John D. Polousky

A Review of Knowledge in Osteochondritis Dissecans: 123 Years of Minimal Evolution from König to the ROCK Study Group

BackgroundOsteochondritis dissecans (OCD) was first described to provide an explanation for the nontraumatic development of loose bodies within a joint. Despite many reports on the subject, there remains no clear understanding of the etiology, natural history, or treatment.Questions/purposesThis review was undertaken to delineate (1) the etiology of OCD; (2) the presentation and locations; (3) the most appropriate imaging modalities; and (4) the most effective treatment strategies.MethodsWe reviewed the English literature using a database compiled from a Medline search for “osteochondritis dissecans”. We identified 1716 publications, 1246 of which were in English. After exclusions, we reviewed 748 articles and of these cited 85. The observations of each study were then synthesized into this report.ResultsThere appears to be no consensus concerning the etiology of OCD lesions. The presentations and locations are variable, but the knee, ankle, and elbow are most commonly involved. Although plain film assessment is important in OCD, there appears to be a trend toward the use of MRI, but the preferred sequences are in evolution. We found no consensus on the treatment of these lesions, related in part to the lack of agreement of methods for assessing outcomes.ConclusionsDespite more than a century of study, we have made little advancement in our understanding of OCD. A study group has been formed to address this issue and actively seeks to answer these unknown issues regarding OCD.

Comparison of Allograft Versus Autograft Anterior Cruciate Ligament Reconstruction Graft Survival in an Active Adolescent Cohort

Background: Graft selection for anterior cruciate ligament (ACL) reconstructive surgery is a controversial topic. Few studies have compared graft outcomes in adolescents. Purpose: To identify factors related to ACL graft failure in an adolescent cohort. Study Design: Case-control study; Level of evidence, 3. Methods: After institutional review board approval was obtained, adolescent subjects (age range, 11-18 years) who underwent primary ACL reconstruction surgery at a large tertiary pediatric hospital between July 2005 and July 2009 were identified through a query of International Classification of Diseases, 9th Revision, diagnostic and Current Procedural Terminology codes. Subject data were obtained by means of a retrospective chart review, phone survey, and the administration of functional knee outcome instruments. A multivariate Cox proportional hazards regression analysis was used to analyze factors related to graft survival. Results: The average ages at surgery in the allograft (n = 38) and autograft (n = 35) groups were 15.29 ± 2.24 and 15.60 ± 1.57 years, respectively. There were 11 graft failures (28.95%) in the allograft group compared with 4 graft failures (11.43%) in the autograft group. In the multivariate model, graft type (P = .0352) and postoperative knee laxity according to the Lachman test (P = .0217) were the only variables significantly related to graft survival. The hazard of graft failure was 4.4 (95% CI, 1.23-18.89) times greater in the allograft group compared with the autograft group. The hazard of graft failure was 5.28 times (95% CI, 1.1-12.72; P = .0217) greater for a subject who demonstrated increased postoperative knee laxity relative to the contralateral knee. The risk for autograft failure tended to remain constant 24 to 48 months after initial surgery, whereas the risk for allograft failure continued to increase during postoperative months 24 to 48. There were no differences (P > .05) between the allograft and autograft groups with respect to International Knee Documentation Committee score, Lysholm score, and the rate of return to previous activity level. Conclusion: Graft type and postoperative knee laxity were identified as significant predictors of graft survival. On the basis of this large retrospective cohort, we recommend the use of autogenous grafts in children and adolescents undergoing primary, transphyseal ACL reconstruction. Patients who demonstrate increased translation during a postoperative Lachman test should be carefully followed because of concerns for subsequent graft failure.

A survey of physician opinion: adolescent midshaft clavicle fracture treatment preferences among POSNA members.

Background Based on recent evidence of inconsistent outcomes after the closed treatment of adult midshaft clavicle fractures, the management of similar fracture patterns in adolescents is being reevaluated. The primary aim of this study is to report current treatment preferences for adolescent midshaft clavicle fractures among pediatric orthopaedic physicians and to determine if recent adult literature has influenced clinical decision making. Methods An invitation email to a cross-sectional, web-based survey was sent to all members of the Pediatric Society of North America. With reference to adolescent sex and age, respondents were prompted to indicate their treatment preference (operative vs. nonoperative) in 4 common midshaft clavicle fracture patterns. The respondents were also asked to indicate if the following factors: findings in current literature supporting operative fixation in adults, arm dominance, and/or athletic status, influenced their preference for operative versus nonoperative management. Results Of the 949 Pediatric Society of North America members, 302 responded in full (32% response rate). The majority of physicians preferred nonoperative treatment for all fracture patterns. A logistic regression analysis revealed: older adolescent age (12 to 15 y vs. 16 to 19 y.) and evidence in recent adult literature (influence vs. no influence) to be significantly (P<0.01) predictive of physician preference toward operative fixation in angulated, displaced, and isolated segmental clavicle fracture patterns. Physician years of experience (<5 y vs. >5 y) significantly predicted treatment preferences in isolated segmental fractures only. Conclusions The percentage of physicians in favor of operative fixation tended to increase in reference to older adolescents and more severe fracture patterns but, nonoperative management was preferred in all fracture patterns. Evidence in recent adult literature was found to be the most significant factor influencing treatment preferences in this survey. Randomized controlled trials are needed to evaluate the efficacy of primary operative fixation of midshaft clavicle fractures in adolescent populations. Level of Evidence Cross-sectional electronic survey; level V-expert opinion.

The Anterolateral Ligament of the Knee: An Inconsistent Finding in Pediatric Cadaveric Specimens.

Background: The anterolateral ligament (ALL) of the knee has been identified as a structure that limits internal rotation, and thus, affects the pivot shift mechanism. It has previously been reported in a high percentage of adult subjects. The purpose of the current study was to evaluate whether the ALL could be identified on pediatric cadaveric knee specimens and compare these findings to previously published reports. Methods: Eight skeletally immature cadaver knee specimens were examined through gross dissection: ages 3 months, 4 months, 1 year, 2 years, 3 years, 3 years, 8 years, and 10 years. There were 3 male and 5 female (7 right, 1 left) specimens. The presence or absence of the ALL was documented in each specimen, through dissection, intermittent internal and external rotation of the tibia, and anterior translation of the tibia, to produce tension of the lateral collateral tissues and joint capsule. These dissections were performed by a group of fellowship-trained orthopaedic surgeons. Results: The iliotibial band, entire lateral joint capsule, lateral collateral ligament, and popliteus were readily identified in each specimen. In 7 specimens, a distinct ALL structure was not identified during dissection. The ALL was identified in 1 of 8 specimens (1-year-old female, right knee). The ALL was further delineated under applied internal rotational stress. Conclusions: Previous research has suggested that this ligament is present in the majority of adult specimens. This finding was not reproduced in the current study of pediatric cadaveric specimens, where only one of 8 specimens had an identifiable ALL. This suggests that this ligament may develop later in life, after physiological loads are applied to the joint capsule. Further research in both adult and pediatric knees needs to be conducted to further elucidate the development of this ligament, and the role of this structure in knee stability. Clinical Relevance: The ALL is a knee ligament that has been described in adults. However, it is unclear whether this structure is present or fully developed in younger populations. The current study sought to identify the ALL in pediatric cadaver knee specimens, identifying this structure in only one of 8 specimens. The findings of this study suggest that the ALL may be an inconsistent structure in the pediatric population.

Novel Radiographic Feature Classification of Knee Osteochondritis Dissecans A Multicenter Reliability Study

Background: Osteochondritis dissecans (OCD) is a vexing condition for patients, parents, and physicians because of the frequent slow healing and nonhealing that leads to prolonged treatment. Several features on plain radiographs have been identified as predictors of healing, but the reliability of their measurement has not been established. Purpose: To determine the inter- and intrarater reliability of several radiographic features used in the diagnosis, treatment, and prognosis of OCD femoral condyle lesions. Study Design: Cohort study (Diagnosis); Level of evidence, 3. Methods: Pretreatment anteroposterior, lateral, and notch radiographs of 45 knees containing OCD lesions of the medial or lateral femoral condyle were reviewed in blinded fashion by 7 orthopaedic physician raters from different institutions over a secure web portal at 2 time points over a month apart. Classification variables included lesion location, growth plate maturity, parent bone radiodensity, progeny bone fragmentation, progeny bone displacement, progeny bone contour, lesion boundary, and radiodensity of the lesion center and rim. Condylar width and lesion size were measured on all views. Interrater reliability was assessed using free-marginal kappa and intraclass correlations. Intrarater reliability was assessed using the Cohen kappa, linear-weighted kappa, and intraclass correlations based on measurement type. Results: Raters had excellent reliability for differentiating medial and lateral lesions and growth plate maturity and for measuring condylar width and lesion size. In the subset of knees with visible bone in the lesion, the fragmentation, displacement, boundary, central radiodensity, and contour (concave/nonconcave) of the lesion bone were classified with moderate to substantial reliability. The radiodensity of the lesion rim and surrounding epiphyseal bone were classified with poor to fair reliability. Conclusion: Many diagnostic features of femoral condyle OCD lesions can be reliably classified on plain radiographs, supporting their future testing in multifactorial classification systems and multicenter research to develop prognostic algorithms. Other radiographic features should be excluded, however, because of poor reliability.

The American Academy of Orthopaedic Surgeons Evidence-Based Guideline on Management of Anterior Cruciate Ligament Injuries

This article was updated on June 30, 2015, because of a previous error. The name of one of the authors, which had previously read “Gregory D. Meyer, PhD,” has been corrected to read “Gregory D. Myer, PhD.” An erratum has been published: J Bone Joint Surg Am. 2015 Aug 5;97(15):e57. The AAOS Evidence-Based Guideline on Management of Anterior Cruciate Ligament Injuries includes both diagnosis and treatment. This clinical practice guideline has been endorsed by the National Academy of Sports Medicine (NASM), the American Orthopaedic Society for Sports Medicine (AOSSM), the National Athletic Trainers’ Association (NATA), and the American Academy of Physical Medicine and Rehabilitation (AAPM&R). This brief summary of the AAOS Clinical Practice Guideline contains a list of the recommendations and the rating of strength based on the quality of the supporting evidence. Discussion of how each recommendation was developed and the complete evidence report are contained in the full guideline at www.aaos.org/guidelines. ### ACL HISTORY AND PHYSICAL Strong evidence supports that the practitioner should obtain a relevant history and perform a musculoskeletal exam of the lower extremities, because these are effective diagnostic tools for ACL injury. Strength of Recommendation: Strong ★★★★ ### ACL RADIOGRAPHS In the absence of reliable evidence, it is the opinion of …

The relationship of the femoral physis and the medial patellofemoral ligament in children: a cadaveric study.

Background: Patellar dislocations are common in skeletally immature athletes, and the medial patellofemoral ligament (MPFL) is an important primary restraint to lateral patellar translation. The relationship between the MPFL femoral origin footprint and femoral physis is unclear. The purpose of this study was to evaluate the MPFL femoral origin footprint and its relationship to the femoral physis in skeletally immature anatomic specimens. Methods: Six skeletally immature cadaver knee specimens were examined through gross dissection (group A: 1, 11, and 11 mo; and group B: 8, 10, and 11 y). Metallic markers were placed at the center of the MPFL femoral origin footprint. Computed tomography scans for each specimen were analyzed. The MPFL footprint width, and the vertical distances from the center and proximal extent of the MPFL footprint to the medial aspect of the physis were measured. Results: The mean width of the MPFL femoral origin footprint was 0.70 cm (0.48 to 1.09 cm) and 1.12 cm (1.03 to 1.29 cm) for groups A and B, respectively. The mean distance from the center of the MPFL origin footprint to medial aspect of the distal femoral physis was 0.90 cm (0.52 to 1.30 cm) and 0.40 cm (0.00 to 0.86 cm) distal to the physis for groups A and B, respectively. The mean distance from the proximal extent of the MPFL origin footprint to the medial aspect of the femoral physis was −0.55 cm (−0.28 to −1.03 cm) and 0.16 cm (−0.34 to 0.64 cm) for groups A and B, respectively. Conclusions: All subjects were found to have a center of the MPFL origin footprint at or below the physis. The proximal extent of the MPFL origin footprint was found to extend above the physis in the 2 older specimens. Clinical Relevance: The relationship of the MPFL origin footprint to the femoral physis in the skeletally immature is not well understood. These dissections may be useful to surgeons performing MPFL reconstructions in skeletally immature patients.

Novel Application of Magnetic Resonance Imaging Demonstrates Characteristic Differences in Vasculature at Predilection Sites of Osteochondritis Dissecans

Background: Understanding the pathogenesis of osteochondrosis/osteochondritis dissecans and other developmental orthopaedic diseases that are thought to occur secondary to defects in vascular supply to growth/epiphyseal cartilage has been hampered by the inability to image the vasculature in this tissue. This is particularly true in human beings due to limitations of current imaging techniques and the lack of availability of appropriate cadaveric samples for histological studies. Hypothesis: Susceptibility-weighted imaging, an MRI sequence, allows identification of characteristic differences in the vascular architecture in species that are affected by osteochondrosis/osteochondritis dissecans on the femoral condyle (humans and pigs) versus a species that is free of the disease (goat). Study Design: Controlled laboratory study. Materials: Distal femora from cadavers of juvenile humans (n = 5), pigs (n = 3), and goats (n = 3) were scanned in a 9.4-T MRI scanner using susceptibility-weighted imaging. Three-dimensional reconstructions were created, and minimum intensity projections were calculated in 3 planes to enhance visualization of the vascular architecture. Results: Susceptibility-weighted imaging allowed clear visualization of the epiphyseal vasculature in all species. Vascular architecture, with vessels primarily arising from the perichondrium, was similar in humans and pigs, which are predisposed to osteochondrosis/osteochondritis dissecans, and was starkly different from that present in goats, a species in which there are no reports of osteochondrosis/osteochondritis dissecans. Furthermore, vessels in the distal femoral predilection site disappeared with age in humans in a pattern similar to that reported previously in pigs. Conclusion: Nearly identical vascular architecture at the shared primary predilection site of osteochondrosis/osteochondritis dissecans in the femoral condyles in human beings and pigs suggests that vascular failure, which is known to be central to the pathogenesis of this disease in pigs, may also play a role in humans. Clinical Relevance: This assumption of a shared pathogenesis is supported by the pattern of disappearance of vessels with age at the primary predilection site of osteochondritis dissecans in humans, which is essentially identical to that which has been reported in pigs. Susceptibility-weighted imaging will likely help further elucidate this potential relationship in the future.

The Relationship of the Femoral Physis and the Medial Patellofemoral Ligament in Children A Cadaveric Study

Background: Young athletes sustain patellar dislocations in a variety of sports. The medial patellofemoral ligament (MPFL) is a critical structure that functions as an anatomic checkrein to help prevent lateral patellar dislocation. Reconstruction of this ligament is challenging in patients with open physes because of concerns about iatrogenic damage to the femoral physis. Purpose: To evaluate the relationship of the distal femoral physis and the MPFL. Study Design: Descriptive laboratory study. Methods: In 15 cadaveric, pediatric knees (age, 7-11 years), markers were placed at the proximal/distal limits of the MPFL femoral attachment and were evaluated with computed tomography. The distance from the MPFL attachment midpoint to the most medial aspect of the distal femoral physis was measured. Results: The mean femoral width of the MPFL was 8.1 mm (range, 4.3-13.8 mm). The femoral MPFL midpoint was distal to the femoral physis in 11 specimens and proximal to the physis in 4 specimens. The most proximal portion of the MPFL femoral attachment extended above the medial physis in 7, was at the physis in 5, and was below the physis in 3 specimens. One specimen had the entire MPFL femoral attachment above the physis. For knees with the MPFL midpoint above the medial physis, the distance between the center of the MPFL and physis was 3.3 mm (range, 0.3-7.1 mm). For knees with the MPFL below the medial physis, the distance between the center of the MPFL and physis was −6.8 mm (range, −0.7 to −22.0 mm). Conclusion: The relationship of the femoral attachment of the MPFL and the medial femoral physis shows some anatomic variation. In all cases, the MPFL is close to the medial femoral physis, but the midpoint of the MPFL is at, slightly above, or slightly below the physis. Clinical Relevance: The relationship of the MPFL femoral attachment footprint to the femoral physis in the skeletally immature patient is not well understood, and access to pediatric cadaveric tissue is very limited. This small series demonstrates that there is considerable variation in the relationship between the MPFL and distal femoral physis. This anatomic information may guide MPFL reconstruction technique in young patients and reduce the risk of iatrogenic physeal arrest on the femur.

Subscapularis tendon injuries in adolescents: a report of 2 cases.

Background Although shoulder injuries in adolescents are relatively common, injuries to the rotator cuff are relatively rare and not well characterized in the literature. We review 2 cases of adolescent subscapularis tendon avulsions treated surgically. Methods The 2 patients were high-level athletes, 1 is a baseball pitcher and the other is a boxer. Both were injured during participation in their respective sports. In each case, the diagnosis was made by magnetic resonance imaging. Patients underwent an open repair by a deltopectoral approach, using suture anchors for fixation. Results After surgery both patients regained full range of motion and returned to their previous levels of activity. Both patients scored 30 and 35 on the American Shoulder and Elbow Surgeons and University of California, Los Angeles shoulder instruments, respectively. Conclusions Subscapularis tendon injuries in adolescents are rare. Diagnosis requires careful attention to the physical examination and imaging. A positive lift-off test, belly-press test, or increased passive external rotation should prompt an early magnetic resonance imaging. Good results and return to previous levels of activity can be achieved with open repair. Level of Evidence IV.