Comparison of quantitative flow ratio with instantaneous wave-free ratio and resting full-cycle ratio during daily routine in the catheterization laboratory.

BACKGROUND: Quantitative flow ratio (QFR) is a novel, software-based method to evaluate the physiology of coronary lesions. The aim of this study was to compare QFR with the established invasive measurements of coronary blood flow using instantaneous wave-free ratio (iFR) or resting full-cycle ratio (RFR) in daily cathlab routine. METHODS: 102 patients with stable coronary artery disease and a coronary stenosis of 40%-90% were simultaneously assessed with QFR and iFR or RFR. QFR-computation was performed by two certified experts using the appropriate software (QAngio XA 3D 3.2). RESULTS: QFR showed a significant correlation (r = 0.75, p < 0.001) to iFR and RFR. The area under the receiver curve for all measurements was 0.93 (95% confidence interval, 0.87-0.98) for QFR compared to iFR or RFR. QFR based assessment required less time with a median of 501 s (IQR 421-659 s) compared to iFR or RFR which required a median of 734 s to obtain the result (IQR 512-967 s; p < 0.001). The median use of contrast medium was similar with 21 mL (IQR 16-30 mL) for the QFR-based and 22 mL (IQR 15-35 mL) for the iFR- or RFR-based diagnostic. QFR diagnostic required less radiation. The median dose area product for QFR was 307cGycm2 (IQR 151-429 cGycm2 ) compared to 599 cGycm2 (IQR 345-1082 cGycm2 ) for iFR or RFR, p < 0.001. CONCLUSION: QFR measurements of coronary artery blood flow correlate with iFR or RFR measurements and are associated with shorter procedure times and reduced radiation dose.

Long-term preservation of metacarpophalangeal joint function in traumatic defects by metatarsophalangeal osteochondral transplantation.

INTRODUCTION: The integrity of the metacarpophalangeal (MCP) joints is essential for finger and hand function. Preservation of range-of-motion is one of the aims in reconstruction of complex injuries to these joints. Osteochondral transplants have shown to be reliable in reconstruction of various joint defects. This series presents three patients with traumatic injuries to four MCP joints, which were reconstructed by seven avascular osteochondral transplants of metatarsophalangeal (MTP) joints. The joints were examined for radiographic signs of resorption or joint space narrowing, and if this would affect the joints' function in the long term. METHODS: In three patients (40, 45 and 48 years) with complex injuries to their MCP joints (one milling, two saw injuries), four joints were reconstructed by three metatarsal head and four osteochondral transplants of the base of the proximal toe phalanges. Beside the joint itself, various soft tissue defects were reconstructed in each patient. The patients were clinically and radiographically examined after 9, 6, respectively, 7 years. RESULTS: All patients were satisfied with the result without any pain in the MCP joints. Range-of-motion in the four affected joints rated 25, 60, 75, and 80°, DASH scores rated 13, 29, and 17, respectively. None of the patients complained of problems at their feet. Radiographic examination revealed moderate joint space narrowing in one of the four joints. In another patient, localized osteolysis was found around the screws' heads, so that the screws were removed 7 years post-op. CONCLUSIONS: Osteochondral transplants for reconstruction of MCP defects are able to preserve function in severely injured joints even in the long term. Joint space narrowing may occur, which is not accompanied by pain, however. Since localized osteolysis can cause screw head prominence, mid-term radiographic follow-up is necessary to prevent damage to the joint. In the long term, remaining bone stock may be adequate for total joint replacement.

[Arthroplasty of the hand and wrist]. / Endoprothetik an Hand und Handgelenk.

Arthrosis and autoimmune arthritis frequently lead to major impairment of hand function. Primary therapy consists of well- tried conservative treatments and joint preserving surgical options for special indications. In advanced stages silicon spacers remain the gold standard surgical option for replacement of proximal interphalangeal and metacarpophalgeal joints of the fingers. Alternatively, surface replacement prostheses can restore the biomechanical properties of these joints more porperly. In case of the carpometacarpal (CMC) joint of the thumb, arthroplasty is gaining popularity as modern implants show excellent mid-term outcome. Although current forth generation implants for wrist replacement are promising, total wrist arthroplasty is currently reserved for exceptional indications.

Ultrafast transient absorption and solvation of a super-photoacid in acetoneous environments.

The phenomenon of photoacidity, i.e., an increase in acidity by several orders of magnitude upon electronic excitation, is frequently encountered in aromatic alcohols capable of transferring a proton to a suitable acceptor. A promising new class of neutral super-photoacids based on pyranine derivatives has been shown to exhibit pronounced solvatochromic effects. To disclose the underlying mechanisms contributing to excited-state proton transfer (ESPT) and the temporal characteristics of solvation and ESPT, we scrutinize the associated ultrafast dynamics of the strongest photoacid of this class, namely tris(1,1,1,3,3,3-hexafluoropropan-2-yl)8-hydroxypyrene-1,3,6-trisulfonate, in acetoneous environment, thereby finding experimental evidence for ESPT even under these adverse conditions for proton transfer. Juxtaposing results from time-correlated single-photon counting and femtosecond transient absorption measurements combined with a complete decomposition of all signal components, i.e., absorption of ground and excited states as well as stimulated emission, we disclose dynamics of solvation, rotational diffusion, and radiative relaxation processes in acetone and identify the relevant steps of ESPT along with the associated time scales.

[Resection arthroplasty for thumb basal joint arthritis]. / Die Resektionsarthroplastik bei Rhizarthrose.

Due to the crucial role of the thumb for gripping, osteoarthritis of the first carpometacarpal joint leads to a substantial impairment of hand function. There are effective nonoperative and joint-preserving surgical treatment options for early stages of the disease. In advanced cases, after exploiting conservative treatment, carpometacarpal thumb arthrodesis or arthroplasty may be indicated in selected cases but trapeziectomy with or without interposition or suspension constitutes the gold standard surgical procedure. This reliably provides favorable results, irrespective of the technique, with pain relief, good physical function, excellent patient global assessment and low complication rates.

[Fractures of the carpal bones without the scaphoid bone]. / Frakturen der Handwurzel ohne Os scaphoideum.

With the exception of the relatively frequent fractures of the scaphoid bone, isolated fractures of individual carpal bones are rare. Because these injuries are uncommon and because of the complex anatomy and function of the carpus, treatment of carpal bone fractures can be challenging. Carpal bone fractures generally occur in young, sports active and professional patients, can be easily overlooked in plain radiographs and are frequently associated with ligamentous instability, neurovascular injuries and tendon lesions. Small posttraumatic alterations of the precisely aligned carpal structure can cause chronic pain and functional impairment. Therefore, if a wrist fracture is suspected a thorough clinical examination and appropriate differentiated imaging is always necessary, at the end of which a fracture can be excluded or an appropriate conservative or surgical treatment is initiated, with the aim of restoration of carpal anatomy and function.

[Extensor tendon injuries of fingers in the region of the metacarpophalangeal joint (zone V)]. / Strecksehnenverletzungen der Finger im Bereich der Grundgelenke (Zone V).

Due to the exposed situation of the extension side of the metacarpophalangeal joint when the fingers are bent, injuries in this region are not uncommon. The extensor apparatus lies directly below the skin and the various parts can be easily injured. Due to the complex anatomical structure, the different clinical appearances and the various forms of treatment, injuries of the extensor tendons in the region of the metacarpophalangeal joint must be examined in a very differentiated manner. The not uncommonly occurring deviation phenomenon makes all injuries in zone V suspicious and special attention must be paid to them. The alarming multitude of revision surgeries with tenolysis, arthrolysis and restoration of the balance of extensor tendons or centering show that these operations are much more demanding than the way they are appreciated in the literature and by many surgeons (beginner's operation). The article presents the surgical treatment with suture techniques and reconstruction possibilities as well as the aftercare, in addition to the special anatomy and diagnostics.

Preprocedural valvuloarterial impedance as a predictor of left ventricular ejection fraction improvement after transcatheter aortic valve replacement in patients with reduced left ventricular ejection fraction.

BACKGROUND: Predictors of left ventricular ejection fraction (LVEF) improvement after transcatheter aortic valve replacement (TAVR) in patients with a preoperative reduced LVEF are limited. OBJECTIVES: This study aimed to investigate the relationship between preprocedural valuvuloarterial impedance (ZVa), which represents the global LV afterload, and LVEF improvement after TAVR. METHODS: This was a single-center, retrospective study, which included patients with symptomatic aortic valve stenosis (AS) with a reduced baseline LVEF (< 50%) underwent TAVR. Based on the difference in the LVEF before and 1 month after the procedure, they were divided into two groups: improved group (≥ 10% improvement) and non-improved group (< 10% improvement or worsening). Preprocedural ZVa and clinical outcomes were then compared. ZVa was calculated using preprocedural transthoracic echocardiography data. RESULTS: Among 473 cases of TAVR performed from May 2012 to July 2017 at Queen's Medical Center (Honolulu, HI, USA), 99 patients (improved group, n = 42; mean age 82.0 ± 8.6 years vs. non-improved group, n = 57, mean age 81.4 ± 9.5 years) were included. The improved group had a higher baseline ZVa {4.83 (4.15-6.89) mmHg/ml/m2 vs. 4.04 (3.56-4.63) mmHg/ml/m2, respectively, p = 0.0009} and prevalence of ZVa > 5 mmHg/ml/m2 (45.2% vs. 17.5%, respectively, p = 0.0028). Multivariable analysis of predictors of LVEF improvement ≥ 10% at 1 month identified ZVa > 5 mmHg/ml/m2 [odds ratio (OR): 3.31, 95% confidence interval (CI): 1.05-11.8] as a predictor. The improved group had a lower readmission rate due to heart failure than the non-improved group (log-rank test, p = 0.043). CONCLUSION: In conclusion, Zva is a simple, noninvasive marker that shows promise as a predictor of LVEF improvement after TAVR in reduced LVEF patients.

Long-term functional outcome after dorsal capsular imbrication for post-traumatic dorsal instability of the distal radioulnar joint.

PURPOSE: The goal of this study was the assessment of long-term outcome of dorsal capsular imbrication of the distal radioulnar joint (DRUJ) in dorsal instability. METHODS: The study included ten patients (mean 38.7 years of age) with a mean follow-up time of 11.2 years (9.3 years to 14.3 years). Examination parameters included Disabilities of Arm, Shoulder, and Hand (DASH) questionnaire, modified Mayo Wrist Score (MMWS), determination of range of motion in comparison with the healthy extremity, pre- and post-operative pain level assessment, and examination of DRUJ stability. RESULTS: Eight of ten DRUJs proved to be stable after the above-mentioned follow-up. Mean MMWS was 92.5 (65-100; SD: 11.1). Mean DASH Score was 8.8 (0-60; SD: 18.4). Grip strength reached 93.5% of the contralateral unaffected hand. Range of motion did not differ significantly in comparison with the healthy contralateral extremity. Nine of ten patients regarded pain level reduction as excellent. Eight of ten patients regarded DRUJ stability as excellent after surgery. CONCLUSION: Dorsal capsular imbrication of the DRUJ is an efficacious surgical technique for post-traumatic dorsal instability in the long-term.

Distal radioulnar joint instability: current concepts of treatment.

Distal radioulnar joint (DRUJ) instability is often an underestimated or missed lesion which may entail fatal consequences. The triangular fibrocartilage complex is a biomechanically very important stabilizer of the DRUJ and guarantees unrestricted range of motion of the forearm. To detect DRUJ instability a systematic examination is of uppermost importance. The contralateral healthy arm will be used for comparison during clinical examination. X-rays are required to exclude osseous lesions or deformities. Computed tomography of both wrists in neutral forearm rotation, supination, and pronation may be necessary to verify DRUJ instability in ambiguous situations. Following a systematic clinical examination wrist and DRUJ arthroscopy detects lesions definitely. Tears of the distal radioulnar ligaments which entail DRUJ instability should be repaired preferably anatomically. Ulnar-sided ligament ruptures which cause instability are detected more often than radial-sided ones. Osseous ligament avulsions are mostly refixated osteosynthetically. Ligamentous tears of the distal radioulnar ligaments may be reconstructed using anchor suture or transosseous refixation. Secondary procedures such as tendon transplants are necessary for anatomical reconstruction in cases of unrepairable ligament tears.

[Secondary reconstruction of flexor tendons]. / Sekundäre Wiederherstellung von Beugesehnen.

The secondary reconstruction of flexor tendons is in most cases very demanding and tedious. The indications, selection of the correct surgical procedure, operative technique and further treatment have to be individually adjusted and are mostly very difficult. Due to the previous operations unpleasant surprises may occur intraoperatively, which must be recognized and treated by the surgeon. Nevertheless, a significant improvement of the function of the whole hand can be achieved for most patients, e.g. by a two-stage flexor tendon transplantation or other techniques described in this article.

Correction to: Does increased femoral antetorsion predispose to cartilage lesions of the patellofemoral joint?

Unfortunately, the following reference was not included in the original publication of the article.

Functional outcome after endoscopic assisted release of the ulnar nerve for cubital tunnel syndrome: mid-to-long term results.

AIM OF THE STUDY: The aim of the study was to investigate functional and patient-rated outcome parameters after endoscopic assisted release of the ulnar nerve for cubital tunnel syndrome. METHODS: One hundred of 204 consecutive patients between 2006 and 2011 met the inclusion/exclusion criteria. Fifty-one of these patients were recruited and evaluated clinically and by questionnaire testing retrospectively after a mean follow-up of 82 months (range: 60-116). RESULTS: Neurological parameters (two-point-discrimination, application of Semmes-Weinstein monofilaments, Tinel's test), grip, and three-point pinch strength were not significantly different from the contralateral extremity at the time of examination, whereas key pinch strength was significantly weaker. Mean Disabilities of the Arm, Shoulder, and Hand score was 20.82. Patients' overall opinion was good/excellent for 78% of the study population. DISCUSSION: The examined surgical procedure proved to be as efficacious as open in-situ decompression regarding functional outcome with fewer post-operative complications. Regarding the results it might be postulated that grip strength and three-point pinch strength determination is not necessarily relevant for ulnar nerve evaluation. CONCLUSION: Endoscopic assisted release of the ulnar nerve is a reliable and safe treatment option for cubital tunnel syndrome with satisfactory mid-to-long term functional and patient-rated outcomes.

[Corrective osteotomy of the hand]. / Korrekturosteotomie an der Hand.

Fractures of fingers and metacarpals are among the most frequent injuries. Many fractures can be successfully treated conservatively. Nevertheless, various malformations, such as malrotation, spur development, bone shortening, deviation of the axis and combinations of these individual deformities may appear in the course of time. Corrective osteotomy can correct these deformities with clinically impaired function and improve/optimize hand function. Prerequisites for corrective osteotomy are a precise analysis of the deformity, precise osteotomy, exercise stable osteosynthesis and intensive follow-up treatment of the hand. Complications, such as implant failure, postoperative tendon and joint adhesions, joint contracture and nonunion are however possible.

[Analysis of the accuracy of fit of five anatomically precontoured clavicle plate systems]. / Analyse der Passgenauigkeit fünf anatomisch vorgeformter Klavikulaplattensysteme.

BACKGROUND: A common method in surgical treatment of midshaft clavicular fractures is the clavicle plating system. In addition to traditional osteosynthetic devices, anatomically preformed plate systems also exist. Advantages are described in greater accuracy of fit and less irritation of surrounding soft tissues. The purpose of this study was to compare the anatomical fit of five different precontoured clavicle plating systems. MATERIAL AND METHODS: The anatomical fit of five different types of anatomical precontoured clavicle plates, 3 times VariaxSystem® (Stryker, Kalamazoo, MI), Meves® Plate (Ulrich medical Ulm, Germany) and LCP clavicle plate (Synthes, Bettlach, Switzerland) were investigated in 20 embalmed human cadaveric clavicles. An imprint of the space between the well-positioned plate and the clavicle was obtained using a silicone mass and the silicone imprint was digitally measured. Additionally, the anatomical fit was evaluated by three investigators following a standardized protocol (+2 to -2 points at lateral, midshaft and medial clavicle portions). RESULTS: The first three ranks went to the Stryker Variax-plates. They showed the least distance (Stryker 628027: 7­hole 1.44 mm, low curvature 0.93 mm-2.36 mm, 2. Stryker 628028: 8­hole low curvature 1.68 mm, 1.03 mm-2.4 mm and 3. Stryker 628128: 8­hole high curvature 1.87 mm, range 1.09 mm-3.1 mm) The evaluation of the anatomical fit by the investigators was in agreement with the measurement results. CONCLUSION: Although there was no complete congruency between the plates and the clavicle, all clavicle plates investigated in this study presented a reasonable anatomical shape. The 7­hole VariAx Stryker plate with slight curvature showed the best anatomical fit. A low profile and optimized anatomical precontouring can minimize irritation of the surrounding soft tissues and should be considered in plate design and implant choice.

Does increased femoral antetorsion predispose to cartilage lesions of the patellofemoral joint?

PURPOSE: The purpose of this study was to investigate whether there was a relationship between femoral neck antetorsion and the presence and pattern of osteoarthritis of the patellofemoral joint. It was hypothesized that an increased femoral neck antetorsion (1) correlates with osteoarthritic changes of the lateral facet of the patellofemoral joint and (2) correlates with an increased lateral trochlear height and a decreased sulcus angle. METHODS: Seventy-eight formalin-embedded cadaveric lower extremities from thirty-nine subjects with a median age of 74 years (range 60-88) were used. Surrounding soft tissues of the lower limb were removed. The femoral neck antetorsion was measured and referenced to the transepicondylar axis and the posterior condylar line. The height of the medial and lateral facet of the trochlea and the sulcus angle was measured. The location and the degree of patellofemoral cartilage degeneration were recorded. A Pearson's correlation analysis was performed to correlate the femoral neck antetorsion with the measured knee parameters. RESULTS: No significant correlation could be found between the femoral antetorsion and cartilage degeneration of the lateral patellofemoral joint (n.s.), the height of the lateral trochlea (n.s.) and the sulcus angle (n.s.). CONCLUSION: This study could not document that the femoral neck antetorsion and subsequent internal rotation of the distal femur correlated with the degree of degeneration of the lateral facet of the patellofemoral joint. Clinically, femoral internal rotation may play a minor role in the development of lateral patellofemoral joint degeneration.

Biomechanical comparison of transosseous re-fixation of the deep fibres of the distal radioulnar ligaments versus deep and superficial fibres: a cadaver study.

PURPOSE: We hypothesized that the re-fixation of the deep and superficial fibres of the distal radioulnar ligaments provide improved stability compared to reconstruction of the deep fibres alone. METHODS: Fourteen fresh-frozen cadaver upper extremities were used for biomechanical testing. Transosseous re-fixation of the deep fibres of the distal radioulnar ligaments alone (single mattress suture group; n = 7) was compared to the transosseous re-attachment of the deep and superficial fibres (double mattress suture group; n = 7). Cyclic load application provoked palmar translation of the radius with respect to the rigidly affixed ulna. Creep, stiffness, and hysteresis were obtained from the load-deformation curves, respectively. Testing was done in neutral forearm rotation, 60° pronation, and 60° supination. RESULTS: The re-fixation techniques did not differ significantly regarding the viscoelastic parameters creep, hysteresis, and stiffness. Several significant differences of one cycle to the consecutive one within each re-fixation group could be detected especially for creep and hysteresis. No significant differences between the different forearm positions could be detected for each viscoelastic parameter. CONCLUSIONS: The re-fixation techniques did not differ significantly regarding creep, hysteresis, and stiffness. This means that the additional re-attachment of the superficial fibres may not provide greater stability to the DRUJ. Bearing in mind that the study was a cadaver examination with a limited number of specimens we may suppose that the re-attachment of the superficial fibres seem to be unnecessary. A gradual decline of creep and hysteresis from first to last loading-unloading cycle is to be expected and typical of ligaments which are viscoelastic.

The distal radial decompression osteotomy for ulnar impingement syndrome.

INTRODUCTION: The decompression of the distal radioulnar joint (DRUJ) is performed by ulnar translation of the radial shaft proximal to the sigmoid notch, i.e. detensioning of the distal part of the interosseous membrane (DIOM) while containment of the DRUJ is achieved by closed wedge osteotomy of the radius. The osteotomy shortens the radius which entails detensioning of the triangular fibrocartilage complex (TFCC). SURGICAL TECHNIQUE: Facilitating the modified Henry approach to the distal palmar radius a radial based wedge osteotomy is applied. The proximal osteotomy is proximal to the ulnar head and distal osteotomy is proximal to the sigmoid notch to prevent iatrogenic impingement. Ulnar translation of the radial shaft is performed to loosen the DIOM. The closed wedge osteotomy reduces radial inclination which will foster containment of the DRUJ. CONCLUSION: Distal radial decompression osteotomy of the DRUJ preserves DRUJ function while relieving painful impingement. Further surgical interventions are not compromised in case of failure.

The efficacy of open partial aponeurectomy for recurrent Dupuytren's contracture.

INTRODUCTION: To evaluate the efficacy of open partial aponeurectomy for recurrent Dupuytren's contracture. METHODS: Eighteen patients with recurrent Dupuytren's contracture of 22 fingers were retrospectively assessed with a mean follow-up time of 94 months (range: 70-114 months). Examination parameters included the determination of range of motion (ROM), grip strength, pain and subjective outcome (disabilities of the arm, shoulder and hand (DASH) questionnaire). SURGICAL TECHNIQUE: Dissection with special regard to former skin incision and expected wound defect. Modified incisions after Bruner (Mini-Bruner incisions) were facilitated. Dissection started at the palm. Fibrous tissue was resected proximally within the palm including vertical fibrotic septae. Direct preparation of the neurovascular bundles (NVB) was facilitated from proximal to distal. If the anatomy of the neurovascular structures became unclear around the natatory ligament preparation of the NVB at the distal end of the fibrous cord was performed. After complete preparation of a NVB, dissection was continued from medial to lateral until the other bundle was completely released. Transposition flaps and skin transplants were often used for sufficient wound closure. RESULTS: Recurrence rate was 36 % applying the definition of van Rijssen et al. Fifteen patients had a grip strength of 90 % or higher in comparison to the contralateral side. Ten patients had a pinch strength of 90 % or higher in comparison to the contralateral side. All patients except for one had pain reduction or none postoperatively. Fifteen patients had a DASH score of 15 or lower (range: 0-47). An unrelated ray amputation was suffered due to wound healing complications. CONCLUSIONS: Open partial aponeurectomy performed by a board certified hand surgeon proved to be safe. The postoperative functional outcome seemed to be related to the individual course of the disease.