Incidence of Meniscal Entrapment and Associated Knee Injuries in Tibial Spine Avulsions.

BACKGROUND: Tibial spine avulsions (TSA) have historically been treated as isolated injuries. Data on associated injuries are limited with existing literature reporting wide ranging incidences. The purpose of this multicenter study was to (1) describe the incidence of meniscal entrapment and associated knee injuries in TSA and to (2) compare surgical and magnetic resonance image (MRI) findings for these injuries. Our hypothesis is that tibial spine injuries are not usually isolated injuries, and other meniscal, ligament, and cartilage injuries may be present. METHODS: MRI and surgical reports for patients with a diagnosis of a tibial spine fracture were retrospectively reviewed. Type of fracture was recorded as noted in the reports along with concomitant meniscal entrapment and osteochondral, ligamentous, and meniscal injury. Images and reports were reviewed by an orthopaedic surgeon at each respective institution. RESULTS: A total of 163 patients were included in this study. MRI was done for 77 patients and surgery was performed in 144 cases. Meniscal entrapment was found in 39.9% of all patients. MRI diagnosed meniscus, osteochondral, and non-anterior cruciate ligament ligamentous injury was found in 31.2%, 68.8%, and 32.4% of cases, respectively. Surgically diagnosed meniscus, chondral, and non-anterior cruciate ligament ligamentous injury was found in 34.7%, 33.3%, and 5.6% of patients, respectively. CONCLUSIONS: TSA fractures are associated with significant risk for concomitant knee injuries including meniscal tear, bone contusion, and chondral injury. Incidence of meniscal entrapment found during surgery was high, in spite of low incidence of positive findings by MRI. LEVEL OF EVIDENCE: Level IV-retrospective case series.

Anterolateral Ligament of the Knee Shows Variable Anatomy in Pediatric Specimens.

BACKGROUND: Anterior cruciate ligament (ACL) reconstruction failure rates are highest in youth athletes. The role of the anterolateral ligament in rotational knee stability is of increasing interest, and several centers are exploring combined ACL and anterolateral ligament reconstruction for these young patients. Literature on the anterolateral ligament of the knee is sparse in regard to the pediatric population. A single study on specimens younger than age 5 years demonstrated the presence of the anterolateral ligament in only one of eight specimens; therefore, much about the prevalence and anatomy of the anterolateral ligament in pediatric specimens remains unknown. QUESTIONS/PURPOSES: We sought to (1) investigate the presence or absence of the anterolateral ligament in prepubescent anatomic specimens; (2) describe the anatomic relationship of the anterolateral ligament to the lateral collateral ligament; and (3) describe the anatomic relationship between the anterolateral ligament and the physis. METHODS: Fourteen skeletally immature knee specimens (median age, 8 years; range, 7-11 years) were dissected (12 male, two female specimens). The posterolateral structures were identified in all specimens, including the lateral collateral ligament and popliteus tendon. The presence or absence of the anterolateral ligament was documented in each specimen, along with origin, insertion, and dimensions, when applicable. The relationship of the anterolateral ligament origin to the lateral collateral ligament origin was recorded. RESULTS: The anterolateral ligament was identified in nine of 14 specimens. The tibial attachment point was consistently located in the same region on the proximal tibia, between the fibular head and Gerdy's tubercle; however, the femoral origin of the anterolateral ligament showed considerable variation with respect to the lateral collateral ligament origin. The median femoral origin of the anterolateral ligament was 10 mm (first interquartile 6 mm, third interquartile 13) distal to the distal femoral physis, whereas its median insertion was 9 mm (first interquartile 5 mm, third interquartile 11 mm) proximal to the proximal tibial physis. CONCLUSIONS: The frequency of the anterolateral ligament in pediatric specimens we observed was much lower than other studies on adult specimens; future studies might further investigate the prevalence, development, and functional role of the anterolateral ligament of the knee. CLINICAL RELEVANCE: This study expands our understanding of the anterolateral ligament and provides important anatomic information to surgeons considering anterolateral ligament reconstruction concomitantly with primary or revision ACL reconstruction in pediatric athletes.

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.

Surgical Site Infection Reduction Program: Challenges and Opportunities.

Surgical site infections (SSIs) make up about 23% of hospital-acquired infections and may cost up to 10 billion dollars annually in direct medical expenses. St. Luke's Health System of Boise, Idaho implemented a committee to reduce its incidence of SSIs, focusing on the orthopaedic and neurosurgical departments. After identifying risk factors associated with patient medical comorbidities, operating room practices, and type of procedure, Project Zero recommended changes. The implementation of a preoperative clinic and protocol management of environmental and procedural factors reduced the hospitals rate by 50%. Project Zero continues to research best practices for clean room management and preventative care, striving to reach the overall goal of zero infections.