ABSTRACT
Objective:To explore the diagnosis and treatment of posterior shoulder dislocation combined with reverse Hill-Sachs lesion.Methods:Two male patients were treated at Department of Joint Surgery, Affiliated Hospital of Qingdao University for posterior shoulder dislocation combined with reverse Hill-Sachs lesion from August to November 2022. Case 1 was a 46-year-old man, admitted 1 day after right should injury, and case 2 a 57-year-old man, admitted 2 days after right should injury. The injury was caused by electric shock in both, and their fractures were fresh with an injury area>50%. After anatomical reduction of the collapsed humeral head via the pectoralis major deltoid approach, an artificial bone was implanted and fixated with countersunk screws in both cases to reduce the shoulder joint. The Constant-Murley scale and visual analogue scale (VAS) were used to evaluate the functional recovery of the shoulder and pain after treatment.Results:No such perioperative complications as incision infection, brachial plexus injury or vascular injury was observed in either of the 2 patients. Reexamination 3 months after surgery showed in case 1: 110° of shoulder anterior flexion, 90° of shoulder abduction, 30° of external rotation (neutral position), 70° of internal rotation (neutral position), 70 points of Constant-Murley shoulder score, and 3 points of VAS pain score; in case 2: 130° of shoulder anterior flexion, 120° of shoulder abduction, 50° of external rotation (neutral position), 80° of internal rotation (neutral position), 70 points of Constant-Murley shoulder score, and 2 points of VAS pain score.Conclusion:For patients with posterior shoulder dislocation complicated with reverse Hill-Sachs lesion and humeral head collapse greater than 50%, open reduction and screw internal fixation combined with artificial bone grafting can achieve good short-term curative efficacy.
ABSTRACT
Objective:To understand and verify the biomechanical mechanism of tibial plateau Hoffa (coronal) fracture by simulating high-altitude falls and traffic injuries using knee joint specimens.Methods:Ten specimens of lower limb knee joint were used. They were from 6 males and 4 females, with an average age of 57.4 years (from 42 to 65 years). They were divided into 2 equal groups: one subjected to simulation of high-altitude falls (fall group) and the other to simulation of traffic injury (traffic injury group). After injury simulation, standard orthographic and lateral X-ray examinations and CT scans were performed of the knee joints in the extended position to observe whether there was a fracture, where the fracture occurred, and how the fracture line went.Results:A tibial plateau coronal fracture was successfully simulated in 6 cases, but not in the other 4 cases. The failure was attributed to femoral fractures and other types of tibial plateau fracture. In the 3 successful fractures simulated by high-altitude fall, the fracture line was located all on the posterior medial side, involving the posterior 1/3, 2/5, and 1/2 of the tibial plateau, respectively. The fracture line and the coronal plane formed angles of 21°, 19° and 12°, respectively. The fracture was not shown on X-ray film in one case which was a posterior medial fracture on CT. In the other 3 successful fractures simulated by traffic injury, the fracture line involved 1/6, 1/4 and 1/3 of the posterior tibial plateau, respectively. The angles between the fracture line and the coronal plane were 47°, 56° and 63°, respectively. One case showed no obvious fracture signs on the X-ray but a coronal fracture on CT.Conclusions:This study has confirmed for the first time that both high-altitude falls and traffic injuries can cause coronal fractures of the tibial plateau which vary significantly in the extent of involvement and morphology. X-rays are not sufficient to fully diagnose this type of fractures, suggesting that patients with a clear history of knee flexion or axial violence injury should be routinely scanned by CT to reduce risks of missed diagnosis and insufficient treatment.
ABSTRACT
Hoffa fracture of tibial plateau is a special type of coronal fracture of tibial plateau, among which occult fracture accounts for a large proportion, resulting in missing diagnosis and delayed treatment. The current studies are all case reports, and the incidence, diagnostic protocol, injury characteristics and injury mechanism of Hoffa fracture have not been systematically studied. The commonly used classifications such as AO type, Schatzker type, three-column classification and comprehensive classification of tibial plateau cannot cover this type. In this study, a retrospective case series study was performed for the clinical data of 3 086 patients with tibial plateau fractures. There were 13 patients with Hoffa fracture of tibial plateau, and 23% of them were occult ones. The injury mechanism of this fracture was as follows: under the state of knee joint flexion, axial violence through femur concentrated on the posterior half of tibial plateau, with the knee joint in transient varus and pronation position, leading to the posteromedial coronal splitting fracture. According to the position and degree of fracture displacement involving the joint, the fracture was divided into three type: type I involving the articular surface of tibial plateau fracture less than 1/4, type II involving the articular surface of tibial plateau equal to or more than 1/4 and less than 1/2, type III involving the joint face equal to or more than 1/2. Each fracture type was divided into three subtypes, of which subtype A was non-displaced fracture, subtype B had articular surface displacement<2 mm, and subtype C had articular surface displacement≥2 mm. According to the classification characteristics, the treatment principles were proposed. The authors systematically summarized the Hoffa fracture of tibial plateau for the first time in aspects of the incidence, injury characteristics, injury mechanism, fracture classification and treatment principles, which is helpful to avoid missed diagnosis and improve treatment efficacy.