Therapy of aseptic nonunions with parathyroid hormone.

The absence of osseous consolidation of a fracture for 9 or more months with no potential to heal is defined as nonunion. Both for the patient and from a socioeconomic point of view, nonunions represent a major problem. Hypertrophic, vital nonunions are distinguished from atrophic avital ones. Risk factors for a delayed fracture healing are insufficient immobilisation, poor adaptation of the fracture surfaces or residual instability, interposition of soft tissue within the fracture gap, as well as circulation disturbances and infections. The incidence of nonunions after fractures of the long bones lies between 2.6 and 16% depending on the surgical technique used. In human and animal studies, a positive effect of parathyroid hormone (PTH) on fracture healing has been shown. PTH has a direct stimulatory effect on osteoblasts and osteoclasts. In addition, it appears to influence the effect of osseous growth factors. In this prospective study, 32 patients with nonunions were treated with teriparatide to investigate the effects of PTH on fracture healing. Definitive healing of the nonunions following PTH treatment could be observed in 95% of the cases.

Balloon sacroplasty as a palliative pain treatment in patients with metastasis-induced bone destruction and pathological fractures.

PURPOSE: In the case of metastatic involvement of the sacrum with destruction and consecutive pathological fracture, intense disabling pain is one of the defining factors. The feasibility, safety and pain development with cement augmentation were to be investigated. MATERIALS AND METHODS: CT-guided balloon sacroplasty was conducted in 10 patients with metastasis-induced bone destruction of the sacrum. After establishment of the entry point, a K-wire was first introduced as far as the central tumor lesion via the short, or transiliac axis. A cannula was then positioned over the wire. Under CT guidance, a balloon catheter was introduced through the cannula and inflated and deflated several times. The PMMA cement was then injected into the preformed cavity. The procedure was completed by a spiral CT control using the thin-slice technique. Pain intensity was determined using a visual analog scale (VAS) before the procedure, on the 2nd postoperative day and 6 months after the intervention. Finally, the patients were asked to state how satisfied they were. RESULTS: Balloon sacroplasty was technically feasible in all patients. The control CT scan showed central distribution of the cement in the tumor lesion. On average 6 +/- 1.78 (4 - 10) ml of PMMA cement were introduced per treated lesion. A significant (p < 0.001) reduction in pain according to the VAS occurred in all patients from 9.3 +/- 0.67 (8 - 10) pre-operatively to 2.7 +/- 1.28 (1 - 5) on the 2nd postoperative day and 2.9 +/- 0.81 (2 - 5) 6 months after the intervention. All of the patients were re-mobilized after the procedure and underwent the further therapeutic measures as planned. CONCLUSION: Balloon sacroplasty is a helpful therapeutic option in the overall palliative treatment of patients with tumor-induced destruction. It is a safe and practicable procedure that markedly reduces disabling pain.

[Interventional pain relief using balloon-kyphoplasty in patients with osteoporotic-based fatigue fractures of the os sacrum]. / Interventionelle Schmerztherapie mittels Ballon-Kyphoplastie bei Patienten mit osteoporosebedingten Insuffizienzfrakturen des Os sacrum.

PURPOSE: In older patients with reduced bone quality, fatigue fractures of the os sacrum are relatively common and are typically accompanied by strong, disabling pain. The aim of our study was to verify the feasibility and safety of sacroplasty using a balloon catheter as well as the reduction of pain. MATERIALS AND METHODS: 25 patients were diagnosed with an os sacrum fracture in MRI. As a manifestation of an extant bone reconstruction process, all patients were diagnosed with distinctive edema on the basis of MRI strong T 2-weighted images. CT-controlled balloon sacroplasty was performed in all patients. To allow the cement to be dispensed at a longitudinal angle to the fracture, the balloon catheter is directed through a hollow needle in the os sacrum either from the caudal to the cranial direction or from the craniodorsal to the caudoventral direction. The thus created cavity was then filled with PMMA cement. A control CT and a conventional X-ray in two planes were then carried out. The pain intensity was defined by means of VAS before the intervention, on the second day, and 6 and 12 months after the intervention. RESULTS: The balloon sacroplasty yielded good technical performance in every patient. The control CT and the X-ray control of the os sacrum showed adequate distribution of the cement, and cement leakage was not detected. Before the operation, the average pain encountered was in accordance with VAS 8.3. On the second postoperative day, a considerable reduction with an average of 2.7 was reported, and this remained stable with an average of 2.5 after 6 and 12 months. CONCLUSION: Balloon sacroplasty is an effective treatment method for fast pain relief in patients with fatigue fractures of the os sacrum.

[Ambulatory CT-assisted thoracic sympathetic block as an additional approach to treatment of complex regional pain syndromes after sport injuries]. / Ambulante CT-gestützte thorakale Sympathikusblockade als zusätzliche Therapieoption bei komplexem regionalen Schmerzsyndrom Typ I nach Sportverletzungen.

AIM: Also after bagatelle trauma, some patients can develop a complex regional pain syndrome (CRPS). The limb concerned usually shows a marked temperature difference to the contralateral side. Apart from a doughy swelling, the patient is impaired in particular by burning pain and a restricted range of motion. The objective of the present study was to examine the influence of early thoracic sympathetic nerve blockade on the basis of clinical and quantified blood flow parameters. METHODS: In 7 young patients (average age 17.7 [15 - 21] years) with a clinically developing type 1 CRPS after sport injuries (mountain bike, bike, skateboard, hockey and go-kart accidents), occult injury and ligament lesions were ruled out using conventional imaging and MRI. In addition to pain-adapted physiotherapy and pharmacotherapy with analgesics and calcitonin, sympathetic nerve blockade was performed three times at two-day intervals. The CT-assisted puncture was performed in the prone position at the level of the intervertebral space of the 2nd/3 rd thoracic vertebral bodies. In the correct paravertebral position, a 10-cm long, 22 G Seibel-Grönemeier needle was used for the successive injection of 6 - 10 ml Carbostesin 0.5 %. By adding a small amount of contrast medium, it was possible to visualise clearly the distribution of the sympathicolytic agent in the control scan in each case. Before and after the intervention, colour-coded duplex sonography (CCDS) of the affected limb arteries was performed on all patients. RESULTS: The injection needle was correctly placed in all patients, without complications. The medication mixture was observed to have distributed properly. After the intervention, all patients reported the immediate onset of marked pain relief, whereby they recovered fully over the further course. The increase in peripheral blood flow was shown by a significant improvement in flow in the CCDS. CONCLUSION: Outpatient CT-assisted temporary sympathetic nerve blockade is an effective and low-complication therapeutic option for the supportive treatment of patients with CRPS.

[Ambulatory CT-assisted thoracic sympathetic block as an additional approach to treatment of complex regional pain syndromes after sport injuries]. / Ambulante CT-gestützte thorakale Sympathikusblockade als zusätzliche Therapieoption bei komplexem regionalen Schmerzsyndrom Typ I nach Sportverletzungen.

AIM: Also after bagatelle trauma, some patients can develop a complex regional pain syndrome (CRPS). The limb concerned usually shows a marked temperature difference to the contralateral side. Apart from a doughy swelling, the patient is impaired in particular by burning pain and a restricted range of motion. The objective of the present study was to examine the influence of early thoracic sympathetic nerve blockade on the basis of clinical and quantified blood flow parameters. METHODS: In 7 young patients (average age 17.7 [15-21] years) with a clinically developing type 1 CRPS after sport injuries (mountain bike, bike, skateboard, hockey and go-kart accidents), occult injury and ligament lesions were ruled out using conventional imaging and MRI. In addition to pain-adapted physiotherapy and pharmacotherapy with analgesics and calcitonin, sympathetic nerve blockade was performed three times at two-day intervals. The CT-assisted puncture was performed in the prone position at the level of the intervertebral space of the 2nd/3rd thoracic vertebral bodies. In the correct paravertebral position, a 10-cm long, 22 G Seibel-Grönemeier needle was used for the successive injection of 6-10 ml Carbostesin 0.5 %. By adding a small amount of contrast medium, it was possible to visualise clearly the distribution of the sympathicolytic agent in the control scan in each case. Before and after the intervention, colour-coded duplex sonography (CCDS) of the affected limb arteries was performed on all patients. RESULTS: The injection needle was correctly placed in all patients, without complications. The medication mixture was observed to have distributed properly. After the intervention, all patients reported the immediate onset of marked pain relief, whereby they recovered fully over the further course. The increase in peripheral blood flow was shown by a significant improvement in flow in the CCDS. CONCLUSION: Outpatient CT-assisted temporary sympathetic nerve blockade is an effective and low-complication therapeutic option for the supportive treatment of patients with CRPS.

[Current treatment of hamate hook fractures]. / Aktuelle Behandlung der Hamulus ossis hamati-Fraktur.

PURPOSE: Hamate hook fractures can be treated conservatively or surgically, whereby fragment and fracture position, age of the fracture, associated injuries, and individual needs of the patient all influence the choice of the therapeutic procedure. Acute non-displaced fractures are frequently treated conservatively, while displaced fractures and nonunions undergo surgical treatment. We report our experience in diagnostic and therapeutic management of 14 hamate hook fractures. CLINICAL MATERIAL AND METHOD: During a three-year period, 14 patients (eleven men and three women) 21 to 73 years old (42.0 +/- 17.9 years) with fractures at the base of the hamate hook were treated at three hand surgery units. The retrospective study of all patients included a chart review, postoperative radiological imaging after one year, and clinical examinations with grip strength measurements after 18 to 34 months (27.8 +/- 4.9 months). In six patients (43 %), the acute fracture was immobilized in a lower arm cast for six weeks, while eight patients (57 %) were operated primarily. In five cases (36 %) excision of the fragment and in three cases (21 %) open reduction and internal fixation using a screw were performed. Of six patients treated conservatively, five developed nonunion after two to five months (3.0 +/- 1.2 months) with persistent pain and underwent secondary surgery. One patient was asymptomatic despite a nonunion and declined surgical treatment. In three cases the fragment was excised, while two patients underwent open reduction and internal fixation with a screw. RESULTS: All patients operated primarily were free of complaints three months after surgery. The success rate of surgical treatment (8/8) was therefore significantly higher than that after conservative treatment (1/6). CONCLUSION: Compared to conservative treatment of acute non-displaced hamate hook fractures, which is associated with a high risk of developing symptomatic nonunion, primary surgical treatment reliably yields a good clinical outcome. Here, results after fragment excision and open reduction and internal fixation are comparable.

[Simultaneous bilateral total knee arthroplasty in patients with rheumatoid arthritis]. / Einzeitiger bilateraler Kniegelenkersatz bei Patienten mit Rheumatoider Arthritis.

AIM: In the event of destruction of both knee joints, is bilateral total arthroplasty a reliable operation that the patient can reasonably be expected to undergo? METHOD: In 140 patients [35 men, 105 women, average age 48.6 (range 24-78) years], a bilateral sequential TEP implantation was performed under one anaesthesia session, due to verified destruction of both knee joints (Larsen stage III-IV). All patients were treated with a cemented surface replacement prosthesis with resurfacing of the patella (Duracon Total Knee System, Stryker/Howmedica). Functional assessment was done with the aid of the Lysholm score preoperatively as well as 6, 12 and 18 months postoperatively. RESULTS: The operation was conducted under one anaesthesia session in all patients. The average Lysholm scores improved from 26 (19-45) preoperatively, to 72 (49-81) 6 months postoperatively, 76 (48-85) 12 months postoperatively and 77 (49-87) 18 months postoperatively, whereby no significant difference between sides was observed. 96% of the patients said that they would undergo the operation again. The following complications occurred: 6 prosthesis infections (2.1%), 2 aseptic loosenings (0.7%), 8 superficial wound healing disorders (2.9%) and 2 deep vein thromboses (0.7%). CONCLUSION: Sequential bilateral total knee arthroplasty under one anaesthesia session in patients with rheumatoid arthritis facilitates a much quicker rehabilitation, while the overall perioperative risk is not increased.

[Imaging and therapy of hamulus-ossis-hamati fracture]. / Bildgebung und Therapie einer Hamulus-ossis-hamati-Fraktur.

The relatively rare fractures of the hamate bone are the most common osseous injuries of the distal carpal row, whereby fractures of both the body and the hook of the hamate occur. We present a hamulus ossis hamate fracture that was caused by direct trauma in a high-level game of underwater rugby. Although this was diagnosed by conventional x-ray, the precise position of the fracture was clearly imaged using thin-layer CT, while additional multiplanar MRT revealed further sequelae of the trauma. A CT follow-up after 10 weeks of conservative therapy did not show any osseous consolidation, which indicated the need for surgical revision with extirpation of the hamulus.

CT determination of bone mineral density and structural investigations on the axial skeleton for estimating the osteoporosis-related fracture risk by means of a risk score.

In addition to the pure measurement of bone mineral density (BMD) in osteodensitometry, the investigation of bone structure is becoming increasingly important for estimating fracture risk. In a clinical study, a risk score was proposed which separately assesses BMD and structural parameters for spongious and cortical bone and aggregates them into a single diagnostic parameter. In 120 lumbar vertebrae from 40 patients, BMD was determined separately for spongious and cortical bone by means of quantitative CT using a single energy procedure (SE-QCT/85 kV). In addition, structural parameters based on high resolution CT were calculated for the spongiosa and cortical bone. For all patients the number of osteoporosis-related fractures was determined on the entire skeletal system. According to WHO criteria, the patients were subdivided into four groups: 1, normal; 2, osteopenic; 3, osteoporotic without fractures; 4, severely osteoporotic. Weighting factors were determined by means of multivariate least-squares analysis and used to calculate a risk score of all parameters. The ability of the individual parameters and of the sum of discriminate between the individual groups was tested. If one considers the individual parameters (BMD and the fractal structural values for spongious and cortical bone), they allow a statistically significant separation of the four groups, although there is overlapping in the value ranges. In patients with fractures, there was a significant reduction in the cortical mineral density, accompanied by a deterioration in structural properties. The following individual values were obtained (minimum-mean-maximum): spongiosa BMD (mg ml-1), unfractured: 62-112-163, fractured: 9-48-77; cortical BMD (mg ml-1), unfractured: 190-287-405, fractured: 133-191-269; spongiosa structural parameter, unfractured: 0.35-0.73-1.01, fractured: 0.95-1.24-1.58; cortical structural parameter, unfractured: 18-31-65, fractured: 21-44-66. Above 77 mg ml-1 CaHA in the spongiosa and 270 mg ml-1 CaHA in cortical bone, no fractures were observed. By appropriately selecting the weighting factors, the score is free of overlapping between the groups with and without fractures (values: unfractured 1-9-15, fractured 16-21-29). With higher score values, the fracture risk is increasing.

Wrist arthroplasty with a new generation of prostheses in patients with rheumatoid arthritis.

The function of the wrist is frequently considerably impaired by early destruction in patients with rheumatoid arthritis. The aim of endoprosthetic arthroplasty is to restore functional use and provide freedom from pain. In our study a newly developed, uncemented wrist prosthesis was implanted in 30 patients (24 women and 6 men) with advanced destruction of the wrist. This wrist prosthesis is a hydroxyapatite-coated cobalt-chrome prosthesis with a titanium coating of the articular surfaces. The radial component has an articular surface inclination of 10 degrees toward the ulna, and the carpal component, which is anchored with its tip in the distal carpal bones and third metacarpal bone, has a double articular surface with a radial inclination of 10 degrees. At the 18-month follow-up visit, the following parameters were examined: x-ray, grip strength, range of motion, and the patient's subjective satisfaction. Good improvement of function was found in 92% of the patients; 87% were free of pain. Eighty-eight percent of the patients rated the outcome of surgery as good. If the indication is accurately diagnosed, this wrist prosthesis can markedly improve function, which in turn leads to high patient acceptance. Various salvage procedures remain open because of the minimal loss of bone stock and the uncemented implantation of the prosthesis.

Computerized analysis of gray-value profiles in spongy and cortical bone. Clinical experience.

RATIONALE AND OBJECTIVES: Osteoporosis is characterized by a loss of bone mineral density and deterioration of structure. The authors present a structural parameter for the quantitative assessment of osteoporotic changes in vertebral bone. METHODS: In 40 patients without or with known osteoporotic fractures, spongiosa and cortical bone mineral density was measured in lumbar vertebrae 1 to 3 by quantitative CT. Additional axial high-resolution CT slices were obtained for the structural analysis. In the spongiosa, the gray-value profile along a horizontal line in the CT slice was used, whereas in the cortical shell a profile was obtained from the cortical ridge. Both profiles were intersected with a horizontal line of variable position, and the maximum number of intersections was determined. RESULTS: The maximum number of intersections is significantly higher in cases with fractures (spongiosa 48.6, cortical shell 77.3) than in cases without fractures (spongiosa 42.1, cortical shell 62.4). It also correlates with bone mineral density and age. CONCLUSIONS: The presented method shows significantly different numeric results for patients with and without osteoporotic fractures. The analysis is easy to perform and provides additional information on the bone structure that may be used in combination with bone mineral density measurements.

Imaging of hamate bone fractures in conventional X-rays and high-resolution computed tomography. An in vitro study.

RATIONALE AND OBJECTIVES: To examine the ability to image fractures of the body and hook of the hamate bone in conventional X-rays and high-resolution computed tomography (HR-CT). MATERIALS AND METHODS: In an in vitro experiment using 18 cadaver hands, the hamate bone was fractured at different places. Before and after fracture, conventional X-rays were taken in different planes (anteroposterior, lateral, oblique, and carpal tunnel), and HR-CT was performed with 2-mm layer thickness in the axial, sagittal, and coronal plane. RESULTS: Taking into account all the conventional X-ray projections applied, the in vivo experiment revealed a sensitivity of 72.2%, a specificity of 88.8%, and an accuracy of 80.5%. For the HR-CT, the sensitivity was 100%, the specificity was 94.4%, and the accuracy was 97.2%. CONCLUSIONS: Fractures of the body and hook of the hamate cannot always be detected with certainty in the conventional X-ray image, even if different projectional planes are used. The HR-CT is the imaging procedure of choice for further clarification, and an axial or sagittal plane should be selected.

Bone mineral density and spongiosa architecture in correlation to vertebral body insufficiency fractures.

OBJECTIVE: The clinical value of spinal quantitative CT (sQCT) and the structural patterns of the vertebral bone were studied. MATERIAL AND METHODS: sQCT was performed on 246 patients with a mean age of 57 years for whom conventional lateral radiographies of the thoracic and lumbar spine were available. All patients were suffering from back pain of unknown etiology. The bone mineral density (BMD) of the midvertebral section of 3 lumbar vertebral bodies was determined by means of single-energy-(SE)-weighted QCT (85 kV). Spongiosa architecture and density profile analyses were made in the axial images. This was contrasted to BMD values ascertained in SE QCT. The mean BMD was compared to the number of fractures and the patients were divided into three groups: group I--no fracture; group II--one fracture; and group III > 1 fracture. RESULTS: The mean BMD was: 134.3 (74.1-187.5) mg hydroxyapatite (HA)/ml in group I; 79.6 (58.6-114.3) mg HA/ml in group II; and 52.4 (13.1-79.1) mg HA/ml in group III. A significant deterioration in spongiosa structure was found with increasing demineralization: strongly rarefied patterns predominated in the fracture groups II and III. CONCLUSION: sQCT provides a good risk assessment of the occurrence of vertebral body insufficiency fractures.

[The imaging of hamate fractures in the conventional X-ray and CT: experimental results and clinical experiences]. / Darstellung von Os hamatum-Frakturen im konventionellen Röntgenbild und CT: experimentelle Ergebnisse sowie klinische Erfahrungen.

PURPOSE: Examination of the ability to image fractures of the body and hook of the hamate bone in conventional X-rays and HR-CT. MATERIAL AND METHODS: In an in vitro experiment on 18 cadaver hands, the hamate bone was fractured at different localisations. Before and after fracture, conventional x-rays were taken in different projectional planes: a.-p., lateral, oblique and carpal tunnel view, as well as an HR-CT with 2 mm layer thickness in the axial, sagittal and coronal plane. In addition, 15 clinically verified hamate bone fractures (two body and 13 hook of hamate fractures) were reviewed retrospectively to assess the value of the imaging procedures that led to diagnosis. RESULTS: Taking into account all conventional x-ray projections applied, the in vitro experiment yielded a sensitivity of 72.2%, a specificity of 88.8% and an accuracy of 80.5%. For CT, the sensitivity was 100%, the specificity 94.4% and the accuracy 97.2%. In retrospective clinical evaluation, 60% of the existing fractures were identified in the conventional x-ray images. The remaining fractures were detected by additional procedures like scintigraphy, conventional tomography and CT. CONCLUSION: For the diagnosis of fractures of the body and hook of the hamate HR-CT is the imaging procedure of choice, in which case an axial or sagittal plane should be chosen.

[Development of a CT data-based score for prediction of fracture risk in osteoporosis]. / Entwicklung eines auf CT-Daten basierenden Scores zur Vorhersage des Frakturrisikos bei Osteoporose.

It should be examined how far BMD semiquantitative (profile analysis) and qualitative datas (architecture of spongy bone, age of patient) can be combined in one score in order to improve the assessment of fracture risk. SE-QCT was performed in 220 patients with a mean age of 55.8 (33-84) years from whom conventional X-ray images of the thoracic and lumbar spine were available. In the axial scans spongiosa architecture was classified and a density profile analysis was carried out. This was followed by gradation of BMD values, different types of spongiosa architecture, profile analysis and age of patient to a numerical score. This was compared to the number of fractures, whereby the patients were separated into three groups: group I = no fracture, group II = one fracture, group III = more than one fracture. The BMD values, types of spongiosa architecture, semiquantitative profile analysis can be significantly assigned to the groups I and II (p < 0.02), groups I and III (p < 0.001), and the groups II and III (p < 0.05). By combining BMD values, architecture of spongy bone, density profile analysis, and age of patients without fracture, scale 8-12 = patients with or without fracture, scale 13-16 = patients with at least one fracture [corrected].

MR diagnosis of retropatellar chondral lesions under compression. A comparison with histological findings.

PURPOSE: The aim of the study was to improve the chondromalacia patellae (CMP) diagnosis by MR imaging under defined compression of the retropatellar cartilage, using a specially designed knee compressor. The results were compared with histological findings to obtain an MR classification of CMP. METHOD: MR imaging was performed in in vitro studies of 25 knees from cadavers to investigate the effects of compression on the retropatellar articular cartilage. The results were verified by subsequent histological evaluation. RESULTS: There was a significant difference in cartilage thickness reduction and signal intensity behaviour under compression according to the stage of CMP. CONCLUSION: Based on the decrease in cartilage thickness, signal intensity behaviour under compression, and cartilage morphology, the studies permitted an MR classification of CMP into stages I-IV in line with the histological findings. Healthy cartilage was clearly distinguished, a finding which may optimize CMP diagnosis.

[Conventional arthrography in comparison with magnetic resonance tomography and arthroscopy in internal knee joint injuries: are there specific indications?]. / Die konventionelle Arthrographie im Vergleich zu Magnetresonanztomographie und Arthroskopie bei Kniegelenkbinnenläsionen: Verbleiben Indikationen?

Twenty-one patients with suspected internal knee joint lesions were examined prospectively. In all patients an MRI was carried out first and was followed within two weeks by an arthrography and an arthroscopy. Lesions of the menisci, cruciate ligaments, hyaline cartilage, and synovial tissues were evaluated. Arthroscopy findings were defined as the "gold standard". MRI achieved an accuracy of 96.4%, a sensitivity of 93.6%, and a specificity of 92.5%, whereas arthrography achieved an accuracy of 67.8%, a sensitivity of 66.6%, and a specificity of 71.4%. These statistical data as well as the single findings revealed no special indications for arthrography in suspected knee joint lesions.

[The quantitative determination of bone mineral content--a system comparison of similarly built computed tomographs]. / Quantitative Knochenmineralgehaltsbestimmung (QCT)--Systemvergleich baugleicher Computertomographen.

An intercomparison of 4 CT scanners of the same manufacturer was performed. The bone mineral content of 11 lumbar vertebral columns removed directly post mortem was determined in a specially constructed lucite-water phantom. Even devices of the same construction were shown to yield a variation in the quantitative evaluation markedly exceeding the annual physiological mineral loss. As long as scanner adjustment by physical calibration phantoms has not yet been established, a course assessment and therapy control of bone mineral content should always be carried out on the same QCT scanner.

[MRT-specific staging of chondromalacia patellae with the aid of a special knee compressor: a comparison with the arthroscopic findings]. / MRT-spezifische Einteilung der Chondromalacia patellae unter Zuhilfenahme eines speziellen Kniekompressors: Gegenüberstellung mit dem arthroskopischen Befund.

The present study proposes a new MRI-specific staging of chondromalacia patellae (CMP) which is based on cartilage thickness decrease and signal intensity behaviour under compression as well as cartilage morphology in the plain image. The investigation was performed in 30 patients with varying knee complaints who underwent arthroscopy after MR imaging. It was demonstrated that three CMP stages can already be differentiated by MRI under compression in arthroscopically healthy cartilage. This proves a marked improvement in the early diagnosis of CMP.