Chapter 18 - Preoperative planning and imaging

Are primary and revision shoulder arthroplasty appropriately reimbursed based on relative value units?

What's New in Shoulder and Elbow Surgery.

Influence of glenoid wear pattern on glenoid component placement accuracy in shoulder arthroplasty.

Severe glenoid bone loss is encountered in a subset of patients with different shoulder pathologies (i.e. osteoarthritis, rotator cuff arthropathy, inflammatory arthritis, failed primary arthroplasty, etc.) managed with shoulder arthroplasty. It creates a challenge for the shoulder reconstructive surgeon due to difficulty in restoring the normal glenoid bony anatomy, achieving stable fixation of the glenoid component, and is associated with increased complications and poor clinical outcomes. Current surgical techniques to reconstruct glenoid bone loss including eccentric reaming and/or bone grafting have limitations in severe cases. Porous metal augments (PMA) have been proposed as a potential solution because of their biomechanical properties similar to cancellous bone, reliable bone ingrowth, and provide stable fixation of orthopaedic implants. Extensive integration of PMA’s for the management of bone loss in hip and knee arthroplasty has yielded positive mid-term results and provides an optimistic future in shoulder arthroplasty. This chapter will outline the background of PMA’s and potential utilization in the management of severe glenoid bone loss in primary and revision shoulder arthroplasty.

Postoperative opioid utilization associated with revision risk following primary shoulder arthroplasty

The effect of proximal humeral bone loss on revision reverse total shoulder arthroplasty

Objectives:The objective of our study is to determine whether the addition of3-dimensional (3D) MRI to standard MRI sequences is comparable to 3D CT scanevaluation of glenoid and humeral bone loss in glenohumeral instability.There is increasing understanding of the importance of the glenoid, as wellas humeral bone loss in outcomes and surgical decision making in patientswith shoulder instability. Although magnetic resonance imaging (MRI) isperformed as standard of care for soft tissue evaluation of shoulderinstability, CT scan remains the gold standard in bony measurements.Standard MRI evaluation has been shown to inaccurately measure bone loss.However, additional CT scans result in increased financial, time, andionizing radiation cost to the patient.Methods:Eighteen patients who presented with glenohumeral instability wereprospectively enrolled and received both MRI and CT within 1 week of eachother. The MRI included an additional sequence (VIBE) which underwentpost-processing for reformations (Figure 1a). The addition of a VIBEprotocol, on average is an addition 4 to 4.5minutes in the scanner. CT dataalso underwent 3D post-processing (Figure 1b) and therefore each patient hadfour imaging modalities (2D CT, 2D MRI, 3D CT reformats, and 3D MRIreformats). Each sequence underwent the following measurements from twoseparate reviewers: glenoid defect, glenoid defect percent, humeral defect,humeral defect percentage (Figure 2a and 2b), and evaluation of glenoidtrack and version. Paired t-tests were used to assess differences betweenimaging modalities and chi squared for glenoid track. Intra-observer andinter-observer reliability were evaluated. Bland-Altman tests were alsoperformed to assess the agreement between CT and MRI. In addition, wedetermined cost of each imaging modality at our single institution.Results:3D MRI measurements for glenoid and humeral bone loss measurements werecomparable to 3D CT (Table 1). There were no significant differences forglenoid defect size and percentage, or humeral defect size and percentage(P>0.05) (Table 2). Bland-Altman analysis demonstrated strong agreementwith small measurement errors for 3D CT and 3D MRI percentage glenoid boneloss. There was also no difference in evaluation for determining on vs offtrack between any of the imaging modalities. Inter- and intra-raterreliability was good to excellent for all CT and MRI measurements (r >=0.7).Conclusions:3D MRI measurements for bone loss in glenohumeral instability throughutilization of VIBE sequence were equivalent to 3D CT. At our institution,the costs of MRI with 3D reconstruction was 1.67x cheaper than MRI and CTwith 3D reconstructions. 3D MRI may be a useful adjuvant to standard MRIsequences to allow concurrent soft tissue and accurate assessment of glenoidand humeral bone loss in glenohumeral instability.Figure 1a.(3D MRI glenoid reformation) and lb (3D CT glenoid reformation):Glenoid measurement for 3D reconstruction of MRI and CT usingsagittal en face of the glenoid. A circle was placed over theinferior portion of the glenoid using margins as a guide for thecircle. The glenoid height line (blue) runs from the supraglenoidtubercle to the medial aspect of the inferior base. Glenoid boneloss size (orange) and circle diameter (green) was quantified withglenoid height line marking the center of the circle. Percentglenoid bone loss was determined as [(glenoid bone loss size/circlediameter)* 100]. Glenoid track was determined through equation[(0.83 * circle diameter) - glenoid bone loss size]Figure 2a.(2D CT) and 2b (3D CT): 2a: Measurement of Hill Sachs maximal defecton axial 2D CT recorded in mm. 2b: Measurement of humeral defectpercentage from the 3D reformats using sagittal projection with bestfit circle. A line (blue) was placed to determine maximal humeralhead height (A) then perpendicular line (green) to measure residualhumeral head (B) and therefore bone defect (A-B)(orange). Percentbone loss was determined through [(A-B)/A)*100]Table 1:Mean 2D and 3D CT and MRI measurementsTable 2:Paired t-test Glenoid and Humeral Bone Loss Measurements.

Joint replacement surgery as a treatment for glenohumeral arthritis with glenoid bone loss is challenging. The aim of this study is to offer an anatomical orientation for glenoid reconstruction. In this study, we measured size, inclination and version of the glenoid surface, as well as the distance between the articular line of the glenoid, base of the coracoid process, and acromion using computer tomographic (CT) imaging of 131 study participants aged 19-88years in the period of 2010-2013. We measured a mean distance of 6.5 ± 0.2mm from the glenoid articular line to the base of the coracoid process in the transverse CT plane. Body height has shown no significant impact on the glenoid morphology. We observed significant differences between males and females: The glenoid appeared to be located 5.2 ± 0.9mm higher and the humeral head was 4.5 ± 0.7mm larger in male subjects compared with females (r = .699; p < .01). In our study, the base of the coracoid offers an anatomical reference during reconstruction of the glenoid in primary and revision shoulder arthroplasty. As only 2D-CT imaging allows for accurate assessment of glenoid bone defects, we consider conventional X-ray imaging insufficient for proper preoperative planning before shoulder arthroplasty. III.

Chapter 7 - Preoperative planning and imaging

Does long-term follow-up and monitoring of primary shoulder arthroplasty identify failing implants requiring revision?

Crucial to the success of any total or reverse shoulder arthroplasty (RSA) is the stability of the glenoid component fixation. Instability can lead to early implant failure and unsatisfactory results. Patients often present with varying forms of glenoid bone loss (GBL) in both the primary and revision settings, which can be a challenge for the treating surgeon. Severe cases of GBL can increase the risk of potential complications and diminish implant longevity. The use of the reverse total shoulder replacement has been particularly helpful when addressing significant glenoid bony defects. Various approaches have been proposed to deal with GBL, all of which require an individualized assessment of the specifics of the defect in order to provide maximal fixation and thereby optimize the longevity of the shoulder arthroplasty. This article aims to review the recent literature on GBL in shoulder arthroplasty to provide guidance when considering treatment based on the best available evidence. PubMed, MEDLINE, EMBASE, AccessMedicine, ClinicalKey, DynaMed, and Micromedex were queried for publications utilizing the following keywords: "glenoid bone loss" AND "glenoid bone deficiency" AND "shoulder arthroplasty" AND "classification". The search was restricted to research published between 2004 and 2023. There were no restrictions on study type or language. GBL should be critically evaluated prior to undertaking total shoulder arthroplasty (TSA). The treating surgeon should be aware of various methods of addressing bone defects. The use of TSA is increasing to address various shoulder pathologies. Addressing glenoid bone defects is of critical importance to maximize the longevity and outcome of TSA.

Medical comorbidities and perioperative allogeneic red blood cell transfusion are risk factors for surgical site infection after shoulder arthroplasty

Evaluating the utility of perioperative laboratory tests in primary shoulder arthroplasty

Objectives: The concept of the “inverted pear” glenoid was introduced by Lo and Burkhart as an indicator of significant attritional glenoid bone loss that predisposes patients to recurrent instability and higher failure of arthroscopic Bankart repair. Coracoid transfer (Latarjet) is often performed in this setting, and evaluation of coracoid dimensions may improve patient-specific preoperative planning. The purpose of this study was to utilize computed tomography (CT) to determine a reproducible method for coracoid measurement and develop a preoperative planning algorithm for glenoid pear restoration using the traditional Latarjet technique or congruent arc modification (CAM). We hypothesized that classic Latarjet technique would sufficiently restore at least 100% of the glenoid diameter, up to 30% of anterior bone loss. We also hypothesized that most female patients would have a coracoid thickness &lt;10 mm, which may preclude the use of the CAM due to a risk of graft fracture with screw insertion. Methods: Multiplanar reconstructed (MPR) shoulder CT scans were reviewed for patients aged 18-45. This age group was selected to capture an adult population that typically undergoes anterior shoulder stabilization surgery. Patients were excluded if CT scan demonstrated glenoid or humeral osteophyte formation, glenoid dysplasia, coracoid fracture, or tumor involving the glenoid or coracoid. All CT scans were obtained with the arm at the patient’s side, palm facing up, and the shoulder in external rotation. CT scans were performed by acquiring thin-slice data from the volumetric CT in the axial plane with a Discovery CT750 HD scanner (GE Healthcare) and the following scan parameters: 0.625-mm slice thickness, 0.313-mm slice spacing, reconstruction matrix of 512 × 512 pixels, reconstruction field of view of 40 to 45 cm, and pitch factor of 0.516. All measurements were performed using a PACS system (Sectra Workstation, Sectra AB, Linkoping, Sweden) by a board-certified musculoskeletal radiologist and two orthopaedic surgeons. The coracoid base was aligned in the coronal plane, and the long axis of the coracoid was aligned in the axial and sagittal planes (Figure 1). The coracoid length (proximal to distal) was measured on the modified axial view as the distance from the base to the tip along the long axis. The width (medial to lateral) and thickness (anterior to posterior) were measured on the modified coronal view. Coracoid dimensions were compared by sex and correlated with patient height and body mass index (BMI). Best-fit circle technique was used to quantify glenoid diameter and bone loss required for complete graft apposition of a 20- or 25-mm long coracoid graft to the glenoid neck. The proportion of glenoid diameter able to be restored using the classic Latarjet technique and the CAM was calculated and compared. The proportion of patients in which at least 20%, 30%, 35% or 40% of glenoid diameter could be restored using the classic Latarjet technique and the CAM was determined and compared. Based on these findings, a treatment algorithm was proposed considering glenoid bone loss, glenoid diameter and coracoid dimensions. Results: A total of 120 CT scans were reviewed, and three were excluded (two with osteophytes and one with severe glenoid dysplasia). Measurements were performed and dimensions recorded on 117 CT scans (69.2% males). Coracoid dimensions varied considerably among patients (length: 17.5-31.8mm, width: 9.1-20.5mm, thickness: 6.1-15.7mm, Table 1). There was a strong positive correlation between patient height and coracoid length (r=0.629, p=0.000) and a moderate positive correlation between patient height and coracoid thickness (r=0.408, p=0.000). Mean coracoid and glenoid dimensions were larger in males than females (all p&lt;0.0001). When comparing males and females, a higher proportion of males had a coracoid thickness &gt;10mm (84.0% vs 27.8%, p&lt;0.00001). While there was no difference in the proportion of males compared to females with coracoid length &gt;20 mm (96.3% vs 94.4%, p=0.65), a higher proportion of males had coracoid length &gt;25mm (48.2% vs 13.9%, p=0.0009). Compared to the classic Latarjet technique, the CAM was able to restore more native glenoid diameter in both males and females (Males: 54.1±6.6% vs 39.1±4.9%, p&lt;0.0001; Females: 54.7±7.4% vs 36.2±4.3%, p&lt;0.0001, Table 2). When comparing techniques, there was no difference in the proportion of patients in which at least 30% glenoid bone loss could be fully restored (Males: 98.8% vs 97.5%, p=1.0; Females: 100% vs 91.7%, p=0.24). However, the CAM was able to restore at least 35% and at least 40% glenoid bone loss in a higher proportion of males (98.8% vs 79% and 98.8% vs 40.7%, respectively, both p&lt;0.0001) and females (100% vs 61.1% and 100% vs 16.7%, respectively, both p=0.00001). The amount of glenoid bone loss required for complete coracoid graft apposition of a 20mm or a 25mm graft was significantly different when comparing males and females, with less bone loss required for males (14.4±2.8% vs 20.7±5.5% and 26.8±7.5% vs 41.4±9.4%, respectively, both p&lt;0.0001). Intra- and inter-rater reliability was excellent for all coracoid dimensions (ICC≥0.95±0.050 for each). Conclusions: We describe a reliable method of measuring coracoid dimensions for preoperative planning of glenoid pear restoration. The traditional Latarjet technique reliably restores the glenoid AP diameter with bone loss of up to 30%. The majority of females have coracoid thickness &lt;10mm which may increase the risk of graft fracture when using CAM. The decision to utilize the classic Latarjet technique or CAM considers each individual’s glenoid and coracoid dimensions with a goal of achieving at least 100% restoration of native glenoid diameter (Figure 2). Alternative techniques may be considered if native glenoid pear restoration cannot be achieved with the Latarjet. [Table: see text][Table: see text]

Tranexamic acid reduces blood loss after primary shoulder arthroplasty: a double-blind, placebo-controlled, prospective, randomized controlled trial