Intramedullary screw fixation in proximal fifth-metatarsal fractures in sports: clinical and biomechanical analysis

Introduction and purpose: Intramedullary screw fixation (ISF) of proximal fifth-metatarsal fractures is known as first treatment option in young, sports active patients. No study analyzed functional and biomechanical outcome before. Hypothetically ISF leads to (1) a high bony union rate within 12weeks, (2) normal hindfoot eversion strength, and (3) normal gait and plantar pressure distribution. Methods: Fourteen out of 22 patients were available for follow-up with an average follow-up of 42months; clinical and radiological follow-up, and biomechanical evaluation by isometric muscular strength measurement (inversion, eversion strength) and dynamic pedobarography, comparing to the non-affected contralateral foot. Level of significance: 0.05. Results: Subjective result: Excellent or good result in 14 patients, none fair or poor. AOFAS midfoot score: 100 points in 13 patients and 87 points in 1 patient. The same sports activity level (0-4) was reached in 13 out of 14 patients. Radiologic examination: consolidation after 6weeks in 9 patients and after 12weeks in another 4 patients, one partial union. Average maximal eversion strength 59N (ratio to the contralateral foot: 0.92, not significant). Dynamic pedobarography showed ratios of 0.99-1.01 to the contralateral side for ground reaction force, ground peak time, peak pressure and contact area (not significant). Interpretation: A very-high patient-satisfaction, a fast bony healing and complete return to sports were documented. Muscular strength measurement and dynamic pedobarography showed complete functional rehabilitation. Therefore, ISF in proximal fifth-metatarsal fractures can be recommended as a secure procedur

Micro CT analysis of the subarticular bone structure in the area of the talar trochlea

Purpose: Certain regions of the talar trochlea are recognized as exhibiting varying cartilage thickness and degrees of subchondral bone mineralization. These changes have been attributed to the long-term loading history. For the current study, we accepted the hypothesis that stress-induced alterations of the joint surface include not only varying degrees of subchondral lamellar mineralization, but also structural changes of the subarticular cancellous bone. Methods: In order to examine the structure of the subarticular cancellous bone, ten formalin-fixed talar trochleae were analyzed using micro CT. Sixteen measurement zones were defined and then evaluated in five layers each of 1-mm thickness, enabling assessment of the cancellous architecture extending 5mm below the trochlear surface using numerical and structural parameters. Results: As with mineralization patterns in the subchondral lamella, large variation was observed regarding bone volume, trabecular quantity, thickness, and spacing, as well as for structure model index and degree of anisotropy, depending on localization. In addition, like previous reports examining mineralization of the subchondral lamella, two distinct groups could be identified as "bicentric” or "monocentric”. Conclusions: These results show that structural tissue adaptation probably due to loading history is also evident within the subarticular cancellous bon

Autologous matrix-induced chondrogenesis aided reconstruction of a large focal osteochondral lesion of the talus

The aim of this case report is to describe a novel technique for treatment of large osteochondral lesions of the talus using autologous matrix-induced chondrogenesis with a collagen I/III membran

Bony periosteum-covered iliac crest plug transplantation for severe osteochondral lesions of the talus: a modified mosaicplasty procedure

Purpose: This study reports first evidence of a modified procedure for osteochondral autologous transplantation where bony periosteum-covered plugs are harvested at the iliac crest and transplanted into the talar osteochondral lesion. Methods: Thirteen out of 14 patients, average age 39.6 (SD 14.4) years, were followed clinically and radiographically for a median of 25 (24-28) months (minimal follow-up, 24months). Results: For these 13 patients, the American Orthopaedic Foot and Ankle Society hindfoot score increased from 47 (SD 11) points pre-operatively, to 81 (SD 14) points postoperatively (p<0.0001). The average pain score decreased from 6.6 (SD 1.3) points pre-operatively, to 1.4 (SD 1.9) points postoperatively (p<0.0001). Seven patients returned to sports activity. Radiographically good plug osteointegration was observed in nine out of 11 ankles. Follow-up arthroscopy showed fibrous cartilage in four ankles, periosteum hypertrophy in five ankles, and partial or total missing of coverage of the bone in three ankles. Three revision surgeries had to be performed. Conclusions: This modified mosaicplasty might be recommended for severe and recurrent osteochondral lesions of the talus and may lead to restoration of the subchondral bone stock, formation of fibro-cartilage, and stable joint function. Level of evidence: IV

Osteochondrale Läsionen am Talus : anatomische, biomechanische und klinische Analyse

Osteochondrale Läsionen am Talus betreffen in der Regel junge, sportlich sehr aktive Patienten im Alter von 20 bis 40 Jahren. Sie beklagen Schmerzen, Schwellungszustände und Blockaden des Gelenks. Sehr oft liegt eine traumatische Ursache als Folge einer OSG-Distorsion vor. Am häufigsten liegen diese medial oder lateral an der Taluskante. Verschiedene Faktoren sind für die therapeutischen Überlegungen wichtig, die jedoch im einzelnen noch viel zu wenig verstanden sind: (I) Stabilität; die Rekonstruktion muss stabil sein, um einen Krafttransfer zu ermöglichen. Insbesondere auch darum, weil die Läsionen an den Orten der höchsten biomechanischen Belastung liegen. (II) Vitalität; alle avitalen und sklerotischen Areal müssen entfernt und ersetzt werden. Wichtige biologische Informationen zur Vitalität gibt uns das SPECT-CT. (III) Anatomie; das OSG ist das kongruenteste der grossen Gelenke des Menschen. Um ein perfektes Gleiten der beiden Gelenksflächen zu ermöglichen, ist eine optimale anatomische Rekonstruktion notwendig. (IV) Biomechanik des gesamten Gelenks; Um eine möglichst normale Biomechanik des Gelenks wiederherzustellen ist das Adressieren möglicher Co-Faktoren wichtig: Muskeln – Atrophie; Ligamente – Instabilität; Sehnen – Tendinopathie; Gelenk – Synovitis. Das Gelenk ist ein Organ, das über eine Homöostase in einer fein regulierten Balance gehalten wird. Dieser Faktor wurde in einem Modell adressiert, welches den Einfluss einer Muskelatrophie auf andere für die Gelenkhomöostase wichtige Gewebe untersuchte, und das Zusammenspiel und die Abhängigkeit der einzelnen biomechanischen Faktoren aufzeigen konnte. Basierend auf diesen vier Faktoren wurden vier unabhängige Studien durchgeführt, die jeweils einen Aspekt dieser Faktoren adressierten und isoliert publiziert wurden. Mineralisationsdichte und Penetrationskraft der subchondralen Knochenplatte des Talusdoms: hohe Korrelation und spezifische Verteilungsmuster Mit der CT Osteoabsorptionsmetrie (CT-OAM) wurde bei 10 Leichensprunggelenken die Mineralisationsdichte und die Penetrationskraft der subchondralen Knocenplatte gemessen. Dabei zeigten sich zwei Verteilungsmuster: Bizentrisches Maximum (anteromedial und anterolateral), 60%; monozentrisches Maximum (anteromedial oder anterolateral), 40%. Es gab eine sehr hohe Korrelation zwischen beiden Messmethoden. Mit dem CT-OAM können biomechanische Eigenschaften der subchondralen Knochenplatte dargestellt werden. SPECT-CT: eine neue Bildgebung bei osteochondralen Läsionen des Talus Von 25 Patienten wurden MRI, SPECT-CT und die Kombination von beidem von drei unabhängigen Beurteilern hinsichtlich Eigenschaften der Bilder und daraus resultierender Therapiewahl evaluiert. Die Therapiewahl alleine änderte mit dem SPECT-CT in 48% zum MRI und in 52% von SPECT-CT und MRI im Vergleich zum MRI alleine. Die genaue Bedeutung dieser veränderten Therapiewahl muss in weiteren Studien untersucht werden. Radiologische Evaluation der frontalen Talusanatomie in Hinblick auf osteochondrale Transplantationen Anhand von 81 Röntgenbildern ohne Pathologie wurden die Winkel und Radii zwischen den einzelnen Gelenksflächen des Talus in der frontalen Aufsicht ausgemessen. Es konnte keine Korrelation zwischen Winkeln und Radii gefunden werden. Insbesondere zeigt sich ein relevanter Unterschied zwischen medialer und lateraler Taluskante. Diese Werte müssen adressiert werden bei der Rekonstruktion osteochondraler Läsionen. Veränderter Zellmetabolismus von verschiedenen Geweben aus dem Kniegelenk im Kaninchenmodell bei mit Botox A induzierter Quadrizepsmuskelatrophie Während sechs Monaten wurde bei 6 Kaninchen eine Quadricepsmuskelatrophie mit Botox A induziert. Muskelkraftverlust und Histologie des Quadriceps wurden gemessen und dazu mit dem RNA-Zellmetabolismus (totaler RNA Level und spezifische mRNA Level) von Patellarsehne, medialem und lateralem Seitenband und medialem und lateralem Meniskus verglichen. Es zeigte sich, dass ein neuer Steady State erreicht wurde, bei dem sowohl anabole wie katabole Faktoren downreguliert wurden bei unveränderter Gesamt-RNA-Aktivität

Functional limitations after lateral column lengthening osteotomy of the calcaneus are associated with lower quality of life

The purpose of this study was to quantify limitations in sagittal ankle range of motion (ROM) at least two years after lateral column lengthening osteotomy of the calcaneus (LLC) and their implications regarding quality of life.; Fifteen patients with a mean follow-up of 80 ± 27 months after LLC and 15 age-matched healthy persons participated in this study. Ankle joint complex ROM in plantarflexion and dorsiflexion was measured bilaterally using a goniometer and fluoroscopy (patients only). Quality of life was assessed using the short-form health questionnaire (SF36). Differences in ROM parameters (for the tibiotalar and subtalar joint) between sides (affected vs. unaffected) and between groups (patient vs. controls) and the relationship between ROM parameters and quality of life scores were assessed.; ROM of the ankle joint complex on the affected side in patients was smaller than on the contralateral side (goniometer and fluoroscopy) and in healthy persons (goniometer; all P < .05). Among patients, SF36 total and pain scores, respectively, correlated with ROM of the subtalar joint (fluoroscopy; R = 0.379, P = 0.039 and R = 0.537, P = 0.001). Among patients and healthy persons, those with smaller dorsiflexion (goniometer) had lower quality of life scores.; The smaller sagittal ROM of the affected ankle joint complex compared with the contralateral foot and healthy controls was mainly explained by limitations in the tibiotalar joint. Because of its association with quality of life, ROM should be considered in the treatment and rehabilitation planning in patients who are candidates for LLC

Mineral density and penetration strength of the subchondral bone plate of the talar dome : high correlation and specific distribution patterns

The subchondral bone plate plays an important role in stabilizing the osteochondral joint unit and in the pathomechanism of osteochondral lesions and osteoarthritis. The objective of the present study was to measure the mineral density distribution and subchondral bone plate penetration strength of the talar dome joint facet to display and compare the specific distribution patterns. Ten cadaver specimens were used for computed tomography (CT) scans, from which densitograms were derived using CT-osteoabsorptiometry, and for mechanical indentation testing from which the penetration strength was obtained. Our results showed 2 different distribution patterns for mineral density and penetration strength. Of the 10 specimens, 6 (60%) showed bicentric maxima (anteromedially and anterolaterally), and 4 (40%) showed a monocentric maximum (either anteromedially or anterolaterally). A highly significant correlation (p > .0001) for both methods confirmed that the mineral density relied on local load characteristics. In conclusion, the biomechanical properties of the subchondral bone plate of the talar dome joint facet showed specific distribution patterns. CT-osteoabsorptiometry is a reliable method to display the mineral density distribution noninvasively. We recommend CT-osteoabsorptiometry for noninvasive analysis of the biomechanical properties of the subchondral bone plate in osteochondral joint reconstruction and the prevention and treatment of osteoarthritis and osteochondral lesions

Distinctive pain course during first year after total ankle arthroplasty : a prospective, observational study

Patients and health care professionals alike are often surprised by the course of pain after total ankle arthroplasty (TAA). The current study aimed to determine the baseline patterns of postoperative symptoms during the first year following uncomplicated TAA

Intra- and inter-observer reliability of a new standardized diagnostic method using SPECT/CT in patients with osteochondral lesions of the ankle joint

Single Photon Emission Computed Tomography-Computed Tomography (SPECT/CT) gains an important part of diagnostics in patients with osteochondral lesions (OCL). SPECT/CT is a hybrid imaging modality, which combines a 3D scintigraphy (SPECT) and computerized tomography (CT) into one single procedure and combines metabolic data, structural and mechanical information. The purpose of the study was to develop and evaluate a standardized method to anatomically localize and quantitatively analyze the bone SPECT tracer activity of the ankle joint using SPECT/CT.; OCL on the talus were diagnosed in 16 patients by 99mTc-HDP-SPECT/CT and MRI by specialized orthopedic surgeons and radiologists and retrospectively included. The articular superior surface of the talus was subdivided in six anatomical regions (T1-T6). Using customized software, absolute bone SPECT values for each anatomical area were analyzed. Relative bone tracer uptake was calculated in relation to specific reference regions representing bone SPECT tracer background activity. All measurements were performed twice by two independent observers, blinded to clinical information. Intraclass correlation coefficients (ICC) were calculated for inter- and intra-observer reliability. The intraclass correlation coefficients (ICC) showed an excellent inter- and intra-observer reliability.; The intraclass correlation coefficients (ICC) of all six regions are between 1.00 and 0.84 which is defined as very good. Results from region T1 to T6 impair slightly due to measurement regime. All ICCs of observer 1 were nearly the same as the results of observer 2 in all regions.; The presented standardized SPECT/CT algorithm is clinically feasible and showed high inter- and intra-observer reliability. It might help to better understand the complex pathology of OCL on the talar dome. The major potential benefit of SPECT/CT is the assessment of the subchondral bone plate and the subchondral bone

A novel imaging method for osteochondral lesions of the talus--comparison of SPECT-CT with MRI

Magnetic resonance imaging (MRI) is the current standard in noninvasive diagnostics of osteochondral lesions (OCLs) of the talus. Single-photon emission computed tomography-computed tomography (SPECT-CT) is a new technique that displays different imaging qualities. The influence of the aforementioned diagnostic information on treatment decision making in talar OCLs is not known