Mechanical evaluation of tibial fixation of the hamstring tendon in anterior cruciate ligament double-bundle reconstruction with and without interference screws

OBJECTIVE: The objective of this study was to compare two postero-lateral bundle (PLB) tibial fixation techniques for the reconstruction of the anterior cruciate ligament with double bundle: a technique without the use of an interference screw, preserving the native tibial insertion of the tendons of the gracilis and semitendineous muscles, and a technique with the use of an interference screw and without preserving the insertion of the tendons. METHODS: A comparative study was conducted in cadavers with a universal mechanical test machine. In total, 23 cadaver knees were randomized for tibial fixation of the PLB using the two techniques: Maintaining the tibial insertion of the tendons during reconstruction, without the use of an interference screw (group A, 11 cases); and fixating the graft with an interference screw, without maintaining the insertion of the tendons (group B, 12 cases). A continuous traction was performed (20 mm/min) in the same direction as the produced tunnel, and force (N), elongation (mm), rigidity (N/mm), and tension (N/mm2) were objectively determined in each group. RESULTS: Group A exhibited a maximum force (MF) of 315.4±124.7 N; maximum tension of 13.57±3.65 N/mm2; maximum elongation of 19.73±4.76 mm; force at the limit of proportionality (FLP) of 240.6±144.0 N; and an elongation at the limit of proportionality of 14.37±6.58 mm. Group B exhibited a MF of 195.7±71.8 N; maximum tension of 8.8±3.81 N/mm2; maximum elongation of 15.3±10.73 mm; FLP of 150.1±68.7 N; and an elongation at the limit of proportionality of 6.86±2.42 mm. When comparing the two groups, significant differences were observed in the variables of maximum force (p=0.016), maximum tension (p=0.019), maximum elongation (p=0.007), and elongation at the limit of proportionality (p=0.003). CONCLUSION: The use of the native insertion of the semitendineous and gracilis tendons, without an additional fixation device, presented mechanical superiority over their fixation with interference screws.

Resultado do tratamento cirúrgico da tríade terrível do cotovelo / Result from surgical treatment on the terrible triad of the elbow

Avaliar os resultados do tratamento cirúrgico da tríade terrível do cotovelo, com no mínimo seis meses de seguimento, considerando a função do cotovelo. MÉTODOS: Foram analisados os seguintes aspectos de 20 pacientes submetidos a tratamento cirúrgico por tríade terrível do cotovelo: escores Dash (Disabilities of the Arm, Shoulder and Hand), Meps (Mayo Elbow Performance Score), dor pela EVA (Escala Visual Analógica), ADM (arco de movimento), satisfação do paciente, grau de energia do trauma, complicações e radiografias. RESULTADOS: O tempo médio de seguimento dos pacientes foi de 38 meses. Houve relação estatisticamente significativa entre: mecanismo de trauma e satisfação dos pacientes; desfecho radiológico "ossificação heterotópica" e satisfação; ADM funcional de flexo-extensão e satisfação e entre o tipo de fratura da cabeça do rádio e a presença de desfecho radiológico. CONCLUSÃO: O tratamento cirúrgico da tríade terrível do cotovelo proporcionou, de forma geral, resultados satisfatórios, quando se considera a função dessa articulação no retorno às atividades.

To evaluate the results from surgical treatment of the terrible triad of the elbow, with a minimum of six months of follow-up, taking elbow function into consideration. METHODS: The analyzed aspects of 20 patients, who underwent surgical treatment of the terrible triad of the elbow, were given as follows: Dash score (Disabilities of the Arm, Shoulder and Hand), Meps (Mayo Elbow Performance Score), pain according to VAS (visual analog scale), ROM (range of motion), patient satisfaction, degree of energy of the trauma, complications and radiographs. RESULTS: The mean length of follow-up among the patients was 38 months. There were statistically significant relationships between the following set of parameters: trauma mechanism and patient satisfaction; radiological outcome of "heterotopic ossification" and satisfaction; functional flexion-extension ROM and satisfaction; and between type of radial head fracture and presence of a radiological outcome. CONCLUSION: The surgical treatment for the terrible triad of the elbow generally provided satisfactory results, when the functioning of this joint upon the return to activities was taken into consideration.