Nathan W. Skelley

What Is the Role of Arthroscopic Debridement for Glenohumeral Arthritis? A Critical Examination of the Literature

PURPOSE To critically examine the outcomes of arthroscopic debridement for glenohumeral arthritis and to perform an evidence-based synthesis of the available literature. METHODS A systematic review of the literature was performed by a search of electronic databases. Two reviewers independently assessed the methodologic quality and extracted relevant data from each included study. When outcomes data were similar between studies, data were pooled for the purposes of generating summary outcomes through the use of frequency-weighted values. RESULTS Five studies were included after fulfilling all inclusion and exclusion criteria. At a frequency-weighted mean follow-up of 34.8 months, 212 patients (range, 19 to 71 patients) with a frequency-weighted mean age of 49.2 years were available for follow-up evaluation. In general, patients had significant improvement in motion and functional outcomes. Thirteen percent of patients underwent conversion to a shoulder arthroplasty. The influence of specific patient demographics, degree of glenohumeral stiffness, and arthritis severity on functional outcome and treatment failure could not be determined. CONCLUSIONS This systematic review shows that arthroscopic debridement for glenohumeral arthritis lacks high-quality evidence to support its routine use. Level IV-type evidence would suggest improvement in pain relief and patient satisfaction in the short-term. Future studies should comprehensively define patient characteristics, trend results over time, and attempt to find associations between patient variables and outcome. LEVEL OF EVIDENCE Level IV, systematic review of Level IV studies.

Arthroscopic Debridement and Capsular Release for the Treatment of Shoulder Osteoarthritis

PURPOSE The purpose of this study was to evaluate patients who underwent isolated arthroscopic debridement and capsular release without any other procedures for primary glenohumeral osteoarthritis to determine clinical and functional outcomes and time until conversion to shoulder arthroplasty. METHODS We performed a retrospective review of 33 patients who underwent arthroscopic debridement and capsular release for shoulder osteoarthritis at our institution between 2006 and 2011. All procedures were performed by a single surgeon (K.Y.). Patients were evaluated for intraoperative arthritis grade, preoperative and postoperative range or motion, American Shoulder and Elbow Surgeons (ASES) score, pain score self-assessments, radiographic evaluation, and conversion to total shoulder arthroplasty. Clinical follow-up was on average 40.3 weeks postoperatively and telephone interview follow-up was performed at a minimum of 2 years postoperatively in all patients. RESULTS There was an initial improvement in range of motion and pain scores; however, patients in our study returned to preoperative levels approximately 3.8 months after debridement and capsular release. Twenty patients (60.6%) reported that they were not satisfied with the outcome of the procedure. Total shoulder arthroplasty was undertaken in 14 (42.4%) patients an average of 8.8 months after arthroscopy. Among the 19 (57.6%) patients who did not go on to have total shoulder arthroplasty, ASES scores (42.2 to 50.8; P = .41) and visual analog scale pain scores (7.8 to 7.4; P = .59) were similar preoperatively and at final telephone follow-up. CONCLUSIONS Isolated arthroscopic debridement and capsular release without any other procedures were associated with only temporary pain relief and improvement in motion. Although there are limited nonarthroplasty surgical options available for glenohumeral arthritis, isolated arthroscopic debridement and capsular release may not provide substantial benefit to justify its use in most patients. LEVEL OF EVIDENCE Level IV, therapeutic case series.

Inter- and Intraobserver Reliability in the MRI Measurement of the Tibial Tubercle–Trochlear Groove Distance and Trochlea Dysplasia

Background: The tibial tubercle–trochlear groove (TT-TG) distance and trochlear structure have become important radiographic measurements in the evaluation and management of patients with patellar instability. Many orthopaedic surgeons, however, do not have access to musculoskeletal radiologists and therefore must make such measurements independently. Purpose: To determine the intra- and interobserver reliability in the measurement of the TT-TG distance and the determination of the trochlear dysplasia index (TDI) between musculoskeletal radiologists and orthopaedic surgeons. Study Design: Cohort study (diagnosis); Level of evidence, 3. Methods: Magnetic resonance imaging (MRI) was obtained from 63 patients with the clinical diagnosis of patellar instability (instability group) and from 53 patients without patellar instability (control group). Three radiologists and 2 orthopaedic surgeons blinded to the group assignment independently measured the TT-TG distance and determined the TDI. Each MRI was measured on 2 occasions separated by at least 1 week. Intraclass correlation coefficients (ICCs) were calculated to determine the intra- and interobserver reliability. Results: The instability and control groups were similarly stratified across age, sex, affected knee, athletic level, and body mass index. The mean TT-TG distances were 18.2 ± 5.6 mm and 13.7 ± 5.6 mm for the instability and control groups, respectively (P < .001). The mean TDI for the instability and control groups was 2.1 ± 1.6 mm and 4.6 ± 1.3 mm, respectively (P < .001). There was almost perfect intraobserver reliability for both the TT-TG distance and TDI measurements between the 2 time points for all observers (ICCs: ≥0.86 [TT-TG distance], ≥0.88 [TDI]). The interobserver reliability was also almost perfect between the orthopaedic surgeons and radiologists for both the TT-TG distance (ICC, 0.85 [95% CI, 0.82-0.88]) and TDI (ICC, 0.84 [95% CI, 0.79-0.88]). Conclusion: The results of this study suggest that the intra- and interobserver reliability in the MRI measurement of the TT-TG distance and TDI is high for both orthopaedic surgeons and musculoskeletal radiologists. In addition, the TT-TG distance may be lower than previously thought in patients with patellar instability.

In-game Management of Common Joint Dislocations

Context: Sideline management of sports-related joint dislocations often places the treating medical professional in a challenging position. These injuries frequently require prompt evaluation, diagnosis, reduction, and postreduction management before they can be evaluated at a medical facility. Our objective is to review the mechanism, evaluation, reduction, and postreduction management of sports-related dislocations to the shoulder, elbow, finger, knee, patella, and ankle joints. Evidence Acquisition: A literature review was performed using the PubMed database to evaluate previous and current publications focused on joint dislocations. This review focused on articles published between 1980 and 2013. Study Design: Clinical review. Level of Evidence: Level 4. Results: The clinician should weigh the benefits and risks of on-field reduction based on their knowledge of the injury and the presence of associated injuries. Conclusion: When properly evaluated and diagnosed, most sports-related dislocations can be reduced and initially managed at the game.

Differences in the Microstructural Properties of the Anteromedial and Posterolateral Bundles of the Anterior Cruciate Ligament

Background: Tissue properties of the anteromedial (AM) and posterolateral (PL) bundles of the anterior cruciate ligament (ACL) have not been previously characterized with real-time dynamic testing. The current study used a novel polarized light technique to measure the material and microstructural properties of the ACL. Hypothesis: The AM and PL bundles of the ACL have similar material and microstructural properties. Study Design: Controlled laboratory study. Methods: The AM and PL bundles were isolated from 16 human cadaveric ACLs (11 male, 5 female; average age, 41 years [range, 24-53 years]). Three samples from each bundle were loaded in uniaxial tension, and a custom-built polarized light imaging camera was used to quantify collagen fiber alignment in real time. A bilinear curve fit was applied to the stress-strain data of a quasistatic ramp-to-failure to quantify the moduli in the toe and linear regions. Fiber alignment was quantified at zero strain, the transition point of the bilinear fit, and in the linear portion of the stress-strain curve by computing the degree of linear polarization (DoLP) and angle of polarization (AoP), which are measures of the strength and direction of collagen alignment, respectively. Data were compared using t tests. Results: The AM bundle exhibited significantly larger toe-region (AM 7.2 MPa vs PL 4.2 MPa; P < .001) and linear-region moduli (AM 27.0 MPa vs PL 16.1 MPa; P = .017) compared with the PL bundle. Average DoLP values were similar at low strain but were significantly larger (ie, more uniform alignment) for the AM bundle in the linear region of the stress-strain curve (AM 0.22 vs PL 0.19; P = .036) compared with the PL bundle. The standard deviation AoP values was larger for the PL bundle at both transition (P = .041) and linear-region strain (P = .014), indicating more disperse orientation. Conclusion: Material and microstructural properties of the AM and PL bundles of the ACL differ during loading. The AM bundle possessed higher tissue modulus and failure stress, as well as more uniform fiber alignment under load. Clinical Relevance: These insights into native ligament microstructure can be used to assess graft options for ACL reconstruction and optimize surgical reconstruction techniques.

Regional Variation in the Mechanical and Microstructural Properties of the Human Anterior Cruciate Ligament

Background: The anteromedial (AM) bundle of the anterior cruciate ligament (ACL) has a higher modulus and failure stress than does the posterolateral (PL) bundle. However, it is unknown how these properties vary within each bundle. Purpose: To quantify mechanical and microstructural properties of samples within ACL bundles to elucidate any regional variation across the ligament. We hypothesized that there are no differences within each bundle in contrast to cross-bundle variation. Study Design: Descriptive laboratory study. Methods: Sixteen human ACLs were dissected into AM and PL bundles. Three samples were taken from each bundle in an ordered sequence from AM (region 1 AM bundle) to PL (region 6 PL bundle). Each sample was tested in uniaxial tension, using quantitative polarized light imaging (QPLI) to quantify collagen fiber alignment. After preconditioning, samples were subjected to a stress-relaxation (SR) test followed by quasistatic ramp-to-failure (RF). Peak and equilibrium stress values were computed from the SR test and modulus quantified in the toe- and linear-regions of the RF. QPLI values describing collagen orientation (angle of polarization [AoP]) and strength of alignment (degree of linear polarization [DoLP]) were computed for the SR test and at points corresponding to the zero, transition point, and linear region of the RF. Results: Toe- and linear-region modulus values decreased from region 1 to 6. Slopes of regression lines increased for the average DoLP during RF, with significance at higher strains. The standard deviation of AoP values decreased during RF, indicating tighter distribution of orientation angles, with significant correlations at all points of the RF. During SR, stress values uniformly decreased but did not show significant linear regression by region. DoLP and AoP values changed slightly during SR and demonstrated significant linear variation by region at both peak and equilibrium points. Conclusion: Most microstructural and material properties evaluated in this study appear to follow a linear gradient across the ACL, rather than varying by bundle. Clinical Relevance: This AM-to-PL variation provides a more accurate description of functional tissue anatomy and can be used to assess and guide techniques of ACL reconstruction.

Microstructural and Mechanical Properties of the Posterior Cruciate Ligament: A Comparison of the Anterolateral and Posteromedial Bundles

BACKGROUND The microstructural organization (collagen fiber alignment) of the posterior cruciate ligament (PCL), which likely corresponds with its functional properties, has only been described qualitatively in the literature, to our knowledge. The goal of this study was to quantify the tensile mechanical and microstructural properties of the PCL and compare these qualities between the anterolateral and posteromedial bundles. METHODS Twenty-two knee specimens from 13 donors (8 male and 5 female; mean age [and standard deviation] at the time of death, 43.0 ± 4.1 years; mean body mass index, 30.0 ± 6.7 kg/m2) were dissected to isolate the PCL, and each bundle was split into 3 regions. Mechanical testing of each regional sample consisted of preconditioning followed by a ramp-and-hold stress-relaxation test and a quasi-static ramp-to-failure test. Microstructural analysis was performed with use of a high-resolution, division-of-focal-plane polarization camera to evaluate the average direction of collagen orientation and the degree to which the collagen fibers were aligned in that direction. Results were compared between the anterolateral and posteromedial bundles and across the regions of each bundle. RESULTS The anterolateral and posteromedial bundles demonstrated largely equivalent mechanical and microstructural properties. Elastic moduli in the toe and linear regions were not different; however, the posteromedial bundle did show significantly more stress relaxation (p = 0.004). There were also few differences in microstructural properties between bundles, which again were seen only in stress relaxation. Comparing regions within each bundle, several mechanical and microstructural parameters showed significant relationships across the posteromedial bundle, following a gradient of decreasing strength and alignment from anterior to posterior. CONCLUSIONS The PCL has relatively homogenous microstructural and mechanical properties, with few differences between the anterolateral and posteromedial bundles. This finding suggests that distinct functions of the PCL bundles result primarily from size and anatomical location rather than from differences in these properties. CLINICAL RELEVANCE These properties of the PCL can be used to assess the utility of graft choices and operative techniques for PCL reconstruction and may partly explain limited differences in the outcomes of single-bundle compared with double-bundle reconstruction techniques for the PCL.

Microstructural properties of the anterior cruciate ligament

The anterior cruciate ligament (ACL) of the knee is one of the most commonly injured structures in musculoskeletal medicine. Although the ligament is widely researched and studied for its macroscopic biomechanical role in knee stability, surprisingly few studies have analyzed the microscopic material properties of this important ligament. Several recent studies, however, have evaluated the microstructural and fiber alignment properties of the ACL. The anteromedial (AM) region of the ACL has a different cellular composition and exhibits greater fiber alignment and failure strength compared to the posterolateral (PL) regions. Furthermore, these properties vary in a linear fashion across the ligament moving from anterior to posterior, rather than just differing in discrete anatomical bundles. This information provides a greater understanding of the native properties of the human ACL and serves as a guide for surgical techniques.

Prevention of Labral and Rotator Cuff Injuries in the Overhead Athlete

Overhead athletes place enormous demands on the shoulder and as a consequence are prone to injury. Labral tears and rotator cuff tears are potential problems seen with repetitive overhead activities. These injuries may be preventable if proper attention is given to early identification and treatment of abnormalities in the kinetic chain. To properly evaluate and treat these conditions, clinicians must understand the kinetic chain, the pathomechanics of labral and rotator cuff injury, and conditions that predispose the athlete to injury such as scapular dyskinesis and glenohumeral internal rotation deficit.