bluuebunny/crossref_metadata_2025 huggingface dataset:
The Ultrastructure of Macrophages in Granulomatous Colitis of Boxer Dogs
Authors: Van Kruiningen H. J.
Published: July 2017

Thirteen cases of granulomatous colitis of Boxer dogs were studied by electron microscopy to define the contents of macrophages and to seek infectious agents. Macrophages were of three types. The most numerous were distended with residual bodies composed of membranes and parallel pairs of membranes, many arranged in circular patterns. A second common form had heterogeneous cytoplasm distended with phagosomes containing numerous small granular spheres of various sizes and electron densities. The least common were ‘young’ macrophages containing phagocytic vacuoles. Rare macrophages in four of 13 dogs contained bacteria. Macrophages in five of the dogs contained abundant coccoid, coccobacillary or lobulated granular structures, 100–500 nm in diameter, resembling chlamydia. Transition from phagocytic particle to phagosome to residual body was apparent. Granulomatous colitis of Boxer dogs is probably caused by a lipid-rich, ribosome-rich, coccoid to coccobacillary organism that possesses a cell membrane and sometimes a nucleoid, and ranges from 100 to 500 nm in size.
Renal Pathology in Captive Baboons (Papio cynocephalus)
Authors: Brack M.
Published: July 2017

Baboons, unlike many other species of nonhuman primates, rarely have spontaneous renal diseases of clinical or morphologic significance. The most common renal lesions in captive baboons were minor interstitial lymphoreticular infiltrates and hyalinization of occasional glomeruli. Embolic pyelonephritis associated with septicemia contributed to the deaths of several young baboons. One adult male had acute myoglobinuric nephrosis (Meyer-Betz disease) with extensive skeletal muscle necrosis.
Quantification of Anterior Translation of the Humeral Head in the Throwing Shoulder
Authors: Ellenbecker Todd S. , Mattalino Angelo J. , Elam Eric , Caplinger Roger
Published: July 2017

Clinical evaluation of humeral head translation relies mainly on manual tests to measure laxity in the human shoulder. The purposes of this study were to determine whether side-to-side differences exist in anterior humeral head translation in professional baseball pitchers, to compare manual laxity testing with stress radiography for quantifying humeral head translation, and to test intrarater reliability of the manual humeral head translation and stress radiography tests. Twenty professional baseball pitchers underwent bilateral manual anterior humeral head translation and stress radiographic tests. Stress radiography was performed by imparting a 15-daN anterior load to the shoulder in 90° of abduction with both neutral and 60° of external rotation and recording the glenohumeral joint translation at rest and under stress in each position. Eight subjects were retested to assess the reliability of these methods. Results showed no significant difference between the dominant and nondominant extremity in the amount of anterior humeral head translation measured manually and with stress radiography, nor significant correlation between anterior humeral head translation measured manually and by stress radiography. Testretest reliability was moderate-to-poor for the manual humeral head translation test and moderate for stress radiography.
Electromyographic and Kinematic Analysis of Cutting Maneuvers
Authors: Colby Scott , Francisco Anthony , Bing Yu , Kirkendall Donald , Finch Michael , Garrett William
Published: July 2017

The objective of this study was to qualitatively characterize quadriceps and hamstring muscle activation as well as to determine knee flexion angle during the eccentric motion of sidestep cutting, cross-cutting, stopping, and landing. Fifteen healthy collegiate and recreational athletes performed the four movements while knee angle and electromyographic activity (surface electrodes) of the vastus lateralis, vastus medialis obliquus, rectus femoris, biceps femoris, and medial hamstring (semimembranosus/semitendinosus) muscles were recorded. The results indicated that there is high-level quadriceps muscle activation beginning just before foot strike and peaking in mid-eccentric motion. In these maneuvers, the level of quadriceps muscle activation exceeded that seen in a maximum isometric contraction. Hamstring muscle activation was sub-maximal at and after foot strike. The maximum quadriceps muscle activation for all maneuvers was 161% maximum voluntary contraction, while minimum hamstring muscle activity was 14%. Foot strike occurred at an average of 22° of knee flexion for all maneuvers. This low level of hamstring muscle activity and low angle of knee flexion at foot strike and during eccentric contraction, coupled with forces generated by the quadriceps muscles at the knee, could produce significant anterior displacement of the tibia, which may play a role in anterior cruciate ligament injury.
The Effect of Knee Flexion Angle and Application of an Anterior Tibial Load at the Time of Graft Fixation on the Biomechanics of a Posterior Cruciate Ligament-Reconstructed Knee
Authors: Harner Christopher D. , Janaushek Marsie A. , Ma C. Benjamin , Kanamori Akihiro , Vogrin Tracy M. , Woo Savio L-Y.
Published: July 2017

Ten knees were studied using a robotic testing system under a 134-N posterior tibial load at five flexion angles. Three knee positions were used to study the effect of flexion angle at the time of graft fixation (full extension, 60°, and 90°) and two were used to study the effect of anterior tibial load (60° and 90°). Knee kinematics and in situ forces were determined for the intact ligament and the graft for each reconstruction. Graft fixation at full extension significantly decreased posterior tibial translation compared with the intact knee by up to 2.9 2.9 mm at 30°, while in situ forces in the graft were up to 18 35 N greater than for the intact ligament. Conversely, posterior tibial translation for graft fixation at 90° was significantly greater than that of the intact knee by up to 2.2 1.1 mm at all flexion angles; in situ forces decreased as much as 33 30 N. When an anterior tibial load was applied before graft fixation at 90° of flexion, posterior tibial translation did not differ from the intact knee from 30° to 120°, while the in situ force in the graft did not differ from the intact ligament at full extension, 60°, and 120° of flexion. These data suggest that graft fixation at full extension may overconstrain the knee and elevate in situ graft forces. Conversely, fixation with the knee in flexion and an anterior tibial load best restored intact knee biomechanics.
Characteristics of Patients with Primary Acute Lateral Patellar Dislocation and Their Recovery within the First 6 Months of Injury
Authors: Atkin Dave M. , Fithian Donald C. , Marangi Kent S. , Stone Mary Lou , Dobson Barbara E. , Mendelsohn Cerrah
Published: July 2017

We prospectively studied the characteristics and early recovery of an unselected population of patients who had acute first-time lateral patellar dislocation. The recovery program used standardized rehabilitation, emphasizing range of motion, muscle strength, and return of function. Patients returned to stressful activities including sports as tolerated when they regained full passive range of motion, had no effusion, and when quadriceps muscle strength was at least 80% compared with the noninjured limb. Seventy-four patients met the enrollment criteria; 37 men and 37 women. The average age was 19.9 years, and preinjury sports participation was similar to that of ligament-injury patients. Four percent of patients (N 3) had a history of birth complications, 3% (N 2) had a history of lower extremity problems as an infant or child, and 9% (N 7) had a family history of patellar dislocation. Radiographs revealed a 50% incidence (N 37) of patella alta; all patients demonstrated lateral patellar overhang. Patients regained range of motion (mean, 0° to 132°) by 6 weeks. Sports participation remained significantly reduced throughout the first 6 months after injury, with the greatest limitations in kneeling and squatting. At 6 months, 58% of patients (N 43) noted limitation in strenuous activities. The patients who had acute primary patellar dislocation were young and active. Most injuries occurred during sports, and few patients had abnormal physical features, contradicting any stereotype of an overweight, sedentary, adolescent girl whose patella dislocates with little or no trauma.
The Benefit of a Single-Leg Strength Training Program for the Muscles around the Untrained Ankle: A Prospective, Randomized, Controlled Study
Authors: Uh Benjamin S. , Beynnon Bruce D. , Helie Bryce V. , Alosa Denise M. , Renstrom A.
Published: July 2017

Severe ankle injuries can require extended periods of immobilization that adversely affect the strength of the ankle muscles. We have investigated a single-leg strength training program of the muscles surrounding the ankle to determine if it produces a crossover benefit for the contralateral ankle muscles. Twenty subjects without any history of ankle injuries were randomly divided into a control and a training group. Both groups underwent isokinetic testing of the ankle muscles at the beginning and end of an 8-week period. The control group maintained normal activities between the tests. Half of the training group trained the dominant leg only and the other half trained the nondominant leg only for the 8-week period, three times per week. The subjects who trained the dominant leg improved peak torque values by 8.5% in the trained leg and 1.5% in the untrained leg. Similarly, the subjects who trained the nondominant leg improved peak torque values by 9.3% in the trained leg and 3.5% in the untrained leg. In contrast, the control group showed no significant change in peak torque, power, or endurance between the initial and final tests. With improvements in peak torque as high as 40% in the trained leg and a crossover benefit of 19% in the untrained leg in eccentric inversion, this strength training technique deserves further investigation in an injured population where the benefits may be more substantial.
Clinical Comparison of Intraarticular Anterior Cruciate Ligament Reconstruction Using Autogenous Semitendinosus and Gracilis Tendons in Men versus Women
Authors: Noojin Frank K. , Barrett Gene R. , Hartzog Charles W. , Nash Carrie R.
Published: July 2017

Reconstruction of the anterior cruciate ligament using a hamstring tendon autograft has often been recommended for female athletes. We compared the results of acute, isolated, intraarticular anterior cruciate ligament reconstructions using quadruple-looped hamstring autografts in 39 female and 26 male patients. All reconstructions were performed by the same surgeon using a similar surgical technique and the same postoperative management. In each case, patients had Endobutton femoral fixation and either post or button fixation for the tibial side. The average follow-up was 40.9 months for women and 39.0 months for men. Objective analysis of results included examination for the presence of effusion and crepitus, Lachman and pivot shift testing, and KT-1000 arthrometer testing for side-to-side differences. Subjective analysis consisted of a 15-item visual analog scale completed by patients postoperatively, and pre- and postoperative Tegner and Lysholm scores. The clinical failure rate was 23% (9 of 39) for the female patients and 4% (1 of 26) for the male patients, which was statistically significant. There was also a trend toward increased laxity in female patients. Subjectively, the women also reported a higher frequency and intensity of pain. Based on Tegner activity levels, more of the men returned to their preinjury level of activity than did the women. When compared with the male patients, female patients had a significantly higher failure rate after reconstruction.
In Vitro Structural Properties of Braided Tendon Grafts
Authors: Nicklin Sean , Waller Craig , Walker Peter , Chung Wui K. , Walsh William R.
Published: July 2017

In an effort to increase strength in hamstring tendon grafts for anterior cruciate ligament reconstruction, braiding or weaving of the tendons has been suggested. The purpose of this study was to examine the biomechanical properties of two braiding techniques compared with a four-stranded tendon graft using a sheep model. Digital extensor tendons from 5 adult sheep were harvested in 28 matched pairs and randomly allocated to French plait or four-stranded weave. The grafts were tested in a hydraulic testing machine with the tendons secured in brass grips frozen with liquid carbon dioxide. The tendons were preconditioned to a distraction of 1 mm for 10 cycles followed by testing to failure at 50 mm/sec, with a data acquisition rate of 1000 Hz. The stiffness, ultimate load to failure, and the mode of failure were recorded. All braided samples failed at the midsubstance, while the four-stranded controls failed at the grip interface. There was a significant reduction in strength and stiffness of the braided samples compared with the controls. This study demonstrated that braiding decreases the strength and stiffness of a four-stranded tendon graft by up to 54% and 85%, respectively. This finding is supported by the work of Hearle et al. (1969), who demonstrated that the decrease in strength of fiber bundles is equal to the square of the cosine of the twist angle. The twist angle in our samples was approximately 45°, which equates to a decrease in strength of 50%.
Recurrent Shoulder Instability after Open Reconstruction in Athletes Involved in Collision and Contact Sports
Authors: Uhorchak John M. , Arciero Robert A. , Huggard Donald , Taylor Dean C.
Published: July 2017

The purpose of this study was to evaluate the incidence of recurrent instability in a group of young athletes who underwent open shoulder stabilization with a modified Bankart repair and anterior capsulorrhaphy. Recurrent dislocation was defined as an instability episode resulting in complete dislocation requiring manual reduction. Recurrent subluxation was defined as the subjective history of the shoulder “slipping or popping out” or pain and apprehension that caused cessation of athletics for at least 1 day. Sixty-six patients (64 men and 2 women) were included in the study. A collision sport precipitated instability in 53 patients and a contact sport in 13. The average follow-up was 47 months (range, 24 to 72). The average American Shoulder and Elbow Surgeons score was 95 points (range, 71 to 100). The average Rowe score was 80 points (range, 40 to 100). Two patients had experienced recurrent dislocation after surgery (3%). Eight patients (12%) had rare (fewer than three) episodes of postsurgical subluxation. Five patients (8%) had multiple recurrent subluxations after surgery. Postsurgical recurrent instability was significantly associated with preoperative episodes of subluxation. However, all patients with rare subluxation had an excellent functional result.
Cryotherapy: An Effective Modality for Decreasing Intraarticular Temperature after Knee Arthroscopy
Authors: Martin Stephanie S. , Spindler Kurt P. , Tarter Jeremy W. , Detwiler Ken , Petersen Hilary Ann
Published: July 2017

Cryotherapy is a modality commonly used after arthroscopic procedures. We divided 17 patients into two groups after routine knee arthroscopy: 12 patients were immediately treated with ice and 5 control patients were treated without ice for the first hour. In all patients, thermocouple probes were placed intraarticularly into the lateral gutter of the knee. Ice was placed on the operative knees of the treatment group for 2 hours. The control group had no intervention for the 1st hour and then had ice applied for the 2nd hour. Temperatures were continually recorded every minute for 2 hours. The temperature in the treatment group declined significantly, by 2.2°C (95% confidence interval [—3.6°C, —0.72°C]) over the 1st hour and by 0.79°C (95% CI [—1.8°C, 0.18°C]) over the 2nd hour (P=0.008). The temperature in the control group increased significantly, by 5.0°C (95% CI [2.4°C, 7.5°C]) over the 1st hour (P=0.006). After ice was applied, the temperature fell significantly, by 4.0°C (95% CI [—8.3°C, 0.26°C]) (P=0.06). The difference between the temperature decrease in the treatment group and the increase in the control group at 60 minutes was 7.1°C. This is the first rigorously conducted study in human patients that documents a statistically significant decline in intraarticular knee temperature with the application of ice and compression to the skin. The mechanism by which cryotherapy acts must therefore include the cooling effect on the intraarticular environment and synovium.
Diagnostic Performance of Clinical Examination and Selective Magnetic Resonance Imaging in the Evaluation of Intraarticular Knee Disorders in Children and Adolescents
Authors: Kocher Mininder S. , DiCanzio James , Zurakowski David , Micheli Lyle J.
Published: July 2017

To determine the diagnostic performances of clinical examination and selective magnetic resonance imaging in the evaluation of intraarticular knee disorders in children and adolescents we compared them with arthroscopic findings in a consecutive series of pediatric patients (≤16 years old). Stratification effects by patient age and magnetic resonance imaging center were examined. There were 139 lesions diagnosed clinically, 128 diagnosed by magnetic resonance imaging, and 135 diagnosed arthroscopically. There was no significant difference between clinical examination and magnetic resonance imaging with respect to agreement with arthroscopic findings (clinical examination, 70.3%; magnetic resonance imaging, 73.7%), overall sensitivity (clinical examination, 71.2%; magnetic resonance imaging, 72.0%), and overall specificity (clinical examination, 91.5%; magnetic resonance imaging, 93.5%). Stratified analysis by diagnosis revealed significant differences only for sensitivity of lateral discoid meniscus (clinical examination, 88.9%; magnetic resonance imaging, 38.9%) and specificity of medial meniscal tears (clinical examination, 80.7%; magnetic resonance imaging, 92.0%). For magnetic resonance imaging, children younger than 12 years old had significantly lower overall sensitivity (61.7% versus 78.2%) and lower specificity (90.2% versus 95.5%) compared with children 12 to 16 years old. There was no significant effect of magnetic resonance imaging center. In conclusion, selective magnetic resonance imaging does not provide enhanced diagnostic utility over clinical examination, particularly in children, and should be used judiciously in cases where the clinical diagnosis is uncertain and magnetic resonance imaging input will alter the treatment plan.
Postural Control after Anterior Cruciate Ligament Reconstruction and Functional Rehabilitation
Authors: Henriksson Marketta , Ledin Torbjörn , Good Lars
Published: July 2017

Total sagittal knee laxity and postural control in the sagittal and frontal planes were measured in 25 patients at a mean of 36 months (range, 27 to 44) after anterior cruciate ligament reconstruction and in a control group consisting of 20 uninjured age- and activity-matched subjects. Body sway was measured in the sagittal plane on a stable and on a sway-referenced force plate in single-legged stance, double-legged stance, or both, with the eyes open and closed. Postural reactions to perturbations in the sagittal and frontal planes were recorded in the single-legged stance with the eyes open. Total sagittal plane laxity was significantly greater in the anterior cruciate ligament-reconstructed knee (11.2 mm; range, 6 to 15) than in the uninjured knee (8.9 mm; range, 6 to 12) or in the control group (6.0 mm; range, 5 to 8). In spite of this, the patients, in comparison with the controls, exhibited normal postural control except in two variables—the reaction time and the latency between the start of force movement to maximal sway in the sagittal plane perturbations. This supports the hypothesis that rehabilitation, with proprioceptive and agility training, is an important component in restoring the functional stability in the anterior cruciate ligament-reconstructed knee.
Reproducibility of Anatomic Tibial Landmarks for Anterior Cruciate Ligament Reconstructions
Authors: Hutchinson Mark R. , Bae Taran S.
Published: July 2017

We evaluated the reproducibility of landmarks used for accurate anatomic placement of the tibial tunnel in anterior cruciate ligament reconstruction. Landmarks evaluated were the medial tibial eminence, the posterior cruciate ligament, the “over-the-back” position, the true posterior border of the tibia, and the posterior border of the lateral meniscus. Forty-two pairs of cadaveric knees were dissected, and anatomic measurements were made regarding the anterior cruciate ligament insertion and these various landmarks. Statistical analysis was used to confirm reproducibility and significance. Measurements based on the medial tibial eminence and posterior border of the meniscus were particularly erratic. The most reproducible anatomic landmark was the posterior cruciate ligament. The anterior border of the posterior cruciate ligament was consistently 6.7 mm posterior to the posterior border of the anterior cruciate ligament and 10.9 mm posterior to the central sagittal insertion point of the anterior cruciate ligament. The over-the-back position was consistently in contact with the anterior border of the posterior cruciate ligament if the knee was flexed with a posterior-directed force applied. In this position, the over-the-back position was equally reproducible as compared with the posterior cruciate ligament. Measurements gauged from the true posterior border of the tibia gave a second rigid bony landmark but with a wider standard deviation than the posterior cruciate ligament-based landmarks. The relative anterior-posterior dimension of the tibia did not correlate with the relationship between the anterior cruciate ligament and other anatomic landmarks.
Surgical Treatment of Achilles Tendinitis by Decompression of the Retrocalcaneal Bursa and the Superior Calcaneal Tuberosity
Authors: Yodlowski Marilyn L. , Scheller Arnold D. , Minos Lampros
Published: July 2017

Background

Initial nonoperative treatment of pain at the Achilles tendon, often referred to as “tendinitis,” is not always successful.

Hypothesis

Surgical treatment is effective for patients with insertional tendinitis unrelieved by nonoperative measures.

Study Design

Retrospective cohort study.

Methods

Thirty-five patients (41 feet) who had painful Achilles tendon syndrome unrelieved by 6 months of nonoperative measures were treated surgically. The technique consisted of a single incision along the lateral border of the Achilles tendon. The dissection exposed the retrocalcaneal bursa and fat pad, which were completely excised along with any scarred and thickened paratenon. A partial calcaneal exostectomy of the tubercle was performed.

Results

At a minimum follow-up of 20 months (average, 39), the patients’ pain scores (rated from 0 to 6) improved from 4.7 (SD, 1.1) preoperatively to 1.5 (SD, 1.3); 90% had complete or significant relief of symptoms, 10% felt improved, and none felt unchanged or worse.

Conclusions

Surgical treatment of chronic Achilles tendon pain with resection of the prominent tuberosity, complete debridement of the bursa, excision of thickened, scarred paratenon, and removal of accessible calcific deposits within the tendon is an effective treatment.
Anteroposterior Centering of the Humeral Head on the Glenoid in Vivo
Authors: Schiffern Shadley C. , Rozencwaig Richard , Antoniou John , Richardson Michael L. , Matsen Frederick A.
Published: July 2017

Background

The capsule and ligaments are generally viewed as the primary stabilizers of the glenohumeral joint, but many important activities are performed in midrange positions in which these structures are lax.

Hypothesis

In vivo, the humeral head can be centered in the glenoid, even when the shoulder is in positions in which the capsule is lax and even when the shoulder is passively positioned.

Study Design

Controlled laboratory study.

Methods

We documented the centering of the humeral head in the relaxed shoulders of six subjects using open-magnet magnetic resonance imaging scans.

Results

While these shoulders were passively placed in midrange positions (those not at the extremes of motion), the humeral head center was never more than 2.2 mm from the glenoid center (mean + 0.1 ± 1.2 mm).

Conclusions

The results suggest that mechanisms other than ligamentous restraint, such as the compressive effect of resting muscle tone into the conforming concavity of the glenoid, may be sufficient to maintain centering of the glenohumeral joint. Further exploration of these mechanisms may lead to methods other than ligament tightening or capsular shrinkage for restoration of stability to joints that are unstable in the midrange of motion.

Clinical Relevance

In that many patients with unstable shoulders demonstrate instability in midrange positions, it is hoped that further study of living shoulders will lead to a more effective understanding of the nonligament mechanisms of shoulder stability and the ways in which these stabilizing mechanisms can be restored.
A Biomechanical Analysis of Meniscal Repair Techniques
Authors: Rankin Christopher C. , Lintner David M. , Noble Philip C. , Paravic Vibor , Greer Erin
Published: July 2017

Background

Various methods are available for repair of meniscal tears: a biodegradable meniscal implant without sutures (Biofix meniscus arrow), a suture anchor device (T-fix), and horizontal and vertical mattress sutures.

Hypothesis

There is no difference in repair strength or mode of failure among the techniques compared.

Study Design

Controlled laboratory study.

Methods

Reproducible tears were created in bovine menisci and repaired with each of the techniques. Residual displacement of the tear immediately after repair and the resistance to displacement under load applied perpendicular to the tear were measured and compared.

Results

The residual displacement after repair was highest in the Biofix arrow group (0.70 mm) and lowest in the vertical mattress suture group (0.21 mm). The ultimate strength of repair was strongest for the vertical sutures (202 ± 7 N) and lowest for the arrow and T-fix (95.9 ± 8 N and 99.4 ± 8 N, respectively). The force required to generate 2 mm of tear displacement was greatest for the vertical sutures (143 N) and least for the arrow (43.6 N).

Conclusions

Suture techniques were stronger at all levels of testing.

Clinical Relevance

Knowledge of biomechanical characteristics aids the surgeon in choosing the appropriate technique for each situation.
Bone-Patellar Tendon-Bone Grafts for Anterior Cruciate Ligament Reconstruction
Authors: Honl Matthias , Carrero Volker , Hille Ekkehard , Schneider Erich , Morlock Michael M.
Published: July 2017

Background

Secure fixation is an important factor in the success of anterior cruciate ligament reconstruction.

Hypothesis

There is no difference in the mechanical behavior of reconstructions from method of fixation or method of testing.

Study Design

Controlled laboratory study.

Methods

Anterior cruciate ligament reconstructions were performed with bone-patellar tendon-bone grafts in 48 human cadaveric knees. Three different fixation methods (Endobutton, interference screw, suture-post fixation) were compared under failure tensile loading and cyclic submaximal tensile loading.

Results

No difference was observed in ultimate load among the three techniques. Stiffness of the grafts was significantly lower for the suture technique than for the interference screw technique. Cyclic loading revealed significantly different failure rates: 0% of the Endobutton, 38% of the interference screw, and 100% of the suture-post groups. The relative movement of the femoral bone plug and the migration of the bone plug out of the femoral canal were lowest in the interference screw group.

Conclusions

The suture-post fixation is not recommended. The interference screw technique showed the best results, but results were age-dependent, suggesting its best use is in younger patients. The Endobutton technique is recommended for older patients.

Clinical Relevance

Results of testing are useful to the surgeon in making a choice of reconstruction technique.
Quantitative Review of Operative and Nonoperative Management of Achilles Tendon Ruptures
Authors: Wong Jason , Barrass Victoria , Maffulli Nicola
Published: July 2017

Background

There is no consensus on the best method for management of acute Achilles tendon ruptures. Individual preferences, drawn from experience and study, determine whether treatment is operative or nonoperative.

Purpose

Our goal was to review the literature to try to determine what management method was the most popular and effective. We wanted to ascertain the best results in terms of complication rates and patient outcomes.

Study Design

Retrospective review of retrospectively and prospectively collected data.

Methods

We analyzed 125 articles in peer-reviewed journals for year of publication, patient numbers, sex, management method, follow-up complications, and patient satisfaction. Each article was graded using a validated methods score. Methods, patient satisfaction, and complication rates were correlated with the year each article was published.

Results

Skin-healing complications were lowest in conservatively managed patients (3 of 578, 0.5%) and highest in open repair and immobilized patients (543 of 3718, 14.6%). General complication rates were lowest in open repair and early-mobilization groups (16 of 238, 6.7%) and highest in percutaneous and early-mobilization groups (19 of 122, 15.6%). Rerupture rates were highest in immobilized conservative management groups (62 of 578, 10.7%) and lowest in groups with external fixation (0%).

Conclusions

In general, the number of publications reporting Achilles tendon ruptures is increasing, the quality of articles is increasing, and the trend for the number of reported complications is decreasing. The published articles had a low methods score (mean, 50.9; range, 25 to 77) and showed a trend toward earlier mobilization. Open repair and early mobilization give the best functional recovery and an acceptable complication rate.
A Review of the Special Tests Associated with Shoulder Examination
Authors: Tennent T. Duncan , Beach William R. , Meyers John F.
Published: July 2017

Careful examination of the shoulder is an essential component in forming a diagnosis of problems in this area. A number of tests have been described that are claimed to improve diagnostic accuracy by specifically examining one component of the shoulder complex. Many of these tests are eponymous, and there is confusion about not only how to perform them but also what conclusion to draw from the results. This article attempts to clarify the tests used to examine the rotator cuff by presenting them as described by the original authors with the additional aim of providing a source for those wishing to refresh their knowledge without the need to refer to the original source material.
Laser Capsulorrhaphy for Multidirectional Instability of the Shoulder
Authors: Joseph Thomas A. , Williams James S. , Brems John J.
Published: July 2017

Background

Clinical data on the efficacy of laser capsulorrhaphy for the treatment of multidirectional instability of the shoulder are limited.

Hypothesis

The diagnosis of multidirectional instability includes a spectrum of pathologic symptoms that warrants subclassification; laser capsulorrhaphy alone is not uniformly effective for all subtypes.

Study Design

Retrospective review of prospectively collected data.

Methods

Twenty-five shoulders in 21 patients were treated with laser capsulorrhaphy for multidirectional instability. Functional outcomes at a mean duration of 32 months' follow-up (range, 24 to 48 months) were recorded.

Results

Instability recurred in 60% of patients with congenital multidirectional instability, 17% of patients with acquired multidirectional instability, and 33% of patients with posttraumatic multidirectional instability (overall recurrence rate, 40%). Generalized ligamentous laxity was a risk factor for recurrence. Patient satisfaction rates were 40%, 83%, and 22% for the congenital, acquired, and posttraumatic subgroups. Reasons for dissatisfaction included recurrent instability, persistent pain, and inability to return to athletic activity at desired capacity. The overall mean postoperative Simple Shoulder Test score was 84%. The mean postoperative numeric rating score for pain was 3.3 (10-point scale).

Conclusions

Laser capsulorrhaphy may be effective for patients with acquired multidirectional instability secondary to repetitive microtrauma but is less predictable in the other subgroups.
Influence of Postoperative Immobilization on Tendon Length after Radiofrequency-Induced Shrinkage
Authors: Pötzl Wolfgang , Witt Kai-Axel , Hackenberg Lars , Heusner Till , Steinbeck Joern
Published: July 2017

Background

Despite the widespread use of radiofrequency-induced shrinkage of collagenous tissues, there have been no animal studies on the effects of postoperative immobilization after such treatment.

Purpose

To examine the effects of postoperative immobilization after radiofrequency energy treatment, with special emphasis on any tissue length increases.

Study Design

Controlled laboratory study.

Methods

The right patellar tendon of 60 New Zealand White rabbits was shrunk with a radiofrequency probe. Tendon length was measured intraoperatively before and after shrinkage and via radiographs immediately postoperatively and at 3, 6, and 9 weeks. Twenty rabbits were not immobilized, 20 were immobilized for 3 weeks, and 20 were immobilized for 6 weeks.

Results

In the nonimmobilized limbs, the tendon length increased 34.9% at 3 weeks and another 2.5% at 6 weeks, versus 11.2% at 3 weeks and 6.6% at 6 weeks in the immobilized limbs. Ten of the 20 rabbits that were immobilized for 6 weeks were sacrificed at 9 weeks and were found to have a further length increase of 10.8%. At 9 weeks, the tendons of this group were no longer significantly shorter than the tendons from rabbits that had not been immobilized.

Conclusions

Careful postoperative rehabilitation is imperative after radiofrequency-induced shrinkage. Without protection, exposure to normal physiologic loads places the shrunken tissue at risk of stretching out beyond the preshrinkage length.

Clinical Relevance

Shrunken tissue is at risk of stretching out after radiofrequency-induced shrinkage.
Injury Rates and Profiles in Female Ice Hockey Players
Authors: Schick Deanna M. , Meeuwisse Willem H.
Published: July 2017

Background

Little data exist on injury rates and profiles in female ice hockey players.

Objective

To examine the incidence of injury in female ice hockey players and compare injury rates with those of male players.

Study Design

Prospective cohort study.

Methods

Six male and six female teams from the Canada West Universities Athletic Association were followed prospectively for one varsity season. Preseason medical history forms were completed by each player. Injury report forms and attendance records for each team session were submitted by team therapists.

Results

Male players reported 161 injuries, whereas female players reported 66 injuries. However, the overall injury rates for male (9.19 injuries per 1000 athlete-exposures) and female (7.77 injuries per 1000 athlete-exposures) players did not differ significantly. Ninety-six percent of injuries in female players and 79% in male players were related to contact mechanisms, even though intentional body checking is not allowed in female ice hockey. Women were more likely than men to be injured by contacting the boards or their opponent. Men sustained more severe injuries than women and missed about twice as many sessions (exposures) because of injury. Concussions were the most common injury in female players, followed by ankle sprains, adductor muscle strains, and sacroiliac dysfunction.

Conclusion

Although the injury rate in female ice hockey players was expected to be lower than that in male players because of the lack of intentional body checking, the injury rates were found to be similar.
Effect of Peripheral Afferent Alteration of the Lateral Ankle Ligaments on Dynamic Stability
Authors: Myers Joseph B. , Riemann Bryan L. , Hwang Ji-Hye , Fu Freddie H. , Lephart Scott M.
Published: July 2017

Background

The sensorimotor influence of the lateral ankle ligaments in muscle activation is unclear.

Hypothesis

The lateral ankle ligaments have significant sensorimotor influence on muscle activation.

Study Design

Controlled laboratory study.

Methods

Muscle-firing characteristics in response to a high-speed inversion perturbation and during gait were assessed in 13 normal subjects. Solutions (1.5% lidocaine or a placebo of saline) were injected bilaterally into the anterior talofibular and calcaneofibular ligaments (1.5 ml per ligament) to alter peripheral afferent influence. Subjects were again tested with the same protocol.

Results

The protective response of the anterior tibialis and peroneal muscles during inversion perturbation and mean muscle activation amplitude decreased during running after both injections. After injection, no significant differences were seen for muscle reflex latencies, maximum amplitude, time to maximum amplitude during inversion perturbation, or mean amplitude during walking.

Conclusion

The lateral ankle ligaments have a sensorimotor influence on muscle activation.

Clinical Relevance

Induced edema from the injected solutions may have altered the sensorimotor influence of the lateral ankle ligaments, thereby inhibiting the dynamic ankle stabilizers. This finding suggests that dynamic stability may be compromised because of swelling after joint injury.
Isokinetic Eccentric-to-Concentric Strength Ratios of the Shoulder Rotator Muscles in Throwers and Nonthrowers
Authors: Noffal Guillermo J.
Published: July 2017

Background

One of the possible mechanisms leading to shoulder injury may be a strength imbalance between those muscles that accelerate the upper limb and those responsible for deceleration. Many studies have examined shoulder balance through a concentric strength ratio of external and internal shoulder rotator muscles.

Hypothesis

A functional external eccentric-to-internal concentric ratio may be a better identifier of muscular imbalance in dominant and nondominant shoulders of throwers and nonthrowers.

Study Design

Controlled laboratory study.

Methods

Eccentric external and concentric internal peak torques were measured bilaterally in 59 men (16 throwers and 43 nonthrowers) at 300 deg/sec. Subjects were tested in the supine position with the shoulder abducted to 90° and the elbow flexed to 90°.

Results

Throwers exhibited significantly lower ratios than nonthrowers in their dominant limb; there was no difference between groups for the nondominant limb.

Conclusions

The lower ratio in the throwers’ dominant limb was attributed to significantly greater concentric internal rotation torques without concomitant eccentric external torque gains.

Clinical Relevance

Rehabilitation and injury prevention regimens that include functional exercises to improve eccentric external rotation strength may bring more balance to the dominant shoulder of throwing athletes.
Scapular Muscle Recruitment Patterns: Trapezius Muscle Latency with and without Impingement Symptoms
Authors: Cools Ann M. , Witvrouw Erik E. , Declercq Geert A. , Danneels Lieven A. , Cambier Dirk C.
Published: July 2017

Background

Altered muscle activity in the scapular muscles is commonly believed to be a factor contributing to shoulder impingement syndrome. However, one important measure of the muscular coordination in the scapular muscles, the timing of the temporal recruitment pattern, is undetermined.

Purpose

To evaluate the timing of trapezius muscle activity in response to an unexpected arm movement in athletes with impingement and in normal control subjects.

Study Design

Prospective cohort study.

Methods

Muscle latency times were measured in all three parts of the trapezius muscle and in the middle deltoid muscle of 39 “overhand athletes” with shoulder impingement and compared with that of 30 overhand athletes with no impingement during a sudden downward falling movement of the arm.

Results

There were significant differences in the relative muscle latency times between the impingement and the control group subjects. Those with impingement showed a delay in muscle activation of the middle and lower trapezius muscle.

Conclusion

The results of this study indicate that overhand athletes with impingement symptoms show abnormal muscle recruitment timing in the trapezius muscle. The findings support the theory that impingement of the shoulder may be related to delayed onset of contraction in the middle and lower parts of the trapezius muscle.
A Randomized Comparison of Patellar Tendon and Hamstring Tendon Anterior Cruciate Ligament Reconstruction
Authors: Feller Julian A. , Webster Kate E.
Published: July 2017

Background

Patellar and hamstring tendon autografts are the most frequently used graft types for anterior cruciate ligament reconstruction, but few direct comparisons of outcomes have been published.

Hypothesis

There is no difference in outcome between the two types of reconstruction.

Study Design

Prospective randomized clinical trial.

Methods

After isolated anterior cruciate ligament rupture, 65 patients were randomized to receive either a patellar tendon or a four-strand hamstring tendon graft reconstruction, and results were reviewed at 4, 8, 12, 24, and 36 months.

Results

Pain on kneeling was more common and extension deficits were greater in the patellar tendon group. There were greater quadriceps peak torque deficits in the patellar tendon group at 4 and 8 months but not thereafter. In the hamstring tendon group, active flexion deficits were greater from 8 to 24 months, and KT-1000 arthrometer side-to-side differences in anterior knee laxity at 134 N were greater. Cincinnati knee scores, International Knee Documentation Committee ratings, and rates of return to preinjury activity levels were not significantly different between the two groups.

Conclusions

Both grafts resulted in satisfactory functional outcomes but with increased morbidity in the patellar tendon group and increased knee laxity and radiographic femoral tunnel widening in the hamstring tendon group.
Low Regional Tibial Bone Density in Athletes with Medial Tibial Stress Syndrome Normalizes after Recovery from Symptoms
Authors: Magnusson Håkan I. , Ahlborg Henrik G. , Karlsson Caroline , Nyquist Fredrik , Karlsson Magnus K.
Published: July 2017

Background

Although the exact cause of medial tibial stress syndrome is unclear, changes in bone metabolism are likely to be involved.

Hypothesis

Localized low bone mineral density at the junction of the middle and distal thirds of the tibia in patients with medial tibial stress syndrome develops in conjunction with the symptoms; these changes are reversible and are not inherited.

Study Design

Prospective cohort study.

Methods

Bone mineral density in 14 adult male athletes with long-standing medial tibial stress syndrome was measured when they were symptomatic and after recovery (mean follow-up, 5.7 years). Repeat measurements were also made prospectively in 13 nonathlete control subjects and single measurements were made in 18 healthy athletes.

Results

Bone mineral density was 9% ± 11% higher in the proximal tibia but 11% ± 12% lower in the tibial region corresponding to pain in patients when compared with nonathlete control subjects. It increased by 19% ± 11% in the region of pain after recovery from symptoms and, at follow-up, was no lower than in nonathlete control subjects.

Conclusion

Athletes with medial tibial stress syndrome and increased scintigraphic uptake regain normal tibial bone mineral density after recovery from symptoms. Initially localized low bone mineral density is not an inherited condition, but instead may develop in conjunction with the symptoms.
A Modified Technique of Reconstruction for Complete Acromioclavicular Dislocation: A Prospective Study
Authors: Tienen Tony G. , Oyen Jan F. C. H. , Eggen Peter J. G. M.
Published: July 2017

Background

Many procedures, both nonoperative and operative, have been described for treatment of complete acromioclavicular dislocations. The best primary treatment, however, still remains unclear.

Purpose

We present a new surgical technique in which the clavicle is reduced to an anatomic position, the coracoacromial ligament is transferred to the clavicle, and acromioclavicular joint fixation is accomplished with the use of absorbable, braided suture cord.

Methods

Twenty-one patients underwent the modified technique of reconstruction. Patients were included only if they had sustained a Rockwood type V acromioclavicular dislocation and were extremely active in competitive sports before dislocation occurred.

Results

Eighteen patients returned to their sports without pain within 2.5 months after operation. The mean follow-up was 35.7 months. The average Constant score at last follow-up was 97. Radiographs taken at this time confirmed anatomic reduction in 18 patients, residual subluxation in 2 patients, and, in 1 patient, redislocation of the joint that occurred because of infection. Six patients had radiographic evidence of coracoclavicular ossifications. All patients developed a wide scar.

Conclusions

Considering its operative simplicity, the advantage of absorbable augmentation of the clavicular reduction, and the low rate of recurrence, this technique may be an attractive alternative in this particular group of patients.
Effects of Braiding on Tensile Properties of Four-Strand Human Hamstring Tendon Grafts
Authors: Millett Peter J. , Miller Bruce S. , Close Matthew , Sterett William I. , Walsh William , Hawkins Richard J.
Published: July 2017

Background

Anterior cruciate ligament reconstruction is commonly performed with autogenous hamstring tendon grafts.

Purpose

To ascertain the effects of braiding on ultimate tensile strength and stiffness of hamstring tendon graft.

Study Design

Controlled laboratory study.

Methods

Sixteen fresh-frozen semitendinosus and gracilis tendons were harvested from eight matched (right and left) human cadaveric specimens. Both sets of hamstring tendons from each matched pair were doubled, creating a four-strand graft. Grafts were then randomized so that one graft from each matched pair was braided and the other remained unbraided. The diameter of each graft construct was recorded. Grafts were tested to failure on a materials testing machine.

Results

There were no significant differences in cross-sectional area before or after braiding. Fifteen of 16 tendons failed midsubstance; 1 failed at the lower clamp. Braiding reduced the initial tensile strength and stiffness of human hamstring tendon grafts in this study by 35.0% and 45.8%, respectively.

Conclusions

Braiding may place the collagen fibers in a suboptimal orientation for loading that results in a weaker graft. We do not recommend the use of braiding if the strongest, stiffest initial graft is desired.