This study aimed to verify the hypothesis that an antibiotic loaded hydrogel, defensive antimicrobial coating (DAC), reduces overall complication and infection rates when used for high-risk primary and revision total hip arthroplasty (THA).

This was a retrospective study matched cohort study of 238 patients, treated with cementless implants with and without DAC. A sub-group analysis of patients undergoing 2nd stage revision THA for prosthetic joint infection (PJI) was also conducted. Re-infection rates within 2 years, complications necessitating surgical intervention and radiographic analysis for aseptic loosening was assessed.

The mean age was 68.3±11.5 years, with 39 (32.8%) Macpherson class A, 64 (53.8%) class B and 16 (13.4%) class C patients. 4 (3.4%) patients in the DAC group developed complications including 1 PJI and 1 delayed wound healing, while 13 (10.9%) patients in the control group developed complications including 5 PJIs and 3 delayed wound healing (p=0.032). PJI rates (p=0.136) and delayed wound healing rates (p=0.337) were not statistically significant. For 2nd stage revision THA for PJI there were 86 patients in the DAC group and 45 in the control group. 1 (1.2%) patient in the DAC group developed complications with no recurrences of infection or delayed wound healing, while 10 (22.2%) patients in the control group developed complications including 4 recurrent PJI and 1 delayed wound healing (p=0.003). Recurrent PJI rates were statistically significant (p=0.005) while delayed wound healing rates were not (p=0.165). Patients treated with DAC also had lower rates of aseptic loosening (0% vs 6.7%; p=0.015).

Antibiotic impregnated hydrogel coatings on cementless implants showed decreased complication rates after complex primary or revision THA. In 2nd stage revision THA for PJI, it was associated with reduced risk of re-infection and aseptic loosening.

Stem loosening can be associated with a wide spectrum of bone loss and deformity that represent key factors for choosing the most appropriate revision implant. The aim of this study was to evaluate the clinical outcomes and the survivorship of a consecutive series of THA revisions using a taper rectangular cementless stem for primary implants (Alloclassic® Zweymuller®, Zimmer Warsaw US) at medium-term follow-up.

We retrospectively evaluated 113 patients (115 revisions) who underwent femoral revision with Zweymuller stem with a preoperative Paprosky I (86) or II (29) defects from January 2011 to December 2020. The mean follow up was 6 years (2–10). The median age at time of surgery was 71(41–93) with 60 males and 53 females. Osteolysis/radiolucency were observed in the following Gruen zones: I (91), II (3), III (2), VII (15), V (3), VI (1). Clinical assessment was performed by means of Harris Hip Score (HHS) and Visual Analogic Scale (VAS), whereas for the radiological analysis we used conventional x-rays of the hips. The statistical analysis was performed using Graphpad Prism v5.0 and data distribution was assessed by Shapiro-Wilk test, and Wilcoxon matched paired test was used to test the differences between preoperative and postoperative score.

9 patients were lost to fu (deceased or not available), 104 (106 hips) were evaluated. The mean HHS and VAS significantly improved at final follow-up, going from 33,84 and 5,78 preoperatively to 66,42 and 2,05 postoperatively, respectively. 28 patients (25%) showed unprogressive radiolucent lines in Gruen zones 1 and 7 with no other radiological nor clinical signs of loosening. One patient suffered from recurrence of the infection. The survivorship with stem revision as endpoint was 100%.

Alloclassic Zweymüller primary stem showed good medium-term results and survival rate in revision THA for aseptic loosening and second stages of two stage revisions.

Instability continues to be a troublesome complication after THA and has been reported to be the main indication for revision in the United States, accounting for 22.5% of revisions. Risk factors associated with dislocation include: age of 75 years or older, body mass index (BMI) of 30 kg/m2 or greater, alcohol abuse, and neuro-degenerative diseases such as multiple sclerosis or Parkinson's disease. Dual-mobility articulations have become an increasingly popular option for these “at risk” primary THAs. Few studies have assessed their use in this complex patient population. The purpose of this study was to assess dislocation rate, radiographic outcomes and complications of the dual-mobility articulation in the setting of primary THA for patients at high risk for dislocation at a minimum follow up of 2 years.

We retrospectively reviewed 151 dual mobility acetabular components, that had been performed using a single design (ADM Stryker, Mahwah, NJ) between 2010 and 2014 at a single institution by a single surgeon. The mean age at time of index surgery was 82 years (range, 73–95), 114 patients were female, and mean BMI was 26.2 kg/m2 (range, 16.1–60.9). Dislocation rate and complications associated with dual mobility cups were reviewed, along with the radiographic outcomes after an average follow-up period of 3.6 years (range, 1.9–6.1 years).

The indication for hip replacement was osteoarthritis in all cases. We had one traumatic dislocation which required component revision after intraprosthetic dislocation following an attempt of closed reduction. There were no further dislocations in this cohort. No progressive radiolucencies or component positional changes were seen on radiographic assessment.

At short-term follow-up dual mobility provides a stable reconstruction in patients at high risk of dislocation with excellent radiographic results. Longer follow-up is needed to confirm the durability of these reconstructions.

Proximal femoral replacements are commonly used in oncologic limb salvage procedures. Recently, these megaprostheses have been utilized in complex revision arthroplasties where proximal femoral bone is compromised. The purpose of this study is to evaluate the clinical and radiographic survivorship of proximal femoral replacements as a salvage treatment for bone loss after hip arthroplasty. We retrospectively reviewed the clinical and radiographic outcomes of 31 proximal femoral replacements of a single design between 2004 and 2013 at a single institution. The mean age at time of index surgery was 62 years, 58% were female, and mean BMI was 28.1 Kg/m². The indications and complications associated with megaprosthesis implantation were collected. Average follow-up was 60 months (range 24–120 months). Kaplan-Meier survivorship assessed clinical and radiographic survivorship. Indication for revision, use of a constrained liner and construct length were assessed as risk factors for construct failure.

The indications for proximal femoral replacement were periprosthetic infection (n=12, 38.7%), aseptic loosening (n=10, 32.3%), periprosthetic fracture (n=6, 19.3%), and non-union (n=3, 9.7%). A constrained liner was used in 22 hips (71%). The average length of bone resection was 148 cm (range 81–240 cm). There were nine revisions (29.2%): 3 for infection (9.7%) 2 for dislocation (6.5%), 2 for aseptic loosening (6.5%), and 2 for periprosthetic fracture (6.5%). Two of the 3 infections were in patients treated for infection. Overall survivorship was at 70.8%. There was no relation between the length of the bone resection, indication for revision and failure rate.

Proximal femoral replacement in non-oncologic revision hip arthroplasty demonstrated a high failure rate at 2–10 year follow-up. Despite the high failure rate, the benefits of this salvage construct are that they allow full weight-bearing and allow rapid mobilization with minimal morbidity.

Background

Tapered cementless femoral components have been used in total hip arthroplasty (THA) constructs for more than 20 years. The Synergy femoral component was introduced in 1996 as a second generation titanium proximally porous-coated tapered stem with dual offsets to better restore femoral offset at THA (Figure 1). The purpose of this study was to evaluate the outcome of the authors' experience using the Synergy stem at minimum 15 years of follow-up.