Sydney C. Karnovsky

Effect of Complete Syndesmotic Disruption and Deltoid Injuries and Different Reduction Methods on Ankle Joint Contact Mechanics

Background: Syndesmotic injuries can be associated with poor patient outcomes and posttraumatic ankle arthritis, particularly in the case of malreduction. However, ankle joint contact mechanics following a syndesmotic injury and reduction remains poorly understood. The purpose of this study was to characterize the effects of a syndesmotic injury and reduction techniques on ankle joint contact mechanics in a biomechanical model. Methods: Ten cadaveric whole lower leg specimens with undisturbed proximal tibiofibular joints were prepared and tested in this study. Contact area, contact force, and peak contact pressure were measured in the ankle joint during simulated standing in the intact, injured, and 3 reduction conditions: screw fixation with a clamp, screw fixation without a clamp (thumb technique), and a suture-button construct. Differences in these ankle contact parameters were detected between conditions using repeated-measures analysis of variance. Results: Syndesmotic disruption decreased tibial plafond contact area and force. Syndesmotic reduction did not restore ankle loading mechanics to values measured in the intact condition. Reduction with the thumb technique was able to restore significantly more joint contact area and force than the reduction clamp or suture-button construct. Conclusion: Syndesmotic disruption decreased joint contact area and force. Although the thumb technique performed significantly better than the reduction clamp and suture-button construct, syndesmotic reduction did not restore contact mechanics to intact levels. Clinical Relevance: Decreased contact area and force with disruption imply that other structures are likely receiving more loads (eg, medial and lateral gutters), which may have clinical implications such as the development of posttraumatic arthritis.

Biomechanical Analysis of Suture Anchor vs Tenodesis Screw for FHL Transfer

Background: Chronic Achilles injury is often treated with flexor hallucis longus (FHL) tendon transfer to the calcaneus using 1 or 2 incisions. A single incision avoids the risks of extended dissections yet yields smaller grafts, which may limit fixation options. We investigated the required length of FHL autograft and biomechanical profiles for suture anchor and biotenodesis screw fixation. Methods: Single-incision FHL transfer with suture anchor or biotenodesis screw fixation to the calcaneus was performed on 20 fresh cadaveric specimens. Specimens were cyclically loaded until maximal load to failure. Length of FHL tendon harvest, ultimate load, stiffness, and mode of failure were recorded. Results: Tendon harvest length needed for suture anchor fixation was 16.8 ± 2.1 mm vs 29.6 ± 2.4 mm for biotenodesis screw (P = .002). Ultimate load to failure was not significantly different between groups. A significant inverse correlation existed between failure load and donor age when all specimens were pooled (ρ = −0.49, P < .05). Screws in younger specimens (fewer than 70) resulted in significantly greater failure loads (P < .03). No difference in stiffness was found between groups. Modes of failure for screw fixation were either tunnel pullout (n = 6) or tendon rupture (n = 4). Anchor failure occurred mostly by suture breakage (n = 8). Conclusion: Adequate FHL tendon length could be harvested through a single posterior incision for fixation to the calcaneus with either fixation option, but suture anchor required significantly less graft length. Stiffness, fixation strength, and load to failure were comparable between groups. An inverse correlation existed between failure load and donor age. Younger specimens with screw fixation demonstrated significantly greater failure loads. Clinical Relevance: Adequate harvest length for FHL transfer could be achieved with a single posterior incision. There was no difference in strength of fixation between suture anchor and biotenodesis screw.

Operative treatment of lateral ligament instability

Purpose of reviewAnkle sprains, which account for 40% of sports injuries in the USA, can lead to chronic ankle instability. Chronic ankle instability can be classified as functional, mechanical, or a combination of both and is diagnosed using a combination of a physical exam, an MRI, and stress radiographs. This review focuses on different approaches to treatment, including non-operative and operative techniques, of chronic ankle instability, including reviewing traditional procedures as well as more novel and newer techniques.Recent findingsBased on existing literature, non-operative treatment should always precede operative treatment of chronic ankle instability. If rehabilitation fails, Brostrom-Gould type ankle stabilization has been the preferred surgical option. Recent literature suggests that arthroscopic repair might reduce recovery time and improve outcomes in certain populations; however, there are higher rates of complication following these surgeries. In more high-risk populations, some literature reports that ligament repair with peroneus brevis transfer could be a more effective treatment option.SummaryCurrently, varying surgical techniques exist for the treatment of chronic ankle instability. While the more recently reported techniques show promise, it is important to note that there is little evidence showing they are more successful than traditional techniques. It is imperative that future studies focus on outcomes and complication rates of these newer procedures.

Optimal Starting Point for Fifth Metatarsal Zone II Fractures: A Cadaveric Study

Background: Identifying the optimal starting point for intramedullary fixation of tibia and femur fractures is well described in the literature using a retrograde or anterograde technique. This technique has not been applied to the fifth metatarsal, where screw trajectory can cause iatrogenic malreduction. The generally accepted starting point for the fifth metatarsal is “high and inside” to accommodate the fifth metatarsal’s dorsal apex and medial curvature. We used a retrograde technique to identify the optimal starting position for intramedullary fixation of fifth metatarsal fractures. Methods: Five matched cadaveric lower extremity pairs were dissected to the fifth metatarsal neck. An osteotomy was made to access the intramedullary canal. A retrograde reamer was passed to the base of the fifth metatarsal to ascertain the ideal entry point. Distances from each major structure on the lateral aspect of the foot were measured. Computed tomography scans helped assess base edge measurements. Results: In 6 of 10 specimens, the retrograde reamer hit the cuboid with a cuboid invasion averaging 0.7 mm. The peroneus brevis and longus were closest to the starting position with an average distance of 5.1 mm and 5.7 mm, respectively. Distances from the entry point to the dorsal, plantar, medial, and lateral edges of the metatarsal base were 8.3 mm, 6.9 mm, 9.7 mm, and 9.7 mm, respectively. Conclusion: Optimal starting position was found to be essentially at the center of the base of the fifth metatarsal at the lateral margin of the cartilage. Osteoplasty of the cuboid or forefoot adduction may be required to gain access to this site. Clinical Relevance: This study evaluated the ideal starting position for screw placement of zone II base of the fifth metatarsal fractures, which should be considered when performing internal fixation for these fractures.

Comparison of Juvenile Allogenous Articular Cartilage and Bone Marrow Aspirate Concentrate Versus Microfracture With and Without Bone Marrow Aspirate Concentrate in Arthroscopic Treatment of Talar Osteochondral Lesions

Background: The purpose of this study was to compare the functional and radiographic outcomes of patients who received juvenile allogenic chondrocyte implantation with autologous bone marrow aspirate (JACI-BMAC) for treatment of talar osteochondral lesions with those of patients who underwent microfracture (MF). Methods: A total of 30 patients who underwent MF and 20 who received DeNovo NT for JACI-BMAC treatment between 2006 and 2014 were included. Additionally, 17 MF patients received supplemental BMAC treatment. Retrospective chart review was performed and functional outcomes were assessed pre- and postoperatively using the Foot and Ankle Outcome Score and Visual Analog pain scale. Postoperative magnetic resonance images were reviewed and evaluated using a modified Magnetic Resonance Observation of Cartilage Tissue (MOCART) score. Average follow-up for functional outcomes was 30.9 months (range, 12-79 months). Radiographically, average follow-up was 28.1 months (range, 12-97 months). Results: Both the MF and JACI-BMAC showed significant pre- to postoperative improvements in all Foot and Ankle Outcome Score subscales. Visual Analog Scale scores also showed improvement in both groups, but only reached a level of statistical significance (P < .05) in the MF group. There were no significant differences in patient reported outcomes between groups. Average osteochondral lesion diameter was significantly larger in JACI-BMAC patients compared to MF patients, but size difference had no significant impact on outcomes. Both groups produced reparative tissue that exhibited a fibrocartilage composition. The JACI-BMAC group had more patients with hypertrophy exhibited on magnetic resonance imaging (MRI) than the MF group (P = .009). Conclusion: JACI-BMAC and MF resulted in improved functional outcomes. However, while the majority of patients improved, functional outcomes and quality of repair tissue were still not normal. Based on our results, lesions repaired with DeNovo NT allograft still appeared fibrocartilaginous on MRI and did not result in significant functional gains as compared to MF. Level of Evidence: Level III, comparative series.

Distraction Osteogenesis and Fusion for Failed First Metatarsophalangeal Joint Replacement: Case Series

Hallux rigidus is a progressive osteoarthritic condition, and operative intervention is often required. It can affect gait, lead to a decreased range of motion, particularly dorsiflexion, and can cause stiffness and pain. First metatarsophalangeal (MTP) arthrodesis is the traditional standard treatment for end-stage hallux rigidus and has been repeatedly shown to be the most consistent and successful operative technique. In 1952, first MTP arthroplasty emerged as a new treatment option for end-stage hallux rigidus. First MTP arthroplasty involves prosthetic replacement of the first MTP joint with either a unipolar or bipolar implant and has the potential to improve joint motion and reduce pain. However, arthroplasty involves additional risks, including malposition, implant fracture, stress fracture, arthrofibrosis, and synovitis, all of which can lead to failure. Additionally, failed arthroplasty often leads to a significant amount of first ray shortening, which can make revision surgery a challenge. There is little literature following the long-term results of hemiarthroplasty and total joint arthroplasty, and even less exists describing outcomes of salvage arthrodesis in cases where arthroplasty fails. Brage and Ball reported that many of the hemiarthroplasty implants would fail. Delman et al also reported that arthroplasty procedures to treat hallux rigidus would fail, opining that the compressive and shear stresses placed on the implant surfaces put them at high risk of loosening. Furthermore, unlike the knee and hip, there is little surface area available to establish a strong bone-implant interface. This, combined with higher stresses, particularly during walking and stair-climbing, leads to higher failure rates. In a study comparing arthroplasty and arthrodesis over a 6-year period, 24% of the arthroplasties failed, with 4 converted to an arthrodesis to alleviate pain. Failed implants, once removed, create significant bone loss, which can make the reconstruction operation difficult. Because of the bone loss, the revision arthrodesis usually necessitates bone grafting in order to restore first ray length. Depending on the amount of bone loss, local autologous bone graft may be an option, but in cases with significant loss, grafts from other areas might be necessary as well, increasing the potential rate of failure of the operation. Commonly, surgeons use tricortical iliac crest autograft wedges to manage defects. However, this can have associated morbidity in terms of pain and even fracture. These salvage arthrodesis procedures often have a long time to union and increased rates of nonunion and malunion compared to primary first MTP arthrodesis procedures. To avoid the complications associated with iliac crest bone graft harvest, tricortical allograft wedges have also been used. However, the nonunion rate associated with allograft in foot arthrodesis cases has been reported to range from 9% to 23% and is thus a less favorable option. To improve the chance of healing, many surgeons elect to acutely shorten the first 737481 FAIXXX10.1177/1071100717737481Foot & Ankle InternationalDa Cunha et al research-article2017

Syndesmotic Injury Assessment With Lateral Imaging During Stress Testing in a Cadaveric Model

Background: External rotation, lateral, and sagittal stress tests are commonly used to diagnose syndesmotic injuries, but their efficacy remains unclear. The purpose of this study was to characterize applied stresses with fibular motion throughout the syndesmotic injury spectrum. We hypothesized that sagittal fibular motion would have greater fidelity in detecting changes in syndesmotic status compared to mortise imaging. Methods: Syndesmotic instability was characterized using motion analysis during external rotation, lateral, and sagittal stress tests on cadaveric specimens (n = 9). A progressive syndesmotic injury was created by sectioning the tibiofibular and deltoid ligaments. Applied loads and fibular motion were synchronously measured using a force transducer and motion capture, respectively, while mortise and lateral radiographs were acquired to quantify clinical measurements. Fibular motion in response to these 3 stress tests was compared between the intact, complete lateral syndesmotic injury and lateral injury plus a completely sectioned deltoid condition. Results: Stress tests performed under lateral imaging detected syndesmotic injuries with greater sensitivity than the clinical-standard mortise view. Lateral imaging was twice as sensitive to applied loads as mortise view imaging. Specifically, half as much linear force generated 2 mm of detectable syndesmotic motion. In addition, fibular motion increased linearly in response to sagittal stresses (Pearson’s r [ρ] = 0.91 ± 0.1) but not lateral stresses (ρ = 0.29 ± 0.66). Conclusion: Stress tests using lateral imaging detected syndesmotic injuries with greater sensitivity than a typical mortise view. In addition to greater diagnostic sensitivity, reduced loads were required to detect injuries. Clinical Relevance: Syndesmotic injuries may be better diagnosed using stress tests that are assessed using lateral imaging than standard mortise view imaging.

The Disappearing Phalanx: A Case Report of a Vascular Tumor of the Toe

We report a unique case of an epithelioid hemangioma of the third middle phalanx in which the lesion replaced the phalanx, became symptomatic, and then required resection, bone grafting, and joint arthroplasty. To the best of our knowledge, this is the first report of an epithelioid hemangioma in the toe that was treated using this approach.

Surgical Treatment for Stenosing Peroneal Tenosynovitis

Introduction/Purpose: Stenosing Peroneal Tenosynovitis is an uncommon entity that is equally difficult to diagnose. In our practice, we have found 14 patients with this diagnosis. They were all successfully treated with release of the peroneal tendon sheath and debridement of the calcaneal exostosis. Further, the ultrasound guided anesthetic injection of the tendon sheath preoperatively essential in confirming this diagnosis and evaluating for successful outcomes after surgical intervention.

Ankle Arthroscopy for Diagnosis and Treatment of Full Thickness Cartilage Lesions in the Setting of Ankle Fracture

Category: Ankle, Arthroscopy, Sports Introduction/Purpose: Ankle fractures treated with anatomic open reduction and internal fixation (ORIF) can still be associated with poor clinical outcomes. The presence of radiographically occult intra-articular chondral injury is a known entity, however the clinical relevance in the setting of ankle fractures is not well established. The purpose of this study aims to evaluate the prevalence of chondral lesions, in particular full thickness talar dome lesions, with concurrent arthroscopy in acute ankle fracture ORIF and determine if there is a correlation with patient and fracture characteristics. In addition, we aimed to evaluate the treatment effect on clinical outcomes to establish the role of concurrent arthroscopy in ankle fracture management. Methods: A retrospective chart review was conducted from prospectively collected registry data at the investigators’ institution from 2011 to 2016. All patients that underwent an acute ankle fracture ORIF with concurrent arthroscopy were identified. Patients with concomitant injuries were excluded. Baseline patient and fracture characteristics were recorded. Fracture type by the Lauge-Hansen classification as well as by anatomic location were determined. Charts were reviewed to determine the prevalence and grade of chondral lesions. The treatment performed for each chondral lesion was determined. Clinical outcomes with a minimum of one year follow up were assessed using the Foot and Ankle Outcome Score (FAOS). Results: One hundred and sixteen consecutive patients undergoing acute ankle fracture ORIF with concurrent arthroscopy were included. A chondral lesion was identified in 78% (90/116). Of those, a Grade IV full thickness talar dome chondral lesion was identified in 43% (39/90). Patient age was a significant predictor, with patients less than thirty being less likely to have a chondral injury compared to those greater than thirty (59% vs 85%, p=0.0077). Of the patients that sustained a dislocation at the time of injury, 100% had a chondral lesion which was statistically significant (p=0.039). Patients with complete syndesmosis disruption and instability were also more likely to have a chondral lesion (96% vs 73%, p=0.013). Patients with chondral lesions had statistically significant worse clinical outcomes than those without (Table). Conclusion: Arthroscopy performed concomitantly with ankle ORIF is useful in diagnosing chondral injuries. In particular, full thickness talar dome chondral lesions are quite common. Increased fracture severity, as indicated by the presence of a dislocation at presentation, and a syndesmotic injury may be more likely to present with a chondral lesion and thus should raise suspicion and prompt evaluation. The presence of a concurrent talar chondral injury has a negative impact on clinical outcomes. Concurrent arthroscopy allows for simultaneous diagnosis and acute treatment of full thickness talar lesions.