With the increasing number of implantation of total ankle arthroplasty a higher rate of pitfalls and failures has to be expected.

Intra- and postoperative complications in total ankle arthroplasty, their sources of failure and revision options are demonstrated.

In the time of 7/97 until 1/06 269 S.T.A.R. total ankle prostheses have been implanted at our hospital.

Intraoperative complications occurred in 7 cases (4 fractures of the malleolus medialis, 2 fractures of distal fibula, 1 fissure of talus).

We observed early complications in form of delayed wound healing (n=31) and 4 deep infections. A higher incidence of secondary wound healing is shown in rheumatoid arthritis patients in comparison to patients with OA.

Late complications included persisting intraarticular synovitis, especially in rheumatoid arthritis, an impingement (11 cases) and osteolysis (4 cases).

Revision surgery was performed in 45 cases (16.7%) 1.5 years after primary implantation (14 operations with problems in secondary wound healing, 9 lengthenings of the Achilles tendon with a dorsal capsulotomy (2 rheumatoid arthritis patients), 11 revisions of the PE gliding core with resection of periarticular hypertrophic bone formation, 4 revisions of singular components, 2 complete revisions of the prosthesis, 4 ankle fusions, 1 amputation. Only in 18 cases (6.7%) these complications and the following surgical procedures influenced the satisfaction of the patients.

Despite the demonstrated complications, total ankle arthroplasty is more than an alternative to open ankle arthrodesis in the progressive phases of arthritic joint destruction, also in RA at a LDE stage ≥ III.

Background: In 80% of patients with rheumatoid arthritis the metacarpophalangeal (MP) joints are involved with increasing destruction and loss of function. Silicone arhtroplasties of the MP joints produce a limited range of motion, increasing osteolysis and fractures of the implants. The cementless, unconstrained design of the ElogenicsTM prosthesis is a new concept for treating the MP joints of rheumatoid patients.

Methods: In a prospective study 72 ElogenicsTM prosthesis were implanted, 62 in patients with rheumatoid arthritis, osteoarthritis (n=4), polyarthritis (n=5) and 1 after revision of a silicone implant. The patients were reexamined after an average follow up of 21 months (12–51 months) clinically and radiologically.

Results: The average active range of motion for extension to flexion increased from 0/18/65° before surgery to 0/14/71° after surgery. The remaining ulnar drift was 12° (preoperative 18°!). Pain in the visual analogue scale improved from 2.3 to 1.7 postoperatively. Eight palmar luxations of the implants were recognized. They were revised and are stable during the follow-up. No infection occurred. Two prostheses were changed because of loosening. The X-rays showed osteointegration in the metacarpal components. Radiolucent zones were found in progress at the basis on the palangeal components.

Conclusion: The short- and midterm results after implantation of the cementless, unconstrained ElogenicsTM prosthesis show an improved hand function and pain relief. The design of the implant may solve the accepted postoperative problem of instability of the MP joints.

In 85 % of the patients with rheumatoid arthritis the MCP-joints are involved with incressing deterioration an loss of function. The standard replacement of the MCP-joints using the Swanson-Silastic Spacers shows pain reduction and a realigment of the fingers, but the functional capacity is not improved.

The HM-MCP-arthroplasty offers a concept for better function an restoration of the rheumatoid hands and osteoarthritis.

In a prospective multicenter study 63 HM-MCP arthroplasties have been implanted. We used the redesigned model (PE-metacarpal head and Ti-ODH phalangeal base) with titanium stems. The follow up-time is 18 months (6 – 40 months). All patients are controlled with clinical and radiographic evaluation.

The active ROM of the MCP-joints demonstrated on average flex./ext. 65/10/0 (preop. 70/15/0). The grip strength at FU demonstrated 80 % of the untreated contralateral control hand. Pain has been improved using the verbal pain scale at 1.6 (preop. 2.1).

Radiographically all metacarpal and phalangeal stems show an osteointegration of the implants. Radio-lucent lines of < 1 mm have been detected at the phalangeal base without a sign of loosing.

Complications: 1 palmar luxation with a successful closed reposition, 1 ulnar subluxation of the fifth finger, 1 unsuccessful revised palmar luxation.

The results of the uncemented, unconstrained HM-MCP-arthroplasty show an improvement of the hand function and pain reduction. This endoprosthesis gives a new chance to treat the rheumatoid hand at an earlier stage of destruction before severe contracture of the soft tissues.

Introduction and aim: In a prospective comparative study we were interested in the question, wether the total ankle arthroplasty in the midterm FU, especially in patients with RA, is a successful and correctly indicated surgical procedure. We compared our clinical and radiological results with a cohort of patients with OA. Furthermore we analysed especially the rheuma patients for their known periarticular osteopenia and the cementless fixation as a possible contraindication for the ankle arthroplasty.

Material and methods: With a mean FU of 4,4 years and a total number of 153 total ankle arthroplasties from 07/1997 to 12/2003 we assessed 92 patients with 94 S.T.A.R total ankle arthroplasties. Indication for this surgical procedure was the rheumatoid arthritis in 26 patients (27.7%) and an idiopathic osteoarthritis of the upper ankle joint in 29 cases (30.8%), furthermore a posttraumatic osteoarthritis in 39 patients (41.5%)

Results: The functional increase in their range of motion (ROM) and the significant decrease of pain are the most important and impressing facts for the patients.

The increase of ROM in all patients is 17.9 (RA: 18.7 /OA: 16.6). Significant pain relief is described by 92.4% of patients, here all the groups showed no significant differences. An increase in the clinical outcome measured by the Kofoeds Ankle Score is seen from < 70 pts. preoperatively (100% of patients) to > 75 pts. postoperatively (82.3% of patients). The most frequent complication especially in patients with RA is a delayed wound healing (19%), but the revision rate is higher in patients with traumatic and idiopathic osteoarthritis (17% OA /13% RA). A secondary arthrodesis has to be performed only in 2 OA cases.

Conclusion: Rheumatoid arthritis in the LDE stage IV and V is the adequate indication for the S.T.A.R. prosthesis. The functional benefit and the clinical outcome is satisfying, the results for the rheumatoid arthritis patients are comparable to other indications. Periarticular osteopenia is not considered as a contraindication.

Introduction:

In 1994 Kofoed and Stürup already confirmed that within a follow-up of 10 years total ankle arthroplasty demonstrated a significant clinical improvement for the patients.

In recent studies a 12 – year survival rate even of 84% was described (Kofoed, 1995).

Methods:

In a retrospective study we evaluated the short – and midterm results in 44 patients with unconstrained total ankle arthroplasty and cementless fixation. These ankle replacements were performed between 8/1997 and 12/2000. A critical assessment concerning the indications and contraindications of this arthroplasty was performed due to the fact, that this surgical technique is not yet mentioned as a routinely performed surgical procedure of the ankle. The advantages in comparison to the open or arthroscopically assisted arthrodesis of the ankle were described.

As initial diagnosis rheumatoid arthritis (n:16), post-traumatic osteoarthritis (n:10) or idiopathic osteoarthritis of the ankle (n:18) was mentioned. The patients age varied from 24 to 78 years; the 24 years old patient suffered from a posttraumatic osteoarthritis, in the 78 years old patient contralateral total ankle arthroplasty was performed 13 years ago.

Results:

There was a delay in superficial wound healing in 11 cases, in 4 cases soft tissue revision and once plastic surgery had to be performed. One female patient with RA had a postoperative deep infection after preoperative radiosynoviorthesis of the ankle.

Additionally osteosynthetical reconstruction of the fibula (n:2) and the talus (n:1) was necessary. One patient underwent revisional surgery due to progressive wear and fracture of the polyethylene inlay. Furthermore three patients suffered from continuing instability, that one had a secondary open arthrodesis and two a syndesmoplasty combined with revision of the PE inlay.

The radiological examination offered migration and progredient radiolucency lines especially near to the tibial part of the prosthesis in three cases.

Nevertheless more than 80% of the patients were satisfied or very satisfied with their ankle arthroplasty, only 4 patients now would have denied the surgical procedure. As main improvements reduction of pain and increased mobility (ROM: > 40°) were mentioned.

Conclusions:

The success of total ankle arthroplasty may depend on exact technique, correct hindfoot alignment and sufficient capsuloligamentous stability of the ankle. So this surgical procedure may provide a high rate of functional improvement for the patients and may prevent the probably necessary arthrodesis.

Introduction:

The periprosthetic loss of bone mass may compromise the longevity of femoral stems in THA. The benefit of metaphyseal hydroxyapatite - coating remains controversial. Better Osseo integration is reported by Jaffe and Scott, whereas Dorr considered no clinical or radiographic value for the use of hydroxyapatite.

Methods and materials:

Evaluating the influence of this hydroxyapatite - coating of the femoral stems a double blind, randomized prospective study with two groups of uncemented total hip replacements using the Endoplus-SL-Plus-stem was conducted. Matched pairs with and without hydroxy-apatite-coating were compared clinically, radiographically and by QDR-bone-densitometry for 5 years with an average follow-up of 3, 7 years. 92 new hydroxylapatite-coated titanium stems and 90 non-coated stems were implanted. Main indications were an osteoarthritic (primary osteoarthritis / hip dysplasia / femur head necrosis: n = 134 (73, 6%) destruction or a postinflammatory arthritic destruction due to a rheumatoid arthritis (n = 48 ( 26, 4%))

Results: Concerning the clinical outcome the Harris hip score presented no significant differences between the two groups The range of motion and the need of drugs did not differ. All patients demonstrated good to excellent clinical results. No serious complications or adverse events in this study except in one case were described. This patient had to undergo one revision surgery due to a primarily to small implanted femoral stem with recurrent luxations of the hip.

As expected but as a very exciting fact the preoperatively performed osteodensitometric analysis in rheumatoid arthritis patients offered a significant loss of bone mass ( − 25, 1 % !) in comparison to the osteoarthritic group. (RA: 994 g/ cm ² ↔: 1328 g / cm2)

The HA-coated stems showed a statistical significant increase in bone mineral density in Gruen zone 1 (789 g/cm² vs. 711 g/cm²), zone 6 (1251 g/cm² vs. 1066 g/cm²) and in zone 7 (1021 g/cm² vs. 908 g/cm²). There were no significant differences in zones that were not HA-coated. The frequency of proximal radiolucencies was clearly reduced in the HA-coated group (Gruen zone 1: 12, 9 % vs. 26, 7 %, zone 7: 19, 2 % vs. 30, 1 %, zone 8: 3, 7 % vs. 14, 8 % and zone 14: 9, 9 % vs. 16, 1 %).

Conclusion:

The titanium/hydroxyapatite-coating enables a better early osteointegration of the metaphyseal area also in RA patients of the non-cemented Endoplus-SL-Plus-stem with an increase in bone mineral density and less proximal radiolucencies. Longterm results will reflect, whether there is a correlation with a better outcome and clinical advantages.

Problem:

The torsion of the humerus is defined as the angle between the axis of the humeral head and the axis of the trochlea humeri relative to the long axis of the humerus. In performimg shoulder arthroplasty it is an essential part of the procedure to restore the individual torsion. In some cases it might be difficult to detect the orignal border of the joint surface and thus the torsion. This situation occurs in severely destructed humeral heads as well as in fracture cases.

In the literature an average retrotorsion is given between 20–30 degrees, with a high standard deviation.

The aim of the following study was a critical analysis, if the sulcus intertubercularis can serve as an anatomical landmark for the orientation of humeral torsion in shoulder arthroplasty.

Method:

First, we defined the indivdual humeral torsion ( n = 40 ) by two independent anthropometric methods ( method according to Martin, method according to Knußmann).

Afterwards, the results of the measurements were compared to CT- scans taken by the same bones. The CT- measurements were performed by the method of Dähnert and Bernd, who used the midpoint of the humeral joint surface and the sulcus intertubercularis defining the proximal axis of retrotorsion.

Statitstical analysis was performed with varianz analysis, U-test according to Wilcoxon and Smirnov –Komolgorow test.

Results:

The anthropometric measurements according to Martin revealed an average retrotorsion of 23° degrees (+/− 9, 15 °). Comparing these data with the second anthropometric method ( according to Knuβmann) the measurements demonstrated a highly significant relationship( p < 0, 005).

The CT- measurements according to Dähnert showed an average of 53, 8° degrees ( +/− 8, 91°).

The different results were easy to explain because both methods used different bony landmarks.

Performing a varianz analysis the data showed a significant relationship ( p < 0, 05 ).

The average difference between the anthropometric – and the CT-measurements was 31 ° +/− 5, 93 ° degrees ( Minimum 14 °, Maximum 50°)

Conclusion:

In severely destroyed shoulder joints it is sometimes difficult to identify the original anatomic borders of the joint surface. The reconstruction of the anatomical neck is the precondition to detect the individual retrotorsion performing a shoulder arthroplasty.

There are two options if that fails.

You may use an average retrotorsion of about 23 degrees or you may use the sulcus intertubercularis as an anatomical landmark. It only makes sense to use the Sulcus as an anatomical landmark, if there is a constant relationship between the orientation of the sulcus and the retrotorsion of the proximal humerus.

With our measurements we could demonstrate a close relationship between the sulcus and the orientation of the humeral joint surface, relative to the long axis of the humerus ( p< 0, 005 ).

The average difference between the anthropometric – and the CT-measurements was 31 ° +/− 5, 93 ° degrees ( Minimum 14 °, Maximum 50°). Using a standard head of 48 mm and adding the distance to the greater tubercle one should go about 10 mm lateral to the center of the sulcus intertubercularis. The distance varies with the head size.

The probability to match the individual torsion is higher using the sulcus intertubercularis as an anatomical landmark compared to the average retrotorsion.