bluuebunny/crossref_metadata_2025 huggingface dataset:
Biomechanical Comparisons of Three Posterior Cruciate Ligament Reconstruction Procedures with Load-Controlled and Displacement-Controlled Cyclic Tests
Authors: Kitamura Nobuto , Yasuda Kazunori , Yamanaka Masanori , Tohyama Harukazu
Published: July 2017

Background: Biomechanical behaviors of posterior cruciate ligament reconstructions under cyclic loading have not been sufficiently clarified.

Hypothesis: Biomechanical behaviors of the reconstruction that involves use of flexor tendons and an Endobutton are significantly different under cyclic loading from behaviors of the two standard reconstructions in which bone-patellar tendon-bone graft is used.

Study Design: Controlled laboratory study.

Methods: In a porcine model, the tendon/Endobutton reconstruction, the tendon-bone/interference screw reconstruction, and the tendon-bone/tibial-inlay reconstruction were biomechanically compared by using two cyclic tests. In each group of 15 specimens, 5 knees underwent tensile testing without cyclic loading, and the remaining 10 underwent the same tensile test after 5000 cycles of load-controlled or displacement-controlled loading.

Results: At the 5000th cycle, the peak displacement or the peak load was affected by each type of cyclic loading to a significantly greater degree in the knees with the tendon/Endobutton procedure than in the knees reconstructed with the other two procedures.

Conclusions: Plastic deformation occurred more easily during cyclic loading in the knees with the tendon/Endobutton reconstruction than in the knees with the tendon-bone reconstructions.

Clinical Relevance: When the tendon/Endobutton reconstruction is used, a longer period of postoperative immobilization is necessary.
Topical Nitric Oxide Application in the Treatment of Chronic Extensor Tendinosis at the Elbow
Authors: Paoloni Justin A. , Appleyard Richard C. , Nelson Janis , Murrell George A. C.
Published: July 2017

Background: Extensor tendinosis (“tennis elbow”) is a degenerative overuse tendinopathy of the wrist extensors at their attachment to the lateral humeral epicondyle. No treatment has been universally successful. Topical application of nitric oxide has been used effectively to treat fractures and cutaneous wounds in animal models, presumably by stimulation of collagen synthesis in fibroblasts.

Purpose: To determine whether topical nitric oxide can improve outcome of patients with extensor tendinosis.

Study Design: Prospective, randomized, double-blinded clinical trial.

Methods: Eighty-six patients with extensor tendinosis were randomized into two equal groups; both were instructed to perform a standard tendon rehabilitation program. One group received an active glyceryl trinitrate transdermal patch, and the other group received a placebo patch.

Results: Patients in the glyceryl trinitrate group had significantly reduced elbow pain with activity at 2 weeks, reduced epicondylar tenderness at 6 and 12 weeks, and an increase in wrist extensor mean peak force and total work at 24 weeks. At 6 months, 81% of treated patients were asymptomatic during activities of daily living, compared with 60% of patients who had tendon rehabilitation alone.

Conclusions: Application of topical nitric oxide improved early pain with activity, late functional measures, and outcomes of patients with extensor tendinosis.
Stress Injuries to Bone in College Athletes
Authors: Arendt Elizabeth , Agel Julie , Heikes Christie , Griffiths Harry
Published: July 2017

Background

No comprehensive studies have been published on stress injuries to bone in college athletes.

Purpose

To review, in a college athlete population, the epidemiologic aspects of stress injuries to bone, and to examine a subset of patients who were treated with a uniform protocol for return to activities, with magnetic resonance imaging as the primary tool for diagnosis.

Study Type

Retrospective review.

Methods

Ten years of medical records from a Division I college institution were reviewed. Location and grade of stress injury to bone and duration of disability were recorded. All injured athletes followed the same treatment program, with the exception of football players, who were excluded from the return to sport analyses.

Results

Seventy-four athletes had lower extremity symptoms consistent with stress injury to bone. Diagnosis was confirmed in 68 of these athletes, 61 via magnetic resonance imaging, 6 via positive radiographs only, and 1 via bone scan only. Distance runners accounted for the most stress injuries to bone for both men and women. The tibia (37%) was the most frequently involved bone; however, as an anatomic region, the foot (44%) was the site of the most stress injuries. There was a significant correlation between grade of injury and time to full return to activity.

Conclusions

The grading system used at this institution is a standardized tool that can be used to predict time to return to sport. A standardized rehabilitation protocol allowed for an appropriate plan to return the athletes to pain-free competition.
Nonunion of Olecranon Stress Fractures in Adolescent Baseball Pitchers
Authors: Rettig Arthur C. , Wurth Todd R. , Mieling Paul
Published: July 2017

Background

Adolescent athletes participating in overhead throwing sports suffer a variety of overuse elbow injuries, many of which have been well described in the literature. Nonunion stress fractures of the olecranon across the epiphyseal plate, however, have received little attention.

Purpose

To describe this unusual clinical entity in the differential diagnosis of the adolescent athlete with elbow pain and to demonstrate that operative treatment is an effective means of quickly and safely returning the patient to sporting activities.

Study Design

Case series; Level of evidence, 4.

Methods

Five adolescent baseball pitchers (mean age, 15 years) who suffered chronic elbow pain and who were diagnosed with olecranon epiphyseal stress fracture nonunions were treated with open reduction and internal fixation using a 7.0 cancellous screw and washer with or without 18-gauge tension banding.

Results

Return to preoperative range of motion was achieved at a mean of 8.6 weeks (range, 3.4-16.6 weeks). Patients were clinically asymptomatic at a mean of 11 weeks (range, 7.7-13.6 weeks) after surgery. Radiographic evidence of stress fracture union was achieved at a mean of 15.4 weeks (range, 6.1-33 weeks), including 1 patient with a delayed union according to radiographs, which healed at 33 weeks. Patients were started on a light strengthening program at 5 to 7 weeks and a throwing progression program at 15.6 weeks (range, 6.4-28.1 weeks). All 5 patients were able to return to their previous level of activities, with a mean return time of 29.4 weeks (range, 18.9-40.4 weeks).

Conclusion

Surgical management of olecranon apophysis stress fractures provided excellent results with minimal complications in this series of 5 consecutive cases.
Occurrence of Cervical Spine Injuries During the Rugby Scrum
Authors: Wetzler Merrick J. , Akpata Toks , Laughlin William , Levy Andrew S.
Published: July 2017

A retrospective study of cervical spine injuries that occurred during the rugby scrum in the United States was undertaken. In the U.S., from 1970 to 1996, 36 (58%) of the 62 documented injured players injured their cervical spines during the scrum. Thirty-five men (97%) and one woman (3%) were injured. Twenty-three of the injuries (64%) occurred when the opposing packs came together (engagement), and 13 (36%) occurred when the scrum collapsed. Twenty-eight (78%) hookers, seven (19%) props, and one (3%) second-row player were injured. Twenty (56%) hookers and three (8%) props were hurt during engagement. Eight hookers (22%), four props (11%), and one second-row player (3%) were injured when the scrum collapsed. Significantly more injuries occurred during engagement than during collapse, and hookers were injured significantly more than props. We conclude that in the rugby scrum in the U.S., the hooker suffers most of the cervical spine injuries (78% in this study) and this position is by far the most vulnerable. This study should be used to develop rugby law (rule) changes and educate players, coaches, and referees in United States rugby.
Throwing Fracture of the Humeral Shaft
Authors: Ogawa Kiyohisa , Yoshida Atsushi
Published: July 2017

Ninety patients with humeral shaft fractures sustained during throwing were analyzed to determine what caused their injuries. All patients were recreational baseball players: 89 were men and 1 was a woman. The average age was 25 years (range, 12 to 43). The throwing style, type of pitch, fielding position, and type of ball used varied; however, the patients sustained their fractures while performing a hard throw in 87 (97%) of the occurrences. The actual courses of the balls thrown ranged from sideways to straight forward. All fractures were external rotation spiral fractures; 25 patients (28%) had a medial butterfly fragment, and 14 patients (16%) had radial nerve palsy. Fractures were most likely to have occurred in the distal half of the humerus, although they occurred frequently in the proximal half in patients in their early teens. We conclude that 1) the fracture can occur at any time during the acceleration phase before ball release, 2) this type of fracture can occur in any recreational baseball player attempting to perform a hard throw, and 3) the cause of this fracture is the throwing action itself.
Clinical, Functional, and Radiographic Assessments of the Conventional and Modified Boyd-Anderson Surgical Procedures for Repair of Distal Biceps Tendon Ruptures
Authors: D'Arco Patrick , Sitler Michael , Kelly John , Moyer Raymond , Marchetto Paul , Kimura Iris , Ryan Jeff
Published: July 2017

The purpose of this study was to evaluate the clinical, functional, and radiographic outcomes of the conventional and modified Boyd-Anderson procedures for repair of distal biceps tendon ruptures. Thirteen of 18 men who underwent surgical repair for unilateral distal biceps tendon ruptures at one university center participated in the study. In general, follow-up outcomes were favorable with respect to return to premorbid activity levels, patient satisfaction with surgical outcome, and overall clinical results. Elbow flexion, forearm supination, and upper extremity functional concentric peak torque and range of motion results were not significantly different between the surgical and nonsurgical arms when dominance was controlled as a confounding factor. Radiographic findings revealed no clinically remarkable signs of heterotopic ossification or proximal radioulnar synostosis. Results of the study reveal that the conventional and modified Boyd-Anderson procedures are clinically, functionally, and radio-graphically efficacious for repair of distal biceps tendon ruptures.
Three-Dimensional Knee Joint Kinetics During a Golf Swing
Authors: Gatt Charles J. , Pavol Michael J. , Parker Richard D. , Grabiner Mark D.
Published: July 2017

This study characterized knee joint kinetics during a golf swing and determined the influence of shoe type and golfer skill on the peak knee joint loads. Thirteen golfers each hit a golf ball using a five iron under two footware conditions: spiked and spikeless golf shoes. Data from a video-based motion capture system and force plates were used to compute the knee joint kinetics. Mean peak forces and moments differed significantly between the lead and trail knees, but these peak loads were not significantly affected by shoe type. Only the lead knee flexion and internal rotation moments were significantly correlated to skill level. The magnitude of some of the peak loads at the knee during the golf swing approached those reached during activities prohibited until late-stage knee rehabilitation. We concluded the following: The type of shoe worn and the skill level of the golfer need not be considered in deciding time to return to golfing; however, the leg that is recovering from surgery or injury should be considered. The most stressful phase of the golf swing, relative to the knee, is the downswing. There is probably no “normal” swing; each golfer seems to possess consistent, characteristic, patterns of knee loading.
Articular Cartilage Repair
Authors: Newman Alan P.
Published: July 2017

Articular cartilage can tolerate a tremendous amount of intensive and repetitive physical stress. However, it manifests a striking inability to heal even the most minor injury. Both the remarkable functional characteristics and the healing limitations reflect the intricacies of its structure and biology. Cartilage is composed of chondrocytes embedded within an extracellular matrix of collagens, proteoglycans, and noncollagenous proteins. Together, these substances maintain the proper amount of water within the matrix, which confers its unique mechanical properties. The structure and composition of articular cartilage varies three-dimensionally, according to its distance from the surface and in relation to the distance from the cells. The stringent structural and biological requirements imply that any tissue capable of successful repair or replacement of damaged articular cartilage should be similarly constituted. The response of cartilage to injury differs from that of other tissues because of its avascularity, the immobility of chondrocytes, and the limited ability of mature chondrocytes to proliferate and alter their synthetic patterns. Therapeutic efforts have focused on bringing in new cells capable of chondrogenesis, and facilitating access to the vascular system. This review presents the basic science background and clinical experience with many of these methods and information on synthetic implants and biological adhesives. Although there are many exciting avenues of study that warrant enthusiasm, many questions remain. These issues need to be addressed by careful basic science investigations and both short- and long-term clinical trials using controlled, prospective, randomized study design.
The Deltoid Muscle Origin
Authors: Torpey Brian M. , Ikeda Kazuo , Wang Michael , van der Heeden Dingeman , Chao Edmund Y. S. , McFarland Edward G.
Published: July 2017

The histologic characteristics of the deltoid muscle attachment to nine cadaveric acromia were studied using light microscopy. The deltoid muscle attaches to the anterior and lateral acromion primarily by direct tendinous attachment. The muscle attaches to the dorsal side of the acromion by periosteal fiber attachment. In the specimens studied, a hypothetical acromioplasty of 4 mm would release, on average, 41% of the direct fiber attachment, and a 6-mm acromioplasty would release 69% for all zones examined histologically. The functional and clinical effects of these findings are not known, but the deltoid muscle would be released by arthroscopic acromioplasty in areas where bone is removed.
Evaluation of the Intraosseous and Extraosseous Blood Supply to the Distal Femoral Condyles
Authors: Reddy Ashok S. , Frederick Robert W.
Published: July 2017

Osteonecrosis of the distal femur occurs more often in the medial femoral condyle than in the lateral femoral condyle, but the vascular supply to these regions has not previously been described. Twelve fresh adult cadaver legs were injected with india ink or latex via the femoral artery and then meticulously dissected to evaluate the extraosseous blood supply. After all soft tissue was removed, the intraosseous blood supply was evaluated using a modified Spateholtz technique. The vascular structures at risk during posterior cruciate ligament reconstruction were also identified. The analysis of the extraosseous arterial supply demonstrated that the superior and inferior lateral genicular arteries combine to supply the lateral femoral condyle. The medial femoral condyle is supplied primarily by the superior medial genicular artery and other lesser branches of the popliteal artery. The intraosseous supply to the lateral condyle was shown to consist of an arcade of vessels providing multiple branches to the subchondral bone with no obvious “watershed” region of limited vascularity. The intraosseous supply to the medial condyle appeared to consist of a single nutrient vessel supplying the subchondral bone with an apparent watershed area of limited supply. A potentially significant difference exists between the intraosseous and extraosseous blood supply to the medial and lateral femoral condyles that may explain the higher frequency of ischemic events occurring in the medial femoral condyle. The close proximity of the extraosseous vessels to the medial femoral condyle and the standard femoral tunnel used during posterior cruciate ligament reconstruction may explain the occurrence of avascular necrosis after this procedure.
Elbow Valgus Stress Radiography in an Uninjured Population
Authors: Lee Guy A. , Katz Stephen D. , Lazarus Mark D.
Published: July 2017

Valgus instability of the elbow joint is a clinical diagnosis. However, many authors describe valgus stress radiographs as an aid in making this diagnosis. We studied valgus stress radiographs of 20 men (40 elbows) and 20 women (40 elbows), none with a history of elbow trauma or instability. The medial ulnohumeral distance was measured with no stress, valgus stress by gravity, and an applied valgus stress of 25 N (approximately 5 pounds). Measurements were made with the elbow positioned in extension and in 30° of flexion. The increase in medial ulnohumeral gapping with either gravity or 5 pounds of stress was statistically significant at both extension and 30° of flexion compared with the unstressed condition. The difference in ulnohumeral gapping between gravity stress and 5 pounds of valgus stress in extension and in 30° of flexion was also significant. We found no differences with regard to hand dominance or sex. We conclude that uninjured elbows have significant medial ulnohumeral gapping on valgus stress radiography. Although this is an important tool in diagnosing valgus instability of the elbow, it may yield a false-positive assessment of valgus instability. Valgus stress radiographs comparing contralateral elbows may reduce the false-positive rate since there appears to be no significant difference in medial ulnohumeral gapping between the two elbows.
Distal Biceps Brachii Tendon Repair
Authors: Berlet Gregory C. , Johnson James A. , Milne Andrew D. , Patterson Stuart D. , King Graham J. W.
Published: July 2017

Clinical reports suggest that suture anchors can simplify repair of distal biceps tendon avulsions. In this study, fixation strengths of Mitek and Statak suture anchors were compared with strength of reattachment using transosseous suture tunnels in eight cadaveric radii. Cyclic loading and load-to-failure testing were performed: No specimen failed during testing to 50 N for 3600 cycles; however, four of the Mitek anchors and one of the Statak anchors protruded out of the medullary canal. The mean load to failure of the Mitek suture anchor complexes was 220 54 N, that of the Statak suture anchor complexes was 187 64 N, and that of the transosseous sutures was 307 142 N. There was no significant difference in the failure load or mechanism of failure between the Statak and Mitek anchors. Transosseous sutures failed at significantly greater loads on static testing than the suture anchors. Cyclic loading results suggest that the bony fixation achieved using these three techniques should be sufficient to allow immediate passive mobilization of the elbow after surgery. Protrusion of the suture anchors out of the tuberosity during cyclic loading is a concern because of potential development of a gap at the repair site and interference with forearm rotation.
Different Regional Healing Rates with the Outside-In Technique for Meniscal Repair
Authors: van Trommel Michiel F. , Simonian Peter T. , Potter Hollis G. , Wickiewicz Thomas L.
Published: July 2017

Fifty-one patients with meniscal repair using the outside-in technique were reassessed with second-look arthroscopic procedures (N 15), arthrographic examination (N 41), magnetic resonance imaging (N 36), or a combination of these techniques. Forty-one medial and 10 lateral menisci were repaired. The average clinical follow-up was 15 months (range, 3 to 80). Forty-five of 51 patients had tears that were located in or extended into the posterior horn of the medial or lateral meniscus. Complete healing occurred in 23 menisci (45%), partial healing was observed in 16 (15 medial, 1 lateral) (32%), and no healing occurred in 12 (24%). Remarkably, in all 15 patients who had tears extending from the posterior to the middle third of the medial meniscus that were partially healed, it was always the posterior third that had not fully healed. This finding is statistically significant. In addition, the middle third of these menisci had not fully healed in five patients. No healing occurred in the two patients with tears in the posterior third of the medial meniscus. Poor healing with the outside-in technique was observed in patients with tears into the posterior horn of the medial meniscus. For tears in the middle and anterior portion of the medial meniscus, as well as all lateral meniscus tears, the outside-in technique is our current method of choice.
Meniscal Repair in the Young Athlete
Authors: Mintzer Craig M. , Richmond John C. , Taylor Jeffrey
Published: July 2017

Twenty-nine meniscal repairs in 26 patients 17 years of age or younger were performed using arthroscopic techniques. Clinical follow-up examinations were performed and the SF-36 Health Status Survey and International Knee Documentation Committee evaluation form were administered. A Lysholm score was determined for each patient. All 26 patients were seen for follow-up at an average of 5.0 years (range, 2.0 to 13.5). All patients had a full range of motion with no effusion, joint line tenderness, or McMurray sign present at the time of examination. No patient experienced symptoms of locking. No patient underwent repeat surgery for a nonhealed meniscal repair. The clinical healing rate in this group was 100%. The SF-36 data demonstrated an average physical functioning score of 91 and an average role physical score of 91. The average Lysholm score was 90. Twenty-two patients (85%) were performing level I activities based on the International Knee Documentation Committee rating. Excellent rates of healing, even higher than those obtained in the adult population, can be obtained with meniscal repairs performed in this young age group.
Acute Skier's Thumb Repaired With a Proximal Phalanx Suture Anchor
Authors: Zeman Craig , Hunter Robert E. , Freeman John R. , Purnell Mark L. , Mastrangelo Jackie
Published: July 2017

The purpose of this study was to determine the functional outcome of a surgical technique for the repair of injuries of the ulnar collateral ligament of the thumb. A 14-point questionnaire was developed to determine functional outcome after surgical repair of acute ulnar collateral ligament rupture. Early ulnar collateral ligament repair was performed on 58 patients with grade III sprains (complete rupture) of the ligament using a new technique that employs a suture anchor for fixation. Forty-five patients were interviewed at a minimum postoperative interval of 12 months and were included in this study. Forty-four patients (98%) believed they had a stable repair, were satisfied with their surgery, and would have it again if necessary. Forty-four patients (98%) were not hindered in their day-to-day activities and had a functional range of motion. Mild discomfort was felt by eight of our patients (17%), but only three patients (7%) had pain with activities. The average time to return to skiing was 1.7 days. The use of a suture anchor provided a strong and stable repair if the surgery was performed early.
Quantitative Analysis of Nerve Changes in the Lateral Retinaculum in Patients with Isolated Symptomatic Patellofemoral Malalignment
Authors: Sanchis-Alfonso Vicente , Roselló-Sastre Esther , Monteagudo-Castro Carlos , Esquerdo José
Published: July 2017

Neural damage in 16 lateral retinacula excised at the time of Insall proximal realignments or isolated lateral retinacular releases performed in patients with symptomatic patellofemoral malalignment was evaluated by means of conventional histology and immunohistochemical and morphometric analyses. A relationship between clinical and histologic findings was found. An increase in the proportion of innervated tissue was correlated with anterior knee pain syndrome. We found a significant relationship between total neural area and pain. The group with moderate pain had the highest number of nerves and the highest neural area. In reference to total neural area and pain, there was a significant difference only between the patients with moderate pain and those with light pain, but not between patients with severe pain and those with moderate pain. The group with severe pain also showed a high neural area, although with a lower number of nerves. The severe-pain group had the largest nerves (24% of nerve fibers surpassing 25 m diameter) in a zonal disposition, in which there were groups of nerve fibers in some fields and no nerve fibers in others. The group with moderate pain had an increase in medium and small nerve fibers (mean diameter, 18 m), predominantly of tiny perivascular fibers. Moreover, we believe that instability in patients with patellofemoral malalignment can be explained in part because of loss of proprioception due to neural damage.
The Effect of Anabolic Steroids and Corticosteroids on Healing of Muscle Contusion Injury
Authors: Beiner John M. , Jokl Peter , Cholewicki Jacek , Panjabi Manohar M.
Published: July 2017

The effect of an anabolic steroid (nandrolone decanoate, 20 mg/kg) and a corticosteroid (methylprednisolone acetate, 25 mg/kg) on healing muscle injured with a drop-mass technique in a reproducible muscle contusion injury model in the rat was studied. Healing was determined by measuring active contractile tension in each muscle and histologic analysis. At day 2, the corticosteroid group showed significant improvement in both twitch and tetanic strength relative to the controls. At day 7, this effect was reversed and the corticosteroid muscles were significantly weaker than the control muscles, but there was still no significant effect seen in the anabolic steroid group. At day 14, the corticosteroid muscles were totally degenerated, with disorganized muscle fiber architecture. The anabolic steroid muscles were significantly stronger in twitch, and a similar trend was seen in tetanus relative to control muscles. The results indicate that in an animal model corticosteroids may be beneficial in the short term, but they cause irreversible damage to healing muscle in the long term, including disordered fiber structure and a marked diminution in force-generating capacity. Anabolic steroids may aid in the healing of muscle contusion injury to speed the recovery of force-generating capacity. Although anabolic steroids are considered renegade drugs, they may have an ethical clinical application to aid healing in severe muscle contusion injury, and their use in the treatment of muscle injuries warrants further research.
Mechanical Tensile Properties of the Quadriceps Tendon and Patellar Ligament in Young Adults
Authors: Stäubli Hans U. , Schatzmann Lukas , Brunner Peter , Rincón Liliana , Nolte Lutz-P.
Published: July 2017

We analyzed mechanical tensile properties of 16 10-mm wide, full-thickness central parts of quadriceps tendons and patellar ligaments from paired knees of eight male donors (mean age, 24.9 years). Uniaxial tensile testing was performed in a servohydraulic materials testing machine at an extension rate of 1 mm/ sec. Sixteen specimens were tested unconditioned and 16 specimens were tested after cyclic preconditioning (200 cycles between 50 N and 800 N at 0.5 Hz). Mean cross-sectional areas measured 64.6 8.4 mm2 for seven unconditioned and 61.9 9.0 mm 2 for eight preconditioned quadriceps tendons and were significantly larger than those values of seven unconditioned and seven preconditioned patellar ligaments (36.8 5.7 mm2 and 34.5 4.4 mm2, respectively). Mean ultimate tensile stress values of unconditioned patellar ligaments were significantly larger than those values of unconditioned quadriceps tendons: 53.4 7.2 N/mm2 and 33.6 8.1 N/mm2, respectively. Strain at failure was 14.4% 3.3% for preconditioned patellar ligaments and 11.2% 2.2% for preconditioned quadriceps tendons (P 0.0428). Preconditioned patellar ligaments exhibited significantly higher elastic modulus than preconditioned quadriceps tendons. Based on mechanical tensile properties analyses, the quadriceps tendon-bone construct may represent a versatile alternative graft in primary and revision anterior and posterior cruciate ligament reconstruction.
Structural Properties of Six Tibial Fixation Methods for Anterior Cruciate Ligament Soft Tissue Grafts
Authors: Magen Hugh E. , Howell Stephen M. , Hull Maury L.
Published: July 2017

This study compared the stiffness (K), yield load (YL), and slippage (SL) of six tibial fixation methods. These properties were determined from load-to-failure and cyclic tests of double-looped tendon grafts fixed to both animal and young human tissue. Tandem washers (K 259 N/mm, YL 1159 N, SL 0.5 mm) and the Washerloc (K 248 N/mm, YL 905 N, SL 2.0 mm) were the two best fixations. At 500 N of load, which is the estimated daily tension of an anterior cruciate ligament graft during intensive rehabilitation, slippage was significantly greater in either of the other two methods for sutures tied to a post (4.9 mm), double staples (3.3 mm), and a 20-mm spiked metal washer (3.5 mm). Interference screw fixation performed well in animal tissue (YL 776 N), but was significantly worse in young human tissue (YL 350 N), with 57% of the fixations failing before 500 N of load. Animal tissue should not be used to estimate the performance of interference screw fixation in human tissue. Because 57% of the interference screw fixations using human tissue failed at loads below 500 N, their ability to provide adequate fixation during intensive rehabilitation should be questioned. However, both the Washerloc and tandem washers and screws provide fixation structural properties in young human tibia that should be appropriate for intensive rehabilitation.
Symptomatic Thrower's Exostosis
Authors: Meister Keith , Andrews James R. , Batts Joel , Wilk Kevin , Baumgartner Tom
Published: July 2017

A long-term follow-up was performed on 22 patients treated for a posterior glenoid osteophyte and symptomatic posterior shoulder pain during either the late cocking, acceleration, or follow-through phases of throwing. Arthroscopic evaluation of these patients revealed undersurface tearing of the rotator cuff in all but one. Fifteen patients also had tearing of the posterior labrum. Anterior labral fraying was noted in four patients. Treatment consisted of debridement of the rotator cuff and labral tears. The posterior glenoid osteophyte was removed arthroscopically in 11 patients. Eighteen of 22 throwers treated were available for long-term follow-up at a mean of 6.3 years (range, 1 to 12). Only 10 of 18 (55%) throwers evaluated had returned to their premorbid level of throwing. All 10 were asymptomatic and had maintained a high level of performance for a mean of 3.6 years (range, 1 to 8). At the time of latest follow-up, five players were still participating at the major league level and five had retired. One patient had recurrence of the exostosis 8 years after surgery. Among our patients a trend existed toward a poorer result and failure of return to activity with a posterior osteophyte greater than 100 mm2. A posterior glenoid exostosis, when identified in the symptomatic shoulder of the throwing athlete, can be considered a definite marker of internal impingement.
The Effects of Laser-Induced Collagen Shortening on the Biomechanical Properties of the Inferior Glenohumeral Ligament Complex
Authors: Selecky Mark T. , Vangsness C. Thomas , Liao Wei-Lee , Saadat Vahid , Hedman Thomas P.
Published: July 2017

The purpose of this study was to determine the effects of laser-induced collagen shortening on the biomechanical properties of the inferior glenohumeral ligament complex. Fifty-seven bone-ligament-bone specimens underwent uniaxial tensioning to 10% strain. Approximately half of the specimens then underwent 10% shortening by lasing using a holmium:yttrium-aluminum-garnet laser. Both groups were again tensioned to 10% strain, and then loaded to failure. Ultimate strain and yield strain were significantly higher in the lased specimens than in the nonlased specimens. No significant difference was found for ultimate stress, yield stress, or elastic modulus between the two groups. Failure of the ligament did not appear to occur in the lased areas. The load-to-failure results suggested that the strength of the ligament complex was not significantly compromised by this lasing protocol.
Spinal Injuries in Skiers and Snowboarders
Authors: Tarazi Fadi , Dvorak Marcel F. S. , Wing Peter C.
Published: July 2017

Spinal injuries are among the most devastating injuries associated with recreational sports. Snowboarding spinal injury patterns have not been described. During two seasons (1994 to 1995 and 1995 to 1996), 34 skiers and 22 snowboarders suffered serious spinal injuries (fracture or neurologic deficit or both) at two ski areas in British Columbia, Canada. Ski patrol records, the Provincial Trauma Database, and hospital records were reviewed. Injury rates were based on computerized lift-ticket data and a population estimate of 15% snowboarders (ski patrol observation). The incidence of spinal injury among skiers was 0.01 per 1000 skier-days, and among snowboarders was 0.04 per 1000 snowboarder-days. Mean age was 34.5 years for skiers and 22.4 years for snowboarders. Seventy percent of the skiers were men, whereas all of the snowboarders were men. Jumping (intentional jump 2 meters) was the cause of injury in 20% of skiers and 77% of snowboarders. Neither age nor sex accounted for any significant portion of this difference. The rate of spinal injuries among snowboarders is fourfold that among skiers. Although jumping is the primary cause of injury, it is an intrinsic element of snowboarding. Until research defines effective injury-prevention strategies, knowledge of the risk of snowboarding should be disseminated and techniques for safe jumping should be taught.
The Effects of Dilute Epinephrine Saline Irrigation on the Need for Tourniquet Use in Routine Arthroscopic Knee Surgery
Authors: Olszewski Albert D. , Jones Ronald , Farrell Raymond , Kaylor Kenneth
Published: July 2017

A prospective, randomized, double-blinded study was performed to determine whether dilute epinephrine saline irrigation (1 mg/l) delivered by gravity flow would significantly reduce the need for tourniquet use during routine arthroscopic surgery. One hundred five patients requiring straightforward arthroscopic knee surgery were randomly assigned to either an epinephrine group that received dilute epinephrine irrigation by gravity flow or to a placebo group that received normal saline irrigation by gravity flow. The need for tourniquet use and the tourniquet time, total operative time, and volume of irrigation fluid used were documented and compared between the two groups. A tourniquet was required 50% less often in the epinephrine group than in the placebo group. This difference was found to be statistically significant using the Student's t-test (P< 0.008, α ≤ 0.05). If a tourniquet was required, the presence of dilute epinephrine in the irrigation fluid did not affect the overall tourniquet time or the ratio of tourniquet time to total operative time. We believe this study proved that dilute epinephrine irrigation is effective in decreasing the need for tourniquet use during routine arthroscopic knee surgery.
Eighteen- to Twenty-Five-Year Follow-up After Acute Partial Anterior Cruciate Ligament Rupture
Authors: Messner Karola , Maletius Wolfgang
Published: July 2017

Of 22 consecutive patients with minor knee instability after a partial rupture of the anterior cruciate ligament, all could be reexamined after a mean of 12 years and all but 1 could be reexamined after a mean of 20 years. Three patients needed surgery during the follow-up period, but nobody had an anterior cruciate ligament reconstruction. The Lysholm knee function score was excellent and did not change between 12 and 20 years. Patients had decreased their activities from contact sports before injury to physical fitness activities at the late follow-up. Four patients changed activities because of a knee problem. The quality of life score was somewhat higher than may be expected in an age-matched average population. At late follow-up, eight patients had a 1 Lachman sign, two a 2 Lachman sign, and one a positive pivot shift. Also at late followup, 7 knees showed no signs of radiographic osteoarthrosis, 10 had Fairbank's signs, and 3 had minor and 1 a major joint space reduction. Of the 12 patients with longitudinal radiographic observation, 3 knees had developed a higher degree of osteoarthrosis, and 9 had remained unchanged. The patients had a mean age of 48 years at the late follow-up. This suggests that the results may be regarded as final outcome after this specific knee injury.
Occult Osteochondral Lesions After Anterior Cruciate Ligament Rupture
Authors: Faber Kenneth J. , Dill James R. , Amendola Annunziato , Thain Lisa , Spouge Alison , Fowler Peter J.
Published: July 2017

Twenty-three patients with acute anterior cruciate ligament injuries, normal radiographs, and occult osteochondral lesions revealed by magnetic resonance imaging were reviewed 6 years after initial injury and anterior cruciate ligament hamstring autograft reconstruction. Each patient completed the Mohtadi Quality of Life outcome measure for anterior cruciate ligament deficiency, underwent clinical examination, and had a repeat magnetic resonance imaging scan. The index and follow-up magnetic resonance imaging scans were compared with respect to cartilage thinning and marrow signal. A significant number of patients had evidence of cartilage thinning adjacent to the site of the initial osteochondral lesion. Marrow signal changes persisted in 15 (65%) of the patients. Clinical comparison of patients with normal cartilage with those who had cartilage thinning revealed similar results on both KT-1000 arthrometry and on the Mohtadi outcome measure. This suggests that the initial injury resulted in irreversible changes in the knee. Injuries causing marrow signal changes may result in an alteration in the load-bearing properties of subchondral bone, which in turn allow for changes in the overlying cartilage. Further follow-up will determine the clinical significance of changes detected by magnetic resonance imaging.
Axial and Lateral Radiographs in Evaluating Patellofemoral Malalignment
Authors: Murray Thomas F. , Dupont Jean-Yves , Fulkerson John P.
Published: July 2017

This is a prospective study of 431 patients (862 knees) with patellofemoral pain, patellar dislocation, or other abnormalities of the knee joint. There were 217 asymptomatic knees with no contralateral problems for comparison. All patients had a history and physical and radiographic examination of both knees. The radiographs included standard anteroposterior views, axial views at 30° of knee flexion, and standing lateral views at 0° and 30° of flexion. The presence of patellar tilt or subluxation was noted on the axial view. The lateral view of the patella, with precise overlap of the posterior femoral condyles, allowed determination of relationships between the patella's medial edge, median ridge, and lateral edge to assess patellar tilt. Sixty-two percent of patients with patellar dislocations demonstrated subluxation on the axial view, while 98% demonstrated an abnormal lateral view. Eighteen percent of the control knees revealed evidence of subluxation on the axial view while 35% demonstrated subluxation on the extended lateral view. The axial view demonstrated 62% sensitivity for dislocation, while the lateral view taken in full extension demonstrated 98% sensitivity. The specificity for previous dislocation was 82% for the axial view and 93% for the lateral flexed view. Given the high sensitivity of the lateral view for detecting prior patellar dislocation, a normal result on this view can virtually eliminate the question of previous dislocation. Also, with the high specificity of the axial view and lateral view with knee flexion, the two views combined can confirm a clinical impression of patellofemoral malalignment.
Pull-Out Strength and Stiffness of Meniscal Repair Using Absorbable Arrows or Ti-Cron Vertical and Horizontal Loop Sutures
Authors: Boenisch Uli W. , Faber Kenneth J. , Ciarelli Michael , Steadman J. Richard , Arnoczky Steven P.
Published: July 2017

We tested pull-out strength and linear stiffness of meniscal repair using bioabsorbable arrows and vertical and horizontal loop sutures in fresh-frozen bovine lateral menisci. In phase I, menisci repaired either with 2—0 Ti-Cron vertical or horizontal loop suture, or 10-, 13-, or 16-mm Meniscus Arrows were loaded to failure at 12.5 mm/sec. In phase II, we examined the number of barbs engaged and angle of insertion using 10- and 13-mm arrows. Pull-out strengths of both suture repair groups were significantly higher than those of the arrow groups. Vertical loop sutures were significantly stiffer than horizontal sutures and 10-mm arrows. In phase II, the mean ultimate load to failure for the 10-mm arrows was 35.1 N, significantly stronger than in phase I (18.5 N); however, stiffness remained low (7.9 N/mm). Five arrows in the 13-mm group were inserted parallel to the tibial surface and showed no significant difference from phase I. Five arrows were inserted at more than a 30° angle. This group was significantly weaker than in phase I. Single vertical loop suture showed the highest overall pull-out strength. Although weaker than sutures, arrows should provide sufficient stability for meniscal healing. The number of barbs engaged and angle of insertion are critical.
The Effect of Knee and Ankle Position on Displacement of Achilles Tendon Ruptures in a Cadaveric Model
Authors: Sekiya Jon K. , Evensen Karen E. , Jebson Peter J. L. , Kuhn John E.
Published: July 2017

Using a cadaveric model, we evaluated the effect of knee and ankle position on the displacement of the severed ends of an Achilles tendon transected at three different points. In six cadaveric legs the Achilles tendon was severed transversely, then marked with radiopaque wire suture. The distance between the wire markers was measured on radiographs taken in different positions of ankle and knee flexion. Ankle plantar flexion had a statistically significant effect on decreasing the gap between the severed ends of the Achilles tendon. This effect was clinically significant as, on average, the tendon edges were separated more than 20 mm when the ankle was in the neutral position and were apposed when the ankle was in 60° of plantar flexion. With the ankle fixed in 60° of plantar flexion, knee position had no significant effect on the displacement of the severed ends of the Achilles tendon. Overall, the effect of knee flexion was neither statistically significant nor clinically significant, as the increase in displacement of the severed ends of the Achilles tendon was only 3 mm from 0° to 120° of knee flexion. These results suggest that the nonoperative treatment of Achilles tendon ruptures requires immobilization in maximal ankle plantar flexion, and that immobilization of the knee may not be necessary to achieve tendon-edge apposition.
Snapping Popliteus Tendon Syndrome
Authors: Cooper Daniel E.
Published: July 2017

Six patients with snapping in the knee were evaluated with clinical history, examination, radiographs, and other imaging. All patients were younger than 40 years and none had an arthritic process. Onset was traumatic in three patients, spontaneous in two, and post-surgical in one. The popping was on the direct lateral aspect of the knee. A consistent examination finding was that the popping was more prominent when the knee was loaded with varus stress during passive flexion and extension cycling, and that it was easily palpated midway between the lateral epicondyle and lateral joint line. Four patients were treated nonoperatively and two had operations. Of those treated without surgery, two had spontaneous resolution of the popping, in one the popping persisted, although not symptomatic enough to require surgery, and one had surgery later. In the surgical group, one patient was treated with popliteus tendon release and one with tenodesis of the popliteus tendon to the fibular collateral ligament. Both procedures were curative and neither led to complicating problems. Follow-up information was not available for the patient with late surgery. Snapping of the popliteus tendon should be recognized as a cause of lateral popping in the knee. It is easily confused with more common sources of mechanical symptoms. Awareness will allow accurate diagnosis and treatment, avoiding unnecessary diagnostic arthroscopy.
Eighteen- to Twenty-four-Year Follow-up After Complete Rupture of the Anterior Cruciate Ligament
Authors: Maletius Wolfgang , Messner Karola
Published: July 2017

A unilateral, complete rupture of the anterior cruciate ligament was diagnosed in 60 consecutive patients by arthroscopy within 1 week of trauma. Most ruptured ligaments were treated by acute nonaugmented repair immediately after the arthroscopy. Fifty-five and 56 patients were reevaluated after 12 years and 20 years, respectively. Twenty-five patients (45%) had at least one reoperation during the follow-up period of 20 years, primarily for meniscal problems. Seven patients (13%) had repeat anterior cruciate ligament surgery. The overall Lysholm knee function score remained at a median of 90 points from 12 to 20 years, but patients had decreased their sporting activities from team sports at full rehabilitation to physical fitness activities at the late follow-up. Patients who had repeat surgery had a worse knee function score, were less satisfied with their knees, and also had to change activities and change work more often than patients without reoperation. The majority of patients had, at both follow-up periods, unstable knees. At 20 years, weightbearing radiographs showed slight-to-moderate changes equivalent to osteoarthrosis in 84% (47) of patients and a 32% increase in osteoarthrosis since the 12-year evaluation.
A Developmental Examination of Adolescents'Fears
Authors: Bennett Andrew , Klein Carolyn , Derevensky Jeffrey L.
Published: July 2017

Fear, one of the most powerful of all human emotional reactions, is a normal response to an active or perceived threat that precipitates both physiological and psychological changes. Research with elementary and preschool children has revealed developmental trends in the types and realism of expressed fears. This study examined specific fears of adolescents and the existence of developmental changes and gender differences. Adolescents in grades 7 through 11 (N=478) in a suburban public high school completed a questionnaire that requested that they provide a list of their fears. An analysis of variance revealed that girls reported more fears than boys, and that older students reported more fears than younger students. Results of Chi Square analyses reveal clear developmental trends in the fear of AIDS, drugs, career, and political instability. Gender differences were noted with more females being concerned about peer pressure, the future, and moral and social values.
Testing a Typology of Police Performance Measures: An Empirical Study of Police Services
Authors: Wang XiaoHu , Vardalis James J. , Cohn Ellen G.
Published: July 2017

This research tests a typology used to classify performance measures used in local police departments. This typology classifies performance measures into three categories or domains: objective output measures, objective outcome measures, and subjective outcome measures. Using survey data, the authors test the hypothesis that public officials' preferences of police performance measures can be measured by this three-domain typology and that their preferences can be grouped as output oriented, objective outcome oriented, or subjective outcome oriented. The results indicate that local officials' preferences for police performance measures can be represented with this three-part typology.