Clinical trial NCT03147131: Periprosthetic Bone Mineral Density Changes After Implantation Of A Short Hip Stem Compared To A Straight Stem
Official title: Periprosthetic Bone Mineral Density Changes After Implantation Of A Short Hip Stem Compared To A Straight Stem: Five-Year Results Of A Prospective, Randomized DEXA-Analysis
Study type: INTERVENTIONAL
Overall status: UNKNOWN
Phase: NA
Conditions: Osteoarthritis, Hip
Keywords: Total Hip Arthroplasty
Short Stem
DEXA
Lead sponsor: University Hospital Ulm
Sponsor class: OTHER
First posted: 2017-05-10
Enrollment: 126
Sex: ALL
Minimum age (years): 18
Maximum age (years): 75
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: TREATMENT

Brief summary: The aim of this study is to evaluate periprosthetic bone mineral density (BMD) changes in the proximal femur after implantation of the Fitmore compared to the CLS stem.

Detailed description: After power analysis, 140 consecutive patients were prospectively included in the randomisation protocol receiving either a Fitmore short or a CLS straight stem. The short stem was assigned in 57 (37% females) cases and the straight stem in 83 (38% females) hips. Periprosthetic bone mineral density was measured before surgery, 7 days, 3, 12 and 60 months postoperatively, using dual energy x-ray absorptiometry (DEXA). The results of the first postoperative measurement served as the baseline value. Because of the different length of the two prostheses we used adapted Gruen zones to divide the periprosthetic bone in seven regions of interest (ROI) with equal length in the proximal zones 1,2,6 and 7, only the regions 3 and 5 featured different sizes. Clinical results were recorded using the WOMAC and the Harris hip score (HHS).

Eligibility criteria: Inclusion Criteria:

* Primary or secondary osteoarthritis of the hip
* written informed consent
* indication for cementless total hip arthroplasty

Exclusion Criteria:

* previous surgery in the same hip
* femoral fracture
* metabolic bone disease
* drugs affecting bone quality
* contralateral THA within the study period
* infectious disease or bony tumor

Primary outcomes:
measure: Stem specific stress shielding of a short compared to a straight hip stem
timeFrame: Five years postoperatively
Secondary outcomes:
measure: Clinical Outcome after short compared to straight stem THA
timeFrame: Five years postoperatively
Other outcomes:
Locations:
Study officials:
affiliation: University Hospital Ulm - Department of Orthopedic Surgery
name: Ralf Bieger, PD Dr.
role: PRINCIPAL_INVESTIGATOR
References:
citation: Freitag T, Hein MA, Wernerus D, Reichel H, Bieger R. Bone remodelling after femoral short stem implantation in total hip arthroplasty: 1-year results from a randomized DEXA study. Arch Orthop Trauma Surg. 2016 Jan;136(1):125-30. doi: 10.1007/s00402-015-2370-z. Epub 2015 Nov 27.
citation: Meyer JS, Freitag T, Reichel H, Bieger R. Mid-term gender-specific differences in periprosthetic bone remodelling after implantation of a curved bone-preserving hip stem. Orthop Traumatol Surg Res. 2020 Dec;106(8):1495-1500. doi: 10.1016/j.otsr.2020.04.023. Epub 2020 Oct 31.