Introduction and Objectives: Sinding-Larsen-Johansson (SLJ) syndrome is a frequent entity in which there is pain on the anterior aspect of the patella in young athletes. Its etiopathogenesis is not well defined and it is considered a traction apophysitis. Our objective was to analyze the association of SLJ syndrome with the presentation of elevated patella.

Materials and Methods: We carried out a prospective study of 15 knees with evident clinical and radiological signs of SLJ syndrome and another 15 knees without any previous pathological condition. We used X-rays to measure the Caton-Deschamps index, the modified Insall index, and the posterior angle of inclination of the proximal surface of the tibia; we also took clinical measurements of the popliteal angle.

Results: We studied 15 knees in 14 patients. The percentage of males was 85.7% and the mean age of appearance of this pathological condition was 10.86 years (+/− 1.61) Analysis of the data shows that there were no significant differences (p> 0.5) between the groups in relation to the Caton index and the modified Insall index. In relation to the measurements of the popliteal angle of damaged knees, we did find significant differences (mean value: 32.50 d.t.:8.90) with reference to the control group (mean value: 17.67 (+/−. 8.21), and the same was true for the measurements of the posterior inclination angle (mean value: 10.47 (+/− 2.82) in comparison with the knees of the control cases (mean value: 8.33 (+/− 1,40).

Discussion and Conclusions: In conclusion, we found a statistically significant relationship between SLJ syndrome and shortening of the hamstring and increase in the posterior angle of inclination of the tibia.

We have studied the medium- and long-term effects of femoral intramedullary nailing in 34 children. There was a high incidence of abnormality at the proximal end of the femur, including coxa valga, arrest of growth of the greater trochanter and thinning of the neck of the femur, because of damage to the trochanterocervical growth plate. These disorders affected 30% of the patients, mostly under the age of 13 years (p < 0.05), and were seen more frequently when the nail had been introduced through the piriform fossa. Other factors, such as the side, gender, aetiology, proximal or retrograde insertion, the size of nail and removal of the implant did not influence the result. We recommend that in patients under the age of 13 years other methods of management should be used to avoid damage to the growth plate.