bluuebunny/crossref_metadata_2025 huggingface dataset:
Electromyographic Analysis and Phase Definition of the Overhead Football Throw
Authors: Kelly Bryan T. , Backus Sherry I. , Warren Russell F. , Williams Riley J.
Published: July 2017

Background

The phases of the football throw need definition so that muscle activation patterns during the overhead football throw can be fully described.

Hypothesis

Electromyographic analysis of shoulder musculature can better define muscle activation patterns during the football throw.

Study Design

Descriptive anatomic study.

Methods

Videos of 20 elite-level quarterbacks were reviewed to define phases of the overhead football throw; 14 recreational male athletes underwent electromyography and motion analysis testing.

Results

Four sequential phases of the football throw were consistently observed. Early cocking (49% ± 11% of throw) was initiated at rear foot plant and continued to maximal shoulder abduction and internal rotation. Late cocking (20% ± 6%) started at maximal shoulder abduction and internal rotation and ended with maximal shoulder external rotation. The acceleration phase (15% ± 4%) began with maximal shoulder external rotation and ended with ball release. Follow-through (16% ± 5%) was defined as the phase from ball release to maximal horizontal adduction (across the body).

Conclusion

The four phases demonstrated little variation in motion analysis and electromyographic activation between subjects and were associated with muscle activation patterns consistent with upper extremity movements.

Clinical Relevance

A clearer understanding of muscle activation patterns may help to explain patterns of muscle injury and improve rehabilitation protocols in football-throwing athletes.
Physical Therapy for Patellofemoral Pain
Authors: Crossley Kay , Bennell Kim , Green Sally , Cowan Sallie , McConnell Jenny
Published: July 2017

Background

Although physical therapy forms the mainstay of nonoperative management for patellofemoral pain, its efficacy has not been established.

Hypothesis

Significantly more pain relief will be achieved from a 6-week regimen of physical therapy than from placebo treatment.

Study Design

Multicenter, randomized, double-blinded, placebo-controlled trial.

Methods

Seventy-one subjects, 40 years of age or younger with patellofemoral pain of 1 month or longer, were randomly allocated to a physical therapy or placebo group. A standardized treatment program consisted of six treatment sessions, once weekly. Physical therapy included quadriceps muscle retraining, patellofemoral joint mobilization, and patellar taping, and daily home exercises. The placebo treatment consisted of sham ultrasound, light application of a nontherapeutic gel, and placebo taping.

Results

Sixty-seven participants completed the trial. The physical therapy group (N = 33) demonstrated significantly greater reduction in the scores for average pain, worst pain, and disability than did the placebo group (N = 34).

Conclusions

A six-treatment, 6-week physical therapy regimen is efficacious for alleviation of patellofemoral pain.
Simultaneous Bilateral Anterior Cruciate Ligament Reconstruction
Authors: Jari Sanjiv , Shelbourne K. Donald
Published: July 2017

Background

There are no reports on the outcome of bilateral simultaneous anterior cruciate ligament reconstruction.

Hypothesis

There is no difference in outcome between unilateral and simultaneous bilateral operations.

Study Design

Case control study.

Methods

We compared the short-term outcome (mean, 37.2 months) of 28 patients who had bilateral simultaneous reconstructions with that of a matched group of patients who had unilateral reconstruction.

Results

Postoperative narcotic requirements for pain did not differ between groups. The mean quadriceps muscle strength for the simultaneous group was 99% in the right leg and 102% in the left leg compared with the strongest leg preoperatively; the mean for the unilateral group was 99%. The mean modified Noyes score for the simultaneous group was 91.2 points in the left knee and 93.5 points for the right knee; the mean for the unilateral group was 88.7 points. The mean time to return to full-time work and to full sports was 4.1 weeks and 6.1 months for the simultaneous group and 3.0 weeks and 6.3 months for the unilateral group. The mean hospital costs were $6687 and $4307, respectively.

Conclusions

When clinical indications exist, we recommend simultaneous bilateral anterior cruciate ligament reconstruction as opposed to staged procedures because it is a safe, effective, and cost-effective option.
Relationship between Postconcussion Headache and Neuropsychological Test Performance in High School Athletes
Authors: Collins Michael W. , Field Melvin , Lovell Mark R. , Iverson Grant , Johnston Karen M. , Maroon Joseph , Fu Freddie H.
Published: July 2017

Background:

The relevance of headache to outcome after sports-related concussion is poorly understood.

Hypotheses:

High school athletes reporting headache approximately 1 week after injury will have significantly more other concussion symptoms and will perform more poorly on neuropsychological tests than athletes not experiencing headache.

Study Design:

Prospective cohort study.

Methods:

Study participants included 109 high school athletes who had sustained concussion and who were divided into two groups: those reporting headache 7 days after injury and those reporting no headaches. The two groups were compared regarding on-field markers of concussion severity at the time of injury and symptoms and neurocognitive test results collected via ImPACT, a computerized neuropsychological test battery and postconcussion symptom scale, at a mean of 6.8 days after injury.

Results:

Athletes reporting posttraumatic headache demonstrated significantly worse performance on reaction time and memory ImPACT neurocognitive composite scores. These athletes also reported significantly more symptoms other than headache and were more likely to have demonstrated on-field anterograde amnesia.

Conclusions:

Findings suggest that any degree of postconcussion headache in high school athletes 7 days after injury is likely associated with an incomplete recovery after concussion.
Anterior Drawer Test for Acute Anterior Talofibular Ligament Injuries of the Ankle: How Much Load Should be Applied during the Test?
Authors: Tohyama Harukazu , Yasuda Kazunori , Ohkoshi Yasumitu , Beynnon Bruce D. , Renstrom Per A.
Published: July 2017

Background:

There is a lack of consensus regarding the magnitude of load for performing the anterior drawer test in evaluating acute ankle injuries.

Purpose:

To determine how much load should be applied during the anterior drawer test to detect the integrity of the anterior talofibular ligament.

Methods:

First, the anterior-posterior load-displacement response of nine cadaveric ankles was measured. Second, anterior displacement of the ankle was measured at 30 and 60 N of anterior load in 14 patients with acute tears of the anterior talofibular ligament.

Results:

In the cadaver study, the increased displacement by sectioning of the ligament measured at 10, 20, 30, and 40 N of anterior load were significantly greater than those measured at 60 N. In vivo examination of the subjects without anesthesia demonstrated that the injured-to-normal displacement value at 30 N of anterior load was significantly greater than the value at 60 N.

Conclusions:

This study suggests that a large magnitude of anterior load is not necessary to detect the integrity of the ligament during the anterior drawer test.

Clinical Relevance:

When evaluating the integrity of the anterior talofibular ligament in cases of acute ankle ligament injury, a relatively low-magnitude load should be applied.
Anteromedial Capsular Redundancy and Labral Deficiency in Shoulder Instability
Authors: Ahmad Christopher S. , Freehill Michael Q. , Blaine Theodore A. , Levine William N. , Bigliani Louis U.
Published: July 2017

Background:

Redundancy of the anteromedial capsule of the shoulder may persist despite proper tensioning of the capsule and repair of a Bankart lesion during an anteroinferior capsular shift procedure.

Hypothesis:

A barrel-stitch suture technique incorporated into a capsular shift procedure is effective in achieving satisfactory shoulder stability.

Study Design:

Uncontrolled retrospective review.

Methods:

A barrel-stitch technique was used for patients identified as having anteromedial capsular redundancy during a capsular shift procedure for anteroinferior instability.

Results:

The incidence of anteromedial capsular redundancy and labral deficiency was 49% (38 of 78). Patients with anteromedial capsular redundancy had a significantly greater number of dislocations before surgery (16.1 ± 21.3 versus 7.4 ± 7.4) and a greater duration of symptoms (79.8 ± 84.2 versus 31.6 ± 32.2 months). The mean postoperative Rowe score of patients with anteromedial capsular redundancy was 88.7 ± 14.8, with 92% having excellent or good results, compared with 88.9 ± 14.8 in the remaining patients and 93% excellent or good results.

Conclusions:

Anteromedial capsular redundancy is associated with longer preoperative duration of symptoms and more dislocations, but effective treatment can be achieved with a capsular shift procedure augmented with medial capsular imbrication with a barrel stitch.
A Review of the Special Tests Associated with Shoulder Examination: Part II: Laxity, Instability, and Superior Labral Anterior and Posterior (SLAP) Lesions
Authors: Tennent T. Duncan , Beach William R. , Meyers John F.
Published: July 2017

This is the second of a two-part article describing the various tests that have been used to examine the shoulder to find and treat problems in that area. Part I of this article (January/February 2003, pages 154—160) focused on tests used to examine rotator cuff abnormalities. This article attempts to clarify the tests of laxity, instability, and the superior labral anterior and posterior (SLAP) lesions 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.
Current Concepts in Arthroscopic Rotator Cuff Repair
Authors: Lo Ian K. Y. , Burkhart Stephen S.
Published: July 2017

The interest in arthroscopic rotator cuff repair has increased exponentially over the last 5 years. Although the operative technique of repair continues to evolve, there are now several studies reporting excellent results after arthroscopic repair of rotator cuff tears. In this review, we focus on new concepts and techniques related to arthroscopic rotator cuff repair that have been recently introduced.
The Effects of Radiofrequency Energy Treatment on Chondrocytes and Matrix of Fibrillated Articular Cartilage
Authors: Ryan Anne , Bertone Alicia L. , Kaeding Christopher C. , Backstrom Kristin C. , Weisbrode Steven E.
Published: July 2017

Background

There is no consensus regarding the safety of radiofrequency energy treatment for chondroplasty.

Hypothesis

Use of a radiofrequency thermal probe will produce a dose-dependent detrimental effect on chondrocytes in a setting mimicking the arthroscopic procedure.

Study Design

Controlled laboratory study.

Methods

Paired patellae from 11 horses were fibrillated; one served as the control while the contralateral patella was treated with 20, 40, and 60 watts of radiofrequency energy for 4 minutes. Proteoglycan synthesis, proteoglycan degradation, and cell viability were measured. Explant histologic sections were scored for cellular characteristics, metachromatic matrix staining intensity, and tissue architecture and were quantitatively analyzed for cell death.

Results

Mean peak surface articular cartilage temperatures were 35.47°C (20 watts), 40.76°C (40 watts), and 44.81°C (60 watts). Treatment at all three settings significantly decreased proteoglycan synthesis of the chondrocytes. Proteoglycan degradation increased with increased power setting. Treatment at 40 and 60 watts significantly decreased cell viability to 81% and 73%, respectively. Significant histologic changes occurred in the superficial cartilage zone with 60-watt application.

Conclusion

Use of radiofrequency energy on mechanically fibrillated articular cartilage induced a dose-dependent detrimental effect on chondrocytes and matrix metabolism.

Clinical Relevance

Cautious use of radiofrequency energy for treatment of articular cartilage is recommended until long-term effects are evaluated.
Allograft Transplantation in the Knee: Tissue Regulation, Procurement, Processing, and Sterilization
Authors: Vangsness C. Thomas , Garcia Ivan A. , Mills C. Randal , Kainer Marion A. , Roberts Michael R. , Moore Tillman M.
Published: July 2017

Use of musculoskeletal allografts has become increasingly popular, with widespread use among knee surgeons. The advantages and disadvantages of their use have been documented. In the knee, allografts are used for ligament reconstruction, meniscal transplantation, and articular surface reconstruction. The purpose of this review is to present issues surrounding the allograft industry, including regulation of tissues and tissue banks and procurement, processing, sterilization, and storage of allograft tissue. Tissue bank regulation is ultimately under the jurisdiction and authority of the Food and Drug Administration; some individual states regulate tissue banks. The American Association of Tissue Banks is a scientific organization that encourages education, research, and voluntary accreditation of tissue banks. It promotes safety and standards for retrieval, processing, storage, and distribution of transplantable human tissue. Allograft tissues are generally harvested and processed aseptically, which may not prevent contamination. Tissue sterilization is difficult and controversial. Tissue banks historically have used one of two methods of sterilization, ethylene oxide or gamma radiation. Both methods have risks and benefits. Newer methods of sterilization are being developed. Allograft tissue that is not transplanted fresh can be freeze-dried or deep frozen for storage. Ultimately, allograft transplantation in the knee facilitates knee form and function and enhances the patient's quality of life. Orthopaedic surgeons who use allograft tissue must understand the tissue banking process to provide safe and effective tissues to their patients.
Risk Factors Associated with Noncontact Injury of the Anterior Cruciate Ligament
Authors: Uhorchak John M. , Scoville Charles R. , Williams Glenn N. , Arciero Robert A. , Pierre Patrick St. , Taylor Dean C.
Published: July 2017

Background: The causes of noncontact anterior cruciate ligament injury remain an enigma.

Purpose: To prospectively evaluate risk factors for noncontact anterior cruciate ligament injuries in a large population of young athletic people.

Study Design: Prospective cohort study.

Methods: In 1995, 1198 new United States Military Academy cadets underwent detailed testing and many parameters were documented. During their 4-year tenure, all anterior cruciate ligament injuries that occurred were identified. Statistical analyses were used to identify the factors that may have predisposed the cadets to noncontact anterior cruciate ligament injuries.

Results: Among the 895 cadets who completed the entire 4-year study, there were 24 noncontact anterior cruciate ligament tears (16 in men, 8 in women). Significant risk factors included small femoral notch width, generalized joint laxity, and, in women, higher than normal body mass index and KT-2000 arthrometer values that were 1 standard deviation or more above the mean. The presence of more than one of these risk factors greatly increased the relative risk of injury. All female cadets who had some combination of risk factors sustained noncontact anterior cruciate ligament injuries, indicating that some combinations of factors are especially perilous to the female knee.

Conclusion: Several risk factors may predispose young athletes to noncontact anterior cruciate ligament injury.
Measurement of Posterior Tibial Translation in the Posterior Cruciate Ligament-Reconstructed Knee
Authors: Ma C. Benjamin , Kanamori Akihiro , Vogrin Tracy M. , Woo Savio L-Y. , Harner Christopher D.
Published: July 2017

Background: The measurement of anterior or posterior tibial translation depends on the existence of a repeatable and accurate reference position of the knee from which the corresponding translation is measured.

Hypothesis: Clinical measurements of posterior tibial translation alone do not accurately reflect the laxity of posterior cruciate ligament-reconstructed knees.

Study Design: Controlled laboratory study.

Methods: Ten human cadaveric knees were tested by using a robotic/universal force-moment sensor testing system. The reference positions and the resulting kinematics in response to a 134-N anterior-posterior tibial load were determined for the intact and reconstructed knees. Posterior cruciate ligament reconstruction was performed with the graft tensioned and fixed at two different positions: 1) 90° of knee flexion with a 134-N anterior tibial load and 2) full extension with no load.

Results: Posterior cruciate ligament reconstruction with graft fixation at full extension with no load resulted in anterior shift of the reference position by 1.5 to 3.2 mm. The reconstruction resulted in an overconstrained knee with significantly decreased total anterior-posterior translation of 2.6 to 3.2 mm. However, the posterior tibial translation measured was not significantly different from that of the intact knee. Posterior cruciate ligament reconstruction with graft fixation performed at 90° of flexion with a 134-N anterior tibial load resulted in kinematics similar to those of the intact knee.

Conclusion: Posterior tibial translations that are measured clinically can be misleading because the reference position of the knee can be shifted significantly after posterior cruciate ligament reconstruction.

Clinical Relevance: The measurement of total anterior-posterior translation may be a more accurate way to assess kinematics of the reconstructed knee.
Biomechanical Evaluation of a New Technique for Rotator Cuff Repair
Authors: Petit Charles J. , Boswell Robert , Mahar Andrew , Tasto James , Pedowitz Robert A.
Published: July 2017

Background: In recent studies, investigators have used a cyclic loading model to investigate the efficacy of rotator cuff fixation modalities.

Hypothesis: A bioabsorbable poly-D-lactic acid screw and toothed washer implant will provide more stable fixation of rotator cuff repairs than standard suture anchor techniques.

Study Design: Controlled laboratory study.

Methods: Forty bovine shoulders (ages 3 to 6 months) had 1 × 2 cm defects created in the infraspinatus tendon. There were five repair groups (eight specimens per group) consisting of either two screw and washer implants or two suture anchors. Four suture techniques were tested: single-loaded anchors with simple sutures, double-loaded anchors with simple sutures, single-loaded anchors with horizontal mattress sutures, or single-loaded anchors with modified Mason-Allen sutures. Repairs were loaded at 5-second cycles from 10 to 180 N with use of a hydraulic testing machine. The number of cycles to gap formation of 5 and 10 mm was recorded.

Results: Gap formation of 5 and 10 mm occurred significantly later for the screw repair group than for any of the suture anchor groups. There was no significant difference between suture groups.

Conclusions: The bioabsorbable screw and washer provided more stable fixation than suture anchor techniques under isometric cyclic loading conditions.

Clinical Relevance: This is a time-zero study of implant performance. The results indicate that the implant may decrease clinical failures in the early postoperative period under standard rehabilitation protocols.
Physeal-Sparing Intraarticular Anterior Cruciate Ligament Reconstruction in Preadolescents
Authors: Guzzanti Vincenzo , Falciglia Francesco , Stanitski Carl L.
Published: July 2017

Background: In the very young patient in need of anterior cruciate ligament reconstruction, the option of reconstruction with physeal-sparing techniques is valid because it is not known what percentage of physeal transgression causes adverse growth consequences.

Purpose: To report our experience with an intraarticular technique for anterior cruciate ligament reconstruction that spares the open femoral and tibial physes yet allows soft tissue graft fixation in the femoral and tibial tunnels.

Methods: Eight preadolescents underwent physeal-sparing intraarticular reconstruction for anterior cruciate ligament insufficiency with the use of semitendinosus and gracilis tendon grafts. All eight patients were in Tanner stage 1 with an average chronologic age of 11.15 years and average bone age of 10.9 years. Preoperative prediction of lower limb growth averaged 10.8 cm.

Results: Five of the eight patients had reached skeletal maturity at follow-up, which was at an average of 69.2 months postoperatively. For these five, the Orthopadische Arbeitsgruppe Knie (OAK) score averaged 97 and the average KT-2000 arthrometer difference was 1.8 mm. Average growth in total height from surgery to final follow-up was 21.7 cm. No patient had a leg-length discrepancy or angular deformity, as verified by clinical or teleroentgenogram measurements.

Conclusions: The technique presented in this study provided graft isometry and stability without adverse physeal consequences. Additional research is needed to determine the threshold percentage of physeal transgression for avoiding growth disturbances in humans.
Clinical, Functional, and Radiologic Outcome in Team Handball Players 6 to 11 Years after Anterior Cruciate Ligament Injury
Authors: Myklebust Grethe , Holm Inger , Mæhlum Sverre , Engebretsen Lars , Bahr Roald
Published: July 2017

Background

Long-term outcome after anterior cruciate ligament injury among top-level pivoting athletes is unknown.

Purpose

To evaluate outcome among competitive team handball players after anterior cruciate ligament injury.

Study Design

Prospective cohort study.

Methods

A previously studied group of 86 elite players who had an anterior cruciate ligament rupture were invited to participate in follow-up evaluations a mean of 7.8 years later.

Results

Among the 57 operatively treated patients who returned for follow-up, 33 (58%) returned to team handball at their preinjury level, compared with 18 of 22 (82%) in the nonoperative group. Eleven of the 50 players (22%) who continued playing reinjured their anterior cruciate ligament when playing team handball. The overall Lysholm score was 85 ± 13 in both groups, but the five players classified as poor were all operatively treated. Nearly half of the players had an International Knee Documentation Committee classification of abnormal or severely abnormal. There were significant differences between the injured and uninjured leg in functional (2.5% to 8%), strength (3.8% to 10.1%), and KT-1000 arthrometer tests (27%). In the operatively treated group, 11 developed radiologic gonarthrosis, compared with 6 in the nonoperatively treated group. There was no correlation between radiologic findings and pain scores.

Conclusion

A more restrictive attitude regarding return to competitive pivoting sports after anterior cruciate ligament injury may be warranted.
Effects of Nonsteroidal Antiinflammatory Medication on Satellite Cell Proliferation During Muscle Regeneration
Authors: Thorsson Ola , Rantanen Jussi , Hurme Timo , Kalimo Hannu
Published: July 2017

Previous experimental studies have indicated delayed muscle regeneration after nonsteroidal antiinflammatory drug therapy. Successful regeneration of muscle after injury requires activation of normally dormant satellite cells that share the basal laminae with adjacent muscle cells. In the presence of adequate capillary ingrowth, satellite cells proliferate into myotubes and eventually form new muscle cells. In this study, the onset and extent of satellite cell and fibroblast proliferation as well as the production of myotubes and capillaries were analyzed with immunohistochemical methods after contusion injuries to rats' gastrocnemius muscles. Two groups of animals received daily doses of an intramuscular nonsteroidal antiinflammatory drug (naproxen) starting 6 hours and 3 days after injury, respectively. Treated animals were compared with similarly injured untreated animals. Satellite cell and fibroblast proliferation were unaffected by the treatment, and there were no significant differences in myotube or capillary production between treated and control animals. We conclude that naproxen treatment does not compromise the basic process of myofiber regeneration after injury.
The Clinical Diagnosis of Subcutaneous Tear of the Achilles Tendon
Authors: Maffulli Nicola
Published: July 2017

A study to determine the sensitivity, specificity, and positive and negative predictive values of several clinical diagnostic tests of subcutaneous Achilles tendon rupture was performed during a 13-year period. There were 174 patients with clinical diagnosis of unilateral complete subcutaneous Achilles tendon tear and 28 patients with unilateral suspected but no actual Achilles tendon tear. The following tests were used: palpation, calf squeeze, Matles, Copeland, and O'Brien. Palpation of the gap was the least sensitive clinical test with the patient awake (0.73), increasing to 0.81 when the test was performed under anesthesia; the Copeland and O'Brien tests showed a sensitivity of 0.8. Both the calf squeeze and Matles tests were significantly more sensitive than the other tests (0.96 and 0.88, respectively; 0.022 P 0.05). All tests showed a high positive predictive value, with no statistically significant difference between the various tests. In the 28 patients with no evidence of a subcutaneous Achilles tendon tear on imaging, the tests showed a high capability to detect that the Achilles tendon was intact (gap palpation specificity, 0.89; calf squeeze test specificity, 0.93; Matles test specificity, 0.85). Whichever tests were performed, at least two of them were positive for a subcutaneous tear of the Achilles tendon in all patients in this study.
Meniscal Repair in the Goat Model
Authors: Ritchie Joseph R. , Miller Mark D. , Bents Robert T. , Smith Douglas K.
Published: July 2017

We evaluated the effect of adjunctive healing measures on central tears of the adult goat medial meniscus and the role of magnetic resonance arthrography in the assessment of menisci that have undergone a repair. Peripheral tears were made unilaterally in the medial menisci of seven goats in Group I and repaired with nonabsorbable suture. Six Group II goats had central medial meniscal tears repaired as in Group I plus an exogenous fibrin clot. Eight Group III goats had central tears plus abrasion of the parameniscal synovium and tear edges. Six months after surgery, a magnetic resonance imaging scan and a magnetic resonance arthrogram were obtained and the menisci were examined grossly. Group I goats showed healing in all seven knees. Central tears repaired with a fibrin clot (Group II) showed healing in one of six knees (17%). Central tears repaired with abrasion (Group III) showed healing in seven of eight knees (87.5%). Magnetic resonance arthrography was 100% accurate in detecting the presence or absence of complete residual tears. This study supports the current trend of using adjunctive measures for repair of central tears. Furthermore, abrasion of the parameniscal synovium and the tear edges appears to be more effective than the use of an exogenous fibrin clot. Magnetic resonance arthrography is useful in the evaluation of menisci that have undergone repair.
Hyperbaric Oxygen in the Treatment of Acute Muscle Stretch Injuries
Authors: Best Thomas M. , Loitz-Ramage Barbara , Corr David T. , Vanderby Ray
Published: July 2017

Hyperbaric oxygen therapy is an established therapy in several areas of clinical medicine. However, studies have produced conflicting results regarding its efficacy for sports-related soft tissue injuries. This study examines the use of hyperbaric oxygen therapy after an acute muscle stretch injury in an animal model. Two groups of rabbits (nine in each group) were subjected to a partial stretch injury to the tibialis anterior muscle-tendon unit. For all 18 animals, the injuries were induced in the left limb, and the uninjured right limb served as a sham-operated control. In group 1, the animals were exposed to hyperbaric oxygen ( 95% O2 at 2.5 atm) for 60 minutes daily for 5 days. Treatment began 24 hours after injury. Group 2 animals were not exposed to hyperbaric oxygen. Evaluation 7 days after injury demonstrated a functional deficit (percent ankle isometric torque; injured side versus uninjured side) of 14.9% 5.5% (mean SD) for the treated group and 47.5% 5.4% for the untreated group, representing a statistical difference using the Behrens-Fisher version of the t test (P 0.001). Morphologic studies revealed more complete healing in the treated group. This study suggests that hyperbaric oxygen therapy may play a role in accelerating recovery after acute muscle stretch injury. Further studies are needed before definitive conclusions and treatment recommendations can be made.
Significance of the Single-Legged Hop Test to the Anterior Cruciate Ligament-Reconstructed Knee in Relation to Muscle Strength and Anterior Laxity
Authors: Sekiya Ichiro , Muneta Takeshi , Ogiuchi Takashi , Yagishita Kazuyoshi , Yamamoto Haruyasu
Published: July 2017

We investigated the significance of the single-legged hop test to the anterior cruciate ligament-reconstructed knee as it specifically relates to knee muscle strength recovery and residual anterior laxity. The hop test was conducted on 107 patients with unilateral anterior cruciate ligament-reconstructed knees (78 semitendinosus tendon autografts and 29 bone-patellar tendon-bone autografts). Patients were tested an average of 2 years after surgery. Correlation coefficient analyses determined whether the relationship between knee muscle strength recovery and the hop test was invariant across all levels of residual anterior laxity and whether the relationship between residual anterior laxity and the hop test was invariant across levels of quadriceps muscle strength recovery. Furthermore, we examined the effect of graft harvest site on the hop index. Positive correlations were found between the hop index and muscle strength index at all levels of residual anterior laxity (P 0.05), but these correlation coefficients were relatively low. There were no apparent correlations between the hop index and residual anterior laxity at all levels of quadriceps muscle strength recovery. There was no significant difference in the average hop index between the semitendinosus tendon autograft group and the bone-patellar tendon-bone autograft group.
Isolated Sectioning of the Medial and Posteromedial Capsular Ligaments in the Posterior Cruciate Ligament-Deficient Knee
Authors: Ritchie Joseph R. , Bergfeld John A. , Kambic Helen , Manning Timothy
Published: July 2017

This study was undertaken to determine the contribution of various structures in the posterior cruciate ligament-deficient knee in resisting posterior tibial translation. With “isolated” injuries to the posterior cruciate ligament, the amount of posterior translation will decrease with the posterior drawer test as the knee is taken from neutral to internal tibial rotation. The present study was performed to conclusively determine the anatomic structure responsible for this clinical observation. The TestStar device was used to perform single-plane posterior drawer tests in 14 cadaveric knee specimens. The tests were performed with the knee in neutral tibial rotation and in 20° of internal tibial rotation. The intact knee was tested and then the knee was tested after sequential sectioning of the meniscofemoral ligaments, the posterior cruciate ligament, the posteromedial capsule, and the superficial medial collateral ligament. With the knee in neutral rotation, posterior translation continued to increase as each structure was sectioned. With the knee in internal tibial rotation, posterior displacement was significantly less than in neutral rotation for each state until the superficial medial collateral ligament was sectioned; posterior translation was increased after its sectioning. Our data demonstrate that the superficial medial collateral ligament is the structure responsible for a decrease in posterior tibial translation in the posterior cruciate ligament-deficient knee.
Evaluation and Treatment of Posterior Cruciate Ligament Injuries
Authors: Harner Christopher D. , Höher Jürgen
Published: July 2017

Improved basic science data on the anatomy and bio-mechanics of the human posterior cruciate ligament have provided the orthopaedic surgeon with new information on which to base treatment decisions. Injuries to the posterior cruciate ligament are reported to comprise approximately 3% of all knee ligament injuries in the general population and as high as 37% in an emergency department setting. While the diagnosis of a posterior cruciate ligament injury can often be made with a physical examination, ancillary studies such as radiographs and magnetic resonance images can be very helpful in detecting associated ligament and bony injuries. In general, most partial (grades I and II) posterior cruciate ligament injuries can be treated nonoperatively. However, surgical reconstruction is usually recommended for those posterior cruciate ligament injuries that occur in combination with other structures. In this review, current surgical techniques of posterior cruciate ligament reconstruction based on anatomic and biomechanical studies will be discussed.
Sports Injuries in Team Handball
Authors: Seil Romain , Rupp Stefan , Tempelhof Siegbert , Kohn Dieter
Published: July 2017

One hundred eighty-six players of 16 teams in 2 male team handball senior divisions were observed prospectively for 1 season to study the injury incidence in relation to exposure in games and practices. Ninety-one injuries were recorded. Injury incidence was evaluated at 2.5 injuries per 1000 player-hours, with a significantly higher incidence in game injuries (14.3 injuries per 1000 game-hours) compared with practice injuries (0.6 injuries per 1000 practice-hours). Practice injury incidence was higher in the lower performance level group, and game injury incidence was higher in the high-level group. The upper extremity was involved in 37% of the injuries, and the lower extremity in 54%. The knee was the most commonly injured joint, followed by the finger, ankle, and shoulder. Knee injuries were the most severe injuries, and they were more frequent in high-level players. There was an increase in the severity of injury with respect to performance level. The injury mechanism revealed a high number of offensive injuries, one-third of them occurring during a counterattack. The injury pattern showed certain variations with respect to player position and performance level. Prophylactic equipment was used by a majority of players at the higher performance level.
Posterior Labral Injury in Contact Athletes
Authors: Mair Scott D. , Zarzour Robert “Hap” , Speer Kevin P.
Published: July 2017

Nine athletes (seven football offensive linemen, one defensive lineman, and one lacrosse player) were found at arthroscopy to have posterior labral detachment from the glenoid. In our series, this lesion is specific to contact athletes who engage their opponents with arms in front of the body. All patients had pain with bench pressing and while participating in their sport, diminishing their ability to play effectively. Conservative measures were ineffective in relieving their symptoms. Examination under anesthesia revealed symmetric glenohumeral translation bilaterally, without evidence of posterior instability. Treatment consisted of glenoid rim abradement and posterior labral repair with a bioabsorbable tack. All patients returned to complete at least one full season of contact sports and weightlifting without pain (minimum follow-up, 2 years). Although many injuries leading to subluxation of the glenohumeral joint occur when an unanticipated force is applied, contact athletes ready their shoulder muscles in anticipation of impact with opponents. This leads to a compressive force at the glenohumeral joint. We hypothesize that, in combination with a posteriorly directed force at impact, the resultant vector is a shearing force to the posterior labrum and articular surface. Repeated exposure leads to posterior labral detachment without capsular injury. Posterior labral reattachment provides consistently good results, allowing the athlete to return to competition.
Multiplanar Analysis of Acromion Morphology
Authors: MacGillivray John D. , Fealy Stephen , Potter Hollis G. , O'Brien Stephen J.
Published: July 2017

To more completely describe acromion morphology and its relationship to impingement syndrome, we performed three-dimensional magnetic resonance imaging (N 111) or computed tomography (N 27) on 132 symptomatic shoulders. The mean patient age was 46.2 years (range, 14 to 86). Four parameters were evaluated: the angle of anterior slope of the acromion in the midsagittal and lateral-sagittal planes, lateral acromial angulation in the coronal plane, and the presence or absence of medial encroachment in the acromioclavicular joint. Twenty-five asymptomatic, age-matched shoulders were used as controls. All imaging data were combined because no significant differences existed between the two imaging techniques. The mean acromion angle was 19.4° in the midsagittal plane and 20° in the lateral-sagittal plane. In the coronal plane, 97 (73%) acromions were neutral and 35 (27%) were downward sloping. Medial encroachment was present in 31 (24%) shoulders. Age distribution from the 2nd to 8th decade demonstrated a consistent and gradual transition from a flat acromion in the younger decades to a more hooked acromion in the older decades that was significant in both the midsagittal and lateral-sagittal planes. Furthermore, a greater percentage of patients were found to have downward angulating acromions with increasing age. Ninety-eight patients (74%) had stage II or III impingement. Of these shoulders, 39 (40%) had type I acromions, 51 (52%) type II, and 8 (8%) type III. Twenty-eight of 33 acromions with coronal lateral downward sloping had impingement, and all 31 shoulders with medial encroachment had impingement.
Sagittal Plane Translation of the Knee During Stair Walking
Authors: Vergis Anil , Gillquist Jan
Published: July 2017

With an electrogoniometer system, we made bilateral measurements of the maximal sagittal plane anterior-posterior knee translations in 15 healthy subjects (controls) and 14 patients with arthroscopically confirmed unilateral anterior cruciate ligament deficiency during two types of ascents and descents (straight and side). In both groups, during the ascent cycle the tibia moved anteriorly in relation to the femur, whereas during the descent cycle it moved posteriorly. There was wide individual variation in maximal translation in both the control and anterior cruciate ligament-deficient groups (range, 1 to 12 mm; mean, 7 mm). The maximal translations were similar in both groups (P 0.05), but they occurred at a significantly smaller flexion angle in the injured knees (38° 8°) than in the control and non-injured knees (44° 8°) (P 0.05). The translation during step ascent and descent did not differ between the injured and control knees. These findings indicate that patients with anterior cruciate ligament injuries are able to control abnormal anterior translation during normal activity.
Effects of Therapeutic Ultrasound on the Regeneration of Skeletal Myofibers After Experimental Muscle Injury
Authors: Rantanen Jussi , Thorsson Ola , Wollmer Per , Hurme Timo , Kalimo Hannu
Published: July 2017

Therapeutic ultrasound is used by many in the treatment of muscle injuries, but no previous attempts to objectively assess its effects on regenerating skeletal myofibers have been published. In this descriptive study, we followed the regeneration of contusion injury to the rat gastrocnemius muscle during treatment with pulsed ultrasound. The speed of myoregeneration in ultrasound-treated animals was compared with that in control animals by immunohistochemical, morphometric, and scintigraphic analyses. Although satellite cell proliferation was enhanced significantly (up to 96%) by the ultrasound treatment during the early stages of regeneration, there was no such effect on myotube production. The period of rapid fibroblast proliferation was extended from 3 to 4 days in the control group to 7 to 10 days in the ultrasound therapy groups, whereas recapillarization was virtually unaffected. We conclude that although treatment with pulsed ultrasound can promote the satellite cell proliferation phase of the myoregeneration, it does not seem to have significant effects on the overall morphological manifestations of muscle regeneration.
Tennis After Total Hip Arthroplasty
Authors: Mont Michael A. , LaPorte Dawn M. , Mullick Tarun , Silberstein Charles E. , Hungerford David S.
Published: July 2017

The purpose of this study was to characterize patients who play tennis after undergoing hip arthroplasty in terms of their functional abilities and degree of satisfaction. A questionnaire was sent to all United States Tennis Association member associations in a tri-state area to identify players who had undergone a hip arthroplasty. The study group had 50 men and 8 women with a mean age of 70 years (range, 47 to 89). Only 14% of the patients' surgeons approved this tennis activity, with 34% of the surgeons recommending only doubles. Three patients required revision surgery after a mean of 8 years. One year after arthroplasty, players played both singles and doubles approximately three times per week. All tennis players were extremely satisfied with their hip arthroplasties and their increased ability to participate in their favorite sport. Because this study was confined to association members, further studies are needed to assess the general effect of tennis on total hip arthroplasty. Until future studies are performed, the authors would recommend that physicians advise caution in tennis activities and to carefully follow their patients yearly to see if osteolysis is occurring prematurely.
The Effect of Anterior Cruciate Ligament Trauma and Bracing on Knee Proprioception
Authors: Beynnon Bruce D. , Ryder Steven H. , Konradsen Lars , Johnson Robert J. , Johnson Kelly , Renström A.
Published: July 2017

We studied the effect that chronic anterior cruciate ligament disruption, functional bracing, and a neoprene sleeve have on knee proprioception by measuring the threshold to detection of passive knee motion in all three conditions. The threshold to detection of passive knee motion was worse in knees with chronic anterior cruciate ligament insufficiency when compared with uninjured knees. This difference was small, on average an additional 0.28° of flexion-extension rotation was required for the anterior cruciate ligament-deficient knee before the subject detected motion, and of questionable significance from a clinical and functional perspective. Wearing a functional brace or neoprene sleeve on the anterior cruciate ligament-deficient knee did not significantly change the threshold to detection of passive motion in comparison with the same knee without a brace, although improvements were observed. There was no relationship between the most common clinical means of characterizing altered bio-mechanics of the anterior cruciate ligament-deficient knee (that is, the magnitude of anterior-posterior knee laxity and the grade of pivot shift) and the threshold to detection of passive knee motion.
Histologic Evaluation of the Glenohumeral Joint Capsule After the Laser-Assisted Capsular Shift Procedure for Glenohumeral Instability
Authors: Hayashi Kei , Massa Kathleen L. , Thabit George , Fanton Gary S. , Dillingham Michael F. , Gilchrist Kennedy W. , Markel Mark D.
Published: July 2017

Glenohumeral joint capsule obtained from 42 patients who had undergone an arthroscopic laser-assisted capsular shift procedure was evaluated histologically. A total of 53 samples from the anterior inferior glenohumeral ligament of the joint capsule were collected before and at various times after the procedure (range, 0 to 38 months). Despite glenohumeral instability, joint capsule of the patients before the procedure showed no significant histologic lesions. Laser treatment significantly altered the histologic properties of the tissue as evidenced by hyalinization of collagen and necrotic cells (time 0). Tissues sampled during the short-term period (3 to 6 months) after the procedure demonstrated fibrous connective tissue with reactive cells and vasculature. Collagen and cell morphology returned to normal in the middle- to long-term period (7 to 38 months) after the procedure, while the number of fibroblasts remained elevated. Joint capsule collected from the shoulders of six patients who experienced stiffness after the procedure showed persistent synovial, cellular, and vascular reaction even after 1 year postoperatively, the cause of which is unclear. This study re-
Surgical Treatment for Chronic Lower-Leg Compartment Syndrome in Young Female Athletes
Authors: Micheli Lyle J. , Solomon Ruth , Solomon John , Plasschaert Véronique F. P. , Mitchell Robert
Published: July 2017

Our experience in treating chronic lower-leg compartment syndrome suggests that women may be more susceptible to this injury than are men, an observation for which there is support in the literature. Furthermore, when we evaluated the 47 young female athletes (age range, 13 years 11 months to 21 years 10 months) from our practice on whom 78 separate surgeries were performed, we found a lower success rate than those generally reported in studies that combine male and female patients. We suspect, therefore, that for reasons as yet unclear, women may also respond less well than men to operative fasciotomy.
Noncontrast Magnetic Resonance Imaging of Superior Labral Lesions
Authors: Connell David A. , Potter Hollis G. , Wickiewicz Thomas L. , Altchek David W. , Warren Russell F.
Published: July 2017

Previous studies report that noncontrast magnetic resonance imaging is limited in the evaluation of the superior glenoid labrum. From our magnetic resonance imaging database of 2552 patients, we prospectively identified 104 patients with superior labral lesions who subsequently went on to arthroscopic surgery. Magnetic resonance images were assessed to identify fraying, flap tears, bucket-handle tears, or displaced flap of fibrocartilage. The biceps tendon was also evaluated. Patients were categorized according to Snyder's classification, and the findings on the magnetic resonance images were correlated with surgical findings. One hundred of the 104 tears suspected on the images were confirmed at surgery. There were four false-positives and two false-negatives, the former reflecting one normal labrum, two meniscoid-type labra, and one sublabral foramen. With arthroscopic surgery as the standard, magnetic resonance imaging had a sensitivity of 98.0% (100 of 102), a specificity of 89.5% (34 of 38), and an accuracy of 95.7% (134 of 140) for detection of superior labral lesions. We concluded that high-resolution noncontrast magnetic resonance imaging can accurately diagnose superior labral lesions and aid in surgical management.