A Rare Hoffa Fracture with Sagittal Split and Intra-articular Comminution: A Case Report and Literature Review.

Introduction: A Hoffa fracture is a rare coronal plane, intra-articular fracture of the femoral condyle involving the weight-bearing portion of the posterior distal femur. The anatomy of this fracture lends it to be an inherently unstable injury, requiring surgical fixation to achieve stability. To date, research describing Hoffa fractures is limited to small case series and case reports. This article aims to describe the first case discussion of a unique type of Hoffa fracture with a sagittal split within the fragment and intra-articular comminution. We review the etiology, management, and follow-up of this case with respect to the existing literature. Case Presentation: A 40-year-old man involved in a high-speed motorcycle collision presented with a displaced coronal plane, intra-articular fracture of the lateral femoral condyle (Hoffa fracture). Cross-sectional imaging with MRI identified a sagittal split in the Hoffa fragment and partial anterior cruciate ligament rupture. This was managed with open reduction and internal fixation (ORIF) through a lateral parapatellar approach with cannulated compression screws and a distal radius plate used in buttress mode. Postoperatively, the patient was rehabilitated with graduated increase in range of knee movement range of motion (ROM) and weight-bearing. Five months after surgery, he had regained independent motion of the knee but suffered residual stiffness, which required arthroscopic adhesiolysis. At 6-month follow-up, the patient was pain free and had resumed normal activities with knee ROM 5-90°. Conclusion: This article highlights a unique and rare subtype of Hoffa fracture not illustrated in current classifications. Management is notoriously challenging with little consensus as to the optimal approach, implants, and post-operative rehabilitation. ORIF provides the best choice for maximal post-operative knee function. In our case, a buttress plate was utilized to stabilize the sagittal fracture component. Post-operative rehabilitation may be complicated by soft-tissue and/or ligamentous injury. Choice of approach, technique, implant, and rehabilitation are dependent on fracture morphology. Close follow-up is required with strict physiotherapy to ensure sufficient long-term range of movement, patient satisfaction, and return to activity.