Assessment of Implant Fixation and SF-36 for Short Hip-Stems - A Prospective Clinical Study

Completed

• Conditions: Primary and Secondary Coxarthrosis; Dysplasia Coxarthrosis; Post-traumatic Necrosis of the Femoral Head
• Interventions: Device: Total Hip Arthroplasty

• Registration Number: NCT04172129
• Lead Sponsor: Smith & Nephew Orthopaedics AG

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).

Detailed Description

Not available

Study Timeline

• Study Start: 2011-04-26
• Primary Completion: 2017-01-04
• Study Completion: 2017-02-15
• Status Verified: 2019-11
• Study First Submitted: 2019-11-19
• Study First Submitted QC: 2019-11-19
• Study First Posted: 2019-11-21
• Last Update Submitted: 2019-11-25
• Last Update Posted: 2019-11-27

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 60

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.

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Arm && Interventions

Group	Intervention	Description
NANOS	Total Hip Arthroplasty	NANOS™ Neck Preserving Hip Stem

Primary Outcome Measures

Name	Time	Method
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 Outcome Measures

Name	Time	Method
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)
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.
Radiographic Evaluation	2 years	Evaluation of radiographic images regarding implant position, implant fixation, heterotopic ossifications (HO), radiolucencies, osteolysis, atrophy and hypertrophy
Harris Hip Score	2 years	Investigator assessed outcome score Minimum: 0 (worst outcome) Maximum: 100 (best outcome)
Hip Disability and Ostheoarthritis Outcome Score	2 years	Patient reported outcome; * Minimum: 0 (best outcome); * Maximum: 96 (worst outcome)
Pain Visual Analogue Scale	2 years	Score representing patient's current pain intensity; * Minimum: 0 (no pain); * Maximum: 100 (very severe pain)
Number of adverse events	2 years	Collection of adverse events

Trial Locations

Locations (1)

Orthopädische Klinik der Medizinischen Hochschule Hannover; 🇩🇪 Hannover, Germany