Deep venous thrombosis and pulmonary embolism after anterior cruciate ligament reconstruction: incidence, outcome, and risk factors.

AIMS: The aim of this study was to investigate the incidence, risk factors, and outcome of venous thromboembolism (VTE) following anterior cruciate ligament (ACL) reconstruction in a nationwide cohort. PATIENTS AND METHODS: All ACL reconstructions, primary and revision, that were recorded in the Swedish Knee Ligament Register (SKLR) between 2006 and 2013 were linked with data from the Swedish National Board of Health and Welfare. The incidence of VTE was determined by entries between the day of surgery until 90 days postoperatively based on diagnosis codes and the prescription of anticoagulants. Risk factors, outcome, and the use of thromboprophylaxis were analyzed. Descriptive statistics with multivariate analysis were used to describe the findings. RESULTS: The cohort consisted of 26 014 primary and revision ACL reconstructions. There were 89 deep venous thromboses (DVTs) and 12 pulmonary emboli (PEs) with a total of 95 VTEs (0.4 %). Six patients with a PE had a simultaneous DVT. The only independent risk factor for VTE was age greater than or equal to 40 years (odds ratio 2.31, 95% confidence interval 1.45 to 3.70; p < 0.001). Thromboprophylaxis was prescribed to 9461 patients (36%) and was equally distributed between those with and those without a VTE (37.9% vs 36.4%). All patient-reported outcome measures (PROMs) one and two years postoperatively were significantly lower in those with VTE. CONCLUSION: The incidence of VTE following ACL reconstruction is 0.4%, and the only significant risk factor is age. Patients with VTE had worse postoperative clinical outcome than patients without VTE. We recommend against the routine use of thromboprophylaxis, but it should be considered in older patients.

Growth influences knee laxity after anterior tibial spine fracture: a study on rabbits.

An anterior tibial spine (ATS) fracture, with or without displacement, was created in the right knee of 8-week and 22-23-week-old rabbits. After 4 weeks of cast immobilization and 8 weeks of free cage activities, the animals were killed. A method to measure anterior knee laxity in rabbits was developed using a material testing machine. The laxity of the right knee was compared to the unoperated left knee in each rabbit. The difference was found to have increased in the adult rabbits after the healing of a displaced ATS fracture (median 0.5 mm, range 0.3-0.9), but not in the young rabbits (median 0.2 mm, range 0.0 -0.4). The ultimate load of the anterior cruciate ligament (ACL) was reduced after healing of the ATS fracture. The results support the theory that further growth may compensate for the functional elongation of the ACL caused by healing of a displaced ATS fracture. The study also indicates that an ATS fracture may affect the mechanical properties of the ACL.

Home traction of femoral shaft fractures in younger children.

The study describes a home traction program of femoral shaft fractures in preschool children using the 90-90 traction technique. A special bed stretcher was designed for the program and adapted for use in ordinary ambulances and in all types of homes. Twenty-four patients, 2.2-5.9 years of age, were followed. The average hospital stay was 7.0 days, and the average home traction period was 22.1 days. One patient had a superficial pin tract infection. The treatment was uneventful in all other cases. All fractures healed with a shortening of < or = 1 cm. The angulation was < or = 10 degrees in all cases but one, which healed with a valgus angulation of 15 degrees but without functional disability. Interviews showed that the parents were very satisfied with the treatment program. The cost savings are obvious compared to traction treatment in the hospital.

The influence of transphyseal drilling and tendon grafting on bone growth: an experimental study in the rabbit.

The undulating area of the distal femoral physis has been measured in New Zealand White rabbits, by using an image analyzer in histologic sections, and correlated to radiographic measurements. The relative size of a physeal drill injury necessary to cause growth disturbance has been found to be 7-9%. A transphyseally placed tendon, even as a free graft, prevented solid bone-bridge formation in the drill hole and growth disturbance. The results are of possible clinical significance.

Osteochondral lesions in the radiocapitellar joint in the skeletally immature: radiographic, MRI, and arthroscopic findings in 13 consecutive cases.

Radiography, magnetic resonance imaging (MRI), and arthroscopy were performed in 13 consecutive cases of osteochondral lesions of the radiocapitellar joint in 12 patients aged 11-16 years. Nine patients had a high activity level, and two patients had a significant trauma before the onset of symptoms. Symptoms were limited range of motion, pain, and catchings or lockings. Clinical findings were decreased range of motion and lateral elbow tenderness. Radiography revealed loose body, flattening of the humeral capitellum, or subchondral cysts (or a combination of these) in all cases but three. There was a good correlation between MRI and arthroscopic examination. Nine lesions were located in the humeral capitellum, one lesion in the radial head, and in three cases, lesions were found in both sites. Loose-body removal, shaving, or subchondral drilling (or a combination of these) was performed in 11 cases. All surgically treated patients improved in the short run. Awareness of the typical clinical and radiologic picture will allow identification of the cases suitable for arthroscopy and surgical treatment. In these cases, MRI can be omitted.

Anterior cruciate ligament injuries in skeletally immature patients.

Twenty-eight consecutive, skeletally immature patients (9.9-15.0 years of age at the time of injury) with total rupture of the anterior cruciate ligament (ACL) were followed up for 3-5 years. The aims of the study were to monitor the natural course of conservative treatment, to identify variables relevant to failure of conservative treatment, and to evaluate an over-the-top procedure for ACL reconstruction by using the semitendinosus tendon and avoiding the physes. The patients were interviewed according to Lysholm knee score and Tegner activity level. Knee laxity and muscle torque were measured. Five patients insisted on immediate reconstruction. Twenty-three patients were sent to a 3-month rehabilitation program. Sixty-eight percent of the patients, who made an attempt with conservative treatment, had been operated on at follow-up. The patients not operated on were younger at injury and had a lower activity level at follow-up. The surgical procedure improved objective and subjective knee function, but there was a correlation between high activity level and a low Lysholm score.

Long-term follow-up of anterior tibial spine fractures in children.

In a long-term follow-up (mean 16 years) of 61 children with anterior tibial spine fractures, subjective knee function (Lysholm score) was excellent or good in 87% of the subjects and fair in 13%. Eleven percent of the children had a lower activity level (Tegner score) than desired. Muscle performance was affected in those subjects with the lowest Lysholm scores. Pathological knee laxity was found in 38% of the subjects, but was not reflected in poor subjective knee function. Age at injury did not influence the outcome. There was no indication that young children can eliminate slackness of the anterior cruciate ligament by further growth. Only in type III fractures was there a correlation between fracture displacement after healing and knee laxity, as well as between knee laxity and Lysholm score. Arthroscopy-guided or open reduction and internal fixation seems to be a worthwhile procedure only in dislocated type III fractures.

Internal fixation with biodegradable rods in pediatric fractures: one-year follow-up of fifty patients.

Fifty children with transphyseal or osteochondral fractures were treated with biodegradable osteosynthesis material and followed for at least 1 year. All 50 fractures healed, and there were no major complications; 11 of them were fractures of the radial humeral condyle. In a prospective randomized study, they were compared with metal pin fixation of the same fracture (eight cases). No major differences were noted. After the study was completed, we observed two cases of nonunion of intraarticular fractures of the radial head, probably related to foreign body reaction to the resorbable implant material. Biodegradable osteosynthesis material is advantageous in treatment of children's fractures because it makes a removal operation unnecessary. It is ideal in cases of osteochondral fractures. Further experience with this material is necessary, however, before it can be safely recommended.