Glenoid baseplate fixation using hybrid configurations of locked and unlocked peripheral screws.

BACKGROUND: The use of peripheral locked screws has reduced glenoid baseplate failure rates in reverse shoulder arthroplasty. However, situations may arise when one or more non-locked screws may be preferred. We aimed to determine if different combinations of locked and non-locked screws significantly alter acute glenoid baseplate fixation in a laboratory setting. MATERIALS AND METHODS: Twenty-eight polyurethane trabecular bone surrogates were instrumented with a center screw-type glenoid baseplate and fixated with various combinations of peripheral locked and non-locked screws (1-, 2-, 3- and 4-locked con). Each construct was tested through a 55° arc of abduction motion generating compressive and shear forces across the glenosphere. Baseplate micromotion (µm) was recorded throughout 10,000 cycles for each model. RESULTS: All constructs survived 10,000 cycles of loading without catastrophic failure. One test construct in the 1-locked fixation group exhibited a measured micromotion >150 µm (177.6 µm). At baseline (p > 0.662) and following 10,000 cycles (p > 0.665), no differences were observed in baseplate micromotion for screw combinations that included one, two, three and four peripheral locked screws. The maximum difference in measured micromotion between the extremes of groups (1-locked and 4-locked) was 29 µm. CONCLUSIONS: Hybrid peripheral screw fixation using combinations of locked and non-locked screws provides secure glenoid baseplate fixation using a polyurethane bone substitute model. Using a glenosphere with a 10-mm lateralized center of rotation, hybrid baseplate fixation maintains micromotion below the necessary threshold for bony ingrowth. LEVEL OF EVIDENCE: N/A/, basic science investigation.

Observation of initial postoperative radiolucent lines using a modern pegged-glenoid design.

PURPOSE: 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. RESULTS: 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). CONCLUSIONS: 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.

Scapholunate instability after distal radius volar plating.

BACKGROUND: Prior to volar locked plating and early motion protocols, ligamentous injuries incidentally associated with distal radius fractures may have been indirectly treated with immobilization. Our goal was to determine the prevalence of scapholunate instability in our population, while identifying those who may have had progression of instability. METHODS: We retrospectively reviewed 221 distal radius fractures treated with a volar locking plate during a 6-year period. Average patient age was 59 years. Standard posteroanterior and lateral radiographs from the first and last postoperative visits were analyzed for scapholunate instability, using the criteria of scapholunate gap ≥3 mm and scapholunate angle ≥60°. RESULTS: Six patients (3 %) met neither or only one criterion for instability at the first postoperative visit and did not have ligament repair and then went on to meet both criteria at the last postoperative visit after an early motion protocol. Seven patients (3 %) met both criteria at the first and last postoperative visits and did not have ligament repair. Five patients (2 %) underwent primary scapholunate ligament repair at the time of distal radius fixation. CONCLUSIONS: In our representative population, scapholunate instability was uncommon, either from initial injury or possible progression of occult ligament injury, despite early motion without operative treatment of the ligament. Thus, we did not find strong evidence for routinely delaying motion or pursuing further workup. When early radiographs clearly demonstrate acute scapholunate instability, more aggressive treatment may be appropriate for selected patients.

Anatomic and Reverse Total Shoulder Arthroplasty in Patients Older Than 80 Years.

Anatomic total shoulder arthroplasty (TSA) and reverse total shoulder arthroplasty (RSA) are routinely performed in patients older than 80 years. Often unaware of the differences between the 2 procedures, patients may expect similar outcomes from these procedures. This article reports the outcomes of primary TSA and RSA in patients older than 80 years, with attention directed toward differences in outcomes between the procedures. The authors evaluated a consecutive series of patients who were at least 80 years old and were treated with primary shoulder arthroplasty and had a minimum follow-up of 2 years. Of these patients, 18 underwent primary TSA for osteoarthritis and 33 underwent primary RSA for rotator cuff tear arthropathy. Pain scores, function scores, and range of motion were evaluated preoperatively and at final follow-up. Perioperative and postoperative complications, transfusion rates, length of stay, and subjective satisfaction with the outcome were reported. In these patients, TSA and RSA were similarly effective in improving pain scores, functional scores, and range of motion measurements. Patients who had TSA reported significantly greater satisfaction with surgery and had superior American Shoulder and Elbow Society total and function scores, forward elevation, and external rotation, but similar net improvement from preoperative levels. Although no significant differences were shown in complications, length of stay, or requirement for transfusion, patients treated with RSA had higher rates of transfusion and postoperative complications. Both procedures were similarly effective treatments for patients older than 80 years and showed similar improvements in pain, function, and motion. Patients undergoing RSA were less likely to have good to excellent results, with higher complication and transfusion rates.

The effect of glenoid bone loss on reverse shoulder arthroplasty baseplate fixation.

BACKGROUND: Glenoid bone loss is commonly observed during primary and revision reverse shoulder arthroplasty. Glenoid baseplates are often implanted with incomplete glenoid bone support. The purpose of this study was to evaluate the glenoid component fixation of the glenoid baseplate with variable amounts of incomplete coverage. METHODS: Twenty-eight polyurethane trabecular bone surrogates were instrumented with the same center screw-type glenoid baseplate with 4 peripheral 5.0-mm locking screws in a glenoid bone loss model consisting of 25%, 50%, 75%, and 100% coverage. Each construct was tested through a 55° arc of motion with both compressive and shear forces across the glenosphere. Baseplate micromotion was recorded throughout 10,000 cycles for each model. RESULTS: There was no significant difference in baseline micromotion between the 4 experimental groups (P = .099). In the 25% baseplate coverage group, 3 of 7 exhibited micromotion above the 150-µm threshold (624.5, 469.1, and 712.1 µm) during cyclic loading. After 10,000 cycles of loading, the 25% coverage group exhibited significantly more micromotion than the 50% (P = .049), 75% (P = .026), and 100% (P = .040) coverage groups. There was no significant difference between the 100%, 75%, and 50% coverage groups (P = 1.00). CONCLUSIONS: Glenoid baseplate fixation in the setting of glenoid bone loss is no different when 50%, 75%, or 100% of the baseplate is supported by glenoid bone. Bone loss resulting in only 25% coverage results in significantly greater micromotion, often above the 150-µm threshold.

Tuberosity healing after reverse shoulder arthroplasty for acute proximal humerus fractures: the "black and tan" technique.

BACKGROUND: Reverse shoulder arthroplasty has seen increased use for management of complex proximal humeral fractures in the elderly. Recent evidence has shown that tuberosity healing leads to improved active range of motion and functional outcomes. The purpose of this study was to report on the radiographic and clinical outcomes of a consecutive series of patients having undergone reverse shoulder arthroplasty for fracture utilizing the "black and tan" method--a hybrid cementation-impaction grafting technique that uses autogenous cancellous bone graft to create an interface between the proximal cement mantle and the area of tuberosity repair. METHODS: Twenty-five patients (average age, 77 years; range, 63-88 years) were included in the analysis with a mean follow-up of 17 months. All patients underwent reverse shoulder arthroplasty for a complex proximal humerus fracture using the black and tan technique. RESULTS: The tuberosity healing rate was 88%. At final follow-up, mean active elevation was 117° ± 23°, mean abduction was 86° ± 16°, and mean external rotation was 29° ± 18°. External rotation strength averaged 4.9 ± 0.2. The Simple Shoulder Test and Single Assessment Numeric Evaluation scores averaged 7 and 76, respectively. The mean American Shoulder and Elbow Surgeons total score was 71; visual analog scale score for pain, 2; and visual analog scale score for function, 7. Of the 25 patients, 21 (84%) rated their satisfaction with the surgery as excellent or good. CONCLUSIONS: The black and tan technique together with standard suture repair and an implant with features that support tuberosity repair results in a high tuberosity healing rate with restoration of external rotation after reverse shoulder arthroplasty for fracture.

Risk factors for complications of open trigger finger release.

BACKGROUND: Open trigger finger release is generally considered a simple low-risk procedure. Reported complication rates vary widely from 1 to 43 %, mostly based on small studies. Our goal was to determine the incidence of complications in a large consecutive series, while also identifying potential risk factors. METHODS: All open trigger finger releases performed from 2006 to 2009 by four fellowship-trained hand surgeons at a single institution were retrospectively reviewed. There were 795 digits released in 543 patients. Complications were defined as signs or symptoms requiring further treatment and/or considered unresolved by 1 month postoperatively. Complications requiring operative intervention were regarded as major. Multivariable analysis was performed to determine possible risk factors for complications. RESULTS: There were 95 documented complications among 795 digits (12 %). The most common complications involved persistent pain, stiffness, or swelling, persistent or recurrent triggering, or superficial infection. Most were treated nonoperatively with observation, therapy, steroid injection, or oral antibiotics. There were 19 reoperations (2.4 %), mostly including revision release, tenosynovectomy, and irrigation and debridement. Male gender, sedation, and general anesthesia were independently associated with complications, while age, diabetes, hypothyroidism, recent injection, and concurrent procedures were not associated. CONCLUSIONS: Open trigger finger release is generally a low-risk procedure, although there is potential for complications, some requiring reoperation. Male gender, sedation, and general anesthesia may be associated with greater risk. Surgeons should be careful to thoroughly discuss the risk of both major and minor complications when counseling patients.

Cerebral desaturation events in the beach chair position: correlation of noninvasive blood pressure and estimated temporal mean arterial pressure.

BACKGROUND: Cerebral oximetry (rSO2) has emerged as an important tool for monitoring of cerebral perfusion during surgery. High rates of cerebral desaturation events (CDEs) have been reported during surgery in the beach chair position. However, correlations have not been made with blood pressure measured at the cerebral level. The purpose of this study was to examine the correlations between brachial noninvasive blood pressure (NIBP) and estimated temporal mean arterial pressure (eTMAP) during CDEs in the beach chair position. METHODS: Fifty-seven patients underwent elective shoulder surgery in the beach chair position. Values for eTMAP, NIBP, and rSO2 were recorded supine (0°) after induction and when a CDE occurred in the 70° beach chair position. Twenty-six patients experienced 45 CDEs, defined as a 20% drop in rSO2 from baseline. RESULTS: Median reduction in NIBP, eTMAP, and rSO2 from baseline to the CDE were 48.2%, 75.5%, and 33.3%, respectively. At baseline, there was a significant weak negative correlation between rSO2 and NIBP (rs = -0.300; P = .045) and no significant association between rSO2 and eTMAP (rs = -0.202; P = .183). During CDEs, there were no significant correlations between rSO2 and NIBP (rs = -0.240; P = .112) or between rSO2 and eTMAP (rs = -0.190; P = .212). No significant correlation between the decrease in rSO2 and NIBP (rs = 0.064; P = .675) or between rSO2 and eTMAP (rs = 0.121; P = .430) from baseline to CDE was found. CONCLUSION: NIBP and eTMAP are unreliable methods for identifying a CDE in the beach chair position. Cerebral oximetry provides additional information to the values obtained from NIBP and eTMAP, and all should be considered independently and collectively.

Functional internal rotation after shoulder arthroplasty: a comparison of anatomic and reverse shoulder arthroplasty.

BACKGROUND: Recovery of functional internal rotation after primary shoulder arthroplasty is essential to perform many important activities of daily living. Functional internal rotation is typically reported as it relates to clinical examination findings of motion (posterior reach) and lift-off or belly-press tests. A more detailed evaluation of functional recovery of internal rotation after primary anatomic total shoulder arthroplasty (TSA) and reverse shoulder arthroplasty (RSA) is needed. METHODS: A retrospective review of patients treated with primary TSA (n = 132) and RSA (n = 91) with a minimum 2-year follow-up was performed. Subanalysis of revision RSA (n = 24) and primary RSA was performed. Active range of motion, subjective internal rotation motion, manual internal rotation strength, and specific questions related to internal rotation function isolated from the Simple Shoulder Test (SST) and American Shoulder and Elbow Surgeons (ASES) functional questionnaires were reviewed. RESULTS: Compared with RSA, TSA patients could more likely reach the small of the back (SST) and wash the back/fasten bra (ASES). Active internal rotation motion, SST score, ASES score, and subjective internal rotation were greater after TSA. No significant difference was observed with respect to managing toileting between cohorts. Revision RSA patients were less likely to be able to wash the back/fasten bra (ASES) and easily manage toileting (ASES) compared with primary RSA patients. CONCLUSION: Primary anatomic shoulder arthroplasty yields greater functional internal rotation than does primary RSA, with either procedure being effective at managing toileting. Patient education regarding activities of daily living related to internal rotation can be predicted.

Association between temporal mean arterial pressure and brachial noninvasive blood pressure during shoulder surgery in the beach chair position during general anesthesia.

BACKGROUND: Estimation of cerebral perfusion pressure during elective shoulder surgery in the beach chair position is regularly performed by noninvasive brachial blood pressure (NIBP) measurements. The relationship between brachial mean arterial pressure and estimated temporal mean arterial pressure (eTMAP) is not well established and may vary with patient positioning. Establishing a ratio between eTMAP and NIBP at varying positions may provide a more accurate estimation of cerebral perfusion using noninvasive measurements. METHODS: This prospective study included 57 patients undergoing elective shoulder surgery in the beach chair position. All patients received an interscalene block and general anesthesia. After the induction of general anesthesia, values for eTMAP and NIBP were recorded at 0°, 30°, and 70° of incline. RESULTS: A statistically significant, strong, and direct correlation between NIBP and eTMAP was found at 0° (r = 0.909, P ≤ .001), 30° (r = 0.874, P < .001), and 70° (r = 0.819, P < .001) of incline. The mean ratios of eTMAP to NIBP at 0°, 30°, and 70° of incline were 0.939 (95% confidence interval [CI], 0.915-0.964), 0.738 (95% CI, 0.704-0.771), and 0.629 (95% CI, 0.584-0.673), respectively. There was a statistically significant decrease in the eTMAP/NIBP ratio as patient incline increased from 0° to 30° (P < .001) and from 30° to 70° (P < .001). CONCLUSION: The eTMAP-to-NIBP ratio decreases as an anesthetized patient is placed into the beach chair position. Awareness of this phenomenon is important to ensure adequate cerebral perfusion and prevent hypoxic-related injuries.

Speed of recovery after shoulder arthroplasty: a comparison of reverse and anatomic total shoulder arthroplasty.

BACKGROUND: Whereas patient expectations after anatomic total shoulder arthroplasty (TSA) and reverse shoulder arthroplasty (RSA) relate to sustained improvements in pain, function, and motion, the time necessary to reach these goals is unclear. Our purpose was to investigate the speed of recovery and to compare the effectiveness of primary TSA and RSA. METHODS: We analyzed (preoperative, 3 month, 6 month, 1-year, and 2-year scores) pain scores, functional scores, and motion for 122 patients treated with primary RSA and 166 patients treated with primary TSA with a minimum of 1 year of follow-up. Comparisons were made to determine the effectiveness of treatment, time required to reach a plateau in improvement, and percentage of overall improvement at 3 and 6 months. RESULTS: Significant improvements were observed for both TSA and RSA at all intervals (P < .001), except with internal rotation for RSA. Pain relief was rapid after both TSA and RSA. TSA patients reached a consistent plateau for pain and function by 6 months and for shoulder elevation by 1 year. RSA patients demonstrated variability with multiple false plateau points. By 6 months, TSA patients had achieved 90% to 100% of functional improvement, whereas RSA patients reached 72% to 91%. The effectiveness of TSA was greater than that of RSA for all measures with the exception of elevation and abduction. CONCLUSION: Whereas patients treated with primary TSA and RSA can expect rapid improvements in pain, those treated with TSA can anticipate a more consistent and effective recovery of pain, function, and shoulder rotation. Patients receiving RSA can expect a variable length of recovery with greater improvements in forward elevation and abduction.

Accuracy of patient-specific guided glenoid baseplate positioning for reverse shoulder arthroplasty.

BACKGROUND: The accuracy of reproducing a surgical plan during shoulder arthroplasty is improved by computer assistance. Intraoperative navigation, however, is challenged by increased surgical time and additional technically difficult steps. Patient-matched instrumentation has the potential to reproduce a similar degree of accuracy without the need for additional surgical steps. The purpose of this study was to examine the accuracy of patient-specific planning and a patient-specific drill guide for glenoid baseplate placement in reverse shoulder arthroplasty. METHODS: A patient-specific glenoid baseplate drill guide for reverse shoulder arthroplasty was produced for 14 cadaveric shoulders based on a plan developed by a virtual preoperative 3-dimensional planning system using thin-cut computed tomography images. Using this patient-specific guide, high-volume shoulder surgeons exposed the glenoid through a deltopectoral approach and drilled the bicortical pathway defined by the guide. The trajectory of the drill path was compared with the virtual preoperative planned position using similar thin-cut computed tomography images to define accuracy. RESULTS: The drill pathway defined by the patient-matched guide was found to be highly accurate when compared with the preoperative surgical plan. The translational accuracy was 1.2 ± 0.7 mm. The accuracy of inferior tilt was 1.2° ± 1.2°. The accuracy of glenoid version was 2.6° ± 1.7°. CONCLUSION: The use of patient-specific glenoid baseplate guides is highly accurate in reproducing a virtual 3-dimensional preoperative plan. This technique delivers the accuracy observed using computerized navigation without any additional surgical steps or technical challenges.

Prevention and treatment of elbow stiffness: a 5-year update.

Elbow stiffness is a challenging and common problem faced by upper extremity surgeons. Although functional improvements can be made with both nonsurgical and surgical management strategies, physicians must remain vigilant with efforts to prevent stiffness before it starts. Recent advancements in the biology and pathology of elbow contracture have led to improved understanding of this difficult problem, and they may lead to future breakthroughs in the prevention and treatment of elbow stiffness. This article serves as an update to our previous review of elbow stiffness, focusing on recent advancements in the past 5 years, as well as updating our current algorithm for treatment.