Anterior Cruciate Ligament Injury at the Time of Anterior Tibial Spine Fracture in Young Patients: An Observational Cohort Study.

BACKGROUND: Anterior tibial spine fractures (ATSF) in the skeletally immature parallel anterior cruciate ligament (ACL) tears in adult patients, yet these injuries are generally regarded as mutually exclusive. Biomechanical analysis suggests that intrinsic ACL damage occurs during ATSF, and long-term clinical studies demonstrate residual anteroposterior knee laxity following ATSF. We aim to describe prevalence, demographics, and characteristics of pediatric patients who sustained ATSF with concomitant ACL injury. METHODS: We included 129 patients with ATSF over a 16-year period. Age, sex, injury mechanism, ATSF type, magnetic resonance imaging (MRI) evaluation, treatment modality, ACL injury, and concomitant meniscal/chondral injuries were analyzed. Concurrent ACL injury was confirmed either from MRI or intraoperatively. RESULTS: Nineteen percent (n=25) of ATSF patients had concomitant ACL injury, with ACL injury significantly more likely in type II or type III ATSF compared with type I ATSF (P=0.03). Patients with combined ATSF/ACL injury were significantly older (P=0.02) and more likely to be male (P=0.01). Mechanism of ATSF injury was not associated with ACL injury (P=0.83). Preoperative MRI had low sensitivity (0.09) for recognizing ACL injury at the time of ATSF relative to intraoperative assessment. Half of ATSF/ACL-injured patients had additional meniscal or chondral injury, with meniscal repair or debridement required in 37.5% of the type II ATSF/ACL injury. CONCLUSIONS: There are demographic characteristics, such as age (older) and sex (male), associated with a higher risk of concomitant ACL injury at the time of ATSF. Type II and type III ATSF patterns had a higher prevalence of ACL injury. MRI failed to correctly identify ACL injury at the time of ATSF. Concomitant ACL injury at the time of ATSF is highly prevalent in the skeletally immature, occurring in 19.4% of patients with ATSF. LEVEL OF EVIDENCE: Level IV-case series.

Epidemiology of Anterior Tibial Spine Fractures in Young Patients: A Retrospective Cohort Study of 122 Cases.

BACKGROUND: Historically, bicycle accidents were described as the most common mechanism for pediatric anterior tibial spine fractures (ATSFs). There is a paucity of current literature examining the demographic factors associated with these injuries. The purpose of this cohort study was to characterize the epidemiology of ATSFs presenting to a single tertiary referral pediatric hospital. METHODS: A consecutive cohort of 122 pediatric patients with ATSFs between 1996 and 2014 were reviewed. Radiographic variables, classification of fractures (Meyers and McKeever type), age, sex, height, weight, body mass index, and mechanism of injury were retrieved. Categories of mechanism of injury included organized sports (football, soccer, basketball, lacrosse, wrestling, and gymnastics), bicycling, outdoor sports (skiing, skateboarding, and sledding), fall, motor vehicle collision/pedestrian versus motor vehicle, and trampoline. RESULTS: Organized sports-related injuries represented the most common cause of ATSFs (36%). Other common mechanisms of injury included bicycle accidents (25%), outdoor sports (18%), and falls (11%). There was a higher proportion of males (69%) compared with females (31%). Males (mean age, 11.6 y) were significantly older than females (mean age, 9.8 y) (P=0.004). Younger patients (aged 11.5 y and below) were more likely to have displaced fractures (type III), whereas type I and type II were more common in patients above 11.5 years (P=0.02). Patients with fracture type I were significantly taller than patients with fracture type III. No other variables were found to differ significantly according to fracture severity, including sex, weight, and body mass index. CONCLUSIONS: To our knowledge, our study represents both the largest (n=122) and most up-to-date epidemiological ATSF study in pediatric patients. A higher rate of ATSF occurs due to organized sports rather than bicycling or motor vehicle collision. This 18-year data collection represents a change in the paradigm, and is likely multifactorial, including increased participation in youth sports and early sport specialization. LEVEL OF EVIDENCE: Level IV-retrospective, cohort study.

Gravity Fluid Flow More Accurately Reflects Joint Fluid Pressure Compared With Commercial Peristaltic Pump Systems in a Cadaveric Model.

PURPOSE: To evaluate intra-articular fluid pressures and joint compliance generated by fluid management systems on cadaveric shoulders and knees under simulated arthroscopic conditions, and to compare joint compliance between knee and shoulder specimens. METHODS: Intra-articular pressures of 5 cadaver shoulders and 5 knees were recorded for 4 arthroscopic pumps (Stryker FloControl, Stryker CrossFlow, Arthrex DualWave, DePuy Mitek FMS Duo) and a gravity feed system. Each specimen was tested 6 times with a pressure transducer for 2 minutes at 0, 25%, and 50% suction. The average pressures were analyzed with 1-way analysis of variance and Tukey's honestly significant difference tests (P < .05). RESULTS: At all suction levels, all pumps exhibited significantly greater pressure than gravity feed (P = .001 to P < .001). At both 25% and 50% suction, FloControl displayed significantly greater pressures (Pmax 160.44 mm Hg) than the other pumps or gravity feed (Pmax 46.9 mm Hg). CrossFlow had the lowest net percentage error (36.8%, 18.4 mm Hg) when compared with the standard pressure of 50 mm Hg, followed by gravity feed. All pumps had large initial overshoot (ie, Pinitial CrossFlow 99.4 mm Hg) followed by settling time, whereas gravity feed did not (Pinitial 55.2 mm Hg). CONCLUSIONS: Gravity feed is an accurate, reliable delivery method for arthroscopic fluid with minimal overshoot and lower intra-articular pressure ranges than commercial pump systems. There was no evidence of plastic deformation of the joint capsule, because capsular compliance increased linearly in both knee and shoulder specimens throughout testing within the established safe range of intra-articular pressures. CLINICAL RELEVANCE: Arthroscopic flow management systems produce maximal and overshoot pressures that are not seen with gravity flow. Surgeons should understand intra-articular pressure and fluid delivery behavior during shoulder and knee arthroscopy to adapt to the variability and higher maximal pressures when using pump systems. Maintaining appropriate pressure could prevent fluid extravasation and possible neuromuscular dysfunction.

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.

Return to Play Following Open Treatment of Femoroacetabular Impingement in Adolescent Athletes.

INTRODUCTION: After treatment of femoroacetabular impingement (FAI) in adolescent competitive athletes, the rate, timing, and level of return to play have not been well reported. METHODS: Adolescent athletes who underwent open FAI treatment were assessed at a minimum 1-year follow-up. Patients completed a self-reported questionnaire centered on the time and level of return to play. Pain and functional outcomes were assessed using the modified Harris Hip Score (mHHS) and the Hip Disability and Osteoarthritis Outcome Score (HOOS). RESULTS: Among the 24 athletes included, 21 (87.5%) (95% confidence interval [CI], 67.6% to 97.3%) successfully returned to play after open FAI treatment. The median time to return to play was 7 months (95% CI, 6 to 10 months). Of the 21 who returned to play, 19 (90%) returned at a level that was equivalent to or greater than their level of play before surgery. Three athletes (12.5%) did not return to play and indicated that failure to return to play was unrelated to their hip. There was significant improvement in the mHHS (P < 0.0001), HOOS (P < 0.0001), α angle (P < 0.0001), and offset (P < 0.0001). DISCUSSION: Most adolescent athletes can expect to return to the same or better level of sports participation during the first year after open treatment of FAI.

Delayed Anterior Cruciate Ligament Reconstruction in Young Patients With Previous Anterior Tibial Spine Fractures.

BACKGROUND: Avulsion fractures of the anterior tibial spine in young athletes are injuries similar to anterior cruciate ligament (ACL) injuries in adults. Sparse data exist on the association between anterior tibial spine fractures (ATSFs) and later ligamentous laxity or injuries leading to ACL reconstruction. PURPOSE: To better delineate the incidence of delayed instability or ACL ruptures requiring delayed ACL reconstruction in young patients with prior fractures of the tibial eminence. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: We identified 101 patients between January 1993 and January 2012 who sustained an ATSF and who met inclusion criteria for this study. All patients had been followed for at least 2 years after the initial injury and were included for analysis after completion of a questionnaire via direct contact, mail, and/or telephone. If patients underwent further surgical intervention and/or underwent later ACL reconstruction, clinical records and operative reports pertaining to these secondary interventions were obtained and reviewed. Differences between categorical variables were assessed using the Fisher exact test. The association between time to revision ACL surgery and fracture type was assessed by Kaplan-Meier plots. The association between need for revision ACL surgery and age, sex, and mechanism of surgery was assessed using logistic regression. RESULTS: Nineteen percent of all patients evaluated underwent delayed ACL reconstruction after a previous tibial spine fracture on the ipsilateral side. While there were a higher proportion of ACL reconstructions in type II fractures, there was not a statistically significant difference in the number of patients within each fracture group who went on to undergo later surgery (P = .29). Further, there was not a significant association between fracture type, sex, or mechanism of injury as it related to the progression to later ACL reconstruction. However, there was a significant association between age at the time of injury and progression to later ACL reconstruction (P = .02). For every year increase in age at the time of injury, the odds of going on to undergo delayed ACL reconstruction were greater by a factor of 1.3 (95% CI, 1.1-1.6). CONCLUSION: Although an ATSF is a relatively rare injury, our cohort of patients suggests that a subset of young patients with all types of tibial spine fractures will require later ACL reconstruction. There is a need to counsel patients that a delayed ACL rupture is a potential risk after an ATSF, especially as children approach skeletal maturity. Further patient follow-up and prospective studies are required.

Factors predictive of concomitant injuries among children and adolescents undergoing anterior cruciate ligament surgery.

BACKGROUND: The timing of treatment for pediatric anterior cruciate ligament (ACL) injuries remains controversial. The risks of delaying reconstruction and the differences between age groups are poorly defined. PURPOSE: To investigate factors that contribute to the prevalence and severity of concomitant chondral and meniscal injuries among patients aged 14 to 19 years versus those aged ≤14 years at the time of ACL reconstruction. The hypothesis was that concomitant injuries would be more prevalent in older versus younger subjects. Also, a delay in surgery would be predictive of the presence and severity of concomitant knee injuries requiring additional operative procedures. STUDY METHODS: Cohort study; Level of evidence, 3. METHODS: All subjects who underwent primary ACL reconstruction at a single tertiary pediatric hospital between 2005 and 2012 were retrospectively reviewed. The location, severity, and treatment of all concomitant knee injuries were recorded. Chi-square tests were used to compare the prevalence of chondral and meniscal injuries in the older (age, 14-19 years; n = 165) versus younger (age, ≤14 years; n = 66) cohorts. A multivariable logistic regression analysis was used to identify factors related to the presence of a concomitant injury that required additional treatment. Kaplan-Meier analyses were used to explore the relation between time to surgery and meniscal injury severity. RESULTS: There was a significant relationship between time to surgery and the development of an irreparable meniscal injury (P < .05 for all) in both the younger and older groups. Time to surgery correlated with severity of chondral injury in the younger cohort (P = .0343) but not in the older cohort (P = .8877). In the younger cohort, only a delay in surgery >3 months (odds ratio [OR] = 4.8; 95% CI, 1.7-14.4; P = .0027) was significantly predictive of the presence of an injury that required additional operative procedures. In the older patients, a return to activity before surgery (OR = 3.8; 95% CI, 1.52-11.9; P = .0034) and obesity (OR = 2.5; 95% CI, 1.1-7.4; P = .0381) were significantly predictive of an injury that required additional operative procedures. CONCLUSION: Compared with younger subjects, the prevalence of concomitant knee injuries as well as the need for additional operative procedures was greater among older subjects. A delay to surgery correlated with increased severity of injury among both older and younger populations. A delay in surgery >3 months was the strongest predictor of the development of a concomitant injury in the younger cohort. A return to activity and obesity were significantly related to the presence of a concomitant knee injury in the older cohort.

Delay to Reconstruction of the Adolescent Anterior Cruciate Ligament: The Socioeconomic Impact on Treatment.

BACKGROUND: A delay in pediatric and adolescent anterior cruciate ligament (ACL) reconstruction is associated with an increase in the number of concomitant meniscal and chondral injuries. Factors that contribute to this delay have not been well described. HYPOTHESIS: Socioeconomic and demographic factors are related to ACL surgery timing. STUDY METHODS: Cohort study; Level of evidence, 3. METHODS: All subjects who underwent primary ACL reconstruction at a single tertiary pediatric hospital between 2005 and 2012 were retrospectively reviewed. Variables included concomitant knee injuries (cartilage or meniscus injuries requiring additional operative treatment) and chronologic, demographic, and socioeconomic factors. Multivariable Cox proportional-hazards analyses were used to identify factors related to ACL surgery timing. RESULTS: The mean age of the 272 subjects was 15.2 ± 2.12 years. Time to surgery was significantly different among subjects who required multiple additional surgical procedures at time of ACL reconstruction (median, 3.3 months) compared with subjects with 1 (median, 2.0 months) or no additional injuries (median, 1.6 months). Subjects underwent ACL reconstruction significantly sooner if they were older at the time of injury (hazard ratio [HR], 1.2 per 1 year; 95% CI, 1.1-1.2; P < .0001) or were covered by a commercial insurance plan (HR, 2.0; 95% CI, 1.6-2.6; P < .0001). Median time to ACL surgery was 1.5 months (95% CI, 1.3-1.7) for subjects with commercial insurance plans compared with 3.0 months (95% CI, 2.3-3.3) for subjects with noncommercial insurance coverage. CONCLUSION: The risk of delayed ACL surgery was significantly higher among pediatric and adolescent subjects who were less affluent, who were covered by a noncommercial insurance plan, and who were younger. This study also confirms previous studies that have reported an association between a delay in ACL surgery and the presence of additional knee injuries requiring operative treatment, accentuating the importance of timely care. CLINICAL RELEVANCE: Access to care is a current area of research interest and health policy formation. Information in this arena drives 2 important aspects of health: most immediately, care provided to patients, and over a broader scope, the policy that directs health care. The orthopaedic surgeon should be aware of the association between socioeconomic and demographic factors and ACL surgery timing to optimize outcomes.

An epidermal inclusion cyst mimicking chronic prepatellar bursitis: a case report.

Soft tissue lesions are common to the prepatellar region, often due to acute or chronic trauma, and most frequently include prepatellar bursitis, lipomas, and ganglion cysts. We report a case of a posttraumatic prepatellar epidermal inclusion cyst to highlight the diagnostic complexities that can arise with soft tissue lesions in this location. On the basis of our case report, treating orthopaedic surgeons should consider the possibility of an epidermal inclusion cyst in patients who present with atypical anterior soft tissue masses with a history of trauma to the anterior knee.