Retrospective and Prospective Evaluation of Hip Short Stem Performed by Anterior Approach (AMISP)

Clinical and Radiographic Evaluation of a Short Stem for Primary Hip Replacement Performed by Anterior Approach: A Retrospective and Prospective Study

This study aims to evaluate the clinical, radiographic, and perioperative outcomes of short femoral stems implanted during primary total hip arthroplasty performed through a minimally invasive direct anterior approach (DAA). Short femoral stems have been developed to preserve proximal femoral bone stock, potentially provide a more physiological load transfer, and facilitate implantation through less invasive surgical exposures, particularly in younger and more active patients.

The stem is a cementless hydroxyapatite-coated triple-tapered short stem, has been previously used because its design allows simplified femoral canal preparation and easier implant insertion during minimally invasive anterior approaches, where femoral exposure may be technically demanding. However, previous reports have shown conflicting results regarding implant survivorship and radiographic outcomes, including increased rates of radiolucent lines, pedestal formation, and stem subsidence, particularly among younger and more active patients.

The present study will investigate the technical and clinical implications of using short femoral stems through a minimally invasive anterior approach. Primary outcomes will include perioperative complication rates, wound characteristics, peri-incisional tissue condition, postoperative bleeding, and other surgery-related complications. Secondary outcomes will include postoperative pain, functional recovery, clinical outcome scores, implant survivorship, and serial radiographic findings at short- and mid-term follow-up.

Given the limited evidence currently available regarding the short- and mid-term performance of short femoral stems implanted through the direct anterior approach, this study aims to provide a comprehensive clinical and radiographic evaluation of these implants over time. Adverse events will be continuously monitored through scheduled clinical and radiographic assessments.

Study Overview

• Status: Recruiting
• Conditions: Hip Arthritis
• Intervention / Treatment: Procedure: Total Hip Arthroplasty

• Study Type: Observational
• Enrollment (Estimated): 400

Contacts and Locations

• Study Contact: Name: Stefano Lucchini, MD; Phone Number: 0516366961; Email: stefano.lucchini@ior.it

Study Locations

• Italy
  • Bologna, Italy, 40136
    • Recruiting
    • IRCCS Istituto Ortopedico Rizzoli
    • Contact: Stefano Lucchini, MD; Phone Number: 0516366961; Email: stefano.lucchini@ior.it

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

The study population includes consecutively treated adult patients undergoing primary total hip arthroplasty performed through a direct anterior approach with a cementless femoral component, at the Department of Orthopaedics, Trauma Surgery, and Hip and Knee Arthroplasty and Revision Surgery of the IRCCS Istituto Ortopedico Rizzoli. Patients will be included from 2022 (retrospective cohort) to 2027 (prospective cohort).

Description

Inclusion Criteria:

• Diagnosis of primary hip osteoarthritis or osteonecrosis
• Minimally invasive direct anterior approach
• Cementless femoral component
• Minimum follow-up of 2 years
• Patient willingness to participate in the study with written informed consent
• Age over 18 years
• Male or female patients

Exclusion Criteria:

• Other diagnoses of secondary hip osteoarthritis
• Non-anterior surgical approach
• Cemented or other types of components
• Patient unwillingness to participate in the study
• Inadequate clinical and radiological documentation

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
patients; Patients undergoing total hip arthroplasty for osteoarthritis through a direct anterior approach with a short femoral stem	Procedure: Total Hip Arthroplasty; Total Hip Arthroplasty via Direct Anterior Approach

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Implants survival	Survival of hip implants at the follow up period (survival meaning implants which were not revised for any cause at the follow up perios)	at least 5 years after surgery

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Intra and perioperative complications	The Clavien-Dindo score is a system used to classify and standardize postoperative surgical complications according to their severity and the type of treatment required to manage them. It is widely used in clinical studies and surgical registries because it allows objective comparison of outcomes between different techniques or procedures. It was originally proposed by Pierre-Alain Clavien and later modified by Daniel Dindo.	On the day of the surgery
radiological outcomen 1	osteointegration of the stem according to Le Beguec: Classification of osseointegration according to Emmanuel L. L. Le Béguec: bone ingrowth (stable biological fixation), fibrous fixation (stable but non-osseointegrated interface), and unstable fixation (radiographic and/or clinical signs of loosening).	at least 5 years after surgery
radiological outcome 2	osteointegration of the stem according to Engh: Classification according to Charles A. Engh: stable bone ingrowth fixation (definitive osseointegration), stable fibrous fixation (no progressive loosening despite absence of full bone ingrowth), and unstable fixation (evidence of implant loosening or migration).	at least 5 years after surgery

Collaborators and Investigators

• Sponsor: Istituto Ortopedico Rizzoli

Publications and helpful links

General Publications

• Garavaglia G, Gonzalez A, Barea C, Peter R, Hoffmeyer P, Lubbeke A, Hannouche D. Short stem total hip arthroplasty with the direct anterior approach demonstrates suboptimal fixation. Int Orthop. 2021 Mar;45(3):575-583. doi: 10.1007/s00264-020-04910-5. Epub 2021 Jan 11.
• Giardina F, Castagnini F, Stea S, Bordini B, Montalti M, Toni A. Short Stems Versus Conventional Stems in Cementless Total Hip Arthroplasty: A Long-Term Registry Study. J Arthroplasty. 2018 Jun;33(6):1794-1799. doi: 10.1016/j.arth.2018.01.005. Epub 2018 Jan 11.

Study record dates

Study Major Dates

• Study Start (Actual): September 12, 2025
• Primary Completion (Estimated): September 1, 2027
• Study Completion (Estimated): December 1, 2030

Study Registration Dates

• First Submitted: May 13, 2026
• First Submitted That Met QC Criteria: May 18, 2026
• First Posted (Actual): May 20, 2026

Study Record Updates

• Last Update Posted (Actual): May 20, 2026
• Last Update Submitted That Met QC Criteria: May 18, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Surgical Procedures, Operative; Arthroplasty, Replacement; Arthroplasty; Orthopedic Procedures; Plastic Surgery Procedures; Prosthesis Implantation; Arthroplasty, Replacement, Hip
• Other Study ID Numbers: AMISP 277/2025/Oss/IOR

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No