[Differences in hip prosthesis implantation in a non-urban region]. / Unterschiede in der Hüftendoprothetik in einer Nicht-Grossstadt-Region.

AIM: The aim of the study was to analyse differences of early results after total hip replacement performed at various hospitals. METHOD: A total of 37 consecutive patients submitted for postoperative rehabilitation were examined. These patients were referred from 18 different hospitals. In an assessment sheet, personal data, age, indication, operating department (surgical or orthopedic), side, length of skin incision and early X-ray presentation with regard to cup angle, position of greater trochanter in relation to head of prosthesis, varus/valgus angle of femoral prosthesis, and cementation were recorded. RESULTS: Of the 37 patients, 26 were female, 11 male. Average age was 62.9 +/- 10.4 years. Degenerative osteoarthritis was present in 23 cases, fractures in 6 cases, there were 6 patients with osteoarthritis following hip dysplasia, 1 pathological fracture, and 1 aseptic necrosis of the femoral head. The skin incision length varied from 8 to 31 cm, averaging to 16.8 +/- 5.3 cm. Implantations were cementless in 20 cases, cemented in 12, and partly cemented in 5 cases. Using a THR-Early-Result-Score of 25 points maximum, # 7 implantations were scored as normal, 16 subnormal, 10 atypical, and 4 highly atypical. CONCLUSION: The data presented show an incidence of 81% non-ideal implantations which is considered surprisingly high. Potential reasons are discussed. It is suggested that efforts to improve the quality of total hip replacements should be made.

[Experimental stability of a new implant-free fixation technique in ACL replacement]. / Primärstabilität einer implantatfreien Verankerung des Lig.-patellae-Transplantats beim vorderen Kreuzbandersatz.

The purpose of the study is to establish data on the stability of an ACL replacement. In 40 human cadaver knees, either a mid patellar ligament third with a trapezoid bone block on one side was fixed on the femoral side in a 2-diameter drill hole, or a conventional interference screw fixation was applied. Average primary stability amounted to 570 N (+/- 100 N) for the bone-blocking technique, and to 402 N ( +/- 79 N) for the interference screw fixation. When statistically tested by variance analysis, stability was significantly higher for the bone blocking technique than with interference screw fixation (p < 0.05). Thus, when using a mid-patellar ligament third for ACL reconstruction, the new implant-free technique described here appears to be a practical and reliable method for femoral graft fixation.

[Changes in psychophysiologic status during inpatient rehabilitation in the orthopedics service--a preliminary study]. / Psychophysiologische Befindensveränderungen während einer stationären Rehabilitation im Bereich Orthopädie--eine Erkundungsstudie.

OBJECTIVES: Assessment of non-operative treatment of orthopaedic diseases is sometimes considered difficult. The purpose of this retrospective longitudinal study on the one hand is to evaluate the formal quality of questionnaire data under routine conditions in an in-patient rehabilitation hospital and on the other hand to study the impact of additional psychologic treatment on the outcome of patients who received conservative treatment for chronic orthopaedic diseases. PATIENTS AND METHODS: During a 7-month period, a total of 900 patients received a standardized questionnaire at the beginning and the end of a 4-week inhouse treatment for chronic orthopaedic diseases. A questionnaire handed out to the patients at arrival includes 33 items of psychophysiologic interest. At discharge, a modified questionnaire was used, focussing on the course of complaints during the treatment period, and including additional control-questions for consistency. Return of the questionnaires was voluntary, no pressure was applied, no effort was made to correct inconsistent or missing data. The results presented here are based on 105 orthopaedic patients who returned both questionnaires complete with consistent data. Of these, 44 received additional psychologic treatment by a psychologist, while 61 did not. Participation or non-participation in the psychologic treatment was the grouping variable in this study. RESULTS: For only 189/900 (21%) of the patients taking part in the study complete and consistent questionnaires were available for analysis. For the 105 orthopaedic patients, no significant score differences at arrival between the groups were detected (p = 0.38) using the Mann-Whitney U-test. At discharge, the mean rank sums for the psychological intervention group was 45.7, while it amounted to 58.3 in the control group, indicating significantly stronger improvement of symptoms in the intervention group (p = 0.04). CONCLUSIONS: Under routine conditions without any arrangements to ensure data quality a great amount of incomplete and/or inconsistent data has to be expected. For subsequent studies, this fact has to be taken into account. Irrespective of this aspect, complementary psychologic treatment of certain orthopaedic diseases seems to lead to significantly better results of treatment, as assessed by a psychophysiological questionnaire.

Magnetic resonance imaging and knee stability following ACL reconstruction.

This study was undertaken to determine whether there is a correlation between magnetic resonance imaging (MRI) and clinical success after reconstruction of the anterior cruciate ligament (ACL). In a prospective study, 28 patients underwent clinical and MRI examination 3 to 5 years after ACL reconstruction with either the semitendinosus tendon (n = 15) or patellar ligament (n = 13). Knee stability was assessed both clinically and by KT-1000 arthrometer testing. Magnetic resonance imaging was performed with a 0.2-T dedicated system (Artoscan, Esaote, Italy) including sagittal and oblique coronal T1 and T2-weighted images. Magnetic resonance images were evaluated by two readers with regard to signal intensity and continuity of the ACL reconstruction and presence or absence of posterior cruciate ligament buckling. Knee stability and MRI evaluation were each summarized in a 6-point score. Statistical correlation was checked with the Spearman ranked correlation for testing non-normal distributed samples. Statistical testing of all patients' results together showed a significant correlation with a prediction value of 12%, indicating no significant correlation between clinical results and MRI evaluation. Separate statistical testing of the patellar ligament and semitendinosus patients' results showed no significant correlation in either group at all. Thus, no correlation between clinical stability and MRI could be established. Magnetic resonance images after ACL reconstruction using the techniques mentioned above should be interpreted with caution, as they may not relate to the clinical function of the ligament.

[Reconstruction of acute anterior cruciate ligament rupture by suture and semitendinosus tendon augmentation.]. / Die Rekonstruktion frischer vorderer Kreuzbandrupturen durch Naht und Semitendinosusaugmentation.

GOAL OF SURGERY: Restoration of normal knee function. INDICATIONS: Acute avulsion of the anterior cruciate ligament (ACL) from its femoral origin. CONTRAINDICATIONS: Mid substance and remote tears. POSITIONING AND ANAESTHESIA: Supine. Knee flexed, hip bent to 30 degrees . General or regional anaesthesia. SURGICAL TECHNIQUE: Step 1: Arthroscopy to confirm site of rupture, meniscus repair if necessary. Step 2: Mobilisation of semitendinosus tendon, left attached distally. Step 3: Mini-arthrotomy, securing of ACL stump with atraumatic suture. Step 4: Transfer of ST-tendon through 5 mm drill holes through tibial head and lateral femoral condyle. Step 5: Fixation of tendon and ACL-sutures with staple at the exit of the femoral drill hole. POSTOPERATIVE MANAGEMENT: Knee orthosis for 6 weeks, CPM, physiotherapy. ROM day 0-2: 0-10-10 degrees ; day 3-11: 0-0-60 degrees , day 12-42: 0-0-90 degrees . Increase of weight bearing 10 kg/week from operation date. Bicycling and running permitted 3 months post-op. Full sport activity after muscle power has reached that of opposite side. LMW heparin until full weight bearing. POSSIBLE COMPLICATIONS: Thrombosis. Embolism. Infection. Failure of reconstruction. Osteoarthritis. RESULTS: During 1 year, 116 patients were operated. Follow-up after 42 to 57 months (average 52 months) included 95 patients (82%). Of these, 76 underwent full examination (average age 33 1/2 years, 20-49 years), 11 answered a questionnaire, 8 had suffered re-injury. Average Lysholm score was 92 points (+/-13). Tegner activity scale amounted to 7.2 points pre-injury, 7.1 points at follow-up. Anterior translation (KT 1000 arthrometer testing at 89 N) was identical to opposite side in 25 patients, less than 2 mm in 14, up to 4 mm in 19, up to 6 mm in 15, more that 6 mm in 3 patients. Pivot shift was negative or trace 73 times, and positive in 3 patients. ROM was full in 54 patients, 17 times the flexion was limited up to 10 degrees . Ten times extension lag was less than 5 degrees , and twice between 5 and 10 degrees .

Surgical treatment for myeloma of the bone. A retrospective analysis of 22 cases.

In a retrospective study, 22 patients treated surgically for solitary or multiple myeloma between 1980 and 1993 were analysed. The main complaint was pain. A fracture was observed in 7 cases and motor-sensory impaired neurology due to spinal compression in 3. Apart from incisional biopsies, tumour resections, reductions (with and without stabilization by osteosynthesis) and endoprotheses were performed either at the extremities or on the spine. In addition, radiation and chemotherapy were included in the therapeutical concept. Early mobilization was achieved in all cases, and the 5-year survival rate (Kaplan-Meier method) was 48%. The results presented in this study demonstrate that a variety of surgical interventions can be of importance in the treatment of myeloma of the bone, ranging from biopsy or even curative resections in selected cases to endoprosthetic replacement. Thus, good functional results can be achieved and maintained over often long survival times.

[Unusual late complications following total hip endoprosthesis]. / Ungewöhnliche Spätkomplikation nach Totalendoprothese der Hüfte.

A cementless total hip replacement was implanted in a 52-year-old male patient with coxarthrosis. Rapid cranial migration of the cup and ectopic ossification were subsequently observed. Five years after the original operation, revisional arthroplasty had to be performed to replace the cup. At surgery a large amount of granulomatous tissue and the tip of a deep drainage tube were found. Interposed between the polyethylene inlay and the femoral head of the prosthesis, the drain had not been visible on any of the radiographic controls. The X-ray control performed immediately after the first procedure revealed that the drain had been slung around the neck of the prosthesis stem, a procedure preferred by some surgeons. When the drain was removed, the tip must have been caught between the polyethylene inlay and the femoral head of the prosthesis. It is not clear whether the loosening of the cup was ultimately caused by the increased wear due to the presence of the drain tip. However, in light of this finding we no longer sling the drain around the prosthesis shaft, but lay it along the neck of the femoral component in the same direction as it is routed out transcutaneously.

Bone formation in coralline hydroxyapatite. Effects of pore size studied in rabbits.

We analyzed osseous reactions in the rabbit femoral condyle to coralline hydroxyapatite bone substitutes of various pore sizes by radiology and histology. The results were compared to bone repair of empty cavities and to integration of allografts. Spontaneous bone repair of the empty cavities took approximately 12 weeks, while integration of the cryopreserved allografts occurred after 9 weeks. However, no signs of new bone formation were found with the 200 microns pore size hydroxyapatite. In contrast, there was substantial production of bone within the 500 microns pore size implants at 12 and 26 weeks. Our results indicate that the pore size of the coralline hydroxyapatite influenced the development of bone in the implants in the cancellous bone bed of the rabbit femoral condyle. The results also show that spontaneous bone repair should be taken into consideration when the integration of implants is evaluated.

[Initial clinical results with heat-treated homologous bone transplants]. / Erste klinische Ergebnisse mit wärmebehandelten homologen Knochentransplantaten.

Several ways for HIV inactivation in bone allografts are being discussed. These methods must be efficient, but they must not compromise biologic properties of the allografts. According to animal studies, moderate heat treatment of bone allografts in a 65 degrees C waterbath has no adverse effects on osseointegration. A clinical follow-up study of 49 patients with heat treated bone allografts was conducted. 37 patients with conventional cryopreserved allografts were included in the study as controls. Average follow-up time was 27 months. Results were evaluated by clinical and X-ray examination, using a modified radiologic score. No significant differences in the two groups were detected, except for a slight retardation in bony integration of the heat treated allografts between week 39 and 52 postoperatively. Complication rates were 11.4% vs. 10.7%. In conclusion, moderate heat treatment of bone allografts appears to be a practicable and safe method to improve safety in bone transplantation in clinical practice. In addition to the known guide lines for bone banking heat treating of allografts should be further improved in order to minimize the low remaining risk of infection which exists despite of the three months test.

[Results of surgical treatment of posterior knee instability]. / Ergebnisse der operativen Behandlung posteriorer Knieinstabilitäten.

A retrospective study was performed to evaluate the outcome of operative treatment of posterior cruciate ligament (PCL) lesions in 115 patients operated on between 1980 and 1989. Follow-up was possible in 89 patients at 18-124 months postoperatively (average 76 months). In 65 re-examination was possible, while 24 patients returned a questionnaire. The results of patients who were operated on in the acute state were superior to those with chronic instabilities (Lysholm 79.9 +/- 18.5 vs 64.3 +/- 22.1; Tegner 5.7 +/- 2.3 vs 4.2 +/- 2.2; instrumented posterior drawer 5.3 +/- 3.5 mm vs 5.9 +/- 3.8 mm). On the other hand, the preoperative scores of symptomatic patients with chronic instabilities (Lysholm 38.8 +/- 22.0; Tegner 2.1 +/- 1.7) were clearly lower. Extraarticular procedures (Hughston) slightly improved symptoms in posterolateral instabilities. Olecranization of the patella had no influence on the results. Interpretation of the data is difficult as there was no matched group of patients with nonoperative treatment. A reviews of the literature suggests that isolated PCL tears are best treated with conservative management. Only in cases where associated ligamentous injuries require operative treatment should PCL reconstruction be performed. Chronic posterior instabilities should be treated operatively only if the patients are severely symptomatic. However, complete restoration of knee stability was usually not achieved with the techniques presented in this paper.

[Possibilities for HIV inactivation in homologous bone transplants]. / Möglichkeiten zur HIV-Inaktivierung homologer Knochentransplantate.

Recently, the availability of bone allografts has declined dramatically, due to the three-month HIV test which is often difficult to obtain. Accordingly, there is a search for methods to inactivate HIV in bone allografts without compromising the biologic quality of the grafts. Chemical substances require long exposure and desorption times, to ensure that no toxic agents remain within the bone before actual transplantation. X-ray inactivation leads to complete loss of any osteoinductive properties of the allografts, according to some authors. In addition, the high doses that are necessary are difficult to apply. Autoclaving has been practiced in some instances, but all experimental results and some more recent clinical observations warn that osteoinductive properties of the allografts are lost during the autoclaving process. Lower temperatures (56 degrees C) are sufficient to warrant inactivation of HIV, and some experimental results and preliminary clinical observations indicate that moderate heat treatment of bone allografts in a water bath may become a useful method for virus inactivation of bone allografts.

[Primary suture of the anterior cruciate ligament. A critical analysis]. / Die primäre Naht des vorderen Kreuzbands. Eine kritische Analyse.

Recently some authors have claimed that primary repair of an acute tear in the anterior cruciate ligament will fail in the long run. A review of the literature reveals that this opinion is mainly based on an American study in 1976. However, the poor results presented in this study were never reproduced. The study is critically analyzed, and 14 more papers presenting successful primary reconstructions of the anterior cruciate ligament are discussed. Preserving proprioceptive structures may be an important advantage of this technique, as it is hypothesized that the anterior cruciate ligament functions as a significant sensory organ, not only providing proprioceptive information, but also initiating protective and stabilizing muscular reflexes. In conclusion, it is recommended that primary suture be used combined with intra-articular semitendinosus tendon augmentation for rapid rehabilitation in cases of acute tears in the anterior cruciate ligament.

[Initial stability of an implanted cement-canal prosthesis. Results in experimental studies on human cadaver femurs]. / Die Primärstabilität bei Implantation einer Zementkanalprothese. Ergebnisse experimenteller Untersuchungen an humanen Leichenfemora.

Upon implantation of a cement-canal prosthesis in the proximal femur in total hip replacement, the bone cement is injected through the prosthesis via a system of drill holes. A second system of drill holes is used in this endoprosthesis to drain the distal femoral space as well as the cavities within the cement layer which form when the cement is being injected. Since the cement pressure is sustained until the cement has cured, substantial penetration of the cement into the cancellous bone can be achieved by using low intra-medullary cement pressures. Using cadaveric human femurs, the initial stability in the trabecular intertrochanteric region was determined in pull-out experiments for three different curing cement pressures (0.5 bar, 1.0 bar and 1.5 bar). The results were compared to corresponding controls in which a conventional cementation technique was used. With respect to the contact area of the bone/bone-cement interface, the initial stability increased by the factor 2.8 (cement-curing pressure 0.5 bar), 3.7 (cement-curing pressure 1.0 bar) and 2.9 (cement-curing pressure 1.5 bar) compared to the control group.

[Distal finger joint destruction after frostbite in childhood]. / Fingerendgelenkdestruktion nach Erfrierung im Kindesalter.

Destruction of the DIP-joint and of the growth plate of the distal phalanx after frostbite is shown in the case of a 13-year-old boy. Clinical symptoms, therapy, and result of treatment are presented and literature reviewed.

[Blood lamination in bone cement--effect of cementing technique]. / Blutschlieren im Knochenzement--der Einfluss der Zementiertechnik.

The quality of the cement layer influences the long-term survival of cemented endoprostheses. However, blood and fluid laminations within the cement layer, which can form during implantation of endoprostheses, lead to the deterioration of bone cement. Since the bone cement is the weakest part in the construction consisting of prosthesis, bone and bone cement, further weakening of the bone cement should be avoided if possible. By means of in vitro studies, three different cementing techniques were tested, measuring quantitatively the amount of fluid within the cement layer after implantation. The least amount of fluid within the cement layer was found in the cement-canal technique, and the highest amount in anterograde cement injection. Retrograde cement injection led to intermediate values.

[Clinical course of a late aseptically loosened PCA hip prosthesis shaft]. / Verlaufsbeobachtung einer aseptischen Spätlockerung eines PCA-Hüftendoprothesenschaftes.

The surface of the proximal part of a PCA endoprosthesis stem in total hip replacement is structured with small beads to provide good conditions for bone ingrowth. The distal part of the stem has a smooth surface. For the mechanical fixation concept, this means anchorage of the proximal part and free axial mobility of the distal part of the prosthesis. We present a clinical case in which bone remodeling processes finally led to complete loosening of the prosthesis. The described mechanism of loosening could be reconstructed by radiological findings, bone scan, two digital subtraction arthrographies of the hip and by evaluation of the fibrous tissue formation around the stem after explanation. In this case, after an initial period of no measureable bone reactions, distal endosteal bone and proximal radiolucent space developed without loss of contact with the prosthesis. Later, a mechanical interruption between the proximal part of the prosthesis and bone occurred. There was no loosening of the distal part of the prosthesis at this time. Despite remarkable hypertrophy of the distal femoral bone, eventually the distal part of the prosthesis loosened so that a revision arthroplasty had to be performed. The described mechanism of loosening has not be proven to pertain to all such prostheses.

[Combined injury of the anterior cruciate ligament and the medial collateral ligament of the knee joint--results of two to six years follow-up of surgical treatment]. / Kombinierte Verletzung von vorderem Kreuzband und medialem Seitenband des Kniegelenks--Zwei-bis Sechs-Jahres-Ergebnisse der operativen Behandlung.

A retrospective study of 148 combined acute knee injuries with anterior cruciate and medial collateral ligament injuries was performed. Follow-up included 115 patients, 95 of whom were personally examined two to six years postoperatively. Proximal anterior cruciate ligament ruptures were treated with reinsertion in 96 patients, in case of intraligamentous lesions (44 times), augmentation with the semitendinosus tendon was performed. Medial collateral ligament lesions were explored during the operation. Reconstruction of intraligamentous ruptures was performed with sutures (120 times). Distal lesions were refixed with Burri plate or staple. A modified Ellison procedure was routinely performed. Postoperative treatment was cast-free and included immediate physiotherapy using a functional brace. Between the two groups with anterior cruciate ligament reinsertion and augmentation, no significant differences were observed in subjective evaluation (Lysholm score 85 vs. 88), activity level (Tegner score 5.5 vs. 5.4) or anterior stability (KT 1000 at 89 N 6.6 vs. 6.1 mm displacement). A clear pivot shift sign was noted in two knees with reinsertion and in none of the augmented group. Medial stability was reestablished almost completely, independent of the site of lesion or the reconstruction technique (average valgus movement at 30 degrees flexion 0.7+ vs. 0.5+ on injured/contralateral side). We conclude that reinsertion of femoral anterior cruciate ligament ruptures will reestablish anterior stability in most cases, although semitendinosus augmentation appears to give slightly more reliable results. Medial stability is gained by the site-depending reconstruction techniques. Whether intraligamentous medial collateral ligament lesions can be left alone with only the anterior cruciate ligament being reconstructed, cannot be answered by this study.

Bone-cement removal with the excimer laser in revision arthroplasty.

The excimer laser was thought to be an appropriate tool for the removal of bone cement without damaging the bone. However, due to its low ablation rate, its clinical use in total hip revision arthroplasty proved to be impossible. This experimental study was designed to evaluate the maximal ablation rate by adjusting the laser's parameters. Energy density, frequency, pulse duration, radiation area, quantity of pulses, and environmental conditions were varied in the experimental setup. Even with the best set of parameters the excimer laser was about ten times slower than, e.g., the carbon dioxide laser. The removal of 10 g bone cement takes about 1 h. Thus, complete cement removal by means of the excimer laser alone is not possible. However, selective application of the excimer laser in combination with other techniques could be discussed.

Moderate heat treatment of bone allografts. Experimental results of osteointegration.

The use of bone allografts is often essential in orthopedic surgery. Strict donor screening, including HIV testing 3 months postoperatively, is mandatory before a transplant may be used. Yet these measures do not definitely rule out the possibility of HIV transmission, as there is a window period before infection is revealed by blood testing. Accordingly, there is a need for virus inactivation methods that can be used on bone allografts. As radiation treatment and chemical methods have a number of disadvantages, we chose a moderate heat treatment of 65 degrees C for a series of animal experiments. In 12 rabbit femoral condyles, moderate-heat-treated bone allografts were implanted into 6-mm drill holes. Twelve normal allografts and 12 empty drill holes served as controls. Radiologic and histological evaluation up to 12 weeks postoperatively revealed slow spontaneous bone remodeling from the rim to the center of the empty cavities. Normal deep frozen allografts were quickly intergrated after a short period of osteoclast reaction around the transplant, with occasional bone bridges between host and allograft. The examination of heat-treated allografts showed no differences to the controls, including morphologic aspects and the time course of osteointegration. Five zones of bone repair and osteointegration were distinguished. We conclude that thermal treatment of bone allografts has adverse effects on osteointegration in the rabbit femoral condyle. Thus, it may contribute to improving safety in human bone transplantation.