Hydrogel-based autologous chondrocyte implantation leads to subjective improvement levels comparable to scaffold based autologous chondrocyte implantation.

PURPOSE: Scaffold-based autologous chondrocyte implantation is a well-established treatment for cartilage defects in the knee joint. Hydrogel-based autologous chondrocyte implantation using an in situ polymerizable biomaterial is a relatively new treatment option for arthroscopic cartilage defects. It is therefore important to determine if there are significant differences in the outcomes. The aim of this study is to compare the outcomes (using subjective parameters) of hydrogel-based autologous chondrocyte implantation (NOVOCART® Inject) with the outcomes of scaffold based autologous chondrocyte Implantation (NOVOCART® 3D) using biphasic collagen scaffold. METHODS: The data of 50 patients, which were paired with 25 patients in each treatment group, was analyzed. The main parameters used for matching were gender, number of defects and localization. Both groups were compared based on Visual Analogue Scale (VAS) and subjective IKDC scores, both of which were examined pre-operatively and after 6, 12 and 24 months. RESULTS: Significant benefits in both VAS and IKDC scores after 2 years of follow-up in both groups were found. Comparing the groups, the results showed that in the hydrogel-based autologous chondrocyte implantation group, significant changes in IKDC scores are measurable after 6 months, while it takes 12 months until they are seen in the scaffold based autologous chondrocyte group. CONCLUSION: Hydrogel-based autologous chondrocyte and scaffold based autologous chondrocyte show comparable improvements and significant benefits to the patients' subjective well-being after a 2-year-follow-up. LEVEL OF EVIDENCE: III.

Third generation autologous chondrocyte implantation is a good treatment option for athletic persons.

PURPOSE: Autologous chondrocyte implantation is an established method for the treatment of joint cartilage damage. However, to date it has not been established that autologous chondrocyte implantation is an appropriate procedure for cartilage defects therapy in athletic persons. The aim of this study is to analyze if third-generation autologous chondrocyte implantation is an appropriate treatment for athletic persons with full cartilage defect of the knee joints. METHODS: A total of 84 patients were treated with third-generation autologous chondrocyte implantation (NOVOCART® 3D). The mean follow-up time was 8 years (5-14). Sports activity was measured via UCLA Activity Score and Tegner Activity Scale before the onset of knee pain and postoperatively in an annual clinical evaluation. 41 athletic persons and 43 non-athletic persons (UCLA-Cut-off: 7; Tegner Activity Scale-Cut-off: 4) were analyzed. Patient reported outcomes were captured using IKDC subjective, KOOS, Lysholm score and VAS score on movement. RESULTS: Patient reported outcomes (IKDC, VAS at rest, VAS on movement) showed significant improvement (p < 0.001) postoperatively. Athletic persons demonstrated significantly better results than non-athletic persons in the analyzed outcome scores (IKDC: p < 0.01, KOOS: p < 0.01, Lysholm score: p < 0.01). 96.4% of the patients were able to return to sport and over 50% returned or surpassed their preinjury sports level. The remaining patients were downgraded by a median of two points on the UCLA- and 2.5 on the Tegner Activity Scale. A shift from high-impact sports to active events and moderate or mild activities was found. Furthermore, it was shown that preoperative UCLA score and Tegner Activity Scale correlated significantly with the patient reported outcome postoperatively. CONCLUSION: Autologous chondrocyte implantation is a suitable treatment option for athletic persons with full-thickness cartilage defects in the knee. The return to sports activity is possible, but includes a shift from high-impact sports to less strenuous activities.

Development of a novel biodegradable porous iron-based implant for bone replacement.

Bone replacement and osteosynthesis require materials which can at least temporarily bear high mechanical loads. Ideally, these materials would eventually degrade and would be replaced by bone deposited from the host organism. To date several metals, notably iron and iron-based alloys have been identified as suitable materials because they combine high strength at medium corrosion rates. However, currently, these materials do not degrade within an appropriate amount of time. Therefore, the aim of the present study is the development of an iron-based degradable sponge-like (i.e. cellular) implant for bone replacement with biomechanically tailored properties. We used a metal powder sintering approach to manufacture a cylindrical cellular implant which in addition contains phosphor as an alloying element. No corrosion inhibiting effects of phosphorus have been found, the degradation rate was not altered. Implant prototypes were tested in an animal model. Bone reaction was investigated at the bone-implant-interface and inside the cellular spaces of the implant. Newly formed bone was growing into the cellular spaces of the implant after 12 months. Signs of implant degradation were detected but after 12 months, no complete degradation could be observed. In conclusion, iron-based open-porous cellular biomaterials seem promising candidates for the development of self-degrading and high load bearing bone replacement materials.

Third-generation autologous chondrocyte implantation after failed bone marrow stimulation leads to inferior clinical results.

PURPOSE: Third-generation autologous chondrocyte implantation (ACI) is an established and frequently used method and successful method for the treatment of full-thickness cartilage defects in the knee. There are also an increasing number of patients with autologous chondrocyte implantation as a second-line therapy that is used after failed bone marrow stimulation in the patient's history. The purpose of this study is to investigate the effect of previous bone marrow stimulation on subsequent autologous chondrocyte implantation therapy. In this study, the clinical results after the matrix-based autologous chondrocyte implantation in the knee in a follow-up over 3 years postoperatively were analysed. METHODS: Forty patients were included in this study. A total of 20 patients with cartilage defects of the knee were treated with third-generation autologous chondrocyte implantation (Novocart® 3D) as first-line therapy. The mean defect size was 5.4 cm2 (SD 2.6). IKDC subjective score and VAS were used for clinical evaluation after 6, 12, 24 and 36 months postoperatively. The results of these patients were compared with 20 matched patients with autologous chondrocyte implantation as second-line therapy. Matched pair analysis was performed by numbers of treated defects, defect location, defect size, gender, age and BMI. RESULTS: Both the first-line (Group I) and second-line group (Group II) showed significantly better clinical results in IKDC score and VAS score in the follow-up over 3 years compared with the preoperative findings. In addition, Group I showed significantly better results in the IKDC and VAS during the whole postoperative follow-up after 6, 12, 24 and 36 months compared to Group II with second-line autologous chondrocyte implantation (IKDC 6 months p = 0.015, 1 year p = 0.001, 2 years p = 0.001, 3 years p = 0.011). Additionally, we found a lower failure rate in Group I. No revision surgery was performed in Group I. The failure rate in the second-line Group II was 30%. CONCLUSION: This study showed that third-generation autologous chondrocyte implantation is a suitable method for the treatment of full-thickness cartilage defects. Both, Group I and Group II showed significant improvement in our follow-up. However, in comparing the results of the two groups, autologous chondrocyte implantation after failed bone marrow stimulation leads to worse clinical results. LEVEL OF EVIDENCE: III.

Revisability of polyetheretherketone suture anchors utilised in primary and revision Bankart repair.

BACKGROUND: Polyetheretherketone (PEEK) suture anchors are frequently used in Bankart shoulder stabilisation. This study analyzed the primary stability and revisability of PEEK anchors in-vitro in case of primary Bankart repair and revision Bankart repair after failed primary repair. METHODS: To simulate primary Bankart repair, 12 anchors (Arthrex PEEK PushLock® 3.5 mm) were implanted in 1, 3, 5, 7, 9 and 11 o'clock positions in cadaveric human glenoids and then cyclically tested. To simulate revision Bankart repair, 12 anchors were implanted in the same manner, over-drilled and 12 new anchors of the same diameter were implanted into the same bone socket as the primary anchors and then cyclically tested. The maximum failure loads (Fmax), system displacements, force at clinical failure and modes of failure were recorded. RESULTS: One primary anchor failed prematurely due to a technical problem. Three out of 12 revision anchors (25%) dislocated while setting the 25 N preload. The Fmax, the displacement and clinical failure of the remaining 9 revision anchors were non-significant when compared to the 11 primary repair anchors. The main mode of failure in the primary and revision Bankart surgery group was suture slippage. Anchor dislocations were observed four times in the primary and once in the revision repair groups. CONCLUSIONS: Revision Bankart repair using PEEK anchors of the same diameter in a pre-existing bone socket is possible but bears high risk of premature anchor failure and can jeopardize the reconstruction. PEEK suture anchor in revision Bankart surgery should be implanted in a new bone socket if possible.

Matrix based autologous chondrocyte implantation in children and adolescents: a match paired analysis in a follow-up over three years post-operation.

PURPOSE: The aim of this study is the investigation of the clinical results after third generation autologous chondrocyte implantation in the knee in a follow-up over three years post-operation. Our primary focus is on the effects of this procedure on children and adolescent patients as there is a lack of knowledge regarding the clinical outcomes in children/adolescents in particular when compared with adults. METHODS: A total of 40 patients (43 defects) <20 years with cartilage defects of the knee were treated with third generation ACI (Novocart® 3D). These defects were caused by osteochondritis dissecans (n = 13), acute trauma (<12 months) (n = 9), old trauma (>12 months) (n = 5) or unknown pathology (n = 13). The mean defect size was 5.2 cm2. IKDC subjective score and VAS (at rest and during activity) were used for clinical evaluation after 6, 12, 24 and 36 months post-operatively. The results of these patients were compared with 40 matched adult patients. Match paired analysis was performed by numbers of treated defects, defect location and defect size. All cartilage defects were arthroscopically classified with IKDC grade III-IV. All adult patients in the control group were treated with matrix based autologous chondrocyte implantation. RESULTS: All patients showed significantly better clinical results compared with the pre-operative findings in the follow-up over three years. We observed significantly better results in the IKDC score and VAS during the whole postoperative follow-up in children and adolescents after six, 12, 24 and 36 months compared with the adult control group. The IKDC score improved from 46.5 preoperative to 77.5 (+31) after three years in children and adolescents. Similarly, significantly lower stress pain after six months and one, two and three years was found in this group. CONCLUSION: This study showed that third generation autologous chondrocyte implantation is a suitable method for the treatment of full cartilage defects in children and adolescents.

Discrepancy between morphological findings in juvenile osteochondritis dissecans (OCD): a comparison of magnetic resonance imaging (MRI) and arthroscopy.

PURPOSE: The aim of this study was to assess the reliability of preoperative MRI for the staging of osteochondritis dissecans (OCD) lesions of the knee and the talus in juvenile patients, using arthroscopy as the gold standard of diagnosis. METHODS: Sixty-three juvenile patients (range 8-16 years) with an OCD of the knee or the talus underwent arthroscopy after MRI. In 54/9 out of 63 cases, 1.5/3 T MR scanners were used. The OCD stage was classified according the staging criteria of Dipaola et al. Arthroscopic findings were compared with MRI reports in each patient. RESULTS: From the 63 juvenile patients, MRI/arthroscopy revealed a stage I OCD in 4/19 patients, stage II in 31/22 patients, stage III in 22/9 patients and stage IV in 6/6 patients. No osteochondral pathology was evident in arthroscopy in seven out of 63 patients. The overall accuracy of preoperative MRI in staging an OCD lesion of the knee or the talus was 41.3%. In 33 out of 63 patients (52.4%), arthroscopy revealed a lower OCD stage than in the preoperative MRI grading, and in four out of 63 cases (6.4%), the intraoperative arthroscopic grading was worse than in preoperative MRI prior to surgery. The utilization of the 3 T MRI provided a correct diagnosis with 44.4%. CONCLUSIONS: Even with today's modern MRI scanners, it is not possible to predict an accurate OCD stage in children. The children's orthopaedist should not solely rely on the MRI when it comes to the decision to further conservative or surgical treatment of a juvenile OCD, but rather should take surgical therapy in consideration within persisting symptoms despite a low OCD stage provided by MRI. LEVEL OF EVIDENCE: III.

Straight proximal humeral nails are surrounded by more bone stock in comparison to bent nails in an experimental cadaveric study.

BACKGROUND: In the management of proximal humeral fractures intramedullary implants with bent and straight shape of the proximal part of nail are available. Based on data from previous studies on bone distribution in the humeral head, we hypothesized, that higher densities might exist in the bone stock surrounding straight nails in comparison to their angulated counterparts. With a known positive correlation between bone density and mechanical stability, this could indicate potentially higher rigidity of osteosyntheses done with straight implants. METHODS: We performed high resolution peripheral quantitative computed tomographies of the potential straight and bent implant bearing regions of 27 cadaveric proximal humeri. The acquired data were analyzed for differences between straight and bent Volumes of Interest as well as intra- and interindividual bone stock distribution. RESULTS: For both straight and bent volumes of interest a considerably declining bone mineral density was found in craniocaudal direction. Mean densities of bent volumes were significantly lower in comparison to their corresponding straight counterparts (p < 0.01) Intra-individual comparison yielded high bivariate correlations of the corresponding Volumes of Interest of the right and the left side (p < 0.01). CONCLUSIONS: Based on the volumetric data a statistically relevant biomechanical superiority of straight shaped implants can be assumed. Since we found a rapid decrease of bone density in cranio-caudal direction, intramedullary implants should be anchored as proximally in the subcortical area as possible to minimize the risk of displacement or cutout. The high correlation between the Volumes of Interest of the corresponding right and left sides could aid in preoperative planning when considering an intra- or extramedullary approach.

Toothpick injury simulating a pigmented villonodular synovialitis.

Injuries to the foot caused by foreign bodies are a frequent cause of local wounds and infections. In most cases, removal of the debris is easy and no comprehensive surgical care is needed. This case report is about a patient who stepped on a toothpick 10 years ago. The toothpick penetrated the intermetatarsal region I/II of the patient's right foot without any harm to bone or tendon. Assuming total removal of the toothpick only a partial removal was performed. Eight years after the injury a painless swelling occurred for the first time. The tumor was removed surgically. The histologic workup showed a pigmented villonodular synovitis. In the subsequent year swelling occurred again. Under the impression of recurrent pigmented villonodular synovitis a surgical revision was performed. Surprisingly, an almost completely preserved toothpick surrounded by a distinct reaction of a foreign body granuloma was found. In conclusion, foreign-body injuries, as easy as they might seem, need a careful diagnostic workup and sufficient therapy. With injuries documented in medical history, the possibility of a retained foreign body should be considered.

Cervical spine metastasis of multiple myeloma: a case report with 16 years of follow-up.

STUDY DESIGN: Presented is a case report of a 16-year clinical course of a patient with a multiple myeloma of the third cervical vertebra. OBJECTIVE: To describe a rare 16-year follow-up of a cervical multiple myeloma lesion that forced several surgical interventions. SUMMARY OF BACKGROUND DATA: Multiple myeloma is a systemic malignancy. It slowly causes bone destruction due to bone marrow infiltration. It is more common in the elderly and rarely affects the young. In patients with continuing neck pain and headache, one has to bear in mind the rare possibility of multiple myeloma or also other malignancies affecting the cervical spine. MATERIALS AND METHODS: Clinical case analysis, radiographs, magnetic resonance images, and histological sections of the lesion are discussed. Repeated surgical interventions were required due to progressive disease. RESULTS: Initial surgical treatment was aimed at palliation. However, this was in contrast to the slowly progressive clinical course. Thus, further surgical interventions were necessary. The patient died 16 years after the first procedure due to progression of the disease. CONCLUSION: Even in young patients presenting with neck pain and minor neurological symptoms, one should bear in mind the rare possibility of multiple myeloma. At the very least, a radiograph of the cervical spine and a routine blood test should be performed. Surgical interventions must take into account the relatively long period of survival in multiple myeloma patients compared to patients with other secondary bone tumors.

Malignant lymphoma of bone.

Malignant lymphoma of bone is rare. In many cases, its diagnosis is delayed because of unspecific clinical signs and equivocal radiographs. Therapy in general is multimodal, including surgery and radio- and chemotherapy. Our objective was to demonstrate the clinical and radiological aspects of the lesion to optimize diagnostic approaches and to evaluate treatment and prognostic factors. Thirty-six patients with malignant lymphoma of bone who were surgically treated over a 15-year-period were retrospectively reviewed. Seventeen of them showed a singular bone non-Hodgkin's lymphoma (NHL) which was classified as primary lymphoma of the bone (PLB). In 13 cases, dissemination of the disease with multiple bone or visceral involvement was apparent (dNHL). Six patients suffered from bone involvement due to Hodgkin's disease (HD). Surgical treatment was indicated for diagnostic reasons or complications due to the disease. Radiation and chemotherapy were part of the oncological treatment. The patients' mean age was 57 years. The main symptom in malignant bone lymphoma in 33 patients was pain, with an average duration of 8 months. In the secondary cases, bone involvement appeared on average 57 months after the initial diagnosis. An osteolytic pattern was seen in 58% of the lesions. Soft-tissue involvement was seen in 71% of cases (PLB 80%, dNHL 73%, HD 40%) and was the primary diagnostic sign associated with this disease. The 5-year survival rate was 61% (PLB 88%, dNHL 38%, HD 50%). Multiple vs solitary bone involvement was the most significant factor in the prognosis. Extraskeletal involvement significantly decreased survival. No correlation was found between gender, age, location, or histological subtypes and survival. Bone involvement in NHL appears late in the extraskeletal disease. The clinical appearance is nonspecific, and the delay between the onset of symptoms and diagnosis is often long. One of the major radiologic signs is the existence of a soft-tissue tumor surrounding the bone with little or no bone involvement on plain films. Treatment generally is conservative, based on the stage of the disease. Local radiation with or without systemic chemotherapy should be used. The long-term survival is favorable, but dependent on the stage of the disease and the amount of bone involvement.

Surgical treatment of bone metastases in patients with breast cancer.

In this retrospective study, the effect of surgical therapy on a series of 70 patients with breast cancer who were surgically treated for metastasis of the bone was evaluated. At presentation, 19 patients had one osseous lesion, 19 patients had multiple bone lesions, and 32 patients had additional visceral involvement. The surgical procedures included 60 palliative procedures, six radical resections, and four biopsies. In 14 surviving patients, the mean observation period was 35.6 +/- 40.1 months. Of the six patients with radically resected solitary bone lesions, five patients had systemic progression of the disease develop. Of the 19 patients with presumably solitary bone lesions, five currently are free of tumor. Of the 19 patients with multiple bone lesions and initially no visceral tumor spread, only two are alive. Of the 32 patients with additional visceral metastases at surgery, four are alive with the disease. For the entire group, the survival rate was 59% after 1 year, 36% after 2 years, 13% after 5 years, and 7% after 10 years. The only two independent factors that were associated with survival were the extent of the disease and the duration of symptoms from bone metastasis. These findings suggest that in orthopaedic surgery in patients with bone metastases secondary to breast cancer, wide resection is not likely to be necessary. Patients with solitary bone lesions have a 39% chance of living 5 years.

Multiple myeloma: surgery of the spine: retrospective analysis of 27 patients.

STUDY DESIGN: The authors report on the clinical course of 27 consecutive patients surgically treated for solitary or multiple myeloma of the spine. OBJECTIVES: To evaluate the complications, neurologic function, life quality, and survival after decompression of the spinal cord and stabilization of the spinal column in cases of conventionally untreatable pain, neurologic impairment, or spinal instability. SUMMARY OF BACKGROUND DATA: The clinical outcome in patients surgically treated for multiple myeloma of the spine has not been intensively studied. Because patients with myeloma often live longer than patients with bone metastases from other malignancies, it is important that these patients be examined and treated with methods specific to their needs and not only with those typically used for patients with metastatic disease. METHODS: The 27 patients had undergone the following surgical procedures: two dorsal decompressions, seven dorsal decompressions and stabilizations, 15 ventral decompressions and stabilizations, and three ventral and dorsal decompressions and stabilizations. Quality of life was measured by the Karnofsky Index, neurologic impairment according to Frankel, and survival by the Kaplan-Meier method. RESULTS: Life quality improved from 48% before surgery to 59% 1 month after surgery and 73% in 24 survivors after the first year. Comparison of their presurgical scores with the scores obtained 1 month after surgery revealed that 18 patients had improved, five patients stayed the same, and four patients declined. After 1 year the scores of all 24 surviving patients had improved from their presurgical levels. In the 21 patients with unimpaired preoperative neurologic function, one patient developed a paraparesis as a complication of surgery, while 20 remained unimpaired until death or 1 year after treatment. All six patients with neurologic deficits improved, two of them to normal function. Pain relief was evident in 26 cases. The mean length of postoperative survival was 49.7 months. Local tumor recurrence occurred in three of 27 patients (11.1%). CONCLUSION: The surgical treatment of myeloma of the spine seems to be an effective method of treatment with respect to neurologic function and life quality in selected cases.