Preoperative patient and injury factors of successful rehabilitation after anterior cruciate ligament reconstruction with single-bundle techniques.

PURPOSE: The aim of this systematic review was to determine which patient determinants and injury factors, before anterior cruciate ligament reconstruction by arthroscopic single-bundle techniques, affect postoperative rehabilitation.

METHODS: A search of PubMed, Embase, and the Cochrane Database of Clinical Trials was performed up to February 2013. After application of our inclusion criteria, a final selection was made based on studies' methodologic score assessed with the Newcastle-Ottawa Scale. Meta-analysis was planned for each prognostic factor when data were considered clinically and statistically homogeneous.

RESULTS: Meta-analysis showed that male patients have better functional outcomes. Qualitative synthesis from 18 high-quality studies showed that patients operated on before 30 years of age reach higher activity levels. Patients with high baseline body mass index have lower activity levels after surgery. Smoking results in more symptoms and lower activity levels and subjective scores. Reconstruction before 3 months results in higher activity levels. Preoperatively, a less than 20% quadriceps strength difference, 50° of tibial external rotation or less, absence of flexion deficits, low knee influence on the patient's activity level, and less anterior knee pain result in higher functional scores. Preoperative anterior laxity difference does not predict functional scores. The prognostic value of preoperative activity and competition level for postoperative functional outcome is controversial. Patients with concomitant meniscal injuries have worse functional outcomes. The prognostic value of concomitant chondral pathology for postoperative functional outcome is controversial. Collateral ligament injury could predict functional scores or activity level.

CONCLUSIONS: Male gender, patient age younger than 30 years, reconstruction before 3 months, and high baseline activity level contribute to better functional outcomes. Smoking, high body mass index, quadriceps strength, and range-of-motion deficits affect rehabilitation negatively. Preoperative anterior laxity does not influence rehabilitation. The role of preoperative prognostic injury factors remains unclear because of limited evidence.

LEVEL OF EVIDENCE: Level III, systematic review of Level II and III studies.