Joseph U. Barker

The importance of medial support in locked plating of proximal humerus fractures.

Objectives: The purpose of this study was to determine what factors influence the maintenance of fracture reduction after locked plating of proximal humerus fractures, and particularly the role of medial column support. Setting: University medical center. Intervention: Thirty-five patients who underwent locked plating for a proximal humerus fracture were followed up until healing. For the initial and final radiographs, 2 lines were drawn perpendicular to the shaft of the plate, one at the top of the plate and one at the top of the humeral head, and the distance between them was measured as an indicator of loss of reduction. Medial support was considered to be present if the medial cortex was anatomically reduced, if the proximal fragment was impacted laterally in the distal shaft fragment, or if an oblique locking screw was positioned inferomedially in the proximal humeral head fragment. Main Outcome Measurements: Multivariate linear regressions were performed to determine the effects that age, sex, fracture type, cement augmentation, and medial support had on loss of reduction. Results: The presence of medial support had a significant effect on the magnitude of subsequent reduction loss (P < 0.001). Age, sex, fracture type, or cement augmentation had no effect on maintenance of reduction. Eighteen patients were determined to have adequate mechanical medial support (+MS group), and the remaining 17 patients did not have medial support (-MS group). In the +MS group, the average loss of humeral head height was 1.2 mm, and 1 case of articular screw penetration occurred that required removal. In the −MS group (without an appropriately placed inferomedial oblique screw and either nonanatomic humeral head malreduction with lateral displacement of the shaft or medial comminution), loss of humeral height averaged 5.8 mm (P < 0.001). There were 5 cases in this group in which screw penetration of the articular surface occurred (P = 0.02), 2 of which required reoperation for removal. All fractures in both groups healed without delay, and none required revision to arthroplasty. Conclusions: Achieving mechanical support of the inferomedial region of the proximal humerus seems to be important for maintaining fracture reduction. Locked plates in general do not appear to be a panacea for these fractures and are unable to support the humeral head alone from a lateral tension-band position. However, there are several factors that are in the surgeons control that may improve the mechanical environment. Achieving an anatomic or slightly impacted stable reduction, as well as meticulously placing a superiorly directed oblique locked screw in the inferomedial region of the proximal fragment, may achieve more stable medial column support and allow for better maintenance of reduction.

The Role of Growth Factors in Cartilage Repair

BackgroundFull-thickness chondral defects and early osteoarthritis continue to present major challenges for the patient and the orthopaedic surgeon as a result of the limited healing potential of articular cartilage. The use of bioactive growth factors is under consideration as a potential therapy to enhance healing of chondral injuries and modify the arthritic disease process.Questions/purposesWe reviewed the role of growth factors in articular cartilage repair and identified specific growth factors and combinations of growth factors that have the capacity to improve cartilage regeneration. Additionally, we discuss the potential use of platelet-rich plasma, autologous-conditioned serum, and bone marrow concentrate preparations as methods of combined growth factor delivery.MethodsA PubMed search was performed using key words cartilage or chondrocyte alone and in combination with growth factor. The search was open for original manuscripts and review papers and open for all dates. From these searches we selected manuscripts investigating the effects of growth factors on extracellular matrix synthesis and excluded those investigating molecular mechanisms of action.ResultsBy modulating the local microenvironment, the anabolic and anticatabolic effects of a variety of growth factors have demonstrated potential in both in vitro and animal studies of cartilage injury and repair. Members of the transforming growth factor-β superfamily, fibroblast growth factor family, insulin-like growth factor-I, and platelet-derived growth factor have all been investigated as possible treatment augments in the management of chondral injuries and early arthritis.ConclusionsThe application of growth factors in the treatment of local cartilage defects as well as osteoarthritis appears promising; however, further research is needed at both the basic science and clinical levels before routine application.

Management of proximal humeral fractures based on current literature

Proximal humeral fractures are the second most common upper-extremity fracture and the third most common fracture, after hip fractures and distal radial fractures, in patients who are older than sixty-five years of age1. Although the overwhelming majority of proximal humeral fractures are either nondisplaced or minimally displaced and can be treated with sling immobilization and physical therapy, approximately 20% of displaced proximal humeral fractures may benefit from operative treatment. Many surgical techniques have been described, but no single approach is considered to be the standard of care. Surgeons who treat proximal humeral fractures should be able to identify the fracture pattern and select an appropriate treatment on the basis of this pattern and the underlying quality of the bone. Orthopaedic surgeons should have experience with a broad range of techniques, including transosseous suture fixation, closed reduction and percutaneous fixation, open reduction and internal fixation with conventional and locked-plate fixation, and hemiarthroplasty. In the future, locked-plate technology and the use of osteobiologics may play an increasingly important role in the treatment of displaced proximal humeral fractures, facilitating preservation of the humeral head in appropriately selected patients. The goals of this article are to enable the reader to: (1) become familiar with the recent literature on the classification of and treatment options for proximal humeral fractures, and (2) better identify fracture characteristics and devise an appropriate treatment plan. ### Transosseous Suture Fixation #### Surgical Technique Park et al.2 described different operative approaches for each fracture pattern described by Neer 3. For two-part greater tuberosity fractures, an anterosuperior approach along the Langer lines extending from the lateral aspect of the acromion toward the lateral tip of the coracoid is used. The split occurs in the anterolateral raphe and allows exposure of the displaced greater tuberosity fracture. When a surgical neck fracture exists, Park et al.2 …

Effect of graft selection on the incidence of postoperative infection in anterior cruciate ligament reconstruction.

Background Knee joint infection is a potentially devastating complication of anterior cruciate ligament (ACL) reconstruction. There is a theoretical increased risk of infection with the use of allograft material. Hypothesis An allograft ACL reconstruction predisposes patients to a higher risk of bacterial infection. Study Design Cohort Study; Level of evidence, 3. Methods All primary ACL reconstructions performed at our institution between January 2002 and December 2006 were reviewed; 3126 total procedures were identified. A retrospective medical record review was performed to determine the incidence of infection, offending organism, time after surgery until presentation, infection treatment, and graft salvage as an outcome of graft choice. Results Of the 3126 ACL reconstructions, 1777 autografts and 1349 allografts were performed. Eighteen infections were identified (0.58%). Infections occurred in 6 of the 1349 allografts (0.44%), 7 of the 1430 bone-patellar tendon-bone (BPTB) autografts (0.49%), and 5 of the 347 hamstring autografts (1.44%). Five grafts were removed because of graft incompetence or loosening: 3 hamstring tendon, 1 BPTB, and 1 allograft. The most common organism isolated was Staphylococcus aureus. Hamstring tendon autograft had an increased incidence of infection compared with both BPTB autograft and allograft (P < .05), with a trend toward a more common need for graft removal (P = .09). Allograft reconstructions were equally likely to have graft salvage as autograft reconstructions. Conclusion Hamstring tendon autografts have a higher incidence of infection than BPTB autografts or allografts. The use of allograft material in ACL reconstructions does not increase the risk of infection or the need for graft removal with infection.

Anatomy and Dimensions of the Gluteus Medius Tendon Insertion

PURPOSE The purpose of this study was to determine the area, dimensions, and orientation of the gluteus medius footprint to provide an improved understanding of its insertional anatomy. METHODS Eight fresh-frozen cadaveric hips were dissected, leaving only the most distal gluteus medius tendon attached to the greater trochanter. The tendon insertion footprint and proximal femur were digitized and mapped by use of 3-dimensional computer navigation software. The area, location, and dimensions of the tendon insertion were determined. RESULTS The gluteus medius tendon has 2 distinct insertion sites on the greater trochanter, the lateral facet and the superoposterior facet. The mean areas of insertion onto the lateral and superoposterior facets were 438.0 mm2 (SD, 57.7 mm2) and 196.5 mm2 (SD, 48.4 mm2), respectively. The lateral facet footprint had a mean longitudinal dimension of 34.8 mm (SD, 4.3 mm), was angled at a mean of 36.8 degrees (SD, 6.7 degrees ) relative to the long axis of the femur, and had a mean minimum width of 11.2 mm (SD, 1.8 mm). The superoposterior facets shape approximated that of a circle, with a mean diameter of 17 mm (SD, 2.0 mm). CONCLUSIONS The gluteus medius tendon has 2 distinct and consistent insertion sites onto the greater trochanter. This information will provide surgeons with a better understanding of the footprint anatomy when evaluating gluteus medius tendon tears. CLINICAL RELEVANCE Gluteus medius tendon tears can be a source of significant pain and morbidity. This study describes the anatomic morphology of this tendon insertion, which should aid in its repair when necessary.

The arthroscopic management of partial-thickness rotator cuff tears: A systematic review of the literature

PURPOSE There is currently limited information available in the orthopaedic surgery literature regarding the appropriate management of symptomatic partial-thickness rotator cuff tears. METHODS A systematic search was performed in PubMed, EMBASE, CINAHL (Cumulative Index to Nursing and Allied Health Literature), and the Cochrane Central Register of Controlled Trials of all published literature pertaining to the arthroscopic management of partial-thickness rotator cuff tears. Inclusion criteria were all studies that reported clinical outcomes after arthroscopic treatment of both articular-sided and bursal-sided lesions using a validated outcome scoring system and a minimum of 12 months of follow-up. Data abstracted from the selected studies included tear type and location (articular v bursal sided), treatment approach, postoperative rehabilitation protocol, outcome scores, patient satisfaction, and postoperative imaging results. RESULTS Sixteen studies met the inclusion criteria and were included for the final analysis. Seven of the studies treated partial-thickness rotator cuff tears with debridement with or without an associated subacromial decompression, 3 performed a takedown and repair, 5 used a transtendon repair technique, and 1 used a transosseous repair method. Among the 16 studies reviewed, excellent postoperative outcomes were reported in 28.7% to 93% of patients treated. In all 12 studies with available preoperative baseline data, treatment resulted in significant improvement in shoulder symptoms and function. For high-grade lesions, the data support arthroscopic takedown and repair, transtendon repairs, and transosseous repairs, with all 3 techniques providing a high percentage of excellent results. Debridement of partial-thickness tears of less than 50% of the tendons thickness with or without a concomitant acromioplasty also results in good to excellent surgical outcomes; however, a 6.5% to 34.6% incidence of progression to full-thickness tears is present. CONCLUSIONS This systematic review of 16 clinical studies showed that significant variation is present in the results obtained after the arthroscopic management of partial-thickness rotator cuff tears. What can be supported by the available data is that tears that involve less than 50% of the tendon can be treated with good results by debridement of the tendon with or without a formal acromioplasty, although subsequent tear progression may occur. When the tear is greater than 50%, surgical intervention focusing on repair has been successful. There is no evidence to suggest a differential in outcome for tear completion and repair versus transtendon repair of these lesions because both methods have been shown to result in favorable outcomes. LEVEL OF EVIDENCE Level IV, systematic review of Level IV studies.

Can Anatomic Femoral Tunnel Placement Be Achieved Using a Transtibial Technique for Hamstring Anterior Cruciate Ligament Reconstruction

Background: Recent studies have emphasized the importance of anatomic tunnel placement during anterior cruciate ligament (ACL) reconstruction in an effort to restore normal knee kinematics and stability. Secondary to the constraints imposed by a coupled drilling technique, the ability to achieve an anatomic femoral tunnel during transtibial hamstring ACL reconstruction may be limited. Hypothesis: The size limitations imposed by the small-diameter tibial tunnel used in hamstring ACL reconstruction would preclude the ability to place an anatomic femoral tunnel. Study Design: Descriptive laboratory study. Methods: In a descriptive laboratory study, fresh-frozen human cadaveric knees fixed at 90° of flexion were dissected to expose the centers of the native femoral and tibial ACL insertions. The geometry and location of each insertion were evaluated. Using a standardized starting point, tibial tunnels were drilled to the center of the tibial insertion using an 8-mm reamer. Next, a 6-mm over-the-top guide was used to position as close as possible to the anatomic femoral ACL insertion on the lateral wall, and femoral tunnels were drilled with the 8-mm reamer. For each tunnel, the location, geometry, and percentage overlap with the native insertion site were evaluated using a 3-dimensional laser scanner. Results: The reamed tibial tunnel was central within the insertion site, occupying 40.4% ± 2.0% of the native tibial insertion. Transtibial drilling resulted in femoral tunnels that were superior and posterior compared with the native femoral insertion. Thefemoral tunnel had a mean ± SD overlap of 30.0% ± 12.6% with the femoral insertion, with the center of the tunnel 7.6± 0.5 mm from the center of the native ACL femoral insertion. Conclusion: Based on our data using our specific starting point, during hamstring ACL reconstructions, the constraints imposed by a coupled drilling technique result in nonanatomic femoral tunnels that are superior and posterior to the native femoral insertion. Clinical Relevance: Anatomic femoral tunnel placement during hamstring ACL reconstructions may not be possible using a coupled, transtibial drilling approach.

Innovations in the Management of Displaced Proximal Humerus Fractures

Abstract The management of displaced proximal humerus fractures has evolved toward humeral head preservation, with treatment decisions based on careful assessment of vascular status, bone quality, fracture pattern, degree of displacement, and patient age and activity level. The AO/ASIF fracture classification is helpful in guiding treatment and in stratifying the risk for associated disruption of the humeral head blood supply. Nonsurgical treatment consists of sling immobilization. For patients requiring surgery, options include closed reduction and percutaneous fixation; transosseous suture fixation; open reduction and internal fixation, with either conventional or locking plate fixation; bone graft; and hemiarthroplasty. Proximal humerus fractures must be evaluated on an individual basis, with treatment tailored according to patient and fracture characteristics.

The evaluation and management of failed distal clavicle excision.

Excision of the distal clavicle (DCE) is a commonly carried out surgical procedure used in the management of acromioclavicular joint pathology. Although successful outcomes after both open and arthroscopic distal clavicle excision occur in a high percentage of patients, treatment failures have been reported, creating a difficult clinical scenario for the treating orthopedic surgeon. The most common mode of failure after DCE is persistent pain and potential etiologies include under-resection, over-resection leading to joint instability, postoperative stiffness, heterotopic ossification, untreated concomitant shoulder pathology, and postoperative infection. Less common causes of failure include distal clavicle fracture, reossification or fusion across the acromioclavicular joint, suprascapular neuropathy, and psychiatric illness. Persistent symptoms and disability after distal clavicle excision require a careful assessment of these potential causes of treatment failure and the formulation of a treatment plan, which may include conservative care, revision surgery, or coracoclavicular ligament reconstruction. Although careful patient selection, preoperative planning, proper surgical technique, and appropriate rehabilitation during the index procedure can minimize the likelihood of poor outcome, this paper reviews the work-up and management of cases of failed distal clavicle excision.

Augmentation Strategies following the Microfracture Technique for Repair of Focal Chondral Defects.

The operative management of focal chondral lesions continues to be problematic for the treating orthopedic surgeon secondary to the limited regenerative capacity of articular cartilage. Although many treatment options are currently available, none fulfills the criteria for an ideal repair solution, including a hyaline repair tissue that completely fills the defect and integrates well with the surrounding normal cartilage. The microfracture technique is an often-utilized, first-line treatment modality for chondral lesions within the knee, resulting in the formation of a fibrocartilaginous repair tissue with inferior biochemical and biomechanical properties compared to normal hyaline cartilage. Although symptomatic improvement has been shown in the short term, concerns about the durability and longevity of the fibrocartilaginous repair have been raised. In response, a number of strategies and techniques for augmentation of the first-generation microfracture procedure have been introduced in an effort to improve repair tissue characteristics and reduce long-term deterioration. Recent experimental approaches utilize modern tissue-engineering technologies including local supplementation of chondrogenic growth factors, hyaluronic acid, or cytokine modulation. Other second-generation microfracture-based techniques use different types of scaffold-guided in situ chondroinduction. The current article presents a comprehensive overview of both the experimental and early clinical results of these developing microfracture augmentation techniques.