The Authors retrospectively reviewed a series of 117 patients who had total hip arthroplasty treated for PPFx between January 2013 and March 2018 at our hospital, a tertiary referral center for both trauma and arthroplasty surgeries. All cases were treated by one senior surgeon with more than 10 years’ experience in both RA and ORIF of pelvis and lower limb fractures.
The inclusion criteria for this study were the presence of a periprosthetic fracture around a total or partial hip arthroplasty, the presence of complete clinical and radiological data both in the preoperative and postoperative period. Exclusion criteria were a non-operative treatment due to severe comorbidity and high operative risk, a follow up less than 12 months, pathological fractures for tumors or infection, incomplete clinical or radiological data, like in patients referred from other hospitals. From 117 cases we enrolled 68 patients, accounting for 70 cases, because two patients had bilateral PPFx.
Clinical and demographic data (gender, age, body mass index, side of fracture) were retrospectively gathered from digital clinical records. The highlighted data, the model of prosthetic stem used for revision, the osteosynthesis devices and blood transfusions were collected from (digitally stored) clinical records.
Patients were divided into two groups depending on the surgical treatment, ORIF and RA respectively. Clinical features and overall postoperative complications (infections, hardware failures, dislocations, non-unions, deep venous thrombosis, heart failures and pneumonia) were recorded and related to the fracture classification and the type of surgical management (ORIF or RA). The patients were evaluated for a minimum of four follow-up: 1 month, 3 months, 6 months and 1 year after the surgery. The average time of follow up is 67.2 months.
The periprosthetic femoral fractures were classified and evaluated according to the Unified Classification System (UCS) based on preoperative radiographic, even if the definitive evaluation of stem’s stability was confirmed during the surgical procedures. Fractures are classified as follows: type A, apophyseal or extraarticular fracture (A1: avulsion of great trochanter, A2: avulsion of lesser trochanter); type B, bed of implant (B1: prosthesis stable and good bone; B2: prosthesis loose, good bone; B3: prosthesis loose and poor bone or bone defect); C, clear of or distant to the implant; D, dividing the bone between two implants; E each of two bones supporting one arthroplasty; F, facing and articulating with a hemiarthroplasty [13].
Moreover, we used the CIRS score (Cumulative illness rating scale) to assess patients’ comorbidity level before surgery. This scoring system measures the chronic medical illness taking into consideration the severity of chronic disease across 14 items. Each item has a 0–4 score, where 0 represents “no problem affecting that system” and 4 “extremely severe problem and/or immediate treatment required and /or organ failure and/or severe functional impairment”. The cumulative final score can vary from 0 to 56 [14].
One of the two surgical procedures was performed, based on the type of fracture, the quality of the bone stock, the general conditions of the patient before the fracture (through adequate functional and cognitive assessments) and the associated comorbidities. (Fig. 2). The surgical treatment was mainly decided based on the fracture pattern and stem’s stability, assessed both on preoperative X-Rays and in the operating room, according to the UCS classification. However, the patient’s comorbidities and anesthesiologic consultancy have contributed to clinical and surgical decision. These data have been collected in CIRS score, Oxford and Barthel preoperative score.
No A type fracture have been operated [15]. When the prosthetic implants were considered stable (UCS Classification type B1 or C) [16, 17] ORIF was performed to allow rapid rehabilitation and clinical recovery. In few cases minimally invasive reduction and fixation was performed in patients with very low functional request to reduce surgical morbidity according to preoperative assessment. Prosthetic revision was used in case of loosening of prosthesis stability (type B2) [18] inadequate bone stock (type B3) [19]. We used the postero-lateral approach to the hip with lateral extension to proximal femur, because in our experience it allows a good exposure and direct reduction of the fracture pattern. We performed MIPO approaches only in patients with a C type of fracture, according to classification.
Rehabilitation protocol in both groups focused on rapid recovery of hip mobilization and early muscle strengthening. In RA cases we follow the standard protocol for revision procedures [13], with protection of forced abduction, internal rotation and flexion. Supported weight bearing was allowed for ORIF patients depending on collaboration of the patients, while immediate weight bearing as tolerated was allowed to RA patients.
Authors computed descriptive statistics, looking at medians and interquartile ranges (IQR) for continuous variables and frequencies and proportions for categorical variables. Continuous variables were compared across the two groups using the Student Independent T- test or the Mann-Whitney U test based on their normal or non-normal distribution, respectively. Normality of variables’ distribution was tested by the Kolmogorov-Smirnov test. Categorical variables were tested with the Chi-square and Kruskal-Wallis tests. Differences between pre- and post-treatment variables were assessed using paired T test. Authors used univariate and multivariate ANOVA (MANOVA) with post hoc analyses to compare clinical and surgical variables between groups. Multivariate analysis was performed to explore predictors of Δ Oxford, after adjusting for age, preoperative Barthel and CIRS score. Statistical significance was set at 5%. All tests were two-sided. Analyses were carried out using SPSS v. 24 (IBM SPSS Statistics for Mac, Armonk, NY, IBM Corp).
