Short-term evaluation of humeral stress shielding following reverse shoulder arthroplasty using press-fit fixation compared with cemented fixation

BACKGROUND

The purpose of this study was to compare the functional outcomes and humeral stress shielding of a reverse shoulder arthroplasty (RSA) placed with either cement or press-fit fixation. The hypothesis was that there would be no difference in functional outcomes or stress shielding.

METHODS

We performed a multicenter retrospective review of primary RSAs performed with standard-length stems. The stems were identical in geometry and coating with the only variable being whether the stems were secured with cement or by a press-fit technique. The functional outcomes and radiographs of 93 press-fit stems and 26 cemented stems were reviewed at a minimum of 2 years postoperatively.

RESULTS

Significant improvements were noted in all ranges of motion and functional outcomes from baseline (P < .001), but no difference was found between the groups (P > .05). Calcar osteolysis was seen in 43% of press-fit and 58% of cemented stems (P = .266). Proximal lateral stress shielding was more common in the press-fit group (68%) than in the cemented group (25%) (P = .045). Adaptive changes were considered low in 97% of press-fit stems, and there were no cases of tuberosity resorption. No evidence of loosening or humeral component shift was noted in either group.

CONCLUSION

At short-term follow-up, no differences in functional outcomes or stem loosening were found between press-fit fixation and cemented fixation of an RSA humeral stem. Proximal stress shielding was more common with press-fit fixation with the stem in this study, but the overall changes were considered low in 97% of cases. Further study is needed to evaluate the mid- to long-term differences regarding stress shielding.

Subscapularis Repair During Reverse Total Shoulder Arthroplasty Using a Stem-Based Double-Row Repair: Sonographic and Clinical Outcomes

Background:

Treatment of the subscapularis in reverse total shoulder arthroplasty (RTSA) is a controversial topic, with conflicting evidence regarding outcomes after repair.

Purpose/Hypothesis:

The purpose of this study was to report clinical and sonographic outcomes of a through-implant double-row suture technique for subscapularis repair in RTSA and to compare clinical outcomes and range of motion (ROM) between patients with an intact subscapularis tendon repair versus those whose tendon repair was not intact. The authors hypothesized that the novel repair technique would find more than 80% of tendons intact on ultrasound, with significant improvement in clinical outcome scores and ROM. The authors also hypothesized that patients with an intact subscapularis tendon repair would have better clinical outcomes compared with those with a nonintact tendon repair.

Study Design:

Case series; Level of evidence, 4.

Methods:

The study included all patients who underwent RTSA by 1 of 2 surgeons between August 2016 and March 2017 with the through-implant double-row suture technique for subscapularis repair. Subscapularis tendon integrity was assessed postoperatively via ultrasound at minimum 1-year follow-up. American Shoulder and Elbow Surgeons (ASES), Single Assessment Numeric Evaluation (SANE), and pain visual analog scale (VAS) scores were recorded at the final follow-up visit in addition to ROM measures.

Results:

A total of 48 patients (31 males, 17 females; mean age, 68.9 ± 7.4 years; mean follow-up, 13.8 ± 2.1 months) were included. On ultrasound, the subscapularis was intact in 83.3% of patients. Regarding preoperative versus postoperative outcome scores, the ASES score (mean ± SD) significantly improved from 38.3 ± 14.7 to 81.9 ± 13.6, the SANE score significantly improved from 29.8 ± 24.2 to 75.5 ± 21.0, and the VAS pain score significantly improved from 5.9 ± 2.1 to 1.2 ± 1.6 (P < .001 for all). Forward flexion and external rotation significantly improved. No significant difference existed in clinical outcome scores or ROM between patients with intact versus torn subscapularis tendons based on ultrasound.

Conclusion:

Subscapularis repair using a stem-based double-row repair technique during RTSA demonstrated an overall healing rate of 83.3%, as evidenced by ultrasound examination at short-term follow-up. Integrity of subscapularis repair did not affect clinical outcome or ROM.

Five-year radiographic evaluation of stress shielding with a press-fit standard length humeral stem

Background

Stress shielding of the humeral stem is a known complication in press-fit total shoulder arthroplasty (TSA), but there remain limited data on its prevalence and clinical impact in midterm follow-up. The purpose of this study was to determine the prevalence of humeral stem stress shielding and its impact on functional outcomes at minimum 5-year follow-up in standard length press-fit TSA. The hypothesis was that the presence of stress shielding at minimum 5-year follow-up would not affect functional outcome scores or range of motion (ROM).

Methods

A multicenter retrospective review of primary TSAs performed with a press-fit standard length humeral stem. Functional outcome scores, ROM, and radiographs were reviewed at minimum 5-year follow-up. Prevalence of stress shielding was determined by presence of medial calcar osteolysis and adaptive changes. Function was assessed with the visual analog scale (VAS) pain score, Simple Shoulder Test (SST) score, American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES) score, and Single Assessment Numeric Evaluation (SANE) score, and ROM.

Results

Forty-seven patients with 47 TSAs were available for follow-up at a mean of 79 months postoperation. Overall, 15 of 47 humeral stems had high adaptive change scores (31.9%), and 20 demonstrated medial calcar osteolysis (42.6%). Stems with evidence of stress shielding showed no significant change in SST, VAS, ASES, or SANE scores and minimal change in ROM measurements at minimum 5-year follow-up.

Conclusion

Stress shielding is common at midterm follow-up in press-fit TSA but does not appear to affect functional outcomes.

Adhesive Capsulitis: Demographics and Predictive Factors for Success Following Steroid Injections and Surgical Intervention

Purpose

Examine demographic factors of all patients treated for adhesive capsulitis by a single surgeon, report the treatments and outcomes of these patients, and determine the effectiveness of various treatments, including corticosteroid injections and operative intervention in relation to risk factors for adhesive capsulitis.

Methods

All patients treated for adhesive capsulitis by a single surgeon between 2008 to 2014 with minimum 2 years' follow-up were identified via charts and operative reports and were eligible for inclusion. Demographic information including sex and medical comorbidities was documented. Preintervention and postintervention shoulder range of motion was recorded. Specific treatment information (number of corticosteroid injections, etc) was collected. Treatment outcomes were then compared as an aggregate and among varying comorbidities.

Results

Overall, 1377 patients were treated for adhesive capsulitis (946 women vs 431 men [P = .001]). For patients with adhesive capsulitis: a higher percentage of men than women had diabetes (24.8% vs 17.3% [P = .001]); nondiabetic patients had better forward flexion at initial presentation than patients with diabetes (114° vs 108° [P = .015]); more patients with diabetes required capsular release than nondiabetic patients (13% vs 7.3% [P = .003]); more nondiabetic patients resolved adhesive capsulitis without corticosteroid or surgical intervention than patients with diabetes (83.6% vs 61.7% [P = .001]); more nondiabetic patients resolved adhesive capsulitis after single corticosteroid injection than did patients with diabetes (95.9% vs 86.7% [P = .001]). Multiple intraarticular corticosteroid injections provided no added benefit over a single injection in resolving adhesive capsulitis in patients with diabetes and nondiabetic patients.

Conclusion

In shoulder adhesive capsulitis, women and patients with diabetes are more commonly affected, patients with diabetes respond less favorably to physical therapy in isolation and physical therapy plus corticosteroid injections than nondiabetic patients. No benefit from multiple intraarticular corticosteroid injections was seen compared with a single intraarticular corticosteroid injection in patients with diabetes and nondiabetic patients. Patients with diabetes and nondiabetic patients have functional improvement after capsular release and manipulation if conservative treatment for adhesive capsulitis fails.

Level of Evidence

III, case control.

Can a functional difference be detected in reverse arthroplasty with 135° versus 155° prosthesis for the treatment of rotator cuff arthropathy: a prospective randomized study

BACKGROUND

The purpose of this randomized controlled trial was to compare humeral inclinations of 135° and 155° in patients undergoing primary reverse shoulder arthroplasty (RSA). Our hypothesis was that forward flexion would be higher in the 155° group but be associated with a higher rate of scapular notching.

METHODS

A randomized controlled trial was conducted on 100 primary RSAs performed with a humeral inclination of either 135° or 155°. The prostheses were otherwise identical and a neutral glenosphere was used in all cases. Functional outcome, forward flexion, external rotation, and scapular notching were assessed at a minimum of 2 years postoperatively.

RESULTS

There was no difference in range of motion or functional outcome scores between the 2 groups. In the 155° group, forward flexion improved from 76° to 135° (P < .001) and external rotation remained unchanged (29° vs. 30°; P = .835). In the 135° group, postoperative forward flexion improved from 78° to 132° (P < .001) and external rotation was unchanged (28° vs. 29°; P = .814). Scapular notching was observed in 58% of cases with a 155° inclination compared with 21% with a 135° inclination (P = .009).

CONCLUSION

With a neutral glenosphere there was no difference in postoperative forward flexion or external rotation after an RSA with a humeral inclination of 135° compared with 155°. Scapular notching was reduced with the use of 135° design compared with a 155° design but persists at a rate of 21% at 2-year follow-up in the absence of a lateralized glenosphere.

Stress shielding of the humerus in press-fit anatomic shoulder arthroplasty: review and recommendations for evaluation

Uncemented press-fit humeral stems were developed with the goal of decreasing operative time, preserving bone stock, and easing revision. In recent years, short stems and stemless humeral implants have also become available. These press-fit humeral implants have varying designs that can lead to changes in stress distribution in the proximal humerus. Such stress shielding manifests as bony adaptations and may affect long-term functional outcome and the ability to perform revision. However, current studies of humeral fixation during total shoulder arthroplasty are complicated because a variety of classification systems have been used to report findings. The purpose of this report is to review the current literature on press-fit fixation of the humeral component during total shoulder arthroplasty and propose minimum requirements for radiographic descriptions of stress shielding.

Radiographic changes differ between two different short press-fit humeral stem designs in total shoulder arthroplasty

BACKGROUND

The purpose of this study was to compare the radiographic changes of the humerus in the short term after total shoulder arthroplasty with two different short-stem humeral components. The hypothesis was that there would be no difference in radiographic changes or functional outcome based on component type.

METHODS

A retrospective review was conducted of primary total shoulder arthroplasties performed with a short press-fit humeral component. Group A included a collarless humeral stem with an oval geometry and curved stem (Ascend or Ascend Flex; Wright Medical, Memphis, TN, USA). Group B included a humeral stem with a metaphyseal collar, rectangular geometry, and straight stem (Apex; Arthrex, Inc., Naples, FL, USA). Radiographic changes and functional outcome were evaluated at a minimum of 2 years postoperatively.

RESULTS

There were 42 patients in group A and 35 patients in group B available for analysis. There was no difference in functional outcome between the groups. In group A, the mean total radiographic change score of the humerus was 3.9, with changes classified as low in 38% and high in 62%. In group B, the mean total radiographic change score of the humerus was 2.5, with changes classified as low in 77% and high in 23% (P < .001). Medial calcar osteolysis was present in 71% of group A compared with 28.5% of group B (P < .001).

CONCLUSION

At short-term follow-up, there is no difference in functional outcome or revision between 2 different humeral stem designs. However, bone adaptive changes and the rate of medial calcar osteolysis are significantly different.

Short-term clinical outcome of an anatomic short-stem humeral component in total shoulder arthroplasty

BACKGROUND

Short-stem press-fit humeral components have recently been developed in an effort to preserve bone in total shoulder arthroplasty (TSA), but few studies have reported outcomes of these devices. The purpose of this study was to evaluate the short-term clinical outcomes of an anatomic short-stem humeral component in TSA. We hypothesized that the implant would lead to significant functional improvement with low rates of radiographic loosening.

METHODS

A multicenter retrospective review was performed of TSAs using an anatomic short-stem humeral component (Apex; Arthrex, Inc., Naples, FL, USA). The minimum follow-up was 2 years. Functional outcome was evaluated according to the American Shoulder and Elbow Surgeons score, Visual Analog Scale for pain, Single Assessment Numeric Evaluation, Simple Shoulder Test, and range of motion. A radiographic analysis was performed to evaluate component loosening.

RESULTS

Sixty-four patients with a mean age of 64.1 years were available for follow-up at a mean of 25 months postoperatively. There were significant improvements in the Visual Analog Scale (6 to 2; P < .001), Simple Shoulder Test (4 to 10; P < .001), Single Assessment Numeric Evaluation (32 to 84; P < .001), and American Shoulder and Elbow Surgeons (37 to 80; P < .001) scores. Forward flexion improved from 116° to 148° (P < .001), external rotation improved from 30° to 57° (P < .001), and internal rotation improved from an average spinal level of S1 to L2 (P < .001). On radiographic examination, 9% of stems were deemed at risk for loosening, but there was no gross loosening in any patient.

CONCLUSIONS

TSA with an anatomic press-fit short-stem humeral component is associated with significant improvements in clinical outcomes, without evidence of component loosening at short-term follow-up.

Healing and functional outcome of a subscapularis peel repair with a stem-based repair after total shoulder arthroplasty

BACKGROUND

The purpose of this study was to evaluate functional outcome and healing of a subscapularis peel with a stem-based repair after total shoulder arthroplasty (TSA). The hypothesis was that the repair would lead to subscapularis healing in the majority of cases.

METHODS

A prospective analysis was performed on a consecutive series of TSAs. Range of motion and functional outcome were assessed according to American Shoulder and Elbow Surgeons, Single Assessment Numeric Evaluation, Simple Shoulder Test, and visual analog scale scores at a minimum follow-up of 1 year. Belly-press and lift-off tests were also performed. An ultrasound evaluation assessed subscapularis healing at final follow-up.

RESULTS

At a mean follow-up of 15 months, 60 patients (mean age, 64 years) were examined. Mean forward flexion improved from 115° to 137°. External rotation at the side improved from 27° to 52°, and internal rotation improved from L4 to L2 (P < .05). American Shoulder and Elbow Surgeons score improved from 34.3 to 79.8 (P < .001). Likewise, the Single Assessment Numeric Evaluation and Simple Shoulder Test scores showed significant improvement from 33.1 to 85.3 and 4.3 to 10.2, respectively (P < .001). The visual analog scale score for pain decreased from 5.8 to 0.7 (P < .001). On ultrasound examination, the subscapularis was healed intact in 55 cases (91.7%), attenuated in 3 cases (5%), and torn in 2 cases (3.3%).

CONCLUSION

A stem-based repair of a subscapularis peel after TSA leads to functional improvement in the majority of cases with >90% postoperative healing of the subscapularis.

Biomechanical Study of a Subscapularis Repair Technique for Total Shoulder Arthroplasty

Secure subscapularis repair is an essential element of total shoulder arthroplasty. Some surgeons prefer subscapularis peel because of ease of use, but some evidence suggests that lesser tuberosity osteotomy provides better fixation. The authors developed a novel, through-implant repair technique and performed a biomechanical study of its strength with cadaveric specimens. The authors obtained 20 matched pairs of cadaveric shoulders and inserted an uncemented short-stemmed humeral prosthesis that facilitates through-implant repair in all specimens. For each cadaver, the subscapularis was repaired with lesser tuberosity osteotomy and standard suture technique on 1 side, and the contralateral subscapularis was repaired with a novel through-implant suture repair and subscapularis peel technique. Displacement of the subscapularis footprint, ultimate load to failure, and stiffness of each repair were measured and compared between fixation groups. Mean±SD displacement of the lesser tuberosity osteotomy group was 0.75±0.94 mm at 10 cycles and 2.24±2.76 mm at 500 cycles. Mean±SD load to failure was 612±185 N, and mean±SD ultimate stiffness was 119±32 N/mm. No significant differences were noted between the lesser tuberosity osteotomy group and the subscapularis peel group in mean±SD displacement at 10 cycles (1.09±1.30 mm, P=.31), mean±SD displacement at 500 cycles (2.85±2.43 mm, P=.26), mean±SD load to failure (683±274 N, P=.31), or mean±SD ultimate stiffness (117±37 N/mm, P=.88). In a biomechanical testing model, through-implant subscapularis repair provided secure fixation relative to currently accepted subscapularis repair techniques in total shoulder replacement. [Orthopedics. 2016; 39(5):e937-e943.].

Early Outcomes Following Metal-on-Metal Reverse Total Shoulder Arthroplasty in Patients Younger Than 50 Years

Reverse total shoulder arthroplasty (TSA) is a useful intervention for older patients with glenohumeral arthritis and a deficient rotator cuff. However, as a semiconstrained prosthesis, conventional reverse TSA implanted in a young patient could fail over time secondary to polyethylene wear and subsequent osteolysis. A metal-on-metal prosthesis may avoid this type of failure. The purpose of this study is to assess the outcomes in an initial cohort of young patients who underwent reverse TSA using a metal-on-metal prosthesis. Surgical indications included age younger than 50 years with a functioning deltoid and significant impairment of shoulder function with irreparable rotator cuff due to tumor resection, arthritis, or revision surgery. Nine patients with an average age of 37 years underwent implantation of a custom metal-on-metal reverse TSA prosthesis. All patients had a minimum 12-month follow-up or a failure of their procedure requiring revision surgery prior to 1 year. American Shoulder and Elbow Surgeons (ASES) scores, Constant scores, and range of motion were recorded and analyzed pre- and postoperatively to assess improvement, and all complications were noted. Average ASES score improved from 47 points preoperatively to 73.4 points postoperatively (P=.013). Average Constant and adjusted Constant scores improved from 20.8 points and 16% preoperatively to 61.8 points and 67.3% postoperatively, respectively (P=.019 and P=.068). Mean postoperative active forward flexion and active external rotation were 119.4° and 10°, respectively. Complications included the following: 3 patients sustained a postoperative dislocation, 1 patient had a glenoid fracture and complete loss of fixation of the baseplate, and 1 patient experienced dissociation of the glenosphere from the base-plate. Although metal-on-metal reverse TSA may appear to be an attractive choice in the treatment of young patients with limited reconstructive options, postoperative outcomes are disappointing, and the complication rate is high. [Orthopedics.2016; 39(5):e957-e961.].

Cost Analysis of Hemiarthroplasty Versus Reverse Shoulder Arthroplasty for Fractures

Complex proximal humerus fractures in older patients can be treated with hemiarthroplasty (HA) or reverse shoulder arthroplasty (RSA), with both providing good pain relief and function. This study compared the costs, complications, and outcomes of HA vs RSA after proximal humerus fracture in older patients. Patients 65 years or older who were admitted between January 2007 and August 2011 with a 3- or 4-part proximal humerus fracture and treated with HA or RSA were identified. Surgeries were performed at the same institution by 1 of 3 surgeons trained in trauma or shoulder surgery. Operating room costs, implant costs, total costs to the patient and hospital, and range of motion were compared. In the study group, 8 patients (7 women and 1 man; mean age, 77 years) received HA and 16 patients (13 women and 3 men; mean age, 77 years) received RSA. Hemiarthroplasty implant cost and operating room cost were $9140 and $8900 less than those of RSA, respectively (P<.001). The total cost to the patient was $33,480 for HA vs $57,000 for RSA (P<.001) with no difference in admission length, transfusion requirements, or final range of motion. In patients with complex proximal humerus fractures, RSA restored function similar to HA and resulted in better pain and outcome scores. However, RSA had a significantly higher cost to both the patient and the hospital compared with HA. Further investigation of postsurgical rehabilitation costs, skilled nursing needs, or revision surgery will elucidate whether there is long-term functional or financial benefits to RSA over HA. [Orthopedics. 2016; 39(4):230-234.].

Stem-Based Repair of the Subscapularis in Total Shoulder Arthroplasty

Management of the subscapularis is an important component of total shoulder arthroplasty. This technique article describes a stem-specific approach to repairing the subscapularis.

Hyper extension-internal rotation (HERI): A new test for anterior gleno-humeral instability

BACKGROUND

Anterior shoulder dislocation causes injury to the inferior gleno-humeral ligament (IGHL) and capsule. Clinical manoeuvres currently used to evaluate the IGHL test for, and may induce, apprehension. We developed the hyper extension-internal rotation (HERI) test to assess the IGHL and inferior capsule without causing apprehension or inducing a risk of gleno-humeral dislocation.

HYPOTHESIS

The HERI test is easy to perform and reproducible, induces no risk of gleno-humeral dislocation during the manoeuvre, and causes no apprehension in the patients.

MATERIAL AND METHODS

We studied 14 fresh cadaver shoulders. Each specimen was positioned supine with the lateral edge of the scapula on the table and the upper limb hanging down beside the table under the effect of gravity. This position produced hyperextension and internal rotation of the gleno-humeral joint. For each shoulder, the range of extension (°) was measured before and after isolated IGHL section. Then, we performed the HEIR test in 50 patients with chronic unilateral anterior gleno-humeral instability and we compared the range of extension between the normal and abnormal sides.

RESULTS

In the cadaver study, isolated IGHL section increased the angle of extension by a mean of 14.5° (11°-18°) compared to the pre-injury values. In the clinical study, the mean difference in extension angles between the normal and abnormal sides was 14.5°. The patients reported no apprehension during the HERI test.

CONCLUSION

The angle of extension increases after section or injury of the IGHL in cadaver specimens and patients, respectively. When the inferior capsule and IGHL are damaged, the angle of extension increases compared to the normal side. Lesions to these structures can be evaluated clinically by performing the HERI test.

LEVEL OF EVIDENCE

III.

Medialized Versus Lateralized Center of Rotation in Reverse Shoulder Arthroplasty

Reverse shoulder arthroplasty may be performed using components that medialize or lateralize the center of rotation. The purpose of this prospective study was to directly compare 2 reverse shoulder arthroplasty designs. Two treatment groups and 1 control group were identified. Group I comprised 9 patients using a medialized Grammont-style (GRM) prosthesis with a neck-shaft angle of 155°. Group II comprised 9 patients using a lateralized (LAT) prosthesis with a neck-shaft angle of 135°. Pre- and postoperative assessment of range of motion, American Shoulder and Elbow Surgeons score, and visual analog scale pain score were performed. Radiographic measurements of lateral humeral offset and acromiohumeral distance were compared. The GRM prosthesis achieved greater forward flexion (143.9° vs 115.6°; P=.05), whereas the LAT achieved greater external rotation (35.0° vs 28.3°; P=.07). The lateral humeral offset was greater for the LAT prosthesis compared with the GRM prosthesis, but this distance was not significantly different from that found in the control group. The acromiohumeral distance was significantly greater in the GRM prosthesis group compared with both the LAT and the control groups. The results of this study confirm that different reverse shoulder arthroplasty designs produce radiographically different anatomy. Whereas the GRM prosthesis significantly alters the anatomy of the shoulder, the LAT design can preserve some anatomic relationships found in the normal shoulder. The clinical outcomes indicate that this may have an effect on range of motion, with traditional designs achieving greater forward flexion and lateralized designs achieving greater external rotation.

Neer Award 2015: A randomized, prospective evaluation on the effectiveness of tranexamic acid in reducing blood loss after total shoulder arthroplasty

BACKGROUND

Tranexamic acid (TXA) is an antifibrinolytic agent that has been shown to significantly reduce blood loss and transfusion requirements after total knee and hip arthroplasty. The purpose of this study was to evaluate the effect of TXA on postoperative blood loss after shoulder arthroplasty.

METHODS

A total of 111 patients (62 women; average age, 67 years) who underwent shoulder arthroplasty were prospectively randomized in double-blinded fashion to receive either 100 mL of normal saline or 100 mL of normal saline with 2 g TXA by topical application into the wound at the completion of the case. All patients received a postoperative drain. Drain output representing postoperative blood loss, transfusion requirements, and change in hemoglobin level were recorded. All postoperative complications were noted.

RESULTS

The average blood loss recorded after surgery was 170 mL in the placebo group and 108 mL in the TXA group (P = .017). The average change in hemoglobin level was 2.6 g/dL in the placebo group and 1.7 g/dL in the TXA group (P < .001). There were no transfusion requirements or postoperative complications noted in either group.

DISCUSSION

In this cohort of patients, those treated with TXA experienced a significantly lower amount of postoperative blood loss and a significantly smaller change in hemoglobin level compared with those treated with placebo. Further work is required to determine the effectiveness and clinical significance of TXA in reducing transfusion requirements in shoulder arthroplasty and, more specifically, shoulder arthroplasty performed for complicated patients or for trauma and fracture patients.

Radiostereometric and Radiographic Analysis of Glenoid Component Motion After Total Shoulder Arthroplasty

Aseptic glenoid component loosening is a common cause of total shoulder arthroplasty (TSA) failure, but early detection is difficult because pain often appears late and radiolucent lines are of uncertain significance. This study sought to answer the following questions: (1) What types of glenoid component motion may be observed during the first 3 years following implantation?; (2) Is the appearance of radiolucent lines around the glenoid component a reliable indicator of component motion?; and (3) Are clinical outcomes correlated with early glenoid component motion within the first 3 years after TSA? Eleven patients (mean age, 60.6 years) underwent TSA using a cemented, all-polyethylene glenoid component with tantalum bead implantation. Clinical outcomes (American Shoulder and Elbow Surgeons [ASES] score, visual analog scale [VAS] pain score, and range of motion) were compared pre- and postoperatively, and radiolucencies were graded according to the criteria of Lazarus et al. Patients were evaluated using radiostereometric analysis at 6 months and 1, 2, and 3 years postoperatively to measure component micromotion in translation and rotation. At a mean follow-up of 50.2 months, mean ASES score had improved from 30.3 to 81.3 (P<.001), mean VAS pain score had improved from 8 to 1 (P<.001), active forward flexion had improved from 109° to 155° (P=.001), active external rotation had improved from 28° to 54° (P=.003), and internal rotation had improved from the level of the sacrum to L3 (P=.002). Radiolucencies were detected around none of the components at 1 year, 6 components at 2 years, and 5 components at 3 years, and these radiolucencies were mostly found around components that experienced high levels of rotational motion.

Scapular neck length and implications for reverse total shoulder arthroplasty: An anatomic study of 442 cadaveric specimens

Purpose:

Reverse total shoulder arthroplasty (RTSA) may be used to treat a variety of pathologic shoulder conditions, but complications such as scapular notching continue raise concerns. Variable anatomy surrounding the glenoid may have implications for future RTSA design, but at present the anatomy of the scapular neck in the human population has not been clearly defined.

Materials and Methods:

442 human scapulae from the Hamann-Todd Osteological Collection were measured for scapular neck length (SNL) and scapular neck angle (SNA). SNL was defined as the distance from the most lateral portion of the infraglenoid tubercle to the most inferolateral portion of the glenoid fossa. The SNA was measured according to Gerber et al. previously. The mean, standard deviation and ranges for SNL and SNA were calculated and compared based on sex and race, and interobserver variability was calculated.

Results:

The mean SNL was 1.06 cm ± 0.33 cm (0.37-2.43 cm). Males demonstrated a larger SNL (1.08 cm ± 0.33 cm) than females (1.01 cm ± 0.32 cm) (P < 0.12), and Caucasians (1.09 cm ± 0.33 cm) demonstrated a significantly larger SNL than African-Americans (1.00 cm ± 0.32) (P < 0.01). The mean SNA was 106.7° ± 11.0° (76.9-139.4°). No significant correlation was found between SNL and SNA (Pearson Correlation Coefficient = 0.018) (P < 0.702).

Conclusion:

Scapular neck length and SNA vary widely within the population but there appears to be a tendency towards increased SNL in males and Caucasians.

Clinical Relevance:

The anatomy of the scapular neck may have significant implications for RTSA design, surgical planning, and reduction of associated complications.

Tendinopathy of the long head of the biceps tendon: histopathologic analysis of the extra-articular biceps tendon and tenosynovium

BACKGROUND

Bicipital tendinitis is a common cause of anterior shoulder pain, but there is no evidence that acute inflammation of the extra-articular long head of the biceps (LHB) tendon is the root cause of this condition. We evaluated the histologic findings of the extra-articular portion of the LHB tendon and synovial sheath in order to compare those findings to known histologic changes seen in other tendinopathies.

METHODS

Twenty-six consecutive patients (mean age 45.4±13.7 years) underwent an open subpectoral biceps tenodesis for anterior shoulder pain localized to the bicipital groove. Excised tendons were sent for histologic analysis. Specimens were graded using a semiquantitative scoring system to evaluate tenocyte morphology, the presence of ground substance, collagen bundle characteristics, and vascular changes.

RESULTS

Chronic inflammation was noted in only two of 26 specimens, and no specimen demonstrated acute inflammation. Tenocyte enlargement and proliferation, characterized by increased roundness and size of the cell and nucleus with proteoglycan matrix expansion and myxoid degenerative changes, was found in all 26 specimens. Abundant ground substance, collagen bundle changes, and increased vascularization were visualized in all samples.

CONCLUSION

Anterior shoulder pain attributed to the biceps tendon does not appear to be due to an inflammatory process in most cases. The histologic findings of the extra-articular portion of the LHB tendon and synovial sheath are similar to the pathologic findings in de Quervain tenosynovitis at the wrist, and may be due to a chronic degenerative process similar to this and other tendinopathies of the body.

Acromial stress fractures: correlation with acromioclavicular osteoarthritis and acromiohumeral distance

Fractures around the acromion are a known complication of reverse total shoulder arthroplasty. The literature provides limited data on the risk factors associated with this complication as well as the ultimate outcomes after nonoperative treatment. The goal of this study was to report clinical outcomes in patients with acromial fractures after nonoperatively treated reverse total shoulder arthroplasty. The authors performed a retrospective review of 125 patients undergoing reverse total shoulder arthroplasty that included several acromial stress fractures in the postoperative period. They prospectively compared radiographic data, including acromiohumeral distance, the presence of acromioclavicular joint arthritis, clinical measures of motion, visual analog scale (VAS) pain score, American Shoulder and Elbow Surgeons (ASES) score, and Single Assessment Numeric Evaluation (SANE) score, in 2 groups based on the presence or absence of fracture in the postoperative period. Fourteen patients (11.2%) had an acromial fracture after reverse total shoulder arthroplasty at an average of 5.1 months postoperatively. Patients who had fractures had worse postoperative forward elevation before fracture (116.6 vs 143.5; P=.02) and greater pain relief after reverse shoulder replacement, before fracture (P=.04). No significant difference was found between groups when the degree of arm lengthening was compared (27.6 vs 26.2 mm), and no difference was found in the prevalence of degenerative acromioclavicular joint changes identified preoperatively (66.4% vs 77.3%). After conservative management, most patients who had an acromial fracture returned to a functional level that was comparable to that achieved before fracture.

Biologic resurfacing of the glenoid with humeral head resurfacing for glenohumeral arthritis in the young patient

BACKGROUND

Resurfacing of the glenoid with an interposition soft tissue graft in conjunction with humeral head arthroplasty has been proposed as an option to improve glenohumeral arthritis in young patients while avoiding the potential complications associated with total shoulder arthroplasty. There currently exist minimal outcomes data for this procedure, and the results have not been consistent. The purpose of this study was to report on the outcomes in our cohort of patients aged younger than 55 years.

METHODS

A multicenter review of 16 patients who had undergone humeral head arthroplasty with soft tissue interposition grafting of the glenoid was performed. All patients had a minimum follow-up time of 24 months, unless revision surgery was required because of failure of the procedure.

RESULTS

At a mean follow-up of 60 months, the patients showed improvement in the visual analog scale score for pain from 8.1 to 5.8 (P < .05), and the American Shoulder and Elbow Surgeons score improved from 23.2 to 57.7 (P < .05). Forward elevation improved from 128° to 134° (P = .33), and external rotation improved from 28° to 32° (P = .5). Internal rotation showed no improvement. Conversion to a total shoulder arthroplasty was performed in 7 patients (44%) at a mean of 36 months.

CONCLUSIONS

The optimal management for the young patient with arthritis has not yet been established. Because of the limited improvement in patient outcomes and the relatively high revision rate, biologic resurfacing of the glenoid with humeral head resurfacing is no longer our primary treatment option for young patients and should be used with caution.

Diagnostic accuracy in detecting tears in the proximal biceps tendon using standard nonenhancing shoulder MRI

BACKGROUND

There is a paucity of data in the literature evaluating the performance of noncontrast MRI in the diagnosis of partial and complete tears of the proximal portion of the long head of the biceps (LHB) tendon. The objective of this study was to evaluate the accuracy of noncontrast magnetic resonance imaging (MRI) compared to arthroscopy for the diagnosis of pathology involving the intra-articular portion of the LHB tendon.

METHODS

We conducted a retrospective review of 66 patients (mean age 57.8 years, range 43-70 years) who underwent shoulder arthroscopy and evaluation of the LHB tendon after having had a noncontrast MRI of the shoulder. Biceps pathology was classified by both MRI and direct arthroscopic visualization as either normal, partial tearing, or complete rupture, and arthroscopy was considered to be the gold standard. We then determined the sensitivity, specificity, and positive- and negative-predictive values of MRI for the detection of partial and complete LHB tears.

RESULTS

MRI identified 29/66 (43.9%) of patients as having a pathologic lesion of the LHB tendon (19 partial and ten complete tears) while diagnostic arthroscopy identified tears in 59/66 patients (89.4%; 50 partial and 16 complete). The sensitivity and specificity of MRI for detecting partial tearing of the LHB were 27.7% and 84.2%, respectively (positive predictive value =81.2%, negative predictive value =32.0%). The sensitivity and specificity of MRI for complete tears of the LHB were 56.3% and 98.0%, respectively (positive predictive value =90.0%, negative predictive value =87.5%).

CONCLUSION

Standard noncontrast MRI of the shoulder is limited in detecting partial tears and complete ruptures of the intra-articular LHB tendon. Surgeons may encounter pathologic lesions of the LHB tendon during arthroscopy that are not visualized on preoperative MRI.