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Purpose: To quantify the effect of different size combinations of Hill-Sachs defects and bony Bankart defects on shoulder instability across a broad range of motion.Methods: A computer-based finite element approach was used to model an intact glenohumeral joint. Defects were created for the glenoid with respect to its width (12.5%, 25%, 37.5%, and 50%). The defect sizes chosen for the humeral head were 6%, 19%, 31%, and 44% of the diameter. Simulations were analyzed using quasi-static analysis with displacement control under 50 N of medial compression. Distance to dislocation (DTD) was the primary outcome.Results: Every progressive bony Bankart defect lowered the value of DTD (P < .0001). These DTD values of individual glenoid defects were the same for every abduction and rotation angle. This may be an artifact due to the glenoid's spherical-shape assumption, which was necessary for the sample-specific model and is not a completely accurate representation of specimen-specific geometry. The largest glenoid defect size had a DTD value of 0 mm, which signifies no contact between surfaces. At 90° of abduction, Hill-Sachs defect sizes 19%, 31% (P < .0001), and 44% (P < .0001) further reduced DTD values gradually after 30° of external rotation, 10° of external rotation, and 20° of internal rotation, respectively. This signifies loss of contact between articulating surfaces, resulting in reduced motion. However, at a 45° abduction angle, the loss of contact only occurred for humeral head defect sizes 31% and 44%.Conclusions: This model shows that increasing shoulder instability is predicted by increasing humeral head and glenoid defect sizes for a broad envelope of motion. The size of glenoid defect can be used to determine the baseline stability. An additional humeral head defect can further reduce the stability when the arm is in external rotation because of loss of contact.Clinical Relevance: The data from this study will be helpful in establishing thresholds for performing bony reconstructions. [ABSTRACT FROM AUTHOR]

Purpose The goal of this systematic review was to present the current best evidence for clinical outcomes of osteochondral autograft transplantation to elucidate the efficacy of this procedure. Methods PubMed, CINAHL, and the Cochrane Central Register of Controlled Trials were searched (key terms “knee,” “osteochondral autograft transfer,” or “mosaicplasty”) to identify relevant literature between 1950 and 2013 in the English language. This evaluation included studies in pediatric and adult patients with grade 3 or 4 articular cartilage injuries; the studies had a minimum of 25 patients and at least 12 months of follow-up and compared osteochondral autograft transfers/mosiacplasty with another treatment modality. Articles were limited to full-text randomized controlled trials or cohort studies. Main outcomes studied were patient-reported and functional outcome, with secondary outcomes including effect of lesion size, return to sport and sport function, radiographic outcomes, and reoperation rates. Results There were a total of 9 studies with 607 patients studied in this systematic review. When osteochondral autologous transfer/mosaicplasty (OATM) was compared with microfracture (MF), patients with OATM had better clinical results, with a higher rate of return to sport and maintenance of their sports function from before surgery. Meanwhile, patients who underwent MF trended toward more reoperations, with deterioration around 4 years after surgery. When compared with autologous chondrocyte implantation (ACI), clinical outcome improvement was not conclusive; however, at 10-year follow-up, a greater failure rate was found to be present in the OATM group. Conclusions Current evidence shows improved clinical outcomes with OATM when compared with preoperative conditions. These patients were able to return to sport as early as 6 months after the procedure. It could be suggested from the data that OATM procedures might be more appropriate for lesions that are smaller than 2 cm 2 with the known risk of failure between 2 and 4 years. Further high-quality prospective studies into the management of these articular cartilage injuries are necessary to provide a better framework within which to target intervention. Level of Evidence Level II, systematic review of Level I and II studies. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to perform a systematic review of the literature to compare outcomes of revision anterior stabilization surgeries based on technique. This study also sought to compare the impact of bone defects on outcomes. Methods: A systematic review of the electronic databases PubMed, Cochrane Central Register of Controlled Trials, and Scopus was performed in July 2012 and March 2013. Of 345 articles identified in the search, 17 studies with Level I to IV Evidence satisfied the inclusion criteria and were analyzed according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Recurrent instability was defined as redislocation, resubluxation, or a positive apprehensive test after revision surgery. Procedures were categorized as arthroscopic Bankart repair, open Bankart repair, Bristow-Latarjet procedure, and other open procedures. Results: In total, 388 shoulders were studied. Male patients comprised 74.1% of patients, 66.7% of cases involved the dominant shoulder, the mean age was 28.2 years, and the mean follow-up period was 44.2 months. The surgical procedures classified as “other open procedures” had the highest rate of recurrent instability (42.7%), followed by arthroscopic Bankart repair (14.7%), the Bristow-Latarjet procedure (14.3%), and open Bankart repair (5.5%). Inconsistent reporting of bone defects precluded drawing significant conclusions. Conclusions: A number of different procedures are used to address recurrent instability after a primary operation for anterior shoulder instability has failed. There is significant variability in the rate of recurrent instability after revision anterior shoulder stabilization surgery. Level of Evidence: Level IV, systematic review of Level I to IV studies. [Copyright &y& Elsevier]

Purpose: The purpose of this study was to evaluate the effect of graft size on patient-reported outcomes and revision risk after anterior cruciate ligament (ACL) reconstruction. Methods: A retrospective chart review of prospectively collected cohort data was performed, and 263 of 320 consecutive patients (82.2%) undergoing primary ACL reconstruction with hamstring autograft were evaluated. We recorded graft size; femoral tunnel drilling technique; patient age, sex, and body mass index at the time of ACL reconstruction; Knee Injury and Osteoarthritis Outcome Score (KOOS) and International Knee Documentation Committee score preoperatively and at 2 years postoperatively; and whether each patient underwent revision ACL reconstruction during the 2-year follow-up period. Revision was used as a marker for graft failure. The relation between graft size and patient-reported outcomes was determined by multiple linear regression. The relation between graft size and risk of revision was determined by dichotomizing graft size at 8 mm and stratifying by age. Results: After we controlled for age, sex, operative side, surgeon, body mass index, graft choice, and femoral tunnel drilling technique, a 1-mm increase in graft size was noted to correlate with a 3.3-point increase in the KOOS pain subscale (P = .003), a 2.0-point increase in the KOOS activities of daily living subscale (P = .034), a 5.2-point increase in the KOOS sport/recreation function subscale (P = .004), and a 3.4-point increase in the subjective International Knee Documentation Committee score (P = .026). Revision was required in 0 of 64 patients (0.0%) with grafts greater than 8 mm in diameter and 14 of 199 patients (7.0%) with grafts 8 mm in diameter or smaller (P = .037). Among patients aged 18 years or younger, revision was required in 0 of 14 patients (0.0%) with grafts greater than 8 mm in diameter and 13 of 71 patients (18.3%) with grafts 8 mm in diameter or smaller. Conclusions: Smaller hamstring autograft size is a predictor of poorer KOOS sport/recreation function 2 years after primary ACL reconstruction. A larger sample size is required to confirm the relation between graft size and risk of revision ACL reconstruction. Level of Evidence: Level III, retrospective comparative study. [Copyright &y& Elsevier]

Background: Various methods of bony stabilization, including modifications of Bristow and Latarjet procedures, are considered gold-standard treatment for recurrent anterior shoulder instability but are associated with unique complications and risk of reoperation. The purpose of this study was to identify the prevalence of these complications. We hypothesized that the Bristow-Latarjet procedure would be a successful technique for treatment of shoulder instability but associated with a risk of recurrent postoperative instability, reoperation, and other complications. Methods: A systematic review of multiple medical databases included studies reporting outcomes with complication and reoperation rates following original or modified versions of the Bristow or Latarjet shoulder stabilization surgeries. Results: Forty-five studies were analyzed (1,904 shoulders) (all Level IV evidence). Most subjects were male (82%). The dominant shoulder was the operative shoulder in 64% of cases. Mean subject age was 25.8 years. Mean clinical follow-up was 6.8 years. Ninety percent of surgeries were done open; 9.3% were all-arthroscopic. Total complication rate was 30%. Recurrent anterior dislocation and subluxation rates were 2.9% and 5.8%, respectively. When reported, most dislocations occurred within the first year postoperatively (73%). Nearly 7% of patients required an unplanned reoperation following surgery. Conclusion: Osseous stabilization shoulder surgery using original or modified Bristow and Latarjet procedures has a 30% complication rate. Rates of recurrent dislocation and reoperation were 2.9% and 7%, respectively. Mild loss of external rotation is common. Reoperation rates were lower following all-arthroscopic techniques. There was a greater loss of postoperative external rotation with all-arthroscopic surgery. [ABSTRACT FROM AUTHOR]

Background: Bone defects play a role in recurrent instability. There is no universal method to quantify humeral head defects. The purpose of this study is to assess the accuracy of 2-dimensional computed tomography (CT) scan measurements of Hill-Sachs lesions. Materials and methods: Six Hill-Sachs defects were created in anatomically shaped bone substitutes. The samples were scanned with a 3-dimensional laser scanner. Maximum width and depth were measured and used as the true measurement. The samples underwent routine CT scanning, and 5 physicians measured maximum width and depth on each plane independently. The intraclass correlation coefficient (ICC) was used to assess agreement. Percent error and paired t test were used for statistical analysis (P < .05 denoted significance). Results: The ICC between observers was 0.879 (95% confidence interval, 0.780-0.946) and 0.721 (95% confidence interval, 0.543-0.865) for the depth and width measurement, respectively. The ICC was good between individual observers and the true measurement (range, 0.765-0.956). Individual observers were more accurate in depth rather than width measurements. The mean overall percent error of the depth and width measurements for the 6 defects was calculated: coronal, 19.2% ± 13.6%; sagittal, 11.8% ± 8.2%; and axial, 13.6% ± 8.4%. Conclusions: The depth of Hill-Sachs lesions can be reliably assessed using CT scan. Observers consistently underestimated width in all imaging planes. Overall, sagittal- and axial-plane measurements are more accurate for evaluation of these defects than the coronal plane. Future studies using 3-dimensional CT may be helpful to further quantitatively assess the size of the Hill-Sachs lesion, including width and volume. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to investigate the effect of differing storage medium on osteochondral plug diameter. Methods: Four storage conditions were evaluated: air, hypotonic solution (sterile water), isotonic saline solution (0.9% sodium chloride), and hypertonic saline solution (3.0% sodium chloride). Four osteochondral plugs were acquired (4.5-mm harvesting system) from each of 10 fresh calf femurs and randomized to 1 of 4 storage media (N = 40). Micro–computed tomography was used to evaluate the precise diameter of each plug. After a time 0 scan, each plug was placed in a designated storage medium and rescanned at 3 time points over approximately 1 hour. A region of interest was identified from approximately 1 to 6 mm proximal to the tidemark. Custom software automatically calculated the diameter of each plug. Results: The time 0 plug diameter (mean ± 95% confidence interval) for all specimens was 4.66 ± 0.01 mm. There were no significant differences between any of the groups at the baseline scan. There were also no significant differences between the time 0 and subsequent scans of the unsubmerged specimens. However, all of the liquid solutions (hypertonic, isotonic, and hypotonic) resulted in a significant increase in diameter from their baseline scans (P < .05), indicating that a cause may be increased extracellular matrix fluid pressure. Conclusions: Placing an osteochondral plug in a liquid solution increased the diameter of the subchondral bone. Size increase from the storage medium appeared to level off within 14 minutes after placement in solution. Clinical Relevance: Increases in diameter of the plug may alter the ease of insertion of the graft, possibly increasing contact pressure on cartilage during plug implantation. [ABSTRACT FROM AUTHOR]

This article talks about navicular stress fractures. According to the authors, the kinematics of the tarsal joints and the blood supply to the navicular bone contribute to the characteristic location of stress fractures in the tarsal navicular bone. They said aggressive operative and nonoperative treatments are necessary because the fractures are high-risk.

Purpose: To define the anatomy of the lateral antebrachial cutaneous nerve (LACN) and the superficial radial nerve (SRN) in relation to easily identifiable landmarks in the dorsoradial forearm to minimize the risk to both nerves during surgical approaches to the dorsal radius. Methods: In this study 37 cadaveric forearms and 20 patients having distal radius external fixation were dissected to identify these nerves in relation to various anatomic landmarks. Results: Based on these dissections the anatomy was divided into 2 zones that can be identified by easily visible and palpable landmarks. Zone 1 extends from the elbow to the cross-over of the abductor pollicis longus with the extensor carpi radialis brevis and longus. Zone 2 is distal to the cross-over. In zone 1 the 2 nerves can be differentiated through limited incisions based on their depth and anatomic location. Within this zone the SRN is deep to the brachioradialis until 1.8 cm proximal to zone 2 (9 cm proximal to the radial styloid), where it becomes superficial and pierces the fascia of the mobile wad and then remains deep to the subcutaneous fat. In contrast the LACN pierces the fascia between the brachialis and biceps muscles at the level of the elbow. In all specimens the LACN ran parallel to the cephalic vein within the subcutaneous fat. In 31 specimens it ran volar to the vein and in 5 specimens the nerve crossed under the cephalic vein at the elbow and ran dorsal to the vein in the forearm. One specimen had 2 branches with 1 on either side of the vein. Differentiation of these nerves was found to be possible through limited incisions in zone 1 during placement of external fixation pins for distal radius fractures. The LACN always was located in the superficial fat running with the cephalic vein, whereas the SRN was deeper to this nerve either covered by the brachioradialis or closely adherent to it within the investing fascia of the mobile wad. In zone 2 the nerves arborized and ran in the same tissue plane, making differentiation through limited incisions difficult. Conclusions: Dividing forearm anatomy into zones aids in understanding the complex 3-dimensional anatomy. Recognition of the consistent location of both the LACN and SRN facilitates surgical exposure. This allows localization through limited incisions during nerve repair and hardware placement, thereby enhancing uncomplicated and favorable outcomes. [Copyright &y& Elsevier]