J. Forst
RWTH Aachen University
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Featured researches published by J. Forst.
Archives of Orthopaedic and Trauma Surgery | 1998
J. Forst; Raimund Forst; K. D. Heller; G. Adam
In 16 patients with an average age of 61.6 ± 9.8 years and sudden onset of severe knee pain, the initial stage of Ahlbäck disease (spontaneous osteonecrosis of a femoral condyle) was verified by magnetic resonance imaging (MRI) and subsequent histology. The first radiological sign of osteonecrosis (flattening of the affected femoral condyle) was present in only one case. All patients were treated surgically by extra-articular drilling into the affected femoral condyle to achieve core decompression. The knee pain disappeared immediately after surgery in all patients. Successful healing was confirmed by normalization of the bone marrow signal on MRI (on average, 35.8 months follow-up). Core decompression by extra-articular drilling into the femoral condyle can be recommended as an effective treatment in initial osteonecrosis of the knee (still radiologically invisible). However, if radiologically a flattening of the affected femoral condyle becomes apparent, progression of this disease cannot be avoided.
Neuromuscular Disorders | 1999
J. Forst; R Forst
Two hundred and thirteen of 428 patients with Duchenne muscular dystrophy (DMD) of a prospective and open study were operated on bilaterally with hip and knee release, aponeurectomy of the iliotibial band and Achilles tendon lengthening. In 87 patients the operation was carried out during early restrictions of the lower limb joint mobility at an average age of 6.56 years (4.02-8.26, SD 1.42). The follow-up was on average 5.4 years (0.25-9.01, SD 2.7). This group was compared to a control group (natural history) consisting of 100 non-operated DMD patients. A significant (P < 0.001) release of the contractures could be obtained. Loss of walking ability occurred in the control group at an average of 9.29 years (5.85-13.63, SD 1.98) and in the operated group at an average of 10.55 years (8.17-14.39, SD 1.76). This shows that early lower limb surgery leads to a prolongation of independent ambulation of 1.25 years on average. In contrast to the patients of the control group all treated patients between ages 6 and 8 years could walk independently. The positive influence of early lower limb surgery could also be shown by the development of Hammersmith motor ability score, CIDD (Council of Investigation of Duchenne Dystrophy) grading and Vignos scale. Nevertheless, in consideration of the well-known course of DMD not only the prolongation of ambulation but also the achieved prolongation of assisted standing ability with no or mild contractures are aims of lower limb surgery. Since no improvement of muscle strength could be observed after lower limb surgery, further studies have to investigate if additionally administered steroids can prolong ambulation after early lower limb surgery.
Foot & Ankle International | 1995
Raimund Forst; J. Forst; K. D. Heller
Ruptures of tibialis anterior tendon can be caused by open, closed, direct, or indirect trauma, as well as spontaneously. Sixty-three cases of tibialis anterior tendon ruptures have been reported in the international literature. The treatment of choice is the surgical end-to-end or side-to-side anastomosis after previous Z-lengthening. The case of a 28-year-old world-class female triathlete who sustained an open laceration of the tibialis anterior tendon from the bicycle chain guard is reported. The primarily applied tendon suture became infected and a wound revision with wide resection of the tendon stumps was necessary. This lead to an extensive defect of the tendon combined with a deep-seated keloidal scar reaction of the skin. The surgical closure was performed using free ipsilateral peroneus brevis tendon grafting. Four months after the operation the patient was completely rehabilitated. Eight months later she became the second European triathlon champion.
Archives of Orthopaedic and Trauma Surgery | 1999
J. Forst; S. Wolff; P. Thamm; Raimund Forst
Abstract A prospective randomized trial in 42 patients undergoing elective total hip or knee arthroplasty under general anaesthesia was carried out to evaluate the efficacy of patient-controlled analgesia (PCA) versus demanded conventional pain therapy (CPT) for controlling postoperative pain. Four patients had to be excluded from the study (2 postoperative confusion, 1 elevated piritramid dosage caused by chronic pain therapy, 1 stressed by PCA pump handling). PCA group (n = 19) received piritramid via PCA pump, CPT group (n = 19) received tramadol (oral or intramuscularly) or piritramid intravenously. PCA or CPT was started in the intensive care unit. Pain was measured with a standard 100 mm visual analogue scale (VAS) for 60 h postoperatively. Over this period of time, no significant differences were found in the pain score of both groups, nor did the incidence of side-effects differ significantly. The PCA group required on average twice as much piritramid-equivalent than the CPT group (P < 0.001). Patient satisfaction was good in both groups, but significantly better in the PCA group (P < 0.01), although the measured postoperative individual pain scores were above the preoperatively determined individual subjective pain threshold in the majority of both groups. From these results we draw the conclusion that even if the patients feel satisfied by the pain therapy administered, the majority are objectively treated below their individual subjective pain threshold.
Archives of Orthopaedic and Trauma Surgery | 1994
K. D. Heller; J. Forst; Raimund Forst; B. Cohen
Posterior dislocation of the should is rare, constituting only 2.1% of all shoulder dislocations. The mechanisms of injury may be due to direct or indirect forces, and constitutional predisposing factors also play a role. Anatomically, 97.5% of dislocations are subacromial. Three hundred articles published in the international literature concerning posterior shoulder dislocation and subluxation were reviewed and a classification determined by the underlying aetiology was developed. On this basis dislocations and subluxations may be traumatic or atraumatic, primary and recurrent; recurrent cases of voluntary dislocation are considered separately. In addition, a follow-up assessment score weighted towards stability of the shoulder after treatment is detailed.
Neuromuscular Disorders | 1998
J. Forst; R Forst; H Leithe; N Maurin
Platelet function and plasmatic coagulation of 51 patients with Duchenne muscular dystrophy (DMD) were studied in order to find an explanation for the known substantial blood loss in spinal surgery of these very patients. A normal plasmatic coagulation and a slight but not significant increase of bleeding time was found. However, a significant deficiency of platelet adhesion and ristocetin induced aggregation (P < 0.001) as well as a marked reduction of expression of glycoprotein i.v. (synonyms: GPIV, GPIIIb, CD36) to 50% were detected. We conclude from our study, that this finding of deficiency of platelet function in DMD patients is of no importance in everyday life and minor operations, e.g. lower limb surgery. In major spinal surgery, however, the platelet function deficiency occurs. A decompensation of platelet adhesion as well as aggregation capacity can be assumed due to the unavoidable intraoperative dilution effect by the inevitable volume replacement.
Neuromuscular Disorders | 1999
Jian-Feng Wang; J. Forst; Sebastian Schröder; J. Michael Schröder
Clinical improvement following surgery in patients with Duchenne muscular dystrophy (DMD) may be influenced by the severity of muscle fiber damage. This study correlates morphometric alterations of muscle fiber types, severity of fat tissue proliferation and fibrosis with Western blots, multiplex polymerase chain reaction (PCR), and postoperative state in DMD. The main results of this study show that the mean diameter of type 2 fibers is usually markedly larger than that of type I fibers in DMD although the number of type 2 fibers is severely reduced. The mean percentage of the remaining type 1 fibers was in the range of 57-82%. The morphometric and histopathological results were in agreement with the clinically estimated postoperative state, especially in the patients who presented a severe state or suggestive clinical improvement. It is concluded that combination of both quantitative and qualitative evaluation of muscle biopsies is suitable for better evaluation of the postoperative state in patients with DMD, whereas severity of exon deletions correlated poorly with morphometry and postoperative clinical state.
Archives of Orthopaedic and Trauma Surgery | 1997
J. Forst; C. Forst; Raimund Forst; K. D. Heller
The etiology of inborn hip dysplasia is unknown. In general, a multifactorial genesis is assumed. The influence of hormones on the development of the fetal hip joint and its stability is discussed as well as mechanical influences. This study was carried out with the intention to examine the correlation between the concentration of the pregnancy hormone relaxin and the stability of the hip joint in newborns. Both hips of 90 newborn children were examined clinically and sonographically. In 25 hips (13.9%), pathological sonograms according to the classification of Graf were found. The relaxin concentration was measured in cord blood using a heterologous radioimmunoassay. Statistical evaluation revealed an insignificant decrease of relaxin concentration with increasing sonographic hip instability. The results indicate that hip instability frequently occurs with decreasing relaxin concentration. These facts contradict the earlier assumption that hip instability coincides with increased relaxin concentrations in newborns. We assume that there is a worse preparation of the pelvis and the birth canal during pregnancy due to the lower relaxin concentration and thus that there could be a higher pressure on the fetus in the perinatal phase. A decreased relaxin concentration seems to have no direct effect on the hip joint tissue, but indirectly there is consequent rigidity of the tissue in mother and child, which
Ortopedia, traumatologia, rehabilitacja | 2011
Albert Fujak; Carsten Kopschina; Florian Gras; Raimund Forst; J. Forst
BACKGROUND Early development of contractures and progressive scoliosis with pelvic obliquity are the most significant orthopaedic problems for children with the intermediate form of spinal muscular atrophy, SMA type II. This study deals with the restrictions of the passive range of motion and the development of contractures of the lower extremities in these patients. PATIENTS AND METHODS We followed up 143 patients, 74 female and 69 male, with SMA type II for an average of 5.3 years (± 4.0, 0.2 - 18.7). Their average age at the first examination was 8.4 years (± 6.6, 0.1 - 34.1) and at the last examination 12.3 years (± 6.5, 0.7 - 37.1). The passive range of joint motion was determined using a goniometer. According to Johnson et al. (1992), we calculated the relative contracture index (CI). RESULTS The loss of range of motion (ROM) and the contractures of the joints of the lower extremities (hip, knee and ankle) develop early and increase progressively with age. Marked restriction of motion with severe flexion contractures in some cases was observed in the knee followed by the hip and ankle joint. CONCLUSION The findings of this study give us more information about the development of contractures and deformities of the joints of the lower extremities and aim to help to improve the quality of orthopaedic care of patients with SMA type II.
The Scientific World Journal | 2014
Gerrit Haaker; J. Forst; Raimund Forst; Albert Fujak
Introduction. Pompe disease (PD), a lysosomal storage disease as well as a neuromuscular disorder, is a rare disease marked by progressive muscle weakness. Enzyme replacement therapy (ERT) in recent years allowed longer survival but brought new problems to the treatment of PD with increasing affection of the musculoskeletal system, particularly with a significantly higher prevalence of scoliosis. The present paper deals with the orthopedic problems in patients with PD and is the first to describe surgical treatment of scoliosis in PD patients. Patients and Methods. The orthopedic problems and treatment of eight patients with PD from orthopedic consultation for neuromuscular disorders are retrospectively presented. We analyzed the problems of scoliosis, hip dysplasia, feet deformities, and contractures and presented the orthopedic treatment options. Results. Six of our eight PD patients had scoliosis and two young patients were treated by operative spine stabilization with benefits for posture and sitting ability. Hip joint surgery, operative contracture release, and feet deformity correction were performed with benefits for independent activity. Conclusion. Orthopedic management gains importance due to extended survival and musculoskeletal involvement under ERT. Surgical treatment is indicated in distinct cases. Further investigation is required to evidence the effect of surgical spine stabilization in PD.