Iatrogenic Cartilage Damage Research Articles

The pie-crust surgical technique for medial collateral ligament release: enhancing visualization of the medial compartment in knee arthroscopy.

This study presents a comprehensive surgical technique for performing a 'pie-crust' release of the medial collateral ligament (MCL) to enhance visualization of the medial compartment during arthroscopic knee procedures. The primary objective of this research is to improve the precision of diagnosis and treatment for injuries specifically affecting the posterior horn and posterior root of the medial meniscus. Arthroscopic knee procedures have become increasingly common in orthopedic surgery, offering the advantage of minimally invasive techniques for treating a wide range of knee conditions. However, accessing and visualizing the posterior structures within the medial compartment can be challenging. To overcome this limitation, the surgical technique presented in this study offers a systematic approach that includes patient positioning, precise identification of anatomical landmarks, and a detailed, step-by-step procedural description. The process begins with meticulous marking of anatomical landmarks to provide reference points. Precisely identifying the location for the MCL release is of utmost importance. This involves making needle punctures with guidance from arthroscopic visualization and applying valgus strain to the knee as necessary. One of the key advantages of this described surgical technique is its focus on safety and efficacy. Surgeons can work more confidently and precisely by reducing the risk of iatrogenic cartilage damage and facilitating access to the posterior structures within the medial compartment. Clinical outcomes from this approach have demonstrated consistently favorable results, leading to improved patient recovery and reduced complications. Furthermore, it is noteworthy that the postoperative use of a brace is not mandatory, adding to the appeal of this technique for both patients and surgeons. This surgical technique's enhanced visualization and optimized treatment outcomes make it a valuable tool in the arsenal of orthopedic surgeons specializing in knee arthroscopy. In conclusion, this study's surgical technique has the potential to significantly improve the diagnosis and treatment of patients with meniscal injuries in the medial compartment, ultimately leading to better clinical outcomes and patient satisfaction.

Measuring the outcomes of medial meniscectomies with a femoral end medial collateral ligament release and reattachment in patients with a tight knee: a case series

Partial meniscectomies are the most commonly performed arthroscopic knee procedures, however, are complicated by the presence of a tear in the posterior medial compartment (PMC) in tandem with a “tight knee”. This inhibits adequate spacing for instrumentation access, increasing the chances of causing iatrogenic cartilage damage which can progress to early onset osteoarthritis. We present a unique method for increasing the joint space, in such cases, and avoiding cartilage damage, by performing a femoral end medial collateral ligament release and reattachment (MCLR). Patient outcomes were evaluated in two parts. The first part compared the fourteen patients who underwent a MCLR pre- and post-operatively via the Lysholm and Tegner score, VAS pain scale and knee flexion angle. Finally, the MCLR patients were compared via 1:1 propensity score-matching to patients who underwent a valgus maneuver only for a PMC tear. The patients receiving an MCLR showed a statistically significant improvement (p<0.001) within each of the pre- and post-operative measured variables. When compared with 1:1 propensity score matched and unmatched patients, no statistically significant difference was seen between the Lysholm, Tegner and Flexion angle while VAS pain scale did show a difference. For patients requiring a PMM with a “tight knee”, performing an MCLR provides a clinical and functional improvement in symptoms and showed no statistically significant difference when compared with valgus maneuver only patients. Therefore, it is an effective procedure for increasing the joint space in a patient with a tight knee that requires a partial medial meniscectomy (PMM).

DIRECT POSTERIOR KNEE PORTALS USING NEEDLE ARTHROSCOPY: A TECHNICAL FEASIBILITY STUDY

Knee arthroscopy is typically approached from the anterior, posteromedial and posterolateral portals. Access to the posterior compartments through these portals can cause iatrogenic cartilage damage and create difficulties in viewing the structures of the posterior compartments. The purpose of this study was to assess the feasibility of needle arthroscopy using direct posterior portals as both working and visualising portals.For workability, the needle scope was inserted advanced from anterior between the cruciate ligament bundle and the lateral wall of the medial femoral condyle until the posterior compartments were visualised. For visualisation, direct postero-lateral and -medial portals were established. The technique was performed in 9 knees by two experienced researchers.Workability and instrumentation of the posteromedial compartment and meniscus was achieved in 56%. The posterior horns could not be visualised in four specimens as the straight lens could not provide a more medial field of view. Visualisation from the direct medial posterior portal allowed a clear view of the medial meniscus, femoral condyle and posterior cruciate ligament in all specimens. Workability and instrumentation of the posterolateral compartment was not possible with the needle scope.Direct posterior approaches for the posteromedial compartment access are challenging with the current needle scope options and could only be achieved in over 50%. The postero-lateral compartment was not accessible. An angled lens or a flexible Needle scope would be better suited for developing this technique further.

Osteochondritis Dissecans of the Talus: A New Transmalleolar Fixation Technique

Background: Conservative management is the first line of treatment in most osteochondritis dissecans (OCD) cases and can be sufficient for small and stable lesions in skeletally immature patients. Unstable lesions commonly require surgical interventions and may need fixation. The standard surgical approach to fix posteromedial lesions of the talus involves an osteotomy of the medial malleolus. This technique is invasive and requires multiple weeks of immobilization after the surgery. In this video, we present a minimally invasive transmalleolar approach used for the fixation of an OCD lesion of the talus. Indications: The main indication for this procedure is the failure of conservative management with persistent ankle pain and functional impairment of an unstable osteochondral lesion with poor potential for revascularization. Technique Description: There are 3 key steps to this surgery: ankle arthroscopy, retroarticular drilling, and transmalleolar fixation. The transmalleolar approach is achieved by creating a tunnel through the medial malleoli oriented toward the lesion. To do so, the surgeon combines fluoroscopy and ankle arthroscopy to first insert a Kirschner wire (K-wire) through the medial malleoli. Once the correct orientation is confirmed, a 4.5-mm cannulated drill bit is used to create the tunnel. Arthroscopic visualization is used to avoid iatrogenic cartilage damage during drilling. Once the tunnel is created, ankle dorsiflexion and plantar flexion are used to access the entire lesion and insert screws. The malleolar tunnel is then filled with a bone graft and the wound closed. The patient is immobilized for 2 weeks after which gentle range of motion is initiated. The patient remains non-weight-bearing for 2 months and is then allowed to bear weight using a boot. Results: Transmalleolar fixation for osteochondritis dissecans of the talus is a minimally invasive procedure that does not require an osteotomy of the medial talus. This approach permits early postoperative range of motion and decreases postoperative pain and edema, but the adequate positioning of the tunnel can prove challenging. Conclusion: Transmalleolar approach to the talus is minimally invasive and allows adequate fixation of certain osteochondral lesions. Studies comparing the reoperation and complication rate with the standard malleolar osteotomy are lacking and need to be performed. The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.

Needle-Arthroscopic Ankle Lateral Ligament Repair Using a Knotless Suture Anchor

Category:Arthroscopy; Ankle; Arthroscopy; SportsIntroduction/Purpose:Arthroscopic techniques have been increasingly used to repair the anterior talofibular ligament (ATFL) for lateral ankle instability, however there are still concerns on complications, such as nerve injury, iatrogenic cartilage damage and wound scar. Additionally, standard suture anchors can cause prominent knots. Recently, a novel needle-arthroscopic system (NanoScopeTM) has been introduced, with a 1.9-mm diameter arthroscope and semirigid frame, which can reduce conventional arthroscopic-related complications by minimizing the skin incisions and provide excellent visualization without ankle distraction due to its small and semirigid features. The purpose of this surgical technical note is to describe a new, very minimally invasive surgical technique for the ATFL repair using this needle-arthroscopy with a knotless suture anchor, which has the potential to reduce both conventional arthroscopic-related and knot-related complications.Methods:We have developed a novel surgical treatment of the ATFL repair for lateral ankle instability in a cadaveric model. The arthroscopic system (NanoScopeTM, Arthrex, Naples, FL) is used during the procedures. The handpiece tube is 9.5-cm long, semi-rigid and has a 1.9-mm outer diameter. The scope's direction of view is 0°, with a 120° field of view. The patient is placed in a supine position and no distraction is applied to the ankle joint. Standard anteromedial and anterolateral portals are first used. An accessory anterolateral (AAL) portal is then created around 1.5 cm anterior to the tip of the fibula, of which the portal position is determined under the visualization through the anterolateral portal.Results:Almost all of the talar and tibial surfaces are reachable without distraction, due to its small and semirigid features. There is no difficulty problem obtaining proper visualization of the ATFL and the surrounding structures during the whole procedures, due to a wide 120°-field of view. The major steps of the procedure are (1) suture anchor insertion into the distal fibula through the AAL portal using a Knotless SutureTak Anchor (Arthrex), (2) penetration of suture string into the ATFL remnant using a Micro SutureLassoTM (Arthrex), (3) capture of the ATFL remnant using a suture-relay technique, (4) reattachment of the ATFL remnant by pulling out the passing wire without knot-tying, in the dorsiflexed ankle position (Figure). All skin-incisions are tiny and require only paper skin closures. This method requires neither blunt dissection of subcutaneous tissue to pass the suture nor knot-tying to reattach the ATFL.Conclusion:Our technique is a simple, feasible, and very minimally invasive anatomic repair of the ATFL for lateral ankle instability using a 1.9-mm diameter needle-arthroscopy with a knotless suture anchor. However, the long-term clinical results need to be evaluated in future studies.

Articular Cartilage of the Syndesmosis: Avoiding Iatrogenic Cartilage Injury During Syndesmotic Fixation.

The optimal surgical management of syndesmosis injuries consists of internal fixation between the distal fibula and tibia. Much of the available data on this joint details the anatomy of the syndesmotic ligaments. Little is published evaluating the distribution of articular cartilage of the syndesmosis, which is of importance to minimize the risk of iatrogenic damage during surgical treatment. The purpose of this study is to describe the articular cartilage of the syndesmosis. Twenty cadaveric ankles were dissected to identify the cartilage of the syndesmosis. Digital images of the articular cartilage were taken and measured using calibrated digital imaging software. On the tibial side, distinct articular cartilage extending above the plafond was identified in 19/20 (95%) specimens. The tibial cartilage extended a mean of 6 ± 3 (range, 2-13) mm above the plafond. On the fibular side, 6/20 (30%) specimens demonstrated cartilage proximal to the talar facet, which extended a mean of 24 ± 4 (range, 20-31) mm above the tip of the fibula. The superior extent of the syndesmotic recess was a mean of 10 ± 3 (range, 5-17) mm in height. In all specimens, the syndesmosis cartilage did not extend more than 13 mm proximal to the tibial plafond and the syndesmotic recess did not extend more than 17 mm proximal to the tibial plafond. Syndesmosis fixation placed more than 13 mm proximal to the tibial plafond would have safely avoided the articular cartilage in all specimens and the synovial-lined syndesmotic recess in most. This study details the articular anatomy of the distal tibiofibular joint and provides measurements that can guide implant placement during syndesmotic fixation to minimize the risk of iatrogenic cartilage damage.

Medial collateral ligament release during knee arthroscopy: key concepts.

Complete access to the posterior medial compartment of the knee may represent a technical challenge during arthroscopy in patients with a tight tibiofemoral joint space.Medial collateral release reduces direct iatrogenic cartilage damage in the medial compartment of the knee through manipulation with instruments.We recommend performing medial collateral release in surgeries that access the posteromedial compartment (e.g. partial meniscectomy for ruptures of the posterior horn of medial meniscus or posterior root repairs) when the patient has a tight tibiofemoral joint space.There are two main techniques to perform medial collateral release: inside-out and outside-in. Regardless of the technique used, releasing medial ligament structures is a safe and effective method to be used in the diagnosis and treatment of injuries to the medial compartment. Cite this article: EFORT Open Rev 2021;6:669-675. DOI: 10.1302/2058-5241.6.200128

Evaluation of primary hip arthroscopy complications in mid-term follow-up: a multicentric prospective study.

Hip arthroscopy is a common procedure in hip preservation surgery. Its complication rate is relatively low. This prospective multicentric study evaluates complication rate in patients undergoing primary hip arthroscopy. The study cohort consisted of 908 patients mean age of 37years (14-67years). Patients were prospectively included in the study in the years 2009-2017. All complications were recorded and evaluated. The minimum follow-up was 36months. Results were statistically evaluated and risk factors for complications were identified. The overall complication rate was 7.3% (67/908 cases), the minor complication rate of 4.9% (45/908 cases) and the major complication rate 2.4% (22/908 cases). The most common severe complications were iatrogenic cartilage damage and instrument breakage, while the most common minor complications were perineal hypoaesthesia and heterotopic ossifications. The conversion rate to total hip replacement was 4.2% (39/908 patients). Hip arthroscopy is a safe procedure with low complication rates. Surgeon training and experience greatly influence the complication rates.

Needle arthroscopy of the radiocarpal and middle carpal joints in standing sedated horses.

To develop a technique for standing diagnostic needle arthroscopy of the radiocarpal and middle carpal joints in standing sedated horses. Experimental study. Six cadaveric forelimbs (phase 1) and six healthy horses (phase 2). In phase 1, six cadaveric forelimbs were used to assess needle arthroscopic evaluation of both joints. Six healthy horses were subsequently enrolled in phase 2 to validate the procedure in live animals. The joint was maintained in flexion with a custom-made splint and base. In phase 1, needle arthroscopy allowed thorough evaluation of the dorsal and palmar recesses of both joints with traditional arthroscopic portals. In phase 2, joint evaluation was also thorough but only dorsal approaches were performed. All horses underwent radiocarpal joint arthroscopy, whereas the middle carpal joint was evaluated in only three of six horses because of limb movement. The technique was quickly performed and well tolerated by all horses. Complications included moderate movement, mild iatrogenic cartilage damage, and mild hemarthrosis. Standing needle arthroscopy allowed thorough evaluation of the dorsal aspect of both joints, although only three of six middle carpal joints were assessed because of movement limitations. The proposed technique offers an alternative diagnostic tool for radiographically silent intra-articular lesions of the carpus while initially avoiding the cost and risks associated with general anesthesia. Arthroscopy of a single joint is recommended to minimize risks associated with movement during the procedure.

Iatrogenic Articular Cartilage Injury in Arthroscopic Hip and Knee Videos and the Potential for Cartilage Cell Death When Simulated in a Bovine Model

To determine the incidence and characterize the severity of iatrogenic cartilage injuries. Technique videos of arthroscopic femoral acetabular impingement procedures and meniscus repairs on VuMedi (n= 85) and Arthroscopy Techniques (n= 45) were reviewed and iatrogenic cartilage injuries were identified and graded (minor, intermediate, and major injury) by 2 independent reviewers. To demonstrate that even minor injuries on a cellular scale result in damage, a bovine osteochondral explant was used to create comparable minor iatrogenic injuries at varied forces that do not disrupt the articular surface (1.5 N, 2.5 N, and 9.8 N). Dead chondrocytes at the site of injury were stained with ethidium homodimer-2 and imaged with an Olympus FV1000 confocal microscope. χ2 tests were used for analysis; all results with P < .05 were considered significant. In total, 130 videos of arthroscopic meniscus and femoral acetabular impingement procedures were analyzed and the incidence of iatrogenic cartilage injury was 73.8%. There were 110 (70.0%) minor, 35 (22.3%) intermediate, and 11 (7.0%) major iatrogenic injuries. All forces tested in the minor injury bovine model resulted in chondrocyte death at the site of contact. Iatrogenic articular cartilage injuries are common in arthroscopy, occurring in more than 70% of the surgeon-published instructional videos analyzed. At least some chondrocyte death occurs with minor simulated iatrogenic injuries (1.5 N). The high rate of cartilage damage during arthroscopic technique videos likely under-represents the true incidence in clinical practice. Cell death occurs in the bovine minor injury model with minimal contact forces. This suggests iatrogenic cartilage damage during arthroscopy could contribute to clinical outcomes.

The Outside-In, Percutaneous Release of the Medial Collateral Ligament for Knee Arthroscopy

The outside-in, percutaneous release of the medial collateral ligament (MCL) is a technique used to increase the medial tibiofemoral joint space during arthroscopy to facilitate the use of instrumentation and improve visualization without causing iatrogenic cartilage damage. A recent systematic review of the literature has shown this technique to be efficacious and safe, with no evidence of associated short- or long-term complications. This technique has been used for this indication by the senior author without requiring any deviation from our institution’s standard protocol for knee arthroscopy. In an attempt to standardize this technique’s utilization and allow for further evaluation in the literature, the senior author’s method for this percutaneous, outside-in approach of “pie crusting” the MCL is described.

InternalBrace Has Biomechanical Properties Comparable to Suture Button but Less Rigid than Screw in Ligamentous Lisfranc Model

Category:Midfoot/Forefoot, TraumaIntroduction/Purpose:Lisfranc injuries occurring between the medial cuneiform and base of the 2nd metatarsal require anatomic fixation. Suture button and screws are standard techniques for fixation, but the screw may decrease physiologic motion, whereas suture buttons may cause increased soft tissue irritation and iatrogenic cartilage damage. Potential benefits of the InternalBrace include physiologic motion, decreased iatrogenic damage, collagen ingrowth, limited bony erosion and decreased soft tissue irritation. In light of these potential benefits, no studies have investigated the biomechanical properties of the InternalBrace in a Lisfranc injury model. However, it is unknown whether there is significant difference in the biomechanical properties of the IB compared to the screw, or SB during load to failure, and cyclical loading.Methods:Three groups of sawbones were fixed together with either a 3.5 mm screw, SB, or IB, composed of a curved button, fibertape, and 4.75 mm biotenodesis screw. Sawbone constructs were held in a mechanical testing system (Model 809, MTS Systems Corp, Minneapolis MN). The first three groups of 10 were loaded in axial tension at 0.5mm/sec until failure to determine load-displacement data. Yield, stiffness, ultimate strength (US), yield energy, post-yield energy and ultimate strength energy were calculated. Three more groups of 8 constructs were loaded in-vitro at cyclical physiologic loads until displacement of 1.5 mm occurred. Constructs were first loaded for 10,000 cycles at 69 N (estimate for 50% body weight or assisted walking). Surviving specimens were loaded at 138 N (normal walk) for an additional 10,000 cycles and then 207 N (jog) for an additional 10,000 cycles. Displacement was recorded. The biomechanical properties were then compared between groups.Results:When loaded in axial tension at 0.5mm/sec until failure, the screw was found to be the stiffest construct (2,240 N/mm), while the InternalBrace (200 N/mm) was stiffer than the suture button (133 N/mm). Qualitatively, the InternalBrace was also found to hold load more consistently and for larger displacement prior to failure when compared to the suture button. Cyclic loading was performed with 10,000 cycles of 69 N, 138 N, and 207 N. The screw had the greatest resistance to fatigue. The InternalBrace maintained stiffness as well or better than the suture button, but the fatigue life was shorter than that of the suture button.Conclusion:To our knowledge, the biomechanical properties of the IB have not been compared to screw and SB for ligamentous lisfranc injuries. This study gives valuable information about the mechanical integrity of InternalBrace and supports continued use. However, further studies are warranted before making conclusions regarding early weight bearing.

Flexible Fixation for Ligamentous Lisfranc Injuries

Category:Midfoot/ForefootIntroduction/Purpose:Surgical outcomes of Lisfranc injuries depend on achieving an anatomical and stable reduction. Severity of injury defines the best treatment option and surgical techniques vary from internal fixation to arthrodesis. While effective, limitations of commonly used metal implants include iatrogenic articular cartilage damage, implant breakage and need for implant removal. Additionally, these surgical techniques do not preserve tarsometatarsal (TMT) joint motion.This report demonstrates a novel, easy and inexpensive surgical technique to stabilize TMT joint instability utilizing “flexible fixation” utilized in a case series of 8 patients.Methods:A dorsal approach over the second metatarsal is performed in a standard fashion, after careful dissection and direct visualization of the joint, the TMT joint is anatomically reduced and stabilized with k-wires avoiding damage of the cartilage. Two 2.7 or 3.5 screws with washers are placed from dorsal to plantar in the base of the metatarsal and in the respective tarsal bone to serve as posts. A non-absorbable #2 FiberWire (Arthrex, Naples, Florida) is looped 3 to 5 times in a Figure-of-8 fashion around the screws beneath the washers, tensioned, knotted and secured by tightening the screws. Repeat fluoroscopic stress views are performed to ensure stability of the TMT joint.Results:N/AConclusion:For selected patients with Lisfranc injuries demonstrating no significant comminution or gross instability, flexible fixation using sutures is a promising technique due its potential benefits over trans-articular screws or bridge-plating techniques. This technique is inexpensive, avoids iatrogenic cartilage damage and subsequent removal of hardware.

Evaluation of four techniques for injection of the proximal interphalangeal joint in horses.

To describe a dorsoproximal midline (DPM) standing technique for proximal interphalangeal joint (PIPJ) injection and to compare it to established dorsolateral flexed (DLF), palmaroproximal (PP), and dorsolateral standing (DLS) techniques. Ex vivo study. Sixty cadaver equine thoracic limbs. Limbs were divided into four groups (n = 15 each group), DLF, DPM, PP, and DLS. For each technique, three operators injected radiopaque contrast and methylene blue into the PIPJ in five limbs. The number of attempts required was recorded. Successful injection was confirmed by radiographic presence of contrast media within the PIPJ. Iatrogenic cartilage damage was assessed by gross examination. Statistical analysis was performed by Wilcoxon signed-rank test (P < .05). The overall success rates were 86.6% to 93.3%. Although there was no difference in success rate, the frequency of needle repositioning was influenced by injection technique (P = .009). Dorsolateral standing had the highest mean ± SD value of attempts required to insert the needle in the joint space (2.62 ± 1.94). Injection technique influenced cartilage damage (P = .025), with the highest frequency recorded for DLS. All four techniques for injecting the PIPJ were highly successful; DLS was associated with the highest number of needle repositionings and the highest incidence of iatrogenic injury to cartilage. Dorsolateral flexed should be considered as an alternative to the DLS technique to reduce iatrogenic cartilage injury when injecting the PIPJ. Dorsoproximal midline and DLF techniques have success rates comparable to traditional techniques, with lower incidence of iatrogenic cartilage damage in cadaver limbs.

Evaluation of a self-retaining distractor for hip joint arthroscopy in toy breed dogs

BackgroundHip arthroscopy has become a viable option over the last few years for small animal orthopedic diseases, including hip dysplasia, osteoarthritis, and joint evaluation. However, the narrow joint spaces make it difficult to manipulate the instrument, and depth of tissues make it difficult to distract the joint space. In addition, it is very difficult to maintain consistent distraction over time with a manual distraction due to hand fatigue. To overcome these difficulties, distractors are used in human medicine to improve safety and accuracy of arthroscopy. Therefore, in this study, distractor devices were applied to hip joints in small toy breed dogs to evaluate their technical efficacy. Potential iatrogenic neurovascular and articular damage were also evaluated by comparing two techniques for performing hip joint arthroscopy: the self-retaining distractor and external manipulation.ResultsThe mean ± SD of the joint distraction distance was 8.88 ± 3.54 mm in the self-retaining distraction group and 2.37 ± 0.82 mm in the manual traction group. As the joint space increased, surgeons could more easily place an arthroscopy portal and more comfortably manipulate the instrument with a distractor device. Furthermore, the acetabular cartilage damage (p = 0.004) was significantly greater in the external manipulation group, but articular damage to the femoral head (p = 0.940) was similar in both groups.ConclusionThe results of this study revealed that use of a distractor device can be a viable option for performing hip arthroscopy in small animals. The device significantly improved the surgeon’s performance without surgical assistance, and it reduced iatrogenic cartilage damage compared with manual traction. Further study is needed to quantify neurapraxia associated with distractor placement.

Orthopaedic surgeon attitudes towards current limitations and the potential for robotic and technological innovation in arthroscopic surgery.

To determine the perceptions of surgeons at both consultant and resident level to the difficulties of performing knee arthroscopy and to determine their willingness to adopt robotic technology. A questionnaire was designed to discern the attitude of orthopaedic consultants and residents to the technical challenges of performing knee arthroscopy and the possible role of robotically enhanced surgery. The questionnaire included 31 questions across five key domains. Iatrogenic damage to articular cartilage was thought to occur in at least 1 in 10 cases by 50% of respondents with 15% believing that it occurred in every case. One hundred or more procedures were thought to be necessary to overcome the learning curve by 40% of respondents and 77.5% believed that 50 procedures or above were necessary. Ninety-nine per cent of respondents agreed that higher technical skills would decrease unintended damage. Despite such difficulties with the procedure and no prior experience with robotic surgery, 47% of respondents see a role for semiautonomous arthroscopic systems in the future. Surgeons believe that knee arthroscopy is a difficult procedure with a long learning curve and a high incidence of iatrogenic cartilage damage. Many find it ergonomically challenging and have frustration with current tools and technology. This is the first study that highlights surgeons' difficulties performing knee arthroscopy despite the commonly held attitudes that it is a straightforward procedure. Systems that are able to decrease these problems should improve patients' outcomes and decrease the risk of harm.

An Anatomical Study on the Safe Placement of Orthopedic Hardware for Syndesmosis Fixation.

Articular cartilage and bony contact at the distal tibiofibular cartilage contact zone (TFCCZ) is variable. The appropriate placement of syndesmotic hardware would benefit from a more accurate characterization of the proximal extent of the TFCCZ allowing surgeons to place hardware that simultaneously improves biomechanical stability and decreases the risk of iatrogenic cartilage damage. In addition, Ilizarov wire fixation through the distal fibula and tibia can pass through the syndesmosis recess. Anatomically defining the proximal extent of this recess can help decrease the risk of inadvertent capsular penetration. This study anatomically defines the TFCCZ and syndesmosis recess establishing a safe and biomechanically advantageous distance from the plafond for orthopedic fixation. This study measured the height of the TFCCZ and the syndesmotic recess in 3158 anatomical and cadaveric specimens. A TFCCZ was present in 59% of the Robert J. Terry Anatomical Collection specimens. Maximal height of the TFCCZ averaged 5.7±1.7 mm (99% confidence interval [CI], 5.6-5.8 mm) for anatomical specimens and 5.6±1.6 mm (99% CI, 4.6-6.5 mm) for cadaveric dissections. The maximum TFCCZ height was 11.71 mm. Maximal height of the syndesmotic recess averaged 12.8±2.1 mm for anatomical specimens and 13.7±2.7 mm for cadaveric specimens. The "3 cm rule" appears to be appropriate for fine wire fixation accounting for capsular distension that can be associated with injuries but not applicable for syndesmotic fixation. There is a less than 0.1% chance of encountering the TFCCZ cartilage at 10.9 mm above the plafond and a less than 0.01% chance at 12 mm above the plafond. [Orthopedics. 2017; 40(2):e329-e333.].

Feasibility of Stifle Medial Meniscal Release in Toy Breed Dogs with and without a Joint Distractor.

To investigate the feasibility of medial meniscal release (MMR) during stifle arthroscopy in toy breed dogs with and without a joint distractor. Experimental cadaveric study. Stifles (n = 40) from 20 canine cadavers (1.8-5.1 kg). Paired stifles were randomly assigned to the joint distractor group and the control group (n = 20 each). All stifles underwent arthroscopic transection of the cranial cruciate ligament followed by a release of the caudomedial meniscotibial ligament. After the procedures, all stifles were disarticulated. The degree of released meniscus was recorded subjectively by 5% increments. A MMR success was defined as a complete transection. The areas of femoral and tibial articular cartilage damage were calculated using india ink staining and digital imaging. The results were compared between groups and odds ratios were calculated. All stifle arthroscopies were successful. The success rate of MMR was significantly higher (P = .013) with a joint distractor than without a joint distractor. MMR was 7.4 times more likely to succeed with a joint distractor than without a joint distractor. The distal femoral articular cartilage was significantly more damaged (P = .011) in the stifles without a joint distractor than in the stifles with a distractor. No difference was found between the 2 groups for damage to the tibial cartilage (P = .058). Stifle arthroscopic MMR is feasible in toy breed dogs. Using a joint distractor is recommended for arthroscopic treatment based on our results because it significantly reduced the rate of incomplete release as well as iatrogenic cartilage damage.

A novel implantation technique for engineered osteo-chondral grafts

We present a novel method to support precise insertion of engineered osteochondral grafts by pulling from the bone layer, thereby minimizing iatrogenic damage associated with direct manipulation of the cartilage layer. Grafts were generated by culturing human expanded chondrocytes on Hyaff-11 meshes, sutured to Tutobone spongiosa cylinders. Through the bone layer, shaped to imitate the surface-contours of the talar dome, two sutures were applied: the first for anterograde implantation, to pull the graft into the defect, and the second for retrograde correction, in case of a too deep insertion. All grafts could be correctly positioned into osteochondral lesions created in cadaveric ankle joints with good fit to the surrounding cartilage. Implants withstood short-term dynamic stability tests applied to the ankle joint, without delamination or macroscopic damage. The developed technique, by allowing precise and stable positioning of osteochondral grafts without iatrogenic cartilage damage, is essential for the implantation of engineered tissues, where the cartilage layer is not fully mechanically developed, and could be considered also for conventional autologous osteochondral transplantation.

ARTHROSCOPY OF THE PROXIMAL INTERPHALANGEAL JOINTS OF THE FINGER

Cadaveric studies were carried out to evaluate the technique, portals and possible indications for arthroscopy of the proximal interphalangeal joints of the finger. We suggest horizontal placement of the hand instead of using a traction tower, as it is important to be able to flex the joint freely. The recommended arthroscopic portals are either between the central slip and the lateral bands of the extensor mechanism or between the lateral band and the collateral ligament. A blunt technique of introduction is used to avoid iatrogenic cartilage damage and possible digital nerve injury.