Andrew J. Riff

Biomechanical Evaluation of Bioabsorbable versus Metallic Screws for Posterior Cruciate Ligament Inlay Graft Fixation: A Comparative Study

Background Although a tibial inlay technique for posterior cruciate ligament reconstruction is advantageous, metallic screw fixation of the bone block is required. This may pose problems for future surgery (eg, osteotomies, total knee replacement). Hypothesis There is no significant difference in the biomechanical integrity of bone block fixation using stainless steel versus bioabsorbable screw fixation of the tibial inlay graft in posterior cruciate ligament reconstruction. Study Design Controlled laboratory study. Methods Fourteen human cadaveric knees were randomized to receive either stainless steel or bioabsorbable screw fixation of a bone—patellar tendon—bone graft. Cyclic tensile testing of each construct was performed, followed by a load-to-failure test. Digital video digitization was used to optically determine tendon graft deformation. Results Cyclic creep deformation showed no significant difference between the 2 groups (P = .8). The failure load (stainless steel, 461 ± 231 N; bioabsorbable, 638 ± 492 N; P = .7) and linear stiffness (stainless steel, 116 ± 22 N/mm, bioabsorbable, 106 ± 44 N/mm; P = .6) also showed no significant difference between the 2 groups. Optically measured graft deformation was not significant for distal (P = .7) and midsubstance (P = .8) regions, while proximal deformation was significantly higher for bioabsorbable fixation (P = .02). All samples failed at the tibial insertion site with the tibial bone block fracturing at the screws. Conclusion Bioabsorbable screw fixation using a tibial inlay technique does not compromise the strength and stiffness characteristics afforded by metallic fixation. From a biomechanical perspective, bioabsorbable screws are a viable alternative to metal in the context of tibial inlay reconstruction. Clinical Relevance Use of bioabsorbable fixation can potentially eliminate future hardware problems after posterior cruciate ligament reconstruction using a tibial inlay technique.

Correlates With History of Injury in Youth and Adolescent Pitchers.

PURPOSE To determine the factors within pitcher demographic characteristics, pitching history, and pitch kinematics, including velocity, that correlate with a history of pitching-related injury. METHODS Demographic and kinematic data were collected on healthy youth and adolescent pitchers aged 9 to 22 years in preseason training during a single preseason using dual orthogonal high-speed video analysis. Pitchers who threw sidearm and those who had transitioned to another position were excluded. Players were asked whether they had ever had a pitching-related shoulder or elbow injury. Multivariate logistic regression analysis was performed on those variables that correlated with a history of injury. RESULTS Four hundred twenty pitchers were included, of whom 31% had a history of a pitching-related injury. Participant height (P = .009, R(2) = 0.023), pitching for more than 1 team (P = .019, R(2) = 0.018), and pitch velocity (P = .006, R(2) = 0.194) served as independent correlates of injury status. A model constructed with these 3 variables could correctly predict 77% of injury histories. Within our cohort, the presence of a 10-inch increase in height was associated with an increase in a history of injury by 20% and a 10-mph increase in velocity was associated with an increase in the likelihood of a history of injury by 12%. Playing for more than 1 team increased the likelihood of a history of injury by 22%. CONCLUSIONS Pitch velocity, pitcher height, and pitching for more than 1 team correlate with a history of shoulder and elbow injury. Current recommendations regarding breaking pitches may not prevent injury. Pitchers should be cautioned about pitching for more than 1 team. Taller pitchers and high-velocity pitchers may be at risk of injury.

Arthroscopic Technique for the Treatment of Pigmented Villonodular Synovitis of the Hip

Open synovectomy remains the treatment of choice for pigmented villonodular synovitis (PVNS) of the hip but has shown modest results compared with the treatment of other joints. Recent advances in hip arthroscopy permit a thorough evaluation of the joint surfaces, improved access, and decreased postoperative morbidity. We describe an arthroscopic synovectomy technique for PVNS of the hip. The use of additional arthroscopic portals and creation of a large capsulotomy enable successful visualization and extensive synovectomy of the entire synovial lining of the hip. The T-capsulotomy enables extensive soft-tissue retraction for complete exposure. The midanterior portal enables use of an arthroscopic grasper and shaver to directly access and excise the synovial lining of the peripheral compartment while avoiding damage to the medial and lateral retinacular vessels. Technical innovations in hip arthroscopy have enhanced visualization in the central and peripheral compartments, as well as instrument management and diagnostic evaluation of the capsule, therefore allowing enhanced management of PVNS of the hip.

Outcomes and Complications of Unicondylar Arthroplasty

Unicompartmental knee arthroplasty has experienced resurgence in popularity because of the lower morbidity of the procedure and the proposed benefits over total knee replacement in appropriately selected patients. Improved component designs and advanced surgical techniques have promoted excellent results. Expanded indications to include the very young and the elderly have yielded comparable clinical outcomes. Nonetheless, the success of unicompartmental replacement depends on proper surgical technique and patient selection. Distinct surgical considerations exist depending on whether the medial, lateral, or patellofemoral compartment is replaced. Long-term studies have shown that unicompartmental knee replacement is an alternative to total knee arthroplasty.

What Factors Influence the Biomechanical Properties of Allograft Tissue for ACL Reconstruction? A Systematic Review

BackgroundAllograft tissue is used in 22% to 42% of anterior cruciate ligament (ACL) reconstructions. Clinical outcomes have been inconsistent with allograft tissue, with some series reporting no differences in outcomes and others reporting increased risk of failure. There are numerous variations in processing and preparation that may influence the eventual performance of allograft tissue in ACL reconstruction. We sought to perform a systematic review to summarize the factors that affect the biomechanical properties of allograft tissue for use in ACL reconstruction. Many factors might impact the biomechanical properties of allograft tissue, and these should be understood when considering using allograft tissue or when reporting outcomes from allograft reconstruction.Questions/purposesWhat factors affect the biomechanical properties of allograft tissue used for ACL reconstruction?MethodsWe performed a systematic review to identify studies on factors that influence the biomechanical properties of allograft tissue through PubMed and SCOPUS databases. We included cadaveric and animal studies that reported on results of biomechanical testing, whereas studies on fixation, histologic evaluation, and clinical outcomes were excluded. There were 319 unique publications identified through the search with 48 identified as relevant to answering the study question. For each study, we recorded the type of tissue tested, parameters investigated, and the effects on biomechanical behavior, including load to failure and stiffness. Primary factors identified to influence allograft tissue properties were graft tissue type, sterilization methods (irradiation and chemical processing), graft preparation, donor parameters, and biologic adjuncts.ResultsLoad to failure and graft stiffness varied across different tissue types, with nonlooped tibialis grafts exhibiting the lowest values. Studies on low-dose irradiation showed variable effects, whereas high-dose irradiation consistently produced decreased load to failure and stiffness values. Various chemical sterilization measures were also associated with negative effects on biomechanical properties. Prolonged freezing decreased load to failure, ultimate stress, and ultimate strain. Up to eight freeze-thaw cycles did not lead to differences in biomechanical properties of cadaveric grafts. Regional differences were noted in patellar tendon grafts, with the central third showing the highest load to failure and stiffness. Graft diameter strongly contributed to load-to-failure measurements. Age older than 40 years, and especially older than 65 years, negatively impacted biomechanical properties, whereas gender had minimal effect on the properties of allograft tissue. Biologic adjuncts show potential for improving in vivo properties of allograft tissue.ConclusionsFuture clinical studies on allograft ACL reconstruction should investigate in vivo graft performance with standardized allograft processing and preparation methods that limit the negative effects on the biomechanical properties of tissue. Additionally, biologic adjuncts may improve the biomechanical properties of allograft tissue, although future preclinical and clinical studies are necessary to clarify the role of these treatments.Clinical RelevanceBased on the findings of this systematic review that emphasize biomechanical properties of ACL allografts, surgeons should favor the use of central third patellar tendon or looped soft tissue grafts, maximize graft cross-sectional area, and favor grafts from donors younger than 40 years of age while avoiding grafts subjected to radiation doses > 20 kGy, chemical processing, or greater than eight freeze-thaw cycles.

Operative treatment of FAI: open hip preservation surgery

Femoroacetabular Impingement (FAI) is characterized by abnormal contact of the hip joint. Many etiologies cause this painful condition, which leads to early osteoarthritis. While hip arthroscopy has become the most prevalent way to surgically correct a hip, some presentations of FAI require open surgical hip preservation techniques to fully address the pathology at hand. Certain head neck deformities may require open surgical hip dislocation utilizing a trochanteric slide osteotomy. A retroverted acetabulum may require an open periacetabular osteotomy to gain anteversion and eliminate impingement in the hip joint. Acetabular protrusio may require surgical hip dislocation with rim trimming and a possible valgus intertrochanter osteotomy. The sequelae of Legg-Calvé-Perthes disease causes complex abnormalities about the hip joint, which may require open surgery to address both the intra-articular pathology and the extra-articular pathology. Osteotomies of the proximal femur and acetabulum may all be necessary to restore a hip back to normal morphology. Chronic slipped capital femoral epiphysis (SCFE) may also require open surgical hip dislocations and complex intertrochanter osteotomies to recreate normal morphology.

Midterm results of osteochondral allograft transplantation to the humeral head

BACKGROUND This study evaluated clinical outcomes of osteochondral allograft (OCA) transplantation for humeral head osteochondral defects. We hypothesized that patients with isolated humeral head disease would achieve favorable results and that patients with bipolar disease would experience inferior outcomes. METHODS We identified patients who underwent humeral head OCA transplantation. Subjective questionnaire data were obtained preoperatively and at a minimum of 2 years postoperatively. Radiographs were evaluated for graft incorporation. Failure was defined by conversion to shoulder arthroplasty, American Shoulder and Elbow Surgeons score <50, or dissatisfaction with the surgical result. RESULTS Twenty patients (65% male) met inclusion criteria. Patients were an average age of 24.8 ± 8.1 years. Eleven patients underwent concomitant glenoid surgery (microfracture or meniscal allograft resurfacing). Follow-up was available for 18 patients (90%) at mean of 67 months. All grafts incorporated except 2. Four patients underwent shoulder arthroplasty at mean of 25 months postoperatively (all after pain pump chondrolysis). Eleven of the 20 patients were satisfied (all dissatisfied patients underwent glenoid surgery). Significant improvements (P < .001) were seen for the visual analog scale (from 6.1 to 1.5), Simple Shoulder Test (from 32 to 73), American Shoulder and Elbow Surgeons score (from 39 to 76), and the physical component of the 12-Item Short Form Survey (from 38 to 48). Pain pump patients who did not progress to arthroplasty experienced inferior satisfaction (40% vs. 87.5%, P = .04) and a trend toward inferior outcomes compared with the rest of the cohort. CONCLUSION OCA transplantation is a viable option for young patients with isolated humeral chondral injury. Patients with bipolar disease or a history of intra-articular pain pump have increased failure and decreased subjective outcomes.

Operative Treatment of Femoroacetabular Impingement

Abstract Femoroacetabular impingement is a common pathologic disorder of the hip that causes pain and has been implicated in the development of early osteoarthritis in young adults. This disorder includes 2 different subtypes: cam impingement and pincer impingement. When nonsurgical treatment methods fail, surgical options are indicated. These options have been increasingly investigated over recent years and show promising results. Several surgical techniques have been described, including surgical dislocation of the hip, mini-open procedures, hip arthroscopy, and periacetabular osteotomies. Nevertheless, the preferred mode of surgical management of femoroacetabular impingement remains a source of controversy. Only short-term and midterm outcome data are available regarding the efficacy of these surgical techniques. This review details 5 approaches for surgical management of femoroacetabular impingement: open surgical dislocation, a combined arthroscopic and open approach, hip arthroscopy, a mini-open anterior approach, and periacetabular osteotomy. It focuses specifically on surgical technique, outcomes, and their efficacy in treatment of femoroacetabular impingement.

Trends in Shoulder Stabilization Techniques Used in the United States Based on a Large Private-Payer Database:

Background: Arthroscopic stabilization is the most broadly used surgical procedure in the United States for management of recurrent shoulder instability. Latarjet coracoid transfer has been considered a salvage surgical procedure for failed arthroscopic repairs or cases of significant glenoid bone loss; however, with recent literature suggesting reduced risk of recurrent instability with Latarjet, several surgeons have advocated its broader utilization as a primary operation for treatment of shoulder instability. Purpose: To determine trends in shoulder stabilization techniques used in the United States. Study Design: Cross-sectional study. Methods: A retrospective analysis of a publicly available national insurance database was performed to identify shoulder stabilization procedures performed over 9 years (2007-2015). The following Current Procedural Terminology codes were searched: 29806 (arthroscopic stabilization), 23455 (open capsulolabral repair), 23466 (open capsular shift), 23462 (Latarjet coracoid transfer), and 23460 (open anterior capsulorrhaphy with other bone block augmentation). Outcomes of interest included (1) trends in the use of each technique throughout the study interval, (2) age and sex distributions of patients undergoing each technique, and (3) regional predilections for the use of each technique. Results: Arthroscopic stabilization was the most broadly used shoulder stabilization procedure in the database (87%), followed by open Bankart (7%), Latarjet (3.2%), open capsular shift (2.6%), and alternative bone block procedure (0.8%). Throughout the study period, the incidence of arthroscopic stabilization and Latarjet increased (8% and 15% per year, respectively); the incidence of open capsular shift remained relatively constant; and the incidence of open Bankart decreased (9% per year). Arthroscopic stabilization, open Bankart, and Latarjet each had similar sex-based distributions (roughly 70% male), while open capsular shift and alternative bone block were relatively more common in females (54% and 50% male, respectively). The incidence of arthroscopic stabilization and Latarjet were greatest in the South and lowest in the Northeast. Conclusion: Arthroscopic stabilization remains the most commonly utilized stabilization technique in the United States. The use of the Latarjet procedure is steadily increasing and now rivals open Bankart stabilization among the most commonly used open stabilization techniques.

Blastomyces Tenosynovitis of the Foot and Ankle: A Case Report and Review of the Literature

Deep fungal infection localized to the foot is not common, and when it occurs it often affects immunocompromised individuals. In this report, we describe the case of an adult diabetic patient who suffered with with Blastomycosis infection of the flexor digitorum longus and peroneal tendon sheaths. The condition was treated with systemic antifungal therapy and surgical debridement.