Aaron J. Bois

Complications of Shoulder Arthroplasty

Early and mid-range followup studies of shoulder arthroplasty have been encouraging, showing good and excellent results in > 90% of shoulders. Despite this success, complications in shoulder replacement surgery are inevitable, with an incidence of approximately 14%. Numerous complications have been identified and include the following factors in order of decreasing frequency: instability, rotator cuff tear, ectopic ossification, glenoid component loosening, intraoperative fracture, nerve injury, infection, and humeral component loosening. Successful treatment of these difficulties requires careful identification and subsequent analysis of all factors contributing to the complication, knowing that the etiology is often multifactorial. Failed shoulder arthroplasty can be successfully managed with revision surgery, but the technically challenging surgery and the overall results are inferior compared with other diagnostic categories.

USING THE MODIFIED DELPHI METHOD TO ESTABLISH CLINICAL CONSENSUS FOR THE DIAGNOSIS AND TREATMENT OF PATIENTS WITH ROTATOR CUFF PATHOLOGY

BackgroundPatients presenting to the healthcare system with rotator cuff pathology do not always receive high quality care. High quality care occurs when a patient receives care that is accessible, appropriate, acceptable, effective, efficient, and safe. The aim of this study was twofold: 1) to develop a clinical pathway algorithm that sets forth a stepwise process for making decisions about the diagnosis and treatment of rotator cuff pathology presenting to primary, secondary, and tertiary healthcare settings; and 2) to establish clinical practice guidelines for the diagnosis and treatment of rotator cuff pathology to inform decision-making processes within the algorithm.MethodsA three-step modified Delphi method was used to establish consensus. Fourteen experts representing athletic therapy, physiotherapy, sport medicine, and orthopaedic surgery were invited to participate as the expert panel. In round 1, 123 best practice statements were distributed to the panel. Panel members were asked to mark “agree” or “disagree” beside each statement, and provide comments. The same voting method was again used for round 2. Round 3 consisted of a final face-to-face meeting.ResultsIn round 1, statements were grouped and reduced to 44 statements that met consensus. In round 2, five statements reached consensus. In round 3, ten statements reached consensus. Consensus was reached for 59 statements representing five domains: screening, diagnosis, physical examination, investigations, and treatment. The final face-to-face meeting was also used to develop clinical pathway algorithms (i.e., clinical care pathways) for three types of rotator cuff pathology: acute, chronic, and acute-on-chronic.ConclusionThis consensus guideline will help to standardize care, provide guidance on the diagnosis and treatment of rotator cuff pathology, and assist in clinical decision-making for all healthcare professionals.

Humeral Head Arthroplasty and Meniscal Allograft Resurfacing of the Glenoid: A Concise Follow-up of a Previous Report and Survivorship Analysis.

The two to five-year results of humeral head arthroplasty and lateral meniscal allograft resurfacing of the glenoid in patients fifty-five years of age or younger were previously reported by the senior author (M.A.W.). The purpose of the present study was to report the survival rate, clinical findings, and radiographic results of the original thirty shoulders (thirty patients) followed for a mean duration of 8.3 years (range, five to twelve years). The scores on the visual analog scale for pain, American Shoulder and Elbow Surgeons scoring system, and Simple Shoulder Test were significantly improved at the latest follow-up evaluation compared with the preoperative findings (p < 0.001). Radiographic indices of posterior subluxation did not significantly increase from the immediate postoperative imaging to the latest radiographs, while the glenohumeral joint space demonstrated a gradual decrease. Nine (30%) of thirty shoulders were known to have undergone a reoperation. The present study demonstrated that biological glenoid resurfacing combined with hemiarthroplasty can provide significant improvement in shoulder function and pain relief in young patients with glenohumeral arthritis; however, mid-term follow-up at a mean of over eight years demonstrated a high reoperation rate.

Imaging instability in the athlete: the right modality for the right diagnosis.

The imaging evaluation of an athlete with glenohumeral instability encompasses multiple modalities, including radiography, CT, and MRI. There remains an overall lack of agreement and consistency among the orthopedic community regarding techniques used to quantify glenohumeral bone loss. When a high level of clinical suspicion remains, advanced imaging techniques are strongly recommended to ensure reliable and accurate assessment of defect size and location.

Arthroscopic Repair of Articular Surface Partial-Thickness Rotator Cuff Tears: Transtendon Technique versus Repair after Completion of the Tear—A Meta-Analysis

Articular surface partial-thickness rotator cuff tears (PTRCTs) are commonly repaired using two different surgical techniques: transtendon repair or repair after completion of the tear. Although a number of studies have demonstrated excellent clinical outcomes, it is unclear which technique may provide superior clinical outcomes and tendon healing. The purpose was to evaluate and compare the clinical outcomes following arthroscopic repair of articular surface PTRCT using a transtendon technique or completion of the tear. A systematic review of the literature was performed following PRISMA guidelines and checklist. The objective outcome measures evaluated in this study were the Constant Score, American Shoulder and Elbow Surgeons score, Visual Analogue Scale, physical examination, and complications. Three studies met our criteria. All were prospective randomized comparative studies with level II evidence and published from 2012 to 2013. A total of 182 shoulders (mean age 53.7 years; mean follow-up 40.5 months) were analyzed as part of this study. Both procedures provided excellent clinical outcomes with no significant difference in Constant Score and other measures between the procedures. Both procedures demonstrated improved clinical outcomes. However, there were no significant differences between each technique. Further studies are required to determine the long-term outcome of each technique.

Suture locking of isolated internal locking knotless suture anchors is not affected by bone quality

Purpose The purpose of this study was to evaluate the mechanical performance of different suture locking mechanisms including: i) interference fit between the anchor and the bone (eg, 4.5 mm PushLock, 5.5 mm SwiveLock), ii) internal locking mechanism within the anchor itself (eg, 5.5 mm SpeedScrew), or iii) a combination of interference fit and internal locking (eg, 4.5 mm MultiFIX P, 5.5 mm MultiFIX S). Methods Anchors were tested in foam blocks representing normal (20/8 foam) or osteopenic (8/8 foam) bone, using standard suture loops pulled in-line with the anchor to isolate suture locking. Mechanical testing included cyclic testing for 500 cycles from 10 N to 60 N at 60 mm/min, followed by failure testing at 60 mm/min. Displacement after 500 cycles at 60 N, number of cycles at 3 mm displacement, load at 3 mm displacement, and maximum load were evaluated. Results Comparing 8/8 foam to 20/8 foam, load at 3 mm displacement and maximum load were significantly decreased (P<0.05) with decreased bone quality for anchors that, even in part, relied on an interference fit suture locking mechanism (ie, 4.5 mm PushLock, 5.5 mm SwiveLock, 4.5 mm MultiFIX P, 5.5 mm MultiFIX S). Bone quality did not affect the mechanical performance of 5.5 mm SpeedScrew anchors which have an isolated internal locking mechanism. Conclusion The mechanical performance of anchors that relied, even in part, on interference fit were affected by bone quality. Isolated internal locking knotless suture anchors functioned independently of bone quality. Anchors with a combined type (interference fit and internal locking) suture locking mechanism demonstrated similar mechanical performance to isolated internal locking anchors in osteopenic foam comparing similar sized anchors. Clinical relevance In osteopenic bone, knotless suture anchors that have an internal locking mechanism (isolated or combined type) may be advantageous for secure tendon fixation to bone.

Prosthetic joint and implant contamination caused by Ralstonia pickettii: a report of three cases

We describe three cases of orthopaedic contamination caused by Ralstonia pickettii grown from prosthetic joint and implant material cultures following sonication in the microbiology laboratory. Given the temporal association between the cases, lack of clinical or intra-operative features of infection, growth of the organism in the water bath, and unlikely etiology of Ralstonia as a prosthetic joint or implant pathogen, the bacteria were judged to be contaminants.

Mean Glenoid Defect Size and Location Associated With Anterior Shoulder Instability: A Systematic Review.

Background: There is a strong correlation between glenoid defect size and recurrent anterior shoulder instability. A better understanding of glenoid defects could lead to improved treatments and outcomes. Purpose: To (1) determine the rate of reporting numeric measurements for glenoid defect size, (2) determine the consistency of glenoid defect size and location reported within the literature, (3) define the typical size and location of glenoid defects, and (4) determine whether a correlation exists between defect size and treatment outcome. Study Design: Systematic review; Level of evidence, 4. Methods: PubMed, Ovid, and Cochrane databases were searched for clinical studies measuring glenoid defect size or location. We excluded studies with defect size requirements or pathology other than anterior instability and studies that included patients with known prior surgery. Our search produced 83 studies; 38 studies provided numeric measurements for glenoid defect size and 2 for defect location. Results: From 1981 to 2000, a total of 5.6% (1 of 18) of the studies reported numeric measurements for glenoid defect size; from 2001 to 2014, the rate of reporting glenoid defects increased to 58.7% (37 of 63). Fourteen studies (n = 1363 shoulders) reported defect size ranges for percentage loss of glenoid width, and 9 studies (n = 570 shoulders) reported defect size ranges for percentage loss of glenoid surface area. According to 2 studies, the mean glenoid defect orientation was pointing toward the 3:01 and 3:20 positions on the glenoid clock face. Conclusion: Since 2001, the rate of reporting numeric measurements for glenoid defect size was only 58.7%. Among studies reporting the percentage loss of glenoid width, 23.6% of shoulders had a defect between 10% and 25%, and among studies reporting the percentage loss of glenoid surface area, 44.7% of shoulders had a defect between 5% and 20%. There is significant variability in the way glenoid bone loss is measured, calculated, and reported.

Normal Glenoid Relationships Used for Unilateral Quantification of Glenoid Bone Loss in Glenohumeral Instability

Objectives: Current methods used to quantify glenoid bone loss following anterior shoulder instability rely on bilateral shoulder imaging to obtain normal linear and surface area parameters of the uninjured glenoid fossa. This method is based on the assumption that there is little side-side variability in these anatomical relationships. Previous reports have demonstrated differences in the morphology of the glenoid fossa based on the anterior glenoid notch. The purpose of this study was to determine the normal dimensions of height, width, surface area, and shape of the human glenoid fossa as function of glenoid notch, and to determine if side-to-side differences exist for these parameters. Due to notch variation, we hypothesize that the inferior glenoid fossa is better represented as an ellipse versus a perfect circle as previously described. We also hypothesize that side-to-side differences exist in glenoid surface area. Methods: The authors studied 58 human scapulae pairs between 18 and 35 years of age from the Hamann-Todd Osteological Collection. Age, sex, race, body height and weight were known for each specimen. Paired specimens were sorted into groups of 5 according to race, sex, and notch type. All specimens were digitized using a 3-D laser scanner, with a stated accuracy of 0.005 inches. Height, width, surface area, and notch angle measurements were calculated using software written in the MATLAB platform. A best fit ellipse was applied to the inferior glenoid based on the glenoid circumference below the notch. Differences in surface area of paired glenoids were assessed using a matched pairs T-test. Multiple stepwise linear regression models were created to select predictors of glenoid surface area. Lastly, the intra-rater and inter-rater reliability of the notch classification as reported by Merrill et al. was assessed among 13 raters. Results: The mean height (s.d.) of the glenoid fossae was 35.0 ± 2.8 mm. Inferior width was 24.8 ± 2.5 mm. The best-fit ellipse of the inferior glenoid had a mean eccentricity of 0.425 ± 0.099. The right glenoid, when compared to its left counterpart, had greater overall surface area (x̄right= 679.6 mm2, x̄left= 657.2 mm2, P< 0.0001*) and inferior surface area (x̄right= 548.2 mm2, x̄left= 533.1 mm2, P< 0.0076*). Patient height, sex, and glenoid height correlated with total and inferior glenoid surface area with r2= 0.902 and 0.779, respectively (P< 0.0001*). Analysis of intra-observer reliability showed a consistency of 0.56 (95% CI= 0.26- 0.77), while the inter-observer reliability kappa coefficient was 0.43 (95% CI= 0.41- 0.45). Conclusion: By considering unilateral anatomic relationships of the glenoid fossa, we were able to determine alternative methods of evaluating glenoid bone loss. Glenoid notch angle had moderate reliability and was not considered clinically useful to stratify glenoid morphology. Based on non-zero eccentricity values of the best-fit ellipse, the inferior glenoid fossa did not represent a perfect circle. In addition, side-to-side differences were found between glenoid surface area measurements. The latter two findings contradict assumptions made by current techniques used in clinical practice to calculate bone loss and raise concern as to their validity. Using easily obtainable patient (height and sex) and glenoid (height) parameters, glenoid surface area can be predicted by means of regression modeling, permitting unilateral measurements of glenoid bone loss to be made in clinical practice.

Revision Open Capsular Shift for Atraumatic and Multidirectional Instability of the Shoulder

Shoulder stability is critical for proper functioning of the upper extremity and is dependent on the interplay between static and dynamic stabilizers of the glenohumeral joint. Surgical management of patients with atraumatic and multidirectional instability is effective if the capsular redundancy is properly reconstructed to restore glenohumeral joint biomechanics. Residual capsular laxity is a common cause of recurrent glenohumeral joint dislocation in patients who had previous stabilization procedures; surgical results become less predictable in patients who had multiple revision procedures. It is important to detect capsular laxity at the time of the index surgery and use reliable surgical techniques to obtain optimal results.