Intraoperative Physician Assessment during total hip arthroplasty correlates with DXA parameters

Abstract

Purpose/Aims

To evaluate Intraoperative Physician Assessment (IPA) during total hip arthroplasty (THA) as a quantitative measure of bone status based on tactile assessment. IPA was compared to DXA-measured bone mineral density (BMD), 3D-Shaper parameters, and radiographic indices to assess its validity for evaluating bone status.

Rationale/Background

The International Society for Clinical Densitometry (ISCD) Official Positions acknowledge the orthopedic surgeons’ ability to assess bone intraoperatively and recommend bone assessment for patients with poor bone quality. Currently, there is no validated method to quantify bone status intraoperatively and correlate it with DXA-parameters. This study sought to fill that void.

Methods

A retrospective analysis identified patients undergoing primary THA who had IPA recorded in the operative report and a DXA within 2 years prior to surgery. Patients were excluded if they had prior surgery on the involved hip. 60 patients (64 hips) operated on by 2 fellowship-trained arthroplasty surgeons were included. Intraoperatively, surgeons subjectively assessed bone quality on a 5-point scale based on tactile feedback. This scale defined 1 as excellent and 5 as poor, as noted in Table 1. IPA score was compared to DXA BMD and T-score, 3D Shaper measurements, WHO classification, FRAX scores, radiographic Dorr classification and Cortical Index. IPA was correlated with bone parameters using the Pearson method for continuous variables and Spearman method for ordinal variables.

Results

Mean (SD) patient age and BMI were 69.1 (8.5) years and 27.7 (5.9) kg/m2 respectively; 54 (84%) were female. Patient demographic data and bone parameters were similar between surgeons. Mean IPA was 2.95 ± 0.98 with no difference between surgeons (p = 0.121). There was a moderate correlation between IPA score and total hip BMD (r = 0.386, p = 0.002) and 3D shaper measurements, including trabecular volumetric BMD (r = -0.326, p = 0.010), cortical surface BMD (r = -0.347, p = 0.006), and cortical thickness (r = -0.381, p = 0.002). There was a strong correlation (all p < 0.001) between IPA score and lowest T-score (r = -0.485), WHO classification (r = 0.528), and FRAX major and hip fracture scores (r = 0.501, 0.622). All patients with below average or poor IPA score had osteopenia or osteoporosis by DXA.

Implications

IPA during THA is a simple, valuable tool for quantifying bone status based on tactile feedback. This information can be used to identify patients with poor bone quality that may benefit from bone health evaluation and treatment.