scholarly journals The Influence of Glenoid Retroversion on Posterior Shoulder Instability: A Cadaveric Study (214)

2021 ◽  
Vol 9 (10_suppl5) ◽  
pp. 2325967121S0032
Author(s):  
James Levins ◽  
Rohit Badida ◽  
Edgar Garcia-Lopez ◽  
Steven Bokshan ◽  
Steven DeFroda ◽  
...  

Objectives: Increased glenoid retroversion has been associated with an increased risk of posterior glenohumeral instability. Normal mean glenoid version is between 0-7° of retroversion depending on the population and measurement method. Retroversion can range above 20°, notably in patients with glenoid dysplasia. Increased glenoid retroversion has also been proposed as a risk factor for failure after primary soft tissue repair. Arthroscopic repair is the most common surgical treatment; however, this does not address cases of increased glenoid retroversion. What has not been identified is the degree of glenoid retroversion associated with recurrent instability or failed repair. The goal of our work is to (1) measure how resistance to posterior translation changes as retroversion increases, (2) examine if labral tear results in a greater decrease to resistance at increasing degrees of retroversion, and (3) to determine the degree of retroversion at which labral repair fails to restore the resistance of the intact, neutral version state. Methods: Eight fresh frozen cadaveric shoulder specimens (age 50-64, 4 male) were prepared, maintaining bone and capsulolabral tissue. The scapula and humerus were potted using quick-set polyurethane. CT scans were obtained to establish a scapular 3D coordinate system relative to the potting. Specimens were mounted on a 6 degree of freedom musculoskeletal simulation robotic arm (KUKA KR 6 R700, Augsburg, Germany) and referenced to the coordinate system. The humeral head was centered on the glenoid using a 50N compressive force, and the humerus was translated posterior-inferiorly (30° inferior to the midline) at 1mm/sec in neutral rotation for 10mm. The shoulder was positioned in 30° of abduction and 30° of flexion, based on prior protocol. Custom simVITRO (Cleveland Clinic, Ohio, US) labview-based control software measured peak resistance at 0° of version and then in 5° increments of retroversion until the specimen dislocated, up to 30° of retroversion. Version was adjusted through use of a multiplanar vice. A posterior labral tear was created from the 2 to 6 o’clock position on a left shoulder, and the same testing parameters were performed. Vertical mattress sutures using 4 independent bone tunnels were used to repair the labrum and the same version iterations were tested. Generalized estimating equations were used to compare the peak resistance to translation for each degree of version in the intact, cut and repaired states. The maximum likelihood estimators of the model were adjusted for any model misspecification using classical sandwich estimation. Post hoc pairwise comparisons between conditions were conducted via orthogonal contrasts. The Holm-test was used to calculate adjusted p-values and confidence intervals. Statistical significance was established at the P<0.05 level and all interval estimates were calculated for 95% confidence. Results: The mean peak resistance for the intact labral state decreased significantly for each interval increase in retroversion when the humerus was translated posterior-inferiorly (Figure 1). On average, a 1° increase in retroversion correlated with a 3.5% decrease in resistance to translation. Dislocation with an intact labrum without any posterior force occurred at a mean of 22.7° (range 15-30°) of retroversion. After labral tear, resistance forces to posterior-inferior translation decreased but not significantly from the intact state. However, the percent change of resistance force decreased 41% at 25° of retroversion; this was notably higher than the percent change at 0-15° of retroversion (range 2.7-6.5% decrease) but was not statistically significant (Figure 2). Compared to the intact state at 0° version, there was a 45% and 81% decrease in resistance after labral repair at 20° and 25° of retroversion, respectively (p=0.04 and p=0.004). Conclusions: Glenoid retroversion has a significant effect on resistance to posterior humeral head translation, with each degree increase accounting for 3.5% of resistance to translation. Cutting the labrum at 0-15° of retroversion does not have a significant effect on resistance to posterior inferior humeral translation; however, at 25° of retroversion cutting the labrum results in a 41% decrease in resistance. Similarly, labral repair at 20-25° of retroversion does not recreate peak resistance values of the intact state at 0-5° of retroversion. These findings point to the bony anatomy (retroversion) playing a larger role in preventing posterior instability than the labrum. It also provides evidence that the labrum plays a more significant role in stability at higher degrees of retroversion, and labral repair in patients with >20° of retroversion may be subjected to a relatively greater percentage of force than those at lesser degrees of retroversion.

2020 ◽  
Vol 185 (9-10) ◽  
pp. e1556-e1561
Author(s):  
Daniel L Christensen ◽  
Michael J Elsenbeck ◽  
Jared A Wolfe ◽  
Walter N Nickel ◽  
William Roach ◽  
...  

Abstract Introduction There are no reports in the literature describing risk factors for failure of nonoperative treatment of patients with posterior labral tears on magnetic resonance imaging (MRI). The purpose of this study is to identify risk factors for failure of nonoperative treatment in patients with an isolated posterior glenoid labral tear identified on MRI only. Patients with posterior labral tears on MRI who fail to improve with nonoperative treatment likely share a constellation of clinical history, physical exam, and radiographic findings. Methods One hundred and fifty-nine active duty military service members under the age of 40 with a posterior labral tear seen on MRI and who were clinically evaluated by a musculoskeletal trained physician were identified. We retrospectively evaluated their records ensuring a minimum of 2 years follow-up after MRI to identify surgical intervention for the posterior labral tear during this time period. Patients were stratified into two groups, those treated with any combination of nonoperative modalities and those treated with posterior labral repair surgery during the 2 years after the MRI. The electronic medical records were reviewed for clinical presentation and physical exam results. We measured multiple radiographic parameters, including glenoid version, size of the tear, and bone loss on MRI. Qualitative and quantitative data were compared between groups using Fisher’s exact test and Student’s t-test, respectively. This study was conducted under institutional review board approval. Results Of the 157 patients’ shoulders in our study, 52% (n = 82) of patients with posterior labral tears underwent nonoperative treatment while 48% (n = 75) underwent surgery. The significant risk factors associated with surgery were a history of a specific injury, primary presenting complaint of instability, patient reported history of subluxation, inability to trust their shoulder with overhead activity, decreased strength with weight lifting, positive posterior load/shift exam, positive anterior apprehension, increased osseous glenoid retroversion, increased humeral head subluxation ratio, and anterior labral height (P &lt; 0.05). Patients with a chief complaint of pain were much more likely to succeed with nonoperative treatment while those with instability underwent surgery more often. Ten (12.5%) of the surgical procedures included an anterior and posterior labral repair/stabilization procedure. Conclusion Patients with an MRI confirmed posterior labral tear, which present with subjective complaints and physical exam maneuvers consistent with instability, appear less likely to be treated nonoperatively. Increased glenoid retroversion and posterior humeral head subluxation may also predispose patients toward surgical treatment. Additionally, posterior labral tears may extend into the anterior labrum more frequently than is recognized on MRI.


SLEEP ◽  
2021 ◽  
Vol 44 (Supplement_2) ◽  
pp. A51-A51
Author(s):  
Huan Yang ◽  
Michael Vazquez ◽  
Monika Haack ◽  
Janet Mullington

Abstract Introduction Insufficient sleep is associated with an increased risk of hypertension. It is well established that long-term BP regulation is modulated by the renin-angiotensin-aldosterone system (RAAS) and chronic kidney disease is a strong independent risk factor for development of cardiovascular disease. This study investigated the biomarkers of RAAS and renal function during repetitive exposures to controlled, experimental sleep restriction (SR). We hypothesized an upregulation of RAAS and increased markers of impaired renal function. Methods Twenty-one healthy participants (11 women, average age 31±2 years) completed the 22-day in-hospital SR protocol: permitted 4h of sleep/night from 0300-0700 for 3 nights followed by a recovery sleep, repeated 4 times. Blood samples were collected and plasma renin activity (PRA) was assessed in the morning (7:05am) and in the evening before bedtime (22:45pm) at baseline, experimental days (3rd day of each of the 4 blocks), and recovery. Urinary albumin to creatinine ratio (ACR) was measured from 24-h urinary collection at baseline, first and fourth SR blocks. Estimated glomerulus filtration rate (eGFR) was calculated based on the serum cystatin C levels at baseline and last block of SR. Results Percent change of evening PRA significantly increased during 4 blocks of SR and recovery (SR effect p=0.039), but not morning PRA (SR effect p=0.34). Specifically, evening PRA increased up to 98.4% in the first (p&lt;0.01), 61.3% in the second (p=0.04) SR blocks, and 57.5% (p=0.05) in recovery. Urinary ACR showed no significant changes during first or fourth SR blocks (SR effect p=0.28). In addition, eGFR did not change in the fourth SR block compared to BL (paired t-test, p=0.27). Conclusion We did not see increased markers of impaired renal function (ACR or eGFR). Rather, short-term repetitive exposures to SR significantly increased percent change of PRA measured before bedtime, and evening PRA did not return to BL level during recovery. Our results suggested that sleep deficiency may contribute to hypertension through upregulation of RAAS during wake time. Support (if any) SRSF (CDA to Huan Yang), NIH (R01HL106782 to Dr. Janet Mullington), Harvard Catalyst, Harvard Clinical and Translational Science Center (UL1TR001102).


2021 ◽  
Vol 9 (7_suppl4) ◽  
pp. 2325967121S0024
Author(s):  
Michael Kucharik ◽  
Paul Abraham ◽  
Mark Nazal ◽  
Nathan Varady ◽  
Wendy Meek ◽  
...  

Objectives: Acetabular labral tears distort the architecture of the hip and result in accelerated osteoarthritis and increases in femoroacetabular stress. Uncomplicated tears with preserved, native fibers can be fixed to acetabular bone using labral repair techniques, which have shown improved outcomes when compared to the previous gold standard, labral debridement and resection. If the tear is complex or the labrum is hypoplastic, labral reconstruction techniques can be utilized to add grafted tissue to existing, structurally intact tissue or completely replace a deficient labrum. The ultimate goal is to reconstruct the labrum to restore the labral seal and hip biomechanics. Clinical outcomes using autografts and allografts from multiple sources for segmental and whole labral reconstruction have been reported as successful. However, reconstruction using autografts has been associated with substantial donor-site morbidity. More recently, all-arthroscopic capsular autograft labral reconstruction has been proposed as a way to repair complex or irreparable tears without the downside of donor-site morbidity. Since all-arthroscopic capsular autograft labral reconstruction is a novel technique, there is limited data in the literature on patient outcomes. The purpose of this study is to report outcomes in patients who have undergone this procedure at a minimum 2-year follow-up. Methods: This is a retrospective case series of prospectively collected data on patients who underwent arthroscopic acetabular labral repair by a senior surgeon between December 2013 and May 2017. Patients who failed at least 3 months of conservative therapy and had a symptomatic labral tear on magnetic resonance angiography (MRA) were designated for hip arthroscopy. The inclusion criteria for this study were adult patients age 18 or older who underwent arthroscopic labral repair with capsular autograft labral reconstruction and completion of a minimum 2-year follow-up. Intraoperatively, these patients were found to have a labrum with hypoplastic tissue (width < 5 mm), complex tearing, or frank degeneration of native tissue. Patients with lateral center edge angle (LCEA) ≤ 20° were excluded from analysis. Using the patients’ clinical visit notes with detailed history and physical exam findings, demographic and descriptive data were collected, including age, sex, laterality, body mass index (BMI), and Tönnis grade to evaluate osteoarthritis. Patients completed patient-reported outcome measures and postoperatively at 3 months, 6 months, 12 months, and annually thereafter. Results: A total of 72 hips (69 patients) met inclusion criteria. No patients were excluded. The cohort consisted of 37 (51.4%) male and 35 (48.6%) female patients. The minimum follow-up was 24 months, with an average follow-up of 30.3 ± 13.2 months (range, 24-60). The mean patient age was 44.0 ± 10.4 years (range 21-64), with mean body mass index of 26.3 ± 4.3. The cohort consisted of 6 (8.3%) Tönnis grade 0, 48 (66.7%) Tönnis grade 1, and 18 (25.0%) Tönnis grade 2. Two (2.8%) progressed to total hip arthroplasty. Intraoperatively, 5 (6.9%) patients were classified as Outerbridge I, 14 (19.4%) Outerbridge II, 45 (62.5%) Outerbridge III, and 8 (11.1%) Outerbridge IV. Seventy-two (100.0%) patients had a confirmed labral tear, 34 (47.2%) isolated pincer lesion, 4 (5.6%) isolated CAM lesion, and 27 (37.5%) had both a pincer and CAM lesion. The mean of differences between preoperative and 24-month postoperative follow-up PROMs was 22.5 for mHHS, 17.4 for HOS-ADL, 32.7 for HOS-Sport, 22.9 for NAHS, 33.9 for iHOT-33. (Figure 1) The mean of differences between preoperative and final post-operative follow-up PROMs was 22.1 for mHHS, 17.6 for HOS-ADL, 33.2 for HOS-Sport, 23.3 for NAHS, and 34.2 for iHOT-33. (Table 1) Patient age and presence of femoroacetabular impingement were independently predictive of higher postoperative PROM improvements at final follow-up, whereas Tönnis grade was not. (Table 2) The proportion of patients to achieve the minimally clinically important difference (MCID), substantial clinical benefit (SCB), and patient acceptable symptom state (PASS) thresholds were also calculated. (Table 3) Conclusions: In this study of 72 hips undergoing arthroscopic labral repair with capsular autograft labral reconstruction, we found excellent outcomes that exceeded the MCID thresholds in the majority of patients at an average 30.3 months follow-up. When compared to capsular reconstruction from autografts and allografts, this technique offers the potential advantages of minimized donor-site morbidity and fewer complications, respectively. [Table: see text][Table: see text][Table: see text]


Author(s):  
Guillaume D. Dumont ◽  
Matthew J. Pacana ◽  
Adam J. Money ◽  
Thomas J. Ergen ◽  
Allen J. Barnes ◽  
...  

AbstractFemoroacetabular impingement syndrome (FAIS) is commonly associated with acetabular labral tears. Correction of impingement morphology and suture anchor repair of labral tears have demonstrated successful early and midterm patient-reported outcomes. The purpose of this study was to evaluate the posterior and anterior extent and size of labral tears in patients with FAIS undergoing arthroscopic labral repair, and to evaluate the number of suture anchors required to repair these tears. The design of this study was retrospective case series (Level 4). A single surgeon's operative database was retrospectively reviewed to identify patients undergoing primary arthroscopic hip labral repair between November 2014 and September 2019. Patient-specific factors and radiographic measurements were recorded. Arthroscopic findings including labral tear posterior and anterior extents, and the number of suture anchors utilized for the repair were recorded. Linear regression was performed to identify factors associated with labral tear size. The number of suture anchors used relative to labral tear size was calculated. Three-hundred and thirteen patients were included in the study. The mean posterior and anterior extent for labral tears were 11:22 ± 52 and 2:20 ± 34 minutes, respectively. Mean tear size was 2 hours, 58 minutes ± 45 minutes. The mean number of suture anchors utilized for labral repair was 3.1 ± 0.7. The mean number of anchors per hour of labral tear was 1.1 ± 0.3. Increased age, lateral center edge angle, and α angle were associated with larger labral tears. Our study found that acetabular labral tears associated with FAIS are, on average, 3 hours in size and centered in the anterosuperior quadrant of the acetabulum. Arthroscopic labral repair required 1.1 anchors per hour of tear size, resulting in a mean of 3.1 anchors per repair. Level of Evidence IV


Author(s):  
Ismail Cem Sormaz ◽  
Ahmet Yalin Iscan ◽  
Ilker Ozgur ◽  
Seyma Karakus ◽  
Fatih Tunca ◽  
...  

Background: To investigate the impact of the percent change of postoperative parathormone (PoPTH) level from baseline value (∆PTH) on the rate of hypocalcemia after total thyroidectomy. Methods: Assays of serum PTH and calcium (Ca) were performed preoperatively and at 24 hours postoperatively in 222 consecutive patients who underwent total thyroidectomy. Postoperative hypocalcemia was defined as serum calcium level corrected for albumin concentration (cCa) &lt;8.5mg/dl. Patients with postoperative hypocalcemia were classified as group1 (n=100) and those with normal Ca levels as group 2 (n=122). The PoPTH levels and ∆PTH were compared between the two groups. ROC analysis was performed to determine the cut off values for PoPTH and ∆PTH. Results: The mean PoPTH level was significantly lower in group 1 compared to group 2 (18.6±15.3 pg/ml vs 32.3±15.6 pg/ml, respectively; P&lt;0.0001). PoPTH values were within normal range in 54% of the patients with hypocalcemia and 35% of those with symptomatic hypocalcemia. PoPTH &lt;28pg/ml or ∆PTH &gt;45 were significantly associated with increased risk of post-thyroidectomy hypocalcemia (P=0.0001). A ∆PTH &gt;70% ,PoPTH ≤ 15.5pg/ml and postoperative serum cCa concentrations&lt;8.0mg/dl significantly predicted symptomatic hypocalcemia(P=0.009;P=0.006;andP=0.0001;respevtively).The sensitivities of ∆PTH,PoPTH level and postoperative serum cCa concentration to predict symptomatic hypocalcemia were 67%,64% and100, respectively. Conclusion: Although, PTH decline significantly correlate with symptomatic hypocalcemia, a considerable number of patients may experience hypocalcemic symptoms in spite of normal PoPTH levels. Analysis of serum Ca concentrations at 24 hours postoperatively help to achieve a more precise prediction of patients who bear a high risk for developing hypocalcemic symptoms.


2020 ◽  
Author(s):  
Makoto Kawai ◽  
Kenji Tateda ◽  
Yuma Ikeda ◽  
Ryosuke Motomura ◽  
Ima Kosukegawa ◽  
...  

Abstract Background: Arthroscopic labral repair is an effective treatment for femoroacetabular impingement (FAI) and acetabular labral injury. However, the effectiveness of physiotherapy treatment is controversial. Previous studies that analyzed the outcome of physiotherapy for patients with FAI or acetabular labral tears did not consider damaged tissues or the severity of the acetabular labral tear. This study aimed to evaluate (1) the short-term outcome of physiotherapy in patients with acetabular labral tears confirmed by magnetic resonance imaging (MRI) and (2) the effectiveness of physiotherapy according to the severity of the labral tear.Methods: Thirty-five patients who underwent physiotherapy for symptomatic acetabular labral tears from August 2013 to July 2018 were enrolled. We evaluated the severity of the acetabular labral tears, which were classified based on the Czerny classification system using 3-T MRI. Clinical findings of microinstability and extra-articular pathologies of the hip joint were also examined. Outcome scores were evaluated using the International Hip Outcome Tool 12 (iHOT12) at pre- and post-intervention.Results: The mean iHOT12 score significantly improved from 44.0 to 73.5 in 4.7 months. The post-intervention iHOT12 scores were significantly higher than the pre-intervention scores at stages I (pre 51.0, post 74.4; P=0.004) and II (pre 44.8, post 81.2; P<0.001). However, there were no significant differences between the pre-intervention and post-intervention iHOT12 scores at stage III (pre 36.6, post 60.8; P=0.061). Furthermore, 7 patients (20.0%) had positive microinstability tests, and 22 (62.9%) had findings of extra-articular pathologies. Of 35 patients, 8 (22.9%) underwent surgical treatment after failure of conservative management, of whom 4 had Czerny stage III.Conclusions: Physiotherapy significantly improved the iHOT12 score of patients with acetabular labral tears in the short-term period. In patients with severe acetabular labral tear, improvement of clinical score by physiotherapy may be poor. Identifying the severity of acetabular labral tears can be useful in determining treatment strategies.


2020 ◽  
Vol 48 (11) ◽  
pp. 2621-2627
Author(s):  
Jared A. Wolfe ◽  
Michael Elsenbeck ◽  
Kyle Nappo ◽  
Daniel Christensen ◽  
Robert Waltz ◽  
...  

Background: Posterior glenohumeral instability is an increasingly recognized cause of shoulder instability, but little is known about the incidence or effect of posterior glenoid bone loss. Purpose: To determine the incidence, characteristics, and failure rate of posterior glenoid deficiency in shoulders undergoing isolated arthroscopic posterior shoulder stabilization. Study Design: Cohort study; Level of evidence, 3. Methods: All patients undergoing isolated posterior labral repair and glenoid-based capsulorrhaphy with suture anchors between 2008 and 2016 at a single institution were identified. Posterior bone deficiency was calculated per the best-fit circle method along the inferior two-thirds of the glenoid by 2 independent observers. Patients were divided into 2 groups: minimal (0%-13.5%) and moderate (>13.5%) posterior bone loss. The primary outcome was reoperation for any reason. The secondary outcomes were military separation and placement on permanent restricted duty attributed to the operative shoulder. Results: A total of 66 shoulders met the inclusion criteria, with 10 going on to reoperation after a median follow-up of 16 months (range, 14-144 months). Of the total shoulders, 86% (57/66) had ≤13.5% bone loss and 14% (9/66) had >13.5%. Patients with moderate posterior glenoid bone loss had significantly greater retroversion (−11.5° vs −4.3°; P = .01). Clinical failure requiring reoperation was seen in 10.5% of patients in the minimal bone deficiency group and 44.4% in the moderate group ( P = .024). There was no difference between groups in rate of military separation or restricted duty. Patients with moderate posterior glenoid bone deficiency were more likely to be experiencing instability instead of pain on initial presentation ( P < .001), were more likely to have a positive Jerk test result ( P = .05), and had increased glenoid retroversion ( P = .01). Conclusion: In shoulders with moderate glenoid bone deficiency (>13.5%) and increased glenoid retroversion, posterior capsulolabral repair alone may result in higher reoperation rates than in shoulders without bone deficiency.


2004 ◽  
Vol 16 (5) ◽  
pp. 1-5 ◽  
Author(s):  
J. A. van der Sluijs ◽  
W. J. R. van Ouwerkerk ◽  
R. A. Manoliu ◽  
P.I. J. M. Wuisman

Object The authors performed a prospective study in which magnetic resonance (MR) imaging was conducted in 26 consecutive infants (mean age 5.6 months, range 2.7–14.5 months) in whom recovery from an obstetric lesion of the brachial plexus had been inadequate in the first 3 months of life. The purpose was to identify early secondary deformations of the shoulder in obstetrical brachial plexus lesions (OBPLs). Methods Features of the shoulders were analyzed according to a standardized MR imaging protocol in patients with OBPLs. Measurements were made of the appearance of the glenoid, glenoid version, and the position of the humeral head. The appearance of the glenoid on the affected side was normal in only 11 shoulders. In the remainder it was convex in eight and biconcave in seven cases. The degree of humeral head subluxation was significantly greater (p = 0.001) in affected shoulders than in normal shoulders (152 and 170°, respecively). The presence of abnormal glenoid retroversion and humeral head subluxation increased with age: there was a statistical difference (p = 0.001) between infants younger than 5 months of age and those who were older. Conclusions Magnetic resonance imaging demonstrates shoulder-related anatomical and nerve root lesion, allowing evaluation of neural, osseous, and cartilaginous structures in younger children.


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