Trevor R. Gaskill

Treatment of clavicle fractures: current concepts review

Clavicle fractures are common in adults and children. Most commonly, these fractures occur within the middle third of the clavicle and exhibit some degree of displacement. Whereas many midshaft clavicle fractures can be treated nonsurgically, recent evidence suggests that more severe fracture types exhibit higher rates of symptomatic nonunion or malunion. Although the indications for surgical fixation of midshaft clavicle fractures remain controversial, they appear to be broadening. Most fractures of the medial or lateral end of the clavicle can be treated nonsurgically if fracture fragments remain stable. Surgical intervention may be required in cases of neurovascular compromise or significant fracture displacement. In children and adolescents, these injuries mostly consist of physeal separations, which have a large healing potential and can therefore be managed conservatively. Current concepts of clavicle fracture management are discussed including surgical indications, techniques, and results.

The Rotator Interval: Pathology and Management

The rotator interval describes the anatomic space bounded by the subscapularis, supraspinatus, and coracoid. This space contains the coracohumeral and superior glenohumeral ligament, the biceps tendon, and anterior joint capsule. Although a definitive role of the rotator interval structures has not been established, it is apparent that they contribute to shoulder dysfunction. Contracture or scarring of rotator interval structures can manifest as adhesive capsulitis. It is typically managed nonsurgically with local injections and gentle shoulder therapy. Recalcitrant cases have been successfully managed with an arthroscopic interval release and manipulation. Conversely, laxity of rotator interval structures may contribute to glenohumeral instability. In some cases this can be managed with one of a number of arthroscopic interval closure techniques. Instability of the biceps tendon is often a direct result of damage to the rotator interval. Damage to the biceps pulley structures can lead to biceps tendon subluxation or dislocation depending on the structures injured. Although some authors describe reconstruction of this tissue sling, most recommend tenodesis or tenotomy if it is significantly damaged. Impingement between the coracoid and lesser humeral tuberosity is a relatively well-established, yet less common cause of anterior shoulder pain. It may also contribute to injury of the anterosuperior rotator cuff and rotator interval structures. Although radiographic indices are described, it appears intraoperative dynamic testing may be more helpful in substantiating the diagnosis. A high index of suspicion should be used in association with biceps pulley damage or anterosuperior rotator cuff tears. Coracoid impingement can be treated with either open or arthroscopic techniques. We review the anatomy and function of the rotator interval. The presentation, physical examination, imaging characteristics, and management strategies are discussed for various diagnoses attributable to the rotator interval. Our preferred methods for treatment of each lesion are also discussed.

Biomechanical Analysis of Two Tendon Posterosuperior Rotator Cuff Tear Repairs: Extended Linked Repairs and Augmented Repairs

PURPOSE The purpose of this study was to compare single-row (SR), extended double-row (DR), and augmented, extended double-row (aDR) rotator cuff repairs in a two-tendon, posterosuperior rotator cuff tear (RCT) model with intact rotator cuff tendons. METHODS RCTs were created and randomly assigned to SR, DR, or aDR repair (5 each) in 20 cadaveric shoulder specimens. A collagen scaffold was used for augmentation. In the remaining 5 specimens, the rotator cuffs were left intact. All specimens were cyclically loaded from 25 to 75 N for 50 cycles. Every 50 cycles, peak load was increased by 25 N until failure occurred. Cyclic stiffness and number of cycles were analyzed. RESULTS The SR (72.9 ± 4.64 N/mm)- and aDR (72.6 ± 11.8 N/mm)-repaired specimens differed significantly in stiffness from the intact specimens (93.1 ± 14.8 N/mm) at ≥100 N (P < .05). The intact specimens and DR- and aDR-repaired specimens endured more cycles to failure (1,556 ± 677, 1,302 ± 248, and 1,211 ± 95, respectively) than the SR-repair specimens (388 ± 72 cycles, 260 ± 4 N) (P < .05 for all groups). CONCLUSIONS Linked DR constructs were significantly stronger than SR repairs in this two-tendon RCT model and approached the strength of the intact rotator cuff. Augmentation with a collagen patch (aDR) did not influence biomechanical repair qualities in this model, but did result in less variability in failure load and more consistency in the mode of failure. CLINICAL RELEVANCE The biomechanical properties of extended linked DR constructs are superior to those of SR constructs for repair of two-tendon RCTs, and are not compromised by graft augmentation.

Management of multidirectional instability of the shoulder.

&NA; Multidirectional shoulder instability is defined as symptomatic instability in two or more directions. Instability occurs when static and dynamic shoulder stabilizers become incompetent due to congenital or acquired means. Nonspecific activity‐related pain and decreased athletic performance are common presenting complaints. Clinical suspicion for instability is essential for timely diagnosis. Several examination techniques can be used to identify increased glenohumeral translation. It is critical to distinguish increased laxity from instability. Initial management begins with therapeutic rehabilitation. If surgical management is required, capsular plication has been used successfully. Advanced arthroscopic techniques offer several advantages over traditional open approaches and may have similar outcomes. The role of rotator interval capsular plication is controversial, but it may be used to augment capsular plication in patients with specific patterns of instability. Despite encouraging results, outcomes remain inferior to those associated with traumatic unidirectional instability.

Arthroscopic Management of Glenohumeral Arthrosis: Humeral Osteoplasty, Capsular Release, and Arthroscopic Axillary Nerve Release as a Joint-Preserving Approach

Glenohumeral arthrosis frequently results in substantial discomfort and activity limitations. Shoulder arthroplasty has been shown to provide reliable pain relief under these circumstances in older, less active populations. Younger patients, however, who desire to continue participation in high-demand activities, may not be optimal candidates for glenohumeral arthroplasty. Arthroscopic debridement has been reported to provide incomplete symptomatic relief in this cohort of patients. It is evident from cadaveric studies that the axillary nerve runs in close proximity to the inferior glenohumeral capsule. An inferior humeral osteophyte of sufficient size may compress the axillary nerve and potentially contribute to posterior shoulder pain in a manner similar to quadrilateral space syndrome. Therefore we present a technique for and early results of the arthroscopic management of glenohumeral arthrosis in young, high-demand patients. This technique combines traditional glenohumeral debridement and capsular release with inferior humeral osteoplasty and arthroscopic transcapsular axillary nerve decompression. In the appropriate patient, these additions may provide symptomatic relief that is greater than that with simple debridement alone.

Acromioclavicular joint separations

Acromioclavicular (AC) joint separations are common injuries of the shoulder girdle, especially in the young and active population. Typically the mechanism of this injury is a direct force against the lateral aspect of the adducted shoulder, the magnitude of which affects injury severity. While low-grade injuries are frequently managed successfully using non-surgical measures, high-grade injuries frequently warrant surgical intervention to minimize pain and maximize shoulder function. Factors such as duration of injury and activity level should also be taken into account in an effort to individualize each patient’s treatment. A number of surgical techniques have been introduced to manage symptomatic, high-grade injuries. The purpose of this article is to review the important anatomy, biomechanical background, and clinical management of this entity.

The Effect of Pelvic Tilt on Radiographic Markers of Acetabular Coverage

Background: Radiographic indices of acetabular coverage are crucial to objectively characterize femoroacetabular impingement and plan bony decompression. It is established that changes in pelvic inclination result in alterations of acetabular crossover; however, it is unclear what influence this has on other measures of acetabular anatomy. Hypothesis: The objective of the present study was to determine if, and to what degree, a variation in pelvic tilt alters 4 measures of acetabular anatomy: the angle of Sharp, Tönnis angle, percentage of acetabular crossover, and lateral center edge angle (LCEA). The hypothesis was that pelvic tilt would significantly alter all measures of acetabular coverage. Study Design: Descriptive laboratory study. Methods: Fluoroscopic images of 8 adult hemipelvises were obtained at 7 positions of rotation in the sagittal plane to investigate the change of each measurement in response to pelvic orientation. Two reviewers obtained measurements from each image at 2 separate time points. Results: Each increment of pelvic inclination resulted in increased measures of acetabular coverage for all measurements, whereas each increment of decreased pelvic inclination resulted in decreased measures of acetabular coverage for all measurements. Significant differences in the measured LCEA, acetabular crossover, and Tönnis angle were identified at each increment of tilt as compared with neutral radiographs. No significant differences could be identified for the angle of Sharp. Conclusion: Pelvic tilt significantly alters the measures of LCEA, crossover, and Tönnis angle in this cadaveric study. Pelvic inclination results in increased measures of acetabular coverage, whereas decreasing inclination decreases each measure. Clinical Relevance: Given the known individual and positional pelvic tilt variability, standing anteroposterior pelvic radiographs may provide a more physiological representation of acetabular coverage in the young adult population.

Snapping scapula syndrome: diagnosis and management.

Scapulothoracic bursitis and snapping scapula syndrome are rare diagnoses that contribute to considerable morbidity in some patients. These conditions represent a spectrum of disorders characterized by pain with or without mechanical crepitus. They are commonly identified in young, active patients who perform repetitive overhead activities. Causes include anatomic scapular or thoracic variations, muscle abnormalities, and bony or soft‐tissue masses. Three‐dimensional CT and MRI aid in detecting these abnormalities. Nonsurgical therapy is the initial treatment of choice but is less successful than surgical management in patients with anatomic abnormalities. In many cases, scapular stabilization, postural exercises, or injections eliminate symptoms. When nonsurgical treatment fails, open and endoscopic techniques have been used with satisfactory results. Familiarity with the neuroanatomic structures surrounding the scapula is critical to avoid iatrogenic complications. Although reported outcomes of both open and endoscopic scapulothoracic decompression are encouraging, satisfactory outcomes have not been universally achieved.

Management of clavicle nonunion and malunion

BACKGROUND Clavicle fractures are common injuries of the shoulder girdle and occasionally result in nonunion or symptomatic malunion. When present, these chronic injuries can result in considerable shoulder dysfunction. A number of surgical techniques have been described for the management of these injuries. Current literature suggests that supplemental bone grafting may not be necessary in all cases but should be considered in the setting of atrophic nonunion. However, optimal treatment is controversial, as discussed in the literature. This article highlights the current treatment options based on the existing literature and describes our preferred techniques. METHODS We carried out a comprehensive review of the PubMed and Medline databases using multiple keywords (eg, clavicle fracture, clavicle nonunion, and clavicle malunion) to identify the relevant literature regarding this topic. Reference lists of the relevant articles were reviewed for additional important articles. CONCLUSION Nonunion and malunion of the clavicle remain challenging problems. Reliable bony union and improved shoulder function can be expected with thoughtful surgical planning, appropriate implant choice, and meticulous surgical technique.

Variability of Acetabular Coverage Between Supine and Weightbearing Pelvic Radiographs

Background: Radiographic measures of acetabular coverage are essential screening tools used to characterize bony structure contributing to femoroacetabular impingement (FAI). Small changes in pelvic tilt result in altered radiographic measures of acetabular coverage. Positional changes in pelvic tilt are known to occur between the supine and weightbearing positions. It is unclear whether alteration of pelvic tilt between these positions is clinically sufficient to influence measures of acetabular coverage. Purpose/Hypothesis: To determine whether, and to what degree, imaging position (supine vs weightbearing) is capable of altering several measures of acetabular orientation: pubic symphysis to sacrococcygeal distance (PSSC), angle of Sharp (SA), Tönnis angle (TA), percentage of acetabular crossover (CO), and lateral center-edge angle of Wiberg (LCEA). The hypothesis was that imaging position would significantly alter all measures of acetabular orientation. Study Design: Cohort study (diagnosis); Level of evidence, 2. Methods: A total of 50 consecutive symptomatic hips referred to a single provider for FAI were evaluated with standardized supine and weightbearing anteroposterior pelvic radiographs. Two independent reviewers blinded to patient positioning reviewed each radiograph at 2 separate time points. Mean measurements in each position were compared by use of paired Student t tests, and a Bonferroni-adjusted significance level of P = .01 was used to represent significance. Results: Statistically significant differences between the supine and weightbearing radiographs were identified for PSSC and all measures of acetabular coverage (P < .003). The mean PSSC decreased between the supine and weightbearing positions by an average of 13.4 mm (P < .001), thereby resulting in decreased mean LCEA, TA, SA, and CO of 1.2°, 1.3°, 0.8°, and 6.3%, respectively (P < .002). The change in positional pelvic tilt was not uniformly predictable and accounted for large measurement changes in some individuals. PSSC also demonstrated considerable inter- and intrasubject variability but averaged 55.8 mm supine and 44.9 mm weightbearing for females and 37.0 mm supine and 20.6 mm weightbearing for males. Conclusion: In this study of nonarthritic adult patients with hip pain, the data indicate that positional changes are capable of significantly altering pelvic tilt and radiographic measures of acetabular coverage. It appears that the weightbearing position typically, but not universally, correlates with additional posterior pelvic tilt and decreased measures of acetabular coverage. Individual positional variability can contribute to large-magnitude changes in radiographic acetabular measures.