Dysplasia Coxarthrosis, Post-traumatic Necrosis of the Femoral Head, Primary and Secondary Coxarthrosis
Conditions
Keywords
Nanos, THA, MBRSA
Brief summary
The primary purpose of this study was to evaluate the implant fixation of the NANOS™ Neck Preserving Hip Stem (OHST Medizintechnik AG, distributed by Smith & Nephew GmbH, Marl, Germany) by measuring the migration of the implant using the model-based roentgen stereophotogrammetric analysis (MBRSA).
Interventions
DEVICETotal Hip Arthroplasty
Sponsors
Smith & Nephew Orthopaedics AG
Study design
Observational model
COHORT
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
30 Years to 65 Years
Healthy volunteers
No
Inclusion criteria
* Subject required primary total hip arthroplasty unilateral or bilateral with a diagnosis of primary and secondary coxarthrosis, dysplasia coxarthrosis and post-traumatic necrosis of the femoral head confirmed by x-ray analysis. For bilateral subjects at least three months between surgical procedures were required. * Subject was willing to consent to participate in the study and planned to be available for the follow-up examinations. * Subject had normal motor function of the lower extremities, documented through clinical examinations and lack of signs of a neurological disease with changed motor function. * Subject was 30 to 65 (inclusive) years of age at time of surgery.
Exclusion criteria
* Subject had previous bone or soft tissue surgery of the affected hip except for arthroscopic surgery. * Subject had a local or systemic infection. * Subject had previously diagnosed osteoporosis. * Subject had a femoral neck angle of \>145°. * Subject had a femoral neck angle of \<125°. * Subject had a disease of the cardiovascular system involving particularly reduced load capacity in the everyday life, counting as contraindication of physical stress (American Society of Anaesthesiologists' (ASA) Score 3 or 4). * Subject had a documented allergy against elements of the implanted device. * Subject had a neurological disease with changed motor function. * Subject was pregnant. * Subject had a Body Mass Index (BMI) \> 30. * Subject suffered from alcoholism or addictive disorders. * Subject needed a revision hip arthroplasty. * Subject had an insufficient command of the language to understand patient information and consent.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Evaluation of migration pattern of the Nanos stem | 2 years | Measuring migration used the model-based RSA method |
| Change in quality of life | 2 years | Measuring change in quality of life using the Short Form (SF) 36 Mental Component Score * Minimum Value: 0 (worst outcome) * Maximum Value: 100 (best outcome) |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Harris Hip Score | 2 years | Investigator assessed outcome score Minimum: 0 (worst outcome) Maximum: 100 (best outcome) |
| University of California, Los Angeles (UCLA) scale | 2 years | Score rating the patient's current activity level * Minimum: 1 (wholly inactive subject) * Maximum: 10 (totally active subject) |
| Pain Visual Analogue Scale | 2 years | Score representing patient's current pain intensity * Minimum: 0 (no pain) * Maximum: 100 (very severe pain) |
| Postel Merle d'Aubigné-Score | 2 years | Score grading the functional value of the hip * Minimum: 0 (worst outcome) * Maximum: 6 ( best outcome) Grading is done in each of the three dimensions: pain, mobility and ability to walk. |
| Hip Disability and Ostheoarthritis Outcome Score | 2 years | Patient reported outcome * Minimum: 0 (best outcome) * Maximum: 96 (worst outcome) |
| Radiographic Evaluation | 2 years | Evaluation of radiographic images regarding implant position, implant fixation, heterotopic ossifications (HO), radiolucencies, osteolysis, atrophy and hypertrophy |
| Number of adverse events | 2 years | Collection of adverse events |
Countries
Germany
Outcome results
None listed