Edward V. Fehringer

Impact of Total Shoulder Arthroplasty on Generic and Shoulder-Specific Health-Related Quality-of-Life Measures A Systematic Literature Review and Meta-Analysis

BACKGROUND Total shoulder arthroplasty is increasingly used in the treatment of arthritis. However, the effect of total shoulder arthroplasty on health-related quality of life has not been fully established. The goal of this systematic review and meta-analysis was to characterize the change in generic and shoulder-specific health-related quality-of-life measures resulting from total shoulder arthroplasty. METHODS We identified published studies reporting preoperative and postoperative health-related quality-of-life outcomes for patients receiving total shoulder arthroplasty. Health-related quality-of-life measures were identified, and meta-analysis was used to calculate standardized mean differences (SMDs, reflective of the effect size) and 95% confidence intervals for each scale. RESULTS Twenty studies (1576 total shoulder replacements) met the inclusion criteria. Outcome measures were analyzed after an average postoperative follow-up duration of 3.7 ± 2.2 years. The Short Form-36 demonstrated significant improvement in physical component summary scores (SMD = 0.7, p < 0.001) but not in mental component summary scores (SMD = 0.2, p = 0.37). Significant improvements were observed in the visual analog scale score for pain (SMD = -2.5, p < 0.001) and scores on three shoulder-specific measures: the Constant score (SMD = 2.7, p < 0.001), American Shoulder and Elbow Surgeons score (SMD = 2.9, p < 0.001), and Simple Shoulder Test (SMD = 2.3, p < 0.001). CONCLUSIONS Total shoulder arthroplasty leads to significant improvements in scores for function and pain. Shoulder-specific measures of function consistently showed the greatest degree of improvement, with large effect sizes. Total shoulder arthroplasty also leads to significant improvements in overall physical well-being, with a moderate-to-large effect size.

The relationship of proximal locking screws to the axillary nerve during antegrade humeral nail insertion of four commercially available implants.

Objective: The purpose of this study was to determine the proximity of proximal interlocking mechanisms in 4 current antegrade humeral nails to the axillary nerve and its branches. Design: Cadaveric study. Setting: Anatomy laboratory. Main Outcome Measure: Anatomic relationships. Methods: Four humeral nail designs (labeled SS, SL, SZ, and SN) were each inserted in successive antegrade fashion in 10 cadaveric upper extremity specimens. Three variables were measured: from acromion to the axillary nerve, from acromion to entry sites of proximal locking devices, and from locking devices to axillary nerves and their branches. Results: In nail SS, the proximally directed oblique locking screw came into contact with the ascending branch of the axillary nerve in 6 of 10 specimens. Mean distance from spiral blades in nails SS and SL were 26 mm to the axillary nerve and 16 mm to its ascending branch. Interlocking screws for nails SZ, SN, and SL did not violate the axillary nerve or its branches in any specimen. Mean distance from lateral acromion to the axillary nerve measured 58.7 mm. Conclusion: Nail SS’s oblique locking screw may injure the ascending branch of the axillary nerve. Three of the 4 nails tested did not endanger the axillary nerve. However, when transverse proximal locking screws are inserted from a lateral-to-medial direction, they may endanger an arborized axillary nerve. Blunt dissection should be performed with a visible path to bone before instrumentation to reduce the risk of axillary nerve injury.

Early Detection and Treatment of Wear Particle-Induced Inflammation and Bone Loss in a Mouse Calvarial Osteolysis Model Using HPMA Copolymer Conjugates

Wear particle-induced inflammation is considered to be the major cause of aseptic implant loosening and clinical failure after total joint replacement. Due to the frequent absence of symptoms, early detection and intervention prior to implant failure presents a significant challenge. To address this issue, a N-(2-hydroxypropyl)methacrylamide (HPMA) copolymer-based optical imaging contrast agent (P-IRDye) was developed and used for the detection of wear particle-induced inflammation employing a murine calvaria osteolysis model. The particle-induced osteolysis of calvaria was evaluated by H&E, tartrate-resistant acid phosphatase (TRAP) staining and μ-CT after necropsy. One-day post particle implantation, P-IRDye was administrated to the mice via tail vein injection. Live imaging of the animals 6 days after implantation revealed the preferential distribution and sustained retention of the macromolecular contrast agent at the site of particle implantation. Immunohistochemical staining and FACS analyses of the calvaria-associated soft tissue revealed extensive uptake of the HPMA copolymer by F4/80, Ly-6G (Gr1) and CD11c positive cells, which accounts for the retention of the macromolecular probes at the inflammatory sites. To test the potential of the system for therapeutic intervention, an acid-labile HPMA copolymer-dexamethasone conjugate (P-Dex) was prepared and shown to prevent the particle-induced inflammation and bone damage in the calvaria osteolysis model.

Angular-Stable Locked Intramedullary Nailing of Two-Part Surgical Neck Fractures of the Proximal Part of the Humerus A Multicenter Retrospective Observational Study

BACKGROUND The ideal fixation technique for the treatment of proximal humeral fractures remains unclear. In the present study, we evaluated the experience of three surgeons with the treatment of two-part surgical neck fractures with angular-stable intramedullary fixation. METHODS Forty-eight patients with forty-eight Neer two-part surgical neck proximal humeral fractures were managed with locked angular-stable intramedullary nail fixation by three surgeons. Shoulder pain and outcomes were quantified with Constant scores and standard radiographs. RESULTS Thirty-eight patients (including twenty-eight female patients and ten male patients) with a mean age of sixty-five years were followed for at least twelve months (mean, twenty months; range, twelve to thirty-six months). All fractures healed primarily. The mean follow-up Constant score (and standard deviation) was 71 ± 12 points (range, 37 to 88 points), with a mean age-adjusted Constant score of 97% (range, 58% to 119%). The mean Constant pain score was 13 ± 2.2 (possible range, 0 to 15 points, with 15 points representing no pain). The mean forward flexion was 132° ± 22°. All fractures but one healed with a neck-shaft angle of ≥125°. CONCLUSIONS Patients who were managed with locked angular-stable intramedullary nailing of two-part surgical neck proximal humeral fractures via an articular entry point had reliable fracture-healing, favorable clinical outcomes, and little residual shoulder pain.

Bone presence between the central peg's radial fins of a partially cemented pegged all poly glenoid component suggest few radiolucencies.

BACKGROUND Cement penetration problems and/or cement-induced bone necrosis may contribute to glenoid component failures. An all polyethylene component was developed that promotes biologic fixation between radial fins of its central peg and utilizes minimal cement fixation for its peripheral pegs, but it has little published data. We hypothesized better bone presence between the radial fins would be associated with less overall radiolucencies. This studys purpose was to utilize computed tomography (CT) and plain films to assess for bone between the central pegs radial fins and to assess overall component radiolucencies. MATERIALS AND METHODS Thirty-five of 48 consecutively performed total shoulder arthroplasties (TSA) for primary glenohumeral osteoarthritis were in patients able to participate a minimum 2 years after surgery. All had reamed humeral head bone packed between radial fins of the central peg and minimal cement for the peripheral pegs. Thin cut (0.625 mm) CT scans, standardized plain films, Simple Shoulder Tests (SST), and Constant scores were obtained. A musculoskeletal radiologist calculated Yian CT scores, bone presence between fins on CT, and Lazarus radiolucency scores. RESULTS At a mean of 43 months, by CT: 1) better Yian scores correlated with more bone between fins, and 2) bone was present in 6/6 inter-fin compartments in 23/35 shoulders, averaging 4.5/6 overall. Mean Lazarus radiolucency score was 0.45. Mean SST and Constant scores were 10.3 and 81.3, respectively. CONCLUSION TSA utilizing autologous bone in inter-fin compartments of the central peg and minimal peripheral peg cement maintained bone presence a minimum 2 years post-op. More bone imparted fewer overall component radiolucencies.

Outcomes Following Distal Humeral Fracture Fixation with an Extensor Mechanism-On Approach

BACKGROUND Distal humeral fractures have traditionally been managed with surgical approaches that disrupt the extensor mechanism. We hypothesized that an extensor mechanism-on approach for operative fixation of distal humeral fractures with parallel or orthogonal plate constructs would allow excellent healing, a motion arc of the elbow exceeding 100°, and maintenance of extensor mechanism strength. METHODS Distal humeral open reduction and internal fixation (ORIF) was performed with either orthogonal or parallel plate constructs in seventy-nine elbows. Thirty-seven elbows were fixed via an extensor mechanism-on surgical approach, and twenty-four of them were available for additional evaluation. Radiographs as well as MEPI (Mayo Elbow Performance Index), DASH (Disabilities of the Arm, Shoulder and Hand), and SF-36 (Short Form-36) scores were obtained. RESULTS All thirty-seven fractures healed primarily. Three elbows underwent later release because of stiffness. The median arc of elbow motion was 126° (range, 60° to 141°). The mean MEPI was 91.5 points and the mean DASH score was 15.9 points, indicating excellent scores with mild impairment. The median percent loss of triceps strength was 10% (range, 0% to 49%) compared with the contralateral, normal elbow. CONCLUSIONS Open treatment of distal humeral fractures with an extensor mechanism-on approach results in excellent healing, a mean elbow flexion-extension arc exceeding 100°, and maintenance of 90% of elbow extension strength compared with that of the contralateral, normal elbow.

The radiographic acromiohumeral interval is affected by arm and radiographic beam position

ObjectiveThe objective was to determine whether arm and radiographic beam positional changes affect the acromiohumeral interval (AHI) in radiographs of healthy shoulders.Materials and methodsControlling for participant’s height and position as well as radiographic beam height and angle, from 30 right shoulders of right-handed males without shoulder problems four antero-posterior (AP) radiographic views each were obtained in defined positions. Three independent, blinded physicians measured the AHI to the nearest millimeter in 120 randomized radiographs. Mean differences between measurements were calculated, along with a 95% confidence interval.ResultsControlling for observer effect, there was a significant difference between AHI measurements on different views (p < 0.01). All pair-wise differences were statistically significant after adjusting for multiple comparisons (all p values < 0.01).ConclusionsEven in healthy shoulders, small changes in arm position and radiographic beam orientation affect the AHI in radiographs.

Prevention of Orthopedic Device-Associated Osteomyelitis Using Oxacillin-Containing Biomineral-Binding Liposomes

ABSTRACTPurposeTo develop novel biomineral-binding liposomes (BBL) for the prevention of orthopedic implant associated osteomyelitis.MethodsA biomineral-binding lipid, alendronate-tri(ethyleneglycol)-cholesterol conjugate (ALN-TEG-Chol), was synthesized through Cu(I)-catalyzed Huisgen 1,3-dipolar cycloaddition (a versatile click reaction). Mixing with other excipients, the new lipid was used to develop BBL. Thermodynamic behavior was studied by differential scanning calorimetry (DSC). In vitro biomineral-binding potential and kinetics were evaluated on hydroxyapatite (HA, a widely used material for orthopedic implant devices) particles. Oxacillin was encapsulated into BBL and used for in vitro evaluation in preventing Staphylococcus aureus biofilm formation.ResultsDSC analysis showed that ALN-TEG-Chol could inhibit the phase transition of liposomes by reducing its cooperativity, yielding liposomes with thermodynamic stability similar to liposomes containing regular cholesterol. BBL showed fast and strong binding ability to HA. Oxacillin-loading BBL demonstrated significantly better preventive efficacy against bacteria colonization when challenged with S. aureus isolate, implying its potential in preventing orthopedic implant associated osteomyelitis.ConclusionsIn this proof of concept study, novel BBL has been successfully developed and validated for reducing the frequency of implantable device-related infections.

Rheumatoid arthritis patients are not at increased risk for 30-day cardiovascular events, infections, or mortality after total joint arthroplasty

IntroductionSerious infection, cardiovascular disease, and mortality are increased in rheumatoid arthritis (RA). Whether RA affects the risk for these complications after total joint arthroplasty (TJA) is unknown, we hypothesize that it does. We compared the occurrence of 30-day postoperative complications and mortality in a large cohort of RA and osteoarthritis (OA) patients undergoing hip or knee TJA.MethodsAnalyses included 7-year data from the Veterans Affairs Surgical Quality Improvement Program. The 30-day complications were compared by diagnosis by using logistic regression, and long-term mortality was examined by using Cox proportional hazards regression. All analyses were adjusted for age, sex, and clustering by surgical site. Additional covariates included sociodemographics, comorbidities, health behaviors, and operative risk factors.ResultsThe 34,524 patients (839 RA, 33,685 OA) underwent knee (65.9%) or hip TJA. Patients were 95.7% men with a mean (SD) age of 64.4 (10.7) years and had 3,764 deaths over a mean follow-up of 3.7 (2.3) years. Compared with OA patients, those with RA were significantly more likely to require a return to the operating room (odds ratio (OR), 1.45 (95% CI, 1.08 to 1.94), but had similar rates of 30-day postoperative infection, OR 1.02 (0.72 to 1.47), cardiovascular events, OR 0.69 (0.37 to 1.28), and mortality, OR 0.94 (0.38 to 2.33). RA was associated with a significantly higher long-term mortality; hazard ratio (HR), 1.22 (1.00 to 1.49).ConclusionIn this study of US veterans, RA patients were not at an increased risk for short-term mortality or other major complications after TJA, although they returned to the operating room more often and had increased long-term mortality.

Short, Locked Humeral Nailing via Neviaser Portal: An Anatomic Study

Objective: Supraspinatus tendon trauma may contribute to residual shoulder pain after nail fixation for proximal humeral fractures. Some have proposed a more medial starting point for humeral nail insertion to avoid cuff tendon footprint damage. We hypothesized that percutaneous nail insertion via Neviaser portal would not only be possible, but would avoid tendon trauma, while sacrificing articular cartilage. Materials and Methods: Under c-arm guidance and in percutaneous fashion, we nailed 16 consecutive complete (head and neck, etc, intact) specimen right proximal humeri with locked short humeral nails (Aequalis) via Neviaser portal. Each shoulder was dissected to study the damage to the rotator cuff and long head of the biceps tendons as well as to the articular surfaces. We measured the humeral–thoracic abduction arc before the damaged articular surface contacted the superior glenoid. There were 5 male specimens and 11 female specimens with a mean age of 83 years at the time of death. Results: We successfully inserted 15 of 16 humeral nails through this percutaneous approach. No supraspinatus tendon or long head of the biceps tendon was damaged. All nails passed entirely through supraspinatus muscle belly. Thirteen of 15 starting points were entirely on articular surface. Mean arc of abduction before superior glenoid contact was 76 degrees (range, 50 degrees–130 degrees). Mean distance from the edge of the articular surface to the most lateral part of the nail insertion was 11 mm (0–25 mm). Conclusions: Short, locked humeral nail insertion is possible in percutaneous fashion via Neviaser portal without tendon injury. However, successful insertion comes at the cost of articular cartilage damage.