Intraoperative 3D-Bildgebung am Handgelenk mit einem mobilen isozentrischen C-Bogen

In addition to conventional radiological C-arm image amplifiers used for intraoperative imaging, now a new mobile C-arm image amplifier with an option for three dimensional imaging (Iso-C 3D) is available to visualize reduction of fractures and position of implants. In a wrist-model three titanium pins were placed and three holes of different length were drilled. Distances between the pins and the depths of the drilled holes were calculated in conventional computer tomographic scans and Iso-C 3D scans in perpendicular, 30 degree and 90 degree position of the gantry and compared to actual distances and depths. There were no significant differences between the actual measured distances and those measured by CT scans and Iso-C 3D scans. Furthermore, gantry position had no significant effect upon the results. Iso-C 3D scans are as reliable as conventional CT scans for intraoperative controlling of implant positioning.

Kahnbeinfrakturen - wann operativ, wann konservativ? CT-basierte Klassifikation

Traditionally acute scaphoid fractures were treated by immobilization. As a consequence we have to deal with a high number of scaphoid non-unions or SNAC wrists. A study of 30 patients with scaphoid non-union showed that only 30% (9 patients) have not seen a doctor, while the majority of the patients (70%, 21 patients) were treated by a physician after trauma. In 15 (71.4%) of these 21 patients a missed diagnosis and in 6 (28.6%) a failed conservative treatment of the scaphoid fracture were the reasons for scaphoid non-union. Therefore, improvements in the diagnosis and therapy of scaphoid fractures are urgently needed. Herbert's classification of scaphoid fractures provides the underlying rationale for treatment according to the fracture type seen on X-ray. Differentiation between stable and unstable fractures sometimes is difficult from conventional X-rays. In these cases we recommend a CT bone scan in the long axis of the scaphoid. According to the CT scan we modified Herbert's classification: undisplaced waist fractures are classified as stable and can be treated conservatively or can be stabilized percutaneously using minimally invasive procedures. Comminuted or displaced fractures are classified as unstable and need operative treatment because of the increased risk of scaphoid non-union after plaster immobilization. Fractures of the proximal pole of the scaphoid should be treated operatively by internal fixation, even if they are not displaced, because of the reduced perfusion. We recommend a CT scan of the scaphoid, if there is any doubt about the diagnosis or the stability of the scaphoid fracture. In any case, a CT scan has to be ordered to justify a conservative treatment.

[Bilateral carpal tunnel syndrome with familial accumulation]

We report on a six-year-old girl with bilateral carpal tunnel syndrome with familial accumulation. Parents and one grandmother had positive history for CTS, treated by surgical decompression. Following neurologic and radiologic evaluation and after failed conservative treatment in a plaster cast, open carpal tunnel release was performed in a two-stage procedure. Postoperatively symptoms diminished and now six months after surgery, all complaints disappeared completely.

Die Kraftübertragung am Handgelenk nach Skaphoid-, Trapezium- und Trapezoideumfusion

Scaphotrapeziotrapezoid (STT) arthrodesis has been proposed to stabilise the radial column and to redirect the load away from the lunate. Midterm effects on force transmission are still unclear. Six patients who were treated with triscaphe arthrodesis were examined after an average of 5 years using CT osteoabsorptiometry of both wrists. STT arthrodesis had been performed in four cases with Kienböck's disease type IIIb and in two cases of scaphotrapeziotrapezoid arthritis. At all contralateral wrists peak mineralisations were found beyond the lunate fossa and in the scaphoid fossa of the distal radius. At the side with STT arthrodesis there was only one peak. In five cases this density maximum was beyond the scaphoid fossa and in one case half beyond the lunate and half beyond the scaphoid fossa. Triscaphe arthrodesis allows load transmission from the lunate to the radial column.

Handgelenkläsionen in der direkten MR-Arthrographie im Vergleich zur Arthroskopie des Handgelenks

BACKGROUND

Wrist arthroscopy is routinely used for diagnosis of ligamentous lesions to the wrist. Although it is very sensitive and specific, it is also more invasive than other available diagnostic techniques.

METHOD

In a prospective trial, 125 patients (80 men, 45 women) 37 years old (+/- 12) with clinical evidence of wrist lesions were evaluated with direct wrist arthro MRI. Within 24 hours following direct arthro MRI wrist arthroscopy was performed. The surgeons and radiologists were not aware of the other results until completion of their investigation. Specificity, sensitivity, positive predictive value, negative predictive value and accuracy were determined.

RESULTS

According to the MRI findings, lesions of the TFCC were suggested in 70 patients (56 % of all patients). In 65 cases this was confirmed by wrist arthroscopy. In the remaining 55 patients no TFCC lesions were detected by MRI. However in three cases TFCC lesions were found by arthroscopy. In the remaining 52 patients MRI accurately excluded TFCC lesions. There was a correlation of MRI and arthroscopy in detecting TFCC lesions in 93.6 %. Sensitivity was 94 %, specificity 89 %, positive predictive value 91 % and negative predictive value 93 %. Complete scapholunate ligament tears were detected by MRI in 12 (9.6 %) cases. Correlation with wrist arthroscopy was 99 %, sensitivity 92 %, specificity 100 %, positive and negative predictive value 100 % and 99 %, respectively. Accuracy for incomplete scapholunate lesions (n = 17, 13.6 %) and lunotriquetral tears (n = 4, 3.2 %) was poor (sensitivity 59 % and 25 %, specificity 100 % and 99 %).

CONCLUSION

Though sensitivity of MRI arthrography approaches that of arthroscopy, it cannot replace it at the moment. However, it is a potent additional tool for wrist diagnosis if intraarticular contrast is used. It can facilitate diagnosis and indications for surgery of the wrist. It may make arthroscopic and more invasive interventions for diagnostic purposes avoidable in future.

Frühe Ergebnisse der Fingermittelgelenkendoprothetik mit der Pyrocarbonprothese (Ascension®) bei idiopathischen und posttraumatischen Arthrosen

Surgical treatment of painful idiopathic and post-traumatic arthritis with joint replacement of the proximal interphalangeal joint has become increasingly important. Due to shortcomings of former constrained and partially constrained prostheses with regard to abrasion and durability we have been using an unconstrained prosthesis since April 2002. This model is an almost abrasion free, biocompatible 2-component prosthesis. The surface is shaped like the condyles and the position is secured in a press-fit technique. During October 2004 we reviewed the results of 20 out of 29 patients with idiopathic or post-traumatic arthritis who had been treated with a pyrolytic carbon proximal interphalangeal joint prosthesis from April 2002 to April 2004 retrospectively. Clinical, subjective and radiological parameters were studied. On follow-up after 0.5 to 2.5 years the patients were satisfied with the pain relief. The range of motion varied. However, with an average ROM of 50 degree it was equivalent to the results in literature. Signs of periprosthetic cysts, osteophytes and loosening of the proximal as well as of the distal component could be seen in the radiograms of some patients. There was no correlation between these radiological observations and range of motion, pain or grip strength. In three cases the joint prosthesis had to be converted to an arthrodesis of the proximal interphalangeal joint. Bearing in mind the correct indications (intact collateral ligaments, stable bone stock and sufficient extensor and flexor tendons), pyrocarbon prosthesis are a treatment option for idiopathic and posttraumatic arthritis preserving motion and reducing pain. Radiological results seem to indicate an absence of osteointegration and tension forces at the prosthesis/bone interface. Further investigation will be necessary to improve surface and design to increase radiological results in long-term follow-up. Additional surveys are required to improve indications, surgical approach and intraoperative control of correct component positioning.

Zur Differenzialdiagnostik des „signalkompromittierten” Os lunatum in der MR-Tomographie

PURPOSE

To define both the underlying pathology and diagnostic criteria in lunates presenting with conspicuous signal pattern in MRI.

MATERIALS AND METHODS

The retrospective evaluation of 2940 MRI examinations revealed 203 patients with signal alterations of the lunate. All MRI examinations were performed on 1.5-Tesla platforms using dedicated surface coils and an intravenous contrast agent. To establish a definitive diagnosis, a total of 252 MRI examinations (49 follow-ups), 22 CT examinations and 4 arthroscopic studies were obtained in addition to the obligatory conventional radiographs.

RESULTS

Incorporating all clinical data, radiographs and MRI examinations succeeded in assigning a diagnosis in 136 signal-compromised lunates (67.0 %), whereas additional diagnostic procedures or follow-up examinations were required for the definitive diagnosis in 57 cases (33.0 %). The most frequent entities were 51 cases of Kienbock's disease (25.1 %), 47 cases of ulnolunate-(triquetral) impaction syndromes (23.2 %) and 44 cases of intra-osseous ganglion cysts (21.7 %). Other pathologies included 23 degenerative, 19 traumatic and 10 inflammatory changes as well as 9 congenital conditions. For MRI assessment of the altered lunate, the most important parameters were location and morphology as well as involvement of the articular and osseous structures of the carpus.

CONCLUSION

The lunate may be affected by different pathological states of the wrist. In total, only one quarter of the signal-compromised lunate represented Kienboeck's disease.

Special aspects of wrist arthritis management for SLAC and SNAC wrists using midcarpal arthrodesis: results of bilateral operations and conversion to total arthrodesis

Although midcarpal wrist arthrodesis is recognized as a standard procedure to treat scapholuate advanced collapse (SLAC) and scaphoid nonunion advanced collapse (SNAC) of the wrist, little has been reported about patients with bilateral involvement and the number, cause, and results of failed cases requiring conversion to total wrist arthrodesis. This study investigated the results of 20 patients with bilateral procedures and of 22 patients who underwent total wrist fusion after failed midcarpal arthrodesis out of an overall group of 907 patients treated by this method during a 12-year period. Of these, 16 bilateral and 20 converted cases were reexamined after an average of 48 months and 42 months, respectively. Patients after bilateral midcarpal arthrodesis experienced a pain reduction by an average of 54% of the preoperative pain values at rest and by 56% at stress on the visual analog scale (scale range: 0 to 100) and from intolerable (3.7) to pain only during stress (1.9) on the verbal scale (scale range: I to 4). A mean arc of wrist extension and flexion of 53 degrees on the right and 49 of the left wrist was preserved. The mean DASH score was 45 points and 70% of the patients felt impaired only during certain activities. Total arthrodesis reduced pain in 18 of 20 reexamined wrists by 67% of the previous values after the failed partial arthrodesis at rest and by 46% at stress on the visual analog scale andfrom intolerable pain (3.7) to pain only during stress (2.1) on the verbal scale. Seven of the 20 reexamined patients noted complete pain relief at rest and two also under stress conditions. The DASH score averaged 39 points. A mean Krimmer score of 46 points and a mean Buck-Gramcko and Lohman evaluation of 6 points represented a satisfactory result. Grip strength of the operated hand averaged 53% of the opposite side. Subjectively, 30% felt impaired only during certain activities, 55%felt considerably and 15% strongly limited in daily life. However, all but two patients were satisfied with the secondary total wrist fusion as pain was considerably reduced. Midcarpal arthrodesis reliably reduced pain and preserved valuable wrist mobility thus improving daily activity and quality of life also in bilateral carpal collapse. In the rare cases when midcarpal arthrodesis failed, total wrist arthrodesis markedly improved the complaints in most patients, but in contrast to other studies complete pain was seldom.

Palmare winkelstabile Plattenosteosynthese der instabilen distalen Radiusfraktur

Internal fixation of distal radius fractures often shows the problem of secondary dislocation due to dorsal comminution and osteoporosis. Although dorsal plating systems provide good stabilization, the intraoperative control of reduction is difficult in the comminuted area with high incidence for the need of cancellous bone graft. Occurrence of extensor tendon complications including tendonitis and rupture is not uncommon. The use of fixed angle devices by a palmar approach has demonstrated the advantage of better visualization and control at the fracture side. The subchondrale support of the articular surface by fixed angle pegs or screws prevents secondary dislocation allowing early mobilization. Better soft tissue coverage is associated with a low complication rate. 62 patients (average age 55 years) were treated with different fixed angel devices according to the fracture type and underwent retrospective evaluation with mean follow-up of 11 months (6-23 months). According to the AO Classification there were 3 A2, 24 A3, 7 B3, 14 C1, 9 C2 und 5 C3 fractures. The majority beside the B3 types and one C3 fracture were dorsally displaced. All of them showed healing without relevant secondary loss of reduction. Mean DASH score reached 19 points.

[Ulnar head prosthesis]

The ulnar head prosthesis has been the subject of a prospective multicenter-study since 1995. Until 2000, it has been used in 57 patients by the study group. In 35 patients, the indication was painful instability of the distal end of the ulna following previous resection arthroplasties, and in 22 patients it was painful arthritis of the distal radioulnar joint (DRUJ). The mean follow-up was 38 months. Pronation increased from a preoperative mean of 63 degrees to a postoperative value of 78 degrees, while supination increased from 43 degrees to 76 degrees. Grip strength improved from a preoperative mean of 51% to a postoperative mean of 77% of the opposite limb. Pain, measured on the verbal pain scale (1-4), was reduced remarkably from a preoperative mean level of 3.6 to a postoperative mean of 1.7. Patient' satisfaction was evaluated using the visual analog scale (0-10) and improved from a preoperative mean of 2.1 to a postoperative mean of 7.9. With one exception of loosening, we consistently found bony integration of the shaft of the prosthesis. Stability of the DRUJ was achieved in all but three patients. This method has given reliable and excellent results as a salvage procedure for failed resection arthroplasties of the DRUJ with painful instability of the distal end of the ulna. We consider the method an alternative treatment option for the arthritically destroyed DRUJ. Sufficient soft tissue to stabilise the prosthesis is needed to successfully reconstruct the DRUJ.

Minimal invasive treatment for scaphoid fractures using the cannulated herbert screw system

Internal fixation of scaphoid fractures avoids the problems associated with prolonged plaster immobilization and, at the same time, allows an early return to activity for these mostly young patients.Internal fixation of the scaphoid is greatly facilitated by the use of specially designed headless bone screws, such as the Herbert bone screw, originally developed specifically for internal fixation of the scaphoid; furthermore, the advent of cannulated scaphoid screws has made closed (percutaneous fixation) stabilization of the scaphoid a reality. Indeed, this method has now become the treatment of choice for the majority of acute scaphoid fracture, bringing with it all the advantages of internal fixation without the disadvantages of open surgery.However, the success of closed treatment is also dependent on an accurate assessment of the fracture, and for this reason, we now advocate the routine use of computed tomography preoperatively. Because of the complex, 3-dimensional shape of the scaphoid, simple x-rays alone are inadequate, whereas computed tomography, parallel to the long axis of the scaphoid, allows excellent visualization of the fracture and any associated deformity, which must be corrected at the time of surgery.We describe here our method of treating acute scaphoid fractures, and we report the outcome of minimally invasive fixation.

Bildgebende Verfahren am Handgelenk

Injuries of the wrist are difficult to diagnose because of the complex and narrow anatomic structures. Based on precise clinical examination, X-rays, CT, and MRI are valuable additional tools that can be used. If a fracture is suspected a CT scan is preferable. In the case of a suspected soft tissue or ligamentous injury and non-vital fragments or necrosis MRI is suitable. Other diagnostic tools are presently of minor importance for the wrist. Technical innovations allow better visualization and classification of lesions. However, exact knowledge of the tools is important.

Teil-Arthrodesen von Skaphoid, Trapezium und Trapezoideum (STT-Fusion)

BACKGROUND

Scapho-trapezio-trapezoid (STT)/triscaphe fusion is used to stabilize the radial column of the wrist. However the reported results are controversial.

MATERIAL AND METHODS

111 patients were treated with STT fusion from 1992 to 1997. Indications were chronic dissociation of the scapholunate joint (n = 15), idiopathic arthrosis of the scaphotrapeziotrapezoid joint (n = 11), Kienböck's disease in advanced stage (n = 84) and dislocation of the trapezium (n = 1). This study reviews the results after an average follow-up period of four years (range, two to eight years).

RESULTS

Patients showed an average wrist motion (ROM) in extension and flexion of 81 % of the preoperative range and in radial and ulnar deviation of 68 % of the preoperative range. Preoperative pain values (VAS) were reduced 76 % (non-stress) and 55 % (stress). The average grip strength improved to 65 % of the contra-lateral side. Good results were reached according to the modified Mayo wrist score with a score of 66 points (71 points in arthritis of the STT joint; 62 points in Kienböck's disease, 60 points in SL-dissociation). The patients described low disability in the DASH scores, with an average of 27 points.

CONCLUSIONS

Our data show that STT fusion is reliable and effective for treatment and pain relief and offers reasonable functional results in the above mentioned indications.

Der posttraumatische karpale Kollaps

PURPOSE

Midcarpal fusion is a reliable treatment for posttraumatic carpal collapse in the short or midlong term. The long-term results remain, however, unclear. The objective of this study was to assess the long-term clinical outcome but also the incidence of an arthrosis of the radiolunate joint or an ulnar translocation after excision of the scaphoid.

METHOD AND MATERIAL

37 patients after midcarpal fusion were reexamined after an average follow-up of 97 months clinically and radiologically.

RESULTS

The average range of motion from extension to flexion was 62 degrees, the average grip strength changed from 69 % of the opposite side before surgery to 80 % after surgery. Pain in the verbal analogue scale improved from 2.7 preoperatively to 1.7 postoperatively. The Krimmer wrist score was 72, whereas 28 patients (76 %) reached a good or excellent result. The mean DASH score was 24 points. At the X-rays, ten patients (27 %) showed an arthrosis of the radiolunate joint and/or an ulnar translocation. Differences in clinical results between the groups with or without X-ray pathology were not statistically significant. From 107 patients with a midcarpal fusion in the time of interest, seven (6.5 %) had to be converted into wrist arthrodesis because of ongoing pain.

CONCLUSION

Also in the long-term the motion-sparing midcarpal fusion offers a functional advantage over wrist arthrodesis.

[Direct MR arthrography of the wrist in comparison with arthroscopy: a prospective study on 125 patients]

OBJECTIVE

In literature the diagnostic value of MRI for detecting lesions of the carpal ligaments and the TFCC is judged controversially. The aim of the following study is to determine the diagnostic accuracy of direct MR arthrography for depicting and staging of intraarticular lesions of the wrist.

MATERIAL AND METHODS

One day before undergoing arthroscopy, 125 patients suffering from wrist pain were examined with direct MR arthrography in a prospective and blinded study. A mixture of contrast medium (iodine-containing contrast medium and gadopentetate in relation 200 : 1) was injected into both radiocarpal and midcarpal joints. The following sequences were acquired on a 1.5T scanner: coronal T1-weighted SE, coronal fat-saturated T1-weighted SE, coronal T1-/T2*-DESS-3D, and sagittal T2*-weighted MEDIC. MRI results were compared with arthroscopic findings using statistical analysis (SEN = sensitivity, SPE = specificity, PPV = positive predictive value, NPV = negative predictive value, ACC = accuracy).

RESULTS

In comparison to arthroscopy as the accepted diagnostic gold standard, the following results were found for MR arthrography. Detection of TFCC lesions: SEN 97.1 %, SPE 96.4 %, PPV 97.1 %, NPV 96.4 %, ACC 96.8 %. Detection of complete tears of the scapholunate ligament: SEN 91.7 %, SPE 100 %, PPV 100 %, NPV 99.1%, ACC 99.2%. Detection of partial tears: SEN 62.5 %, SPE 100 %, PPV 100 %, NPV 94.8 %, ACC 95.2 %. Detection of cartilage defects: SEN 84.2 %, SPE 96.2 %, PPV 80 %, NPV 97.1 %, ACC 94.4 %. In total, only three lesions of the lunotriquetral ligament were present.

CONCLUSION

Direct MR arthrographic imaging is well suited for detecting intraarticular lesions of the wrist. The presented diagnostic results of MR arthrography are superior to the results of unenhanced MRI reported in the literature. Direct MR arthrography as a reliable diagnostic tool is strongly recommended if lesions of the scapholunate ligament and the triangular fibrocartilage complex are suspected. In contrast, an attitude of caution must be adopted in diagnosing lesions of the articular cartilage of the wrist.

[Standardised operation technique for ulna-shortening with a new sliding-hole plate]

Ulna-shortening is a widely accepted procedure for the treatment of ulna-impaction syndrome. High rates of non-unions however necessitate improving the operation technique. The new device introduced in this study is a 7-hole plate in which two proximal holes are sliding-holes. By correct placement of two distal screws and two screws in the sliding-holes, rotational stability is guaranteed. The osteotomy is performed while the plate is loosely fixed to the ulna. After fixation of the two distal screws, the sliding-holes facilitate reposition with a good closure of the osteotomy gap. Excentric placement of two more screws and placement of a lag screw across the oblique osteotomy leads to further compression at the osteotomy site. Ulna-variance can be adjusted exactly. So far the plate has been implanted in 15 patients. Ulna-variance was reduced from + 2 to - 2.2 mm. The clinical results are comparable to those of ulna-shortenings in the literature. The sliding-hole plate allows an exact connection with good closure of the osteotomy without malrotation. With this simplified technique, the risk of non-union can be reduced.

[Treatment of hand surgery patients in chronic pain]

The treatment of hand surgery patients suffering from chronic pain requires an interdisciplinary procedure. An imbalance between nociception and antinociception can be seen as a reason for the chronification of pain. The complexity of the problem of chronic pain patients is marked by a wide variety of symptoms. Full diagnostic assessment to detect or to exclude other organic diseases is required. Rehabilitation to improve function and reduce pain intensity has priority. Our therapeutic strategy consists of intensive physiotherapy and analgesic drugs as well as a series of blockades with buprenorphine (Temgesic) of the ganglion stellatum (GLOA). This specific therapy achieved an improvement of the function of the upper extremity and a reduction of pain intensity. The majority of patients were satisfied with the outcome.

[TFCC-lesion. MR arthrography vs. arthroscopy of the wrist]

In a blinded study from January to July 2000, 125 patients suffering from specific complaints of the wrist were examined with direct MR arthrography prospectively. Within 24 hours an arthroscopy of the wrist was performed. With the MR arthrography in 70 patients or 56% of all patients injury of the TFCC was diagnosed. In 65 patients this could be verified arthroscopically. In the remaining 55 patients no TFCC lesion was diagnosed with the MR arthrography. However lesions were found via arthroscopy in three cases,were MRI findings expected an intact TFCC. In the remaining 52 cases the MRT could exclude a lesion of the TFCC correctly. An agreement of the MRT and arthroscopic results could be determined in 93.6% of the cases (correlation). The diagnosis of a TFCC lesion by means of MRI was correct in 94% of the cases (sensitivity), the exclusion of such lesion in 89% (specificity). Positive or negative predictive values of 91% or 93% were achieved. Since neither a specificity nor a sensitivity of 100% can be reached at the moment, the MR arthrography cannot replace the arthroscopy. However it could be a potent additional tool for wrist diagnosis if intraarticular contrast is used. It can facilitate the diagnostics and the indication for surgery at the ulnocarpal wrist and help to reduce arthroscopic interventions that are only for diagnostic purposes and without any therapeutic consequences. With improvement of the technique of magnet resonance tomography we can expect further increase of accuracy and the clinical use of the MR arthrography in the diagnostic workup at the ulnocarpal wrist.

[Scapholunate ligament tears in MR arthrography compared with wrist arthroscopy]

In a blinded study from January to July 2000, 125 patients suffering from specific complaints of the wrist were prospectively examined with direct MR arthrography. Within 24 hours an arthroscopy of the wrist was performed. With MR arthrography in 21 patients or 17 % of all patients, injury of the scapho-lunate ligament was diagnosed. In all patients this could be verified arthroscopically. In the remaining 104 patients, no SL-ligament lesions were diagnosed with the MR arthrography. However, partial lesions were found via arthroscopy in seven cases and complete lesions of the ligament were found in one case, where MRI findings expected an intact SL ligament. In the remaining 96 cases, the MRI could correctly exclude a lesion of the SL-ligament. The diagnosis of a SL-ligament lesion by means of MRI was correct in 100 % of the cases (specificity), the exclusion of such lesions in 72 % (sensitivity). Positive or negative predictive values of 100 % or 92 % were achieved. Since a sensitivity of 100 % cannot be reached at the moment, MR arthrography cannot replace arthroscopy. However, it could be a potent additional tool for wrist diagnosis if intraarticular contrast is used. It can facilitate the diagnostics and the indication for surgery of the wrist and help to reduce arthroscopic interventions for purely diagnostic purposes and without any therapeutic consequences. With improvement of the technique of magnet resonance tomography we can expect a further increase of accuracy in the clinical use of the MR arthrography in the diagnostic workup of the wrist.