Biomedical subjects

J Grifka

Publications and source records attributed to J Grifka.

At least 37 records · Page 2Linked to original sources

PubMed2005

Two-year follow-up on joint stability and muscular function comparing rotating versus fixed bearing TKR.

Mobile and fixed bearing in total knee replacement are still discussed controversially. In a retrospective, matched-pair study, we investigated 40 patients with computer-assisted (BrainLAB) primary total knee replacement (PFC Sigma, DePuy) performed two years before. Twenty patients each received a mobile bearing and a fixed bearing. We compared Womac Score, Knee Society Score, postoperative ROM, fluoroscopic measurement of knee stability in flexion and extension and isokinetic muscle strength using a Biodex-3 dynamometer. Both groups showed similar results concerning WOMAC Score (total rotating bearing: 23.05; fixed bearing: 22.57), KSS (rotating bearing: 174.89; fixed bearing: 176.1). Isokinetic muscle force demonstrated statistically significant superior results for knee flexion in the rotating bearing group. Medio-lateral stability revealed statistically significant superior results for the rotating bearing compared to fixed bearing in extension (P>0.05). In flexion only lateral stability was superior (P>0.05). Two-year clinical follow-up after computer-assisted total knee replacement resulted in good clinical outcome with high patient satisfaction. Statistically significant better values for the rotating platform group were found for the medio-lateral stability in extension and the peak flexion torque.

Aged↗

PubMed2005

Micromotion in cemented rotating platform total knee arthroplasty: cemented tibial stem versus hybrid fixation.

INTRODUCTION: Improving the longevity and reliability of cemented total knee arthroplasty (TKA) remains a major step to achieve. It is still unclear, whether a cemented tibial stem reduces micromotion of the tibial tray and produces therefore a better initial stability or not. The higher conformity of rotating platform design and the possible rotary forces to the tibial platform may produce higher micromotion when the tibial stem remains cementless (hybrid fixation). MATERIALS AND METHODS: An in vitro study was performed using the PFC mobile bearing tibial tray (DePuy, Warswa, IN, USA) to test the hypothesis that the addition of cement surrounding the tibial stem reduces micromotion of the tibial tray in cemented TKA with mobile bearing design. Ten tibial trays with mobile design were implanted in sawbones with a 3-mm cement mantle beneath the baseplate of the tibial tray and with or without the cemented stem. Tibial trays were loaded additionally in the ventral, lateral, medial and posterior positions with 2,500 N using the Zwick Z010 instrumentation and HBM pick up Hottinger Baldwin. RESULTS: In this study, a significant increased mean maximum liftoff was found when only cementing the tibial baseplate (hybrid fixation), compared to the fully cemented tibial tray (P<0.02). CONCLUSION: In conclusion, the stem of mobile bearing tibial components should be cemented to provide increased micromotion and earlier loosening.

Arthroplasty, Replacement, Knee↗

PubMed2005

Greater accuracy in positioning of the acetabular cup by using an image-free navigation system.

In a prospective and randomised clinical study, acetabular cups were implanted free-hand (control group n=22) or with computer assistance using an image-free navigation system (study group n=23). The cup position was determined postoperatively on pelvic CT. An average inclination of 42.3 degrees (range: 30 degrees -53 degrees ; SD+/-7.0 degrees ) and an average anteversion of 24.0 degrees (range: -3 degrees to 51 degrees ; SD+/-15.0 degrees ) were found in the control group, and an average inclination of 45.0 degrees (range: 40 degrees -50 degrees ; SD+/-2.8 degrees ) and an average anteversion of 14.4 degrees (range: 5 degrees -25 degrees ; SS+/-5.0 degrees ) in the computer-assisted study group. The deviations from the desired cup position (45 degrees inclination, 15 degrees anteversion) were significantly lower in the computer-assisted study group (p<0.001 each). While only 11/22 of the cups in the control group were within the Lewinnek safe zone, 21/23 of the cups in the study group were placed in this target region (p=0.003).

Acetabulum↗

PubMed2005

Eversion or subluxation of patella in soft tissue balancing of total knee arthroplasty? Results of a cadaver experiment.

Correct postoperative leg alignment and stability of total knee prosthesis over the full range of movement are critical factors for successful TKA. This is achieved by correct implantation of prosthesis and soft tissue handling. However, the surgical approach and how to displace the patella are still controversial. We have carried out a cadaver study looking at the effect of patella eversion or subluxation on limb axis alignment during balancing of the knee in three different standard surgical approaches; subvastus, midvastus, or medial parapatellar. For each approach, five knees were studied. Leg alignment was visualised by the Ci CT-free DePuy/BrainLAB navigation system. Using a navigation system alignment was determined in the AP axis in both extension and 90 flexion, with the patella everted as well as subluxated. Eversion of the patella gave a more valgus axis reading than subluxation in both extension 0.58 (SD: 0.03, range 0.54 -0.60 ) and 90 flexion 0.48 (SD: 0.11, range 0.38 -0.60 ). The effect was greatest using the medial paraptellar approach. Surgeons should be aware that everting the patella influences the AP alignment when soft tissue balancing in total knee replacement.

Arthroplasty, Replacement, Knee↗

PubMed2005

[What is the influence of the approach to intraoperative measurement of the knee joint on total knee arthroplasty? A navigation-controlled study on a cadaver knee].

Correct postoperative leg alignment and stability of the total knee prosthesis over the full range of movement is one critical factor for successful TKA. The anatomic approach is still the subject of controversy. The aim of our study was to elucidate the influence of the surgical approach on the ligament balancing and the anterioposterior limb axis.On five cadaver knees we studied the influence of the subvastus, midvastus, medial parapatellar, rectus snip, and tuberosity osteotomy approaches on the anterioposterior leg axis in extension and the rotation of the femoral component in flexion. Measurements were performed and documented by CT-free Ci-Navigation-System. Ligament tension was measured with a tensor device. We found that the subvastus approach leads to less widening of the medial compartment than all other approaches in extension. In 90 degrees flexion we found a similar influence. The consecutive release from subvastus to midvastus to medial parapatellar approach leads to a further opening of 0.5-1 degrees valgus in extension as well as in flexion. An everted patella amplifies this influence. The surgeon has to be aware of the impact on the ligament situation in regard to the anatomic approach when ligament balancing and soft tissue releases are carried out. Patella eversion should be avoided when managing soft tissues.

Arthroplasty, Replacement, Knee↗

PubMed2005

[Procedures for treatment of joint mechanics impairment in the rotating Endo-model knee prosthesis].

In cases of mechanical damage of the Endo model rotating knee prosthesis, it is not necessary to change the complete prosthesis. Isolated replacement of the mechanics is possible. We changed a sled prosthesis of a 66-year-old patient to a rotating knee prosthesis because of ligament instability. After the patient fell and traumatized the operated knee, she experienced pain during weight bearing and instability. Because clinical and fluoroscopic examinations verified instability of the prosthesis, we decided to change the mechanics of the rotating knee prosthesis. In conclusion, mechanical damage of a rotating knee prosthesis is a rare complication. Operative treatment is easy to manage if replacement parts and instruments to change the mechanics have been organized preoperatively.

Aged↗

PubMed2005

[Necrosis of the carpal scaphoid after chemotherapy. Case report].

Preiser's disease--first described by Preiser in 1910--presents the rare avascular necrosis of the carpal scaphoid. There is no consensus with regard to cause and therapeutic procedure to this day. The initially postulated idiopathic origin of the disease is controversial and rare. It is mainly caused by trauma or repetitive microtrauma, but can also occur as a complication of drug therapy. The rare occurrence of necrosis of the carpal scaphoid following chemotherapy is presented. The treatment was resection of the scaphoid and mediocarpal arthrodesis. Clinical appearance, diagnostic work-up, and therapy of the disease are discussed.

Antineoplastic Agents↗

PubMed2005

[Soft tissue management in knees with varus deformity. Computer-assisted sequential medial ligament release].

BACKGROUND: Knees with severe varus deformities and contractures of the medial and lateral collateral ligaments and the posterior capsule require special soft tissue management to gain a stable knee over the full range of movement. The introduction of navigation systems into knee surgery has now made precise measurement of the leg axis and gap size possible. METHODS: Ten knee joints received a computer-assisted total knee replacement (Ci navigation system DePuy) I-Orthopaedics, Munich). The change of the leg axis and the size of the mediolateral gaps were measured and documented when performing a standardized medial ligament release sequence. RESULTS: We found a significant effect after each release step regarding the change of the leg axis as well as the gap width (p<0.001). The highest effect was seen for the 6-cm capsule release in extension and the release of the medial collateral ligament in 90 degrees flexion. CONCLUSION: Implementation of computer-assisted navigation facilitates visualization and quantification of the effect of the sequential medial soft tissue release in total knee arthroplasty.

Arthroplasty, Replacement, Knee↗

PubMed2005

[CRPS type I psychological origin-case report].

The complex regional pain syndrome type I (CRPS I)-formerly named Sudeck's atrophy or reflex sympathetic dystrophy (RSD)-describes a complex of symptoms with chronic, poorly controllable pain, autonomic, sensomotor and trophic alterations. It is mainly caused by trauma or surgery. We describe the rare case of a spontaneous manifestation of a CRPS I in an adolescent patient with typical clinical and radiological findings and the recurrence of symptoms after a one-year symptom-free interval. Symptoms were resolved by an intense multimodal therapy concept. The likely psychosocial origin in this case is discussed. Clinical appearance, diagnostic means and therapy of the CRPS are described.

Adolescent↗

PubMed2005

[Efficacy of home exercises for symptomatic rotator cuff tears in correlation to the size of the defect].

AIM: Although the outcome of surgical treatment of rotator cuff tears is well documented in the literature, less is known about the efficacy of home exercises for symptomatic rotator cuff tears in correlation to the size of the defect. METHODS: A series of 30 patients (38 shoulders) with rotator cuff tears seen by ultrasonography were included in this prospective study. Rotator cuff tears were divided into partial defects (group A), full thickness tears of the supraspinatus tendon (group B), and massive rotator cuff defects (group C). Treatment consisted of a home program of stretching and strengthening exercises that were performed by the patients daily for a period of 12 weeks and controlled by a physician every 2 weeks. Range of motion, a modified constant score, and impingement signs at initial examination and after 12 weeks were compared. RESULTS: All groups experienced improvement in range of motion. The Constant scores improved significantly (p < 0.05) in all groups (A: 13.0 [+/- 7.9 SD], B: 13.2 [+/- 11.4 SD], and C: 17.5 [+/- 6.6 SD]). Impingement signs showed a downward trend in all groups. DISCUSSION: The results of this study show that patients with rotator cuff defects do benefit from simple home exercises independent from the size of the defect.

Adult↗

PubMed2005

[Ultrasound evaluation of the acromioclavicular joint. A comparison with magnetic resonance imaging].

INTRODUCTION: Ultrasound is useful in detecting acromioclavicular pathologies in cases of trauma, inflammations and degenerative changes in sports medicine. Many studies compare joint space and capsular dimensions of symptomatic and asymptomatic patients. However, no study has examined the reproducibility and reliability of these measurements. The aim of this study was to evaluate the reliability of ultrasonographic measurements in assessing the acromioclavicular joint. MATERIALS AND METHODS: 27 acromioclavicular joints of 15 healthy subjects were examined by T1 weighted magnetic resonance imaging (MRI) to determine the normal limits of joint space (a) and joint capsule (b). These measurements were compared to standardised ultrasonographic (11 Mhz) measurements, which were repeated three times. RESULTS: The mean difference between MRI and ultrasound measurements was 1.5 +/- 1.3 mm and 1.3 +/- 1.2 mm for distance a and b, respectively. Reproducibility of ultrasonographic measurements was high with a mean standard deviation of 0.3 +/- 0.2 mm and 0.4 +/- 0.3 mm for distance a and b, respectively. CONCLUSION: Due to low costs, safety and wide availability ultrasonography is suited for the evaluation of the acromiocalvicular joint. However, when interpreting the results measurement errors, limitations in resolution of the system used, and the anatomy of the acromioclavicular joint and its anatomic variants have to be taken into consideration.

Acromioclavicular Joint↗

PubMed2005

Efficacy of etoricoxib 60 mg/day and diclofenac 150 mg/day in reduction of pain and disability in patients with chronic low back pain: results of a 4-week, multinational, randomized, double-blind study.

BACKGROUND AND METHODS: The efficacy and safety of etoricoxib 60 mg/day in patients with established chronic low back pain (CLBP) were compared with those of diclofenac 150 mg/day in a 4-week, multicentre, randomized, double-blind, parallel-group trial. Four hundred and forty-six adult patients with CLBP (Quebec Task Force on Spinal Disorders Class 1 or 2) and with worsening pain upon discontinuation of pre-study analgesic medication were enrolled in the study. The study primary efficacy endpoint was change from baseline in Low Back Pain Intensity Scale (LBP-IS) score over the 4-week treatment period. Secondary and other efficacy endpoints included: changes in Roland and Morris Disability Questionnaire (RMDQ), Patient Global Assessment of Response to Therapy (PGART) and Low Back Pain Bothersomeness Scale (LBP-BS) scores. Early efficacy was assessed using PGART and LBP-IS scores 4 h after the first dose on the mornings of Days 1, 2 and 3. The overall safety and tolerability of etoricoxib 60 mg/day during 4 weeks of treatment were also assessed. RESULTS: The least-squares mean time-weighted change from baseline LBP-IS score over 4 weeks was -32.94 mm (95% CI -36.25, -29.63) for etoricoxib, indicating substantial efficacy in relief of pain. The treatment difference for the primary outcome was 2.51 mm (95% CI -1.50, 6.51), fulfilling the prespecified equivalence criterion of 95% confidence interval wholly within +/- 10 mm. Etoricoxib improved all secondary and other efficacy outcomes. There were no statistically significant between-group differences in the proportion of patients with one or more clinical adverse events (AEs) (etoricoxib 35%, diclofenac 39%), or the proportion of patients who discontinued due to AEs (etoricoxib 7%, diclofenac 5%). CONCLUSIONS: The results of this study confirm that, for adult patients with CLBP, etoricoxib 60 mg once daily over 4 weeks is effective for relief of pain and improvement of physical function and comparable to high-dose diclofenac 150 mg daily.

Adult↗

PubMed2004

Intraoperative cutting errors in total knee arthroplasty.

INTRODUCTION: Precise reconstruction of leg alignment offers the best opportunity for achieving good long-term results in total knee arthroplasty (TKA). It was the aim of this study to evaluate the bone-cutting process as a potential source of inaccuracy in TKA. MATERIALS AND METHODS: In a consecutive series of 50 computer-assisted TKAs, cutting errors, which were defined as a difference between the cutting block position before sawing and the achieved resection plane afterwards, were measured for the distal femur and proximal tibia resection. Measurements were performed using a CT-based navigation system. RESULTS: For the distal femoral cut, there was a mean varus/valgus deviation of 0.6 degrees (SD+/-0.5 degrees ) and a mean flexion/extension deviation of 1.4 degrees (SD+/-1.3 degrees ). For the proximal tibia, varus/valgus alignment showed a mean deviation of 0.5 degrees (SD+/-0.5 degrees ). The mean sagittal variability was 1.0 degrees (SD+/-0.9 degrees ). Differences between the frontal and the sagittal plane were significant. CONCLUSION: To minimize cutting errors, techniques and instruments are needed which enable a more stable fixation of the cutting blocks or even more appropriate preparation instruments. Using a computer-assisted technique, the surgeon is aware of cutting errors occurring at each point of the operation and will therefore be able to correct these errors during surgery, while he is not aware of those errors with the conventional TKA technique.

Adult↗

PubMed2004

Flexion gap configuration in total knee arthroplasty following high tibial osteotomy.

Previous reports have described the potentially compromising effect of a high tibial osteotomy (HTO) on the results of a subsequent total knee arthroplasty (TKA). Although the reasons are not clear, some authors reported problems in soft-tissue balancing. In a prospective study, 22 patients with an average interval of 5.8 years after closed-wedge HTO were operated for TKA. All operations were performed with a CT-free navigation system, and measurements of the extension and flexion gap were assessed. The intraoperative data were compared to a control group of 100 consecutive computer-assisted TKA without previous osteotomy. In the study group, a highly significant shift towards a medial opening of the flexion gap between the posterior condylar line and the tibial resection (study group 0.4+/-4.7 degrees medial opening versus control group 3.4+/-3.3 degrees lateral opening, p<0.001) was observed. In the study group, 10/22 showed a medial opening of the flexion gap compared to 11/100 in the control group. Surgeons should be aware of difficulties in soft-tissue balance in TKA following HTO, especially for the flexion gap configuration and the axial rotation of the femoral component.

Aged↗

PubMed2004

Minimally invasive unicompartmental knee replacement with a nonimage-based navigation system.

In a prospective study, two groups of 20 unicompartmental knee replacements (UKR) each were operated either using a CT-free navigation system or the conventional minimal invasive technique. Radiographic assessment of postoperative alignment was performed by long-leg coronal and lateral radiographs. The results revealed a significant difference between the two groups in favor of navigation. In the computer-assisted group, 95% of UKRs were in a range of 4-0 degrees varus (mechanical axis) compared with 70% in the conventional group. The only inconvenience was a prolonged operation time (+19 min). Due to the limited exposure, the navigation system is helpful in achieving a more precise component orientation. The danger of overcorrection is diminished by real-time information about the leg axis at each step during the operation.

Aged↗

PubMed2004

Radiological results of image-based and non-image-based computer-assisted total knee arthroplasty.

Restoration of the mechanical limb axis and accurate component orientation are two major factors affecting the long-term results after total knee replacement (TKR). Different navigation systems are available to improve the outcome. Image-based systems require pre-operative CT scans, while non-image-based systems gain all necessary information intra-operatively during a registration process. We studied 130 patients who received a TKR either using the CT-based (Knee 1.1) or the CT-free module (CT-free Knee 1.0) of the BrainLAB Vector-Vision Navigation System. Post-operative leg alignment and component orientation was determined on long-leg coronal and lateral X-rays. Sixty of 65 patients in the CT-based group and 63/65 patients in the CT-free group had a post-operative leg axis between 3 degrees varus/valgus. No significant differences were found for varus/valgus orientation of the femoral and tibial components.

Aged↗

PubMed2004

[An update on thrombosis prophylaxis in orthopaedic and accident surgery].

The prevention of deep venous thrombosis has become a routine in orthopaedic surgery. While the necessity for prophylaxis is not questioned, its practice is still a matter of controversy. The development of new anticoagulants increases the variety of prophylactic methods but leads to a need for additional information. This review deals with the indications for thrombosis prophylaxis in relation to exposing and predisposing risk factors. The currently available modalities of prophylaxis, their pharmacological details and clinical significance are presented. Evidence based data, recommendations on the duration of prophylaxis derived from official guidelines, issues of the cost/effectiveness, and medico-judicial aspects are discussed.

Anticoagulants↗

PubMed2004

[A synopsis of medication for degenerative osteoarthritis].

Drug treatment options should be used before starting operative procedures for degenerative osteoarthritis. The directed use of drugs helps to convert activate arthritis to the asymptomatic phase. This article summarizes guidelines and gives an overview of the effects and problems.

Adrenal Cortex Hormones↗