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Articles by A. A Allen
Total Records ( 3 ) for A. A Allen
  B. T Feeley , M. S Muller , A. A Allen , C. C Granchi and A. D. Pearle
  Background

The medial collateral ligament is a broad ligament that functions as the primary stabilizer against valgus knee stress, particularly at 30° of flexion.

Hypothesis

A double-bundle reconstruction technique that better restores the native medial collateral ligament anatomy will restore valgus and external rotation stability to a medial collateral ligament–deficient knee.

Study Design

Controlled laboratory study.

Methods

Seven fresh-frozen cadaveric knees were studied. A surgical navigation system was used to determine valgus opening and external rotation at 0° and 30° with a 9.8-N·m valgus stress applied to the tibia graft isometry at multiple points on the tibia and femur. Intact and disrupted medial collateral ligament knees were used as controls. Four repair techniques were tested: Bosworth, modified Bosworth, anatomical single bundle, and anatomical double bundle.

Results

Complete sectioning of the medial collateral ligament resulted in an increase in valgus opening of 5° at 0° and 7.7° at 30°. External rotation increased 4.6° at 0° and 9.7° at 30°. Single-bundle techniques (Bosworth, anatomical single bundle) did not restore valgus laxity at 0° or 30°; the anatomical single bundle did not restore external rotation at 0°. Double-bundle techniques (modified Bosworth, anatomical double bundle) restored valgus laxity and external rotation to the native knee conditions at 0° and 30°. At 30°, the modified Bosworth was 0.3° tighter and the anatomical double bundle 0.2° tighter than was the intact knee. The center of the medial collateral ligament origin on the femur to the proximal insertion of the superficial medial collateral ligament resulted in the most isometric graft position.

Conclusion

Medial collateral ligament reconstruction configurations that use a double-bundle reconstruction better resist valgus and external rotations in response to valgus stress than do single-bundle techniques.

Clinical Relevance

Although the medial collateral ligament often heals without surgical intervention, surgical reconstruction is occasionally necessary in grade III medial collateral ligament and combined ligamentous injuries to the knee. Double-bundle reconstruction of the medial collateral ligament better resists valgus forces across the knee and may allow for better surgical outcome after medial collateral ligament reconstruction.

  S. J Nho , R. S Adler , D. P Tomlinson , A. A Allen , F. A Cordasco , R. F Warren , D. W Altchek and J. D. MacGillivray
  Background

Recent studies have demonstrated predictable healing after arthroscopic rotator cuff repair at a single time point, but few studies have evaluated tendon healing over time.

Hypothesis

Rotator cuff tears that are intact on ultrasound at 1 time point will remain intact, and clinical results will improve regardless of healing status.

Study Design

Cohort study; Level of evidence, 3.

Methods

The Arthroscopic Rotator Cuff Registry was established to determine the effectiveness of arthroscopic rotator cuff repair with clinical outcomes using the American Shoulder and Elbow Surgeons score and ultrasound at 1 and 2 years, postoperatively. Patients were assigned to 1 of 3 groups based on ultrasound appearance: group 1, rotator cuff tendon intact at 1 and 2 years (n = 63); group 2, rotator cuff tendon defect at 1 and 2 years (n = 23); group 3, rotator cuff tendon defect at 1 year but no defect at 2 years (n = 7).

Results

The ultrasound appearance was consistent at 1 and 2 years for 86 of the 93 patients (92.5%). The patients in group 1 had a significantly lower mean age (57.8 ± 9.8 years) than the patients of group 2 (63.6 ± 8.6 years; P = .04). Group 2 had a significantly greater rotator cuff tear size (4.36 ± 1.6 cm) than group 1 (2.84 ± 1.1 cm; P = .00025). Each group had a significant improvement in American Shoulder and Elbow Surgeons scores from baseline to 2-year follow-up.

Conclusion

All intact rotator cuff tendons at 1 year remained intact at 2 years. A small group of patients with postoperative imaging did not appear healed by ultrasound at 1 year but did so at 2 years. Patients demonstrated improvement in American Shoulder and Elbow Surgeons shoulder scores, range of motion, and strength, regardless of tendon healing status on ultrasound.

  D. C Osbahr , S. S Swaminathan , A. A Allen , J. S Dines , S. H Coleman and D. W. Altchek
  Background

Ulnar collateral ligament reconstruction techniques have afforded baseball players up to a reported 90% return to prior or higher level of play. A subpopulation exists with less impressive clinical outcomes potentially related to the presence of a concomitant flexor-pronator mass injury.

Hypothesis/Purpose

Combined flexor-pronator and ulnar collateral ligament injuries occur in older players, and results in this group are inferior to those reported for isolated ulnar collateral ligament reconstructions.

Study Design

Case Series; Level of evidence, 4.

Methods

All baseball players who had ulnar collateral ligament reconstructions by 1 surgeon over a 6-year period were identified, and the authors studied those treated for a combined flexor-pronator and ulnar collateral ligament injury. The ulnar collateral ligament reconstruction was accomplished using the docking technique, and the flexor-pronator injury was treated with debridement if tendinotic or reattachment if torn. A 2-sample t test was conducted to evaluate the likelihood of developing the combined flexor-pronator/ulnar collateral ligament compared with ulnar collateral ligament injury based on age, while a Pearson 2 test was used to evaluate the likelihood of a patient being ≥30 years of age in the combined flexor-pronator/ulnar collateral ligament versus ulnar collateral ligament groups. Outcome was assessed using a modified Conway classification.

Results

A total of 187 male baseball players between 14 and 42 years of age (mean, 20.7 years) had an ulnar collateral ligament reconstruction by 1 surgeon. Eight (4%) of 187 baseball players were treated for the combined flexor-pronator/ulnar collateral ligament injury. There was a statistically significant difference in age between the ulnar collateral ligament group (20.1 years) and the flexor-pronator/ulnar collateral ligament group (33.4 years) (P < .001). Age ≥30 years was a statistically significant age limit to predict the presence of a combined flexor-pronator/ulnar collateral ligament injury (88%) compared with an isolated ulnar collateral ligament injury (1%) (P < .001). Outcomes were 1 excellent (12.5%), 2 fair (25%), and 5 poor (62.5%).

Conclusion

Combined fflexor-pronator and ulnar collateral ligament injuries in baseball players may portend a worse prognosis, with a 12.5% return to prior level of play. Older age (≥30 years) is a risk factor in the development of this combined injury. When combined flexor-pronator/ulnar collateral ligament injury is suspected preoperatively, patients should be counseled on expected outcomes appropriately.

 
 
 
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