Femoral radiographic landmarks for lateral collateral ligament reconstruction and repair: a new method of reference.

BACKGROUND: Little work has been made regarding the use of radiographic landmarks in fibular collateral ligament reconstruction. Radiographic tools can be of use to the surgeon in posterolateral reconstruction as secondary checks in the setting of tissue and bony attrition. HYPOTHESIS: Using standardized radiographic imaging, a zone for femoral tunnel placement in lateral collateral ligament (LCL) reconstruction can be identified. STUDY
DESIGN: Descriptive laboratory study.
METHODS: Eight fresh-frozen unmatched knees, free of any osseous or articular pathological changes, were selected for dissection (mean age, 61.3 years). Skin and surrounding soft tissues were left intact. Subsequent dissection was carried out to identify the true origin of the LCL. A radiographic marker was applied. True lateral radiographs of the distal femur (posterior condyles overlapping) were taken. Digital radiographic images were obtained and analyzed.
RESULTS: The Blumensaat line was found to be closely associated with the LCL origin on lateral radiographic imaging. On average, the LCL ligament was found to be 58% (+ or - 4.7%) across the width of the condyle and 2.3 mm (+ or - 2.3 mm) distal to the Blumensaat line. In all specimens, the anatomical LCL origin was found to have less than 5 mm variance from the mean.
CONCLUSION: The LCL origin is located within a specific region that is noted to have a small amount of variance. This is of benefit to the clinician in the traumatic and reconstructive setting where the true origin may not be easily identifiable through dissection. CLINICAL RELEVANCE: Intraoperative fluoroscopic imaging can be used as an adjunctive tool for femoral tunnel placement during posterolateral corner and LCL reconstruction.