Search

Background: Anterolateral complex injuries are becoming more recognized. While these are known to affect tibiofemoral mechanics, it is not known how they affect patellofemoral joint behavior. Purpose: To determine the effect of (1) sectioning the anterolateral complex and (2) performing a MacIntosh tenodesis under various conditions on patellofemoral contact mechanics and kinematics. Study Design: Controlled laboratory study. Methods: Eight fresh-frozen cadaveric knees were tested in a customized rig, with the femur fixed and tibia free to move, with optical tracking to record patellar kinematics and with thin pressure sensors to record patellofemoral contact pressures at 0°, 30°, 60°, and 90° of knee flexion. The quadriceps and iliotibial tract were loaded with 205 N throughout testing. Intact and anterolateral complex–sectioned states were tested, followed by 4 randomized tenodeses applying 20- and 80-N graft tension, each with the tibia in its neutral intact alignment or left free to rotate. Statistical analyses were undertaken with repeated measures analysis of variance, Bonferroni post hoc analysis, and paired samples t tests. Results: Patellar kinematics and contact pressures were not significantly altered after sectioning of the anterolateral complex (all: P > .05). Similarly, they were not significantly different from the intact knee in tenodeses performed when fixed tibial rotation was combined with 20- or 80-N graft tension (all: P > .05). However, grafts tensioned with 20 N and 80 N while the tibia was free hanging resulted in significant increases in lateral patellar tilt (P < .05), and significantly elevated lateral peak patellofemoral pressures (P < .05) were observed for 80 N. Conclusion: This work did not find that an anterolateral injury altered patellofemoral mechanics or kinematics, but adding a lateral tenodesis can elevate lateral contact pressures and induce lateral patellar tilting if the tibia is pulled into external rotation by the tenodesis. Although these in vitro changes were small and might not be relevant in a fully loaded knee, controlling the position of the tibia at graft fixation is effective in avoiding overconstraint at time zero in a lateral tenodesis. Clinical Relevance: Small changes in lateral patellar tilt and patellofemoral contact pressures were found at time zero with a MacIntosh tenodesis. These changes were eliminated when the tibia was held in neutral rotation at the time of graft fixation. The risk of overconstraint after a lateral tenodesis therefore seems low and in accordance with recent published reports. [ABSTRACT FROM AUTHOR]

Background: The plantaris tendon (PT) has been thought to contribute to symptoms in a proportion of patients with Achilles midportion tendinopathy, with symptoms improving after PT excision. Hypothesis: There is compression and differential movement between the PT and Achilles tendon (AT) during ankle plantarflexion and dorsiflexion. Study Design: Descriptive laboratory study. Methods: Eighteen fresh-frozen cadaveric ankles (mean ± SD age: 35 ± 7 years, range = 27-48 years; men, n = 9) were mounted in a customized testing rig, where the tibia was fixed but the forefoot could be moved freely. A Steinmann pin was drilled through the calcaneus, enabling a valgus torque to be applied. The soleus, gastrocnemius, and plantaris muscles were loaded with 63 N with a weighted pulley system. The test area was 40 to 80 mm above the os calcis, corresponding to where the injury is observed clinically. Medially, the AT and PT were exposed, and a calibrated flexible pressure sensor was inserted between the tendons. Pressure readings were recorded with the ankle in full dorsiflexion, full plantarflexion, and plantargrade and repeated in these positions with a 5 N·m torque, simulating increased hindfoot valgus. The pressure sensor was removed and the PT and AT marked with ink at the same level, with the foot held in neutral rotation and plantargrade. Videos and photographs were taken to assess differential motion between the tendons. After testing, specimens were dissected to identify the PT insertion. One-way analysis of variance and paired t tests were performed to make comparisons. Results: The PT tendons with an insertion separate from the AT demonstrated greater differential motion through range (14 ± 4 mm) when compared with those directly adherent to the AT (2 ± 2 mm) (P < .001). Mean pressure between the PT and AT rose in terminal plantarflexion for all specimens (P < .001) and was more pronounced with hindfoot valgus (P < .001). Conclusion: The PT inserting directly into the calcaneus resulted in significantly greater differential motion as compared with the AT. Tendon compression was elevated in terminal plantarflexion, suggesting that adapting rehabilitation tendon-loading programs to avoid this position may be beneficial. Clinical Relevance: The insertion pattern of the PT may be a factor in plantaris-related midportion Achilles tendinopathy. Terminal range plantarflexion and hindfoot valgus both increased AT and PT compression, suggesting that these should be avoided in this patient population. [ABSTRACT FROM AUTHOR]

Background: Patients with chronic exertional compartment syndrome (CECS) have pain during exercise that subsides with rest.Diagnosis is usually confirmed by intramuscular compartment pressure (IMCP) measurement. Controversy exists regarding theaccuracy of existing diagnostic criteria.Purpose: (1) To compare dynamic IMCP measurement and anthropometric factors between patients with CECS and asymptomaticcontrols and (2) to establish the diagnostic utility of dynamic IMCP measurement.Study Design: Cohort study (diagnosis); Level of evidence, 2.Methods: A total of 40 men aged 21 to 40 years were included in the study: 20 with symptoms of CECS of the anterior compartmentand 20 asymptomatic controls. Diagnoses other than CECS were excluded with rigorous inclusion criteria and magneticresonance imaging. The IMCP was measured continuously before, during, and after participants exercised on a treadmill, wearingidentical footwear and carrying a 15-kg load.Results: Pain experienced by study subjects increased incrementally as the study progressed (P\.001). Pain levels experiencedby the case group during each phase of the exercise were significantly different (P = .021). Subjects had higher IMCP immediatelyupon standing at rest compared with controls (23.8 mm Hg [controls] vs 35.5 mm Hg [subjects]; P = .006). This relationship persistedthroughout the exercise protocol, with the greatest difference corresponding to the period of maximal tolerable pain(68.7 mm Hg [controls] vs 114 mm Hg [subjects]; P \ .001). Sensitivity and specificity were consistently higher than the existingcriteria with improved diagnostic value (sensitivity = 63%, specificity = 95%; likelihood ratio = 12.5 [95% CI, 3.2-49]).Conclusion: Anterior compartment IMCP is elevated immediately upon standing at rest in subjects with CECS. In patients withsymptoms consistent with CECS, diagnostic utility of IMCP measurement is improved when measured continuously during exercise.A cutoff of 105 mm Hg in phase 2 provides better diagnostic accuracy than do the Pedowitz criteria of 30 mm Hg and20 mm Hg at 1 and 5 minutes after exercise, respectively. [ABSTRACT FROM AUTHOR]

The article presents a study on the adverse effects of progressive medialization and lateralization on patellofemoral joint (PFJ) kinematics, contact mechanics and stability. Topics covered include patellfemoral tracking, contact pressures, and tibial tuberosity-trochlear groove (TT-TG). Also mentioned is the use of an optical tracking system.

The article examines whether nonanatomic positioning of the tunnel or graft overtensioning during medial patellofemoral ligament (MPFL) reconstruction will adversely affect patellar tracking and patellofemoral joint contact mechanics. The study found that anatomically positioned reconstruction with 2-N tension fixed at 30 degrees or 60 degrees of knee flexion restored joint contact pressures and tracking. The importance of a correct femoral tunnel position and graft tensioning is also noted.

Background: Multiple percutaneous longitudinal tenotomies have been successfully undertaken in runners with isolated midportionAchilles tendinopathy (nodular lesions<2.5 cm) without any sign of paratendinopathy.Hypothesis: In the long term, minimally invasive multiple tenotomies allow the patient to remain involved in middle- and longdistancerunning. Clinical and ultrasound (US) evidence of paratendinopathy is a negative prognostic factor.Study Design: Case series study; Level of evidence, 4.Methods: A total of 39 patients were reviewed at an average follow-up of 17 years (range, 15-22 years) after US-guided multiplepercutaneous longitudinal tenotomies for chronic Achilles tendinopathy. The Victorian Institute of Sports Assessment–Achilles(VISA-A) questionnaire was completed by each patient, maximum calf circumference and isometric plantarflexion strength ofthe gastrocsoleus complex were measured in both the affected and contralateral legs, and functional assessment was scoredby the 4-point Boyden scale. Achilles tendon changes were also assessed according to the grayscale US grading system.Results: At the final follow-up, the maximum calf circumference and the strength in the operated leg were not significantly differentthan those measured preoperatively, but they were significantly lower than those on the contralateral side. This did notaffect patients’ daily or sports activities. All patients had returned to their preinjury working occupation; 20 patients were stillactive in middle- and long-distance running, with an average current level of sport and function that was 60% ± 13% comparedwith baseline status (before onset of symptoms). Thirty of 39 patients (77%) reported good or excellent outcomes according tothe Boyden assessment. On US assessment, the tendon was generally thicker than the contralateral asymptomatic tendon (average,7.0 vs 8.7 mm, respectively; P = .003). There was no significant difference (P > .05) when comparing patients with good orexcellent Boyden results versus those with fair or poor outcomes. The mean VISA-A score was 78.5, with no significant differencebetween patients with and without paratendinopathy on US assessment (P > .05). All of the patients who did not return to runningor who gave up sports activities had signs of paratendinopathy.Conclusion: This approach to the management of midportion Achilles tendinopathy is safe, has a low cost, and is effective in thelong term. [ABSTRACT FROM AUTHOR]

The article discusses the use of anterior talofibular ligament Broström repair for the management of chronic lateral ankle instability. It includes a study conducted on athletes who were assessed for their level of sport activity and the development of degenerative changes to the ankle. It concludes that combination of Broström repair and ankle arthroscopy allows athletes to return to their normal sports activities.

The article discusses the study conducted to measure effectiveness of chronic adductor enthesopathy. Study includes collection of radiographs and magnetic resonance imaging groin study protocol. Also included is the note of visual analog scale (VAS) pain score. It was concluded that selective partial adductor longus release provides excellent pain relief for chronic adductor enthesopathy in professional athletes.

The article presents the study of validation of a rotational measurement device (RMD) for measuring knee internal-external rotational laxity. The methods including dial test in the supine position, the measuring system and data validation are discussed. The study concluded the clinical RMD for measuring rotational laxity of the knee was portable, easy, and comfortable to use in the clinical setting.

The article discusses an investigation aimed to find out if the modified Harris Hip Score (mHHS) indicates patient satisfaction after hip arthroscopy. The results showed a correlation between patient satisfaction and the mHHS. Limitation of the mHHS as an outcome measure in the prediction of patient satisfaction was shown. Further investigation is required to assess factors beyond current standard orthopaedic clinical outcome measures that may affect patient satisfaction after hip arthroscopy.

The article assesses the potential of remplissage repair in prevention of recurrent shoulder instability. A survey was made on the patients suffering from Hill-Sachs and Bankart lesions, who were then evaluated based on remplissage and Bankart repair. It led to significant improvement of active forward elevation and internal rotation compared with baseline assessment. It concludes that remplissage enables the surgeon to address large humeral defects with a low postoperative recurrence.

Background: Soccer is the most common cause of sporting fracture, but little is known about patient outcome after such fractures. Purpose: To describe the epidemiological characteristics of soccer-related fractures, their outcomes, and the likelihood of return to soccer after injury in a known United Kingdom population at all skill levels. Study Design: Descriptive epidemiology study. Methods: All soccer fractures during 2007-2008 in the Lothian population were prospectively collected, with the diagnosis confirmed by an orthopaedic surgeon when patients attended the only adult orthopaedic service in Lothian. Patients living outside the region were excluded from the study. Patients were contacted in August 2010 to ascertain their progress in returning to soccer. Results: A total of 367 fractures were recorded over the study period in 357 patients; 312 fractures (85%) in 303 patients (85%) were followed up, with a mean interval of 30 months (range, 24-36 months). The mean time for return to soccer from injury was 15 6 17 weeks (range, 0-104 weeks). For patients with lower limb injuries, the mean time was 26 6 22 weeks (range, 4-104 weeks) compared with 9 6 8 weeks for patients with upper limb injuries (range, 0-64 weeks). Fourteen percent of the whole cohort did not return to soccer; 83% returned to soccer at the same level or higher. Thirty-nine percent had ongoing related problems; however, only 8% had impaired soccer ability because of these problems. Fractures with the highest morbidity in not returning to soccer were to the clavicle (24%), distal radius (21%), and tibial diaphysis (20%). Conclusion: Most patients sustaining a fracture while playing soccer will return to soccer at a similar level. While over one third of them will have persisting symptoms 2 years after injury, for the majority, this will not impair their soccer ability. [ABSTRACT FROM AUTHOR]

Background: A recent meta-analysis found that generalized joint hypermobility is a risk factor for knee injuries during contact sports. The effect of hypermobility on the incidence of injuries in elite-level professional soccer players is not known.Purpose: To compare the incidence of injury between hypermobile and nonhypermobile elite-level male professional soccer players.Study Design: Cohort study; Level of evidence, 2.Methods: Fifty-four players from an English Premier League soccer club were assessed for hypermobility, using the 9-point Beighton scale (threshold, 4 points or above), at the start of the 2009-2010 season. Time-loss injuries and individual exposure times were recorded during all club training sessions and matches throughout the entire season.Results: Mean ± standard deviation incidence of injuries was 11.52 ± 11.39 injuries/1000 h, and the prevalence of hypermobility was 33.3% (18 of 54 players). There were 133 injuries during 13 897.5 hours of exposure. During the season, hypermobile participants had a higher incidence of injuries (mean [95% confidence interval] difference, 15.65 [9.18-22.13] injuries/1000 h; P = .001) and were more likely to experience at least 1 injury, a reinjury, and a severe injury compared with nonhypermobile participants. There were 9 severe knee injuries in hypermobile participants, of which 6 were cartilage injuries.Conclusion: There was an increased incidence of injury in hypermobile elite-level professional soccer players from an English Premier League club, resulting in more missed days from training and match play. These findings suggest a need for routine screening for hypermobility in professional soccer. [ABSTRACT FROM PUBLISHER]

Background: Posterolateral corner (PLC) injuries are difficult to diagnose and cause significant morbidity. The ideal method for the dial test and its accuracy remain unclear.Purpose: This study compares the accuracy of measuring tibial external rotation at the skeletal level to measuring the patella-tubercle angle (PTA) and the thigh-foot angle (TFA) in the supine position to assess the most accurate method to measure rotation during the dial test.Study Design: Controlled laboratory study.Methods: Measurements were compared simultaneously using rotational goniometers at a cutaneous splint over the tibia, at a foot splint, and directly from the tibial skeleton. Six lower limbs were used. The femur was held rigidly and the knee tested at 90° and 30° of flexion. External rotation torque up to 8 N·m was applied through the foot splint, and the rotations were measured by 2 testers.Results: Measurements at the tibial splint and directly on the tibia showed significant correlation at both knee flexion angles. The mean tibial external rotation was 24° at 90° of flexion and 26° at 30° of flexion (P < .05). The soft tissue effect caused the tibial splint to overestimate rotations by a mean of 6° and 9° at 90° and 30° of flexion, respectively. Foot splint measurements did not correlate significantly with tibial rotation, overestimating rotations by a mean of 103%. Intratester and intertester intraclass correlations were significant for the skin-mounted tibial splint measurements at both flexion angles but not for foot splint measurements at either flexion angles.Conclusion: Rotation of the foot did not accurately represent the tibial external rotation at the knee, which could be measured more accurately by an instrument resting on the skin via a molded tibial splint. These results suggest that the PTA, and not the TFA, should be used in the dial test. This would support the use of the supine position during the dial test.Clinical Relevance: The dial test is a commonly used method for diagnosing PLC injuries. This study helps to identify the ideal position and measuring points to use for this test; measurements based on the tibia were more accurate than those that used rotation of the foot. [ABSTRACT FROM AUTHOR]

Background: The posterolateral corner (PLC) resists tibial varus angulation, external rotation, and, to a lesser extent, posterior translation. It is important that reconstructions of posterolateral knee injuries restore joint laxity and patient function, but residual laxities are often observed.Hypothesis: The knee laxity after a new 4-strand PLC reconstruction would be closer to normal than after a 2-strand “modified Larson” reconstruction.Study Design: Controlled laboratory study.Methods: Fourteen intact cadaveric knees were mounted in a 6 degrees of freedom rig and subjected to the following external loading conditions: a 90-N posterior tibial force, a 5-N·m external rotation torque, and 5-N·m varus moment. Knee kinematics were recorded with an active optical tracking system for the intact, PLC-deficient, modified Larson PLC reconstruction and 4-strand PLC reconstruction.Results: With external tibial torque, the rotational laxity in 4-strand reconstruction was significantly less than in the PLC-deficient (P < .0001) and modified Larson reconstruction (P = .0112) and did not differ significantly from intact laxity at any angle of flexion. In response to posterior load, posterior translation did not change in any of the tested conditions, while the coupled external rotation laxity in 4-strand PLC reconstruction was significantly less than in the PLC-deficient (P < .0001) and modified Larson reconstruction (P < .0486) and was not significantly different from the intact movements for both reconstructions. The varus angulation-versus-flexion curves were significantly different between the PLC-deficient and both PLC reconstructions (P < .0001). The varus laxity was not significantly different between the modified Larson reconstruction, the 4-strand reconstruction, and the intact knee.Conclusion: This study showed that the rotational knee laxity in response to both external rotation and posterior translation load were significantly better after the 4-strand PLC reconstruction than after the modified Larson reconstruction, although significant differences were not found between the 2 procedures for varus laxity.Clinical Relevance: The 4-strand PLC reconstruction may produce a better biomechanical outcome, especially during external rotation and posterior translation tibial load. The authors suggest that this relates to load sharing among 4 graft strands crossing the joint. [ABSTRACT FROM AUTHOR]

Background: Cold water immersion reduces exercise-induced muscle damage. Benefits may partly arise from a decline in limb blood flow; however, no study has comprehensively investigated the influence of different degrees of cooling undertaken via cold water immersion on limb blood flow responses.Purpose: To determine the influence of cold (8°C) and cool (22°C) water immersion on lower limb and cutaneous blood flow.Study Design: Controlled laboratory study.Methods: Nine men were placed in a semireclined position and lowered into 8°C or 22°C water to the iliac crest for two 5-minute periods interspersed with 2 minutes of nonimmersion. Rectal and thigh skin temperature, deep and superficial muscle temperature, heart rate, mean arterial pressure, thigh cutaneous blood velocity (laser Doppler), and superficial femoral artery blood flow (duplex ultrasound) were measured during immersion and for 30 minutes after immersion. Indices of vascular conductance were calculated (flux and blood flow/mean arterial pressure).Results: Reductions in rectal temperature (8°C, 0.2° ± 0.1°C; 22°C, 0.1° ± 0.1°C) and thigh skin temperature (8°C, 6.2° ± 0.5°C; 22°C, 3.2° ± 0.2°C) were greater in 8°C water than in 22°C (P < .01). Femoral artery conductance was reduced to a similar extent immediately after immersion (~30%) and 30 minutes after immersion (~40%) under both conditions (P < .01). In contrast, there was less thigh cutaneous vasoconstriction during and after immersion in 8°C water compared with 22°C (P = .01).Conclusion: These data suggest that immersion at both temperatures resulted in similar whole limb blood flow but, paradoxically, more blood was distributed to the skin in the colder water. This suggests that colder temperatures may be associated with reduced muscle blood flow, which could provide an explanation for the benefits of cold water immersion in alleviating exercise-induced muscle damage in sports and athletic contexts.Clinical Relevance: Colder water temperatures may be more effective in the treatment of exercise-induced muscle damage and injury rehabilitation because of greater reductions in muscle blood flow. [ABSTRACT FROM PUBLISHER]

Background: Although both anatomic double-bundle and single-bundle anterior cruciate ligament reconstruction procedures are in use, it remains controversial whether the anatomic double-bundle procedure is biomechanically superior.Hypothesis: The anatomic double-bundle procedure would be better than both laterally placed anatomic and nonanatomic trans-tibial single-bundle procedures at restoring to normal the tibial anterior translation, internal rotation, and pivot-shift instability. It was also hypothesized that tibial internal rotation would be closer to normal after laterally placed anatomic single-bundle reconstruction than after the nonanatomic reconstruction.Study Design: Controlled laboratory study.Methods: Eight cadaveric knees were mounted in a 6 degrees of freedom rig and tested using the following loading conditions: 90-N anterior and posterior tibial forces, 5-N·m internal and external tibial rotation torques, and a simulated pivot-shift test. Tibiofemoral kinematics during the flexion-extension cycle were recorded with an optical tracking system for (1) intact, (2) anterior cruciate ligament—deficient knee, (3) anatomic double-bundle reconstruction, (4) nonanatomic single-bundle reconstruction, and (5) laterally placed single-bundle reconstruction.Results: Rotational laxity with internal tibial torque and anterior laxity in the simulated pivot shift were significantly less in the double-bundle reconstruction and laterally placed single-bundle reconstruction compared with the nonanatomic single-bundle reconstruction. There were no significant differences between the 3 procedures when anterior and posterior tibial translation forces and external rotation torques were applied. In addition, there were no significant differences between the double-bundle reconstruction and laterally placed single-bundle reconstruction.Conclusion: The postoperative rotational and pivot-shift laxity after anatomic double-bundle anterior cruciate ligament reconstruction was significantly better than that after nonanatomic single-bundle reconstruction. However, there were no significant differences between the double-bundle reconstruction and laterally placed single-bundle reconstruction.Clinical Relevance: This work suggests that a single-bundle reconstruction may be better able to control both knee laxity and pivot-shift instability if the femoral tunnel is moved to a more lateral position and that then the double-bundle reconstruction may not offer significant further advantages. [ABSTRACT FROM AUTHOR]