Ipsilateral pubic ramus fracture during total hip arthroplasty is not rare: does it matter?

INTRODUCTION: Periprosthetic fractures in total hip arthroplasty (THA) have been well described and studied. However, there is a lack of reports on ipsilateral pubic ramus fractures during THA due to the rare occurrence of such fractures and ambiguity of symptoms. With the use of postoperative computed tomography (CT) examinations, we have identified that asymptomatic ipsilateral pubic ramus fractures occur frequently during THA. This study aims to evaluate the incidence, location, clinical outcomes, and risk factors of ipsilateral pubic ramus fractures during THA. METHODS: From May 2022 to March 2023, a single surgeon performed 203 THAs in 183 patients at a single institution. All patients underwent postoperative CT scans three days after THA. The patients with ipsilateral pubic ramus fractures were followed up for a minimum of six months. Basic demographics, osteoporosis, general conditions of the operations, and outcomes of THA were investigated in all patients. RESULTS: Twenty-two cases (10.8%) of ipsilateral pubic ramus fractures were identified on postoperative CT scans. All fractures were located near the origin of the superior or inferior pubic ramus. Five fractures were detected on simple postoperative radiographs. The fractures did not cause any further complications at a minimum of six-month postoperative follow-up. Univariate and multivariate analyses did not identify any risk factors associated with these fractures. CONCLUSIONS: Although the incidence of ipsilateral pubic ramus fractures during THA is high, treatment is not required as they do not cause any significant clinical symptoms or affect the prognosis of THA. However, the possibility of occurrence of these fractures must be explained to the patients before surgery.

Novel radiologic indices for stem type decision in total hip arthroplasty in patients with metaphyseo-diaphyseal mismatched Dorr A proximal femur.

BACKGROUND: In metaphyseo-diaphyseal (M-D) mismatched Dorr A femurs, it is difficult to achieve proper fixation with a type 1 stem. Proper interpretation of the geometry of the femur is integral at the preoperative stage in an M-D mismatched femur, but there has been a scarcity of studies on the radiologic indices. Therefore, we analyze the previous radiologic indices and suggest the novel ones for M-D mismatched femurs. METHODS: Our study was a retrospective review of preoperative radiographs of patients who underwent total hip arthroplasty with the smallest type 1 stem or with type 3 C stem at a single institution from July 2014 to March 2022. A Type 3 C stem was used when the smallest type 1 stem failed to achieve metaphyseal fixation. One hundred twenty-six patients were categorized into two main groups. Canal-flare index, canal-calcar ratio, modified morphological cortical index, and two novel indices (lesser trochanter-to-distal ratio-α and -ß [LDR-α and -ß]) were assessed on preoperative pelvic radiographs. RESULTS: Multivariate and ROC analysis demonstrated that high LDR-ß (Exp[B]: 485.51, CI: 36.67-6427.97, p < 0.001) was associated with a more mismatched tendency group and had clinically acceptable discriminatory power (AUC: 0.765, CI: 0.675-0.855, p < 0.001) between the two cohorts. CONCLUSION: Correct assessment of preoperative femoral morphology would be fundamental in the selection of a suitable stem. The ratio based on 3 cm below the lesser trochanter of the femur seemed crucial. We recommend evaluating the newly described radiological index preoperatively in M-D mismatched Dorr A femur for planning precisely and selecting a proper stem.

Minimal pre-operative leg length discrepancy as a risk factor of post-operative leg length discrepancy after total hip arthroplasty: a retrospective study of patients with non-traumatic osteonecrosis of the femoral head.

BACKGROUND: Leg length discrepancy (LLD) is one of the troublesome complications of total hip arthroplasty (THA). Previously, several risk factors have been suggested, but they were subjected to their inherent limitations. By controlling confounding variables, we hypothesized that known risk factors be re-evaluated and novel ones be discovered. This study aimed to analyze the independent risk factors for LLD after primary THA in patients with non-traumatic osteonecrosis of the femoral head (ONFH). METHODS: We retrospectively reviewed patients with non-traumatic ONFH who underwent unilateral THA between 2014 and 2021. All patients were operated by one senior surgeon using a single implant. Demographic data, surgical parameters, and radiological findings (pre-operative LLD, Dorr classification, and femoral neck resection) were analyzed to identify the risk factors of ≥ 5 mm post-operative LLD based on radiological measurement and to calculate odds ratios by logistic regression analysis. Post hoc power analysis demonstrated that the number of analyzed patients was sufficient with 80% power. RESULTS: One hundred and eighty-six patients were analyzed, including 96 females, with a mean age of 58.8 years at the time of initial THA. The average post-operative LLD was 1.2 ± 2.9 mm in the control group and 9.7 ± 3.2 mm in the LLD group, respectively. The LLD group tended to have minimal pre-operative LLD than the control group (-3.2 ± 5.1 mm vs. -7.9 ± 5.8 mm p = 2.38 × 10- 8). No significant difference was found between the groups in age, gender, body mass index, femoral cortical index, and implant size. CONCLUSION: Mild pre-operative LLD is associated with an increased risk of post-operative LLD after primary THA in patients with ONFH. Thus, surgeons should recognize pre-operative LLD to achieve an optimal outcome and must inform patients about the risk of developing LLD.

Ceramic-on-Ceramic or Metal-on-Polyethylene: The Bearing of Choice after Ceramic Component Fracture in Total Hip Arthroplasty along with Concise Follow-Up of the Previous Cohort.

OBJECTIVE: We previously reported the questionable result of reoperation using metal-on-polyethylene (MoP) bearing after the fracture of the ceramic component. After the report, we abandoned the use of MoP; instead, we used ceramic-on-ceramic (CoC) bearing. This report aimed to present the outcome of reoperation to CoC bearing after ceramic component failures along with the longer-term outcome of the previously reported cohort with an MoP bearing. RESULTS: The mean follow-up of the MoP cohort was extended from 4.3 years to 8.8 years. Metallosis had occurred in three of nine patients of the previous cohort, which all required re-reoperations. Two hips from 11 patients with revision to CoC had re-reoperations due to ceramic liner fracture and non-union of the osteotomized fragment, respectively. No metallosis and wear occurred in the cohort revised with CoC articulation. Otherwise, there were no adverse changes in radiographs and no impairment in functions. METHODS: We conducted an extended prospective evaluation of a previous cohort consisting of six head fractures and three liner fractures. In this cohort, the patients underwent a bearing change to metal-on-polyethylene. Additionally, we retrospectively analyzed 11 cases of third-generation ceramic bearing fractures, comprising nine head fractures and two liner fractures. These cases were subsequently treated with a bearing change to fourth-generation CoC. We assessed clinical and radiological outcomes, including complication rates, in both groups. CONCLUSION: We recommend the latest CoC as the bearing of choice in reoperation after the fracture of ceramic components. In the case of an MoP bearing after the ceramic component fracture, the risk of metallosis seemed high in the early postoperative period.

Do the increment of femoral condyle curvature and the change of tibia shape improve clinical outcome in total knee arthroplasty? A propensity score matching analysis.

PURPOSE: Recently, the Persona total knee arthroplasty (TKA) system with more anatomical features and a similarly high flexion to the previous version, LPS-Flex, was introduced and is widely used. This study aimed to compare the early outcomes obtained using Persona versus an LPS-Flex fixed PS implant. METHODS: A total of 784 knees that underwent primary TKAs (162: Persona group and 622: LPS-Flex group) were included. After 1:2 propensity score matching, there were 143 and 286 knees in Persona and LPS-Flex groups, respectively. Range of motion at the 2-year follow-up was the primary variable. Secondary variables were functional score, ability to perform activities requiring deep knee flexion, patient satisfaction, and radiographic measurements, including radiolucent line (RLL). RESULTS: The average postoperative maximal flexion measured by goniometer at 2 years after TKA was 126.1° ± 10.8° (range 95°-140°) for the Persona group and 132.7° ± 11.7° (range 103°-145°) for the LPS-Flex group (P < 0.05). This significant difference was observed from 1 year postoperatively (P < 0.05). The two groups did not show a significant difference in functional score, postoperative ability in high flexion activities, and satisfaction at the 2-year follow-up. The rate of RLL was significantly lower in the Persona group (P < 0.05). CONCLUSION: At the 2-year follow-up, the Persona group had less maximal flexion; however, the difference in flexion did not seem to affect clinical outcomes. According to the radiological results, the Persona system shows less RLL than does the LPS-Flex system. LEVEL OF EVIDENCE: III.

Efficacy of Systemic Steroid Use Given One Day After Total Knee Arthroplasty for Pain and Nausea: A Randomized Controlled Study.

BACKGROUND: Systemic steroid has been used to control pain and nausea in total knee arthroplasty (TKA), but most studies recommend a single dose administration prior to, or during, surgery. This study aimed to determine the efficacy of administration on 1 day postoperatively. METHODS: Patients who were scheduled to undergo TKA were randomly assigned to the following groups: control group, receiving normal saline injection; group 1, receiving 10 mg dexamethasone intravenously (IV) 1 hour before surgery; group 2, receiving 0.1 mg/kg dexamethasone (IV) 24 hours after surgery; or group 3, receiving 0.2 mg/kg dexamethasone (IV) 24 hours after surgery (n = 44-46 per group). Primary outcomes were pain and nausea visual analogue scale (VAS). Secondary outcomes were analgesic administration, rescue antiemetic administration, C-reactive protein, range of motion, and complications. RESULTS: Postoperative pain and nausea remained high for 48 hours post-TKA. Group 1 had lower pain and nausea VAS scores than did the control group (P < .01) for only 24 hours post-TKA. Groups 2 and 3 had lower pain and nausea VAS scores than did the control group and group 1 (P < .01) 48 hours post-TKA. Analgesic and antiemetic administration were significantly lower in groups 2 and 3 than in the control group during 48 hours after TKA. There were no differences in C-reactive protein level and range of motion, and complications were not detected. CONCLUSION: The effect of preoperative and postoperative administration of dexamethasone for controlling pain and nausea was observed only for 24 hours. Considering that severe pain and nausea persisted for more than 48 hours after TKA, additional administration of dexamethasone at 1 day postoperatively is suggested. LEVEL OF EVIDENCE: Level I.