a 2.4-mm plate. CONCLUSIONS Patients with a dorsally angulated extra-articular distal radius facture can expect similar results when treated with either a precontoured 2.4-mm titanium plate or a 3.5-mm stainless-steel T-shaped plate. TYPE OF STUDY/LEVEL OF EVIDENCE Therapeutic III.
Journal of Bone and Joint Surgery, American Volume | 2009
J. Sebastiaan Souer; David Ring; Jesse B. Jupiter; Stefan Matschke; Laurent Audige; Marta Marent-Huber
BACKGROUND Fractures of the volar articular margin of the distal part of the radius with volar radiocarpal subluxation (volar shearing, or Barton, fractures) can be accompanied by a fracture of the dorsal metaphyseal cortex. We tested the null hypothesis that there is no difference in wrist function or health status after open reduction and plate-and-screw fixation between volar shearing fractures with a dorsal cortical fracture (complete articular, AO Type C) and those without a dorsal cortical fracture (partial articular, AO Type B). METHODS In a multicenter cohort study, fifty-seven patients with a volar marginal shearing fracture of the distal part of the radius and volar radiocarpal subluxation were followed for at least one year following plate-and-screw fixation. Thirty-seven patients who also had a dorsal metaphyseal cortical fracture (Type-C fracture) were compared with twenty patients who had a partial articular (Type-B) fracture. The two cohorts were analyzed for differences in wrist and forearm motion, grip strength, pain, and the Gartland and Werley, Disabilities of the Arm, Shoulder and Hand (DASH), and Short Form-36 (SF-36) scores at six, twelve, and twenty-four months postoperatively. Differences in mean values and their change over time were determined. RESULTS There were no significant differences between patients with a Type-B fracture and those with a Type-C fracture with respect to motion, grip strength, or the Gartland and Werley or DASH score at any time point. At six months after the surgery, the patients with a Type-B volar shearing fracture reported a mean score for pain in motion of 0.5 point on a 10-point visual analogue scale compared with 2.2 points for patients with a Type-C fracture (difference in means, 1.7 points [95% confidence interval, 0.7 to 2.6 points]; p < 0.001), but no significant difference was seen at twelve or twenty-four months. CONCLUSIONS Volar shearing fractures are usually complete articular, Type-C injuries. Patients with a Type-C volar shearing fracture experience more pain during early recovery, but ultimately their outcome is comparable with that for patients with a Type-B (partial articular) volar shearing fracture.
Journal of Hand Surgery (European Volume) | 2009
Eric Fu; Guoan Li; J. Sebastiaan Souer; Santiago A. Lozano-Calderon; James H. Herndon; Jesse B. Jupiter; Neal C. Chen
PURPOSE Previous in vivo and in vitro studies of forearm supination-pronation suggest that distal radioulnar joint kinematics may be affected by elbow flexion. The primary hypotheses tested by this study were that, in vivo, ulnar variance changes with elbow flexion and forearm rotation, and the arc of forearm rotation changes in relationship to elbow flexion. METHODS Changes in radioulnar kinematics during forearm supination-pronation and elbow flexion (0 degrees to 90 degrees ) were studied in 5 uninjured subjects using computed tomography, dual-orthogonal fluoroscopy, and 3-dimensional modeling. Analysis of variance and post-hoc testing was performed. RESULTS Proximal translation of the radius was greatest with the elbow flexed to 90 degrees with the arm in midpronation. With the arm in midpronation, the translation of the radius was significantly greater at 0 degrees versus 45 degrees of elbow flexion (0.82 +/- 0.59 mm vs 0.65 +/- 0.80 mm, F: 4.49, post hoc: 0.055; p = .05) and significantly smaller at 45 degrees versus 90 degrees of elbow flexion (0.65 +/- 0.80 mm vs 0.97 +/- 0.35 mm, F: 4.49, post hoc: 0.048; p = .05). Proximal translation of the radius in midpronation was significantly greater than when the forearm was in a supinated position when the elbow was at 0 degrees or 90 degrees flexion (F: 14.90, post hoc: <0.01; p < .01, F: 19.11, post hoc: <0.01, p < .01). The arc of forearm rotation was significantly decreased at 0 degrees compared with 90 degrees of elbow flexion (129.3 degrees +/- 22.2 degrees vs 152.8 degrees +/- 14.4 degrees , F: 3.29, post hoc: 0.79; p = .09). The center of rotation shifted volarly and ulnarly with increasing elbow extension. CONCLUSIONS Elbow position affects the kinematics of the distal radioulnar joint. The kinematics of the distal radioulnar joint are primarily affected by forearm rotation and secondarily by elbow flexion. These findings have clinical relevance to our understanding of ulnar impaction, and how elbow position affects the proximal-distal translation of the radius. These findings have implications for the treatment of ulna impaction, radiographic evaluation of the distal ulna, and future biomechanical studies.
Journal of Bone and Joint Surgery, American Volume | 2011
J. Sebastiaan Souer; David Ring; Jesse B. Jupiter; Stefan Matschke; Laurent Audige; Marta Marent-Huber
BACKGROUND The impact of a single well-reduced or stable intra-articular fracture oriented in the sagittal plane on the outcome of internal fixation of a distal radial fracture is uncertain. We tested the hypothesis that wrist motion and function scores would not differ between patients with an extra-articular fracture and those with a single sagittal intra-articular fracture following open fracture reduction and internal fixation with use of a volar locking plate. METHODS Thirty-seven patients with a single sagittal intra-articular fracture of the distal aspect of the radius and seventy-four age and sex-matched patients with an extra-articular distal radial fracture were retrospectively analyzed with use of data gathered in a cohort study of plate and screw fixation of distal radial fractures. A volar locking plate was used in all patients. The two cohorts were analyzed for differences in motion, grip strength, pain, and Gartland and Werley, DASH (Disabilities of the Arm, Shoulder and Hand), and SF-36 (Short Form-36) scores six, twelve, and twenty-four months after surgery. Differences between the cohorts and differences within each cohort over time were determined with use of regression analysis and the likelihood ratio test. RESULTS Patients with a single sagittal intra-articular fracture and those an extra-articular fracture did not differ significantly with respect to motion, grip strength, Gartland and Werley score, or DASH score at any time point. However, there was a trend toward less pronation (95% compared with 98% of that in the contralateral arm) and less grip strength (76% compared with 81% of that in the contralateral arm) at six months and toward a smaller flexion-extension arc (118° compared with 128°) at one year after surgery in patients with a single sagittal intra-articular fracture. CONCLUSIONS Open reduction and volar locking plate and screw fixation of extra-articular fractures and of simple intra-articular fractures of the distal aspect of the radius are associated with comparable impairment and disability within two years of surgery.
Hand | 2010
Roderick van Leerdam; J. Sebastiaan Souer; Anneluuk L.C. Lindenhovius; David Ring
We tested the hypothesis that the original surgeon-investigator classification of a fracture of the distal radius in a prospective cohort study would have moderate agreement with the final classification by the team performing final analysis of the data. The initial post-injury radiographs of 621 patients with distal radius fractures from a multicenter international prospective cohort study were classified according to the Comprehensive Classification of Fractures, first by the treating surgeon-investigator and then by a research team analyzing the data. Correspondence between original and revised classification was evaluated using the Kappa statistic at the type, group and subgroup levels. The agreement between initial and revised classifications decreased from Type (moderate; Κtype = 0.60), to Group (moderate; Κgroup = 0.41), to Subgroup (fair; Κsubgroup = 0.33) classifications (all p < 0.05). There was only moderate agreement in the classification of fractures of the distal radius between surgeon-investigators and final evaluators in a prospective multicenter cohort study. Such variations might influence interpretation and comparability of the data. The lack of a reference standard for classification complicates efforts to lessen variability and improve consensus.
Hand | 2010
J. Sebastiaan Souer; James S. Davis; Marta Marent; David Ring
Five patients with a volar marginal articular fracture with dislocation (complete loss of apposition of the articular surfaces) were treated with open reduction and internal plate fixation. This is an unusual type of volar shearing fracture and represents the volar type of radiocarpal fracture–dislocation. The results of treatment were comparable to other volar shearing type fractures.
Journal of Hand Surgery (European Volume) | 2007
Lauren Adey; J. Sebastiaan Souer; Santiago A. Lozano-Calderon; William E. Palmer; Sang Gil Lee; David Ring
Journal of Hand Surgery (European Volume) | 2007
J. Sebastiaan Souer; Marijn Rutgers; Jonas Andermahr; Jesse B. Jupiter; David Ring