BACKGROUND:

In recent years, there has been a documented increase in the number of professional baseball players on the disabled list and the total number of days on the disabled list. Pitchers account for the largest number of disabled list reports.

PURPOSE:

To examine the relationship between magnetic resonance imaging (MRI) findings in asymptomatic professional pitchers and subsequent time on the disabled list (DL).

STUDY DESIGN:

Cohort study (Prognosis); Level of evidence, 2.

METHODS:

A total of 21 asymptomatic professional pitchers from a single Major League Baseball (MLB) organization underwent preseason MRIs of their dominant shoulder from 2001 to 2010. Asymptomatic was defined as no related DL stays in the 2 seasons before the MRI. These studies were reevaluated by a fellowship-trained musculoskeletal radiologist who was blinded to patient name, injury history, and baseball history. A second investigator who was blinded to the MRI results collected demographic data, total career number of innings pitched, and any subsequent DL reports for each subject.

RESULTS:

The mean age at the time of MRI was 29.04 years (range, 20-39 years). Eleven of 21 pitchers had a rotator cuff tear (RCT): 9 had an articular surface tear (AST), and 2 had a full-thickness rotator cuff tear (FTT). Ten had superior labral anterior posterior (SLAP) tears, and 13 had either anterior or posterior labral tears. There was a statistically significant relationship between the number of innings pitched and presence of an RCT (AST + FTT). The mean number of career innings pitched by those with an RCT was 1014 compared with a mean of 729 innings pitched in pitchers without an RCT (P < .01). In addition, the number of career innings pitched was moderately correlated with presence of RCT (r = 0.46) and presence of superior and anterior/posterior labral tears (r = 0.43). There were no statistically significant findings between any single preseason MRI finding and subsequent time on the DL.

CONCLUSION:

The MRI findings in asymptomatic MLB pitchers do not appear to be related to near future placement on the DL. However, there was a significant difference in numbers of innings pitched between pitchers who had an RCT and those who did not and a moderate correlation between innings pitched and the presence of RCT as well as the presence of labral lesions. This finding supports the notion that RCT and labral injury in pitchers may result from repetitive overhead motion with subsequent strain on the rotator cuff tendons and glenoid labrum. Asymptomatic shoulder lesions in professional baseball pitchers appear to be more frequent than previously thought.

BACKGROUND:

Glenoid reconstruction with distal tibial allografts offers the theoretical advantage over Latarjet reconstruction of improved joint congruity and a cartilaginous articulation for the humeral head.Hypothesis/

PURPOSE:

To investigate changes in the magnitude and location of glenohumeral contact areas, contact pressures, and peak forces after (1) the creation of a 30% anterior glenoid defect and subsequent glenoid bone augmentation with (2) a flush Latarjet coracoid graft or (3) a distal tibial osteochondral allograft. It was hypothesized that the distal tibial bone graft would best normalize glenohumeral contact areas, contact pressures, and peak forces.

STUDY DESIGN:

Controlled laboratory study.

METHODS:

Eight cadaveric shoulder specimens were dissected free of all soft tissues and randomly tested in 3 static positions of humeral abduction with a 440-N compressive load: 30°, 60°, and 60° of abduction with 90° of external rotation (ABER). Glenohumeral contact area, contact pressure, and peak force were determined sequentially using a digital pressure mapping system for (1) the intact glenoid, (2) the glenoid with a 30% anterior bone defect, and (3) the glenoid after reconstruction with a distal tibial allograft or a Latarjet bone block.

RESULTS:

Glenoid reconstruction with distal tibial allografts resulted in significantly higher glenohumeral contact areas than reconstruction with Latarjet bone blocks in 60° of abduction (4.87 vs 3.93 cm(2), respectively; P < .05) and the ABER position (3.98 vs 2.81 cm(2), respectively; P < .05). Distal tibial allograft reconstruction also demonstrated significantly lower peak forces than Latarjet reconstruction in the ABER position (2.39 vs 2.61 N, respectively; P < .05). Regarding the bone loss model, distal tibial allograft reconstruction exhibited significantly higher contact areas and significantly lower contact pressures and peak forces than the 30% defect model at all 3 abduction positions. Latarjet reconstruction also followed this same pattern, but differences in contact areas and peak forces between the defect model and Latarjet reconstruction in the ABER position were not statistically significant (P > .05).

CONCLUSION:

Reconstruction of anterior glenoid bone defects with a distal tibial allograft may allow for improved joint congruity and lower peak forces within the glenohumeral joint than Latarjet reconstruction at 60° of abduction and the ABER position. Although these mechanical properties may translate into clinical differences, further studies are needed to understand their effects.

CLINICAL RELEVANCE:

Glenoid bone reconstruction with a distal tibial osteochondral allograft may result in significantly improved glenohumeral contact areas and significantly lower glenohumeral peak forces than reconstruction with a Latarjet bone block, which could play a role in improving postoperative outcomes after glenoid reconstruction.

BACKGROUND:

The increased risk of long-term osteoarthritis from concomitant injuries to the menisci or cartilage after an anterior cruciate ligament (ACL) injury in adults is well established. In skeletally immature children, ACL reconstruction is often recommended to reduce the risk of new intra-articular injuries. However, the prevalence and incidence of new injuries after nonoperative treatment of ACL injuries in children are unknown.

PURPOSE:

To prospectively investigate the incidence of new injuries to the menisci and joint cartilage in nonoperatively treated, skeletally immature children with a known ACL injury by use of bilateral 3.0-T MRI.

STUDY DESIGN:

Case series; Level of evidence, 4.

METHODS:

Forty skeletally immature children with a ruptured ACL (41 knees) followed a nonoperative treatment algorithm and were evaluated with bilateral 3.0-T MRI on 2 occasions (MRI1 and MRI2). The intra-articular structures were analyzed by 2 independent MRI radiologists. Monitoring of participation in physical activities was accomplished through a monthly online activity survey. Descriptive statistics and frequencies were extracted from the scoring forms and compared using the Fisher exact test.

RESULTS:

Fourteen girls (35%) and 26 boys (65%) with a mean age of 11.0 ± 1.4 years at the time of injury were included. Time from injury to the final follow-up was 3.8 ± 1.4 years. Eighty-eight percent of the ACL-deficient children confirmed monthly participation in pivoting sports and/or in physical education classes in school. The prevalence of meniscus injuries in the 28 nonreconstructed knees was 28.5% at MRI1 and MRI2, and the incidence of new meniscus and cartilage injuries in the nonreconstructed knees from MRI1 to MRI2 was 3.6%. Thirteen children underwent ACL reconstruction, with a prevalence of meniscus procedures of 46.2%. The incidence of new meniscus injuries from diagnostic MRI to final follow-up was 19.5%. Surgical treatments for meniscus injuries were performed in 8 of the 41 knees.

CONCLUSION:

The incidence of new injuries to menisci and joint cartilage was low between MRI1 and MRI2 in the 28 nonreconstructed knees. Thirty-two percent of the knees required ACL reconstruction, and 19.5% required meniscus surgeries during the 3.8 ± 1.4 years of follow-up from injury. Further follow-up is needed to evaluate the long-term knee health in these children.

BACKGROUND:

Few studies have documented catastrophic head and neck injuries in judo, but these injuries deserve greater attention.

PURPOSE:

To determine the features of catastrophic head and neck injuries in judo.

STUDY DESIGN:

Descriptive epidemiological study.

METHODS:

This study was based on the accident reports submitted to the All Japan Judo Federation's System for Compensation for Loss or Damage. A total of 72 judo injuries (30 head, 19 neck, and 23 other injuries) were reported between 2003 and 2010. The investigated parameters were mechanism of injury, age at time of injury, length of judo experience, diagnosis, and outcome.

RESULTS:

Among head injuries, 27 of 30 (90%) occurred in players younger than 20 years of age. The relationship between age, mechanism, and location of injury was more relevant when players younger than 20 years incurred head injury while being thrown (P = .0026). Among neck injuries, 13 of 19 (68%) occurred in players with more than 36 months of experience. The relationship between experience, mechanism, and location of injury was more relevant when experienced players incurred neck injury while executing an offensive maneuver (P = .0294). Acute subdural hematoma was diagnosed in 94% of head injuries. The outcomes of head injury were as follows: 15 players died; 5 were in a persistent vegetative state; 6 required assistance because of higher brain dysfunction, hemiplegia, or aphasia; and 4 had full recovery. Among neck injuries, 18 players were diagnosed with cervical spine injury, 11 of whom had fracture-dislocation of the cervical vertebra; there was also 1 case of atlantoaxial subluxation. The outcomes of neck injury were as follows: 7 players had complete paralysis, 7 had incomplete paralysis, and 5 had full recovery.

CONCLUSION:

Neck injuries were associated with having more experience and executing offensive maneuvers, whereas head injuries were associated with age younger than 20 years and with being thrown.

BACKGROUND:

Osteochondritis dissecans (OCD) is an acquired lesion of the subchondral bone that may result in separation and instability of the overlying articular cartilage. Unstable lesions must be treated surgically to reestablish the joint surface as anatomically as possible.Hypothesis/

PURPOSE:

The aim of this study was to evaluate the potential of a biomimetic osteochondral scaffold to treat OCD by analyzing the results obtained at 2-year follow-up. The hypothesis was that this scaffold, which was developed to treat the entire osteochondral unit, might restore the articular surface and improve symptoms and function in patients affected by knee OCD.

STUDY DESIGN:

Case series; Level of evidence, 4.

METHODS:

Twenty-seven consecutive patients (19 men, 8 women; age [mean ± SD], 25.5 ± 7.7 years) who were affected by symptomatic knee OCD of the femoral condyles (average defect size 3.4 ± 2.2 cm(2)), grade 3 or 4 on the International Cartilage Repair Society (ICRS) scale, were enrolled and treated with the implantation of a 3-layer collagen-hydroxyapatite scaffold. Patients were prospectively evaluated by subjective and objective International Knee Documentation Committee (IKDC) and Tegner scores preoperatively and at 1- and 2-year follow-up. An MRI was also performed at the 2 follow-up times.

RESULTS:

A statistically significant improvement in all clinical scores was obtained at 1 year, and a further improvement was found the following year. At the 2-year follow-up, the IKDC subjective score had increased from 48.4 ± 17.8 preoperatively to 82.3 ± 12.2, the IKDC objective evaluation from 40% to 85% of normal knees, and the Tegner score from 2.4 ± 1.7 to 4.5 ± 1.6. The MRI evaluations showed good defect filling and implant integration but also inhomogeneous regenerated tissue and subchondral bone changes in most patients at both follow-up times. No correlation between the MOCART (magnetic resonance observation of cartilage repair tissue) score and clinical outcome was found.

CONCLUSION:

This biomimetic osteochondral scaffold seems to be a valid treatment option for knee OCD, showing a good clinical outcome at 2-year follow-up. Moreover, the improvement was not correlated with lesion size, so large lesions can benefit from this implant. Less favorable findings were obtained with MRI evaluation.

BACKGROUND:

In anterior cruciate ligament (ACL) reconstruction, the transtibial (TT) technique often creates a nonanatomically placed femoral tunnel, which is a frequent cause of surgical failure and postsurgical knee instability. Several studies reported that drilling the femoral tunnel through an anteromedial portal (AMP) yields a more anatomic tunnel position compared with the TT technique.

PURPOSE:

To compare the effectiveness of these two surgical techniques in restoring the intact knee joint kinematics during a physiological loading situation.

STUDY DESIGN:

Controlled laboratory study.

METHODS:

Twenty-four patients (TT, n = 12; AMP, n = 12; sex, weight, and height matched, and half with dominant leg involved) who underwent unilateral single-bundle ACL reconstruction by the same surgeon were recruited. Twenty healthy patients with no history of lower limb injuries were recruited as the control group. Tibiofemoral joint motion in 6 degrees of freedom (3 translations and 3 rotations) was determined during level walking by using a least mean square-based optimization algorithm. A redundant marker set was used to improve the accuracy of the motion analysis. Knee joint kinematics as well as spatiotemporal parameters were compared between these two techniques.

RESULTS:

The AMP technique restored the anterior-posterior translation of the knee joint, while the TT technique resulted in significantly greater (TT, 22.2 mm vs controls, 13.2 mm; P < .01) anterior femoral translations than in the healthy controls during the swing phase. Excessive femoral external (tibial internal) rotation (3.8°; P < .05) was found at midstance in the knees that were reconstructed using the TT technique; using the AMP technique, the external rotation offset was greatly reduced during the stance phase. However, knees repaired using the AMP technique were significantly less extended (5°; P < .05) compared with the knees of the controls during the late stance phase. Neither surgical technique restored the superior-inferior femoral translation to the intact level during the swing phase.

CONCLUSION:

The AMP technique better restores the anterior-posterior translation during the swing phase and femoral external rotation at midstance than the TT technique does. However, the AMP technique is also correlated with an extension loss during the late stance phase.

CLINICAL RELEVANCE:

The AMP femoral tunnel drilling technique can improve overall knee joint stability, but the increased difficulty with full extension may need to be considered.

BACKGROUND:

Infections after anterior cruciate ligament reconstruction (ACLR) can be devastating. Hamstring tendon autografts may be more susceptible to infections than other graft types.

PURPOSE:

To determine the incidence of surgical site infections (SSIs) in a large sample of patients who underwent ACLR and to evaluate the risk of superficial and deep SSIs associated with grafts used for ACLR.

STUDY DESIGN:

Cohort study; Level of evidence, 2.

METHODS:

All primary ACLRs performed between February 2005 and September 2010 registered in the Kaiser Permanente ACLR registry were included in the study. The graft types evaluated included the bone-patellar tendon-bone (BPTB) autograft, hamstring tendon autograft, and allograft (all types). The main end point of the study, SSIs (deep and superficial), was prospectively ascertained using an electronic screening algorithm and adjudicated by the principal investigator. Descriptive statistics were used to describe the cohort, and logistic regression models were used to evaluate the likelihood of an infection.

RESULTS:

There were 10,626 cases that fit the study criteria. The overall cohort was 64% male, mean age was 29 ± 11 years, and mean body mass index (BMI) was 27 ± 5 kg/m(2). The overall incidence of SSIs was 0.48% (n = 51), with 17 (0.16%) superficial infections and 34 (0.32%) deep infections. Hamstring tendon autografts (n = 20; 0.61%) had the highest incidence of deep SSIs of the graft types (BPTB autograft, n = 2 [0.07%]; allograft, n = 12 [0.27%]; P < .001). After adjusting for age, sex, and BMI, the likelihood of a patient with a hamstring autograft having a deep SSI was 8.24 times higher (95% CI, 1.91-35.55; P = .005) than someone receiving a BPTB autograft. The risk of infections in allografts was not statistically significantly higher than BPTB autografts.

CONCLUSION:

The overall SSI rate after ACLR was 0.48%. Deep SSIs were identified in 0.32% of the ACLR cases and superficial SSIs in 0.16%. An 8.2-times higher risk of SSIs was observed in hamstring tendon autografts compared with BPTB autografts. No difference in SSI incidence was identified between allografts and BPTB autografts. Surgeons should bear in mind that although the overall infection rates after ACLR are low, there is an increased risk of deep infections with hamstring tendon autografts.