Arthroscopy of the knee in children

Current concepts of the management of anterior cruciate ligament injuries in children

Recent reports have suggested an increase in the number of anterior cruciate ligament (ACL) injuries in children, although their true incidence is unknown. The prognosis of the ACL-deficient knee in young active individuals is poor because of secondary meniscal tears, persistent instability and early-onset osteoarthritis. The aim of surgical reconstruction is to provide stability while avoiding physeal injury. Techniques of reconstruction include transphyseal, extraphyseal or partial physeal sparing procedures. In this paper we review the management of ACL tears in skeletally immature patients.

MRI findings in adolescent patients with acute traumatic knee hemarthrosis

BACKGROUND

Physical examination may be inconclusive in adolescents presenting with an acute traumatic knee effusion because of pain and guarding. The purpose of this study was to describe the magnetic resonance imaging (MRI) findings in adolescents with traumatic knee effusions and to compare injuries based on age, sex, and physeal maturity.

METHODS

All MRIs using a knee trauma protocol performed at our institution over a 2-year period were evaluated. One hundred thirty-one patients between the ages of 10 to 18 years of age with a clinical history of acute knee trauma and an effusion confirmed on MRI met our study inclusion criteria. They were divided into 2 age groups: 10 to 14 and 15 to 18 years old. Pathology was confirmed using clinical history, MRI, and any available surgical reports.

RESULTS

Of the 131 patients with an acute knee effusion, there were 59 patients in the younger group (10 to 14 y old) and 72 patients in the older group (15 to 18 y old). In the younger group, patellar dislocations (36%), anterior cruciate ligament (ACL) tears (22%), and isolated meniscus tears (15%) were the most common injuries. In the older group, ACL tears (40%), patellar dislocations (28%), and isolated meniscus tears (13%) were the most common injuries. ACL injuries represented 28% of injuries in males and 38% of injuries in females, whereas patellar dislocations represented 28% of injuries in males and 37% of injuries in females. There was a trend toward adolescents with active growth plates sustaining more patellar dislocations and adolescents with closed growth plates sustaining more ACL injuries. Forty-one percent of patients in this study underwent surgery.

CONCLUSIONS

Patellar dislocation is a common injury in children who present with a traumatic knee effusion, especially in young adolescents and females. Adolescents presenting with a traumatic knee effusion should undergo MRI because of the high rate of positive findings missed by physical examination and plain radiographs that may warrant surgical repair or reconstruction.

LEVEL OF EVIDENCE

Level III.

The assessment of usefulness of the qualification card and ultrasonographic consultation

The result of therapeutic success is always the effect of medical professionals cooperation. The creation of adequate mechanisms of cooperation of these teams demands time and appropriate examples. In the understanding of differentiated behaviors in the line patient – diagnostician – surgeon, particularly the mechanism of the cascade of errors formation, giving simple examples may help – their awareness will facilitate the formation of an adequate pattern of diagnostic-therapeutic chain. The therapeutic team formed in this way provides optimal forms of cooperation and positive result. One of the elements of the cooperation is the surgical procedure qualification card which is an example of the communication between surgeon and diagnostician. The propagation of proven examples seems to be justified by practical reasons. The introduction of the surgical procedure qualification card enabled maintaining of the preoperative and postoperative diagnoses in the range from 88.4% to 89.29%, the barrier of 90% however is still not achieved. The diagnoses discrepancy is still the most often occurring patient safety incident and our results should head towards its mineralization. In particularly complicated cases we come back to a well-known form of medical consultation, that is the form of examination and treatment establishment basing on simultaneous physical and ultrasound examination – hence the colloquial name of ultrasound consultation. The universality of medical consultation makes out of it an excellent tool, particularly in cases of significant discrepancy between physical and ultrasound examination. This is excellent form of the experience exchange and learning about mutual possibilities. We believe that the mechanisms presented will influence the improvement of patient security.

Effect of intra-articular pressurization associated with arthroscopy on the immature physis: investigation in an animal model

BACKGROUND

Despite the increased use of arthroscopy in pediatric orthopaedics, there is a paucity of data regarding the potential long-term effects of this procedure on the immature physis. The purpose of this study was to test the hypothesis that elevated intra-articular pressures used during arthroscopic surgery do not result in growth disturbances or morphologic alterations in the epiphyseal plate.

METHODS

Twenty-seven 6-week-old skeletally immature New Zealand white rabbits were divided into experimental (n=21) and control groups (n=6). In the experimental group, a hydraulic pump was used to pressurize 1 randomly assigned knee joint per rabbit to intra-articular pressures of 120 mm Hg for 2 hours. In the control group, rabbits received a sham intervention. All rabbits were killed at 6 months of age (skeletal maturity), and their tissues were evaluated grossly, radiographically, and histologically. Data collection included gross measurements (femur and tibia lengths, evaluation of varus/valgus angulation, and knee joint range of motion) and histologic analyses to determine whether morphologic changes were present in the articular cartilage or physis. Confidence intervals were used to test for statistical equivalence.

RESULTS

The pressurized and control groups had statistically equivalent gross measurements. No significant articular cartilage or physeal lesions were identified in histologic sections or radiographic studies.

CONCLUSION

This study provided no evidence that arthroscopic pressurization of the knee joint to 120 mm Hg for 2 hours significantly affected physeal growth in a skeletally immature rabbit model.

CLINICAL RELEVANCE

This study provides the first direct evidence that arthroscopic pressurization of immature joints has no clinically significant adverse long-term effects. Therefore, novel uses of arthroscopy in pediatric patients should be explored without undue concern with regard to premature physeal closure.

Anterior cruciate ligament injury in pediatric and adolescent soccer players: an analysis of insurance data

Injury claims from an insurance company specializing in soccer coverage were reviewed for a 5-year period. A total of 8215 injury claims (3340 females, 4875 males) were divided into three categories: (1) all injury, (2) knee injury, and (3) ACL injury. Knee injuries accounted for 22% of all injuries (30% female, 16% male). ACL injury claims represented 31% of total knee injury claims (37% female, 24% males). The youngest ACL injury was age 5. The ratio of knee injury/all injury increased with age. Compared with males, females demonstrated a higher ratio of knee injury/all injury and a higher ratio of ACL injury/all injury. This study demonstrates that ACL injury occurs in skeletally immature soccer players and that females appear to have an increased risk of ACL injury and knee injury compared with males, even in the skeletally immature. Future research related to ACL injury in females will need to consider skeletally immature patients.

Magnetic resonance imaging of the knee in children and adolescents. Its role in clinical decision-making

BACKGROUND

Recent studies have questioned the utility of magnetic resonance imaging in the diagnosis of pediatric knee disorders because of the morphologic changes during growth and the low accuracy of the formal interpretation of the magnetic resonance imaging scan by a radiologist. The purpose of this study was twofold: (1) to report the accuracy of formal interpretations of magnetic resonance imaging scans of the knee in children and adolescent patients by a radiologist, and (2) to determine the benefit, if any, of a personal review of the magnetic resonance imaging scan of the knee by the orthopaedic surgeon, as a routine part of the diagnostic evaluation.

METHODS

A three-year prospective study of all patients who underwent knee arthroscopy performed by a single surgeon, at two children's hospitals, was completed. The analysis focused on the six most common diagnoses: anterior cruciate ligament tear, lateral meniscal tear, medial meniscal tear, osteochondritis dissecans, discoid lateral meniscus, and osteochondral fracture. The preoperative diagnosis of the surgeon was determined by integrating the history and the findings on the clinical examination, plain radiographs, and magnetic resonance imaging scans (including the radiologist's interpretation).

RESULTS

Ninety-six patients with ninety-six abnormal knees were included. The mean age was 14.6 years at the time of surgery. Relative to operative findings, kappa values for the formal interpretations of the magnetic resonance imaging scans by a radiologist were 0.78 for an anterior cruciate ligament tear, 0.76 for a medial meniscal tear, 0.71 for a lateral meniscal tear, 0.70 for osteochondritis dissecans, 0.46 for discoid lateral meniscus, and 0.65 for osteochondral fracture. Relative to operative findings, kappa values for the preoperative diagnoses by the surgeon were 1.00 for an anterior cruciate ligament tear, 0.90 for a medial meniscal tear, 0.92 for a lateral meniscal tear, 0.93 for osteochondritis dissecans, 1.00 for discoid lateral meniscus, and 0.90 for osteochondral fracture. The preoperative diagnosis by the surgeon was better (p < 0.05) than the formal interpretation of the magnetic resonance imaging scans by the radiologist with respect to an anterior cruciate ligament tear, lateral meniscal tear, osteochondritis dissecans, and discoid lateral meniscus.

CONCLUSIONS

Integration of patient information with an orthopaedic surgeon's review of the magnetic resonance imaging scan of the knee in children and adolescent patients improves the identification of pathological disorders in four of the six categories evaluated. This study questions the necessity for and appropriateness of a routine interpretation of a magnetic resonance imaging scan of the knee in children and adolescents by a radiologist.

Fate of the anterior cruciate ligament-injured knee

Most patients with anterior cruciate ligament (ACL) injuries do well with activities of daily living even after follow-up in the range of 5 to 15 years. Most can participate in some sports activity if they are inclined to do so, but most will have some limitations in vigorous sports, and only a few will be entirely asymptomatic. The challenge to the clinician is to understand and predict how ACL deficiency in a given patient will affect that patients's life and activities. In counseling patients about treatment after an ACL injury, the clinician can use knee ligament arthrometry measurements and pre-injury sports activity to estimate the risk of injury over the next 5 to 10 years. Meniscus, chondral, and sub-chondral injuries are not uncommon, but rarely require surgical intervention in the early phase of ACL deficiency. The prevalence of clinically significant meniscal damage increases with time, and is associated with increasing disability, surgery, and arthrosis in high-risk patients. Ligament reconstruction has not been shown to prevent arthrosis, but in prospective studies it appears to reduce the risk of subsequent meniscal injury, improve passive anteroposterior knee motion limits, and facilitate return to high-level sporting activities.

Characteristic pattern and management of intra-articular knee lesions in different pediatric age groups

Posttraumatic hemarthrosis of the knee joint usually leads to arthroscopy. In a retrospective study we defined an age-specific spectrum of injuries and, subsequently, assigned an age-dependent diagnostic management for children up to 16 years. From January 1986 to December 1996, 1,273 patients up to 16 years of age with knee trauma presented to the emergency department. Overall, soft-tissue lesions prevailed (82%). Hemarthrosis occurred in only 18.0%. The patients were classified in three groups: group 1 (528 children younger than 10 years of age) with hemarthrosis in only 5.7% (mainly metaphyseal fractures and patellar dislocations), group 2 (207 preadolescents from 11 to 12 years of age) with hemarthrosis in 17.9% (patellar dislocations and fractures), and group 3 (538 adolescents between the age of 13 and 16 years) with hemarthrosis in 30.3% (main findings were intra-articular fractures and patellar dislocations, additionally, 16 ligamentous and two meniscal lesions). Correspondingly, physical examination, conventional radiography, and magnetic resonance imaging (most appropriate diagnostic tool for patellar dislocation) were sufficient to reveal injuries in children up to 13 years of age. Arthroscopy was predominantly justified in those older than 13 years of age, but only if it leads to therapeutic consequences.

Anterior cruciate injuries in the skeletally immature athlete: a review of treatment outcomes

The documentation of anterior cruciate ligament (ACL) injuries in the skeletally immature athlete has significantly increased over the past decade, primarily due to increased awareness of these injuries within this younger athletic population. The evaluation of these injuries are similar to that in the adult population. Diagnostic studies such as plain radiographs, as well as magnetic resonance imaging, can delineate the location of the ACL failure. Physical presentation most commonly includes an acute haemarthrosis and ligamentous insufficiency. Several studies have demonstrated that the diagnostic reliability of the physical examination is poor in children, especially in patients less than 12 years old. The site of ACL failure in this adolescent population is most commonly at the tibial insertion. We recommend arthroscopic or arthroscopically assisted open reduction and internal fixation with nonabsorbable sutures for all displaced tibial eminence fractures. Mid-substance ACL failures also occur in this athletic age group. The association of meniscal injuries with these ACL failures appears to be greater than 50%. Historically, poor subjective and objective outcomes have been associated with primary and extra-articular repairs. Intra-articular reconstruction is the gold standard. The issue of placing the graft across open physeal plates is under investigation. Recent animal studies as well as human clinical series have demonstrated safety in placing soft tissue, i.e. hamstring grafts, across open growth plates without subsequent angular or leg length discrepancy. Historically, non-operatively treated ACL failures are associated with poor functional outcomes as well as a high incidence of meniscal re-injury. If the treatment of an adolescent athlete with an ACL failure is to be rehabilitation until skeletal maturity, close follow-up is essential to detect functional instability, which may prompt earlier surgical reconstruction.

Knee arthroscopy in Chinese children and adolescents: an eight-year prospective study

In the period January 1985 to December 1992, 69 Chinese boys and 20 Chinese girls (average 14.6 years, age range 6 to 16 years) with a total of 92 involved knees underwent examination under anaesthesia and knee arthroscopy. Two thirds of the patients were engaged in sports activities. A haemarthrosis was present in 51 patients. In one patient, Staphylococcus aureus was shown, and in two children a serous-purulent aspirate grew Mycobacterium tuberculosis. The lateral meniscus was torn in four knees and the medial meniscus in six. An intact discoid lateral meniscus was found in five girls. Three partial anterior cruciate ligament (ACL) tears, three complete ACL tears and two posterior cruciate ligament tears were diagnosed. One child had an osteochondral defect of the lateral femoral condyle accompanying an ACL and a lateral meniscal tear. Nonspecific synovitis of unknown etiology was diagnosed in six patients who had presented subacutely with at least a 2-month history of a symptomatic monoarticular knee effusion with low grade local inflammation and no history of major trauma. The synovitis gradually resolved over a 6- to 10-month period after arthroscopy. Knee arthroscopy in children and adolescent patients is safe, gives a high diagnostic accuracy, and allows treatment of a variety of intraarticular conditions. This study also demonstrates that the range of intraarticular knee problems found in Chinese children and adolescents differs from that described in their Western counterparts.

[Diagnosis and therapy of cruciate ligament injuries in childhood. Clinical results]

In 19 years 21 children were operated upon anterior or posterior ligament ruptures. Follow-up based on policlinical data and 12 out of 21 patients were tested on follow-up (average follow-up time: 5.5 years). We made notes of the clinical data of an examination with the knee-arthrometer KT-1000 as well as of radiologic and sonographic methods. The subsequent scoring revealed mostly good to very good results. Still, in the long run it would be desirable to perform a prospective multicenter study to obtain statistically relevant data to give advice for ideal surgical treatment of ligamentous knee injuries in children.

Acute hemarthrosis of the knee in children

The purpose of this study was to determine the cause of acute hemarthrosis of the knee in a prospective pediatric patient population. Between December 1988 and August 1991, 21 consecutive children who were seen with an acute traumatic hemarthrosis of the knee had an arthroscopic evaluation. The average age of the children at the time of injury was 14 years, 3 months (range, 10 to 17 years). The mechanism of injury was a torsional strain to the knee in 12 (71%) of the 17 patients who could accurately remember the injury. The initial evaluation included a history, physical examination, and anteroposterior, lateral, sunrise, and comparison radiographs. The arthroscopic procedure was performed under general anesthesia, and the arthroscopic findings were compared with preoperative findings. During arthroscopic examination, an osteochondral fracture of the lateral femoral condyle or patella was identified in 14 (67%) of the 21 patients. Preoperative radiographs failed to identify the fracture in 5 (36%) of the 14 patients who had an osteochondral fracture. The anterior cruciate ligament was visualized and probed; an injury was found in only two cases (10%). We concluded that in children an acute traumatic hemarthrosis reflects a major injury to the knee. The children in this study had a high frequency of osteochondral fractures; ACL injuries were found in only two patients. Because of the unreliable nature of radiographic evaluation, arthroscopic evaluation is a valuable tool in differential diagnosis and treatment of acute hemarthrosis of the knee.

Patellar tendon graft reconstruction for midsubstance anterior cruciate ligament rupture in junior high school athletes. An algorithm for management

Between 1976 and 1988 we treated 75 junior high athletes who had midsubstance ruptures of the anterior cruciate ligament and open physes. Thirty-eight children were initially treated conservatively and later had an intraarticular patellar tendon graft reconstruction, 2 patients underwent extraarticular reconstruction and then later had a patellar tendon graft intraarticular reconstruction, and 20 children had a patellar tendon graft reconstruction initially. In all 60 patients the tibial and femoral tunnels were drilled through the open physes. Minimum followup was 2 years (mean, 4.2). Fifty-five of the 60 children were able to return to their original sports; 5 were active in less strenuous sports. No incidence of abnormal growth related to the intraarticular reconstructive surgery was recorded. Three children tore their anterior cruciate ligament grafts more than 2 years after surgery. Our records showed that conservative treatment of the active junior high athlete with an anterior cruciate ligament rupture failed in each case because of recurrent giving way or meniscal tears. Definitive treatment with an intraarticular autogenous patellar tendon graft reconstruction yielded good to excellent results and eliminated subsequent instability episodes and meniscal tears in our study group.

Arthroscopy of the acute traumatic knee in children. Prospective study of 138 cases

We performed diagnostic arthroscopy for acute knee trauma in 138 children and adolescents aged 13 (1-15) years. The compatibility between the clinical examination and the arthroscopic findings was 59 percent. Ligament injuries were found in 32 cases, 14 of which had rupture of the anterior cruciate ligament. The compatibility in the case of ligament injuries was 31 percent. 48 patients had dislocation of the patella, and a displaced osteochondral fragment was seen in 19, 14 of which were radiographically silent. In 37 cases of distortion of the knee a correct diagnosis would have been missed unless arthroscopy had been performed. Arthroscopy is therefore indicated in children with severe distortion of the knee, hemarthrosis and with dislocation of the patella.

The importance of arthroscopy in sports injuries in children and adolescents

Within a 3-year period (1985-1988), 60 children and adolescents with knee injuries sustained mainly while skiing or playing football (soccer) underwent clinical examination, X-radiography and arthroscopy. Nearly all the patients still had open epiphyseal plates in the knee region. Arthroscopy revealed more severe intra-articular trauma than had been suspected on the basis of clinical findings. The skiing injuries most commonly involved anterior cruciate ligament tears, whereas injuries of the patellar retinaculum and medial meniscus lesions predominated in soccer injuries. On comparison with arthroscopic diagnosis, clinical diagnosis was erroneous in about 45%. The most common mistaken clinical diagnosis was "medial meniscus tear". Of the 60 knee joints subjected to arthroscopy, 40 were severely enough injured to warrant surgery. Only one had normal intra-articular findings. The study demonstrates that children and adolescents can suffer knee trauma requiring surgery, despite open growth plates. Downhill skiing and soccer are particularly risky sports in this respect. Therefore, sports injuries involving haemarthrosis are clearly an indication for arthroscopy, even in childhood and adolescence. Arthroscopy enables early identification of the type and extent of intra-articular trauma and subsequent early initiation of appropriate therapy.

Arthroscopy in children

Arthroscopy was performed on the knees of 67 children aged 2-16 years with an overall clinical diagnostic accuracy of 45%. The most common clinical diagnoses were meniscal tear and patello-femoral pain and the accuracy of these diagnoses was 33% and 59% respectively. Diagnostic accuracy seemed unrelated to age. Arthroscopy led to definitive treatment which relieved symptoms in 21 (31%) of cases, revealed a diagnosis only in 43 (64%), and was non-contributory in 3 (4.5%). The procedure did not significantly help patients with patello-femoral pain.