Eirik J Solheim

Abstract: PURPOSE: The objectives of this study were to evaluate the results in the outpatient treatment of recalcitrant lateral epicondylitis with release of the common extensor origin according to Hohmann and to determine any prognostic factors. METHODS: Eighty tennis elbows in 77 patients with a characteristic history of activity-related pain at the lateral epicondyle interfering with the activities of daily living refractory to conservative care for at least 6 months and a confirmatory physical examination were included. Clinical outcome was evaluated using the QuickDASH score system. Data were collected before the operation and at the medians of 18 months (range 6-36 months; short term) and 4 years (range 3-6 years; medium term) postoperatively. RESULTS: The mean QuickDASH was improved both at the short- and the medium-term follow-ups and did not change significantly between the follow-ups. At the final follow-up, the QuickDASH was improved in 78 out of 80 elbows and 81% was rated as excellent or good (QuickDASH <40 points). We found a weak correlation between residual symptoms (a high QuickDASH score) at the final follow-up and high level of baseline symptoms (r = 0.388), acute occurrence of symptoms (r = 0.362), long duration of symptoms (r = 0.276), female gender (r = 0.269) and young age (r = 0.203), whereas occurrence in dominant arm, a work-related cause or strenuous work did not correlate significantly with the outcome. CONCLUSION: Open lateral extensor release performed as outpatient surgery results in improved clinical outcome at both short- and medium-term follow-ups with few complications. High baseline disability, sudden occurrence of symptoms, long duration of symptoms, female gender and young age were found to be weak predictors of poor outcome. LEVEL OF EVIDENCE: Case series, Level IV.

Abstract:

Abstract: We evaluated short- and medium-term results of the treatment of articular cartilage defects of the knee with autogenous cylindrical osteochondral grafts (mosaicplasty) in 69 patients (median age 33 years) with symptomatic articular cartilage defects. Data of Lysholm score and visual analogue scale (VAS) of pain (0=no pain; 100=worst possible pain) were collected before the surgery, at 12 months postoperatively and 5 to 9 (median 7) years after the surgery. At the last follow-up the patients were also asked to state their degree of satisfaction with the outcome on a VAS (0=not at all satisfied; 100=completely satisfied), and to answer if they would have undergone the surgery again if necessary (yes or no). The mean Lysholm score and VAS of pain improved from 48 and 62, respectively, at the time of surgery to 81 and 24, respectively, at the 12-months follow-up (p<0.001 for both comparisons). From 12 months postoperatively, the Lysholm score and VAS of pain deteriorated to 68 and 32, respectively at the 5- to 9-year follow-up (p<0.001 and p=0.018, respectively). The mean degree of satisfaction with the outcome was 70 (SD 28), and 61 patients (88%) stated that they would have undergone the surgery again. In conclusion, the mosaicplasty leads to improvement of symptoms and function at short- and medium-term follow-up. A deterioration of the results is observed from 12 months postoperatively to 5-9 years postoperatively.

Abstract: We compared the results of microfracture in single versus multiple symptomatic articular cartilage defects in the knee in 110 patients with a median age of 38 years (range 15-60). Cases of reoperation of the cartilage defect were classified as failures. Clinical outcome in non-failures was evaluated by the Lysholm score and grading of knee pain and function of the knee by the use of patient-administered visual analog scales (VAS; 0-100). Data were prospectively collected before the operation and at the 2- to 9-year follow-up. The single lesion or the largest of multiple lesions were located on the medial femoral condyle (n = 62), trochlea (n = 18), lateral tibia (n = 11), patella (n = 10) or lateral femoral condyle (n = 9). We treated one (n = 76), two (n = 27) or three (n = 7) lesions with a median total area of 4 cm(2) (range 1-15). A total of 24 failures (22%) were registered-18% in the single-defect subgroup and 29% in the multiple-defects subgroup. In the remaining group of patients (n = 86), the mean Lysholm score, mean pain-score (0 = no pain; 100 = worst possible pain) and mean function-score (0 = useless; 100 = full function) improved from 51, 52 and 41, respectively, to 71 (P < 0.001), 30 (P < 0.001) and 69 (P < 0.001) at the follow-up. The pain-score was significant lower (P = 0.042), and the function-score significantly higher (P = 0.001) in the group of patients with a single lesion compared to the group with 2 or 3 lesions. The Lysholm score did not differ significantly between the two subgroups (P = 0.06).

Abstract: BACKGROUND: Frozen shoulder is a debilitating, long-lasting condition. At Bergen Surgical Hospital we have performed arthroscopic capsular release since 2003 in patients where conservative treatment has failed. The procedure is done as day surgery. The purpose of this study was to evaluate our results. PATIENTS AND METHODS: From June 2003 until October 2005 arthroscopic capsular and ligament release was performed in 66 patients (70 shoulders) with primary frozen shoulder. Oxford shoulder score and range of motion were recorded prospectively. Follow-up was done during autumn 2005 and included subjective evaluation of symptoms, function, satisfaction with the result of the procedure, Oxford shoulder score and clinical examination. RESULTS: 62 out of 66 patients would agree to have the same procedure done again. Degree of satisfaction with the result of the procedure (0 = worst, 10 = best) was 8.6 +/- 1.8 (SD) on average. Ability to work, physical activity and quality of night's sleep improved significantly (p < 0.001). Oxford shoulder score (12 = best, 60 = worst) decreased significantly from 41.0 +/- 7.5 (SD) to 18.4 +/- 7.3 (SD) (p < 0.001). External rotation, abduction and flexion increased significantly (p < 0.001). INTERPRETATION: The results from treatment of frozen shoulder with arthroscopic capsular release are good and suggest that the the condition shoulder is shortened. The procedure may be done safely as day surgery. We feel that more patients may benefit from the procedure.

Abstract: BACKGROUND: The optimal treatment for cartilage lesions has not yet been established. The objective of this randomized trial was to compare autologous chondrocyte implantation with microfracture. This paper represents an update, with presentation of the clinical results at five years. METHODS: Eighty patients who had a single chronic symptomatic cartilage defect on the femoral condyle in a stable knee without general osteoarthritis were included in the study. Forty patients were treated with autologous chondrocyte implantation, and forty were treated with microfracture. We used the International Cartilage Repair Society, Lysholm, Short Form-36, and Tegner forms to collect clinical data, and radiographs were evaluated with use of the Kellgren and Lawrence grading system. RESULTS: At two and five years, both groups had significant clinical improvement compared with the preoperative status. At the five-year follow-up interval, there were nine failures (23%) in both groups compared with two failures of the autologous chondrocyte implantation and one failure of the microfracture treatment at two years. Younger patients did better in both groups. We did not find a correlation between histological quality and clinical outcome. However, none of the patients with the best-quality cartilage (predominantly hyaline) at the two-year mark had a later failure. One-third of the patients in both groups had radiographic evidence of early osteoarthritis at five years. CONCLUSIONS: Both methods provided satisfactory results in 77% of the patients at five years. There was no significant difference in the clinical and radiographic results between the two treatment groups and no correlation between the histological findings and the clinical outcome. One-third of the patients had early radiographic signs of osteoarthritis five years after the surgery. Further long-term follow-up is needed to determine if one method is better than the other and to study the progression of osteoarthritis.

Abstract: BACKGROUND: Frozen shoulder is a debilitating, long-lasting condition. At Bergen Surgical Hospital we have performed arthroscopic capsular release since 2003 in patients where conservative treatment has failed. The procedure is done as day surgery. The purpose of this study was to evaluate our results. PATIENTS AND METHODS: From June 2003 until October 2005 arthroscopic capsular and ligament release was performed in 66 patients (70 shoulders) with primary frozen shoulder. Oxford shoulder score and range of motion were recorded prospectively. Follow-up was done during autumn 2005 and included subjective evaluation of symptoms, function, satisfaction with the result of the procedure, Oxford shoulder score and clinical examination. RESULTS: 62 out of 66 patients would agree to have the same procedure done again. Degree of satisfaction with the result of the procedure (0 = worst, 10 = best) was 8.6 +/- 1.8 (SD) on average. Ability to work, physical activity and quality of night's sleep improved significantly (p < 0.001). Oxford shoulder score (12 = best, 60 = worst) decreased significantly from 41.0 +/- 7.5 (SD) to 18.4 +/- 7.3 (SD) (p < 0.001). External rotation, abduction and flexion increased significantly (p < 0.001). INTERPRETATION: The results from treatment of frozen shoulder with arthroscopic capsular release are good and suggest that the the condition shoulder is shortened. The procedure may be done safely as day surgery. We feel that more patients may benefit from the procedure.

Abstract: BACKGROUND: New methods have been used, with promising results, to treat full-thickness cartilage defects. The objective of the present study was to compare autologous chondrocyte implantation with microfracture in a randomized trial. We are not aware of any previous randomized studies comparing these methods. METHODS: Eighty patients without general osteoarthritis who had a single symptomatic cartilage defect on the femoral condyle in a stable knee were treated with autologous chondrocyte implantation or microfracture (forty in each group). We used the International Cartilage Repair Society, Lysholm, Short Form-36 (SF-36), and Tegner forms to collect data. An independent observer performed a follow-up examination at twelve and twenty-four months. Two years postoperatively, arthroscopy with biopsy for histological evaluation was carried out. The histological evaluation was done by a pathologist and a clinical scientist, both of whom were blinded to each patient's treatment. RESULTS: In general, there were small differences between the two treatment groups. At two years, both groups had significant clinical improvement. According to the SF-36 physical component score at two years postoperatively, the improvement in the microfracture group was significantly better than that in the autologous chondrocyte implantation group (p = 0.004). Younger and more active patients did better in both groups. There were two failures in the autologous chondrocyte implantation group and one in the microfracture group. No serious complications were reported. Biopsy specimens were obtained from 84% of the patients, and histological evaluation of repair tissues showed no significant differences between the two groups. We did not find any association between the histological quality of the tissue and the clinical outcome according to the scores on the Lysholm or SF-36 form or the visual analog scale. CONCLUSIONS: Both methods had acceptable short-term clinical results. There was no significant difference in macroscopic or histological results between the two treatment groups and no association between the histological findings and the clinical outcome at the two-year time-point. Level of Evidence: Therapeutic study, Level I-1a (randomized controlled trial [significant difference]). See Instructions to Authors for a complete description of levels of evidence.

Abstract: PURPOSE: Focal chondral or osteochondral defects can be painful and disabling, have a poor capacity for repair, and may predispose patients for osteoarthritis. New surgical procedures that aim to reestablish hyaline cartilage have been introduced and the results seem promising. The purpose of this study is to provide reliable data on chondral and osteochondral defects in patients with symptomatic knees requiring arthroscopy and to calculate the prevalence of patients who might benefit from cartilage repair surgery. TYPE OF STUDY: Prospective study. METHODS: One thousand consecutive knee arthroscopies were included in this study. Immediately after each arthroscopy, the surgeon completed a questionnaire providing detailed information about the findings. Chondral and osteochondral lesions were classified in accordance with the system recommended by the International Cartilage Repair Society (ICRS). RESULTS: Chondral or osteochondral lesions (of any type) were found in 61% of the patients. Focal chondral or osteochondral defects were found in 19% of the patients. In these patients, 61% related their current knee problem to a previous trauma, and a concomitant meniscal or anterior cruciate ligament injury was found in 42% (n = 81) and 26% (n = 50), respectively. The mean chondral or osteochondral total defect area was 2.1 cm(2) (range, 0.5 to 12; standard deviation [SD], 1.5). The main focal chondral or osteochondral defect was found on the medial femoral condyle in 58%, patella in 11%, lateral tibia in 11%, lateral femoral condyle in 9%, trochlea in 6%, and medial tibia in 5%. It has been suggested that cartilage repair surgery may be most suitable in patients younger than 40 to 50 years old. A single, well-defined ICRS grade III or IV defect with an area of at least 1 cm(2) in a patient younger than 40, 45, or 50 years accounted for 5.3%, 6.1%, and 7.1% of all arthroscopies, respectively. CONCLUSIONS: Our study supports the contention that articular cartilage defects are common. It has the advantages of a prospective design and use of a new classification system recommended by the ICRS. This modern system focuses on objectively measurable parameters of the lesion's extent and not its surface appearance.

Abstract: Revascularisation of bone grafts is influenced by both the anatomical origin and the pre-implantation processing of the graft. We investigated the revascularisation by entrapment of 141Ce (cerium)-labelled microspheres in large, fresh and demineralised syngeneic grafts of predominantly cancellous (iliac bone) or cortical (tibial diaphysis) bone three weeks after heterotopic implantation in rats. The mean (SD) 141Ce deposition index (counts per minute (cpm) of mg recovered implant/cpm of mg host iliac bone) was higher in fresh iliac bone grafts, 0.98 (0.46) compared to that of demineralised iliac bone, 0.32 (0.20), p < 0.001, and fresh tibial bone grafts, 0.51 (0.27), p = 0.007. We found no significant difference in the mean 141Ce deposition index between fresh tibial bone grafts and demineralised tibial bone grafts, 0.35 (0.42), p = 0.4, or between demineralised tibial grafts and demineralised iliac bone grafts, p = 0.8. The results suggest that whereas fresh cancellous grafts are revascularised more completely than fresh cortical grafts, there is no difference in the revascularisation of demineralised cancellous and cortical grafts. In addition, fresh cancellous bone is revascularised more completely than demineralised cancellous bone, whereas there is no difference between fresh and demineralised cortical bone.

Abstract: Bone formation generally depends on adequate blood flow. Failure of bone grafts has been attributed to delayed revascularisation of the graft. We compared the relationship between revascularisation and osteogenesis, evaluated as entrapment of (141)Ce-labelled microspheres and uptake of (85)Sr, respectively, in fresh or demineralised syngeneic bone grafts 3 weeks after heterotopic implantation in rats. Whereas a moderately high linear correlation between (85)Sr and (141)Ce radioactivity was found both in the (intact) host iliac bone (r = 0.75, p = 0.0001) and implanted fresh syngeneic grafts (r = 0.50, p = 0.001), no correlation could be demonstrated in demineralised grafts (r = 0.09, p = 0.6). The results may indicate differences in the mechanisms of vascularisation and osteogenesis in the grafts used fresh or after demineralization but are, at present, difficult to fully explain.

Abstract: Implantation of demineralized bone induces new bone formation by the action of contained growth factors, of which bone morphogenetic proteins are of prime importance. A biodegradable polymer may be used as a carrier for demineralized bone particles or recombinant bone growth factors to prevent displacement of the implant, preserve its volume and shape, and assure sustained release of the incorporated active components. A polymer for this use should be biocompatible and completely absorbed without interfering with the osteogenesis. We investigated the host-tissue response and effect on demineralized bone-induced bone formation by two biodegradable polymers, a poly(ortho ester) and an amorphous low-molecular poly(DL-lactic acid). Both polymers had a plastic consistency, could easily be molded, and adhered well to the demineralized bone particles. Demineralized bone particles were implanted alone and in combination with each of the polymers in the abdominal muscles of 45 male Wistar rats. Four weeks after the operation the implants were recovered and subjected to (85)Sr uptake analysis to quantify bone formation and histologic examination. The poly(ortho ester) provoked little inflammation; it was largely absorbed by 4 weeks, and no qualitative or quantitative effect on bone formation was found. The poly(DL-lactic acid) provoked a chronic inflammation with multinuclear giant cells, macrophages with engulfed material, and proliferating fibroblasts; part of the material was still present, and the bone formation was inhibited.

Abstract: Articular cartilage has little ability to regenerate. Cartilage lesions usually persist, may provoke pain, swelling, locking and disability, and may predispose for development of osteoarthritis. Long-term results after traditional surgical techniques are unsatisfactory. In recent years, auto-transplantation of chondrocytes and osteochondral cylinder grafts aimed at reconstituting the chondral surface has been introduced. By the mosaicplasty technique, osteochondral grafts are transplanted from areas of little weight bearing at the outer limits of the trochlea to the focal lesion in the same knee. Since March 1998, 35 consecutive mosaicplasties in 33 patients (median age 35 years) have been performed at our hospital. The median area of the lesions was 2.8 sq. cm and the lesions were located at the femoral condyles, trochlea or patella. Six to twelve months post-operatively we found significant improvement of the Lysholm kneescore, from 40 (SD 14) pre-operatively to 84 (SD 14) (p < 0.001), and on the Cincinnati kneescore (pain, swelling, giving way, catching and as total evaluation). Short-term results are good regarding symptoms and knee function. The method is some-what complicated, especially when performed arthroscopically. There are few complications. Mosaicplasty may be considered in cartilage lesions of moderate size (1 to 5 sq. cm) on the femoral condyles, trochlea and patella.

Abstract: Bone contains several growth factors, including bone morphogenetic proteins (BMPs), transforming growth factor beta (TGF-beta), insulin-like growth factors I and II (IGF-I and IGF-II), platelet derived growth factor (PDGF) and basic and acidic fibroblast growth factor (bFGF and aFGF). Spatial and temporal variations in the expression and secretion of the various growth factors have been demonstrated in osteoblastic cultures and in various experimental and clinical in vivo models, including fracture healing in humans. Local application of various growth factors influences proliferation, differentiation and protein synthesis in osteoblastic cultures and bone formation in different animal models, including experimental fractures and skeletal defects. The BMPs are the only growth factors known to provoke bone formation heterotopically by making undifferentiated mesenchymal cells differentiate into osteoblasts (osteoinduction). BMPs and other growth factors, soon to become commercially available for clinical use, need a delivery system for their sustained release, as the factors are otherwise rapidly absorbed. Some existing systems inhibit bone formation by inducing chronic inflammation or physically by unresorbed carrier obstructing bone formation. New delivery systems are being investigated.

Abstract: Chondrocytes in adult human cartilage have little mitotic capacity even after injuries. Deep injuries penetrating the subchondral bone plate lead to the release of pluripotent mesenchymal stem cells which have the potential to differentiate into different types of connective tissue, including bone and cartilage. The release and stimulation of these stem cells can also be achieved by drilling or microfracture of the subchondral bone of cartilage lesions. When stimulated, periosteal cells may also differentiate into chondrocytes. However, non-chondrocyte determined cells seem to induce mainly fibrocartilage. In 1987 autologous chondrocyte implantation was introduced by a team in Gothenburg. This resulted in clinical improvement and the development of hyaline-like cartilage in patients who had undergone treatment. We first used the method in 1996 in a clinical trial. At a 6-month follow-up of our first 12 patients we found reduced symptoms and improved knee function. This method is promising, but further clinical trials are necessary.

Abstract: Bone contains several growth factors, including bone morphogenetic proteins (BMPs), transforming growth factor beta (TGF-beta), insulin-like growth factors I and II (IGF-I and IGF-II), platelet derived growth factor (PDGF) and basic and acidic fibroblast growth factor (bFGF and aFGF). The BMPs are the only factors known to provoke bone formation heterotopically by making undifferentiated mesenchymal cells differentiate into osteoblasts (osteoinduction). Much of our knowledge of osteoinduction derives from studies in rodents of heterotopically implanted demineralised bone which contains various growth factors, including BMPs. This model has been used to examine the effect on osteoinduction of different factors, including the type of host soft tissue, age and species of donor and recipient, demineralisation procedure, storage and sterilisation procedures, experimental diabetes, dietary factors, hormones, growth factors, caffeine, biphosphonates, indomethacin and biomaterials. Demineralised bone enhances bone formation experimentally in various animal models, including cranio-maxillofacial reconstructions, healing of diaphyseal defects, and spinal fusion; demineralised bone has also been used in a limited way clinically. However, sufficient osteoinduction in humans may require a higher concentration of BMPs and other growth factors than those found in demineralised bone.

Abstract: Demineralized allogenic bone implanted in the subcutis or muscle of rodents causes formation of heterotopic bone by osteoinduction. The osteoinductive response may be weaker in primates than in rodents. It was suggested that the osteoinductive response of demineralized bone for clinical use could be enhanced by using young donors, because studies have indicated that the osteoinductive response is reduced in demineralized bone of old versus young donors. However, these findings may not represent a gradual decline in the osteoinductive property of bone matrix throughout the life span. We evaluated quantitatively, by uptake of strontium 85, the osteoinductive effect of demineralized bone matrix from newborn, 8-week-old (adolescent), and 8-month-old (adult) male Wistar rats implanted in the abdominal muscles of 8-week-old male Wistar rats. The osteoinductive response increased significantly with increasing donor age. The results of the present study, weighed with those of previous studies, indicate that the osteogenic potential of the bone matrix increases from newborn to adulthood but decreases in the aged rat. This may be due to changes in concentration of essential growth factors (e.g., bone morphogenetic proteins) resulting from maturational changes from birth to adulthood and osteoporotic changes occurring in later years. The results do not support the contention that young donors of demineralized bone are preferable to adult donors.

Abstract: We have used open reduction and internal fixation with a T-plate in 31 displaced, intraarticular fractures of the distal radius which were judged irreducible or in which closed reduction failed. The mean follow-up time was 4 (3-7) years. The dorsal angulation, the radial length, the articular step-off and the intraarticular gap between fragments were substantially improved after surgery. 30 patients had excellent or good extraarticular alignment, and only 1 patient had a postoperative intraarticular step-off of 2 mm. The function was excellent or good in 26 patients at follow-up. Complications occurred in 6 patients: 1 compartment syndrome, 1 postoperative wound infection, 2 ruptures of the extensor pollicis longus tendon, and 2 patients had median nerve paresthesias.

Abstract: All cruciate ligament injuries in the three upper divisions for men and women (3392 players) in Norwegian team handball in the 1989-90 and 1990-91 seasons were registered. A questionnaire was mailed to all injured players. Ninety-three cruciate ligament injuries were registered; 87 in the anterior cruciate ligament (ACL), and six in the posterior cruciate ligament (PCL). Among women, 1.8% were injured compared with 1.0% of the men. In the first division, the risk of being injured was considerably higher: 4.5% of the players had a cruciate ligament injury. There were 0.97 cruciate ligament injuries per 100 playing hours in the three divisions taken together. Seventy-five per cent of the injuries occurred during games. Ninety-five per cent involved no contact between players. Activities in which the friction between shoe and floor was significant caused 55% of the injuries. Injuries caused by running into another player contributed to only 5% of the injuries. No significant differences were observed in injury incidence during matches between different types of floors (parquet, Pulastic and other synthetic surfaces.)

Abstract: The anatomical and functional outcome and complications after closed reduction and external fixation of unstable fractures of the distal radius were reviewed in 29 patients. The fractures were reduced by longitudinal traction and closed manipulation under fluoroscopic control, and the reduced position was retained by a standard half-frame Hoffmann external fixator for six to eight weeks. The mean follow-up time was four (3-7) years. The reduction failed in three patients after too early removal of the fixator (three to five weeks). For the rest of the patients the dorsal angulation, the radial length, the articular step-off, and the intra-articular gap between fragments were significantly improved. Twenty-two patients had excellent or good anatomical alignment and in seven it was fair. One patient had a superficial pin infection, six patients had transient paraesthesias, and one patient transient mild dystrophia. At follow-up one patient had some finger stiffness; this was the only persistent complication. The median Gartland and Werley functional score was 3. The functional end result was excellent or good in 22 patients, fair in four, and poor in three.

Abstract: BACKGROUND AND AIMS: Our knowledge on how often tears of the anterior cruciate ligament (ACL) initially remain undetected and the outcome of the resulting non-operative regimen is still incomplete. To investigate these issues, we conducted a follow-up study in young individuals that 4 to 5 years earlier had sustained a knee injury during a sports event that had been diagnosed as a first-degree sprain. MATERIAL AND METHODS: The patients (n = 54) were grouped according to present symptoms (pain or instability): A, no symptoms (n = 27), B, moderate symptoms (n = 16) and C, severe symptoms (n = 11). Eight group A patients, 11 group B patients and 8 group C patients participated in the follow-up study. Symptoms and level of activity were evaluated and clinical examination of the knee and KT-1000 instrumented measurement of anterior knee laxity were performed. RESULTS AND CONCLUSIONS: Increased anterior laxity was demonstrated in 7 patients (1 in group B and 6 in group C). In the same period these injuries occurred, acute ACL rupture was diagnosed in our region in 16 patients. The proportion of overlooked ACL ruptures to injuries interpreted as a first-degree sprain and to total number of ACL ruptures sustained during the same period was at least 7 out of 54 (13%) and at least 7 out of 23 (30%), respectively. The subjective symptom score was higher and Lysholm's and Tegner's scores lower in the patients with increased anterior laxity compared to the patients with no increased anterior laxity. We conclude that ACL rupture may be overlooked in a rather high proportion and that the 4-5 years' result in such injuries is poorer than in those without increased anterior laxity.

Abstract: Fifty open tibial fractures were treated with the Ex-fi-re external fixation system from 1987 to 1994. According to the Gustilo and Anderson classification, there were 12 Grade I, 14 Grade II, 10 Grade IIIA, 13 Grade IIIB, and 1 Grade IIIC injuries. Eight fractures were segmental. The average patient patient age was 39 years (range, 16-85 years). With the reduction unit of the system, displaced tibial fractures could be reduced by the functions of the device in contrast to the manual reductions needed with other unilateral devices. Compression could be applied even to oblique fractures. The reductions were performed by this unit in all cases and were classified as exact in 28 of 41 cases. Exact reduction was defined as a reduction in which there was no more than 2 mm of translational displacement. The 8 segmental fractures were not classified according to reduction. Forty-three fractures healed with no secondary procedure. Three secondary bone graftings, 4 fibulotomies, and 3 renamed intramedullary fixations were performed in 6 patients. Thirty-two skin grafts were performed. There was 1 fracture site infection, and 1 curettage and 1 sequestrectomy were performed after union. At 1 year followup there were no signs of infection. Median time to union was 20 weeks, and median time to full unprotected weightbearing was 22 weeks. Fractures with an exact reduction had a median time of union of 19 weeks, compared with a median of 31 weeks in reductions with greater than 2 mm translational displacement. The exact reduction and translational compression applied in oblique fractures appeared to contribute to early consolidation.

Abstract: Thirty 8-week-old male Wistar rats were randomly allocated into three groups of 10 rats each. A 5-mm defect in the left parietal bone was made in each rat. In the defects of the first group of rats, no implant was used (control group). In the second group, polyorthoester membranes were placed in the defects without active substance. In the third group, polyorthoester membranes were placed with insulinlike growth factor I. The rats were sacrificed 6 weeks postoperatively. Bone formation in the defects was quantified by computer-assisted measurements of the area of the residual defect on radiographs. Host-tissue response was evaluated by light microscopy. The area of residual bone defect was greatest in the control group, less for the defects with polyorthoester membrane without active substance, and least for the defects with polyorthoester membranes with the growth factor. During histologic evaluation, no inflammation was seen, and only traces of the polyorthoester were detected in the defects with polyorthoester membrane with or without the growth factor.

Abstract: During 1988 we recorded all Colles' fractures (n = 530) in a prospective study in the city of Bergen. According to defined criteria, the fractures were treated by immobilisation in plaster cast with or without reduction; reduction and immobilisation by a Hoffman external fixation device; or open reduction and internal fixation. Included in the present study were 26 patients with secondary displacement after immobilisation in a plaster cast (8% of the reduced fractures). The fractures were remanipulated and splinted in a new cast for four more weeks. The patients were followed up five years after the fracture, and underwent subjective, radiographic, and functional evaluation. The anatomical end result was significantly improved compared with the initial deformity. The dorsal angulation improved significantly compared with the "slipped' position, whereas the radial length did not. The functional end result was excellent or good in 20 patients (77%). The total movement in all directions was correlated negatively with ulna plus, and the grip strength correlated negatively with the degree of osteoarthrosis. There were no other significant linear relationships between anatomical and functional variables. Total pronation and supination correlated with the initial radial length and dorsal angulation, and the total movement in all directions correlated with the initial radial length.

Abstract: Inhibition of orthotopic reossification after surgical removal of bone is sometimes indicated and may be accomplished by implantation of interpositional materials or by systemic administration of indomethacin. However, implantation of nonresorbable foreign material may induce a chronic inflammation and predispose to infections; and systemic administration of indomethacin may induce systemic adverse effects. We studied the effect of local delivery of indomethacin by a bioerodible polyorthoester on the reossification of segmental defects of the radius in rats. We divided 45 Wistar rats into three groups, A-C. A 3.5 mm-long middiaphyseal osteoperiosteal resection of the right radius was made in each rat. The defect was filled with 15 mg of polyorthoester with 5% indomethacin in group A and 15 mg of polyorthoester without drug in group B. No material was implanted in the defects in the group C rats. The rats were killed 50 days postoperatively. The mean area of the residual defects were greater in the defects with the polyorthoester with 5% indomethacin compared with defects with polyorthoester without drug or without implant as judged by computer-assisted area measurements on radiographs. By light microscopy, no inflammation was seen and only traces of the polyorthoester could be detected in the defects filled with the polyorthoester with or without indomethacin. The results of this study suggest that the polyorthoester may be used as a bioerodible system for local delivery of indomethacin to inhibit reossification of skeletal defects without tissue reaction, unabsorbed carrier, or systemic effects.

Abstract: It has been shown that different sterilization procedures of demineralized bone may influence its osteoinductive properties. The aim of this study was to evaluate the effect of ethylene oxide sterilization for 1, 3, and 6 hours on the osteoinductive potential of allogeneic demineralized bone implanted heterotopically in rats. Sixty male Wistar rats were randomly assigned to one of four groups, A through D, and four demineralized bone chips (2.8 mg) were implanted in a pouch created between the right oblique abdominal muscles in each animal. In Group A, the demineralized bone was implanted without prior sterilization of the material, whereas the demineralized bone implanted in Groups B, C, and D had been sterilized in ethylene oxide gas for 1, 3, or 6 hours, respectively, and aerated for 48 hours. At 4 weeks postoperatively, bone formation was evaluated quantitatively by strontium 85 uptake and qualitatively by light microscopy of histological sections. One-way analyses of variance at the 0.05 level revealed no significant difference in strontium 85 uptake of the different groups, and no qualitative differences in osteoinduction could be detected by light microscopy. Ossicles consisting of bone and bone marrow were seen in the recovered implants of all groups.

Abstract: Several studies have suggested that grafts from membranous derived bone (e.g., calvarial grafts) retain their volume better than those from endochondral derived bone (e.g., iliac bone grafts). Increased osteogenesis in grafts of the former type has been offered as the explanation. However, simple volume measurements of the recovered grafts do not differentiate between viable and dead bone. We studied fresh syngeneic full-thickness bone grafts from calvaria, mandibula, tibia diaphysis, and iliac bone implanted in the back muscles of young Lewis rats. Bone formation in grafts recovered 3 weeks postoperatively was quantitatively evaluated by strontium 85 uptake analyses. We found that the strontium 85 uptake was greater in calvarial and mandibular grafts than in tibial grafts. No difference was found among calvarial, mandibular, and iliac grafts or between tibial and iliac grafts. We conclude that the anatomical area of harvest is important regarding new bone formation in syngeneic bone grafts. However, the results do not support the contention that better maintenance of volume of calvarial grafts compared with iliac bone grafts is due to enhanced osteogenesis in the former.

Abstract: Forty-two patients referred to the outpatient clinic of Hagavik Orthopaedic Hospital within 3 weeks after an acute knee injury was found by arthroscopy to have a partial or total tear of the anterior cruciate ligament (ACL). In these patients, the results of clinical tests and instrumented laxity tests without anesthesia prior to the arthroscopy were analyzed. The Lachman test and the maximum anterior pull (150-200 N) KT-1000 instrumented test revealed abnormal laxity in 33 and 37 of 42 cases, respectively. Both tests revealed abnormal laxity more often than the KT-1000 test using 67 N (10/42) and the maximum anterior pull KT-1000 instrumented test also revealed abnormal laxity more often than the KT-1000 test using 89 N (25/42). By logistic regression analysis, the maximum anterior pull KT-1000 instrumented test was associated with rupture of the ACL (partial or total rupture). The results show that adequate anterior pull has to be used to overcome muscle tension to reveal abnormal laxity in acute ACL tears using the KT-1000 arthrometer.

Abstract: A requirement for the clinical use of demineralized bone is the possibility of storing the material without loss of its osteoinductive properties. Seventy-five 8-week-old male Wistar rats were randomly assigned to one of five groups of 15 rats each. Lyophilized demineralized allogeneic bone was prepared and implanted in the abdominal muscle either without prior storage (control group) or after storage for 9 or 14 months at -70 degrees C or 4 degrees C (four experimental groups). Bone formation in the implants was evaluated quantitatively 4 weeks postoperatively by measuring the strontium 85 uptake of the recovered implants. Storage for 9 months at both temperatures did not affect the osteoinduction, whereas storage for 14 months at both temperatures led to a statistically significant decrease in osteoinduction.

Abstract: Some studies have suggested that membranous bone grafts undergo less resorption than endochondral grafts, and faster revascularization of the former has been proposed as the explanation. We studied fresh syngeneic full-thickness bone grafts from calvaria, mandibula, tibia diaphysis, and iliac bone implanted in the back muscles of young Lewis rats. As a measure of the quantity of cancellous bone in grafts before implantation, the ratio of the total area of soft-tissue spaces to the total area of the graft was measured histomorphometrically. Revascularization in grafts 3 weeks postoperatively was evaluated by deposit of 141Ce-labeled microspheres. Both the quantity of cancellous bone (before implantation) and the revascularization (3 weeks postoperatively) were greater in the mandibular and iliac bone grafts than in the calvarial and tibia diaphyseal grafts. The results suggest that the anatomical area of harvest of bone graft is important regarding early revascularization, but the results do not support the theory that different embryological mode of development is the cause since mandibula (high 141Ce index) and calvaria (low 141Ce index) are of membranous origin and iliac bone (high 141Ce index) and tibia (low 141Ce index) are of endochondral origin. The difference in revascularization between the different grafts may be explained by differences in quantity of cancellous bone since cancellous bone is revascularized faster than cortical bone.

Abstract: In a prospective study, 645 consecutive Colles' fractures treated conservatively were followed until union. The fractures subsequently lost some of their manipulated position during the immobilization period. However, the anatomical end result was significantly improved compared with the initial deformity. The mean shortening of the radius during plaster-cast treatment was 3 mm, and the mean increase of dorsal angulation was 7 degrees. Multiple regression analyses showed that initial dorsal angulation, age, and Older type were important predictor variables for the end result of dorsal angulation. Initial radial length, age and initial dorsal angulation were of importance for the end result of radial length. The strongest linear relationship was found between the end result of radial length and the initial radial length (r = 0.67). This may indicate that the patients who will malunite with radial shortening are those with significant radial axial shortening at the initial presentation. Thus, these patients should be treated with a more stable fixation device.

Abstract: Anterior cruciate ligament reconstruction by free patellar tendon graft was performed using 2 different surgical approaches to the intercondylar notch in 67 consecutive patients with chronic anterior cruciate ligament insufficiency. In the first 30 patients (Group A), the traditional medial parapatellar arthrotomy with lateral luxation of the patella was done, whereas in the last 37 patients (Group B) a transpatellar tendon approach was used. Postoperative pain was managed by analgesics and, in patients who had epidural anesthesia, by administration of bupivacaine in indwelling catheters. Generally, the analgesics and bupivacaine were given immediately on request to establish comfort at rest and to permit range of motion exercises without severe pain. Compared with those in Group A, the patients of Group B had a significantly longer period from the first dose of analgesic or bupivacaine to the second, and the total number of doses of analgesic or bupivacaine was significantly lower. In the subgroup of patients with epidural anesthesia (21 in Group A and 32 in Group B), the Group B patients required significantly less analgesics, as doses equivalent to 10 mg of morphine, compared with that of Group A.

Abstract: Three different membranes were tested for guided bone regeneration in 8-mm unicortical trephine defects in rabbit tibia. All experimental and control defects healed with bone. The critical size defect in rabbit tibia is larger than 8 mm, because control defects, 8 mm in diameter, healed spontaneously. Around remnants of the biodegradable Polyglactin 910 mesh (Vicryl@), a diffuse infiltration of inflammatory cells with multinuclear giant cells developed. However, the bone healing was not impaired by the infiltrate. Around the Gore-Tex@ membrane and around remnants of the Alzamer] a few lymphocytes were observed, but no multinuclear giant cells were noted.

Abstract: The effect of a composite of demineralized bone mixed with polyorthoester on the healing of large segmental defects in the rat radius was studied. Sixty male Wistar rats were divided into four groups, A through D, and an osteoperiosteal diaphyseal defect of 50 per cent of the length of the bone was made in the right radius of each rat. In Group A, the defect was filled with polyorthoester and demineralized bone; in Group B, demineralized bone; and in Group C, polyorthoester. No material was implanted in the defects in the Group-D rats. The rats were killed fifty days postoperatively. The formation of bone in the defects was quantified with computer-assisted measurements of the area on radiographs. The host-tissue response was evaluated with light microscopy. Defects that had been filled with the composite of polyorthoester and demineralized bone or with demineralized bone alone showed regeneration of bone corresponding to 93.6 and 77.6 per cent of the area of the defect, respectively. Defects that had no implant or that had been filled with polyorthoester alone showed significantly less formation of bone. No inflammation was seen with light microscopy, and only traces of the polyorthoester could be detected in the defects that had been filled with the composite or with polyorthoester alone.

Abstract: Host tissue response and heterotopic osteoinduction by composites of demineralized bone matrix and three different substances used as bioresorbable carriers implanted in the abdominal muscles were evaluated by strontium 85 uptake and histology 4 weeks postoperatively in 60 male Wistar rats. Both fibrin-collagen paste and fibrin sealant inhibited bone induction and produced a chronic inflammation; part of the fibrin-collagen paste was still present at 4 weeks. Polyorthoester with gentamicin was almost completely absorbed, induced minimal tissue reaction, and did not inhibit osteoinduction.

Abstract: Local hemostatics for osseous tissue should preferably be absorbable and biocompatible and should not inhibit osteogenesis. The tissue response and effect on demineralized bone-induced heterotopic osteogenesis in the abdominal muscle of 120 male Wistar rats by different local hemostatics were evaluated by light microscopy and 85Sr uptake analyses. Non-absorbable bone wax of 88% beeswax and absorbable bovine fibrin-collagen paste both significantly inhibited osteoinduction, whereas a bioerodible polyorthoester drug delivery system with or without 4% gentamicin did not. Bone wax was not absorbed and induced a chronic foreign body reaction. Fibrin-collagen paste induced less inflammation with numerous monocytes and macrophages with engulfed material. Bioerodible polyorthoester caused a very moderate tissue reaction and was mostly resorbed at week 4.

Abstract: A study was performed to evaluate regeneration of defects in rat calvaria either unfilled or filled with a bioerodible polyorthoester only, demineralized bone only, or a composite of both. At 4 weeks, histological and radiographic studies showed that defects filled with a composite of bioerodible polyorthoester and demineralized bone or demineralized bone alone were bridged by bone. Unfilled defects or defects filled with polyorthoester only did not heal. The polyorthoester caused slight inflammation that subsided by 3 weeks, and only traces of the filler could be detected at 4 weeks. The polyorthoester provided local hemostasis when used either alone or in composites with demineralized bone. The composite implant was moldable, easily contoured, and technically easier to use than demineralized bone alone.

Abstract: Heterotopic bone formation in the abdominal muscle of 45 male 8-week-old Wistar rats induced by implantation of 5, 10, or 15 mg demineralized bone (DBM) powder was evaluated at 4 weeks by 85Sr uptake of the implants and area histomorphometry of the induced bone. Two indices of 85Sr uptake were calculated: the osteogenic index [(counts/min/mg implant)/(counts/min/mg os ilium)] and an index that we have called the osteoquantum index in which the weight of the implant is disregarded [(counts/min implant)/(counts/min/mg os ilium)]. The osteoquantum index showed a linear relationship to the area of the induced bone with a correlation coefficient (r) of 0.90. Only weak linear relationships were found between the osteogenic index and the area of the bone (r = 0.32) and between the osteogenic index and the osteoquantum index (r = 0.33). The osteoquantum index and the area of the induced bone both increased with increasing mass of implanted DBM, whereas the osteogenic index did not change.

Abstract: A study was done to evaluate the effect of a system for the local delivery of indomethacin on demineralized bone-induced formation of heterotopic bone in the abdominal muscles of rats. Two separate investigations were conducted on a total of forty-eight Wistar rats. In both series, two types of implants were used: polyorthoester and demineralized bone (Group A, the control group) and polyorthoester with 5 per cent indomethacin and demineralized bone (Group B, the experimental group). In the first series, host-tissue responses and osteoinduction were evaluated histologically at two, three, and four weeks after the implantation. In the second series, the formation of bone was quantified on the basis of uptake of 85Sr at four weeks after the implantation. The polyorthoester system for the local delivery of indomethacin significantly inhibited demineralized bone-induced heterotopic formation of bone, as demonstrated by light microscopy and by uptake of 85Sr. The polyorthoester, with or without the drug, caused little tissue reaction and was resorbed almost completely at four weeks.

Abstract: The platelets play an important role in the normal hemostasis, and it is known that both natural and synthetic macromolecules may induce platelet activation and aggregation. Thus, the purpose of the present study was to investigate the platelet aggregating effect of five different local hemostatics. Platelet aggregation was assessed by aggregometry. Unwoven fleece of bovine collagen polymer in fibrillar form induced aggregation in combination with small amounts of platelet agonists; ADP and adrenaline. Ordinary, nonabsorbable bone wax also induced aggregation in combination with the agonists, but larger concentrations of agonists were needed. Bioerodible polyorthoester with physical properties such as bone wax, oxidized cellulose and gelatin sponge did not promote platelet aggregation.

Abstract: A composite of a local, sustained, drug-release system, Alzamer bioerodible polyorthoester, and demineralized bone-matrix (DBM) particles implanted in the abdominal muscle of 89 Wistar rats induced cartilage and bone formation at the same rate as DBM when evaluated histologically and by 85Sr uptake. The composite implant was technically easier to use than DBM alone.