Did the dislocation risk after primary total hip arthroplasty decrease over time? A meta-analysis across six decades.

BACKGROUND: While continuous optimization is attempted to decrease the incidence of dislocation after total hip arthroplasty (THA), dislocation remains a major complication. This meta-analysis aims to analyze the evolution of the dislocation risk after primary THA over the decades and to evaluate its potential publication bias. PATIENTS AND METHODS: A systematic search was performed according to the PRISMA guidelines for this meta-analysis in the literature published between 1962 and 2020. MEDLINE, Cochrane and Embase databases were searched for studies reporting the dislocation risk and length of follow-up. Studies that reported on revision rates only and did not mention separate dislocations were excluded. All study designs were eligible. Study quality was assessed by existing quality assessment tools adjusted for arthroplasty research. Overall risk and yearly dislocation rates were calculated and related to historical time frame, study design, sample size and length of follow-up. RESULTS: In total, 174 studies were included with an overall moderate quality. In total there were 85.209 dislocations reported in 5.030.293 THAs, showing an overall dislocation risk of 1.7%, with a median follow-up of 24 months. The overall dislocation risk classified per decade decreased from 3.7% in 1960-1970 to 0.7% in 2010-2020. The yearly dislocation rate decreased from 1.8 to 0.7% within these same decades. There was no significant correlation between the reported dislocation risk and the duration of follow-up (p = 0.903) or sample size (p = 0.755). The reported dislocation risk was higher in articles with registry data compared to other study designs (p = 0.021). CONCLUSION: The dislocation risk in THA has been decreasing over the past decades to 0.7%. Non-selective registry studies reported a higher dislocation risk compared to studies with selective cohorts and RCTs. This indicates that the actual dislocation risk is higher than often reported and 'real-world data' are reflected better in large-scale cohorts and registries.

Heterotopic ossification in primary total hip arthroplasty using the posterolateral compared to the direct lateral approach.

PURPOSE: Total hip arthroplasty (THA) is a successful procedure. However, in time, heterotopic ossification (HO) can form due to, amongst others, soft tissue damage. This can lead to pain and impairment. This study compares the formations of HO between patients who underwent either THA with the posterolateral approach (PA) or with the direct lateral approach (DLA). Our hypothesis is that patients who underwent THA with a PA form less HO compared to THA patients who underwent DLA. METHODS: In this prospective cohort study, 296 consecutive patients were included who underwent THA. A total of 127 patients underwent THA with the PA and 169 with the DLA. This was dependent on the surgeon's preference and experience. More than 95% of patients had primary osteoarthritis as the primary diagnosis. Clinical outcomes were scored using the Numeric Rating Scale (NRS) and Harris Hip Score (HHS), radiological HO were scored using the Brooker classification. Follow-up was performed at 1 and 6 years postoperatively. RESULTS: Two hundred and fifty-eight patients (87%) completed the 6-year follow-up. HO formation occurred more in patients who underwent DLA, compared to PA (43(30%) vs. 21(18%), p = 0.024) after 6 years. However, the presence of severe HO (Brooker 3-4) was equal between the DLA and PA (7 vs. 5, p = 0.551). After 6 years the HHS and NRS for patient satisfaction were statistically significant higher after the PA (95.2 and 8.9, respectively) compared to the DLA (91.6 and 8.5, respectively) (p < 0.001 and p = 0.003, respectively). The NRS for load pain was statistically significant lower in the PA group (0.5) compared to the DLA group (1.2) (p = 0.004). The NRS for rest pain was equal: 0.3 in the PA group and 0.5 in the DLA group. CONCLUSION: THA with the PA causes less HO formation than the DLA. TRIAL REGISTRATION: Registrated as HipVit trial, NL 32832.100.10, R-10.17D/HIPVIT 1. Central Commission Human-Related research (CCMO) Registry.

Bilateral Slipped Capital Femoral Epiphysis in a Young Girl Treated With Chemotherapy: A Case Report.

CASE: A 1-year-old girl was treated with chemotherapy and hematopoietic stem cell transplantation because of CD40 ligand deficiency. Four years later, she presented with pain in her right leg, diagnosed as atypical acute slipped capital femoral epiphysis, without a clear cause, besides chemotherapy possibly. She was treated with fixation of the epiphysis with a cannulated screw. Two years later, the same diagnosis was made for the left hip and the same surgery was applied. After the 2-year follow-up, clinical outcomes were good. CONCLUSION: Chemotherapy may be a risk factor for atypical slipped capital femoral epiphysis, even without the combination with radiotherapy.

Current Evidence for Spinopelvic Characteristics Influencing Total Hip Arthroplasty Dislocation Risk.

BACKGROUND: Decreased pelvic mobility and pelvic retroversion may result from spinal degeneration and lead to changes in the orientation of the acetabular implant after total hip arthroplasty (THA). While multiple patient and surgery-related factors contribute to THA dislocations, there is increasing evidence that sagittal spinopelvic dynamics are relevant for THA stability. The aim of this systematic review was to assess the relationship between previously described sagittal spinopelvic characteristics and implant dislocations after primary THA. METHODS: A comprehensive literature search in the PubMed and Embase databases was conducted for studies reporting on spinopelvic morphology, alignment, pathology, or surgery and THA dislocations. Risk of bias was assessed using the MINORS criteria. Because of high heterogeneity in study methodology, a synthesis of best evidence was performed. Odds ratios (ORs), relative risks (RRs), and effect sizes (g) were calculated. RESULTS: Fifteen studies (1,007,900 THAs) with quality scores of 15 to 23 out of 24 were included. Nine different spinopelvic alignment parameters (8 studies, g = 0.14 to 2.02), spinal pathology (2 studies, OR = 1.9 to 29.2), and previous spinal fusion surgery (8 studies, OR = 1.59 to 23.7, RR = 3.0) were found to be related to THA dislocation. Conflicting results were found for another sagittal pelvic morphology parameter, pelvic incidence. CONCLUSIONS: Several sagittal spinopelvic patient characteristics were found to be related to THA dislocation, and the associated risks were greater than for other patient and surgery-related factors. Future research is needed to determine which of those characteristics and parameters should be taken into account in patients undergoing primary THA. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Uncemented total hip arthroplasty; increased risk of early periprosthetic fracture requiring revision surgery in elderly females.

PURPOSE: The preferred method of stem fixation in total hip arthroplasty (THA) remains debatable. Uncemented THA favors a lower rate of aseptic loosening but has an increased risk of early periprosthetic fractures (EPF). We hypothesize that routine placement of uncemented THA by experienced surgeons diminishes this EPF-risk. The purpose of this study is to investigate the effect of age, gender, ASA classification and BMI of THA performed by experienced surgeons on the risk of EPF. METHODS: A retrospective cohort study including all primary THAs and revision surgeries performed between 2012 and 2018. Possible predictive factors included are age, gender, BMI, ASA classification, presence of osteoporosis, Dorr classification, revision surgery type and clinical outcome. A number needed to treat (NNT) analysis was conducted assuming that cementing THA prevents EPF. RESULTS: 2635 primary THAs were performed. Indications for 70 revisions included 18 EPF in uncemented THA female patients. Periprosthetic fractures without a relevant trauma occurred within six weeks in 16 patients. There was a statistically significant correlation between EPF-risk and age (P = 0.032), female gender (P = 0.001) and ASA classification (P = 0.015). For age ≥75, there was an increase in EPF (P = 0.047). With the assumption that cementing would prevent EPF, the NNT is 48. No statistically significant correlation was found between EPF and BMI, osteoporosis or Dorr classification. CONCLUSION: Female patients aged ≥75 have an increased EPF-risk after uncemented THA and would therefore benefit from treatment with a cemented stem. An ASA score of III-IV is an independent risk factor for EPF after uncemented THA.

Shoulder surgery in beach chair position causing perioperative stroke: Four cases and a review of the literature.

Perioperative stroke is a rare, but serious complication in shoulder-arthroscopy or arthroplasty. Recent literature suggests the beach chair position, widely used during shoulder surgery, might induce severe perioperative hypotension, and with this cerebral desaturation and ultimately perioperative stroke. In this article we report four cases of perioperative stroke in shoulder surgery. In all cases, patients underwent brief periods of hypotension, which might have caused perioperative stroke. Based on an analysis in our hospital, we think the prevalence of perioperative stroke during shoulder surgery is higher than reported. Surgeons should be aware of this risk when using the beach chair position.

[AbstractA woman with knee pain after a fall in childhood]. / Een vrouw met kniepijn na een val op kinderleeftijd.

A 32-year-old woman presented with pain in her left knee ever since she had fallen down the stairs as a child and had landed on this knee. On the X-ray we saw two large patella fragments. We made the diagnosis of dislocated and subluxated fracture of the patella without consolidation. The previously missed fracture was treated conservatively.