Faculty Bibliography

An accelerometer attached to the anterior proximal tibia was investigated as an evaluation of knee stability of Total Knee Arthroplasty (TKA) patients while performing daily activities. Acceleration data of 38 TKA knees with a minimum follow up of 6months were compared with 34 control knees. The activities performed were: walking three steps forward and coming to a sudden stop; turning in the direction of non-tested knee; sit-to-stand; and stepping up and down from a 7 inch step. The acceleration results showed significant differences between TKA and controls while stepping down and while turning in the non-tested knee direction. The higher accelerations with the TKA group may have represented an objective measure of stability, even if this was not directly discernible to the patient.

PURPOSE: To investigate the effects of age on the clinical, functional, and radiographic outcomes of patients with proximal humerus fractures treated operatively with locking plates. METHODS: Between February 2003 and July 2012, all patients who sustained a proximal humerus fracture who presented to our institution were enrolled into a database. Patients were followed up at 1, 6, 12, 26, and 52 weeks postoperatively with physical examination and radiographs. Validated functional outcomes scores were collected at 6 and 12 months. Complications were recorded as they occurred. Statistical analysis was conducted to assess for functional, physical, or radiographic differences between patients age younger than 65 and patients age 65 or older. RESULTS: Of the 147 consecutive patients treated operatively for a proximal humerus fracture, 115 (78%) patients with an average follow-up of 16 months met the inclusion criteria for this study. The young cohort (patients < 65) included 70 patients with an average age of 53, whereas the elderly cohort (patients >/= 65) included 45 patients with an average age of 73. The older cohort had significantly more women (P = .04), but there was no statistical difference in fracture type between the age groups. There were no differences in the radiographic measures of screw penetration, humeral head height, and neck-shaft angle between the age groups. There were no differences in physical examination scores between the age groups. There were no significant differences in functional outcomes or complication rates between the age groups. CONCLUSION: Treating proximal humerus fractures operatively with locked plates can overcome the challenges of poor bone quality that often occur with increasing age. Age should not play a significant role in the decision-making process for treating proximal humerus fractures that would otherwise be indicated for surgical fixation.

BACKGROUND: Injection to the acromioclavicular (AC) joint can be both diagnostic and therapeutic. PURPOSE: The purpose of this study was to evaluate the accuracy of in vivo AC joint injections. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Thirty patients with pain localized to the AC joint were injected with 1 mL of 1% lidocaine and 0.5 mL of radiographic contrast material (Isovue). Radiographs of the AC joint were taken after the injection. Each radiograph was reviewed by a musculoskeletal radiologist and graded as intra-articular, extra-articular, or partially intra-articular. RESULTS: Of the 30 injections performed, 13 (43.3%) were intra-articular, 7 (23.3%) were partially articular, and 10 (33.3%) were extra-articular. When the intra-articular and the partially articular groups were combined, 20 patients (66.7%) had some contrast dye in the AC joint. CONCLUSION: This study demonstrates that despite the relatively superficial location of the AC joint, the clinical accuracy of AC joint injections remains relatively low.

The education of orthopaedic residents is an important responsibility shared by all those involved in residency training. The education of orthopaedic residents begins with the selection process, which recognizes the importance of choosing qualified individuals who can successfully complete the training program. Education during the 5 years of required training entails the acquisition of a body of knowledge, the development of surgical skills, and the exhibition of a level of professionalism consistent with being a physician and surgeon. Residency training also requires an evaluation of performance and, when necessary, measures to improve performance or correct inappropriate behaviors. The goal at the end of the 5-year training period is to have well-qualified, skilled, and knowledgeable orthopaedic surgeons who can enter practice and provide the highest level of patient care.

Post-patellectomy patients represent a specific subgroup of patients that may develop arthritis and persistent knee pain and potentially require treatment with total knee arthroplasty. This article reviews the treatment and functional outcomes following total knee arthroplasty in patients with prior patellectomy. A case report is presented as an example of the clinical management of a post-patellectomy patient with significant knee pain and disability treated with total knee arthroplasty. Emphasis will be placed in decision- making, specifically with the use of a posterior stabilized implant. In addition, postoperative strengthening of the quadriceps is essential to compensate for the lack of the patella and increase the success of total knee arthroplasty in this subgroup of patients.

Insufficiency fractures present a significant problem in patients with osteoporosis. We report a case of bilateral iliac wing insufficiency fracture following low energy injury in an 87-year-old osteoporotic woman occurring 2 weeks after primary total hip arthroplasty. There are only a few reports of insufficiency fractures involving the ilium in the literature, and diagnosis has proven challenging, as radiographs are often negative at symptom onset. Magnetic resonance or radionuclide imaging is generally necessary for definitive diagnosis. This case highlights the importance of careful perioperative management of patients with osteoporosis.

PURPOSE: This study quantifies the ability of humeral retroversion, glenoid tilt, bone graft, and varying prosthesis design parameters to restore anatomic muscle length and deltoid wrapping with reverse shoulder arthroplasty. METHODS: A computer model simulated abduction and internal and external rotation for a normal shoulder, the RSP reverse shoulder, the Equinoxe reverse shoulder, and the Grammont reverse shoulder when implanted using various implantation methods. The length of eight different muscles and the deltoid wrapping angle were quantified to evaluate the ability of each implantation method and design to restore anatomic muscle tensioning. RESULTS: Each reverse shoulder shifted the center of rotation medially and inferiorly relative to the normal shoulder and caused a corresponding shift in the position of the humerus. Each reverse shoulder elongated each head of the deltoid and shortened the internal and external rotators relative to the normal shoulder. The surgical techniques and prosthesis designs, which resulted in a more lateral humeral position, were associated with more deltoid wrapping and better tensioning of the anterior and posterior shoulder muscles. CONCLUSIONS: Muscle tensioning and deltoid wrapping can be substantially altered by surgical implantation meth- ods using the Grammont reverse shoulder. However, the results of this study demonstrate that more anatomic muscle tensioning and improved deltoid wrapping are achieved using alternative prosthesis designs that better restore the lateral position of the humerus.

PURPOSE: The purpose of this study is to validate a reverse shoulder computer impingement model and quantify the impact of implant position on scapular impingement by comparing it to that of a radiographic analysis of 256 patients who received the same prosthesis and were followed postoperatively for an average of 22.2 months. METHODS: A geometric computer analysis quantified anterior and posterior scapular impingement as the humerus was internally and externally rotated at varying levels of abduction and adduction relative to a fixed scapula at defined glenoid implant positions. These impingement results were compared to radiographic study of 256 patients who were analyzed for notching, glenoid baseplate position, and glenosphere overhang. RESULTS: The computer model predicted no impingement at 0 degrees humeral abduction in the scapular plane for the 38 mm, 42 mm, and 46 mm devices when the glenoid baseplate cage peg is positioned 18.6 mm, 20.4 mm, and 22.7 mm from the inferior glenoid rim (of the reamed glenoid) or when glenosphere overhang of 4.6 mm, 4.7 mm, and 4.5 mm was obtained with each size glenosphere, respectively. When compared to the radiographic analysis, the computer model correctly predicted impingement based upon glenoid base- plate position in 18 of 26 patients with scapular notching and based upon glenosphere overhang in 15 of 26 patients with scapular notching. CONCLUSIONS: Reverse shoulder implant positioning plays an important role in scapular notching. The results of this study demonstrate that the computer impingement model can effectively predict impingement based upon implant positioning in a majority of patients who developed scapular notching clinically. This computer analysis provides guidance to surgeons on implant positions that reduce scapular notching, a well-documented complication of reverse shoulder arthroplasty.

BACKGROUND: Shoulder arthroplasty provides predictable pain relief and functional improvement of the shoulder for glenohumeral disease. With recent emphasis on health economic planning and rising patient expectation, physicians are encouraged to adopt more evidence-based strategies for decision-making. In the context of shoulder arthroplasty, surgeon preference and bias may play a large role in the choice of the procedure performed. The purpose of this study is to objectively examine the perceived differences and similarities, from the surgeon's perspective, between total shoulder arthroplasty (TSA) and hemiarthroplasty anticipated outcomes. METHODS: We conducted a web-based survey that asked surgeons to weigh the relative values of these procedures in relation to one another. Within the survey, there were numerous variables in which the surgeon was asked to choose the preferred surgical outcome. Ninety-eight surgeons responded to the survey. The average age was 51.7 years. RESULTS: Surgeons in our study chose pain relief and improved ROM as a more likely outcome in TSA than any level of complication and as a more likely out-come than improved strength compared to hemiarthroplasty. These results emphasized the perception amongst the polled surgeons that TSA is a preferred treatment option for patients who expect a high level of pain relief and ROM even at the expense of a decreased strength. CONCLUSION: This study is a first step in the construction of a patient oriented model for treatment decisions. With this information, we may be better able to tailor our patients' needs and wishes to the procedures that most predictably result in the outcomes they desire.

Subscapularis tenotomy for total shoulder arthroplasty has been the standard approach for shoulder surgeons that utilize the deltopectoral approach. The risk of subscapularis insufficiency after this approach has been well documented. In order to avoid subscapularis complications, Lafosse reported a technique for total shoulder arthroplasty that utilizes a trans-deltoid approach through the rotator interval that yielded satisfactory clinical outcomes. However, he also reported concerns about humeral head undersizing and inadequate osteophyte resection. We present an alternative subscapularis preserving technique that is performed through the deltopectoral interval and allows complete osteophyte excision and accurate humeral head sizing. This technique requires modified instrumentation and is facilitated by the use of an adaptable prosthesis with dual eccentricity. Case examples using this technique are presented.