Two Years Outcomes Of Total Hip Replacement Using A Short Stem With Femoral Neck Anchoring

Transcription

1 Two Years Outcomes Of Total Hip Replacement Using A Short Stem With Femoral Neck Anchoring Elias I. 1, Krieger M 1, Rinaldi G. 2, Christian L. 1, Mancini N. 2 1 Klinik Rotes Kreutz, Frankfurt Am Main, Germany 2 Niguarda Cà Grande Hospital, Milan, Italy

2 Background Today s patients are of a younger average age with a longer life expectancy and greater expectations of activity levels 1,2 To satisfy these higher demands bone conservation, versatile and efficient solutions are required Bone conservation is achieved both by preserving bone stock during resections and by optimizing the loading of the proximal femur to preserves bone from resorption in the future 1. Chidambaram R., Cobb A.G. Change in the age distribution of patients undergoing primary hip and knee replacement over 13 years an increase in the number of younger men having hip surgery, JBJS, 91(B), Issue SUPP I, Australian Orthopaedics National Joint Registry, 2008

3 Background Neck cut in antero-posterior to improve Range of Motion and fatigue strength Reduced implant neck length to avoid leg lenght discrepancies Optimum fit and fill of the neck resection for a maximal primary fixation Distal tip is polished and rounded to minimize localized stress regions which can lead to thigh pain and to avoid cortical perforation Medial radius to optimize physiological load distribution in the proximal femur from 100mm to 140mm: iincreasing with size

4 Materials & Methods Objective Evaluation of clinical and radiographic outcomes after THA using a short stem Chirurgie Orthopädie Rhein-Main-Germany Manfred Krieger, MD Patients 267 patients (271 hips) enrolled into 2 study sites Study phase Average FU: 27 months Maximum FU: 48 months Niguarda Ca Grande -Milano-Italia Giampaolo Rinaldi, MD

5 Materials & Methods Outcomes Clinical: Harris Hip Score & Range of Motion Radiographic: Biological bone responses (eg. patterns of osteointegration, metaphyseal bone alterations, stress-shielding, radiolucent lines, calcar resorption) Change of implant position Subsidence Heterotopic ossifications Loosening Modified Gruen Zones 3 3 Gruen TA, McNeice GM, Amstutz HC."Modes of failure" of cemented stem-type femoral components: a radiographic analysis of loosening. Clin Orthop Relat Res Jun;(141):17-27.

6 Materials & Methods Patient population Demographics Gender Male 134 (49.5%) Females 137 (50.5%) Age 62.4± 10.9 (26-90) yrs Anthropometrics Height 170.2± 9.4 ( ) cm Weight 80.2 ± 16.3 (50-150) Kg BMI 27.6± 4.7 ( ) Kg/cm 2 Data are reported as No. (%) or Average± St. Dev. (Min.-Max.)

7 Materials & Methods Preoperative data Diagnosis 90.7% Primary coxarthrosis DDH (Crowe I) Osteonecrosis Coxa magna 1.6% 1.6% 3.6% 1.6% 0.4% 0.4% Secondary coxarthrosis DDH (Crowe II) Perthes disease Side affected Left 125 (47.1%) Right 146 (52.9%) Type of surgery Primary 270 (99.6%) Revision 1 (0.4%) Data are reported as No. (%)

8 Implants (%) Stem size distribution #1 #2 #3 #4 #5 #6 #7 #8 #9 Couplings Stem size 35; 13% Surgical Approach Materials & Methods Intraoperative data Lateral Watson-Jones 201 (74.2%) Postero-lateral 70 (25.8%) Anesthesia spinal 271 (100%) Surgery time 56.3± 18.5 Data are reported as No. (%) or Average± St. Dev. (Min.-Max.) 222; 83% 10; 4% 1; 0% Ceramic-on-Ceramic Metal-on-Metal UHMWPE-on-Ceramic UHMWPE-on-Metal

9 HHS Average (points) Range of Motion degrees ( ) Results Clinical outcomes Harris Hip Score Range of Motion Preop 1 month 6 months 12 months 24 months Time points 0 Preop Flexion 1 month 6 months 12 months 24 months Time points Abduction External rotation Adduction Internal rotation

10 Results Radiographic outcomes Trabeculae of the proximal methaphysis reoriented according to increased compressive loads Diaphyseal cortical remodelling without hyperthrophy and development of cancellous bone Visible osteointegration patterns in 100% cases already at 6 weeks postoperatively No stress shielding No progressive radiolucent line at bone-stem interface No loosening, no mechanical failure

11 Conclusion Good clinical outcomes already at 1 month after surgey Excellent radiographic outcomes with all positive signs of bone remodelling suggesting an optimal load transfer and good osteointegration already after 6 weeks after surgery Preservation of the diaphyseal cortical bone delivering an almost untouched femoral diaphysis for an easy and conservative revision surgery

12 The early clinical experience with COLLO-MIS is very satisfactory. First follow-up results are really promising. G. Rinaldi, MD Ospedale Niguarda Cà Granda, Milan, Italy Faster rehabilitation thanks to an optimal primary fixation and a minimally invasive surgical technique. M. Krieger, MD Gelenkzentrum Rhein-Main, Wiesbaden, Germany