[Endoprosthetic surgery of the elbow]. / Endoprothetik des Ellenbogens.

Artificial joint replacement has found a firm place in orthopaedic surgery since its first introduction in the late 1960s. While the initial fixed bearing implants tended to progress to early loosening, the development of so-called "sloppy joints" has seen a major advance in the survival and success rate of this arthroplasty. The surgical approach and technique have also been modified in such a way as to allow a complete ventral release of a flexion contracture, while at the same time preserving the integrity of the extensor mechanism. In this way, the improvement of the biomechanics of the implant combined with diligent surgical technique have enhanced this procedure dramatically. Between 1978 and 1999, 305 GSB 3-type prosthesis were implanted, with the underlying pathologies being rheumatoid arthritis (77%), posttraumatic arthritis (21%) and degenerative arthritis (2%). The range of motion could be significantly improved from the pre-operative state for extension as well as flexion. This was even more obvious in the rheumatoid than in the posttraumatic situation. The survival rate for this type of implant was 90% at 10 years, with the implants after rheumatoid surgery faring somewhat better than those of the posttraumatics. Alternative treatment options, such as resection arthroplasty, distraction arthroplasty, or arthrodesis, are nowadays employed only in rare cases where a previous infection, personal preference or an inability by the patient to co-operate in a rehabilitation program have to be considered. The overall functional results of these types of treatments seem to be inferior to that of elbow arthroplasty. Therefore, this procedure is recommended not only for advanced degenerative and rheumatoid pathologies, but also in cases of posttraumatic arthrosis.

Present state-of-the-art in elbow arthroplasty.

Prosthetic joint replacement of the elbow is, with some delay in comparison with the shoulder, the finger joints and especially the hip and knee joint, becoming a routine operation at least in more specialised orthopedic and trauma centers. In the seventies and eighties, more than 80% of the indications were in patients affected by rheumatoid arthritis, in which both sides were typically affected, seriously jeopardising their independence in activities of daily living. In the last decade an increasing number of posttraumatic osteoarthritic cases were included in the indications. Among the numerous prosthetic devices, only a few have stood the test of time (> 10 years); a meta-analysis of the world literature shows an average follow-up of less than 5 years. Two main types of prostheses must be distinguished, linked and non-linked. The linked prostheses are, with few exceptions, so-called sloppy hinges with a clearance between both components, permitting movement in the sagittal plane and in the frontal plane and also some rotation. Using the normal anatomical stabilising structures, the stresses on the interface are reduced. This type of linked prostheses has a wider range of possible indications than the non-linked resurfacing prostheses, which require a largely preserved bone stock and intact ligaments in order to avoid instability with subluxations or even dislocations. Resurfacing prostheses can be more or less constrained according to the degree to which they mimic normal elbow anatomy. In order to reduce the stresses on the interface, the more constrained resurfacing prostheses make additional use of an intramedullary stem. The fixation of the device in the bone is achieved with bone cement in nearly all the linked and non-linked prostheses. Sloppy hinges with condylar configurations (as the GSB III elbow prosthesis) or an anterior flange (Coonrad-Morrey) further reduce the stresses on the interface and have better long-term results. Special instruments help to place the prosthesis in correspondence to the normal center of rotation and to minimise the bone resection needed and the risk of intra-operative complications (condyle fractures, shaft perforation). The results concerning pain relief and mobility are, for all properly placed prostheses, very satisfactory in the first years. A reliable account of long-term results (> 10 years of non-interrupted series of elbow prostheses) has so far been given only by a few authors. In cases with rheumatoid arthritis the survival rate at 10 years reaches 90%; the complication rate however is still definitely larger than with hip, knee and shoulder prostheses. This is particularly true for posttraumatic OA cases. Aseptic loosening, infection, instability and ulnar nerve lesions are at the fore and about twice as frequent as in RA, especially in patients below 60 years of age. In order to keep a safe retreat possibility open, we insist on the best possible preservation or reconstruction of normal anatomy (e.g. condyle reconstruction) when implanting an elbow prosthesis.

Alpine and cross-country skiing after total hip replacement: 2 cohorts of 50 patients each, one active, the other inactive in skiing, followed for 5-10 years.

2 groups of 50 patients each, matched for age, weight, height, gender and type of implant, were clinically and radiographically examined after THR. Group A regularly carried out alpine skiing and/or cross-country skiing, while group B did no winter sports. At 5 years, no signs of loosening were found in group A, whereas 5/60 implants in group B had signs of loosening, mostly of the femoral component (p < 0.05). At 10 years, 30 patients remained in group A and 27 in group B. No new cases of loosening were found in group B, but 2/30 cases in group A. There was a higher (p < 0.05) average wear rate in group A (2.1 mm) than in group B (1.5 mm). The wear rate was particularly high (3-4 mm) in physically very active patients in group A with localized osteolysis at the interface. It seems likely that in an even longer follow-up, the number of cases of aseptic loosening would be greater in group A than group B. Our findings, combined with the results of previously-published biomechanical studies, do not provide any evidence that controlled alpine and/ or cross-country skiing has a negative effect on the acetabular or femoral component of hip replacements. The results of the biomechanical studies indicate, however, that it is advantageous to avoid short-radius turns on steep slopes or moguls.

Long-term results of the GSB III elbow arthroplasty.

Between 1978 and 1986, 59 patients received a GSB III elbow prosthesis, six of them in both elbows. Rheumatoid arthritis (RA) was the underlying cause in 51 of the patients and post-traumatic osteoarthritis (PTOA) in eight. Of these, 24 patients (28 prostheses) have since died; two, both operated on bilaterally, had had their implants for more than ten years and had already been assessed for inclusion in the long-term follow-up. Two patients, each with one elbow prosthesis, have been lost to follow-up and three males who are still living (two with PTOA, one with juvenile RA) had their prosthesis removed before ten years had elapsed. The remaining 32 patients (28 RA, 4 PTOA) with 36 GSB III elbows were examined clinically and radiologically after a mean period of 13.5 years. Pain was considerably reduced in 91.6%. Mobility was increased by 37 degrees in those with RA and by 67 degrees in those with PTOA. There were three cases of aseptic loosening and three of deep infection. The main complication was disassembly of the prosthetic component in nine elbows (13.8%). This last group included two patients with postoperative fractures unrelated to the operative technique and one with neuropathic arthritis. Ulnar neuritis occurred in two patients. Since 87.7% of all the GSB III prostheses implanted in this period remained in situ, our results are comparable with those for hip and knee arthroplasty.

[Shoulder joint instability after primary arthroplasty]. / Schulterinstabilität nach primärem Schultergelenkersatz.

Instability is one of the most common complications after shoulder arthroplasty. The literature cites subluxation or luxation to occur between 0% and 38% in various studies. Instabilities may present either as subluxation or frank dislocation, and may be directed in an anterior, posterior, inferior or, depending on the state of the rotator cuff, cranial direction. The stability of any shoulder joint is given by the balance of the muscles directing the forces around the shoulder joint in association with the passive stabilizers of the shoulder joint capsule as well as the bony contours between glenoid and humeral head. Any disturbance of this delicate balance will lead the shoulder into instability, particular so if bony erosion patterns such as posterior glenoid wear in osteoarthritics will develop subluxation early on. Therefore implantation of any prosthesis is required to be done in the appropriate version as to avoid secondary instability through the prosthetic components. In the study undertaken here instability was found to be the most common complication in 44 shoulder revision surgeries. The result with an average Score of 41.9 recorded after Constant demonstrates that the excellent and good results obtained with primary arthroplasties can not be expected in revision surgery. Posterior instability may be present just as well as the more easily observed anterior instability. Separate to frank luxation or instability is the late cranialisation of the rotator cuff deficient shoulder which, although resulting in many cases in superior anterior subluxation, will mostly be seen as a late complication after arthroplasty.

[The rheumatic hand]. / Die rheumatische Hand.

The hand (wrist and fingers) is one of the regions most frequently affected by rheumatic arthritis (RA). The nature of the alterations involved means it is possible to interpret the clinical picture as RA even from the external appearance. Obviously the functional handicap affects activities of daily living, and the insult to the patient's aesthetic sensibilities imposes an additional, psychological, burden. A generally satisfactory limitation of damage can only be expected from professionals who work well together as a team. The ability to devise a therapy plan with the right priorities is the mark of those who have mastered the art of surgery for rheumatic conditions. Operative treatment presupposes failure of a conservative therapy carried out according to modern views. In addition to operations on the affected joints, operations on the tendons of the hand are also highly significant in terms of function. The interventions that can be performed on the joints embrace synovectomies, arthroplasties and arthrodeses. In the last 20 years the absolute number of joint synovectomies has fallen, since at least in treatment of the early stages radiosynoviorthesis has become increasingly important, especially for the metacarpophalangeal (MP) and proximal interphalangeal (PIP) joints. Operative synovectomy is now considered when radiosynoviorthesis fails or in more advanced stages (Larsen 3) and when reconstruction procedures (especially on the tendons) are necessary. The chances are also better with open synovectomy (with or without resection of the head of the ulna) at the wrist. The results of synovectomy are not so impressive from the radiological aspect as from the clinical viewpoint, since as a result of the removal or attenuation of pain the function is often improved to the status of more than 10 years before and valuable time is thus gained. When the destruction is too far advanced arthroplasty is considered, especially for the MP joints but increasingly also for the PIP joints. Arthrodesis is a still highly valuable procedure for the wrist, since there is no really satisfactory artificial joint. An arthroplasty can only be successful if the tendons are intact. Tenosynovectomy and repair of ruptures have a good prognosis if appropriate techniques are used. The correction of such typical deformities of the fingers as buttonhole and swan neck deformity requires some of the technically more demanding operations.

Shoulder instability after primary shoulder joint replacement.

Instability is one of the most common complications after shoulder arthroplasty. The literature cites subluxation or luxation to occure between 0 % and 38 % in various studies. Instabilities may present either as subluxation or frank dislocation, and may be directed in an anterior, posterior, inferior or, depending on the state of the rotator cuff, cranial direction. The stability of any shoulder joint is given by the balance of the muscles directing the forces around the shoulder joint in association with the passive stabilizers of the shoulder joint capsule as well as the bony contours between glenoid and humeral head. Any disturbance of this delicate balance will lead the shoulder into instability, particular so if bony errosion patterns such as posterior glenoid wear in osteoarthritics will develop subluxation early on. Therefore implantation of any prosthesis is required to be done in the appropriate version as to avoid secondary instability through the prosthetic components. In the study undertaken here instability was found to be the most common complication in 44 shoulder revision surgeries. The result with an avarage Score of 41.9 recorded after Constant demonstrates that the excellent and good results obtained with primary arthroplasties can not be expected in revision surgery. Posterior instability may be present just as well as the more easily observed anterior instability. Separate to frank luxation or instability is the late cranialisation of the rotator cuff deficient shoulder which, although resulting in many cases in a superior anterior subluxation, will mostly be seen as a late complication after arthroplasty.

The rheumatic hand.

The hand (wrist and fingers) is one of the regions most frequently affected by rheumatic arthritis (RA). The nature of the alterations involved means it is possible to interpret the clinical picture as RA even from the external appearance. Obviously the functional handicap affects activities of daily living, and the insult to the patient's aesthetic sensibilities imposes an additional, psychological, burden. A generally satisfactory limitation of damage can only be expected from professionals who work well together as a team. The ability to devise a therapy plan with the right priorities is the mark of those who have mastered the art of surgery for rheumatic conditions. Operative treatment presupposes failure of a conservative therapy carried out according to modern views. In addition to operations on the affected joints, operations on the tendons of the hand are also highly significant in terms of function. The interventions that can be performed on the joints embrace synovectomies, arthroplasties and arthrodeses. In the last 20 years the absolute number of joint synovectomies has fallen, since at least in treatment of the early stages radiosynoviorthesis has become increasingly important, especially for the metacarpophalangeal (MP) and proximal interphalangeal (PIP) joints. Operative synovectomy is now considered when radiosynoviorthesis fails or in more advanced stages (Larsen 3) and when reconstruction procedures (especially on the tendons) are necessary. The chances are also better with open synovectomy (with or without resection of the head of the ulna) at the wrist. The results of synovectomy are not so impressive from the radiological aspect as from the clinical viewpoint, since as a result of the removal or attenuation of pain the function is often improved to the status of more than 10 years before and valuable time is thus gained. When the destruction is too far advanced arthroplasty is considered, especially for the MP joints but increasingly also for the PIP joints. Arthrodesis is a still highly valuable procedure for the wrist, since there is no really satisfactory artificial joint. An arthroplasty can only be successful if the tendons are intact. Tenosynovectomy and repair of ruptures have a good prognosis if appropriate techniques are used. The correction of such typical deformities of the fingers as buttonhole and swan neck deformity requires some of the technically more demanding operations.

Compression arthrodesis of the rheumatoid ankle and hindfoot.

The reported frequency of involvement of the rheumatoid ankle and hindfoot varies between 9% and 70%. Fusion of the ankle joint, the subtalar, talonavicular, or calcaneocuboidal joint (Chopart's joint) or all of them is the preferred method of treatment for severe rheumatoid involvement causing pain, instability, and/or severe deformity. Ankle arthroplasty is indicated rarely. Pantalar arthrodesis is performed more frequently than talonavicular fusion or ankle fusion. Reported rates of fusion after compression arthrodesis of the ankle joint vary from 65% to 90%, averaging 80% to 85%. Higher success rates of as high as 95% were obtained with internal lag screw fixation as proposed by Wagner. The result of various combinations of arthrodesis (n = 54) of the ankle joint, the subtalar joint, and Chopart's joint in 43 patients with rheumatoid arthritis operated on in a 10-year period from 1984 through 1993 are presented. In all cases internal fixation by lag screws according to Wagner was used with a modified lateral approach incorporating osteotomy of the distal fibula. The technique is described in detail. Solid fusion was obtained in 21% of the cases after 8 weeks, in 9% of the cases after 12 weeks, and in 92% of the cases after 16 weeks. In 8% (3 patients) revision because of delayed union or nonunion eventually led to bony fusion. Postoperative pain, walking capacity, gait, and the subjective outcome were assessed. Complications occurred in 16%, revision was performed in 11.6% of the cases; in all cases healing was obtained. Overall patient satisfaction was 93%.

Quantitative gait analysis after bilateral total knee arthroplasty with two different systems within each subject.

The functional behavior of two kinematically different knee arthroplasty systems within each subject was studied by gait analysis (three-dimensional kinematics, kinetics, dynamic electromyography) in five elderly patients, 2 to 5 years after bilateral surgery. Clinical results were good, yet gait velocity was reduced (range, 0.57-1.1 m/s), with a shortened stride length and a decreased duration of single-limb stance in all subjects. Force plate recordings revealed an undynamic gait with slow loading, reduced modulation of the vertical forces, and poor fore/aft shears. Sagittal plane knee motion during gait was reduced in all subjects, with trunk and pelvic compensation patterns for foot clearance. Muscle activity around the knee was prolonged bilaterally, with activity modulation related to the motion pattern. Although the stride parameters were quite symmetric, there was a marked asymmetry of the motion pattern, with a side-to-side difference of peak knee flexion during stance and swing phase of up to 15 degrees. This finding, however, was not clearly related to the type of prosthesis. Even within one subject, significant side-to-side variability may persist, which leads to asymmetry of the motion pattern, unrelated to the kinematic design of the implant. Other factors, such as the patella-extensor mechanism, ligament balancing, leg-length discrepancy, proprioception, continuation of a preoperative habit, or a contralateral influence, may explain part of the asymmetry seen in these subjects.

Infection of a total knee joint prosthesis by peptostreptococcus micros and propionibacterium acnes in an elderly RA patient: implant salvage with longterm antibiotics and needle aspiration/irrigation.

We describe the favourable long-term outcome after late total knee joint prosthesis infection in an elderly RA patient. Peptostreptococcus micros and Propionibacterium acnes were cultured from the synovial fluid, and the finding of a coexistent abscess at the root of a wisdom tooth suggested a dental origin to the joint infection. Long-term antibiotics in conjunction with aspiration/irrigation resulted in salvage of the implant and an excellent functional outcome.

Late complications in elbow arthroplasty.

The world literature (1986 to 92) reports an amazingly high complication rate of elbow arthroplasty, amounting to 43%. Accordingly, we also find a high revision rate (18% on average) and a considerable rate (15%) of permanent complications. These figures do not correspond to our own experience with the GSB III (Gschwend/Scheier/Bähler) elbow prosthesis, a sloppy hinge with flanges on the lower and anterior part of the distal humerus. Our respective figures of complications are two to four times lower for rheumatoid elbows. When complications are discussed, a clear distinction of the type of prosthesis is mandatory, because linked or nonlinked and nonconstrained or semiconstrained prostheses have specific complications. The following complications are discussed separately: loosening (radiologic and clinical), ulnar neuropathy, infection, dislocation and subluxation, uncoupling, intraoperative bone fractures, and failure of the implant. The possible causes are analyzed, and means to avoid or treat these complications are discussed. We conclude that even in the long term ( > 10 years), results obtained with elbow arthroplasty are approaching those of hip and knee arthroplasty.

[Infection following shoulder and elbow arthroplasty. Diagnosis and therapy]. / Infekt nach Schulter- und Ellbogenarthroplastik. Diagnostik und Therapie.

The rate of infection reported in recent publications is 0.8% after shoulder arthroplasty and ten times higher (8.1%) after elbow arthroplasty. The figures for shoulder arthroplasty correspond well with our own rate of revision for infection of 0.5% after 363 primary shoulder replacements. However, our average rate of revision for infection (1.8%) after 278 GSB-III elbow arthroplasties was considerably lower and included rheumatoid as well as post-traumatic indications. Our experience concerning etiologic factors, nature, diagnosis, treatment options, and long-term consequences of superficial and deep infections after shoulder and elbow arthroplasty are discussed for each joint separately and in relation to the literature.

[Multiple joint replacement in chronic rheumatoid arthritis: results, indications]. / Multipler Gelenkersatz bei chronischer Polyarthritis: Ergebnisse, Indikationen.

Rheumatoid arthritis, steadily progressive and affecting many joints, is a real challenge for the orthopaedic surgeon. Thorough assessment and long-term planning to maximize overall performance requires clear orthopaedic thinking based on wide experience. The final aim is to enable the patients to walk and be independent. Over the last 30 years, the surgery of the rheumatic diseases has become a well-established specialty within orthopaedic surgery. Open synovectomy still has a place. In badly damaged joints, however, only prosthetic joint replacement has a fair chance. Total hip replacement is now a common procedure. Yet many problems regarding long-term performance remain unclear. This is even more pertinent for total knee replacement. Operations on the upper limbs must enable the patient to become less dependent of other people's help. Artificial shoulder joints have become more popular, and elbow joint replacement has been a particularly important field at the Wilhelm Schulthess Clinic. Multiple joint replacement is often necessary and can improve the quality of life for these badly stricken patients.