Glenoid component loosening remains a common mode of failure for total shoulder arthroplasty and has inspired improvements in implant design, instrumentation, and surgical technique. The purpose of this manuscript was to evaluate the incidence of radiolucent lines and glenoid seating on initial postoperative radiographs using a modern pegged-glenoid design, instrumentation, and surgical technique.
Materials and Methods:
We performed a retrospective analysis of a consecutive series of 100 pegged-glenoid total shoulder replacements. In cases of excessive glenoid version, the glenoid was asymmetrically reamed to recreate more normal version. Initial postoperative radiographs were evaluated for the presence of radiolucent lines and completeness of glenoid seating. The preoperative glenoid version measured on axial computed tomography (CT) scans was used to compare differences in version among those with complete and incompletely seated glenoids.
The rate of radiolucent lines observed on postoperative radiographs was 0%. Complete glenoid seating (Grade A) was observed in 81 patients (observer 1) and 82 patients (observer 2). Measurements of preoperative CT scans found a higher percentage of abnormal glenoid version for incompletely seated glenoids (47%) than completely seated glenoids (34%) but no significant difference (P = 0.327). The mean preoperative glenoid retroversion for incompletely seated glenoids was 12.1° and 9.1° for completely seated glenoids (P = 0.263).
Modern surgical techniques, surgical instrumentation, and peg glenoid design have facilitated the ability to eliminate radiolucent lines on initial postoperative radiographs with high rates of complete seating of glenoid components. Incomplete seating may be related to incomplete correction of glenoid version.
Glenoid component; pegged-glenoid; radiolucent lines; total shoulder arthroplasty
Glenoid component malposition is associated with poor function and early failure of both anatomic and reverse total shoulder arthroplasty. Glenoid positioning is challenging particularly in the setting of bone loss or deformity. Recently, the use of computer assistance has been shown to reduce implantation error. The aim of this study is to evaluate the accuracy of patient-specific instrumentation in cases of anatomic and reverse shoulder replacement in vivo.
Twenty patients underwent total shoulder arthroplasty using a computed tomography (CT)-based patient-specific instrumentation (PSI) system, ten anatomic and ten reverse. Preoperative three-dimensional digital templating of glenoid component position was undertaken and surgery then performed using a custom-made guide. Postoperative CT scans were used to compare final implanted component position to the preoperatively planned position in the same patient.
Final component position and orientation closely reflected the preoperatively templated position. Mean deviation in the glenoid version from planned was 1.8° ±1.9° (range, 0.1°–7.3°). Mean deviation in inclination was 1.3° ±1.0° (range, 0.2°–4.5°). Mean deviation in position on the glenoid face was 0.5 ± 0.3 mm (range, 0.0–1.3 mm) in the anteroposterior plane and 0.8 ± 0.5 mm (range, 0.0–1.9 mm) in the superoinferior plane. Actual achieved version was within 7° of neutral in all cases except for one where it was deliberately planned to be outside of this range.
PSI in both anatomic and reverse shoulder arthroplasty is highly accurate in guiding glenoid component implantation in vivo. The system can reliably correct bony deformity.
Custom guide; digital templating; glenoid malposition; patient-specific; shoulder arthroplasty; three-dimensional planning
There are multiple reported risk factors and a wide range of reported blood transfusion rates for total shoulder arthroplasty (TSA). There are no evidence-based guidelines for blood transfusions in TSA patients.
Materials and Methods:
We utilized the Nationwide Inpatient Sample to analyze 51,191 patients undergoing TSA between 1998 and 2011. The purpose was to describe the incidence and identify the preoperative factors that are independently associated with blood transfusion after TSA. In addition, we studied the association of blood transfusions with certain variables such as length of stay (LOS), total charges, and payer status.
The blood transfusion rate in our study was 6.1%. There was no difference in the rate of blood transfusions over the study period (P < 0.001). In our logistic regression model, significant associations were found with increased age (odds ratio [OR] =1.03), white race (OR = 1.05), higher Charlson-Deyo score (OR = 1.12), presence of ischemic heart disease (OR = 1.24), blood loss anemia (OR = 1.65), female gender (OR = 1.94), presence of coagulation disorders (OR = 2.25), and presence of deficiency anemia (OR = 3.5). Patients receiving a blood transfusion had higher total charges, a longer hospital LOS, and were more likely to be Medicare payers (P < 0.001).
Our study found five clinically significant risk factors for blood transfusions for TSA: female gender, ischemic heart disease, deficiency anemia, coagulation disorder, and blood loss anemia. Patients with these risk factors should be considered higher risk for requiring a blood transfusion after TSA and counseled appropriately.
Level of Evidence:
Level II, retrospective cohort study, prognostic study.
Allogeneic blood transfusion; autologous blood transfusion; complications; total shoulder arthroplasty
Rotator cuff tears have been reported to be uncommon following total shoulder arthroplasty (TSA). Postoperative rotator cuff tears can lead to pain, proximal humeral migration, and glenoid component loosening. The purpose of this paper was to evaluate the incidence of post-TSA rotator cuff tears or dysfunction in osteoarthritic patients. A systematic review of multiple databases was performed using preferred reporting items for systematic reviews and meta-analyses guidelines. Levels I-IV evidence clinical studies of patients with primary osteoarthritis with a minimum 2-year follow-up were included. Fifteen studies with 1259 patients (1338 shoulders) were selected. Student's t-tests were used with a significant alpha value of 0.05. All patients demonstrated significant improvements in motion and validated clinical outcome scores (P < 0.001). Radiographic humeral head migration was the most commonly reported data point for extrapolation of rotator cuff integrity. After 6.6 ± 3.1 years, 29.9 ± 20.7% of shoulders demonstrated superior humeral head migration and 17.9 ± 14.3% migrated a distance more than 25% of the head. This was associated with an 11.3 ± 7.9% incidence of postoperative superior cuff tears. The incidence of radiographic anterior humeral head migration was 11.9 ± 15.9%, corresponding to a 3.0 ± 13.6% rate of subscapularis tears. We found an overall 1.2 ± 4.5% rate of reoperation for cuff injury. Nearly all studies reported indirect markers of rotator cuff dysfunction, such as radiographic humeral head migration and clinical exam findings. This systematic review suggests that rotator cuff dysfunction following TSA may be more common than previously reported. IV, systematic review of Levels I-IV studies.
Glenohumeral; humeral head migration; osteoarthritis; rotator cuff; rupture; total shoulder arthroplasty
Primary bone tumors around the elbow represent <1% of all the skeletal tumors. Surgery with or without adjuvant therapy (radiotherapy, chemotherapy) is the treatment of choice for malignant tumors. Reconstruction of the elbow and forearm in malignant tumors is challenging as it involves a complex interplay between multiple joints which need to be stabilized for the optimal functional outcome. We describe a new technique for the reconstruction of the elbow after resection of a proximal ulna tumor with articular radio-ulnar synostosis with the creation of a single bone forearm. We attempted to achieve a mobile elbow and stable wrist joint with the radio-ulnar union at the proximal articular surface of the ulna resulting in a single bone forearm. The procedure involves an oblique osteotomy preserving the olecranon process (after taking adequate margins based on oncological principles) and its articular cartilage along with the attachment of the triceps tendon. Then the radial head was partially denuded of its cartilage using a burr, leaving cartilage only on the volar side, and then fused to the remnant olecranon. Osteosynthesis was done using compression screw and tension band wiring. The advantages of this procedure are that the mobility at wrist and elbow are retained, it requires minimal hardware and allows for primary closure of the wound.
Biological reconstruction; elbow joint; Ewing sarcoma; osteosynthesis; single bone forearm; synostosis
The case of a 29-year-old man who had osteochondritis dissecans on the medial aspect of the humeral head is reported. Repetitive micro-trauma at a low elevated arm position was thought to have induced the osteochondral lesion.
Humeral head; osteochondral lesion; osteochondritis dissecans
As the incidence of reverse shoulder arthroplasty (RSA) increases, so will the revision burden. At times, the revision surgeon may be faced with a well-fixed component on one side of the joint and revision implants from a different manufacturer. The ability to use glenoid and humeral implants from different manufacturers could simplify the revision procedure. This study hypothesized that across a range of RSA systems, some implants would demonstrate high size compatibility and others would demonstrate low compatibility.
Materials and Methods:
Six polyethylene inserts each from eight reverse total shoulder arthroplasty systems were examined (48 total inserts). All inserts were scanned using a laboratory micro-computed tomography scanner at 50 μm isotropic voxel spacing, and their surface geometries were reconstructed. The different implant geometries were co-registered, and the three-dimensional (3D) variability between the articular surfaces of the different implant systems was measured. Intrasystem manufacturing variability was also determined by measuring the 3D variability of inserts from the same system.
The intersystem polyethylene articular surface deviations between same-size systems were not significantly different (P = 0.61) and were a mean maximum of 60 ± 16 μm (range: 30-80 μm). Intrasystem manufacturing variability was equivalent between all but two models, averaging 49 ± 17 μm (range: 23-99 μm).
Differences in articular geometry between same-size inserts from different systems were on the same scale as intrasystem manufacturing variability, suggesting that different implant systems of the same nominal diameter could potentially be used interchangeably in revision or extenuating circumstances.
The results of this study suggest that surgeons can theoretically interchange same-sized implant components from the different RSA systems tested when conducting revisions.
Polyethylene; micro-computed tomography; reverse shoulder arthroplasty; revision; shoulder arthroplasty
The Nice knot is a bulky double-stranded knot. Biomechanical data supporting its use as well as the number of half hitches required to ensure knot security is lacking.
Materials and Methods:
Nice knots with, one, two, or three half-hitches were compared with the surgeon's and Tennessee slider knots with three half hitches. Each knot was tied 10 times around a fixed diameter using four different sutures: FiberWire (Arthrex, Naples, FL), Ultrabraid (Smith and Nephew, Andover, MA), Hi-Fi (ConMed Linvatec, Largo, FL) and Force Fiber (Teleflex Medical OEM, Gurnee, IL). Cyclic testing was performed for 10 min between 10N and 45N, resulting in approximately 1000 cycles. Displacement from an initial 10N load was recorded. Knots surviving cyclic testing were subjected to a load to failure test at a rate of 60 mm/min. Load at clinical failure: 3 mm slippage or opening of the suture loop was recorded. Bulk, mode of ultimate failure, opening of the loop past clinical failure, was also recorded.
During cyclic testing, the Nice knots with one or more half-hitches performed the best, slipping significantly less than the surgeon's and Tennessee Slider (P < 0.002). After one half-hitch, the addition of half-hitches did not significantly improve Nice knot performance during cyclic testing (P > 0.06). The addition of half-hitches improved the strength of the Nice knot during the force to failure test, however after two half-hitches, increase of strength was not significant (P = 0.59). While FiberWire was the most bulky of the sutures tested, it also performed the best, slipping the least.
The Nice knot, especially using FiberWire, is biomechanically superior to the surgeon's and Tennessee slider knots. Two half hitches are recommended to ensure adequate knot security.
Biomechanics; cyclic loading; half-hitches; knot security; load to failure; Nice knot
The purpose of this study is to assess the outcomes of a consecutive series of patients who underwent revision surgery after humeral head resurfacing (HHR). Our joint registry was queried for all patients who underwent revision arthroplasty for failed HHR at our institution from 2005 to 2010. Eleven consecutive patients (average age 54 years; range 38-69 years) that underwent revision of 11 resurfacing arthroplasties were identified. The primary indication for resurfacing had been osteoarthritis in six, glenoid dysplasia in two, a chondral lesion in two, and postinstability arthropathy in one patient. The indication for revision was pain in 10 and infection in one patient. Seven patients had undergone an average of 1.9 surgeries prior to resurfacing (range 1-3).
Materials and Methods:
All patients were revised to stemmed arthroplasties, including one hemiarthroplasty, two reverse, and eight anatomic total shoulder arthroplasties at a mean 33 months after primary resurfacing (range 10-131 months). A deltopectoral approach was used in seven patients; four patients required an anteromedial approach due to severe scarring. Subscapularis attenuation was found in four cases, two of which required reverse total shoulder arthroplasty. Bone grafting was required in one glenoid and three humeri.
At a mean follow-up of 3.5 years (range 1.6-6.9 years), modified Neer score was rated as satisfactory in five patients and unsatisfactory in six. Abduction and external rotation improved from 73° to 88° (P = 0.32) and from 23° to 32° (P = 0.28) respectively. Reoperation was required in two patients, including one hematoma and one revision for instability.
Outcomes of revision of HHR arthroplasty in this cohort did not improve upon those reported for revision of stemmed humeral implants. A comparative study would be required to allow for definitive conclusions to be made.
Humeral head resurfacing; revision; shoulder arthroplasty
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.
Biological resurfacing; chondrolysis; glenoid dysplasia; hemiarthroplasty; inflammatory arthritis; osteonecrosis; shoulder arthroplasty; young
Arthroscopic transosseous (TO) rotator cuff repair has recently emerged as a new option for surgical treatment of symptomatic rotator cuff tears. Limited data is available regarding outcomes using this technique. This study evaluated midterm clinical outcomes following a novel arthroscopic TO (anchorless) rotator cuff repair technique.
Materials and Methods:
A consecutive series of 107 patients and 109 shoulders underwent arthroscopic TO (anchorless) rotator cuff repair for a symptomatic full-thickness tear. Pre and postoperative range of motion (ROM) was compared at an average of 11.8 months. Postoperative outcome scores were obtained at an average of 38.0 months. Statistical analysis was performed to compare pre and postoperative ROM data. Univariate analysis was performed using Student's t-test to compare the effect of other clinical characteristics on final outcome.
Statistically significant improvements were noted in forward flexion, external rotation and internal rotation (P < 0.0001). Average postoperative subjective shoulder value was 93.7, simple shoulder test 11.6, and American Shoulder and Elbow Surgeons (ASES) score 94.6. According to ASES scores, results for the 109 shoulders available for final follow-up were excellent in 95 (87.1%), good in 8 (7.3%), fair in 3 (2.8%), and poor in 3 (2.8%). There was no difference in ROM or outcome scores in patients who underwent a concomitant biceps procedure (tenodesis or tenotomy) compared with those who did not. Furthermore, there was no significant difference in outcome between patients who underwent either biceps tenodesis or tenotomy. Age, history of injury preceding the onset of pain, tear size, number of TO tunnels required to perform the repair, and presence of fatty infiltration did not correlate with postoperative ROM or subjective outcome measures at final follow-up. Two complications and four failures were noted.
Arthroscopic TO rotator cuff repair technique leads to statistically significant midterm improvement in ROM and satisfactory midterm subjective outcome scores with low complication/failure rates in patients with average medium-sized rotator cuff tears with minimal fatty infiltration. Further work is required to evaluate radiographic healing rates with this technique and to compare outcomes following suture anchor repair.
Level of Evidence:
Arthroscopic transosseous rotator cuff repair; rotator cuff tear; shoulder arthroscopy; suture anchors
This reports presents the case of a combined clavicle fracture malunion and chronic Type IV acromioclavicular (AC) joint dislocation. The patient was seen acutely in the emergency department following a mountain bike accident at which time the clavicle fracture was identified and managed conservatively however the AC dislocation was not diagnosed. The patient presented 25 months following the injury with persistent pain and disability and was treated with clavicle osteotomy and AC stabilization. We document the clinical details, surgical treatment and outcome.
Acromioclavicular joint dislocations; athletic injuries; osteotomy; shoulder fractures malunited
Pinning with metallic wires is a suitable therapeutic option for proximal humeral fractures. Loosening and migration of such devices from this site is uncommon. Despite infrequently occurring, however, the literature reports dramatic and potentially lethal complications related to wires dislocation. A 69-year-old woman underwent closed reduction and fixation of a proximal 3-part humeral fracture by mean of two retrograde Kirschner wires and one anterograde threaded pin. One month after surgery, during a routine follow-up control, it was diagnosed the migration of the threaded pin in the left lung parenchyma. In the meantime, the only symptom the patient complained was an episodic intercostal pain of mild intensity, with referred onset 1 week after surgery. The migrated pin was removed through thoracoscopic approach in the emergency setting, without intra- or post-operative complications. Only a few authors reported similar complications after fixation of proximal humeral fractures. Immediate surgical removal of the device is always mandatory. When considering pinning fixation for shoulder girdle's fractures, orthopedic surgeons should take into account the risk for wire dislocation, and take up adequate precautions during surgery and follow-up control visits.
Foreign body migration; Kirschner wire; proximal humeral fracture; thoracoscopy; threaded wire
Combined pectoralis major disruption and proximal humeral fractures are uncommon. A simple radiologic diagnostic tool which consists of the measurement of the displacement from the humeral shaft to the lateral side of the humeral head (lateral to the outer proximal cortex) can help to diagnose this combined lesion.
Disruption; pectoralis major; proximal humerus fracture; radiographic analysis
We report a case of posterior shoulder instability following anatomic total shoulder arthroplasty (TSA). In addition, we present guidelines to aid in the management of posterior instability after TSA. A 50-year-old male underwent anatomic TSA for glenohumeral osteoarthritis. Postoperatively, the patient developed posterior instability secondary to glenoid retroversion. He did not improve despite conservative treatment. He underwent an arthroscopic posterior bone block procedure, 4-month after his index arthroplasty. At 14-month follow-up, the patient had regained near full motion and strength, and radiographs demonstrated osseous integration with no evidence of component loosening. Posterior instability following TSA is a relatively rare complication and challenging to manage. The posterior, arthroscopic iliac crest bone block grafting procedure represents a treatment option for posterior instability in the setting of a stable glenoid prosthesis following TSA.
Arthroplasty; arthroscopic bone block; glenoid; posterior instability; retroversion; shoulder
The presence of inferior scapula notching is significantly affected by the anatomy the scapula and can be influenced by the glenosphere design and position and the onlay type.
Materials and Methods:
A biomechanical study was undertaken with 13 human shoulder specimens in a robot-assisted shoulder simulator. Inferior scapula contact during adduction of the humerus was detected using a contact pressure film. Computed tomography scans with three-dimensional reconstructions of each specimen were performed.
The greatest improvement of the scapula notching angle (SNA) was achieved by simultaneous implantation of a shallow humeral onlay and an eccentric glenosphere design: 16.3-19.0° (P < 0.005). The SNA was significantly decreased by 5.8° when shifting from a 38 mm centric glenosphere to a 42 mm centric glenosphere (P < 0.005) and by 8.9° comparing the 38 mm centric glenosphere with 38 mm eccentric glenosphere (P < 0.005). The solitary implantation of a shallow onlay significantly decreased the SNA depending on the glenosphere size between 7.4° and 8.0° (P = 0.001). A more inferior position of the metaglene as well as a long scapula neck (P = 0.029) and a large lateral scapula pillar angle (P = 0.033) were correlated with a lower SNA.
This study demonstrates the importance of inferior glenosphere placement and the benefit of eccentric glenosphere and shallow humeral cup design to reduce the adduction deficit of the reverse shoulder. The presence of a short neck of the scapula can have a negative prognostic effect on inferior impingement during adduction of the arm.
Level of Evidence:
Basic Science Study
Adduction angle; biomechanics; implant configuration; reverse shoulder arthroplasty; scapula anatomy; scapula notching
The in-hospital mortality rate after total shoulder arthroplasty (TSA) is unknown. The purpose of this study is to quantify the in-patient mortality rates and associated demographic risk factors for patients undergoing a TSA from 2005 to 2011 using a comprehensive Medicare registry database.
Materials and Methods:
We conducted a retrospective review of the Medicare database within the PearlDiver database. The PearlDiver database is a publicly available Health Insurance Portability and Accountability Act-compliant national database that captures 100% of the Medicare hospital data for TSA between 2005 and 2011. Using International Classification of Diseases, Ninth Revision codes for TSA we identified a dataset of patients undergoing TSA as well as a subset of those for whom there was a death discharge (i.e., in-patient death). Risk for this outcome was further quantified by age, gender and year. Linear regression was performed to identify risk factors for the primary outcome.
A total of 101,323 patients underwent 125,813 TSAs between 2005 and 2011. There were 113 in-patient mortalities during this period. Thus the incidence of death was 0.09%. Increasing age was a significant risk factor for mortality (P = 0.03). Gender and year of procedure were not significant risk factors for mortality.
The incidence of in-patient mortality for Medicare patients undergoing TSA between 2005 and 2011 was <1 in 1000 surgeries. Increased age is a significant predictor of mortality.
Complications; in-hospital mortality; Medicare; reverse total shoulder replacement; total shoulder replacement