Outcome of Single-Bundle Hamstring Anterior Cruciate Ligament Reconstruction Using the Anteromedial Versus the Transtibial Technique: A Systematic Review and Meta-analysis.

PURPOSE: To compare the clinical outcomes of single-bundle hamstring anterior cruciate ligament (ACL) reconstruction between the anteromedial (AM) and transtibial (TT) techniques. METHODS: We performed a comprehensive systematic review and meta-analysis of the English-language literature in the PubMed, Scopus, Web of Science, and Cochrane Central Register of Controlled Trials databases for articles that compared clinical outcomes of AM versus TT ACL reconstruction. The outcome measures analyzed included postoperative Lachman test, pivot-shift test, International Knee Documentation Committee (IKDC), and Lysholm scores. RESULTS: We included 10 articles from an initial 308 abstracts for the systematic review and included 6 studies for the meta-analysis. The study population consisted of a total of 733 patients, of whom 366 (49.9%) underwent the AM technique and 367 (50.1%) underwent the TT technique for ACL reconstruction. For postoperative knee stability, the AM technique yielded superior results in terms of the proportion of negative Lachman test results (n = 243; odds ratio [OR], 2.98 [95% confidence interval (CI), 1.29 to 6.88]) and proportion of negative pivot-shift test results (n = 238; OR, 3.67 [95% CI, 1.80 to 7.52]). For postoperative functional status, the AM technique yielded superior results in terms of objective IKDC grading (proportion with IKDC grade A) (n = 269; OR, 2.19 [95% CI, 1.23 to 3.88]) but had comparable Lysholm scores (n = 478; mean difference, 1.43 [95% CI, 0.01 to 2.84]). CONCLUSIONS: Single-bundle hamstring ACL reconstruction using the AM technique showed superior surgeon-recorded stability according to the IKDC knee score, Lachman test, and pivot-shift test. However, there was no difference in patient-reported functional outcome (Lysholm score). LEVEL OF EVIDENCE: Level III, systematic review and meta-analysis of Level I, II, and III studies.

Navigated total knee arthroplasty: is it error-free?

PURPOSE: The aim of this study was to determine whether errors do occur in navigated total knee arthroplasty (TKAs) and to study whether errors in bone resection or implantation contribute to these errors. METHODS: A series of 20 TKAs was studied using computer navigation. The coronal and sagittal alignments of the femoral and tibial cutting guides, the coronal and sagittal alignments of the final tibial implant and the coronal alignment of the final femoral implant were compared with that of the respective bone resections. To determine the post-implantation mechanical alignment of the limb, the coronal alignment of the femoral and tibial implants was combined. RESULTS: The median deviation between the femoral cutting guide and bone resection was 0° (range -0.5° to +0.5°) in the coronal plane and 1.0° (range -2.0° to +1.0°) in the sagittal plane. The median deviation between the tibial cutting guide and bone resection was 0.5° (range -1.0° to +1.5°) in the coronal plane and 1.0° (range -1.0° to +3.5°) in the sagittal plane. The median deviation between the femoral bone resection and the final implant was 0.25° (range -2.0° to 3.0°) in the coronal plane. The median deviation between the tibial bone resection and the final implant was 0.75° (range -3.0° to +1.5°) in the coronal plane and 1.75° (range -4.0° to +2.0°) in the sagittal plane. The median post-implantation mechanical alignment of the limb was 0.25° (range -3.0° to +2.0°). CONCLUSIONS: When navigation is used only to guide the positioning of the cutting jig, errors may arise in the manual, non-navigated steps of the procedure. Our study showed increased cutting errors in the sagittal plane for both the femur and the tibia, and following implantation, the greatest error was seen in the sagittal alignment of the tibial component. Computer navigation should be used not only to guide the positioning of the cutting jig, but also to check the bone resection and implant position during TKA. LEVEL OF EVIDENCE: IV.