Background:. Primary traumatic anterior shoulder dislocations can be associated with displaced anterior glenoid rim fractures. Nonoperative treatment of such fractures has been shown to have ...excellent results in a small cohort of patients; as such, we have been treating these fractures nonoperatively, regardless of fragment size and degree of displacement, provided that post-reduction computed tomography scans revealed an anteroposteriorly centered humeral head. The aim of this study was to analyze the medium- to long-term results of nonoperative treatment of displaced anterior glenoid rim fractures, assessing in particular the residual instability and development of osteoarthritis. Methods:. In a 2-center study, 30 patients with a mean age of 48 years (range, 29 to 67 years) were evaluated clinically with use of the Subjective Shoulder Value, Constant score, American Shoulder and Elbow Surgeons score, and Western Ontario Shoulder Instability index, as well as radiographically with use of radiographs and computed tomography scans at a mean follow-up of 9 years (range, 5 to 14 years). Results:. Fracture-healing was documented in all patients. Seven patients (23%) had post-fracture onset of osteoarthritis (5 with Samilson grade I and 2 with Samilson grade IV). Of these, 1 patient had recurrent instability that was successfully treated with hemiarthroplasty 9 years after the index injury (relative Constant score, 101%), and was excluded from further analysis. No other patient had a recurrent redislocation, subluxation, or positive apprehension. The other 6 patients with new-onset radiographic osteoarthritis were pain-free (mean Constant score pain scale, 15 points) with good shoulder function (relative Constant score, 84% to 108%). A total of 26 patients (90%) rated their functional outcome as good or very good, and 3 patients (10%) rated it as fair. The mean relative Constant score was 97% (range, 61% to 108%), the mean American Shoulder and Elbow Surgeons score was 92 points (range, 56 to 100 points), and the mean Western Ontario Shoulder Instability index score was 126 points (range, 0 to 660 points). All patients returned to full-time work. Conclusions:. Nonoperative treatment of anterior glenoid rim fractures following primary traumatic anterior shoulder dislocation results in excellent clinical outcomes with a very low rate of residual instability and, thus, treatment failure. Asymptomatic radiographic osteoarthritis occurred in roughly 1 of 4 patients. Level of Evidence:. Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.
The clinical outcome for patients with documented rerupture after open repair of one or more rotator cuff tendons is not well known. The purpose of this study was to evaluate the clinical outcomes of ...a consecutive series of rotator cuff reruptures after repair and to provide information concerning the advisability of rotator cuff repair in situations in which there may be a high probability of rerupture.
During prospective follow-up after rotator cuff repairs, we detected, with magnetic resonance imaging, structural failure of the repair in twenty patients, who had a mean age of fifty-nine years at the time of the rotator cuff repair. All patients were clinically examined for the purpose of this report at a mean of thirty-eight months.
The reruptures invariably involved the originally torn tendon but were smaller than the original tear in sixteen of the twenty patients. Fatty degeneration of the supraspinatus and infraspinatus muscles, atrophy of the supraspinatus muscle, and glenohumeral osteoarthritis progressed significantly from the preoperative state (p < 0.05). At the time of the most recent follow-up, the subjective shoulder value averaged 75 percent of the value for a normal shoulder. Eleven patients were very satisfied with the result, six were satisfied, two were disappointed, and one was dissatisfied. The mean relative score according to the system of Constant and Murley had increased from 49 percent of the score for a normal shoulder preoperatively to 83 percent postoperatively (p = 0.0001). Pain had decreased significantly, and the ranges of active, pain-free forward elevation and abduction as well as the abduction strength had improved significantly (p < 0.05). The clinical outcome was significantly correlated with the size of the postoperative tear, the stage of postoperative fatty muscle degeneration of the infraspinatus and subscapularis, the postoperative acromiohumeral distance, and the degree of postoperative glenohumeral osteoarthritis (p < 0.05).
This study documents that an attempt at rotator cuff repair significantly decreases pain (p = 0.0026) and significantly improves function (p = 0.0005) and strength (p = 0.0137) even if magnetic resonance imaging documents that the repair has failed. This finding suggests that the potential for rerupture should not be considered a formal contraindication to an attempt at repair if optimal functional recovery is the goal of treatment.
Forty-one patients scheduled for shoulder surgery underwent computed tomography (CT) and magnetic resonance imaging (MRI) examination of their affected shoulder to verify whether fatty degeneration ...of the rotator cuff muscles could reproducibly be assessed by CT or by MRI and whether the grading with the 2 methods was comparable. In addition, rotator cuff muscle cross-sectional areas were measured on parasagittal MRI scans to establish a possible correlation between rotator cuff muscle atrophy and fatty degeneration. Interobserver reproducibility for grading fatty degeneration was good to excellent for CT and for MRI. The correlation between MRI and CT was fair to moderate and remained unsatisfactory, even if the classification system was simplified with only a 3- rather than a 5-grade scale as originally proposed. The degree of fatty degeneration was significantly related to the amount of atrophy of the respective muscles.
Collagen cross-links are fundamental to the mechanical integrity of tendon, with orderly and progressive enzymatic cross-linking being central to healthy development and injury repair. However, the ...nonenzymatic cross-links that form as we age are associated with increased tendon brittleness, diminished mechanical resistance to injury, and impaired matrix remodeling. Collagen cross-linking thus sits at the center of tendon structure and function, with important implications to age, disease, injury, and therapy. The current review touches on these aspects from the perspective of their potential relevance to the shoulder surgeon. We first introduce the most well-characterized endogenous collagen cross-linkers that enable fibrillogenesis in development and healing. We also discuss the glycation-mediated cross-links that are implicated in age- and diabetes-related tendon frailty and summarize work toward therapies against these disadvantageous cross-links. Conversely, we discuss the introduction of exogenous collagen cross-links to augment the mechanical properties of collagen-based implants or native tendon tissue. We conclude with a summary of our early results using exogenous collagen cross-linkers to prevent tendon tear enlargement and eventual failure in an in vitro model of partial tendon tear.
The complications of reversed total shoulder arthroplasty (RTSA) requiring an additional intervention, their treatment options and outcome are poorly known. It was therefore the purpose of this ...retrospective study, to identify the reasons for revision of RTSA and to report outcomes.
Four hundred and forty-one performed RTSA implanted between 1999 and 2008 were screened. Sixty-seven of these cases had an additional intervention to treat a complication. Causes were identified in these 67 cases and the outcome of the first 37 patients who could be followed for more than two years after their first additional intervention was analyzed.
Of 441 RTSA, 67 cases (15%) needed at least one additional intervention to treat a complication, 30 of them needed a second, eleven a third and four a fourth additional intervention. The most common complication requiring a first intervention was instability (18%) followed by hematoma or superficial wound complications (15%) and complications of the glenoid component (12%). Patients benefitted from RTSA despite the need of additional interventions as indicated by a mean increase in total Constant-Murley score from 23 points before RTSA to 46 points at final follow-up (p < 0.0001).
Instability, hematoma or superficial wound complications and complications of the glenoid component are the most common reasons for an additional intervention after RTSA. Patients undergoing an additional intervention as treatment of these complications profit significantly as long as the prosthesis remains in place.
Purpose
Primary glenohumeral osteoarthritis is commonly associated with static posterior subluxation of the humeral head. Scapulae with static/dynamic posterior instability feature a superiorly and ...horizontally oriented acromion. We investigated whether the acromion acts as a restraint to posterior humeral translation.
Methods
Five three-dimensional (3D) printed scapula models were biomechanically tested. A statistical shape mean model (SSMM) of the normal scapula of 40 asymptomatic shoulders was fabricated. Next, a SSMM of scapular anatomy associated with posterior subluxation was generated using data of 20 scapulae (“B1”). This model was then used to generate three models of surgical correction: glenoid version, acromial orientation, and acromial
and
glenoid orientation. With the joint axially loaded (100N) and the humerus stabilized, an anterior translation force was applied to the scapula in 35°, 60° and 75° of glenohumeral flexion. Translation (mm) was measured.
Results
In the normal scapula, the humerus translates significantly less to contact with the acromion compared to all other configurations (
p
< .000 for all comparisons; i.e. 35°: “normal” 8,1 mm (± 0,0) versus “B1” 11,9 mm (± 0,0) versus “B1 Acromion Correction” 12,2 mm (± 0,2) versus “B1 Glenoid Correction” 13,3 mm (± 0,1)). Restoration of normal translation was only achieved with correction of glenoid
and
acromial anatomy (i.e. 75°: “normal” 11 mm (± 0,8) versus “B1 Acromion Correction” 17,5 mm (± 0,1) versus “B1 Glenoid Correction” 19,7 mm (± 1,3) versus “B1 Glenoid + Acromion Correction” 11,5 mm (± 1,1)).
Conclusions
Persistence or recurrence of static/dynamic posterior instability after correction of glenoid version alone may be related to incomplete restoration of the intrinsic stability that is conferred by a normal acromial anatomy.
Level of Evidence V
biomechanical study
Background The surgical treatment of malunions after midshaft clavicle fractures is associated with a number of potential complications and the surgical procedure is challenging. However, with ...appropriate and meticulous preoperative surgical planning, the surgical correction yields satisfactory results. The purpose of this study was to provide a guideline and detailed overview for the computer-assisted planning and 3-dimensional (3D) correction of malunions of the clavicle. Methods The 3D bone surface models of the pathologic and contralateral sides were created on the basis of computed tomography data. The computer-assisted assessment of the deformity, the preoperative plan, and the design of patient-specific guides enabling compression plating are described. Results We demonstrate the benefit and versatility of computer-assisted planning for corrective osteotomies of malunions of the midshaft clavicle. In combination with patient-specific guides and compression plating technique, the correction can be performed in a more standardized fashion. We describe the determination of the contact-optimized osteotomy plane. An osteotomy along this plane facilitates the correction and enlarges the contact between the fragments at once. We further developed a technique of a stepped osteotomy that is based on the calculation of the contact-optimized osteotomy plane. The stepped osteotomy enables the length to be restored without the need of structural bone graft. The application of the stepped osteotomy is presented for malunions of the clavicle with shortening and excessive callus formation. Conclusions The 3D preoperative planning and patient-specific guides for corrective osteotomies of the clavicle may help reduce the number of potential complications and yield results that are more predictable.
Background It was the purpose of this paper to analyze structural, functional, and electrophysiologic variables that may determine preserved overhead function for patients with massive rotator cuff ...tears. Methods Nineteen patients (20 shoulders) were prospectively included in either the pseudoparalytic (n = 9) or the non-pseudoparalytic group (n = 11). Fatty infiltration was graded according to Goutallier, and anterior (subscapularis) and posterior (infraspinatus and teres minor) tear extension was graded 0 (no involvement) to 4 (full tear) on magnetic resonance imaging. Glenohumeral and scapulothoracic rhythm was assessed by fluoroscopic motion analysis, and electromyographic evaluation of the deltoid muscle was performed. Results We found no significant difference of fatty infiltration of the supraspinatus (3.9 vs 3.6), infraspinatus (3.9 vs 3.8), and teres minor (1.7 vs 0.6) or of the posterior tear extension (2.6 vs 2.0) between pseudoparalytic and non-pseudoparalytic shoulders. Global tear extension in the parasagittal plane (205° vs 163°) and subscapularis involvement (2.6 vs 1.2), however, showed significant differences between the two groups, and no patient with a full-thickness supraspinatus and infraspinatus tear with extension into the inferior half of the subscapularis was able to lift the arm to 90°. Fluoroscopic assessment revealed almost total loss of active glenohumeral abduction in the pseudoparalytic group. Conclusion Despite global tear extension, the single most important predictor for preserved shoulder function is the integrity of the inferior subscapularis insertion. Furthermore, electromyographic evaluation identifies a well-differentiated deltoid innervation as beneficial for a well-preserved shoulder function, but it does not protect from pseudoparalysis.
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