Video analysis of Achilles tendon ruptures in professional male football (soccer) reveals underlying injury patterns and provides strategies for injury prevention.

PURPOSE: In professional football (soccer), Achilles tendon ruptures are severe injuries. Video analysis promotes a better understanding of the underlying situational and biomechanical patterns, and provides a roadmap for future research to improve the management and prevention of Achilles tendon ruptures. The purpose of this study was to identify injury patterns contributing to acute Achilles tendon ruptures in professional male football players. METHODS: Professional male football players with an acute Achilles tendon rupture were identified using an online database. For every in-competition injury, the corresponding football match was detected. Video footage of the injury was accessed using Wyscout.com or publicly available video databases. Situational patterns and injury biomechanics of the injury frame were independently analysed by two reviewers using a standardised checklist and a motion analysis software. Finally, consensus was reached to describe the main injury patterns of Achilles tendon ruptures in professional male football players. RESULTS: The search identified video footage of 80 Achilles tendon ruptures in 78 players. Most injuries (94%) occurred through indirect or non-contact mechanisms. The kinematic analysis revealed characteristic joint positions at the time of injury consisting of hip extension, knee extension, ankle dorsiflexion, foot abduction, and foot pronation in most cases. The underlying direction of movement was from flexion to extension (knee) and from plantarflexion to dorsiflexion (ankle). Player actions identified as main injury patterns were stepping back (26%), landing (20%), running/sprinting (18%), jumping (13%), and starting (10%). CONCLUSION: Most Achilles tendon ruptures in professional male football players are closed-chain indirect or non-contact injuries. Sudden loading to the plantarflexor musculotendinous unit remains to be the main component for most cases. By achieving a better understanding of underlying injury mechanisms, this study provides new strategies for the prevention of Achilles tendon ruptures. LEVEL OF EVIDENCE: Level IV.

A Biomechanical Analysis of the H-Taping Method Used by Rock Climbers as Prophylactic or Stabilizing Fixation of Partial A2 Pulley Tears.

PURPOSE: Rock climbing can lead to upper-extremity injuries, such as A2 pulley ruptures, leading to the bowstringing of the flexor tendons. Climbing finger positions are specific and can put undue stress on the pulley systems. This causes severe hand dysfunction and is a difficult problem to treat, and prevention is important. Using a cadaveric, experimental model, we evaluated the effectiveness of the H-taping method, commonly used by rock climbers, to prevent and treat A2 pulley tears. METHODS: Using fourteen matched pairs of fresh-frozen cadaveric hands with forearms, four experiments were conducted with 56 paired comparisons evaluating the failure force, fingertip force, and mode of failure (112 total tests). Comparisons were as follows: index fingers- intact versus 50% distal A2 pulley tears without H-taping (control); ring fingers- intact versus H-taping as a prophylactic for A2 pulley tears; little fingers- 50% distal A2 pulley tears with H-tape versus without tape; and middle fingers- H-taping as a prophylactic versus H-taping as a stabilizing treatment of torn pulleys. RESULTS: The mean index finger failure force was significantly higher in intact vs torn A2 pulleys (control). Failure force for intact H-taped fingers was significantly higher than torn H-taped fingers, but no other finger comparisons for failure force were significant. There were no significant findings in comparison of mean fingertip force values in any of the experiments. CONCLUSIONS: We found that H-taping is not effective as prophylaxis against A2 pulley ruptures or as a stabilizing treatment method for partially ruptured pulleys. CLINICAL RELEVANCE: While H-taping has not been recommended as prophylaxis for preventing A2 pulley ruptures, the climbing community has embraced this technique as a preventative measure. The present study provides biomechanical evidence against H-taping for this purpose. Furthermore, it does not appear to aid in increasing fingertip force after injury.

Effect of hyperdry amniotic membrane in preventing tendon adhesion in a rabbit model.

BACKGROUND: No anti-adhesive materials are currently in clinical use for orthopaedic surgery. We developed a hyperdry amniotic membrane (HD-AM) for easy storage and transplantation as amniotic membrane. The purpose of this study was to examine the application of HD-AM to reduce peritendinous adhesions without impairing tendon healing. METHODS: We randomly divided 3 digits (2nd, 3rd, and 4th digits) from each rabbit into three groups: a tendon repair group; a tendon repair with HD-AM group (HD-AM group); and a control group (cast only). The effects of HD-AM on peritendinous adhesions and tendon healing were examined using microscopic, histological, and mechanical analyses in a rabbit flexor digitorum profundus tendon model. RESULTS: Adhesions on macroscopic evaluation of the tendon repair site were significantly smaller in the HD-AM group than in the tendon repair group. Little adhesion formation or foreign body reactions were seen by on histologic evaluation in the HD-AM group. Range of motion following tendon repair was significantly better in the HD-AM group than in the tendon repair group. Maximal tensile strength required to pull the tendon from the site of adhesion was significantly smaller in the HD-AM group than in the tendon repair group. As for tendon repair site, no significant difference was seen between the tendon repair and HD-AM groups. CONCLUSIONS: HD-AM prevented peritendinous adhesion macroscopically, pathologically, and mechanically without impairing the sutured tendon. HD-AM has already been clinically applied in neurosurgery, ophthalmology, and otolaryngology, and clinical application as an anti-adhesive materials may be achieved in the future.

Prophylaxis for Heterotopic Ossification Following Distal Biceps Tendon Repair.

Heterotopic ossification (HO) is a possible complication of distal biceps tendon repair (DBTR). Several agents can prevent HO formation, although relatively few studies have investigated prophylaxis specifically after DBTR. The purposes of this study were to survey members of the American Shoulder and Elbow Surgeons (ASES) to determine (1) what percentage use HO prophylaxis after DBTR; (2) type, dosage, and duration of prophylaxis used; and (3) use of single-incision or double-incision surgical technique. An anonymous electronic survey was distributed to ASES members to determine the use of HO prophylaxis and DBTR technique. The survey included questions regarding the number of DBTRs performed annually; preferred surgical technique and implants; and type, dosage, and duration of HO prophylaxis used before, during, and after surgery. Descriptive statistics were used to analyze the results. Of 173 respondents, 98 (56.6%) performed 1 to 10 DBTRs per year, 65 (37.6%) performed 11 to 25 DBTRs per year, and 10 (5.8%) performed 26 to 50 DBTRs per year. A total of 131 (75.7%) preferred the single-incision technique, whereas 42 (24.3%) preferred the double-incision technique. A total of 94 (54.3%) performed DBTR using a metal button and interference screw, 35 (20.2%) through drill holes, 25 (14.5%) with suture anchors, and 19 (11.0%) with a metal button alone. A total of 132 (76.3%) respondents did not use HO prophylaxis, and 41 (23.7%) used nonsteroidal anti-inflammatory drugs following surgery. A total of 35 (85.4%) used indomethacin, 18 (51.4%) of whom preferred 75 mg/d for 3 to 4 weeks. Heterotopic ossification is a commonly reported complication following DBTR, especially with the double-incision technique. Prophylaxis with anti-inflammatory medications and suppressive modalities (radiation therapy) appear to reduce the incidence of HO. Despite these data, most surgeons (76.3%) do not use HO prophylaxis. Low annual volume of cases, lack of large-volume studies with outcome data, and the dominant use of the single-incision repair technique may explain this. [Orthopedics. 2021;44(4):e588-e592.].

The relationship of the Phantom® Lapidus Intramedullary Nail System to neurologic and tendinous structures in the foot: An anatomic study.

BACKGROUND: The purpose of our cadaveric study was to determine the proximity of nail insertion and interlocking mechanisms in the Phantom® Lapidus Intramedullary Nail System to neurologic and tendinous structures in the foot. METHODS: We used 10 fresh-frozen human lower-extremity specimen cadavers. For each specimen, the Nail System was inserted as described in the published technique guide. We then performed dissection on the tibialis anterior tendon, extensor hallucis longus tendon, and medial dorsal cutaneous branch of the superficial peroneal nerve and we measured and averaged the distances from each of these structures from the nail. RESULTS: The tibialis anterior tendon was in closest proximity to the insertion of the proximal medial interlock K-wire with an average distance of 0.4mm from the tendon. The extensor hallucis longus tendon was in closest proximity to nail insertion with an average distance of 1.2mm. The medial dorsal cutaneous branch of the superficial peroneal nerve was in closest proximity to the distal interlock K-wire with an average distance of 7.5mm. CONCLUSIONS: The tibialis anterior tendon, extensor hallucis longus tendon, and the medial dorsal cutaneous branch of the superficial peroneal nerve are at risk with the insertion of the nail system. Blunt dissection should be performed using this system with a path to bone before instrumentation to reduce the risk of nerve and tendon injury in the foot.

A Small Amount of Retraction Force Results in Inadvertent Piriformis Muscle Damage During a Piriformis-Sparing Approach to the Hip.

BACKGROUND: Piriformis-sparing approaches to the hip allow surgeons to avoid releasing the piriformis tendon during total hip arthroplasty; however, the consequences of retracting an intact piriformis tendon during such an approach remain ill-defined. The present study aimed to determine the upper limit of force that can be applied during retraction of the piriformis tendon to expose the hip, and to quantify the resultant damage to the piriformis musculotendinous complex. METHODS: A patent-pending instrumented retractor was designed to record the applied force, duration, and angle of retraction during a piriformis-sparing posterior approach to the hip. In addition to the data collected with use of the instrumented retractor, damage to the piriformis muscle and tendon was quantified by a blinded observer. RESULTS: There was no damage to the piriformis tendon in 22 (96%) of 23 hips during piriformis retraction for visualization of the hip capsule; however, there was complete or partial damage to the piriformis muscle at the sacral origin, belly, or musculotendinous junction (i.e., outside the surgical field) noted in 21 (91%) of 23 hips. The mean peak force to failure of the piriformis muscle was exceedingly small (29.0 ± 9.4 N; range, 10.1 to 44.9 N). CONCLUSIONS: The mean peak force applied to the piriformis retractor is much less than the force required for several common daily activities, such as opening a door or crushing an empty aluminum can. Soft-tissue damage that occurs outside the surgical field during the retraction of unreleased muscles, like the piriformis muscle, is common and remains an uncontrolled surgical variable. This inadvertent soft-tissue damage is not routinely accounted for when accessing the invasiveness of a procedure. Hence, it is no longer adequate to define a minimally invasive surgical procedure simply as an approach that involves the limited release of anatomical structures. CLINICAL RELEVANCE: The use of instrumented retractors may redefine surgical invasiveness by providing data that could alter our understanding of the soft-tissue damage caused by retraction and open the possibility of robot-assisted or damage-limiting retractor systems.

Electrospun Nanofibrous Membranes for Preventing Tendon Adhesion.

Tendon injuries are frequent, and surgical interventions toward their treatment might result in significant clinical complications. Pretendinous adhesion results in the disruption of the normal gliding mechanism of a damaged tendon, painful movements, and an increased chance of rerupture in the future. To alleviate postsurgical tendon-sheath adhesions, many investigations have been directed toward the development of repair approaches using electrospun nanofiber scaffolds. Such methods mainly take advantage of nanofibrous membranes (NFMs) as physical barriers to prevent or minimize adhesion of a repaired tendon to its surrounding sheath. In addition, these nanofibers can also locally deliver antiadhesion and anti-inflammatory agents to reduce the risk of tendon adhesion. This article reviews recent advances in the design, fabrication, and characterization of nanofibrous membranes developed to serve as (i) biomimetic tendon sheaths and (ii) physical barriers. Various features of the membranes are discussed to present insights for further development of repair methods suitable for clinical practice.

Ulnar Stump Stabilization Using the Flexor Carpi Ulnaris Tendon for the Rheumatoid Wrist.

Background: The objective of this retrospective study was to evaluate the outcomes of ulnar stump stabilization after ulna head resection using the FCU tendon by investigating the rate of postoperative extensor tendon rupture and click on forearm rotation. Methods: Wrist synovectomy (distal radioulnar joint (DRUJ), radiocarpal and midcarpal joints) and ulnar head resection combined with ulnar stump stabilizing procedure were performed in 58 wrists of 53 patients with RA in our hospital. Before operation, the dorsal subluxation ratio (DSR) of the ulnar head was measured with a multi-slice computed tomography (CT) images. The stabilization of ulnar stump after head resection was performed by the value of the DSR or the instability before the operation. Results: There was neither extensor tendon rupture nor click on forearm rotation in all the patients. Smooth forearm rotation was achieved by ulnar head resection and stabilizing procedure for the ulnar stump. The active range of forearm supination and pronation increased significantly from 68° ± 23° (mean ± SD) to 80° ± 10°, and from 69° ± 17° to 74° ± 13°. The grip power increased from 117 ± 62 mmHg to 185 ± 55 mmHg. In the assessment using 3DCT, the preoperative DSR of 54% improved to 8% on the whole (n = 58). In the wrists with extensor tendon rupture (n = 36), the preoperative DSR of 58% improved to 12%. In the wrists without tendon rupture (n = 22), the preoperative DSR of 46% improved to 2%. Conclusions: The operative technique of ulnar stump stabilization using the FCU tendon was one of the suitable procedure to prevent complications after ulnar head resection.

Percutaneous, Intra-articular, Chevron Osteotomy (PeICO) for the Treatment of Hallux Valgus: A Cadaveric Study.

BACKGROUND: Percutaneous surgery is experiencing sustained growth based on third-generation techniques. This cadaveric study was designed with the main goal of exploring the risk of iatrogenic tendon and neurovascular lesions and defining the safe zones in a percutaneous, intra-articular, chevron osteotomy (PeICO) procedure, as well as assessing the accuracy of the osteotomy itself. METHODS: Eight feet from below-knee fresh-frozen specimens were selected. After the procedure, the specimens were dissected, and structures were inspected for damage. RESULTS: The results of the safety measurements were as follows: (1) distance between portal 1 (P1) and the lateral border of the extensor hallucis longus (EHL) tendon: average 17.6 mm (range 12.7-21.3); (2) distance between P1 and the dorsomedial digital nerve (DMDN): average 7.2 mm (range 1.6-10.4); (3) distance between P1 and the metatarsophalangeal joint: average 15.7 mm (range 9.4-20.5); distance between portal 2 (P2), or the osteosynthesis portal, and the metatarsophalangeal joint: average 25.5 mm (range 22-30.4); distance between P2 and the lateral border of the EHL tendon: average 12.7 mm (range 8-16.7); and distance between P2 and the DMDN: average 4.1 mm (range 1.7-8.2). There were no iatrogenic injuries. The osteotomy angulation in the sagittal plane (reproducibility) average was 85.6 degrees. CONCLUSION: There were no iatrogenic injuries on this cadaveric study of PeICO. CLINICAL RELEVANCE: This study will help orthopedic surgeons understand the risks of performing percutaneous surgery by mimicking an accepted open technique (chevron).

Three-dimensional kinematics of the flexor pollicis longus tendon in relation to the position of the FPL plate and distal radius width.

INTRODUCTION: The standard therapy of intra-articular and extra-articular distal radius fractures consists of open reduction and stabilization using palmar osteosynthesis with an angularly stable plate. The integrity of the flexor pollicis longus tendon (FPLT) may be mechanically affected by the plate, with rupture rates between 1 and 12% reported in the literature, occurring during a postoperative time period from 4 to 120 months. The aim of this study was to investigate the position of the tendon in relation to the distal edge of the plate using high-resolution ultrasonic imaging. MATERIALS AND METHODS: Nineteen patients undergoing osteosynthesis for distal radius fracture in 2015 with the Medartis® APTUS® FPL plate were included in this study. Of these, seven dropped out for various reasons. Therefore,  twelve patients with a median age of 52 years (range 24-82 years) were included in the final analysis. High-frequency ultrasound was performed within a median of 28 (range 10-52) weeks by an experienced radiology specialist to locate the FPLT position in two separate wrist positions: (1) wrist held in 0° position and fingers extended and (2) wrist held in 45° of dorsal extension and actively flexed fingers II to V (functional position). For analysis, we used the axial ultrasound videos. Postoperative X-rays and CT scans were included for the analysis, especially the soft-tissue CT scan window for the exact localization of the FPLT.  Dynamic ultrasound scanning was used to localize the FPLT in relation to the plate in 0° and functional position of the hand. Using CT scanning, the position of the plate relative to the bone was determined. In this way, we were able to correlate the functional FPLT position with the osseous structures of the distal radius. RESULTS: In all cases, the FPLT was positioned closer to the volar distal edge of the FPL plate in functional position than in 0° position. In four cases, the FPLT did not touch the plate at all and was shown to shift diagonally from radio-volar in ulno-dorsal direction during wrist movement from 0° to functional position, similarly to the sliding of the tendon in the assumed physiological motion sequence. In these cases, in the functional position the center of the FPLT was positioned slightly ulnarly of the center of the distal radius (i.e., less than 50% of the distal radius width measured from the radial border of DRUJ), and positioned more ulnarly than in all other cases (i.e., in which the FPLT came into contact with the plate). In the remaining two-thirds of the cases (eight patients), the FPLT touched the plate during wrist movement from 0° to functional position, shifted in dorsal direction and slid into the plate indentation, irrespective of whether the tendon entered the indentation from the radial or the ulnar side, and independent of the ulnoradial position of the plate. No signs of tendinopathy of the FPLT were found in any of the cases. CONCLUSION: The results show that the indentation of the Medartis® APTUS® FPL plate reduces the tendon-plate contact and ideally even prevents it entirely. In particular, ulnar positioning of the plate lowers the risk of tendon-plate contact. If the FPLT touches the plate, the tendon pulls into the plate indentation, thus lowering the contact. Consequently, the Soong criteria are not applicable when a FPL plate is used.

Cadaver study of anatomic landmark identification for placing ankle arthroscopy portals.

BACKGROUND: Arthroscopy-assisted surgery is now widely used at the ankle for osteochondral lesions of the talus, anterior and posterior impingement syndromes, talocrural or subtalar fusion, foreign body removal, and ankle instability. Injuries to the vessels and nerves may occur during these procedures. OBJECTIVE: To determine whether ultrasound topographic identification of vulnerable structures decreased the risk of iatrogenic injuries to vessels, nerves, and tendons and influenced the distance separating vulnerable structures from the arthroscope introduced through four different portals. HYPOTHESIS: Ultrasonography to identify vulnerable structures before or during arthroscopic surgery on the ankle may be useful. MATERIAL AND METHOD: Twenty fresh cadaver ankles from body donations to the anatomy institute in Strasbourg, France, were divided into two equal groups. Preoperative ultrasonography to mark the trajectories of vessels, nerves, and tendons was performed in one group but not in the other. The portals were created using a 4-mm trocar. Each portal was then dissected. The primary evaluation criterion was the presence or absence of injuries to vessels, nerves, and tendons. The secondary evaluation criterion was the distance between these structures and the arthroscope. RESULTS: No tendon injuries occurred with ultrasonography. Without ultrasonography, there were two full-thickness tendon lesions, one to the extensor hallucis longus and the other to the Achilles tendon. Furthermore, with the anterolateral, anteromedial, and posteromedial portals, the distance separating the vessels and nerves from the arthroscope was greater with than without ultrasonography (P=0.041, P=0.005, and P=0.002), respectively; no significant difference was found with the anterior portal. DISCUSSION: Preoperative ultrasound topographic identification decreases the risk of iatrogenic injury to the vessels, nerves, and tendons during ankle arthroscopy and places these structures at a safer distance from the arthroscope. Our hypothesis was confirmed. LEVEL OF EVIDENCE: IV, cadaver study.

Navigation is Equal to Estimation by Eye and Palpation in Preventing Psoas Impingement in THA.

BACKGROUND: Iliopsoas tendon impingement is one possible reason for persistent groin pain and diminished functional outcome after THA. So far, estimation by eye and palpation is the standard procedure to intraoperatively assess the distance of the cup to the anterior rim. However, novel technologies such as imageless navigation enable intraoperative measurements of the cup in relation to the psoas tendon and bony landmarks. QUESTIONS/PURPOSES: We asked whether psoas impingement (1) can be reduced using imageless navigation compared with the standard technique and (2) is associated with specific patient characteristics. Furthermore, we investigated (3) if anterior cup protrusion (overhang) is associated with lower outcome scores for pain and function. METHODS: The current study is a reanalysis of data from a randomized controlled trial evaluating navigation for THA; 135 patients were randomized for surgery with or without the use of imageless navigation. The risk for anterior protrusion of the cup above the acetabular rim and thus potential psoas impingement, defined as an overhang of the cup above the anterior acetabular rim as measured on postoperative CT, was either controlled with the help of navigation or standard control by eye and palpation intraoperatively. Postoperatively, the anterior protrusion of the cup above the acetabular rim was measured on three-dimensional (3-D) CT by a blinded, external institute. In addition to patient-related outcome measures, the Harris hip score, Hip disability and Osteoarthritis Outcome Score, and EuroQol were obtained 1 year postoperatively. Altogether 123 data sets were available for primary analysis and 115 were available for 1-year followup. RESULTS: There was no difference, with the numbers available, between the navigated and the control groups in terms of the mean distance of the cup below the anterosuperior acetabular rim (3.9 mm; -5.3 to 12.6 mm versus 4.4 mm; -7.9 to 13.7 mm; p = 0.72) or the anteroinferior acetabular rim (4.7 mm; -6.2 to 14.8 mm versus 4.2 mm; -7.1 to 16.3 mm; p = 0.29). There was no difference, with the numbers available, in terms of the proportion of cups with anterior overhang (7%, four of 57 versus, 15%, 10 of 66; p = 0.16), respectively. After controlling for potential confounding variables such as cup inclination, cup size, patient age, BMI, stage of arthritis, and length of skin incision, we found cup anteversion (hazard ratio [HR], 0.87; 95% CI, 0.81-0.93; p < 0.001) and female sex (HR, 3.88; 95% CI, 1.01-14.93; p = 0.049) were associated with a propensity to potential psoas impingement. With the numbers available, there were no differences observed in clinical scores between groups with and without anterior cup protrusion. CONCLUSIONS: We found no differences between imageless navigation and estimation by eye and palpation in preventing potential psoas impingement. Despite the comparable clinical outcome for patients with and without cup protrusion, the orthopaedic surgeon should be especially aware of propensity for psoas impingement in women. LEVEL OF EVIDENCE: Level II, therapeutic study.

Brachioradialis Tendon Coverage in Volar Distal Radius Plating.

Volar plate fixation of unstable distal radius fractures has become the preferred technique by most surgeons for the operative treatment of displaced distal radius fractures. Flexor tendon rupture is a rare but serious complication associated with this operation that is thought to be due to irritation of the flexor tendons over the prominent distal edge of the plate. We describe a novel technique of using the brachioradialis tendon to cover the distal edge of the plate to help prevent tendon irritation and rupture.

Proximity of the Triangular Fibrocartilage Complex to Key Surrounding Structures and Safety Assessment of an Arthroscopic Repair Technique: A Cadaveric Study.

PURPOSE: To quantify the distance of the dorsal ulnar sensory branch, floor of the extensor carpi ulnaris (ECU) subsheath, and ulnar neurovascular bundles from the triangular fibrocartilage complex (TFCC), and secondarily to assess the safety of an all-inside arthroscopic repair of the TFCC with a commonly used meniscal repair device with respect to the aforementioned structures. METHODS: A custom K-wire with 1-mm gradation was used to determine the distance of at-risk structures from the periphery of the TFCC in 13 above-elbow human cadaver specimens. An all-inside repair of the TFCC at the location of a Palmer 1B tear was then performed using a commonly employed meniscal repair device. The distance from the deployed devices to the structure in closest proximity was then measured using digital calipers. RESULTS: The mean distance from the deployed device to the nearest structure of concern for iatrogenic injury was 9.4 mm (range, 5-15 mm). The closest structure to iatrogenic injury was usually, but not always, the dorsal ulnar sensory nerve in 9 of 13 wrists (69.2%) at 9.3 mm (range, 5-15 mm); on 3 occasions it was instead the ulnar nerve (23.1%) at 9.5 mm (range, 9-10 mm), and on 1 occasion 6 mm from the flexor digitorum profundus to the little finger (7.7%). Forearm rotation had no significant effect on measured distances (ulnar nerve: P = .98; dorsal sensory: P = .89; ECU: P = .90). The largest influence of forearm rotation was a 0.4-mm difference between pronation and supination with respect to the distance of the TFCC periphery on the ECU subsheath. CONCLUSIONS: An all-inside arthroscopic TFCC repair using a commonly used meniscal repair device appears safe with respect to nearby neurovascular structures and tendons under typical arthroscopic conditions. CLINICAL RELEVANCE: An all-inside arthroscopic TFCC repair using a commonly employed meniscal repair device appears safe in terms of proximity to important structures although further clinical investigation is warranted.

Evaluation of Percutaneous First Annular Pulley Release: Efficacy and Complications in a Perfused Cadaveric Study.

PURPOSE: Trigger finger is the most common entrapment tendinopathy, with a lifetime risk of 2% to 3%. Open surgical release of the flexor tendon sheath is a commonly performed procedure associated with a high rate of success. Despite reported success rates of over 94%, percutaneous trigger finger release (PFTR) remains a controversial procedure because of the risk of iatrogenic digital neurovascular injury. This study aimed to evaluate the safety and efficacy of traditional percutaneous and ultrasound (US)-guided first annular (A1) pulley releases performed on a perfused cadaveric model. METHODS: First annular pulley releases were performed percutaneously using an 18-gauge needle in 155 digits (124 fingers and 31 thumbs) of un-embalmed cadavers with restored perfusion. A total of 45 digits were completed with US guidance and 110 digits were completed without it. Each digit was dissected and assessed regarding the amount of release as well as neurovascular, flexor tendon, and A2 pulley injury. RESULTS: Overall, 114 A1 pulleys were completely released (74%). There were 38 partial releases (24%) and 3 complete misses (2%). No significant flexor tendon injury was seen. Longitudinal scoring of the flexor tendon was found in 35 fingers (23%). There were no lacerations to digital nerves and one ulnar digital artery was partially lacerated (1%) in a middle finger with a partial flexion contracture that prevented appropriate hyperextension. The ultrasound-assisted and blind PTFR techniques had similar complete pulley release and injury rates. CONCLUSIONS: Both traditional and US-assisted percutaneous release of the A1 pulley can be performed for all fingers. Perfusion of cadaver digits enhances surgical simulation and evaluation of PTFR beyond those of previous cadaveric studies. The addition of vascular flow to the digits during percutaneous release allows for Doppler flow assessment of the neurovascular bundle and evaluation of vascular injury. CLINICAL RELEVANCE: Our cadaveric data align with those of published clinical investigations for percutaneous A1 pulley release.

Minimally invasive Akin osteotomy and lateral release: Anatomical structures at risk-A cadaveric study.

BACKGROUND: Among the many surgical techniques used for hallux valgus correction, different osteotomies may be performed in the proximal phalanx as well as lateral release as associated procedures. The aim of this study is to analyze the anatomical relationships and the risks for the soft tissue lessions when performing the dorsomedial minimally invasive surgery (MIS) portal for the Akin osteotomy, and the MIS dorsolateral portal for lateral release, in order to define a safety zone when conducting the procedure in order to avoid complications. MATERIALS AND METHODS: The procedures were carried out on 16 fresh-frozen cadaveric feet. A MIS dorsomedial and dorsolateral portals were performed. The anatomical dissection of the cadaveric pieces was carried out and the different anatomic and surgical relationships were analyzed and measured. RESULTS: No nerve injury was found. Injury of the extensor hallucis longus (EHL) paratendon were seen in 9 cases (56%). There was no injury of the flexor hallucis longus (FHL) tendon and or collateral plantar nerves. A partial injury of the FHL sheath was observed in 44% of the samples. CONCLUSIONS: Although percutaneous Akin osteotomy is clinically effective, the possibility of injury of anatomic structures is high (9-55%), however injuries upon vascular or nerve structures were not seen.

Moderate treadmill running exercise prior to tendon injury enhances wound healing in aging rats.

The effect of exercise on wound healing in aging tendon was tested using a rat moderate treadmill running (MTR) model. The rats were divided into an MTR group that ran on a treadmill for 4 weeks and a control group that remained in cages. After MTR, a window defect was created in the patellar tendons of all rats and wound healing was analyzed. We found that MTR accelerated wound healing by promoting quicker closure of wounds, improving the organization of collagen fibers, and decreasing senescent cells in the wounded tendons when compared to the cage control. MTR also lowered vascularization, increased the numbers of tendon stem/progenitor cells (TSCs) and TSC proliferation than the control. Besides, MTR significantly increased the expression of stem cell markers, OCT-4 and Nanog, and tenocyte genes, Collagen I, Collagen III and tenomodulin, and down-regulated PPAR-γ, Collagen II and Runx-2 (non-tenocyte genes). These findings indicated that moderate exercise enhances healing of injuries in aging tendons through TSC based mechanisms, through which exercise regulates beneficial effects in tendons. This study reveals that appropriate exercise may be used in clinics to enhance tendon healing in aging patients.

The safety of the posterior ankle arthroscopy in management of posterior ankle impingement: A cadaveric study.

BACKGROUND: Arthroscopic management of the posterior ankle impingement with the patient in supine position has the advantage of dealing with anterior ankle pathology at the same time without the need to change position of the patient. This study aims at evaluation of the safety of portal establishment and instrumentation of this technique. METHODS: Sixteen fresh-frozen cadaver specimens were used. The relationships of the posteromedial and posterolateral portals to the adjacent tendons and nerves and the relationship of the coaxial portal tract with the posterior ankle capsule and the flexor hallucis longus tendon were studied. RESULT: Angle θ1 between the intermalleolar line and the posterior ankle coaxial portal tract averaged 1° (-10° to 22°). Angle θ2 between the intermalleolar line and the metal rod where the neurovascular bundle started to move averaged 19° (10° to 30°). Angle θ3 between the intermalleolar line and the metal rod where it reached the lateral border of the Achilles tendon was larger than angle θ2 in all specimens. The angle of safety (θs) averaged 18° (-1° to 26°). CONCLUSIONS: Injury to the tendon, nerves or vessels is possible during establishment of the portals and resection of the os trigonum.

Danger zones for flexor tendons in volar plating of distal radius fractures.

PURPOSE: To define a danger zone for volar plates using magnetic resonance imaging by analyzing the position of the flexor tendons at risk around the watershed line. METHODS: We analyzed 40 wrist magnetic resonance images. The location of the flexor pollicus longus (FPL) and index flexor digitorum profundus (FDPi) tendons was recorded at 3 and 6 mm proximal to the watershed line of the distal radius. We measured the distance between the volar margin of the distal radius and the FPL and FDPi tendons, and the coronal position of the tendons. RESULTS: At a point 3 mm proximal to the watershed line, FPL and FDPi were located on average 2.6 and 2.2 mm anterior to the volar margin of the distal radius. This distance increased to 4.7 and 5.3 mm at a point 6 mm proximal to the watershed line. The FPL and FDPi were located at 57% and 42% of the total width of the distal radius from the sigmoid notch at 3 mm from the watershed, and at 66% and 46% at 6 mm from the watershed. CONCLUSIONS: Surgeons should be aware of the close proximity of the flexor tendons to the volar cortex of the distal radius proximal to the watershed line and their radial to ulnar position. Three millimeters proximal to the watershed line, plate placement more than 2 mm anterior to the volar cortex or the use of plates thicker than 2 mm poses a high risk for directly contacting flexor tendons. CLINICAL RELEVANCE: This article may prove to be helpful in avoiding flexor tendon injury during volar plate fixation.