Eur J Orthop Surg Traumatol (2018) 28:463–469
ORIGINAL ARTICLE • HIP - ARTHROPLASTY
Cementless modular neck stems: are they a safe option in primary
total hip arthroplasty?
José M. Pelayo‑de‑Tomás
· José L. Rodrigo‑Pérez
· Carlos D. Novoa‑Parra
· María Morales‑Suárez‑Varela
José Antonio Blas‑Dobón
Received: 17 August 2017 / Accepted: 14 October 2017 / Published online: 29 October 2017
© Springer-Verlag France SAS 2017
Conclusions The ﬁndings in the present study showed
that the H-MAX-M stem provided satisfactory functional
outcome in most patients with a low rate of complications
attributable to the modular neck design. We consider that
using this novel modular neck-stem coupling design can
be an alternative to the conventional monoblock stems in
patients without overweight.
Keywords Total hip arthroplasty · Modular neck ·
H-MAX M hip system · Functional outcome ·
Pseudotumor · Serum metal ion level
Total hip arthroplasty (THA) is a usual procedure with eﬀec-
tive outcome that relieves pain and restores hip function in
most patients with end-stage hip osteoarthritis. However, the
procedure is not completely failure-free and new designs are
constantly developing . Stems with modular necks were
introduced with the theoretical advantages of optimizing
hip biomechanics and restoring the centre of articular rota-
tion by adjusting the oﬀset, femoral version and lower limb
length for each patient [2, 3]. Nevertheless, these advantages
have not been clinically demonstrated because available evi-
dence is controversial [2, 4, 5]. In addition, modular stems
have had higher revision rates than conventional stems .
On the other hand, several studies have warned of a high rate
of serious failures using modular neck stems, mainly neck
breakage, micromotion and corrosion of the neck . Thus,
the use of modular stems has been widely questioned and
even some model was removed from the global market .
First-generation modular necks were made in titanium,
which oﬀered good micromotion but an inacceptable break-
age rate . Several risk factors for titanium neck breakage
Purpose The objective was to assess aseptic complications
and functional outcome using a primary total hip arthro-
plasty with modular neck.
Methods Prospective cohort of 317 consecutive patients.
The mean age was 61.1 (range, 41–84) years. The H-Max-
M model (Lima, Italy) system was used in all patients. The
functional assessment was made by the Harris Hip Score,
Short Form-36 (SF-36), Western Ontario and McMaster
Universities Osteoarthritis Index and visual analogue scale
for pain. Radiological outcomes were also assessed, and
adverse events and complications were noted.
Results The mean follow-up was 6.1 (range, 2–8) years.
Functional outcome signiﬁcantly improved in most patients.
There were 3 deep infections (0.9%) and 17 aseptic com-
plications (5.3%) including 1 intraoperative acetabular
fracture, 3 later periprosthetic femoral fractures, 1 broken
ceramic insert, 1 acetabular loosening, 3 femoral loosening
and 1 broken titanium modular neck in a obese patient. No
pseudotumors or elevated serum levels of metal ions were
found among the patients with radiolucent lines or aseptic
* Carlos D. Novoa-Parra
Department of Orthopaedic Surgery, Doctor Peset University
Hospital, Av Gaspar Aguilar, 90, 46017 Valencia, Spain
Faculty of Medicine, Miguel Hernandez University, Elche,
Unit of Public Health and Environmental Care, Department
of Preventive Medicine, University of Valencia, Valencia,
CIBER of Epidemiology and Public Health (CIBERESP),