Superior Compressive Strength of a Calcaneal Fracture Construct Augmented with Remodelable Cancellous Bone Cement

• Published in: Journal of bone and joint surgery. American volume Vol. 81; no. 2; pp. 239 - 246
• Main Authors: THORDARSON, DAVID B, HEDMAN, THOMAS P, YETKINLER, DURAN N, ESKANDER, ENASS, LAWRENCE, T N, POSER, ROBERT D
• Format: Journal Article
• Language: English
• Published: Boston, MA Copyright by The Journal of Bone and Joint Surgery, Incorporated 01.02.1999; Journal of Bone and Joint Surgery Incorporated; Journal of Bone and Joint Surgery AMERICAN VOLUME
• Edition: American volume
• Subjects: Biological and medical sciences; Bone Cements; Bone Plates; Bone Screws; Cadaver; Calcaneus - diagnostic imaging; Calcaneus - injuries; Calcaneus - physiopathology; Calcaneus - surgery; Calcium Phosphates; Fracture Fixation, Internal - methods; Fractures, Bone - diagnostic imaging; Fractures, Bone - physiopathology; Fractures, Bone - surgery; Humans; Medical sciences; Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases; Technology. Biomaterials. Equipments; Tomography, X-Ray Computed; Human; Diseases of the osteoarticular system; Lower limb; Exploration; Fracture; Compressive strength; Trauma; Calcaneum; In vitro; Biomechanics; Orthopedic surgery; Fixation; Disease of the foot; Cement; Spongious bone; Bone; Technique
• ISSN: 0021-9355; 1535-1386
• DOI: 10.2106/00004623-199902000-00011

Twenty-six paired, fresh-frozen cadaveric feet were disarticulated at the ankle joint, and the dome of the talus was potted. Stress-risers were placed along the medial, lateral, and posterior aspects of the calcaneus, and the specimen was loaded rapidly to failure in a testing machine to produce a type-IIB displaced intra-articular fracture according to the classification system of Sanders et al. One specimen of each pair was treated with standard internal fixation with bone-grafting (the control group), and the other was treated with similar fixation but with SRS (Skeletal Repair System) calcium phosphate bone cement placed in any osseous defect. All of the specimens were cured for twenty-four hours in a bath of saline solution at 37 degrees Celsius. The specimens were tested cyclically for ten cycles from zero to 100 newtons at one hertz and for 1010 cycles from zero to 350 newtons at one hertz. The deformation per cycle (millimeters per cycle), first-cycle deformation (millimeters), number of cycles to failure, and number of specimens withstanding the cyclical testing were calculated. The specimens were examined radiographically before and after fracture and after reconstruction and testing. A large difference in the results of the cyclical testing was noted. The specimens that had been augmented with the SRS bone cement had an average deformation of 0.00195 millimeter per cycle compared with 1.013 millimeters per cycle in the control group (p < 0.005). A similar magnitude of difference was noted when the results were stratified for good and poor-quality bone. Visual examination and radiographs demonstrated that a type-IIB displaced intra-articular fracture had been created reproducibly, and computed tomographic scans showed that nearly anatomical reconstruction had been achieved in all of the specimens. The computerized tomographic scans revealed good filling of the osseous voids and no evidence of failure of the cement after cyclical loading. CLINICAL RELEVANCEWe noted a large increase in the stability and compressive strength of the fixation of the calcaneal fracture constructs that had been augmented with the SRS bone cement. Clinical use of this new bone cement could considerably increase the initial strength of the fracture construct, which could lead to more rapid rehabilitation after this difficult fracture. In addition, the bone cement may obviate the need for autogenous bone-grafting.