Expression and Localization of Thrombospondins, Plastin 3, and STIM1 in Different Cartilage Compartments of the Osteoarthritic Varus Knee.

Osteoarthritis (OA) is a multifactorial disease which is characterized by a change in the homeostasis of the extracellular matrix (ECM). The ECM is essential for the function of the articular cartilage and plays an important role in cartilage mechanotransduction. To provide a better understanding of the interaction between the ECM and the actin cytoskeleton, we investigated the localization and expression of the Ca2+-dependent proteins cartilage oligomeric matrix protein (COMP), thrombospondin-1 (TSP-1), plastin 3 (PLS3) and stromal interaction molecule 1 (STIM1). We investigated 16 patients who suffered from varus knee OA and performed a topographical analysis of the cartilage from the medial and lateral compartment of the proximal tibial plateau. In a varus knee, OA is more pronounced in the medial compared to the lateral compartment as a result of an overloading due to the malalignment. We detected a location-dependent staining of PLS3 and STIM1 in the articular cartilage tissue. The staining intensity for both proteins correlated with the degree of cartilage degeneration. The staining intensity of TSP-1 was clearly reduced in the cartilage of the more affected medial compartment, an observation that was confirmed in cartilage extracts by immunoblotting. The total amount of COMP was unchanged; however, slight changes were detected in the localization of the protein. Our results provide novel information on alterations in OA cartilage suggesting that Ca2+-dependent mechanotransduction between the ECM and the actin cytoskeleton might play an essential role in the pathomechanism of OA.

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.

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.

[Management and outcome of type II fractures of the odontoid process]. / Therapiekonzept und Outcome bei Typ-II-Frakturen des Dens axis.

BACKGROUND: The most effective treatment of type II dens fractures according to Anderson and D'Alonzo remains controversial as there is no guidance on the choice of conservative or surgical therapy and if the anterior or the posterior approach is more advantageous. In 1993 Eysel and Roosen showed that the consolidation rate of type II odontoid fractures mostly depends on the morphology of the fracture and established a classification with corresponding treatment recommendations. OBJECTIVE: The investigation aimed at clarifying the outcome of type II dens fractures treated according to the recommendations of Eysel and Roosen. MATERIAL AND METHODS: Data of dens fractures from 72 patients were analyzed and categorized according to the Eysel and Roosen classification. Furthermore, the treatment was analyzed and the outcome was evaluated retrospectively using radiographs acquired during follow-up. RESULTS: The mean age of the 72 patients was 70.7 years. Of the patients 19.4% suffered from type A, 75% from type B and 5.6% from type C fractures according to Eysel and Roosen. Out of the 72 patients 45 were assessed by computed tomography (CT) scan during follow-up. According to the recommendations of the authors 34 of the 41 patients with type A or type B fractures underwent anterior screw fixation of the dens and 3 out of the 4 patients with a type C fracture underwent a dorsal C1 and C2 fusion. After a mean follow-up of 7 months non-union was observed in 15.6% of the patients whereby 6 of the these patients were treated by surgery and 1 patient was managed conservatively. All of the patients who developed a non-union had a type B fracture. CONCLUSION: The simple clinical applicability together with the low rate of non-union development shows that the Eysel and Roosen classification appears to be a suitable guide for clinical use when deciding on the appropriate treatment regimen.

[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.

Biomechanical Comparison of Fixation With a Single Screw Versus Two Kirschner Wires in Distal Chevron Osteotomies of the First Metatarsal: A Cadaver Study.

Distal chevron osteotomy is a common procedure for surgical correction of hallux valgus. Osteosynthesis with 1 screw or 2 Kirschner wires has been commonly used. We compared the stability of the 2 techniques in distal chevron osteotomy. Sixteen first metatarsals from fresh-frozen human cadaver feet (9 different cadaveric specimens) were used. A standardized distal chevron osteotomy was performed. One first metatarsal from each pair was assigned to group 1 (3.5-mm cortical screw; n = 8) and one to group 2 (two 1.6-mm Kirschner wires; n = 8). Using a materials testing machine, the head of the first metatarsals was loaded in 2 different configurations (cantilever and physiologic) in succession. In the cantilever configuration, the relative stiffness of the osteosynthesis compared with intact bone was 59% ± 27% in group 1 and 68% ± 18% in group 2 (p = .50). In the physiologic configuration, it was 38% ± 25% in group 1 and 35% ± 7% in group 2 (p = .75). The failure strength in the cantilever configuration was 187 ± 105 N in group 1 and 259 ± 71 N in group 2 (p = .21). No statistically significant differences were found in stability between the 2 techniques. The use of 1 screw or 2 Kirschner wires had no significant differences in their biomechanical loading capacity for osteosynthesis in distal chevron osteotomies for treatment of hallux valgus.

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.

The femoral neck-shaft angle on plain radiographs: a systematic review.

OBJECTIVE: The femoral neck-shaft angle (NSA) is an important measure for the assessment of the anatomy of the hip and planning of operations. Despite its common use, there remains disagreement concerning the method of measurement and the correction of hip rotation and femoral version of the projected NSA on conventional radiographs. We addressed the following questions: (1) What are the reported values for NSA in normal adult subjects and in osteoarthritis? (2) Is there a difference between non-corrected and rotation-corrected measurements? (3) Which methods are used for measuring the NSA on plain radiographs? (4) What could be learned from an analysis of the intra- and interobserver reliability? MATERIAL AND METHODS: A systematic literature search was performed including 26 publications reporting the measurement of the NSA on conventional radiographs. RESULTS: The mean NSA of healthy adults (5,089 hips) was 128.8° (98-180°) and 131.5° (115-155°) in patients with osteoarthritis (1230 hips). The mean NSA was 128.5° (127-130.5°) for the rotation-corrected and 129.5° (119.6-151°) for the non-corrected measurements. CONCLUSION: Our data showed a high variance of the reported neck-shaft angles. Notably, we identified the inconsistency of the published methods of measurement as a central issue. The reported effect of rotation-correction cannot be reliably verified.

The neck shaft angle: CT reference values of 800 adult hips.

OBJECTIVE: A precise understanding of the radiological anatomy and biomechanics as well as reliable reference values of the hip are essential. The primary goal of this study was to provide reference values of the neck-shaft angle (NSA) for adult patients based on the analysis of rotation corrected computed tomography (CT) scans of 800 hips. The secondary aim was to compare these measurements with simulated anteroposterior roentgenograms of the pelvis. MATERIALS AND METHODS: Pelvic CT scans of 400 patients (54.3 years, range 18-100 years; 200 female) were reconstructed in the derotated coronal plane of the proximal femur and as CT-based simulated anteroposterior roentgenograms of the pelvis in the anterior pelvic plane. Femora were categorized as coxa vara (<120°), physiologic (≥120° to <135°), and coxa valga (≥135°). Intra- and inter-rater reliability were analyzed. RESULTS: Primary research question: Mean NSA for male adults was 129.6° (range 113.2°-148.2°; SD 5.9°) and 131.9° (range 107.1°-151.9°; SD 6.8°) for females in derotated coronal reconstructions. Age (p < 0.001 in both views) and sex influenced the NSA significantly (p = 0.002 and p < 0.001); no significant differences were found between sides (p = 0.722 and p = 0.955). Overall, an excellent reliability of repeated measurements of one or two observers was found (ICC 0.891-0.995). Secondary research question: NSA values measured in the simulated anteroposterior roentgenogram and the rotation corrected coronal reconstruction differed significantly (p < 0.001). CONCLUSIONS: While anteroposterior pelvis radiographs are susceptible to rotational errors, the coronal reconstruction of the proximal femur in the femoral neck plane allows the correct measurement of the NSA.

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 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.

Shoulder arthroplasty in Germany: 2005-2012.

INTRODUCTION: The field of shoulder endoprothetics has undergone a rapid development in the last years. The purpose of the study was to provide an overview of the development of shoulder arthroplasties in Germany from 2005 until 2012. This study hypothesized that the surgical procedures of the shoulder joint is still increasing and have not reached a plateau until 2012. METHODS: Data of the German federal statistical office from 2005 until 2012 were analyzed to quantify hemiarthroplasty, anatomic total shoulder and reversed total shoulder arthroplasty rates depending on age, gender and main coded indications. Procedure codes and diagnosis were analyzed for each year. Comparative analyses were used to visualize the difference between the types of shoulder endoprostheses. RESULTS: A total number of 139.272 shoulder arthroplasties were performed between 2005 and 2012. Total should arthroplasties have increased continuously until 2009. In 2009 more total shoulder arthroplasties have been performed than hemiprothesis implantations, which have culminated in 2008. All in all, women have been treated 3-fold higher than men regarding hemiarthroplasty, total shoulder arthroplasties or reversed total shoulder arthroplasties. Under the age of 60 years the majority of treated patients were male. CONCLUSION: Since 2005 shoulder arthroplasties are still increasing in Germany, whereas a slight reduction could be detected for shoulder hemiarthroplasty from 2009 up until 2012. Meanwhile total shoulder arthroplasties and reversed total shoulder arthroplasties are still increasing. Women have experienced a 3-fold higher hemiarthroplasty, total shoulder and reversed shoulder arthroplasties than men except for individual younger than 60 years.

Mallet finger: a simulation and analysis of hyperflexion versus hyperextension injuries.

The goal of this study was to simulate the mechanisms of hyperflexion and hyperextension injuries of the distal interphalangeal (DIP) joint of the hand and to analyze the resulting extensor tendon injury patterns. The hypotheses were raised that hyperflexion trauma leads to a plastic deformation of the extensor tendon aponeurosis, with or without a small bony avulsion fragment but without joint surface involvement, and that hyperextension injuries can create a shear fracture of the dorsal lip of the distal phalanx, without injury to the extensor tendon aponeurosis. Loading was applied with a swinging pendulum impacting the distal phalanx in 103 human specimens in either an extended or flexion position. After loading, injury patterns were analyzed radiologically and histologically. There was evidence that hyperflexion trauma leads to a plastic deformation or rupture of the extensor tendon. Bony tendon avulsion was evident in 12.2 % of cases. With hyperextension, the extensor tendon remained intact in all cases, but there were large fracture fragments involving the articular surface in 4.1 % of cases. The results of the study show that force on the flexed joint leads to overstretching of the extensor tendon, and to an associated dorsal bony avulsion with intact joint line. Force applied to the joint in extension can lead to a bony dorsal edge fracture with articular involvement and with it, a palmar DIP joint capsule rupture. The results illuminate a direct correlation between the mechanism of injury and the pattern of injury in the clinical picture of mallet finger.

Graft diameter does not influence primary stability of ulnar collateral ligament reconstruction of the elbow.

BACKGROUND: Ulnar collateral ligament insufficiency may result in medial elbow pain, instability, and reduced athletic performance in throwing athletes. Several reconstruction methods have been described, but biomechanical studies suggest that in general, stability of the graft construct is inferior to the native ulnar collateral ligament. This study investigates whether a stronger graft would yield greater resistance to valgus load over the range of motion. METHODS: Ten cadaveric elbows were mounted to a testing fixture and incremental valgus moments of 2.5, 5, and 7.5 Nm were applied with the elbow in 120°, 90°, 60°, 30° and 0° of flexion and in varying rotational forearm positions. The intact and the ulnar collateral ligament released elbow joint were compared with the docking ulnar collateral ligament reconstruction technique, using different graft sources with increasing cross-sectional areas: palmaris longus, tricpes brachii, extensor carpi radialis longus, and semitendinosus. The resulting angular displacement was evaluated and compared between graft sources and different elbow positions. RESULTS: Compared with the intact situation, ulnar collateral ligament release resulted in a significant increase in valgus deformation over the entire range of flexion-extension motion. Ligament reconstruction using any graft source significantly restored valgus stability at 60°, 90°, and 120°, while at 0° and 30°, angular valgus deformation did not significantly differ from the ulnar collateral ligament deficient situation. There were no significant differences in angular valgus deformation between the graft sources over the range of flexion motion or forearm rotation. CONCLUSIONS: This study did not prove that a thicker graft yielded more resistance to valgus moments when using the docking technique. Thicker grafts require larger bone tunnels, cannot be adequately tensioned, and are non-anatomic. Therefore, the palmaris longus or a triceps tendon strip are considered more appropriate for ulnar collateral ligament reconstruction.

Distal radius: anatomical morphometric gender characteristics. Do anatomical pre-shaped plates pay attention on it?

INTRODUCTION: The purpose of the study was to investigate differences in the osseous structure anatomy of male and female distal radii. METHODS: Morphometric data were obtained of 49 distal human cadaveric radii. An imprint of the distal edge was attained using silicone mass and the palmar cortical angle (PCA) of the lateral and intermediate column, here declared as medial, according to the concept of Rikli and Rigazzoni. The lateral and medial length and five widths were digitally measured by three observers. In order to compare the measurements an unpaired t test was used. To prove the reliability of the measurements an intraclass correlation analyses was done. RESULTS: Overall mean medial PCA was 148.25° (SD ± 6.83) and mean lateral PCA 156.07° (SD ± 7.00). In male specimens, the mean medial PCA was 147.38° (SD ± 6.01) and mean lateral PCA was 153.6° (SD ± 6.20) whereas in female specimens, the mean medial PCA was 149.41° (SD ± 7.79) and the mean lateral PCA 159.37° (SD ± 6.78), with statistical significance for the female lateral PCA. No gender significant difference for the medial PCA and no significant side difference for the PCA's could be found. The ICC of the observers was r = 0.936 and 0.976 for the medial and for lateral PCA 0.957-0.984. The palmar cortical length of the distal radius was significantly longer in male specimens. For all widths, larger values for male radii were measured, being statistically significant in all cases. CONCLUSION: Male dimensions concerning the wide were significantly larger when compared with females. Regarding the PCA at the medial and lateral column, we found significant difference for lateral PCA concerning the gender. Overall, study results demonstrated an angle of 148.25° ± 6.83 for the medial PCA and 156.07° ± 7.00 for the lateral PCA.

Endoscopically assisted release of the superficial radial nerve.

INTRODUCTION: The feasibility of endoscopically assisted decompression of the superficial radial nerve at the midportion and distal forearm was assessed. SURGICAL TECHNIQUE: After a 3 cm longitudinal skin incision at the Tinel's sign at the forearm, the subcutaneous tissue is dissected until forearm fascia is detected. The fascia is opened cautiously under direct visualization and the superficial radial nerve is identified. Blunt forceps mobilize the subcutaneous tissue upon the fascia before the illuminated speculum is inserted. Then further dissection of the fascia is performed proximally using the Metzenbaum scissors. After further blunt tunneling by forceps the endoscope is introduced proximally in order to release the superficial radial nerve completely. Then the speculum is inserted distally to identify the nerve within the subcutaneous tissue. Then further visualization is facilitated using the endoscope. CONCLUSION: The endoscopically assisted release of the superficial radial nerve may be feasible in a safe and sufficient way.

Evaluation of efficacy of a new hybrid fusion device: a randomized, two-centre controlled trial.

BACKGROUND: The 360° fusion of lumbar segments is a common and well-researched therapy to treat various diseases of the spine. But it changes the biomechanics of the spine and may cause adjacent segment disease (ASD). Among the many techniques developed to avoid this complication, one appears promising. It combines a rigid fusion with a flexible pedicle screw system (hybrid instrumentation, "topping off"). However, its clinical significance is still uncertain due to the lack of conclusive data. METHODS/DESIGN: The study is a randomized, therapy-controlled, two-centre trial conducted in a clinical setting at two university hospitals. If they meet the criteria, outpatients presenting with degenerative disc disease, facet joint arthrosis or spondylolisthesis will be included in the study and randomized into two groups: a control group undergoing conventional fusion surgery (PLIF - posterior lumbar intervertebral fusion), and an intervention group undergoing fusion surgery using a new flexible pedicle screw system (PLIF + "topping off"), which was brought on the market in 2013. Follow-up examination will take place immediately after surgery, after 6 weeks and after 6, 12, 24 and 36 months. An ongoing assessment will be performed every year.Outcome measurements will include quality of life and pain assessments using validated questionnaires (ODI - Ostwestry Disability Index, SF-36™ - Short Form Health Survey 36, COMI - Core Outcome Measure Index). In addition, clinical and radiologic ASD, sagittal balance parameters and duration of work disability will be assessed. Inpatient and 6-month mortality, surgery-related data (e.g., intraoperative complications, blood loss, length of incision, surgical duration), postoperative complications (e.g. implant failure), adverse events, and serious adverse events will be monitored and documented throughout the study. DISCUSSION: New hybrid "topping off" systems might improve the outcome of lumbar spine fusion. But to date, there is a serious lack of and a great need of convincing data on safety or efficacy, including benefits and harms to the patients, of these systems. Health care providers are particularly interested in such data as these implants are much more expensive than conventional implants. In such a case, randomized clinical trials are the best way to evaluate benefits and risks. TRIAL REGISTRATION: NCT01852526.

Anatomical transosseous fixation of the deep and superficial fibers of the radioulnar ligaments.

INTRODUCTION: The triangular fibrocartilage complex is in conjunction with the interosseous membrane the most important stabilizer of the distal radioulnar joint. Lesions of the triangular fibrocartilage complex may cause instability of the distal radioulnar joint with serious consequences. Therefore, the goal is to reconstruct and provide stability to prevent further harm. SURGICAL TECHNIQUE: Based on the anatomical configuration of the radioulnar ligaments, we present a technique which addresses both the deep and the superficial fibers of the radioulnar ligaments. This surgical procedure can be performed either openly or arthroscopically assisted. Two osseous 2-mm tunnels starting from the ulnar neck to the foveal surface are created. A nonabsorbable suture is passed through the tunnels and the triangular fibrocartilage using a 20-gauge venipuncture needle in order to attach the deep fibers. Then a third osseous tunnel starting from the lateral base of the styloid process to the medial aspect is created. The suture is passed through this tunnel and through the triangular fibrocartilage and around the styloid process palmarily using the same needle as before in order to anchor the superficial fibers anatomically. After reducing the ulna head the sutures are tightened. CONCLUSION: This technique is quite simple and addresses the anatomical configuration of the radioulnar ligaments.

Functionality of middle-aged women after resection-interposition arthroplasty of the trapeziometacarpal joint in comparison to a healthy control group.

INTRODUCTION: Trapeziometacarpal joint osteoarthritis is a very common degenerative joint disease which affects especially women between their fifth and sixth decade of life. To determine the final pinch, grip and functional outcome after trapeziometacarpal arthroplasty and to compare to non-arthritic controls, we hypothesized that patients after the former surgery are expected to have lower grip and pinch strength and a higher DASH score. MATERIALS AND METHODS: 44 women (range 50-65 years of age; median 57 years of age) were examined after resection-interposition arthroplasty because of trapeziometacarpal joint osteoarthritis Eaton-Littler stage 3 and 4 with a minimum follow-up time of 12 months (range 12-99 months; median 47 months) using DASH questionnaire and grip and pinch strength evaluation. The control group consisted of 107 healthy age-matched controls (range 50-64 years of age; median 54 years of age). Differences between both groups were statistically analysed using analysis of covariance. RESULTS: A significant loss of pinch strength and a significant higher DASH score were detected for the patient group in comparison to the controls, whereas grip strength did not differ significantly. CONCLUSIONS: A loss of pinch strength in conjunction with a higher DASH score was detected. The expected loss of pinch strength in conjunction with a reduced physical functionality should be discussed preoperatively with the patient to meet the expectations and to offer the best suitable treatment option.

Anatomical fit of seven different palmar distal radius plates.

INTRODUCTION: The purpose of this study was to compare the anatomical fit of different, precontoured palmar distal radius plates. METHODS: The anatomical fit of seven different types of palmar distal radius plates [Königsee variable fixed-angle radius plate 7/3-hole, Königsee variable fixed-angle radius plate 5/3-hole (Allendorf, Germany), Medartis 2.5 Adaptive TriLock, Medartis 2.5 TriLock, Medartis 2.5 TriLock extraarticular, (Basel, Switzerland), Synthes VA-LCP distal two-column-radius, Synthes LCP extraarticular (Bettlach, Switzerland)] were investigated in 25 embalmed human cadaveric radii. An imprint of the space between the well-positioned plate and the distal radius was attained using a silicone mass and the maximum height of the silicone imprint was digitally measured. The mean maximum imprint height was compared between the seven plates using an analysis of variance with repeated measures and Bonferroni correction for multiple comparisons. RESULTS: The mean maximum distance between the plates and the radial cortex was <2 mm for all plates. The greatest difference was found with the Medartis Adaptive (1.99 ± 0.45 mm) and the least difference with the Synthes two-column (1.56 ± 0.76 mm), this difference being statistically significant (p = 0.005). CONCLUSION: Although there was no complete congruency between the plates and the radial cortex, all distal palmar radius plates investigated in this study presented a reasonable anatomical shape. The Synthes VA-LCP distal two-column-radius plate palmar showed the best anatomical fit. A low profile and optimized anatomical precontouring minimizes irritation of the surrounding soft tissues and should be considered with plate design and implant choice.