Ralf H. Wittenberg

Biomechanical properties of resorbable poly-L-lactide plates and screws: A comparison with traditional systems

Poly-L-lactide (PLA) plates and screws were tested in vitro in porcine ribs for uniaxial pullout and four-point bending strength. Results were compared to conventional systems (stainless steel and titanium). The biomechanical testing suggests that PLA screws have properties suitable for fixation of sagittal split osteotomies. Poly-L-lactide plates have indications in areas of low stress and noncompressive load.

Prostaglandin release from lumbar disc and facet joint tissue.

Objectives The authors measured prostaglandin (PG) and leukotriene (LT) release from human disc and lumbar facet joint tissues. Summary of Background Data High levels of phospholipase A2 (PLA2) have been measured in the human disc. PLA2 releases fatty acids from lipid membranes. These can be converted to PG and LT, which are potent inflammatory mediators and supposed to be involved in lumbar diseases. Methods The tissues were obtained during surgery and incubated in Tyrodes solution. PG and LT release was measured radioimmunologically from the supernatant. Results Disc (4 ng/g wet weight), cartilage (21 ng/g wet weight), and bone (14 ng/g wet weight) released PGs but no LTs. Conclusion Because PG release from sequestrated disc is rather low, the inflammatory effect might be more because of immunologic reactions.

Surgical or conservative treatment for chronic rotator cuff calcifying tendinitis – a matched-pair analysis of 100 patients

Abstract Conservative or operative treatment for rotator cuff calcifying tendinitis was investigated in 100 patients in a matched-pair analysis. They were examined clinically and ultrasonographically 35–60 months after the initial visit. The mean Patte score was 91.8 for the patients who underwent surgical treatment and 81 for the ones who received conservative therapy (p < 0.004), while the age-related Constant-score was 103.4 and 95, respectively. Ultrasonography showed 28% calcifications in the surgical group, 18% newly formed and 10% that did not resolve after surgery. In the conservatively treated group, 33% calcifications were seen, of which 67% resolved. The number of rotator cuff ruptures was significantly higher in the conservative group. In the surgical group, 2% of partial tears and in the conservative group 5% of partial and 4% of complete cuff ruptures were found. Conservative treatment for calcifying tendinitis leads to less favourable pain results in the long term than surgical treatment. Surgery shortens the painful period and may reduce the number of future rotator cuff ruptures. Finally, the subjective functional outcome is significantly better after surgery.

Prospective randomized surgical treatments for calcifying tendinopathy

Thirty-eight patients with chronic calcifying tendinopathy of the shoulder were randomized prospectively into two groups: 19 patients had endoscopic decompression and 19 had open decompression. Thirty-three patients (19 with open and 14 with endoscopic decompression) were available for followup. Clinical and ultrasonographic investigations were done at followup. The purpose of the current study was to evaluate prospectively the clinical and sonographic results after open decompression and after endoscopic decompression. Apportionment of age and gender was similar in both groups. The followup was 15.7 months for patients after open decompression and 17.1 months for patients after endoscopic decompression. The average Patte score was 84.5 points (84.4 for patients who had endoscopic decompression and 84.6 for patients who had open decompression). Corresponding results were found with a Constant and Murley score of 96.6 points (97.6 for patients who had endoscopic decompression and 95.8 for patients who had open decompression). In the endoscopic group physiotherapy was recommended for 5 weeks more than in the open surgery group. Similar results were seen for the incapacity to work in both groups with 4.6 weeks for the patients who had endoscopic surgery and 5 weeks for the patients who had open surgery. No nerve injuries, wound infections, or other postoperative complications were found. Comparison of both surgical methods showed good clinical and score results. Endoscopic and open surgery are equally effective in the treatment of chronic calcifying tendinopathy.

Local anaesthetic injection with and without corticosteroids for subacromial impingement syndrome

Abstract Fifty patients with impingement syndrome refractory to long-term conservative treatment were randomized to three treatment groups. All patients received an injection of 10 ml 0.5% bupivacaine, in group 1 without corticosteroid, in group 2 with crystalline corticosteroid and in group 3 with lipoid corticosteroid. Treatment in group 1 had to be stopped because of inefficacy. In groups 2 and 3 favorable results were achieved in 19 out of 40 patients.Résumé 50 patients avec conflit sous-aeromial, qui ne montraient pas d’amélioration après un long trâitement conservatif récevaient une injection dans la bourse subacromiale. Le premier groupe récevait une injection contenant un anaesthétique local pur, groupe 2 une mixture d’anaesthétique avec des corticostéroides cristalins et groupe 3 avec des corticostéroides lipoides. Le trâitement du groupe 1 devait être arrété cause d’inificacité. 19 de 40 patients du groupe 2 et 3 montraient une amélioration après 6 mois.

Five-year results from chemonucleolysis with chymopapain or collagenase: a prospective randomized study.

Study Design. A 5-year clinical follow-up assessment of a prospective randomized study of chemonucleolysis using chymopapain (4000 IU) or collagenase (400 ABC units) was performed. Summary of Background Data. Intradiscal therapy can be performed for patients with contained discs by chemonucleolysis, percutaneous discectomy, or laser ablation. The oldest intradiscal therapy is chemonucleolysis with chymopapain. Objective. The purpose of this study was to compare prospectively the efficacy of chymopapain and collagenase for intradiscal injection. Methods. In this study, 100 patients with indication for intradiscal therapy were prospectively randomized to treatment with either chymopapain or collagenase. All the injections were performed by the double-needle technique with the patient under general anesthesia. The mean age of the patients was 35.5 years in the chymopapain group and 38 years in the collagenase group. An equal number of injections was performed at L4–L5 and L5–S1. Results. After 5 years, good and excellent results were observed in 72% of the chymopapain group and 52% of the collagenase group when the surgically treated and lost patients were graded as poor. Using a scale of 0 (no pain) to 10 (intractable pain), the pain level dropped from 8.5 to 0.7 in the chymopapain group and from 8.6 to 0.9 in the collagenase group. Microdiscectomy at the injected level was required for 23 patients (14 in the collagenase group and 9 in the chymopapain group). Conclusions. After 5 years, no deterioration had occurred, as compared with the 1-year follow-up assessment. Chymopapain has proved to be safe, with one minor anaphylactic reaction, and effective even over the long term. Collagenase may need further study and cannot be recommended at this time.

Five-year results of a cementless short-hip-stem prosthesis

Hip prosthesis stems with a short stem length and proximal fixation geometry support a bone-preserving and muscle-sparing implantation and should also allow for revision surgery with a standard hip stem. We present 250 prospectively documented clinical and radiological results from the Metha Short Hip Stem prosthesis (B. Braun-Aesculap, Tuttlingen, Germany) after an average follow-up of 4.9 years. The average patient age at surgery was 60 years. Indication for total hip replacement was primary osteoarthrosis (OA) (78% of patients), OA based on developmental dysplasia of the hip (16%), and other indications (6%). At the last follow-up, the average Harris Hip Score was 97 points. 85% of patients were very satisfied and 14% were satisfied after surgery, whereas 1% were dissatisfied. Pain according to the Visual Analogue Scale improved from 7.4 (min 1.6, max 9.5) pre-operatively to 0.23 (min 0, max 6.6). No joint dislocations occurred when predominantly using 28 mm and 32 mm prosthesis heads. Nine short-stems were revised: three after bacterial infections, two after primary via valsa with penetration of the femoral cortex two and three months after surgery, and three after early aseptic cases of loosening within the first year. A further nine osseously consolidated short-stems had to be replaced due to breakage of the modular titanium cone adapter after an average of 3.1 years (min 1.9, max 4.4). All surgical revisions were performed using primary standard stems. Without taking the material-related adapter failures into account, a five year Kaplan-Meier survival rate of 96.7% (95% confidence interval 93.4–98.3) was determined for the short-stem prostheses. There were no radiological signs of loosening in any of the short-stem prostheses at the last examination. Fine sclerotic lines were detected in Gruens AP zones 1 (19%) and 2 (10.5%), individual hypertrophies in zone 3 (3.5%), fine seams in zones 4 (5.5%) and 5 (4%), without pedestal formations in zone 4, clear cancellous bone compressions in zone 6 (97.5%), as well as single fine scleroses (1.5%) and atrophies (2.5%) in zone 7. The mid-term clinical results with periprosthetic bone remodeling and without radiological signs of loosening confirm this metaphyseal short-stem treatment and fixation concept and the possibility of revision surgery using standard hip stems. Long-term results must be further observed on a prospective basis as part of this collective study.

Noncontiguous Unstable Spine Fractures

Study Design. Evaluation of 1054 patient charts and 100 random roentgenogram charts as well as clinical investigation of 39 patients. Objectives. Noncontiguous unstable spine fractures are rare, easy overlooked, and difficult to treat. The purpose of the study was to evaluate the delay in diagnosis and clinical and radiologic outcome of these fractures. Summary of Background Data. Noncontiguous spine fractures are reported in about 1.6–16.7% in the literature. In most of the studies stable fractures, which did not need any special treatment, were also included. Therefore, in this study only unstable fractures requiring treatment were reinvestigated. Methods. A total of 1054 patients with fractures of the spine were treated over a period of 14 years in the spinal cord injury unit and retrospectively reviewed; 141 (13.4%) of the patients had multiple fractures, but only 39 (3.7%) had a noncontiguous spine fracture, most frequently from a fall or jump from a greater height, or traffic accidents. Results. Thirty patients (76.9%) had all fractures diagnosed at the first examination. Nine patients (23.1%) had a delayed diagnosis of the secondary lesion, but this delay resulted in no neurologic deterioration. A total of 32 extraspinal injuries were diagnosed and treated 14 times surgically. Loss of correction was seen after surgical treatment (n = 21), and increasing deformity occurred after conservative treatment (n = 18). The neurologic deficit improved in 10 conservatively (4) and operatively (6) treated patients and deteriorated in one patient after surgery. Conclusion. A delayed diagnosis of the second fracture was frequently seen without clinical consequences, and neurologic improvement occurred after conservative and operative treatment. Surgical treatment resulted in significantly earlier mobilization and less kyphotic deformity.

The correlation between magnetic resonance imaging and the operative and clinical findings after lumbar microdiscectomy

Abstract. Fifty-four consecutive patients were studied prospectively with magnetic resonance imaging before microdiscectomy, and the findings correlated with clinical symptoms before and after operation. A sequestrated fragment was found in 59% of cases, a subligamentous disc sequestration in 25% and a disc protrusion in 16%. The levels operated on were L4/5 – 36%, L5/S1 – 62.5%, and one at L3/4; 71% were laterally placed, 10% lay intraforaminal and 10% medial. The diameter of the protrusion was 4 mm to 13 mm for the craniocaudal extension, and 5 mm to 18 mm for the anteroposterior extension. No correlation could be found between a neurological deficit and the size of the prolapse. A positive correlation was present between the increasing degree of canal obstruction and the degree of disc degeneration determined by imaging for extrusions, subligamentous disc sequestrations and free sequestrations. Nerve root inflammation and enlargement was seen in 36% of the images, corresponding to an operative finding of 32%. Magnetic resonance imaging is a helpful preoperative diagnostic investigation which shows structural changes in the disc and the correct localisation and size of the disc sequestration, but there was no correlation between the imaging findings and the clinical symptoms.Résumé.Dans une étude prospective 54 patients d’un âge moyen de 41 ans ont été examinés avant une microdiscectomie au moyen d’un protocole IRM standardisé. Les résultats de l’IRM ont été mis en corrélation avec les symptomes cliniques avant et après chirurgie et les constatations operatoires. 59% des patients avaient un fragment libre, 25% un séquestre sous-ligamentaire du disque et 16% une protrusion du disque au niveau L4/5 (36%) ou L5/S1 (62%) et aussi une au niveau L3/4. 71% de celles ci étaient situées médiolatéralement, 10% latéralement ou intraforaminal et 10% seulement avaient une localisation médiale. Les diamètres de la protrusion discale variaient de 4 à 13 mm pour l’extension craniocaudale et de 5 à 18 mm pour l’extension antério-postérieure. Aucune corrélation entre un déficit neurologique et la taille du prolapse discal ont été trouvée. Une corrélation existe entre le degré d’augmentation de l’obstruction du canal et le degré de la dégénération du disque déterminéà l’aide du l’IRM pour les extrusions, les séquestres sous-ligamentaires et les séquestres libres. L’inflammation et l’agrandissement de la racine du nerf se montraient dans 36% des IRM correspondant à 32% intra-opèra- toires. Le IRM est une technique diagnostique importante préoperative pour permettre la localisation correcte, et pour une prévision de la grandeur de la séquestration disquaire. Il n’existe pas de corrélation entre le IRM et les symptomes cliniques.

Antiinflammatory effect of tepoxalin Blood and synovial tissue studied in patients with knee arthrosis

Our aim was to determine the amounts of eicosanoids in blood and synovial tissue of patients with knee arthrosis and to examine the effects of 2 doses of tepoxalin (50 mg twice, 200 mg twice), administered p.o. for 3.5 days. Concentrations of leukotriene B4 (LTB4, LTC4, and thromboxane B2 (TXB2) were measured in blood before and after oral administration of tepoxalin and release of prostaglandin E2 (PGE2), 6-keto-PGF1alpha, and LTC4 was measured in incubation media of synovial tissue, taken at surgery from patients treated with tepoxalin. Radioimmunoassay (RIA) was used to determine the levels of the eicosanoids. LT and TXB2 release was reduced by tepoxalin in both doses used. Under these conditions, PGE2, 6-keto-PGF1alpha, and LTC4 release from synovial tissue was detectable only after stimulation with calcium ionophore A23187. Washed synovial tissue, in which tepoxalin concentrations should be reduced, released higher amounts of all eicosanoids measured than directly incubated synovial tissue did. Pain after tepoxalin administration was significantly reduced. Relevant drug concentrations were detected in plasma and synovial fluid. Tepoxalin was well tolerated and had no marked adverse effects. At 400 mg, tepoxalin is a dual inhibitor of cyclooxygenase (CO) and 5-lipoxygenase (5-LO) in blood and synovial tissue.