bluuebunny/crossref_metadata_2025_split huggingface dataset:
Significance of Ultrasonographically Detected Asymptomatic Tendinosis in the Patellar and Achilles Tendons of Elite Soccer Players: A Longitudinal Study
Authors: Fredberg Ulrich , Bolvig Lars 
Published: July 2017

Background Chronic tendinosis of the Achilles or patellar tendons, or both, is one of the most frequent and severe conditions that affects athletes in sports such as soccer. It can often end an athlete's sports activity. Hypothesis Ultrasonography of asymptomatic tendons can be used to predict which athletes will develop tendon symptoms. Study Design Longitudinal study. Methods Using ultrasonography of the ankle and knee, we examined 54 elite soccer players in the top Danish soccer league before and after a single season (in January and December). Results At the start of the season, ultrasonography had revealed abnormalities in 29% of those examined. Eighteen percent (18 of 98 tendons) were observed to have abnormal sonographic findings in the patellar tendon at the initial examination in January. These athletes were found to have a 17% risk of developing symptomatic jumper's knee during the 12-month season. Eleven percent (11 of 96 tendons) were observed to have abnormal sonographic findings in the Achilles tendon at the initial examination; it was calculated that they had a 45% risk of developing symptoms of Achilles tendinosis. Only one of the players with normal tendons in January actually developed symptoms by the end of the season. Conclusions For the first time it is now possible to identify risk factors for the development of serious tendon disorders in asymptomatic athletes. Future studies may be directed at developing preventive treatment to reduce the risk of chronic, therapy-resistant symptoms of tendinosis and ruptures.
The Effect of Graft-Tunnel Diameter Disparity on Intraosseous Healing of the Flexor Tendon Graft in Anterior Cruciate Ligament Reconstruction
Authors: Yamazaki Shuji , Yasuda Kazunori , Tomita Fumihisa , Minami Akio , Tohyama Harukazu 
Published: July 2017

Background Graft-to-tunnel healing is a significant factor in anterior cruciate ligament reconstruction, but there have been few studies on the effect of graft-tunnel diameter disparity on intraosseous healing of the flexor tendon graft. Hypothesis Graft-tunnel diameter disparity of 2 mm has no effect on the pull-out strength of the graft from the bone tunnel. Study Design Controlled laboratory study. Methods Forty-two beagle dogs were divided into three groups. In each animal, reconstruction was performed in the left knee by using a 4-mm diameter autogenous flexor tendon for groups 1 and 2 and by using a 4-mm wide bone-patellar tendon-bone graft in group 3. A 4-mm diameter tunnel was drilled in the tibia of groups 1 and 3 and a 6-mm diameter tunnel, in group 2. In each group, seven animals were sacrificed at 3 and 6 weeks. Results The perpendicular fibers connecting the graft to the bone were generated in groups 1 and 2, and the number appeared to be higher in group 2, where the space was greater. There was no significant difference in the ultimate failure load between groups 1 and 2 at each period. Conclusion Graft-tunnel diameter disparity of up to 2 mm may not adversely affect intraosseous healing of the flexor tendon graft. Clinical Relevance Surgeons need not be overly concerned about minor graft-tunnel diameter disparities.
Medial Collateral Ligament Reconstruction of the Elbow using the Docking Technique
Authors: Rohrbough Joel T. , Altchek David W. , Hyman Jon , Williams Riley J. , Botts Jonathan D. 
Published: July 2017

Background Medial collateral ligament insufficiency of the elbow with resultant valgus instability in throwing athletes is typically treated with free tendon graft reconstruction as described by Jobe. Hypothesis Improved results could be obtained with the use of the docking technique. Study Design Uncontrolled retrospective review. Methods The study group consisted of 36 athletes who had symptomatic insufficiency of the medial collateral ligament confirmed by magnetic resonance imaging and by surgical findings. Average follow-up was 3.3 years. Key elements of the docking technique included a muscle-splitting approach without routine transposition of the ulnar nerve, routine arthroscopic assessment, treatment of associated lesions, and docking the two ends of the tendon graft into a single humeral tunnel. Results Thirty-three of 36 patients (92%) returned to or exceeded their previous level of competition for at least 1 year, meeting the Conway-Jobe classification criteria of “excellent.” All 22 professional or collegiate athletes returned to or exceeded their previous competition level. Conclusions The docking technique allowed simplified graft tensioning and improved graft fixation.
Arthroscopic Anterior Cruciate Ligament Reconstruction: A Metaanalysis Comparing Patellar Tendon and Hamstring Tendon Autografts
Authors: Freedman Kevin B. , D'Amato Michael J. , Nedeff David D. , Kaz Ari , Bach Bernard R. 
Published: July 2017

Background The best choice of graft tissue for use in anterior cruciate ligament reconstruction has been the subject of debate. Hypothesis: Anterior cruciate ligament reconstruction with patellar tendon autograft leads to greater knee stability than reconstruction with hamstring tendon autograft. Study Design Metaanalysis. Methods A Medline search identified articles published from January 1966 to May 2000 describing arthroscopic anterior cruciate ligament reconstruction with either patellar tendon or hamstring tendon autograft and with a minimum patient follow-up of 24 months. Results There were 1348 patients in the patellar tendon group (21 studies) and 628 patients in the hamstring tendon group (13 studies). The rate of graft failure in the patellar tendon group was significantly lower (1.9% versus 4.9%) and a significantly higher proportion of patients in the patellar tendon group had a side-to-side difference of less than 3 mm on KT-1000 arthrometer testing than in the hamstring tendon group (79% versus 73.8%). There was a higher rate of manipulation under anesthesia or lysis of adhesions (6.3% versus 3.3%) and of anterior knee pain in the patellar tendon group (17.4% versus 11.5%) and a higher incidence of hardware removal in the hamstring tendon group (5.5% versus 3.1%). Conclusions Patellar tendon autografts had a significantly lower rate of graft failure and resulted in better static knee stability and increased patient satisfaction compared with hamstring tendon autografts. However, patellar tendon autograft reconstructions resulted in an increased rate of anterior knee pain.
Muscle Flexibility as a Risk Factor for Developing Muscle Injuries in Male Professional Soccer Players
Authors: Witvrouw Erik , Danneels Lieven , Asselman Peter , D'Have Thomas , Cambier Dirk 
Published: July 2017

Background Muscular tightness is frequently postulated as an intrinsic risk factor for the development of a muscle injury. However, very little prospective data exist to prove this. Hypothesis Increased muscle tightness identifies a soccer player at risk for a subsequent musculoskeletal lesion. Study Design Prospective cohort study. Methods We examined 146 male professional soccer players before the 1999–2000 Belgian soccer competition. None of the players had a history of muscle injury in the lower extremities in the previous 2 years. The flexibility of the hamstring, quadriceps, adductor, and calf muscles of these players was measured goniometrically before the start of the season. All of the examined players were monitored throughout the season to register subsequent injuries. Results Players with a hamstring (N = 31) or quadriceps (N = 13) muscle injury were found to have significantly lower flexibility in these muscles before their injury compared with the uninjured group. No significant differences in muscle flexibility were found between players who sustained an adductor muscle injury (N = 13) or a calf muscle injury (N = 10) and the uninjured group. Conclusions These results indicate that soccer players with an increased tightness of the hamstring or quadriceps muscles have a statistically higher risk for a subsequent musculoskeletal lesion. Clinical Significance Preseason hamstring and quadriceps muscle flexibility testing can identify male soccer players at risk of developing hamstring and quadriceps muscle injuries.
Glenohumeral Translations are Only Partially Restored after Repair of a Simulated Type II Superior Labral Lesion
Authors: Burkart Andreas , Debski Richard E. , Musahl Volker , McMahon Patrick J. 
Published: July 2017

Background The effect on joint stability of repair of type II superior labrum and biceps anchor lesions is unknown. Hypothesis Increased translations of the glenohumeral joint after a simulated type II lesion will be reduced after the lesion is repaired. Study Design Controlled laboratory study. Methods A robotic/universal force-moment testing system was used to simulate load-and-shift and apprehension tests on eight cadaveric shoulders to determine joint kinematics of the shoulder after venting, creation of a type II lesion, and repair of the lesion. Results At 30° of abduction, anterior translation of the vented joint in response to an anterior load was 18.7 ± 8.5 mm and was significantly increased to 26.2 ± 6.5 mm after simulation of a type II lesion. Repair did not restore anterior translation (23.9 ± 8.6 mm) to that of the vented joint. The inferior translation that also occurred during application of an anterior load was 3.8 ± 4.0 mm in the vented joint and increased significantly to 8.5 ± 5.4 mm with a simulated type II lesion. After repair, the inferior translation decreased significantly to 6.7 ± 5.3 mm. Conclusions Repair of a type II lesion only partially restored glenohumeral translations to that of the vented joint. Clinical Relevance Surgical techniques including improved repair of passive stabilizers injured in the type II lesion should be considered.
Comparison of Clinical and Dynamic Knee Function in Patients with Anterior Cruciate Ligament Deficiency
Authors: Patel Rohita R. , Hurwitz Debra E. , Bush-Joseph Charles A. , Bach Bernard R. , Andriacchi Thomas P. 
Published: July 2017

Background Whether passive measures of isokinetic muscle strength deficits and knee laxity are related to the dynamic function of the anterior cruciate ligament-deficient knee remains unclear. Hypotheses Arthrometer measurements are not predictive of peak external knee flexion moment (net quadriceps muscle moment), isokinetic quadriceps muscle strength correlates with peak external knee flexion moment (net quadriceps muscle moment), and isokinetic hamstring muscle strength correlates with peak external knee extension moment (net flexor muscle moment). Study Design Cross-sectional study. Methods Gait analysis was used to assess dynamic function during walking, jogging, and stair climbing in 44 subjects with unilateral anterior cruciate ligament deficiency and 44 control subjects. Passive knee laxity and isokinetic quadriceps and hamstring muscle strength were also measured. Results Arthrometer measurements did not correlate with peak external flexion or extension moments in any of the activities tested or with isokinetic quadriceps or hamstring muscle strength. Test subjects also had a significantly reduced peak external flexion moment during all three jogging activities and stair climbing compared with the control subjects and this was correlated with significantly reduced quadriceps muscle strength. Conclusions Absolute knee laxity difference did not correlate with dynamic knee function as assessed by gait analysis and should not be used as a sole predictor for the outcome of treatment. Patients with greater than normal strength in the anterior cruciate ligament-deficient limb performed low- and high-stress activities in a more normal fashion than those with normal or less-than-normal strength.
Computer Simulations of Patellofemoral Joint Surgery
Authors: Cohen Zohara A. , Henry Jack H. , McCarthy Denise M. , Van Mow C. , Ateshian Gerard A. 
Published: July 2017

Background Variable clinical outcomes of tibial tuberosity transfer surgery have been reported. Hypotheses The biomechanical outcome of surgery is patient-specific; no single procedure produces superior results for all patients. Use of patient-specific computer models can optimize choice of procedure. Study Design Computer simulation study using clinical data. Methods We used patient-specific multibody models of the patellofemoral joints of 20 patients with a diagnosis of patellar subluxation and osteoarthritis. Four tibial tuberosity transfer procedures (two anterior and two anteromedial) were simulated for each patient and compared with their preoperative model. Results When results for all patients were averaged, all simulated operations produced a statistically significant decrease in surface-wide mean contact stress, although no significant difference was found among them. Conclusions The simulated surgical outcomes were patient-specific: no single procedure was consistently superior at decreasing peak or mean stress and each procedure produced a potentially detrimental outcome, an increase in either mean stress or peak stress, in at least one patient. Clinical Relevance Computer simulation may serve as a valuable tool for tailoring procedures to specific patients.
Rotator Cuff Repair
Authors: Waltrip Robert L. , Zheng Nigel , Dugas Jeffrey R. , Andrews James R. 
Published: July 2017

Background The most common complication of rotator cuff repair is structural failure at the repair site. A single-layer repair does not adequately reproduce the anatomic insertion and may not optimize fixation strength. Hypothesis A double-layer rotator cuff repair will have greater initial fixation strength than a single-layer repair. Study Design Controlled laboratory study. Methods Twelve fresh-frozen matched pairs of cadaveric shoulders were repaired by using dual-site fixation with both suture anchors and transosseous tunnels on one side (technique 1). Fixation was achieved by using suture anchors with horizontal mattress sutures and bone tunnels with modified Mason-Allen sutures. Half of the contralateral matched shoulders underwent fixation with suture anchors and simple sutures to simulate commonly used arthroscopic methods (technique 2) and, in the rest, fixation was achieved by using transosseous tunnels and modified Mason-Allen sutures (technique 3). Repaired specimens then underwent cyclic loading at physiologic rates and loads. The number of cycles to failure, which was defined as a 1-cm gap at the repair site, was then recorded. An arbitrary cut-off point of 5000 cycles was chosen. Results The mean number of cycles to failure with technique 1 (3694 ± 1980 cycles) was significantly greater than that with either technique 2 (1414 ± 1888 cycles) or technique 3 (528 ± 683 cycles). Failure was predominantly through bone. Conclusions The initial fixation strength of our double-layer repair exceeds that of isolated single-layer repairs with either suture anchors or transosseous tunnels.
Clinical Outcome of Anterior Cruciate Ligament Reconstruction with Quadrupled Hamstring Tendon Graft and Bioabsorbable Interference Screw Fixation
Authors: Charlton William P. H. , Randolph Donald A. , Lemos Stephen , Shields Clarence L. 
Published: July 2017

Background To date, there has been no publication of clinical follow-up data on patients who have undergone quadrupled hamstring tendon autograft anterior cruciate ligament reconstruction with bioabsorbable screw fixation. Purpose To report the results of quadrupled hamstring tendon autograft anterior cruciate ligament reconstruction with bioabsorbable interference screw fixation. Study Design Retrospective review. Methods Sixty-five patients (66 knees) were retrospectively identified by chart review as having undergone quadrupled hamstring tendon autograft anterior cruciate ligament reconstruction with bioabsorbable interference screw fixation with a minimum 2-year follow-up. Results Data were collected on 48 knees in 47 patients (73%) at an average 30.2 months (range, 24 to 43) after surgery. Thirty-six patients (37 knees) returned for clinical evaluation (56% return) and subjective follow-up only was obtained in 11 patients (17%). The mean Lysolm knee score was 91 (range, 45 to 98), with a mean of 97 for the uninvolved knee. The mean Tegner activity score was 5.7 (range, 3 to 7). The KT-1000 arthrometer mean side-to-side difference for manual maximum displacement was 2.03 mm (range, -1 to 8). The mean International Knee Documentation Committee knee score was 83 (range, 47 to 100). Patients who underwent associated partial meniscectomy or meniscal repair had significantly lower International Knee Documentation Committee scores than patients without associated procedures (P < 0.01). Conclusions Quadrupled hamstring tendon autograft anterior cruciate ligament reconstruction with bioabsorbable interference screw fixation is comparable with other methods of anterior cruciate ligament reconstruction in terms of patient satisfaction, knee stability, and function.
Ulnar and Median Nerve Palsy in Long-distance Cyclists
Authors: Patterson J. Megan M. , Jaggars Marissa M. , Boyer Martin I. 
Published: July 2017

Background Although case reports have identified the presence of distal ulnar nerve sensory and motor dysfunction in long-distance cyclists, the actual incidence of this condition, referred to as “cyclist's palsy,” is unknown. Purpose To determine the incidence of distal ulnar nerve compression in cyclists. Study Design Prospective study. Methods Twenty-five road or mountain bike riders responded to a questionnaire and were then physically examined and interviewed before and after a 600-km bicycle ride. Results Twenty-three of the 25 cyclists experienced either motor or sensory symptoms, or both. Motor symptoms alone occurred in 36% of the hands (11 cyclists) tested; no significant difference in the incidence of motor symptoms was found among cyclists of various experience levels or based on handlebar types (mountain bike versus road bike). Sensory symptoms alone occurred in 10% of hands (four cyclists) tested, with the majority of these being in the ulnar distribution. A significantly higher proportion of mountain bike riders had sensory deficits compared with road bike riders; however, there was no significant difference in the occurrence of sensory deficits based on level of experience. A total of 24% of the hands (eight cyclists) tested experienced a combination of motor and sensory symptoms. These motor and sensory symptoms were equally distributed between road bike riders and mountain bike riders and riders of various experience levels. Conclusions Cyclist's palsy occurs at high rates in both experienced and inexperienced cylists. Steps may be taken to decrease the incidence of cyclist's palsy; these include wearing cycling gloves, ensuring proper bicycle fit, and frequently changing hand position.
The Effect of Femoral Tunnel Position on Graft Forces during Inlay Posterior Cruciate Ligament Reconstruction
Authors: Oakes Daniel A. , Markolf Keith L. , McWilliams Justin , Young Charles R. , McAllister David R. 
Published: July 2017

Background The femoral tunnel may be positioned centrally or eccentrically within the posterior cruciate ligament footprint during a single-bundle posterior cruciate ligament reconstruction. Hypothesis After reconstruction, graft forces are significantly different from those of the native posterior cruciate ligament and are affected by the position of the femoral tunnel. Study Design Controlled laboratory study. Methods The resultant force in the native posterior cruciate ligament was measured in nine cadaveric knees as the knee was flexed from —5° to 120° of flexion. Posterior cruciate ligament reconstruction was performed with the femoral side of the graft positioned centrally and then offset 5 mm eccentric to the central position. Results Mean graft forces were not significantly different between eccentric and central tunnel positions during passive knee extension between 120° and 0° of flexion; at 5° of hyperextension, the eccentric position generated significantly lower graft forces. For both reconstruction techniques, mean graft forces were significantly higher than those for the native posterior cruciate ligament beyond approximately 90° of flexion, for 5 N·m internal and external tibial torque; 5 N·m varus and valgus moment. Conclusions Graft force reductions achieved with the eccentric femoral position appear to be relatively small compared with the forces expected during rehabilitation and activities of daily living. Clinical Relevance After posterior cruciate ligament graft reconstruction, rehabilitation activities that load the knee at high degrees of flexion should be avoided to limit excessive forces on the maturing graft.
Nonoperative Treatment of Acute Rupture of the Achilles Tendon: Results of a New Protocol and Comparison with Operative Treatment
Authors: Weber Martin , Niemann Marco , Lanz Renate , Müller Thorsten 
Published: July 2017

Background Excellent results are reported from both nonoperative and operative treatment of Achilles tendon rupture. Purpose To describe a new nonoperative treatment protocol for Achilles tendon ruptures and compare outcomes with operative treatment. Study Design Retrospective cohort study. Methods We treated 23 patients nonoperatively with an equinus ankle cast and boot and compared their outcome with that of a group of 24 patients previously treated operatively. Muscle strengthening and walking with full weightbearing were started as soon as tolerated in both groups. Follow-up examinations were performed for 18 nonoperatively treated patients after 23 months and for 15 operatively treated patients after 49 months. Results Subsidence of pain, return to unaided walking, and return to work was faster in the nonoperatively treated group. Patient satisfaction, return to sports, and ultimate strength was the same for both groups. The complication rate was similar, except for reruptures: four early in the nonoperative group and one late in the operative group. Two types of reruptures occurred in the nonoperative group: 1) normally healing tendon subjected to new trauma, rerupturing in the healing zone, and achieving a good result with continued nonoperative treatment; and 2) tendon failing proximal to the initial rupture at the muscle-tendon junction, without trauma, requiring operative repair and augmentation. Conclusions Results of operative and nonoperative treatment were equivalent.
Traumatic Anterior Shoulder Dislocation in Adolescents
Authors: Deitch John , Mehlman Charles T. , Foad Susan L. , Obbehat Amir , Mallory Mia 
Published: July 2017

Background Recurrent instability is the most common complication after traumatic anterior shoulder dislocation in young patients. Hypothesis The rate of recurrent instability in a homogeneous population of adolescents after initial traumatic anterior shoulder dislocation is significant and is associated with a guarded prognosis for full recovery. Study Design Retrospective cohort study. Methods We identified 32 patients 11 to 18 years of age treated at our institution for a radiographically documented traumatic anterior shoulder dislocation; we performed a functional outcome assessment on 30 patients with use of two standard scoring systems. Results Overall, instability recurred in 24 of 32 patients, with 23 experiencing at least one recurrent dislocation. Persistent instability led 16 of 32 to undergo a shoulder stabilization procedure. There were no significant differences in the functional outcome of patients who had undergone surgical stabilization and those who were treated nonoperatively. Conclusions The recurrence rate of shoulder instability was 75%. Outcome scores were similar for patients treated with a surgical procedure and those treated nonoperatively. Clinical Significance Treatment efforts must be aimed at optimizing shoulder strength and stability. Prognosis for full recovery remains guarded. Available outcome instruments may not discriminate well between patients who do and do not choose surgery.