A narrative review of little league shoulder: proximal humeral physis widening is only one piece of the puzzle, it is time to consider posterior glenoid dysplasia.

Baseball athletes across all levels of play are at an increased risk for upper extremity injury due to the supraphysiologic demands on the shoulder and elbow during overhead throwing. Little league baseball players present with a unique subset of injuries that can affect the growth plate, commonly at the shoulder or the elbow. Ascertaining a diagnosis and plan of care for little league shoulder (LLS) historically focuses on the proximal humeral physis in skeletally immature throwing athletes presenting with shoulder pain. However, while not a current standard of care, posterior glenoid dysplasia is often present in youth baseball athletes presenting with LLS, warranting a shift in the way clinicians evaluate for and treat the youth baseball athlete's pathologic shoulder. Therefore, purpose of this narrative review is 2-fold: first, to describe the current standard of care as it relates to a diagnosis of LLS, and second, to critically describe a comprehensive evaluation process for youth throwing athletes with shoulder pain that includes screening for evidence of posterior glenoid dysplasia. This paper summarizes the current state of the available evidence for anatomic considerations of LLS in the baseball athletes throwing shoulder. Additionally, we provide a framework for clinical evaluation using a multidisciplinary approach to evaluate the entire kinetic chain of the youth baseball athlete presenting with LLS and posterior glenoid dysplasia. A case study is presented to describe common presentations, clinical and objective examinations, and a plan of care from time of evaluation to return to throwing.

Anatomic shoulder arthroplasty in Walch type C glenoid deformity: mid- to long-term outcomes.

BACKGROUND: Hypoplastic glenoid morphology in the setting of glenohumeral osteoarthritis is a rare yet complex surgical problem. Treatment of this patient population with anatomic total shoulder arthroplasty (aTSA) remains controversial. Furthermore, there is no gold-standard approach, with limited guidance for surgeons on the need for glenoid version correction in the setting of a dysplastic glenoid. The purpose of this study was to evaluate mid- to long-term outcomes and reoperation rates of aTSA for the treatment of primary glenohumeral osteoarthritis with Walch type C glenoid deformity. METHODS: This observational, retrospective cohort study identified patients with a Walch type C glenoid who underwent aTSA at 2 institutions between 2007 and 2016. Patients were contacted to complete updated patient-reported outcome measures at a minimum of 5.5 years postoperatively. The outcome measures collected included the American Shoulder and Elbow Surgeons (ASES) score and Single Assessment Numeric Evaluation (SANE) score. Secondary outcomes included any additional surgical procedures on the operative shoulder, patient satisfaction, and willingness to undergo aTSA again. RESULTS: In total, 30 patients met the inclusion criteria, of whom 26 (86.7%) were able to be contacted to undergo final outcome evaluations. The mean age at the time of surgery was 61.3 years (range, 40.9-75.5 years), and 20 patients (76.9%) were men. The mean follow-up period was 8.5 years (range, 5.5-11.3 years) after surgery. Treatment was performed with an augmented component in 9 patients and with a standard component in 17. Of the 17 patients with non-augmented components, 9 underwent partial correction with asymmetrical reaming, 3 received a mini-inset glenoid component, and 2 had an anteriorly offset humeral component. At final follow-up, patients had a mean ASES score of 83.6 ± 16.7, ASES pain score of 24.7 ± 20.8, SANE score of 80.4 ± 20.9, and patient satisfaction rate of 84.1%. No statistically significant differences in any outcome measure were observed between patients with augmented glenoid components and those with non-augmented glenoid components. One revision to reverse shoulder arthroplasty was performed for instability at 7 years postoperatively after a traumatic dislocation. All patients reported that they would be willing to undergo the same surgical procedure again. DISCUSSION: Despite variance in glenoid reconstructive approach, aTSA provides satisfactory and sustained improvements in patient-reported outcomes in patients with glenoid dysplasia and primary glenohumeral osteoarthritis with a low revision rate at a mean of 8.5 years. Anatomic shoulder arthroplasty should remain a surgical option in patients with Walch type C glenoid deformity.

Biomechanical Analysis of Posterior Open-Wedge Osteotomy and Glenoid Concavity Reconstruction Using an Implant-Free, J-Shaped Iliac Crest Bone Graft.

BACKGROUND: Posterior open-wedge osteotomy and glenoid reconstruction using a J-shaped iliac crest bone graft showed promising clinical results for the treatment of posterior instability with excessive glenoid retroversion and posteroinferior glenoid deficiency. PURPOSE: To evaluate the biomechanical performance of the posterior J-shaped graft to restore glenoid retroversion and posteroinferior deficiency in a cadaveric shoulder instability model. STUDY DESIGN: Controlled laboratory study. METHODS: A posterior glenoid open-wedge osteotomy was performed in 6 fresh-frozen shoulders, allowing the glenoid retroversion to be set at 0°, 10°, and 20°. At each of these 3 preset angles of glenoid retroversion, the following conditions were simulated: (1) intact joint, (2) posterior Bankart lesion, (3) 20% posteroinferior glenoid deficiency, and (4) posterior J-shaped graft (at 0° of retroversion). With the humerus in the Jerk position (60° of glenohumeral anteflexion, 60° of internal rotation), stability was evaluated by measuring posterior humeral head (HH) translation (in mm) and peak translational force (in N) to translate the HH over 25% of the glenoid width. Glenohumeral contact patterns were measured using pressure-sensitive sensors. Fixation of the posterior J-graft was analyzed by recording graft micromovements during 3000 cycles of 5-mm anteroposterior HH translations. RESULTS: Reconstructing the glenoid with a posterior J-graft to 0° of retroversion significantly increased stability compared with a posterior Bankart lesion and posteroinferior glenoid deficiency in all 3 preset degrees of retroversion (P < .05). There was no significant difference in joint stability comparing the posterior J-graft with an intact joint at 0° of retroversion. The posterior J-graft restored mean contact area and contact pressure comparable with that of the intact condition with 0° of retroversion (222 vs 223 mm2, P = .980; and 0.450 vs 0.550 MPa, P = .203). The mean total graft displacement after 3000 cycles of loading was 43 ± 84 µm, and the mean maximal mediolateral graft bending was 508 ± 488 µm. CONCLUSION: Biomechanical analysis of the posterior J-graft demonstrated reliable restoration of initial glenohumeral joint stability, normalization of contact patterns comparable with that of an intact shoulder joint with neutral retroversion, and secure initial graft fixation in the cadaveric model. CLINICAL RELEVANCE: This study confirms that the posterior J-graft can restore stability and glenohumeral loading conditions comparable with those of an intact shoulder.

Total shoulder arthroplasty using an inlay glenoid component for glenoid deficiency: mid- to long-term follow-up of a previously published cohort.

BACKGROUND: The short-term results of total shoulder arthroplasty with an inlay glenoid component performed by a single surgeon in patients with glenoid bone loss have previously been reported. The purpose of this study was to investigate the mid- to long-term clinical and radiographic outcomes of these patients. METHODS: We identified a cohort of patients who underwent total shoulder arthroplasty with an inlay glenoid component performed by a single surgeon between 2010 and 2019 for severe glenoid dysplasia and/or glenoid bone loss. Patients with a minimum of 2 years' follow-up were evaluated regarding preoperative and postoperative range of motion, radiographic findings, visual analog scale pain scores, and Single Assessment Numeric Evaluation scores. RESULTS: Overall, 39 shoulders in 33 patients were treated with an inlay glenoid component for severe glenoid bone loss. Four patients were lost to follow-up, and 1 patient died with a well-functioning implant in place. The final cohort included 34 shoulders in 28 patients (46.4% female patients [13 of 28] and 53.6% male patients [15 of 28]) with a mean age of 66.9 years (range, 58-81 years) and mean follow-up period of 68.3 months. Of the 34 cases, 5 were revision cases. One patient died following 2-year follow-up. Of the shoulders, 10 were classified as Walch type A2, 4 were classified as Walch type B3, and 15 were classified as Walch type C; 5 shoulders were unable to be classified. We observed statistically significant increases in range of motion (forward elevation, 38.1° [P < .001]; external rotation, 18.8° [P < .001]) and improvement in the Single Assessment Numeric Evaluation score (from 26.6 to 81.0, P < .001). Two patients underwent conversion to reverse shoulder arthroplasty at 2.2 and 1.7 years postoperatively. CONCLUSION: Inlay glenoid components provide a low rate of revision and improved clinical and functional outcomes at mid- to long-term follow-up.

Reverse total shoulder arthroplasty in patients with type B2, B3, and type C glenoids: comparable clinical outcome to patients without compromised glenoid bone stock-a matched pair analysis.

BACKGROUND: Primarily posterior bone deficient (dysplastic) (Walch type C) or secondarily eroded (Walch type B2 or B3) glenoids represent a surgical challenge for shoulder arthroplasty. Due to the posteriorly static decentered head, reverse total shoulder arthroplasty (RTSA) is often considered as the treatment of choice. The purpose of this study is to report the clinical and radiographic outcomes, complications and reoperations of RTSA for posteriorly deficient glenoids. MATERIALS AND METHODS: All patients who underwent RTSA for osteoarthritis secondary to underlying glenoid deficiency (Walch type B2, B3 and C) between 2005 and 2018 (study group), were identified from our institutional shoulder arthroplasty database and gender- and age-matched to a cohort of patients with normal glenoid bone stock (control group). Longitudinal pre- and postoperative clinical [Constant-Murley (CS) score, Subjective Shoulder Value (SSV)] and radiographic outcomes were assessed. RESULTS: We included 188 patients (94 in each group). The median follow-up was 43 ± 26 (24-144) months in the study group and 59 ± 32 (24-124) months in the control group. The glenoid deficiency was addressed by using glenoid bone reconstruction. The surgical site complication and revision rate of RTSA in patients with bony deficient glenoids were 17% and 7%. Although glenoid loosening was slightly higher in the study group (5 vs. 2), overall no significant differences were found between the study and control groups in satisfaction scores, preoperative and postoperative absolute and relative Constant scores, complication and revision rates, respectively. CONCLUSION: Reverse total shoulder arthroplasty (RTSA) seems to be a valuable treatment option for patients with primary (dysplasia) or secondary (wear) posterior glenoid deficiency. Although severe glenoid bone loss seems to be a risk factor for glenoid component failure, the overall complication and revision rates as well as clinical and radiographic outcome are comparable to RTSA in patients without compromised glenoid bone stock. LEVEL OF EVIDENCE: Level III: case-control study.

Long-term results after posterior open glenoid wedge osteotomy for posterior shoulder instability associated with excessive glenoid retroversion.

BACKGROUND: Treatment of posterior shoulder instability (PSI) associated with excessive glenoid retroversion is a rare, challenging problem in shoulder surgery. One proposed technique is posterior open wedge glenoid osteotomy to correct excessive glenoid retroversion as described by Scott. However, this operation is rarely performed, and limited long-term outcomes using this approach are available. The goal of this study was to analyze the long-term outcomes of posterior open wedge glenoid osteotomy for PSI associated with excessive glenoid retroversion. METHODS: Six consecutive patients (7 shoulders) with a mean age of 24 years (range 19-34) were treated with posterior open wedge glenoid osteotomy for PSI associated with a glenoid retroversion greater than 15° and followed up clinically and radiographically at a mean age of 15 years (range 10-19). RESULTS: Recurrent, symptomatic PSI was observed in 6 of 7 shoulders (86%). One necessitated revision with a posterior (iliac crest) bone block procedure and was rated as a failure and excluded from functional analysis. One patient rated his result as excellent, 3 as good, 1 as fair, and 1 as unsatisfactory. Mean relative Constant Score (CS%) was unchanged from preoperation to final follow-up (CS% = 72%) and pain did not significantly decrease (Constant Score = 7-10 points; P = .969). The mean Subjective Shoulder Value (SSV) improved postoperatively, but with 6 patients the improvement did not reach statistical significance (SSV = 42%-67%, P = .053) and the total Western Ontario Shoulder Instability Index averaged 30% at the final follow-up. Mean glenoid retroversion of all 7 shoulders was corrected from 20° (range 16°-26°) to 3° (range -3° to +8°) (P = .018). In the 5 shoulders with preoperative static posterior subluxation of the humeral head, the humeral head was not recentered. All 7 shoulders showed progression of glenoid arthritic changes. CONCLUSIONS: Posterior open wedge glenoid osteotomy for PSI associated with excessive glenoid retroversion neither reliably restored shoulder stability nor recentered the joint or prevent progression of osteoarthritis. Alternative treatments for PSI associated with excessive glenoid retroversion have to be developed and evaluated.

Discoid Labral Meniscus Covering Two-Thirds of a Type C Glenoid: A Case Report.

BACKGROUND: Glenoid morphology and dysplasia have been extensively described in conjunction with shoulder arthritis. Dysplastic glenoids have a substantial inherent retroversion, a deficient posteroinferior rim, a short scapular neck, and an inferior inclination of the joint surface. The effect of dysplasia on fracture surgery has not been reported to the same extent. CASE PRESENTATION: A 65-year-old man presented with a proximal humeral fracture. The patient was scheduled for osteosynthesis. The head was deemed unrepairable at the time of surgery and the operative plan changed to replace the proximal humerus. A discoid meniscus-like labral extension covering two-thirds of the glenoid was encountered. This finding covered a dysplastic glenoid. The combination of a fracture and a dysplastic glenoid had not been accounted for and made the reconstruction more difficult. The patient received a reverse total shoulder arthroplasty after perioperative considerations regarding reconstruction. At the 2-month follow up, the patient had a satisfactory clinical outcome, with 90° of flexion and minimal residual pain. CONCLUSION: This case illustrates that elective disorders with dysplasia also present to the fracture team. Careful analysis of preoperative imaging should result in an operative plan taking unexpected findings into account.

Early to midterm outcomes of anatomic shoulder arthroplasty performed on dysplastic glenoids.

BACKGROUND: Treatment of primary osteoarthritis with glenoid dysplasia or Walch type C glenoids remains controversial. There is scant literature available on patient outcomes after anatomic shoulder arthroplasty in patients with Walch type C glenoids. The purpose of this study was to evaluate the outcomes of total shoulder arthroplasty (TSA) for Walch type C dysplastic glenoids with standard (nonaugmented) glenoid components compared with TSA for glenoids with concentric wear and minimal erosion (Walch type A1). We hypothesized that TSA performed for Walch type C dysplastic glenoids with standard glenoid components can reliably produce successful results at short- to midterm follow-up. METHODS: We identified all patients who had primary anatomic TSA performed for osteoarthritis in a prospective shoulder arthroplasty registry collected from 2004 to the present time. Twenty-nine patients met inclusion criteria of a preoperative Walch type C dysplastic glenoid, treatment with TSA using standard (nonaugmented) glenoid components, and a minimum of 2-year clinical follow-up. A matched cohort of 58 patients with a type A1 glenoid and minimum of 2-year clinical follow-up for anatomic shoulder arthroplasty served as the control group. The American Shoulder and Elbow Surgeons (ASES) score, the Single Assessment Numeric Evaluation (SANE), patient satisfaction, complications, and revisions were evaluated in both cohorts. RESULTS: The mean follow-up for this study was 4.5 years (standard deviation, 2.6 years; range, 2-10 years). Baseline measures were not significantly different between the Walch type C dysplastic group and the matched type A1 cohort (all P > .05). Both groups showed significant improvements in ASES, ASES pain, and SANE scores from baseline to the final follow-up (all P < .001). The Walch type C group had no significant differences in ASES score (P = .118), ASES pain (P = .730), or SANE score (P = .168) compared with the matched type A1 cohort. The complication rate of patients with a type C glenoid was 14% (4 of 29) with a 7% (2 of 29) revision rate. Similarly, the complication rate for the A1 matched cohort was 17% (10 of 58) with a 12% (7 of 58) revision rate. Both groups had high patient satisfaction without statistical differences (P = .549). In addition, there were no differences in the rate of radiographic lucencies or Lazarus scores (P = .222). CONCLUSIONS: Anatomic TSA reliably produced clinically significant improvements in pain and function and similar short- to midterm outcomes in patients with Walch type C dysplastic glenoids compared with patients with type A1 glenoids. Anatomic TSA with standard (nonaugmented) glenoid components should remain an option in patients with Walch type C dysplastic glenoids despite emerging treatment options including augmented glenoid components and reverse TSA.

Glenoid retroversion is an important factor for humeral head centration and the biomechanics of posterior shoulder stability.

PURPOSE: Glenoid retroversion is a known independent risk factor for recurrent posterior instability. The purpose was to investigate progressive angles of glenoid retroversion and their influence on humeral head centration and posterior translation with intact, detached, and repaired posterior labrum in a cadaveric human shoulder model. METHODS: A total of 10 fresh-frozen human cadaveric shoulders were investigated for this study. After CT- canning, the glenoids were aligned parallel to the floor, with the capsule intact, and the humerus was fixed in 60° of abduction and neutral rotation. Version of the glenoid was created after wedge resection from posterior and fixed with an external fixator throughout the testing. Specimens underwent three conditions: intact, detached, and repaired posterior labrum, while version of the glenoid was set from + 5° anteversion to - 25° retroversion by 5° increments. Within the biomechanical setup, the glenohumeral joint was axially loaded (22 N) to center the joint. At 0° of glenoid version and intact labrum, the initial position was used as baseline and served as point zero of centerization. After cyclic preloading, posterior translation force (20 N) was then applied by a material testing machine, while start and endpoints of the scapula placed on an X-Y table were measured. RESULTS: The decentralization of the humeral head at glenoid version angles of 5°, 10°, 15°, and 20° of retroversion and 5° of anteversion was significantly different (P < 0.001). Every increment of 5° of retroversion led to an additional decentralization of the humeral head overall by (average ± SD) 2.0 mm ± 0.3 in the intact and 2.0 mm ± 0.7 in the detached labrum condition. The repaired showed significantly lower posterior translation compared to the intact condition at 10° (P = 0.012) and 15° (P < 0.01) of retroversion. In addition, CT measured parameters (depth, diameter, and native version) of the glenoid showed no correlation with angle of dislocation of each specimen. CONCLUSION: Bony alignment in terms of glenoid retroversion angle plays an important role in joint centration and posterior translation, especially in retroversion angles greater than 10°. Isolated posterior labrum repair has a significant effect on posterior translation in glenoid retroversion angles of 5° and 10°. Bony correction of glenoid version may be considered to address posterior shoulder instability with retroversion > 15°.

High incidence of posterior glenoid dysplasia of the shoulder in young baseball players.

BACKGROUND: Rounding of the posterior glenoid rim is observed in young throwing athletes with internal shoulder impingement and is considered developmental dysplasia of the glenoid. The aim of our study was to determine the incidence rate of dysplastic changes of the glenoid within a group of 92 young baseball players. METHODS: The study group included 92 male baseball players, with a mean age of 14.63 years. Of these patients, 30 were diagnosed with Little Leaguer's shoulder and 62 with a painful baseball-throwing shoulder with no abnormal findings on x-ray. The posterior glenoid rim of the affected shoulder was compared with the contralateral nonpainful shoulder, with the 2 following outcomes measured on radiographs obtained using the modified Bernageau imaging method: the distance between the anterior and posterior glenoid rims and the presence or absence of dysplasia of the posterior glenoid rim. RESULTS: The mean distance between the anterior and posterior glenoid rims was significantly shorter in the painful shoulders (mean, 26 mm) than in the nonpainful shoulders (mean, 29 mm; P < .0001). Dysplasia of the posterior glenoid rim was identified in 89 painful shoulders (96.7%), with 9 cases (9.7%) identified on the unaffected contralateral side (P < .001). The presence of dysplasia was not correlated with the age at which baseball playing began. CONCLUSION: The incidence of dysplasia of the posterior glenoid rim is high (96.7%) among young baseball players with a painful shoulder. The identified dysplasia may be related to impaired development of the inferior peripheral secondary glenoid ossification center due to repetitive throwing.

Etiology of Shoulder Arthritis in Young Patients.

The manifestation of glenohumeral arthritis in the young adult is a devastating occurrence that can be difficult to manage. This review details the many underlying etiologies including genetic causes, congenital abnormalities, glenohumeral instability, posttraumatic lesions, postcapsulorraphy arthropathy, osteonecrosis, intraarticular pain pump postoperative use, radiofrequency/thermal capsulorraphy treatments, septic arthritis/infection, and inflammatory arthropathies. Although each of these potential causes have been well-studied, their contributions to the development of glenohumeral arthritis in the young person has not been described extensively.

Shoulder Arthroplasty for Sequelae of Obstetrical Brachial Plexus Injury.

PURPOSE: Shoulder arthroplasty following obstetrical brachial plexus injury (OBPI) is technically challenging because glenoid morphology, muscle balance, and humeral version are substantially altered compared with the neurologically intact shoulder. The purpose of this study is to report the outcome of shoulder arthroplasty in a group of patients with end-stage arthritis secondary to OBPI. MATERIALS AND METHODS: Seven patients with OBPI and secondary glenohumeral arthritis were treated with shoulder arthroplasty between 1976 and 2014. Two underwent hemiarthroplasty (HA), 2 underwent total shoulder arthroplasty (TSA), and 3 underwent reverse shoulder arthroplasty (RSA). One HA was lost to follow-up and was excluded. The remaining 6 patients (mean age, 62.5 years old at the time of surgery) were followed for a minimum of 2 years (mean, 7.5 years; range, 2-13 years) Outcome measures included pain, range of motion, and postoperative modified Neer ratings. RESULTS: Pain improved in all shoulders. Mean forward flexion was unchanged. No shoulders treated with HA/TSA regained forward elevation above 90°, compared with 1 out of the 3 RSAs. External rotation improved from a mean of -10° to 20°. Active internal rotation decreased from L1 to L5. Immediate postoperative radiographs showed either severe posterior or posterosuperior subluxation in all 3 patients treated with nonconstrained implants. CONCLUSIONS: Shoulder arthroplasty is an acceptable option to relieve pain in patients with symptomatic shoulder arthritis as a sequel of OBPI. However, range of motion improvements are not expected. TYPE OF STUDY /LEVEL OF EVIDENCE: Therapeutic V.

Guidelines for humeral subluxation cutoff values: a comparative study between conventional, reoriented, and three-dimensional computed tomography scans of healthy shoulders.

BACKGROUND: The humeral subluxation index (HSI) is frequently assessed on computed tomography (CT) scans in conditions of the shoulder characterized by humeral displacement. An arbitrarily set HSI cutoff value of 45% for anterior subluxation and 55% for posterior subluxation has been widely accepted. We studied whether mean values and thresholds of humeral subluxation, in relation to the glenoid and scapula, were influenced by different imaging modalities. METHODS: The HSIs referenced to the scapula (SHSI) and glenoid (GHSI) were compared between conventional CT scans, CT scans reoriented into the corresponding reference plane (ie, scapular plane for the SHSI and glenoid center plane for the GHSI), and 3-dimensional (3D) CT reconstructions of 120 healthy shoulders. The 95% normal range determined the cutoff values of humeral subluxation. RESULTS: The SHSI thresholds for conventional, reoriented, and 3D CT scans were 33%-61%, 44%-68%, and 49%-61%, respectively. A different mean SHSI was found for each imaging modality (conventional, 47%; reoriented, 56%; 3D, 55%; P ≤ .014), with the conventional SHSI showing an underestimation in 89% of the cases. GHSI thresholds for conventional, reoriented, and 3D CT scans were 40%-61%, 44%-56%, and 46%-54%, respectively. The mean GHSI did not differ between each imaging modality (conventional, 51%; reoriented, 50%; 3D, 50%; P = .146). CONCLUSIONS: The SHSI and GHSI are susceptible to different imaging modalities with consequently different cutoff values. The redefined HSI cutoff values guide physicians in the evaluation of humeral subluxation in conditions characterized by humeral displacement, depending on the available image data.

Arthroscopic treatment of posterior shoulder instability in patients with and without glenoid dysplasia: a comparative outcomes analysis.

BACKGROUND: The purpose of this study was to evaluate the influence of glenoid dysplasia on outcomes after isolated arthroscopic posterior labral repair in a young military population. METHODS: Thirty-seven male patients who underwent arthroscopic posterior labral repair for symptomatic posterior shoulder instability were evaluated at a mean duration of 3.1 years. A comparative analysis was performed for those with glenoid dysplasia and without dysplasia. Additional factors analyzed included military occupational specialty (MOS), preoperative mental health clinical encounters and mental health medication use, and radiographic characteristics (version, posterior humeral head subluxation, and posterior capsular area) on a preoperative standard shoulder magnetic resonance arthrogram. The groups were analyzed with regard to shoulder outcome scores (subjective shoulder value [SSV], American Shoulder and Elbow Surgeons [ASES] rating scale, Western Ontario Shoulder Instability Index [WOSI]), need for revision surgery, and medical separation from the military. RESULTS: Of 37 patients, 3 (8.1%) underwent revision surgery and 6 (16%) underwent medical separation. Overall outcome assessment demonstrated a mean SSV of 67.9 (range, 25-100) ± 22.1, mean ASES of 65.6 (range, 15-100) ± 22, and mean WOSI of 822.6 (range, 5-1854) ± 538. There were no significant differences in clinical outcome scores between the glenoid dysplasia and no dysplasia groups (SSV, P = .55; ASES, P = .57; WOSI, P = .56). MOS (P = .02) and a history of mental health encounters (P = .04) were significantly associated with diminished outcomes. CONCLUSIONS: The presence or absence of glenoid dysplasia did not influence the outcome after arthroscopic posterior labral repair in a young military population. However, a history of mental health clinical encounters and an infantry MOS were significantly associated with poorer clinical outcomes.

Glenoid hypoplasia.

Glenoid hypoplasia, also known as glenoid dysplasia and dysplasia of the scapular neck, is a failure of ossification of the posteroinferior two-thirds of the glenoid. Once thought to be a rare condition, more recent studies have shown that the incidence of glenoid hypoplasia ranges from 18% to 35%. This case report and literature review highlights the typical clinical presentation, the radiologic findings, and the management options for patients with glenoid hypoplasia.

Critical Findings on Magnetic Resonance Arthrograms in Posterior Shoulder Instability Compared With an Age-Matched Controlled Cohort.

BACKGROUND: Posterior shoulder instability is less common and potentially more difficult to diagnose clinically and radiographically compared with anterior shoulder instability. Radiographic findings including posterior labral tears, increased retroversion, presence of glenoid dysplasia, and increased capsular area are associated with symptomatic recurrent posterior shoulder instability. PURPOSE: This study aimed to determine the prevalence and severity of associated radiographic parameters found on magnetic resonance arthrograms (MRAs) in patients with arthroscopically confirmed isolated posterior labral tears and symptomatic recurrent posterior shoulder instability, compared with an age-matched cohort of patients without posterior instability or labral injury confirmed with shoulder arthroscopy. STUDY DESIGN: Cross-sectional study, Level of evidence, 3. METHODS: Patients who received a preoperative standard shoulder MRA at an academic institution over a 5-year period and had symptomatic posterior instability and received a repair of an arthroscopically confirmed posterior labral tear (n = 63) were identified. These patients were compared with an age-matched control group of patients without posterior instability (n = 49) who underwent an isolated arthroscopic distal clavicle resection that included an arthroscopic glenohumeral joint evaluation. Glenoid version, posterior humeral head subluxation, glenoid dysplasia, and linear and capsular area measurements were evaluated between the 2 groups. Interobserver reliability for continuous and categorical variables was assessed for all measurements. RESULTS: Multivariate logistic regression revealed that the presence of increased glenoid retroversion (P = .0018), glenoid dysplasia (P = .03), and increased axial posterior capsular cross-sectional area (P = .05) were significantly associated with posterior labral tears and symptomatic posterior shoulder instability compared with the age-matched control group. Posterior humeral head subluxation was found to be a statistically significant variable with univariate analysis (P = .001) for posterior shoulder instability but not with multivariate logistic regression (P = .53). Interobserver reliability was good to very good for all measurements (intraclass correlation coefficient [ICC] = 0.74-0.85; κ = 0.64) but was moderate for total capsular area and sagittal capsular area measurements (ICC = 0.43-0.56). CONCLUSION: The presence of increased glenoid retroversion, glenoid dysplasia, and increased posterior capsular area on MRA are significantly associated with posterior labral tears and symptomatic posterior shoulder instability. Identification of these critical radiographic variables on magnetic resonance arthrography assists in the accurate diagnosis and management of clinically significant posterior shoulder instability.

Surgical options for the young patient with glenohumeral arthritis.

Young patients with glenohumeral arthritis are an ongoing treatment challenge. They typically have high demands of their shoulders, require long-term durability due to their young age, and often have altered local anatomy, through their disease process (instability arthropathy, juvenile rheumatoid arthritis, etc.) or from previous surgery (capsulorraphy arthropathy, chondrolysis, etc.). Workup to evaluate underlying causes of early arthritis, and to exclude infectious causes are necessary. When nonoperative management fails, arthroscopic debridement, hemiarthroplasty (isolated, with glenoid reaming, or with biological interposition), and total shoulder arthroplasty are treatment options available to the treating surgeon. Debridement or hemiarthroplasty can provide pain relief for a subset of patients, but results have not been reproducible across the literature and have not been durable over time. Total shoulder arthroplasty provides the most reliable pain relief, but long-term glenoid loosening and wear continue to lead to high revision rates in this patient population.

Total shoulder arthroplasty using an inlay mini-glenoid component for glenoid deficiency: a 2-year follow-up of 9 shoulders in 7 patients.

BACKGROUND: Glenoid bone loss and severe retroversion can pose difficulties when implanting a glenoid component for total shoulder arthroplasty for primary osteoarthritis. Mini-glenoid implants may be useful in the setting of severe glenoid wear in which a standard pegged glenoid component cannot be placed. MATERIALS AND METHODS: This study is a retrospective review, performed over a 3-year period, of patients who received a total shoulder arthroplasty using an inset mini-glenoid in the setting of severe glenoid dysplasia and/or medial glenoid bone loss. We identified patients with a minimum of 2 years' follow-up and evaluated preoperative and postoperative range of motion, visual analog scale scores, Single Assessment Numeric Evaluation scores, complications, and patient satisfaction. RESULTS: Seven patients (4 female and 3 male patients; 9 shoulders) with a mean age of 66 years were treated with the described procedure and had a mean follow-up of 34 months. There were 6 primary arthroplasties and 3 revision cases. Four shoulders were classified as Walch type A2 glenoids, 2 were classified as Walch type C, and 3 were unable to be classified. There was a statistically significant increase in range of motion (forward elevation, 48°; external rotation, 14°), decrease in pain scores (8 points to 1 point), and improvement in Single Assessment Numeric Evaluation scores (31.7% to 89.4%). The mean patient satisfaction score was 8.6 points on a 10-point scale. CONCLUSION: At 2-year follow-up, total shoulder arthroplasty with a mini-glenoid component can offer adequate pain relief and functional results in the setting of glenoid bone loss or severe retroversion.

Glenoid retroversion: The palaeopathological perspective.

Retroversion of the glenoid articular plane has not received sufficient attention in palaeopathological studies. Occasionally mentioned in severe forms of osteoarthritis, exceptionally studied in extreme congenital forms isolated or in the context of malformation syndromes and overlooked in cases of minor dysplasia, it is nonetheless a valuable marker for identifying debilitating pathological conditions, abnormal shoulder laxity or sequelae of obstetric palsy. It is sometimes associated with other anomalies of the shoulder, the acromion or the coracoid processes of the scapula or the proximal end of the humerus. In this contribution, we first define a new method for measuring glenoid retroversion based on recent embryological and anatomical findings. This new method is particularly well adapted to archaeological remains for its simplicity and the possibility of using it with very fragmentary scapulae. We then applied it to eight pathological cases of various origins, dysplasias or acquired forms of glenoid retroversion; semiological analysis enabled the definition of diagnostic criteria for the main aetiologies. Several new diagnostic features are described, in particular for sequelae of obstetric palsy in adults.